WorldWideScience

Sample records for denuded subchondral bone

  1. Relationship between knee pain and the presence, location, size and phenotype of femorotibial denuded areas of subchondral bone as visualized by MRI.

    Science.gov (United States)

    Cotofana, S; Wyman, B T; Benichou, O; Dreher, D; Nevitt, M; Gardiner, J; Wirth, W; Hitzl, W; Kwoh, C K; Eckstein, F; Frobell, R B

    2013-09-01

    Conflicting associations between imaging biomarkers and pain in knee osteoarthritis (OA) have been reported. A relation between pain and denuded areas of subchondral bone (dABs) has been suggested and this study explores this relationship further by relating the presence, phenotype, location and size of dABs to different measures of knee pain. 633 right knees from the Osteoarthritis Initiative (OAI) (250 men, age 61.7 ± 9.6 yrs, BMI 29.4 ± 4.7 kg/m(2)) were included. Manual segmentation of the femorotibial cartilage plates was performed on 3 T coronal fast low angle shot with water excitation (FLASHwe) images. dABs were defined as areas where the subchondral bone was uncovered by cartilage. The following measures of pain were used: weightbearing-, non-weightbearing-, moderate-to-severe-, infrequent- and frequent knee pain. Using pain measures from subjects without dABs as a reference, those with at least one dAB had a 1.64-fold higher prevalence ratio [PR, 95% confidence interval (CI) 1.24-2.18] to have frequent and 1.45-fold higher for moderate-to-severe knee pain (95% CI 1.13-1.85). Subjects with dABs in central subregions had a 1.53-fold increased prevalence of having weightbearing pain (95% CI 1.20-1.97), especially when the central subregion was moderately (>10%) denuded (PR 1.81, 95% CI 1.35-2.42). Individuals with cartilage-loss-type dABs had a slightly higher prevalence (PR 1.13, 95% CI 1.00-1.27) of having frequent knee pain compared to individuals with intra-chondral-osteophyte-type dABs. This study supports a positive relation between femorotibial dABs and knee pain, especially when the dABs are located centrally (i.e., in weightbearing regions) or when the respective central subregion is moderately denuded. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  2. Presence, location, type and size of denuded areas of subchondral bone in the knee as a function of radiographic stage of OA - data from the OA initiative.

    Science.gov (United States)

    Frobell, R B; Wirth, W; Nevitt, M; Wyman, B T; Benichou, O; Dreher, D; Davies, R Y; Lee, J H; Baribaud, F; Gimona, A; Hudelmaier, M; Cotofana, S; Eckstein, F

    2010-05-01

    To assess the presence, location, type and size of denuded areas of subchondral bone (dAB) in the femorotibial joint, measured quantitatively with 3T MRI, in a large subset of OAI participants. One knee of 633 subjects (250 men, 383 women, aged 61.7+/-9.6 y) were studied, spanning all radiographic osteoarthritis (OA) stages. dABs were determined quantitatively using segmentations of coronal FLASHwe images, representing areas where the subchondral bone was not covered by cartilage. Post hoc visual examination of segmented images determined whether dABs represented full thickness cartilage loss or internal osteophyte. 7% Of the knees were Kellgren & Lawrence (KL) grade 0, 6% grade 1, 41% grade 2, 41% grade 3, and 5% grade 4. 39% Of the participants (48% of the men and 33% of the women) displayed dABs; 61% of the dABs represented internal osteophytes. 1/47 Participants with KL grade 0 displayed 'any' dAB whereas 29/32 of the KL grade 4 knees were affected. Even as early as KL grade 1, 29% of the participants showed dABs. There were significant relationships of dAB with increasing KL grades (Posteophytes were more frequent laterally (mainly posterior tibia and internal femur) whereas full thickness cartilage loss was more frequent medially (mainly external tibia and femur). dABs occur already at earliest stages of radiographic OA (KL grades 1 and 2) and become more common (and larger) with increasing disease severity. Almost all KL grade 4 knees exhibited dABs, with cartilage loss being more frequent than internal osteophytes. Copyright 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  3. [Subchondral bone in osteoarthritis: a review].

    Science.gov (United States)

    Pang, Jian; Cao, Yue-long; Shi, Yin-yu

    2011-08-01

    Osteoarthritis (OA) is the most prevalent of joint diseases,and its pathology is characterized by the degeneration of cartilage, sclerosis of subchondral bone, and osteophyte formation. Localization of the early lesions of OA has not been clarified, but many researchers have focused on cartilage and have considered that changes in subchondral bone occur subsequently to the degeneration of cartilage. However, a low bone mineral density, particularly in the knee joint with OA, high bone turnover, and efficacy of bone resorption inhibitors for OA have recently been reported, suggesting that subchondral bone plays an important role in the pathogenesis of OA. This review aims to make a conclusion about advancement in research of subchondral bone in osteoarthritis.

  4. [Mechanical behavior of the subchondral bone in the experimentally induced osteoarthritis].

    Science.gov (United States)

    Miyanaga, Y

    1979-06-01

    In order to evaluate the role of the subchondral bone (cancellous bone) in the development and progression of the joint degeneration, osteoarthritis of the knee joint was produced experimentally in the rabbits and viscoelasticity and strength of the subchondral bone from the femoral medial condyle have been investigated along with the pathological, histological study of the joint. The viscoelastic spectrometer and the Instron type testing machine were used. As the first change after operation, osteophyte formation around the joint margin has been observed before the initiation of the degeneration of articular cartilage and there is a possibility that mechanical properties of subchondral bone such as high deformability and low elasticity to the mechanism of osteophyte formation. Subchondral bone softening with marked increase of ultimate strain and phase lag, marked decrease of compressive elastic modulus and ultimate stress precedes or occurs concurrently with the degeneration of the articular cartilage. These facts indicate the relationship between the mechanical properties of the subchondral bone and joint degeneration. Once the joint degeneration starts, degeneration continues progressively while the subchondral bone tends to become brittle. These changes may be considered as a kind of functional adaptation to the damage or denudation of articular cartilage. It is postulated that some architectural changes of the subchondral bone may provide alterations of the mechanical properties. Biomechanical roles of the subchondral bone is suggested as one of the factors in the joint degeneration.

  5. Adaptation of subchondral bone in osteoarthritis

    DEFF Research Database (Denmark)

    Ding, Ming

    2004-01-01

    Osteoarthritis is a chronic joint disease with pathological changes in the articulating cartilage and all other tissues that occupy the joint. Radin and coworkers have suggested the involvement of subchondral bone in the disease process. However, evidence for an essential role in the etiology has...

  6. The basic science of the subchondral bone

    NARCIS (Netherlands)

    Madry, Henning; van Dijk, C. Niek; Mueller-Gerbl, Magdalena

    2010-01-01

    In the past decades, considerable efforts have been made to propose experimental and clinical treatments for articular cartilage defects. Yet, the problem of cartilage defects extending deep in the underlying subchondral bone has not received adequate attention. A profound understanding of the basic

  7. Bioactive Scaffolds for Regeneration of Cartilage and Subchondral Bone Interface

    Science.gov (United States)

    Deng, Cuijun; Zhu, Huiying; Li, Jiayi; Feng, Chun; Yao, Qingqiang; Wang, Liming; Chang, Jiang; Wu, Chengtie

    2018-01-01

    The cartilage lesion resulting from osteoarthritis (OA) always extends into subchondral bone. It is of great importance for simultaneous regeneration of two tissues of cartilage and subchondral bone. 3D-printed Sr5(PO4)2SiO4 (SPS) bioactive ceramic scaffolds may achieve the aim of regenerating both of cartilage and subchondral bone. We hypothesized that strontium (Sr) and silicon (Si) ions released from SPS scaffolds play a crucial role in osteochondral defect reconstruction. Methods: SPS bioactive ceramic scaffolds were fabricated by a 3D-printing method. The SEM and ICPAES were used to investigate the physicochemical properties of SPS scaffolds. The proliferation and maturation of rabbit chondrocytes stimulated by SPS bioactive ceramics were measured in vitro. The stimulatory effect of SPS scaffolds for cartilage and subchondral bone regeneration was investigated in vivo. Results: SPS scaffolds significantly stimulated chondrocyte proliferation, and SPS extracts distinctly enhanced the maturation of chondrocytes and preserved chondrocytes from OA. SPS scaffolds markedly promoted the regeneration of osteochondral defects. The complex interface microstructure between cartilage and subchondral bone was obviously reconstructed. The underlying mechanism may be related to Sr and Si ions stimulating cartilage regeneration by activating HIF pathway and promoting subchondral bone reconstruction through activating Wnt pathway, as well as preserving chondrocytes from OA via inducing autophagy and inhibiting hedgehog pathway. Conclusion: Our findings suggest that SPS scaffolds can help osteochondral defect reconstruction and well reconstruct the complex interface between cartilage and subchondral bone, which represents a promising strategy for osteochondral defect regeneration. PMID:29556366

  8. Alterations to the subchondral bone architecture during osteoarthritis : bone adaptation versus endochondral bone formation

    NARCIS (Netherlands)

    Cox, L.G.E.; Donkelaar, van C.C.; Rietbergen, van B.; Emans, P.J.; Ito, K.

    2013-01-01

    Objective Osteoarthritis (OA) is characterized by loss of cartilage and alterations in subchondral bone architecture. Changes in cartilage and bone tissue occur simultaneously and are spatially correlated, indicating that they are probably related. We investigated two hypotheses regarding this

  9. Microarchitectural adaptations in aging and osteoarthrotic subchondral bone tissues

    DEFF Research Database (Denmark)

    Ding, Ming

    2010-01-01

    . These diseases are among the major health care problems in terms of socio-economic costs. The overall goals of the current series of studies were to investigate the age-related and osteoarthrosis (OA) related changes in the 3-D microarchitectural properties, mechanical properties, collagen and mineral quality......-related development of guinea pig OA; secondly, the potential effects of hyaluronan on OA subchondral bone tissues; and thirdly, the effects on OA progression of an increase in subchondral bone density by inhibition of bone remodeling with a bisphosphonate. These investigations aimed to obtain more insight...... into the age-related and OA-related subchondral bone adaptations.   Microarchitectural adaptation in human aging cancellous bone The precision of micro-CT measurement is excellent. Accurate 3-D micro-CT image datasets can be generated by applying an appropriate segmentation threshold. A fixed threshold may...

  10. Vasoactive substances in subchondral bone of the dog knee

    DEFF Research Database (Denmark)

    Holm, I E; Ewald, Henrik Lykke; Bülow, J

    1990-01-01

    The purpose of the present study was to investigate regulatory mechanisms for subchondral bone blood flow. A model including elevation of joint cavity pressure in the immature dog knee was applied. The role of prostaglandins in bone blood flow regulation was indirectly examined by indomethacin...

  11. What drives osteoarthritis?-synovial versus subchondral bone pathology.

    Science.gov (United States)

    Hügle, Thomas; Geurts, Jeroen

    2017-09-01

    Subchondral bone and the synovium play an important role in the initiation and progression of OA. MRI often permits an early detection of synovial hypertrophy and bone marrow lesions, both of which can precede cartilage damage. Newer imaging modalities including CT osteoabsorptiometry and hybrid SPECT-CT have underlined the importance of bone in OA pathogenesis. The subchondral bone in OA undergoes an uncoupled remodelling process, which is notably characterized by macrophage infiltration and osteoclast formation. Concomitant increased osteoblast activity leads to spatial remineralization and osteosclerosis in end-stage disease. A plethora of metabolic and mechanical factors can lead to synovitis in OA. Synovial tissue is highly vascularized and thus exposed to systemic influences such as hypercholesterolaemia or low grade inflammation. This review aims to describe the current understanding of synovitis and subchondral bone pathology and their connection in OA. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Variable Bone Density of Scaphoid: Importance of Subchondral Screw Placement.

    Science.gov (United States)

    Swanstrom, Morgan M; Morse, Kyle W; Lipman, Joseph D; Hearns, Krystle A; Carlson, Michelle G

    2018-02-01

    Background  Ideal internal fixation of the scaphoid relies on adequate bone stock for screw purchase; so, knowledge of regional bone density of the scaphoid is crucial. Questions/Purpose  The purpose of this study was to evaluate regional variations in scaphoid bone density. Materials and Methods  Three-dimensional CT models of fractured scaphoids were created and sectioned into proximal/distal segments and then into quadrants (volar/dorsal/radial/ulnar). Concentric shells in the proximal and distal pole were constructed in 2-mm increments moving from exterior to interior. Bone density was measured in Hounsfield units (HU). Results  Bone density of the distal scaphoid (453.2 ± 70.8 HU) was less than the proximal scaphoid (619.8 ± 124.2 HU). There was no difference in bone density between the four quadrants in either pole. In both the poles, the first subchondral shell was the densest. In both the proximal and distal poles, bone density decreased significantly in all three deeper shells. Conclusion  The proximal scaphoid had a greater density than the distal scaphoid. Within the poles, there was no difference in bone density between the quadrants. The subchondral 2-mm shell had the greatest density. Bone density dropped off significantly between the first and second shell in both the proximal and distal scaphoids. Clinical Relevance  In scaphoid fracture ORIF, optimal screw placement engages the subchondral 2-mm shell, especially in the distal pole, which has an overall lower bone density, and the second shell has only two-third the density of the first shell.

  13. Subchondral bone in osteoarthritis: insight into risk factors and microstructural changes.

    Science.gov (United States)

    Li, Guangyi; Yin, Jimin; Gao, Junjie; Cheng, Tak S; Pavlos, Nathan J; Zhang, Changqing; Zheng, Ming H

    2013-01-01

    Osteoarthritis (OA) is a major cause of disability in the adult population. As a progressive degenerative joint disorder, OA is characterized by cartilage damage, changes in the subchondral bone, osteophyte formation, muscle weakness, and inflammation of the synovium tissue and tendon. Although OA has long been viewed as a primary disorder of articular cartilage, subchondral bone is attracting increasing attention. It is commonly reported to play a vital role in the pathogenesis of OA. Subchondral bone sclerosis, together with progressive cartilage degradation, is widely considered as a hallmark of OA. Despite the increase in bone volume fraction, subchondral bone is hypomineralized, due to abnormal bone remodeling. Some histopathological changes in the subchondral bone have also been detected, including microdamage, bone marrow edema-like lesions and bone cysts. This review summarizes basic features of the osteochondral junction, which comprises subchondral bone and articular cartilage. Importantly, we discuss risk factors influencing subchondral bone integrity. We also focus on the microarchitectural and histopathological changes of subchondral bone in OA, and provide an overview of their potential contribution to the progression of OA. A hypothetical model for the pathogenesis of OA is proposed.

  14. Subchondral Bone and the Osteochondral Unit: Basic Science and Clinical Implications in Sports Medicine.

    Science.gov (United States)

    Saltzman, Bryan M; Riboh, Jonathan C

    2018-06-01

    Articular cartilage injuries and early osteoarthritis are among the most common conditions seen by sports medicine physicians. Nonetheless, treatment options for articular degeneration are limited once the osteoarthritic cascade has started. Intense research is focused on the use of biologics, cartilage regeneration, and transplantation to help maintain and improve cartilage health. An underappreciated component of joint health is the subchondral bone. A comprehensive, nonsystematic review of the published literature was completed via a PubMed/MEDLINE search of the keywords "subchondral" AND "bone" from database inception through December 1, 2016. Clinical review. Level 4. Articles collected via the database search were assessed for the association of bone marrow lesions and osteoarthritis, cartilage regeneration, and ligamentous and meniscal injury; the clinical disorder known as painful bone marrow edema syndrome; and the subchondral bone as a target for medical and surgical intervention. A complex interplay exists between the articular cartilage of the knee and its underlying subchondral bone. The role of subchondral bone in the knee is intimately related to the outcomes from cartilage restoration procedures, ligamentous injury, meniscal pathology, and osteoarthritis. However, subchondral bone is often neglected when it should be viewed as a critical element of the osteochondral unit and a key player in joint health. Continued explorations into the intricacies of subchondral bone marrow abnormalities and implications for the advent of procedures such as subchondroplasty will inform further research efforts on how interventions aimed at the subchondral bone may provide durable options for knee joint preservation.

  15. Subchondral bone density distribution in the human femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Wright, David A.; Meguid, Michael; Lubovsky, Omri; Whyne, Cari M. [Sunnybrook Research Institute, Orthopaedic Biomechanics Laboratory, Toronto, Ontario (Canada)

    2012-06-15

    This study aims to quantitatively characterize the distribution of subchondral bone density across the human femoral head using a computed tomography derived measurement of bone density and a common reference coordinate system. Femoral head surfaces were created bilaterally for 30 patients (14 males, 16 females, mean age 67.2 years) through semi-automatic segmentation of reconstructed CT data and used to map bone density, by shrinking them into the subchondral bone and averaging the greyscale values (linearly related to bone density) within 5 mm of the articular surface. Density maps were then oriented with the center of the head at the origin, the femoral mechanical axis (FMA) aligned with the vertical, and the posterior condylar axis (PCA) aligned with the horizontal. Twelve regions were created by dividing the density maps into three concentric rings at increments of 30 from the horizontal, then splitting into four quadrants along the anterior-posterior and medial-lateral axes. Mean values for each region were compared using repeated measures ANOVA and a Bonferroni post hoc test, and side-to-side correlations were analyzed using a Pearson's correlation. The regions representing the medial side of the femoral head's superior portion were found to have significantly higher densities compared to other regions (p < 0.05). Significant side-to-side correlations were found for all regions (r {sup 2} = 0.81 to r {sup 2} = 0.16), with strong correlations for the highest density regions. Side-to-side differences in measured bone density were seen for two regions in the anterio-lateral portion of the femoral head (p < 0.05). The high correlation found between the left and right sides indicates that this tool may be useful for understanding 'normal' density patterns in hips affected by unilateral pathologies such as avascular necrosis, fracture, developmental dysplasia of the hip, Perthes disease, and slipped capital femoral head epiphysis. (orig.)

  16. Interleukin-6 from subchondral bone mesenchymal stem cells contributes to the pathological phenotypes of experimental osteoarthritis

    Science.gov (United States)

    Wu, Xiaofeng; Cao, Lei; Li, Fan; Ma, Chao; Liu, Guangwang; Wang, Qiugen

    2018-01-01

    As a main cause of morbidity in the aged population, osteoarthritis (OA) is characterized by cartilage destruction, synovium inflammation, osteophytes, and subchondral bone sclerosis. To date its etiology remains elusive. Recent data highlight an important role of subchondral bone in the onset and progression of OA. Therefore, elucidating the mechanisms underlying abnormal subchondral bone could be of importance in the treatment of OA. Interleukin-6 is a proinflammatory cytokine involved in many physiological and pathological processes. Although in vitro and in vivo studies have indicated that IL-6 is an important cytokine in the physiopathogenesis of OA, its effects on subchondral bone have not been studied in OA animal models. In this study, we aimed to i) investigate the role of IL-6 in the pathological phenotypes of OA subchondral bone MSCs including increase in cell numbers, mineralization disorder and abnormal type I collagen production; ii) explore whether the systemic blockade of IL-6 signaling could alleviate the pathological phenotypes of experimental OA. We found that IL-6 was over-secreted by OA subchondral bone MSCs compared with normal MSCs and IL-6/STAT3 signaling was over-activated in subchondral bone MSCs, which contributed to the pathological phenotypes of OA subchondral bone MSCs. More importantly, systemic inhibition of IL-6/STAT3 signaling with IL-6 antibody or STAT3 inhibitor AG490 decreased the severity of pathological phenotypes of OA subchondral bone MSCs and cartilage lesions in OA. Our findings provide strong evidence for a pivotal role for IL-6 signaling in OA and open up new therapeutic perspectives. PMID:29736207

  17. Bone mineral measurements of subchondral and trabecular bone in healthy and osteoporotic rabbits

    International Nuclear Information System (INIS)

    Castaneda, S; Largo, R.; Marcos, M.E.; Herrero-Beaumont, G.; Calvo, E.; Rodriguez-Salvanes, F.; Diaz-Curiel, M.

    2006-01-01

    Experimental models of osteoporosis in rabbits are useful to investigate anabolic agents because this animal has a fast bone turnover with predominant remodelling over the modelling processes. For that purpose, it is necessary to characterize the densitometric values of each type of bony tissue. To determine areal bone mass measurement in the spine and in trabecular, cortical and subchondral bone of the knee in healthy and osteoporotic rabbits. Bone mineral content and bone mineral density were measured in lumbar spine, global knee, and subchondral and cortical bone of the knee with dual energy X-ray absorptiometry using a Hologic QDR-1000/W densitometer in 29 skeletally mature female healthy New Zealand rabbits. Ten rabbits underwent triplicate scans for evaluation of the effect of repositioning. Osteoporosis was experimentally induced in 15 rabbits by bilateral ovariectomy and postoperative corticosteroid treatment for 4 weeks. Identical dual energy X-ray absorptiometry (DXA) studies were performed thereafter. Mean values of bone mineral content at the lumbar spine, global knee, subchondral bone and cortical tibial metaphysis were: 1934±217 mg, 878±83 mg, 149±14 mg and 29±7.0 mg, respectively. The mean values of bone mineral density at the same regions were: 298±24 mg/cm 2 , 455±32 mg/cm 2 , 617±60 mg/cm 2 and 678±163 mg/cm 2 , respectively. (orig.)

  18. Is there crosstalk between subchondral bone, cartilage, and meniscus in the pathogenesis of osteoarthritis?

    Science.gov (United States)

    Atik, O Şahap; Erdoğan, Deniz; Seymen, Cemile Merve; Bozkurt, Hasan Hüseyin; Kaplanoğlu, Gülnur Take

    2016-08-01

    This study aims to investigate if there is any crosstalk between subchondral bone, cartilage, and meniscus in the pathogenesis of osteoarthritis. Twelve female patients (mean age 64 years; range 59 to 71 years) with osteoarthritis in medial compartment were included in the study. The samples of subchondral bone, cartilage and meniscus were obtained during total knee arthroplasty. Degenerated tissue samples obtained from medial compartment were used as the experimental group (12 samples of subchondral bone and cartilage, 1x1 cm each; and 12 samples of meniscus, 1x1 cm each). Healthy tissue samples obtained from lateral compartment were used as the control group (12 samples of subchondral bone and cartilage; 1x1 cm each; and 12 samples of meniscus, 1x1 cm each). After decalcification, tissue samples were evaluated with light and transmission electron microscopy. In the experimental group, light microscopic evaluation of subchondral bone samples demonstrated that the cartilage-to-bone transition region had an irregular structure. Degenerated cartilage cells were observed in the transition region and bone cells were significantly corrupted. In the experimental group, light microscopic evaluation of the meniscus samples demonstrated that the intercellular tissue was partly corrupted. Separation and concentration of the collagen fibers were evident. All findings were supported with ultra structural evaluations. Our findings indicate that degeneration of subchondral bone, cartilage, and meniscus probably plays a role in the pathogenesis of osteoarthritis with crosstalk.

  19. In Vivo Quantitative Ultrasound Image Analysis of Femoral Subchondral Bone in Knee Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Jana Podlipská

    2013-01-01

    Full Text Available A potential of quantitative noninvasive knee ultrasonography (US for detecting changes in femoral subchondral bone related to knee osteoarthritis (OA was investigated. Thirty-nine patients referred to a knee arthroscopy underwent dynamic noninvasive US examination of the knee joint. The subchondral bone was semiautomatically segmented from representative US images of femoral medial and lateral condyles and intercondylar notch area. Subsequently, the normalized mean gray-level intensity profile, starting from the cartilage-bone interface and extending to the subchondral bone depth of ~1.7 mm, was calculated. The obtained profile was divided into 5 depth levels and the mean of each level, as well as the slope of the profile within the first two levels, was calculated. The US quantitative data were compared with the arthroscopic Noyes’ grading and radiographic Kellgren-Lawrence (K-L grading. Qualitatively, an increase in relative subchondral bone US gray-level values was observed as OA progressed. Statistically significant correlations were observed between normalized US mean intensity or intensity slope especially in subchondral bone depth level 2 and K-L grading (r=0.600, P<0.001; r=0.486, P=0.006, resp. or femoral arthroscopic scoring (r=0.332, P=0.039; r=0.335, P=0.037, resp.. This novel quantitative noninvasive US analysis technique is promising for detection of femoral subchondral bone changes in knee OA.

  20. Osteoarthritis alters the patellar bones subchondral trabecular architecture.

    Science.gov (United States)

    Hoechel, Sebastian; Deyhle, Hans; Toranelli, Mireille; Müller-Gerbl, Magdalena

    2017-09-01

    Following the principles of "morphology reveals biomechanics," the cartilage-osseous interface and the trabecular network show defined adaptation in response to physiological loading. In the case of a compromised relationship, the ability to support the load diminishes and the onset of osteoarthritis (OA) may arise. To describe and quantify the changes within the subchondral bone plate (SBP) and trabecular architecture, 10 human OA patellae were investigated by CT and micro-CT. The results are presented in comparison to a previously published dataset of 10 non-OA patellae which were evaluated in the same manner. The analyzed OA samples showed no distinctive mineralization pattern in regards to the physiological biomechanics, but a highly irregular disseminated distribution. In addition, no regularity in bone distribution and architecture across the trabecular network was found. We observed a decrease of material as the bone volume and trabecular thickness/number were significantly reduced. In comparison to non-OA samples, greatest differences for all parameters were found within the first mm of trabecular bone. The differences decreased toward the fifth mm in a logarithmic manner. The interpretation of the logarithmic relation leads to the conclusion that the main impact of OA on bony structures is located beneath the SBP and lessens with depth. In addition to the clear difference in material with approximately 12% less bone volume in the first mm in OA patellae, the architectural arrangement is more rod-like and isotropic, accounting for an architectural decrease in stability and support. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1982-1989, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  1. Early Changes of Articular Cartilage and Subchondral Bone in The DMM Mouse Model of Osteoarthritis

    OpenAIRE

    Fang, Hang; Huang, Lisi; Welch, Ian; Norley, Chris; Holdsworth, David W.; Beier, Frank; Cai, Daozhang

    2018-01-01

    To examine the early changes of articular cartilage and subchondral bone in the DMM mouse model of osteoarthritis, mice were subjected to DMM or SHAM surgery and sacrificed at 2-, 5- and 10-week post-surgery. Catwalk gait analyses, Micro-Computed Tomography, Toluidine Blue, Picrosirius Red and Tartrate-Resistant Acid Phosphatase (TRAP) staining were used to investigate gait patterns, joint morphology, subchondral bone, cartilage, collagen organization and osteoclasts activity, respectively. R...

  2. Subchondral bone in osteoarthritis: insight into risk factors and microstructural changes

    OpenAIRE

    Li, Guangyi; Yin, Jimin; Gao, Junjie; Cheng, Tak S; Pavlos, Nathan J; Zhang, Changqing; Zheng, Ming H

    2013-01-01

    Osteoarthritis (OA) is a major cause of disability in the adult population. As a progressive degenerative joint disorder, OA is characterized by cartilage damage, changes in the subchondral bone, osteophyte formation, muscle weakness, and inflammation of the synovium tissue and tendon. Although OA has long been viewed as a primary disorder of articular cartilage, subchondral bone is attracting increasing attention. It is commonly reported to play a vital role in the pathogenesis of OA. Subcho...

  3. Alterations of the subchondral bone in osteochondral repair – translational data and clinical evidence

    Directory of Open Access Journals (Sweden)

    P Orth

    2013-06-01

    Full Text Available Alterations of the subchondral bone are pathological features associated with spontaneous osteochondral repair following an acute injury and with articular cartilage repair procedures. The aim of this review is to discuss their incidence, extent and relevance, focusing on recent knowledge gained from both translational models and clinical studies of articular cartilage repair. Efforts to unravel the complexity of subchondral bone alterations have identified (1 the upward migration of the subchondral bone plate, (2 the formation of intralesional osteophytes, (3 the appearance of subchondral bone cysts, and (4 the impairment of the osseous microarchitecture as potential problems. Their incidence and extent varies among the different small and large animal models of cartilage repair, operative principles, and over time. When placed in the context of recent clinical investigations, these deteriorations of the subchondral bone likely are an additional, previously underestimated, factor that influences the long-term outcome of cartilage repair strategies. Understanding the role of the subchondral bone in both experimental and clinical articular cartilage repair thus holds great promise of being translated into further improved cell- or biomaterial-based techniques to preserve and restore the entire osteochondral unit.

  4. Contribution of Circulatory Disturbances in Subchondral Bone to the Pathophysiology of Osteoarthritis.

    Science.gov (United States)

    Aaron, Roy K; Racine, Jennifer; Dyke, Jonathan P

    2017-08-01

    This review describes the contributions of abnormal bone circulation to the pathophysiology of osteoarthritis. Combining dynamic imaging with MRI and PET with previous observations reveals that venous stasis and a venous outlet syndrome is most likely the key circulatory pathology associated with the initiation or progression of osteoarthritis. MRI and PET have revealed that venous outflow obstruction results in physicochemical changes in subchondral bone to which osteoblasts are responsive. The osteoblasts express an altered pattern of cytokines, many of which can serve as structural or signaling molecules contributing to both bone remodeling and cartilage degeneration. The patterns of circulatory changes are associated with alterations in the physicochemical environment of subchondral bone, including hypoxia. Osteoblast cytokines can transit the subchondral bone plate and calcified cartilage and communicate with chondrocytes.

  5. Effects of a phosphocitrate analogue on osteophyte, subchondral bone advance, and bone marrow lesions in Hartley guinea pigs.

    Science.gov (United States)

    Sun, Y; Kiraly, A J; Sun, A R; Cox, M; Mauerhan, D R; Hanley, E N

    2018-02-01

    The objectives of this study were: 1) to examine osteophyte formation, subchondral bone advance, and bone marrow lesions (BMLs) in osteoarthritis (OA)-prone Hartley guinea pigs; and 2) to assess the disease-modifying activity of an orally administered phosphocitrate 'analogue', Carolinas Molecule-01 (CM-01). Young Hartley guinea pigs were divided into two groups. The first group (n = 12) had drinking water and the second group (n = 9) had drinking water containing CM-01. Three guinea pigs in each group were euthanized at age six, 12, and 18 months, respectively. Three guinea pigs in the first group were euthanized aged three months as baseline control. Radiological, histological, and immunochemical examinations were performed to assess cartilage degeneration, osteophyte formation, subchondral bone advance, BMLs, and the levels of matrix metalloproteinse-13 (MMP13) protein expression in the knee joints of hind limbs. In addition to cartilage degeneration, osteophytes, subchondral bone advance, and BMLs increased with age. Subchondral bone advance was observed as early as six months, whereas BMLs and osteophytes were both observed mainly at 12 and 18 months. Fibrotic BMLs were found mostly underneath the degenerated cartilage on the medial side. In contrast, necrotic BMLs were found almost exclusively in the interspinous region. Orally administered CM-01 decreased all of these pathological changes and reduced the levels of MMP13 expression. Subchondral bone may play a role in cartilage degeneration. Subchondral bone changes are early events; formation of osteophytes and BMLs are later events in the OA disease process. Carolinas Molecule-01 is a promising small molecule candidate to be tested as an oral disease-modifying drug for human OA therapy. Cite this article : Y. Sun, A. J. Kiraly, A. R. Sun, M. Cox, D. R. Mauerhan, E. N. Hanley Jr. Effects of a phosphocitrate analogue on osteophyte, subchondral bone advance, and bone marrow lesions in Hartley guinea

  6. Pulsed CO2 laser for intra-articular cartilage vaporization and subchondral bone perforation in horses

    Science.gov (United States)

    Nixon, Alan J.; Roth, Jerry E.; Krook, Lennart P.

    1991-05-01

    A pulsed carbon dioxide laser was used to vaporize articular cartilage in four horses, and perforate the cartilage and subchondral bone in four horses. Both intercarpal joints were examined arthroscopically and either a 1 cm cartilage crater or a series of holes was created in the third carpal bone of one joint. The contralateral carpus served as a control. The horses were evaluated clinically for 8 weeks, euthanatized and the joints examined radiographically, grossly, and histologically. Pulsed carbon dioxide laser vaporized cartilage readily but penetrated bone poorly. Cartilage vaporization resulted in no greater swelling, heat, pain on flexion, lameness, or synovial fluid reaction than the sham procedure. Laser drilling resulted in a shallow, charred hole with a tenacious carbon residue, and in combination with the thermal damage to deeper bone, resulted in increased swelling, mild lameness and a low-grade, but persistent synovitis. Cartilage removal by laser vaporization resulted in rapid regrowth with fibrous and fibrovascular tissue and occasional regions of fibrocartilage at week 8. The subchondral bone, synovial membrane, and draining lymph nodes appeared essentially unaffected by the laser cartilage vaporization procedure. Conversely, carbon dioxide laser drilling of subchondral bone resulted in poor penetration, extensive areas of thermal necrosis of bone, and significant secondary damage to the apposing articular surface of the radial carpal bone. The carbon dioxide laser is a useful intraarticular instrument for removal of cartilage and has potential application in inaccessible regions of diarthrodial joints. It does not penetrate bone sufficiently to have application in subchondral drilling.

  7. Subchondral bone failure in overload arthrosis: a scanning electron microscopic study in horses.

    Science.gov (United States)

    Norrdin, R W; Stover, S M

    2006-01-01

    Mechanical overload leads to a common arthrosis in the metacarpal condyle of the fetlock joint of racehorses. This is usually asymptomatic but severe forms can cause lameness. Subchondral bone failure is often present and the predictability of the site provided an opportunity to study of the progression of bone failure from microcracks to actual collapse of subchondral bone. Twenty-five fetlock condyles from racehorses with various stages of disease were selected. Stages ranged from mild through severe subchondral bone sclerosis, to the collapse of bone and indentation or loss of cartilage known as 'traumatic osteochondrosis'. Parasagittal slices were radiographed and examined with scanning electron microscopy. Fine matrix cracks were seen in the subchondral bone layer above the calcified cartilage and suggested loss of water or other non-collagenous components. The earliest microcracks appeared to develop in the sclerotic bone within 1-3 mm of the calcified cartilage layer and extend parallel to it in irregular branching lines. Longer cracks or microfractures appeared to develop gaps as fragmentation occurred along the margins. Occasional osteoclastic resorption sites along the fracture lines indicated activated remodeling may have caused previous weakening. In one sample, smoothly ground fragments were found in a fracture gap. Bone collapse occurred when there was compaction of the fragmented matrix along the microfracture. Bone collapse and fracture lines through the calcified cartilage were associated with indentation of articular cartilage at the site.

  8. Changes of articular cartilage and subchondral bone after extracorporeal shockwave therapy in osteoarthritis of the knee.

    Science.gov (United States)

    Wang, Ching-Jen; Cheng, Jai-Hong; Chou, Wen-Yi; Hsu, Shan-Ling; Chen, Jen-Hung; Huang, Chien-Yiu

    2017-01-01

    We assessed the pathological changes of articular cartilage and subchondral bone on different locations of the knee after extracorporeal shockwave therapy (ESWT) in early osteoarthritis (OA). Rat knees under OA model by anterior cruciate ligament transaction (ACLT) and medial meniscectomy (MM) to induce OA changes. Among ESWT groups, ESWT were applied to medial (M) femur (F) and tibia (T) condyles was better than medial tibia condyle, medial femur condyle as well as medial and lateral (L) tibia condyles in gross osteoarthritic areas (posteophyte formation and subchondral sclerotic bone (psubchondral bone repair in all ESWT groups compared to OA group (p T(M+L) > F(M) in OA rat knees.

  9. Prevalence of subchondral bone pathological changes in the distal metacarpi/metatarsi of racing Thoroughbred horses.

    Science.gov (United States)

    Bani Hassan, E; Mirams, M; Mackie, E J; Whitton, R C

    2017-10-01

    To investigate the prevalence of microscopic subchondral bone injury in the distal metacarpi/tarsi of Thoroughbred racehorses and associations with recent and cumulative training history. Metacarpi/metatarsi were obtained from postmortem examination of Thoroughbred racehorses. The severity of palmar/plantar osteochondral disease (POD) was graded in forelimbs from 38 horses and in hindlimbs from a separate cohort of 45 horses. Forelimb samples were embedded in methyl methacrylate and examined using backscattered scanning electron microscopy. Microfracture density in the condylar subchondral bone was determined. Horizontal subchondral bone fractures were identified in hindlimb samples using sections of demineralised tissue. Empty osteocyte lacunae were quantified in hindlimb samples using sections of demineralised tissue. The prevalence of gross POD was 65.8% (95% confidence interval (CI) 48.7-80.4%) in the forelimb and 57.8% (95% CI 42.2-72.3%) in the hindlimb cohort of horses. Microfractures occurred in the forelimbs of 97.4% (95% CI 86.2-99.9%) of horses. Microfracture density in forelimbs increased with age (r s  = 0.50, P = 0.001), the number of race starts (r s  = 0.47, P = 0.003) and was greater in the medial condyles of horses in training than in those not in training (n = 21, median: 3.1/mm; range: 0.8-10.0 vs n = 17, 1.4/mm; 0-4.5, P = 0.008). Empty osteocyte lacunae were observed in the subchondral bone of hindlimbs in 97.7% (95% CI 88.0-99.9%) of 44 horses. Subchondral bone pathology occurs with a high prevalence in Thoroughbred racehorses presented for postmortem examination. The accumulation of subchondral bone damage with longer career duration is consistent with bone fatigue. © 2017 Australian Veterinary Association.

  10. EFFECTS OF HYALURONAN ON THREE-DIMENSIONAL MICROARCHITECTURE OF SUBCHONDRAL BONE TISSUES IN GUINEA PIG PRIMARY OSTEOARTHROSIS

    DEFF Research Database (Denmark)

    Ding, Ming

    Introduction: It is not known whether hyaluronan (HA) has any effect on the underlying subchondral bone tissues. This study was to investigate the effects of high molecular weight HA (1.5x106 Daltons) intra-articular injection on subchondral bone tissues. Methods: Fifty-six male guinea pigs (6...

  11. A novel algorithm for a precise analysis of subchondral bone alterations

    Science.gov (United States)

    Gao, Liang; Orth, Patrick; Goebel, Lars K. H.; Cucchiarini, Magali; Madry, Henning

    2016-01-01

    Subchondral bone alterations are emerging as considerable clinical problems associated with articular cartilage repair. Their analysis exposes a pattern of variable changes, including intra-lesional osteophytes, residual microfracture holes, peri-hole bone resorption, and subchondral bone cysts. A precise distinction between them is becoming increasingly important. Here, we present a tailored algorithm based on continuous data to analyse subchondral bone changes using micro-CT images, allowing for a clear definition of each entity. We evaluated this algorithm using data sets originating from two large animal models of osteochondral repair. Intra-lesional osteophytes were detected in 3 of 10 defects in the minipig and in 4 of 5 defects in the sheep model. Peri-hole bone resorption was found in 22 of 30 microfracture holes in the minipig and in 17 of 30 microfracture holes in the sheep model. Subchondral bone cysts appeared in 1 microfracture hole in the minipig and in 5 microfracture holes in the sheep model (n = 30 holes each). Calculation of inter-rater agreement (90% agreement) and Cohen’s kappa (kappa = 0.874) revealed that the novel algorithm is highly reliable, reproducible, and valid. Comparison analysis with the best existing semi-quantitative evaluation method was also performed, supporting the enhanced precision of this algorithm. PMID:27596562

  12. Ultrasound arthroscopy of human knee cartilage and subchondral bone in vivo.

    Science.gov (United States)

    Liukkonen, Jukka; Lehenkari, Petri; Hirvasniemi, Jukka; Joukainen, Antti; Virén, Tuomas; Saarakkala, Simo; Nieminen, Miika T; Jurvelin, Jukka S; Töyräs, Juha

    2014-09-01

    Arthroscopic ultrasound imaging enables quantitative evaluation of articular cartilage. However, the potential of this technique for evaluation of subchondral bone has not been investigated in vivo. In this study, we address this issue in clinical arthroscopy of the human knee (n = 11) by determining quantitative ultrasound (9 MHz) reflection and backscattering parameters for cartilage and subchondral bone. Furthermore, in each knee, seven anatomical sites were graded using the International Cartilage Repair Society (ICRS) system based on (i) conventional arthroscopy and (ii) ultrasound images acquired in arthroscopy with a miniature transducer. Ultrasound enabled visualization of articular cartilage and subchondral bone. ICRS grades based on ultrasound images were higher (p ultrasound-based ICRS grades were expected as ultrasound reveals additional information on, for example, the relative depth of the lesion. In line with previous literature, ultrasound reflection and scattering in cartilage varied significantly (p ultrasound parameters and structure or density of subchondral bone could be demonstrated. To conclude, arthroscopic ultrasound imaging had a significant effect on clinical grading of cartilage, and it was found to provide quantitative information on cartilage. The lack of correlation between the ultrasound parameters and bone properties may be related to lesser bone change or excessive attenuation in overlying cartilage and insufficient power of the applied miniature transducer. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  13. Infrared spectroscopy reveals both qualitative and quantitative differences in equine subchondral bone during maturation

    Science.gov (United States)

    Kobrina, Yevgeniya; Isaksson, Hanna; Sinisaari, Miikka; Rieppo, Lassi; Brama, Pieter A.; van Weeren, René; Helminen, Heikki J.; Jurvelin, Jukka S.; Saarakkala, Simo

    2010-11-01

    The collagen phase in bone is known to undergo major changes during growth and maturation. The objective of this study is to clarify whether Fourier transform infrared (FTIR) microspectroscopy, coupled with cluster analysis, can detect quantitative and qualitative changes in the collagen matrix of subchondral bone in horses during maturation and growth. Equine subchondral bone samples (n = 29) from the proximal joint surface of the first phalanx are prepared from two sites subjected to different loading conditions. Three age groups are studied: newborn (0 days old), immature (5 to 11 months old), and adult (6 to 10 years old) horses. Spatial collagen content and collagen cross-link ratio are quantified from the spectra. Additionally, normalized second derivative spectra of samples are clustered using the k-means clustering algorithm. In quantitative analysis, collagen content in the subchondral bone increases rapidly between the newborn and immature horses. The collagen cross-link ratio increases significantly with age. In qualitative analysis, clustering is able to separate newborn and adult samples into two different groups. The immature samples display some nonhomogeneity. In conclusion, this is the first study showing that FTIR spectral imaging combined with clustering techniques can detect quantitative and qualitative changes in the collagen matrix of subchondral bone during growth and maturation.

  14. Multi-scale physico-chemical phenomena in articular cartilage and subchondral bone

    NARCIS (Netherlands)

    Pouran, Behdad

    2017-01-01

    Articular cartilage and its connecting subchondral bone plate are main compartments that play an important role in proper mechanical functioning of diarthrodial joints. However, in ageing and osteoarthritis structural changes propagate in these tissues, which impairs them for proper functioning. One

  15. Hardness of the subchondral bone of the patella in the normal state, in chondromalacia, and in osteoarthrosis.

    Science.gov (United States)

    Björkström, S; Goldie, I F

    1982-06-01

    The hardness of bone is its property of withstanding the impact of a penetrating agent. It has been found that articular degenerative changes in, for example, the tibia (knee) are combined with a decrease in the hardness of the subchondral bone. In this investigation the hardness of subchondral bone in chondromalacia and osteoarthrosis of the patella has been analysed and compared with normal subchondral bone. Using an indentation method originally described by Brinell the hardness of the subchondral bone was evaluated in 7 normal patellae, in 20 with chondromalacia and in 33 with osteoarthrosis. A microscopic and microradiographic study of the subchondral bone was carried out simultaneously. Hardness was lowest in the normal material. The mean hardness value beneath the degenerated cartilage differed only slightly from that of the normal material, but the variation of values was increased. The hardness in bone in the chondromalacia area was lower than the hardness in bone covered by surrounding normal cartilage. The mean hardness value in bone beneath normal parts of cartilage in specimens with chondromalacia was higher than the mean hardness value of the normal material. In the microscopic and microradiographic examination it became evident that there was a relationship between trabecular structure and subchondral bone hardness; high values: coarse and solid structure; low values: slender and less regular structure.

  16. Subchondral Bone Plate Thickening Precedes Chondrocyte Apoptosis and Cartilage Degradation in Spontaneous Animal Models of Osteoarthritis

    OpenAIRE

    Zamli, Zaitunnatakhin; Robson Brown, Kate; Tarlton, John F.; Adams, Mike A.; Torlot, Georgina E.; Cartwright, Charlie; Cook, William A.; Vassilevskaja, Kristiina; Sharif, Mohammed

    2014-01-01

    Osteoarthritis (OA) is the most common joint disorder characterised by bone remodelling and cartilage degradation and associated with chondrocyte apoptosis. These processes were investigated at 10, 16, 24, and 30 weeks in Dunkin Hartley (DH) and Bristol Strain 2 (BS2) guinea pigs that develop OA spontaneously. Both strains had a more pronounced chondrocyte apoptosis, cartilage degradation, and subchondral bone changes in the medial than the lateral side of the tibia, and between strains, the ...

  17. Effects of a phosphocitrate analogue on osteophyte, subchondral bone advance, and bone marrow lesions in Hartley guinea pigs

    Science.gov (United States)

    Kiraly, A. J.; Sun, A. R.; Cox, M.; Mauerhan, D. R.; Hanley, E. N.

    2018-01-01

    Objectives The objectives of this study were: 1) to examine osteophyte formation, subchondral bone advance, and bone marrow lesions (BMLs) in osteoarthritis (OA)-prone Hartley guinea pigs; and 2) to assess the disease-modifying activity of an orally administered phosphocitrate ‘analogue’, Carolinas Molecule-01 (CM-01). Methods Young Hartley guinea pigs were divided into two groups. The first group (n = 12) had drinking water and the second group (n = 9) had drinking water containing CM-01. Three guinea pigs in each group were euthanized at age six, 12, and 18 months, respectively. Three guinea pigs in the first group were euthanized aged three months as baseline control. Radiological, histological, and immunochemical examinations were performed to assess cartilage degeneration, osteophyte formation, subchondral bone advance, BMLs, and the levels of matrix metalloproteinse-13 (MMP13) protein expression in the knee joints of hind limbs. Results In addition to cartilage degeneration, osteophytes, subchondral bone advance, and BMLs increased with age. Subchondral bone advance was observed as early as six months, whereas BMLs and osteophytes were both observed mainly at 12 and 18 months. Fibrotic BMLs were found mostly underneath the degenerated cartilage on the medial side. In contrast, necrotic BMLs were found almost exclusively in the interspinous region. Orally administered CM-01 decreased all of these pathological changes and reduced the levels of MMP13 expression. Conclusion Subchondral bone may play a role in cartilage degeneration. Subchondral bone changes are early events; formation of osteophytes and BMLs are later events in the OA disease process. Carolinas Molecule-01 is a promising small molecule candidate to be tested as an oral disease-modifying drug for human OA therapy. Cite this article: Y. Sun, A. J. Kiraly, A. R. Sun, M. Cox, D. R. Mauerhan, E. N. Hanley Jr. Effects of a phosphocitrate analogue on osteophyte, subchondral bone advance, and

  18. Subchondral Bone Plate Thickening Precedes Chondrocyte Apoptosis and Cartilage Degradation in Spontaneous Animal Models of Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Zaitunnatakhin Zamli

    2014-01-01

    Full Text Available Osteoarthritis (OA is the most common joint disorder characterised by bone remodelling and cartilage degradation and associated with chondrocyte apoptosis. These processes were investigated at 10, 16, 24, and 30 weeks in Dunkin Hartley (DH and Bristol Strain 2 (BS2 guinea pigs that develop OA spontaneously. Both strains had a more pronounced chondrocyte apoptosis, cartilage degradation, and subchondral bone changes in the medial than the lateral side of the tibia, and between strains, the changes were always greater and faster in DH than BS2. In the medial side, a significant increase of chondrocyte apoptosis and cartilage degradation was observed in DH between 24 and 30 weeks of age preceded by a progressive thickening and stiffening of subchondral bone plate (Sbp. The Sbp thickness consistently increased over the 30-week study period but the bone mineral density (BMD of the Sbp gradually decreased after 16 weeks. The absence of these changes in the medial side of BS2 may indicate that the Sbp of DH was undergoing remodelling. Chondrocyte apoptosis was largely confined to the deep zone of articular cartilage and correlated with thickness of the subchondral bone plate suggesting that cartilage degradation and chondrocyte apoptosis may be a consequence of continuous bone remodelling during the development of OA in these animal models of OA.

  19. Characterization of articular cartilage and subchondral bone changes in the rat anterior cruciate ligament transection and meniscectomized models of osteoarthritis.

    Science.gov (United States)

    Hayami, Tadashi; Pickarski, Maureen; Zhuo, Ya; Wesolowski, Gregg A; Rodan, Gideon A; Duong, Le T

    2006-02-01

    Osteoarthritis (OA) is a chronic joint disease characterized by cartilage destruction, subchondral bone sclerosis, and osteophyte formation. Subchondral bone stiffness has been proposed to initiate and/or contribute to cartilage deterioration in OA. The purpose of this study was to characterize subchondral bone remodeling, cartilage damage, and osteophytosis during the disease progression in two models of surgically induced OA. Rat knee joints were subjected either to anterior cruciate ligament transection (ACLT) alone or in combination with resection of medial menisci (ACLT + MMx). Histopathological changes in the surgical joints were compared with sham at 1, 2, 4, 6, and 10 weeks post-surgery. Using a modified Mankin scoring system, we demonstrate that articular cartilage damage occurs within 2 weeks post-surgery in both surgical models. Detectable cartilage surface damage and proteoglycan loss were observed as early as 1 week post-surgery. These were followed by the increases in vascular invasion into cartilage, in loss of chondrocyte number and in cell clustering. Histomorphometric analysis revealed subchondral bone loss in both models within 2 weeks post-surgery followed by significant increases in subchondral bone volume relative to sham up to 10 weeks post-surgery. Incidence of osteophyte formation was optimally observed in ACLT joints at 10 weeks and in ACLT + MMx joints at 6 weeks post-surgery. In summary, the two surgically induced rat OA models share many characteristics seen in human and other animal models of OA, including progressive articular cartilage degradation, subchondral bone sclerosis, and osteophyte formation. Moreover, increased subchondral bone resorption is associated with early development of cartilage lesions, which precedes significant cartilage thinning and subchondral bone sclerosis. Together, these findings support a role for bone remodeling in OA pathogenesis and suggest that these rat models are suitable for evaluating bone

  20. Does subchondral bone of the equine proximal phalanx adapt to race training?

    Science.gov (United States)

    Noble, Phillipa; Singer, Ellen R; Jeffery, Nathan S

    2016-07-01

    Sagittal fractures of the first phalanx are a common, potentially catastrophic injury in racehorses. These fractures are often linked to an acute, one time, biomechanical event; however, recent evidence implies that chronic exposure to stress can lead to the accumulation of bony changes that affect the structural integrity of the bone and increase the likelihood of fracture. The aim of the study was to compare variations of two common metrics of bone adaptation - subchondral bone density and thickness across the proximal articular surface of the first phalanx in Thoroughbred horses that (1) raced but never experienced a first phalanx fracture (Raced Control); (2) raced and had experienced fracture of the contralateral first phalanx (Contralateral to Fracture); (3) had never raced or experienced a first phalanx fracture (Unraced Control). A total of 22 first phalangeal bones were sampled post-mortem and imaged using micro-computed tomography calibrated for mineral density measures. Measurements of volumetric subchondral bone mineral density and thickness were taken from images at five sites from medial to lateral, in three coronal planes (25, 50 and 75% dorsal-palmar). At each of the 15 sites, measurements were repeated and averaged across 10 adjacent micro-computed tomography slices of bone, spanning 0.75 mm. The magnitude and variance of these measurements were compared between sites and between cohorts with non-parametric statistical tests. Across the proximal osteochondral surface of the first phalanx, the pattern of subchondral bone volumetric bone mineral density and thickness varied with each coronal section studied. The subchondral bone thickness was greater for the central and dorsal coronal sections, compared with the palmar section. For the race-fit groups (Raced Control and Contralateral to Fracture), the highest volumetric bone mineral density was in the central sagittal groove. The volumetric bone mineral density was significantly greater in the

  1. Technical Report: Correlation Between the Repair of Cartilage and Subchondral Bone in an Osteochondral Defect Using Bilayered, Biodegradable Hydrogel Composites

    NARCIS (Netherlands)

    Lu, S.; Lam, J.; Trachtenberg, J.E.; Lee, E.J.; Seyednejad, H.; Beucken, J.J.J.P van den; Tabata, Y.; Kasper, F.K.; Scott, D.W.; Wong, M.E.; Jansen, J.A.; Mikos, A.G.

    2015-01-01

    The present work investigated correlations between cartilage and subchondral bone repair, facilitated by a growth factor-delivering scaffold, in a rabbit osteochondral defect model. Histological scoring indices and microcomputed tomography morphological parameters were used to evaluate cartilage and

  2. Co-expression of DKK-1 and Sclerostin in Subchondral Bone of the Proximal Femoral Heads from Osteoarthritic Hips

    OpenAIRE

    Zarei, Allahdad; Hulley, Philippa A.; Sabokbar, Afsie; Javaid, M. Kassim

    2017-01-01

    Background Osteoarthritis (OA) is a progressively degenerative joint disease influenced by structural and metabolic factors. There is growing evidence that subchondral bone is involved in both symptomatic and structural progression in OA. The Wnt pathway has been implicated in the progression of OA but the expression and function of the Wnt inhibitors, Dikkopf (DKK-1) and sclerostin (SOST), are unclear. Methods We examined the regional distribution of DKK-1 and SOST in subchondral bone of the...

  3. Subchondral bone density distribution of the talus in clinically normal Labrador Retrievers.

    Science.gov (United States)

    Dingemanse, W; Müller-Gerbl, M; Jonkers, I; Vander Sloten, J; van Bree, H; Gielen, I

    2016-03-15

    Bones continually adapt their morphology to their load bearing function. At the level of the subchondral bone, the density distribution is highly correlated with the loading distribution of the joint. Therefore, subchondral bone density distribution can be used to study joint biomechanics non-invasively. In addition physiological and pathological joint loading is an important aspect of orthopaedic disease, and research focusing on joint biomechanics will benefit veterinary orthopaedics. This study was conducted to evaluate density distribution in the subchondral bone of the canine talus, as a parameter reflecting the long-term joint loading in the tarsocrural joint. Two main density maxima were found, one proximally on the medial trochlear ridge and one distally on the lateral trochlear ridge. All joints showed very similar density distribution patterns and no significant differences were found in the localisation of the density maxima between left and right limbs and between dogs. Based on the density distribution the lateral trochlear ridge is most likely subjected to highest loads within the tarsocrural joint. The joint loading distribution is very similar between dogs of the same breed. In addition, the joint loading distribution supports previous suggestions of the important role of biomechanics in the development of OC lesions in the tarsus. Important benefits of computed tomographic osteoabsorptiometry (CTOAM), i.e. the possibility of in vivo imaging and temporal evaluation, make this technique a valuable addition to the field of veterinary orthopaedic research.

  4. Morphological studies at subchondral bone structures in human early arthrosis. Final report

    International Nuclear Information System (INIS)

    1992-01-01

    Quantitative histomorphometric studies using an image analysis system were performed simultaneously on hyaline cartilage, calcified cartilage and subchondral cancellous bone of human tibial heads for detailed information about the pathogenesis of arthrosis. Joint structures need to be fully detected in three dimensions since measurement values are more affected by topographical aspects than by either age, or sex, or arthrosin stage. Mechanical factors were found to affect essentially the initiation and progression of arthrosis. Results are demonstrated in detail. (orig.) [de

  5. Early Changes of Articular Cartilage and Subchondral Bone in The DMM Mouse Model of Osteoarthritis.

    Science.gov (United States)

    Fang, Hang; Huang, Lisi; Welch, Ian; Norley, Chris; Holdsworth, David W; Beier, Frank; Cai, Daozhang

    2018-02-12

    To examine the early changes of articular cartilage and subchondral bone in the DMM mouse model of osteoarthritis, mice were subjected to DMM or SHAM surgery and sacrificed at 2-, 5- and 10-week post-surgery. Catwalk gait analyses, Micro-Computed Tomography, Toluidine Blue, Picrosirius Red and Tartrate-Resistant Acid Phosphatase (TRAP) staining were used to investigate gait patterns, joint morphology, subchondral bone, cartilage, collagen organization and osteoclasts activity, respectively. Results showed OA progressed over 10-week time-course. Gait disparity occurred only at 10-week post-surgery. Osteophyte formed at 2-week post-surgery. BMDs of DMM showed no statistical differences comparing to SHAM at 2 weeks, but BV/TV is much higher in DMM mice. Increased BMD was clearly found at 5- and 10-week post-surgery in DMM mice. TRAP staining showed increased osteoclast activity at the site of osteophyte formation of DMM joints at 5- and 10-week time points. These results showed that subchondral bone turnover might occurred earlier than 2 weeks in this mouse DMM model. Gait disparity only occurred at later stage of OA in DMM mice. Notably, patella dislocation could occur in some of the DMM mice and cause a different pattern of OA in affected knee.

  6. In vivo cyclic compression causes cartilage degeneration and subchondral bone changes in mouse tibiae.

    Science.gov (United States)

    Ko, Frank C; Dragomir, Cecilia; Plumb, Darren A; Goldring, Steven R; Wright, Timothy M; Goldring, Mary B; van der Meulen, Marjolein C H

    2013-06-01

    Alterations in the mechanical loading environment in joints may have both beneficial and detrimental effects on articular cartilage and subchondral bone, and may subsequently influence the development of osteoarthritis (OA). Using an in vivo tibial loading model, the aim of this study was to investigate the adaptive responses of cartilage and bone to mechanical loading and to assess the influence of load level and duration. Cyclic compression at peak loads of 4.5N and 9.0N was applied to the left tibial knee joint of adult (26-week-old) C57BL/6 male mice for 1, 2, and 6 weeks. Only 9.0N loading was utilized in young (10-week-old) mice. Changes in articular cartilage and subchondral bone were analyzed by histology and micro-computed tomography. Mechanical loading promoted cartilage damage in both age groups of mice, and the severity of joint damage increased with longer duration of loading. Metaphyseal bone mass increased with loading in young mice, but not in adult mice, whereas epiphyseal cancellous bone mass decreased with loading in both young and adult mice. In both age groups, articular cartilage thickness decreased, and subchondral cortical bone thickness increased in the posterior tibial plateau. Mice in both age groups developed periarticular osteophytes at the tibial plateau in response to the 9.0N load, but no osteophyte formation occurred in adult mice subjected to 4.5N peak loading. This noninvasive loading model permits dissection of temporal and topographic changes in cartilage and bone and will enable investigation of the efficacy of treatment interventions targeting joint biomechanics or biologic events that promote OA onset and progression. Copyright © 2013 by the American College of Rheumatology.

  7. In vivo cyclic compression causes cartilage degeneration and subchondral bone changes in mouse tibiae

    Science.gov (United States)

    Ko, Frank C.; Dragomir, Cecilia; Plumb, Darren A.; Goldring, Steven R.; Wright, Timothy M.; Goldring, Mary B.; van der Meulen, Marjolein C.H.

    2013-01-01

    Objectives Alterations in the mechanical loading environment in joints may have both beneficial and detrimental effects on articular cartilage and subchondral bone and subsequently influence the development of osteoarthritis (OA). We used an in vivo tibial loading model to investigate the adaptive responses of cartilage and bone to mechanical loading and to assess the influence of load level and duration. Methods We applied cyclic compression of 4.5 and 9.0N peak loads to the left tibia via the knee joint of adult (26-week-old) C57Bl/6 male mice for 1, 2, and 6 weeks. Only 9.0N loading was utilized in young (10-week-old) mice. The changes in articular cartilage and subchondral bone were analyzed by histology and microcomputed tomography. Results Loading promoted cartilage damage in both age groups, with increased damage severity dependent upon the duration of loading. Metaphyseal bone mass increased in the young mice, but not in the adult mice, whereas epiphyseal cancellous bone mass decreased with loading in both young and adult mice. Articular cartilage thickness decreased, and subchondral cortical bone thickness increased in the posterior tibial plateau in both age groups. Both age groups developed periarticular osteophytes at the tibial plateau in response to the 9.0N load, but no osteophyte formation occurred in adult mice subjected to 4.5N peak loading. Conclusion This non-invasive loading model permits dissection of temporal and topographical changes in cartilage and bone and will enable investigation of the efficacy of treatment interventions targeting joint biomechanics or biological events that promote OA onset and progression. PMID:23436303

  8. Co-expression of DKK-1 and Sclerostin in Subchondral Bone of the Proximal Femoral Heads from Osteoarthritic Hips.

    Science.gov (United States)

    Zarei, Allahdad; Hulley, Philippa A; Sabokbar, Afsie; Javaid, M Kassim

    2017-06-01

    Osteoarthritis (OA) is a progressively degenerative joint disease influenced by structural and metabolic factors. There is growing evidence that subchondral bone is involved in both symptomatic and structural progression in OA. The Wnt pathway has been implicated in the progression of OA but the expression and function of the Wnt inhibitors, Dikkopf (DKK-1) and sclerostin (SOST), are unclear. We examined the regional distribution of DKK-1 and SOST in subchondral bone of the femoral head using resection specimens following arthroplasty in patients presenting with end-stage OA. Cylindrical cores for immunohistochemistry were taken through midpoint of full thickness cartilage defect, partial cartilage defect, through base of osteophyte and through macroscopically normal cartilage. Subchondral bone was thickest in cores taken from regions with full cartilage defect and thinnest in cores taken from osteophyte regions. In subchondral bone, expression of both DKK-1 and SOST was observed exclusively in osteocytes. Expression was highest in subchondral bone in cores taken from regions with partial but not full thickness cartilage defects. DKK-1 but not SOST was expressed by chondrocytes in cores with macroscopically normal cartilage. The current study describes the regional cellular distribution of SOST and DKK-1 in hip OA. Expression was highest in the osteocytes in bone underlying partial thickness cartilage defects. It is however not clear if this is a cause or a consequence of alterations in the overlying cartilage. However, it is suggestive of an active remodeling process which might be targeted by disease-modifying agents.

  9. Prevalence of computed tomographic subchondral bone lesions in the scapulohumeral joint of 32 immature dogs with thoracic limb lameness.

    Science.gov (United States)

    Lande, Rachel; Reese, Shona L; Cuddy, Laura C; Berry, Clifford R; Pozzi, Antonio

    2014-01-01

    Osteochondrosis is a common developmental abnormality affecting the subchondral bone of immature, large breed dogs. The purpose of this retrospective study was to describe CT lesions detected in scapulohumeral joints of 32 immature dogs undergoing CT for thoracic limb lameness. Eight dogs (14 scapulohumeral joints) had arthroscopy following imaging. Thirteen dogs (19 scapulohumeral joints) were found to have CT lesions, including 10 dogs (16 scapulohumeral joints) with subchondral bone lesions and 3 dogs with enthesopathy of the supraspinatus tendon. In one dog, subchondral bone lesions appeared as large oval defects within the mid-aspect of the glenoid cavities, bilaterally. These lesions resembled osseous cyst-like lesions commonly identified in the horse. This is the first report of such a presentation of a subchondral bone lesion in the glenoid cavity of a dog. In all dogs, small, focal, round or linear lucent defects were visible within the cortical bone at the junction of the greater tubercle and intertubercular groove. These structures were thought to represent vascular channels. Findings from this study support the use of CT as an adjunct modality for the identification and characterization of scapulohumeral subchondral bone lesions in immature dogs with thoracic limb lameness. © 2013 American College of Veterinary Radiology.

  10. Spatial and temporal changes of subchondral bone proceed to articular cartilage degeneration in rats subjected to knee immobilization.

    Science.gov (United States)

    Xu, Lei; Li, Zhe; Lei, Lei; Zhou, Yue-Zhu; Deng, Song-Yun; He, Yong-Bin; Ni, Guo-Xin

    2016-03-01

    This study was aimed to investigate the spatial and temporal changes of subchondral bone and its overlying articular cartilage in rats following knee immobilization. A total of 36 male Wistar rats (11-13 months old) were assigned randomly and evenly into 3 groups. For each group, knee joints in 6 rats were immobilized unilaterally for 1, 4, or 8 weeks, respectively, while the remaining rats were allowed free activity and served as external control groups. For each animal, femurs at both sides were dissected after sacrificed. The distal part of femur was examined by micro-CT. Subsequently, femoral condyles were collected for further histological observation and analysis. For articular cartilage, significant changes were observed only at 4 and 8 weeks of immobilization. The thickness of articular cartilage and chondrocytes numbers decreased with time. However, significant changes in subchondral bone were defined by micro-CT following immobilization in a time-dependent manner. Immobilization led to a thinner and more porous subchondral bone plate, as well as a reduction in trabecular thickness and separation with a more rod-like architecture. Changes in subchondral bone occurred earlier than in articular cartilage. More importantly, immobilization-induced changes in subchondral bone may contribute, at least partially, to changes in its overlying articular cartilage. © 2016 Wiley Periodicals, Inc.

  11. Role of subchondral bone properties and changes in development of load-induced osteoarthritis in mice.

    Science.gov (United States)

    Adebayo, O O; Ko, F C; Wan, P T; Goldring, S R; Goldring, M B; Wright, T M; van der Meulen, M C H

    2017-12-01

    Animal models recapitulating post-traumatic osteoarthritis (OA) suggest that subchondral bone (SCB) properties and remodeling may play major roles in disease initiation and progression. Thus, we investigated the role of SCB properties and its effects on load-induced OA progression by applying a tibial loading model on two distinct mouse strains treated with alendronate (ALN). Cyclic compression was applied to the left tibia of 26-week-old male C57Bl/6 (B6, low bone mass) and FVB (high bone mass) mice. Mice were treated with ALN (26 μg/kg/day) or vehicle (VEH) for loading durations of 1, 2, or 6 weeks. Changes in articular cartilage and subchondral and epiphyseal cancellous bone were analyzed using histology and microcomputed tomography. FVB mice exhibited thicker cartilage, a thicker SCB plate, and higher epiphyseal cancellous bone mass and tissue mineral density than B6 mice. Loading induced cartilage pathology, osteophyte formation, and SCB changes; however, lower initial SCB mass and stiffness in B6 mice did not attenuate load-induced OA severity compared to FVB mice. By contrast, FVB mice exhibited less cartilage damage, and slower-growing and less mature osteophytes. In B6 mice, inhibiting bone remodeling via ALN treatment exacerbated cartilage pathology after 6 weeks of loading, while in FVB mice, inhibiting bone remodeling protected limbs from load-induced cartilage loss. Intrinsically lower SCB properties were not associated with attenuated load-induced cartilage loss. However, inhibiting bone remodeling produced differential patterns of OA pathology in animals with low compared to high SCB properties, indicating that these factors do influence load-induced OA progression. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  12. The effects of orally administered diacerein on cartilage and subchondral bone in an ovine model of osteoarthritis.

    Science.gov (United States)

    Hwa, S Y; Burkhardt, D; Little, C; Ghosh, P

    2001-04-01

    An ovine model of osteoarthritis (OA) induced by bilateral lateral meniscectomy (BLM) was used to evaluate in vivo effects of the slow acting antiarthritic drug diacerein (DIA) on degenerative changes in cartilage and subchondral bone of the operated joints. Twenty of 30 adult age matched Merino wethers were subjected to BLM in the knee joints and the remainder served as non-operated controls (NOC). Half of the BLM group (n = 10) were given DIA (25 mg/kg orally) daily for 3 mo, then 50 mg/kg daily for a further 6 mo. The remainder of the meniscectomized (MEN) group served as OA controls. Five DIA, 5 MEN, and 5 NOC animals were sacrificed at 3 mo and the remainder at 9 mo postsurgery. One knee joint of each animal was used for bone mineral density (BMD) studies. Osteochondral slabs from the lateral femoral condyle and lateral tibial plateau were cut from the contralateral joint and were processed for histological and histomorphometric examination to assess the cartilage and subchondral bone changes. No significant difference was observed in the modified Mankin scores for cartilage from the DIA and MEN groups at 3 or 9 mo. However, in animals treated with DIA, the thickness of cartilage (p = 0.05) and subchondral bone (p = 0.05) in the lesion (middle) zone of the lateral tibial plateau were decreased relative to the corresponding zone of the MEN group at 3 mo (p = 0.05). At 9 mo subchondral bone thickness in this zone remained the same as NOC but BMD, which included both subchondral and trabecular bone, was significantly increased relative to the NOC group (p = 0.01). In contrast, the subchondral bone thickness of the outer zone of lateral tibial plateau and lateral femoral condyle of both MEN and DIA groups increased after 9 mo, while BMD remained the same as in the NOC. DIA treatment of meniscectomized animals mediated selective responses of cartilage and subchondral bone to the altered mechanical stresses induced across the joints by this procedure. While

  13. Computed tomography of subchondral bone and osteophytes in hip osteoarthritis: the shape of things to come?

    Science.gov (United States)

    Turmezei, Tom D; Poole, Ken E S

    2011-01-01

    Bone is a fundamental component of the disordered joint homeostasis seen in osteoarthritis, a disease that has been primarily characterized by the breakdown of articular cartilage accompanied by local bone changes and a limited degree of joint inflammation. In this review we consider the role of computed tomography imaging and computational analysis in osteoarthritis research, focusing on subchondral bone and osteophytes in the hip. We relate what is already known in this area to what could be explored through this approach in the future in relation to both clinical research trials and the underlying cellular and molecular science of osteoarthritis. We also consider how this area of research could impact on our understanding of the genetics of osteoarthritis.

  14. Computed tomography of subchondral bone and osteophytes in hip osteoarthritis: the shape of things to come?

    Directory of Open Access Journals (Sweden)

    Tom D Turmezei

    2011-12-01

    Full Text Available Bone is a fundamental component of the disordered joint homeostasis seen in osteoarthritis, a disease that has been primarily characterised by the breakdown of articular cartilage accompanied by local bone changes and a limited degree of joint inflammation. In this review we consider the role of computed tomography imaging and computational analysis in osteoarthritis research, focusing on subchondral bone and osteophytes in the hip. We relate what is already known in this area to what could be explored through this approach in the future in relation to both clinical research trials and the underlying cellular and molecular science of osteoarthritis. We also consider how this area of research could impact on our understanding of the genetics of osteoarthritis.

  15. Early Subchondral Bone Loss at Arthritis Onset Predicted Late Arthritis Severity in a Rat Arthritis Model.

    Science.gov (United States)

    Courbon, Guillaume; Cleret, Damien; Linossier, Marie-Thérèse; Vico, Laurence; Marotte, Hubert

    2017-06-01

    Synovitis is usually observed before loss of articular function in rheumatoid arthritis (RA). In addition to the synovium and according to the "Inside-Outside" theory, bone compartment is also involved in RA pathogenesis. Then, we investigated time dependent articular bone loss and prediction of early bone loss to late arthritis severity on the rat adjuvant-induced arthritis (AIA) model. Lewis female rats were longitudinally monitored from arthritis induction (day 0), with early (day 10) and late (day 17) steps. Trabecular and cortical microarchitecture parameters of four ankle bones were assessed by microcomputed tomography. Gene expression was determined at sacrifice. Arthritis occurred at day 10 in AIA rats. At this time, bone erosions were detected on four ankle bones, with cortical porosity increase (+67%) and trabecular alterations including bone volume fraction (BV/TV: -13%), and trabecular thickness decrease. Navicular bone assessment was the most reproducible and sensitive. Furthermore, strong correlations were observed between bone alterations at day 10 and arthritis severity or bone loss at day 17, including predictability of day 10 BV/TV to day 17 articular index (R 2  = 0.76). Finally, gene expression at day 17 confirmed massive osteoclast activation and interestingly provided insights on strong activation of bone formation inhibitor markers at the joint level. In rat AIA, bone loss was already observed at synovitis onset and was predicted late arthritis severity. Our results reinforced the key role of subchondral bone in arthritis pathogenesis, in favour to the "Inside-Outside" theory. Mechanisms of bone loss in rat AIA involved resorption activation and formation inhibition changes. J. Cell. Physiol. 232: 1318-1325, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. MRI signal-based quantification of subchondral bone at the tibial plateau: a population study

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, James W. [Norfolk and Norwich University Hospital, Department of Radiology, Norwich (United Kingdom); Norfolk and Norwich University Hospital, Radiology Academy, Cotman Centre, Norwich (United Kingdom); Godley, Keith C.; Toms, Andoni P. [Norfolk and Norwich University Hospital, Department of Radiology, Norwich (United Kingdom)

    2014-11-15

    To determine whether differences in subchondral sclerosis at the tibial plateau could be detected with magnetic resonance (MR) imaging in two different age groups. This was a retrospective hypothesis-testing study. Thirty-two knees in group A (25-30 year olds) and 32 knees in group B (45-50 years old) were included. Participants had no MR features of osteoarthritis (OA). On coronal images, tibial articular cartilage thickness was measured, and regions of interest were created in the medial and lateral tibial plateau subchondral bone and in the tibial metaphysis. The measure of heterogeneity at the tibial plateaux was the ratio of the standard deviation of the signal in the medial/lateral compartment to the standard deviation of the signal in the metaphysis (ratio of standard deviations - RSS{sub medial}/RSS{sub lateral}). Differences between groups were assessed using unpaired Student's t-tests. Mean RSS{sub medial} was 2.61 (standard deviation, SD = 0.77) in group A and 2.97 (SD = 0.59) in group B. Mean RSS{sub lateral} in group A was 1.86 (SD = 0.63) and 1.89 (SD = 0.43) in group B. Mean total cartilage thickness (in mm) in group A was 3.38 (SD = 0.90) for the medial and 3.90 (SD = 1.09) for the lateral compartment and 3.44 (SD = 0.74) for the medial and 3.96 (SD = 0.96) for the lateral compartment in group B. The only parameter to show a statistically significant difference between groups was RSS{sub medial} (p = 0.04). A difference in medial subchondral bone sclerosis between two age groups was demonstrated in the absence of MR features of OA. This may represent the earliest OA change detectable on MR imaging. (orig.)

  17. High-grade MRI bone oedema is common within the surgical field in rheumatoid arthritis patients undergoing joint replacement and is associated with osteitis in subchondral bone

    DEFF Research Database (Denmark)

    McQueen, F M; Gao, A; Ostergaard, M

    2007-01-01

    OBJECTIVES: MRI bone oedema has been observed in early and advanced RA and may represent a cellular infiltrate (osteitis) in subchondral bone. We studied MRI scans from RA patients undergoing surgery, seeking to identify regions of bone oedema and examine its histopathological equivalent in resec...

  18. Molecular changes in articular cartilage and subchondral bone in the rat anterior cruciate ligament transection and meniscectomized models of osteoarthritis.

    Science.gov (United States)

    Pickarski, Maureen; Hayami, Tadashi; Zhuo, Ya; Duong, Le T

    2011-08-24

    Osteoarthritis (OA) is a debilitating, progressive joint disease. Similar to the disease progression in humans, sequential events of early cartilage degradation, subchondral osteopenia followed by sclerosis, and late osteophyte formation were demonstrated in the anterior cruciate ligament transection (ACLT) or ACLT with partial medial meniscectomy (ACLT + MMx) rat OA models. We describe a reliable and consistent method to examine the time dependent changes in the gene expression profiles in articular cartilage and subchondral bone. Local regulation of matrix degradation markers was demonstrated by a significant increase in mRNA levels of aggrecanase-1 and MMP-13 as early as the first week post-surgery, and expression remained elevated throughout the 10 week study. Immunohistochemistry confirmed MMP-13 expression in differentiated chondrocytes and synovial fibroblasts at week-2 and cells within osteophytes at week-10 in the surgically-modified-joints. Concomitant increases in chondrocyte differentiation markers, Col IIA and Sox 9, and vascular invasion markers, VEGF and CD31, peaked around week-2 to -4, and returned to Sham levels at later time points in both models. Indeed, VEGF-positive cells were found in the deep articular chondrocytes adjacent to subchondral bone. Osteoclastic bone resorption markers, cathepsin K and TRAP, were also elevated at week-2. Confirming bone resorption is an early local event in OA progression, cathepsin K positive osteoclasts were found invading the articular cartilage from the subchondral region at week 2. This was followed by late disease events, including subchondral sclerosis and osteophyte formation, as demonstrated by the upregulation of the osteoanabolic markers runx2 and osterix, toward week-4 to 6 post-surgery. In summary, this study demonstrated the temporal and cohesive gene expression changes in articular cartilage and subchondral bone using known markers of OA progression. The findings here support genome-wide profiling

  19. Molecular changes in articular cartilage and subchondral bone in the rat anterior cruciate ligament transection and meniscectomized models of osteoarthritis

    Directory of Open Access Journals (Sweden)

    Zhuo Ya

    2011-08-01

    Full Text Available Abstract Background Osteoarthritis (OA is a debilitating, progressive joint disease. Methods Similar to the disease progression in humans, sequential events of early cartilage degradation, subchondral osteopenia followed by sclerosis, and late osteophyte formation were demonstrated in the anterior cruciate ligament transection (ACLT or ACLT with partial medial meniscectomy (ACLT + MMx rat OA models. We describe a reliable and consistent method to examine the time dependent changes in the gene expression profiles in articular cartilage and subchondral bone. Results Local regulation of matrix degradation markers was demonstrated by a significant increase in mRNA levels of aggrecanase-1 and MMP-13 as early as the first week post-surgery, and expression remained elevated throughout the 10 week study. Immunohistochemistry confirmed MMP-13 expression in differentiated chondrocytes and synovial fibroblasts at week-2 and cells within osteophytes at week-10 in the surgically-modified-joints. Concomitant increases in chondrocyte differentiation markers, Col IIA and Sox 9, and vascular invasion markers, VEGF and CD31, peaked around week-2 to -4, and returned to Sham levels at later time points in both models. Indeed, VEGF-positive cells were found in the deep articular chondrocytes adjacent to subchondral bone. Osteoclastic bone resorption markers, cathepsin K and TRAP, were also elevated at week-2. Confirming bone resorption is an early local event in OA progression, cathepsin K positive osteoclasts were found invading the articular cartilage from the subchondral region at week 2. This was followed by late disease events, including subchondral sclerosis and osteophyte formation, as demonstrated by the upregulation of the osteoanabolic markers runx2 and osterix, toward week-4 to 6 post-surgery. Conclusions In summary, this study demonstrated the temporal and cohesive gene expression changes in articular cartilage and subchondral bone using known markers of

  20. Technical Report: Correlation Between the Repair of Cartilage and Subchondral Bone in an Osteochondral Defect Using Bilayered, Biodegradable Hydrogel Composites.

    Science.gov (United States)

    Lu, Steven; Lam, Johnny; Trachtenberg, Jordan E; Lee, Esther J; Seyednejad, Hajar; van den Beucken, Jeroen J J P; Tabata, Yasuhiko; Kasper, F Kurtis; Scott, David W; Wong, Mark E; Jansen, John A; Mikos, Antonios G

    2015-12-01

    The present work investigated correlations between cartilage and subchondral bone repair, facilitated by a growth factor-delivering scaffold, in a rabbit osteochondral defect model. Histological scoring indices and microcomputed tomography morphological parameters were used to evaluate cartilage and bone repair, respectively, at 6 and 12 weeks. Correlation analysis revealed significant associations between specific cartilage indices and subchondral bone parameters that varied with location in the defect (cortical vs. trabecular region), time point (6 vs. 12 weeks), and experimental group (insulin-like growth factor-1 only, bone morphogenetic protein-2 only, or both growth factors). In particular, significant correlations consistently existed between cartilage surface regularity and bone quantity parameters. Overall, correlation analysis between cartilage and bone repair provided a fuller understanding of osteochondral repair and can help drive informed studies for future osteochondral regeneration strategies.

  1. ALPHA-CTX is associated with subchondral bone turnover and predicts progression of joint space narrowing and osteophytes in osteoarthritis

    Science.gov (United States)

    Huebner, Janet L; Bay-Jensen, Anne C; Huffman, Kim M; He, Yi; Leeming, Diana J; McDaniel, Gary E; Karsdal, Morten A; Kraus, Virginia B

    2014-01-01

    Objective To evaluate joint tissue remodeling, with urinary collagen biomarkers, uALPHA CTX and uCTXII, and their association with osteoarthritis (OA) severity, progression, and localized knee bone turnover. Methods Participants (N=149) with symptomatic and radiographic knee OA underwent fixed flexion knee radiography at baseline and 3 years, and late-phase bone scintigraphy of both knees at baseline, scored semi-quantitatively for osteophyte (OST) and joint space narrowing (JSN) severity and uptake intensity with scores summed across knees. Urinary concentrations of ALPHA CTX and CTXII were determined by ELISA. Immunohistochemistry of human OA knees was performed to localize the joint tissue origin of the biomarker epitopes. Results uALPHA CTX correlated strongly with intensity of bone scintigraphic uptake, and JSN and OST progression (risk ratio=13.2 and 3, respectively). uCTXII was strongly associated with intensity of bone scintigraphic uptake, with JSN and OST severity, and OA progression based on OST. uALPHA CTX localized primarily to high bone turnover areas in subchondral bone; CTXII localized to the bone-cartilage interface, the tidemark, and damaged articular cartilage. Conclusion Baseline uALPHA CTX, localized to high turnover areas of subchondral bone, was associated with dynamic bone turnover of knees signified by scintigraphy, and progression of both OST and JSN. uCTXII correlated with JSN and OST severity, and progression of OST. To our knowledge, this represents the first report of serological markers reflecting subchondral bone turnover. These collagen markers may be useful for non-invasive detection and quantification of active subchondral bone turnover and joint remodeling in knee OA. PMID:24909851

  2. Third metacarpal condylar fatigue fractures in equine athletes occur within previously modelled subchondral bone.

    Science.gov (United States)

    Whitton, R Christopher; Trope, Gareth D; Ghasem-Zadeh, Ali; Anderson, Garry A; Parkin, Timothy D H; Mackie, Eleanor J; Seeman, Ego

    2010-10-01

    Bone modelling and remodelling reduce the risk of fatigue fractures; the former by adapting bone to its loading circumstances, the latter by replacing fatigued bone. Remodelling transiently increases porosity because of the normal delay in onset of the formation phase of the remodelling sequence. Protracted intense loading suppresses remodelling leaving modelling as the only means of maintaining bone strength. We therefore hypothesized that race horses with fatigue fractures of the distal third metacarpal bone (MC3) will have reduced porosity associated with suppressed remodelling while continued adaptive modelling will result in higher volume fraction (BV/TV) at this site. Using high resolution peripheral quantitative computed tomography (HR-pQCT), we measured the distal aspect of the MC3 obtained at postmortem from 13 thoroughbred race horses with condylar fractures of the MC3 (cases), 8 horses without fractures (training controls), 14 horses with a fracture at another site (fractured controls) and 9 horses resting from training (resting controls). Porosity of the subchondral bone of MC3 was lower in cases than resting controls (12±1.4% vs. 18±1.6%, P=0.017) although areas of focal porosity were observed adjacent to fractures in 6/13 horses. BV/TV of the distal metacarpal epiphysis tended to be higher in horses with condylar fractures (0.79±0.015) than training controls (0.74±0.019, P=0.070), but also higher in controls with a fracture elsewhere (0.79±0.014) than the training controls (0.74±0.019, P=0.040). BV/TV was higher in horses over three years of age than those aged two or three years (0.79±0.01 vs. 0.74±0.01, P=0.016). All metacarpal condylar fractures occurred within focal areas of high BV/TV. We infer that intense training in equine athletes suppresses remodelling of third metacarpal subchondral bone limiting damage repair while modelling increases regional bone volume in an attempt to minimise local stresses but may fail to offset bone

  3. Perfusion of subchondral bone marrow in knee osteoarthritis: A dynamic contrast-enhanced magnetic resonance imaging preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Budzik, Jean-François, E-mail: Budzik.jean-francois@ghicl.net [Lille Catholic Hospitals, Imaging Department, Lille Catholic University, Lille (France); PMOI Physiopathology of Inflammatory Bone Diseases, EA 4490, Lille (France); Ding, Juliette, E-mail: Ding.juliette@gmail.com [Lille Catholic Hospitals, Imaging Department, Lille Catholic University, Lille (France); Norberciak, Laurène, E-mail: Norberciak.Laurene@ghicl.net [Lille Catholic Hospitals, Biostatistics Department, Lille Catholic University, Lille (France); Pascart, Tristan, E-mail: Pascart.tristan@ghicl.net [Lille Catholic Hospitals, Rheumatology Department, Lille Catholic University, Lille (France); Toumi, Hechmi, E-mail: hechmi.toumi@univ-orleans.fr [EA4708 I3MTO, Orleans Regional Hospital, University of Orleans, Orleans (France); Verclytte, Sébastien, E-mail: Verclytte.Sebastien@ghicl.net [Lille Catholic Hospitals, Imaging Department, Lille Catholic University, Lille (France); Coursier, Raphaël, E-mail: Coursier.Raphael@ghicl.net [Lille Catholic Hospitals, Orthopaedic Surgery Department, Lille Catholic University, Lille (France)

    2017-03-15

    The role of inflammation in the pathogenesis of osteoarthritis is being given major interest, and inflammation is closely linked with vascularization. It was recently demonstrated that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) could identify the subchondral bone marrow vascularization changes occurring in osteoarthritis in animals. These changes appeared before cartilage lesions were visible and were correlated with osteoarthritis severity. Thus the opportunity to obtain an objective assessment of bone vascularization in non-invasive conditions in humans might help better understanding osteoarthritis pathophysiology and finding new biomarkers. We hypothesized that, as in animals, DCE-MRI has the ability to identify subchondral bone marrow vascularization changes in human osteoarthritis. We performed knee MRI in 19 patients with advanced knee osteoarthritis. We assessed subchondral bone marrow vascularization in medial and lateral femorotibial compartments with DCE-MRI and graded osteoarthritis lesions on MR images. Statistical analysis assessed intra- and inter-observer agreement, compared DCE-MRI values between the different subchondral zones, and sought for an influence of age, sex, body mass index, and osteoarthritis garde on these values. The intra- and inter-observer agreement for DCE-MRI values were excellent. These values were significantly higher in the femorotibial compartment the most affected by osteoarthritis, both in femur and tibia (p < 0.0001) and were significantly and positively correlated with cartilage lesions (p = 0.02) and bone marrow oedema grade (p < 0.0001) after adjustment. We concluded that, as in animals, subchondral bone marrow vascularization changes assessed with DCE-MRI were correlated with osteoarthritis severity in humans.

  4. Perfusion of subchondral bone marrow in knee osteoarthritis: A dynamic contrast-enhanced magnetic resonance imaging preliminary study

    International Nuclear Information System (INIS)

    Budzik, Jean-François; Ding, Juliette; Norberciak, Laurène; Pascart, Tristan; Toumi, Hechmi; Verclytte, Sébastien; Coursier, Raphaël

    2017-01-01

    The role of inflammation in the pathogenesis of osteoarthritis is being given major interest, and inflammation is closely linked with vascularization. It was recently demonstrated that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) could identify the subchondral bone marrow vascularization changes occurring in osteoarthritis in animals. These changes appeared before cartilage lesions were visible and were correlated with osteoarthritis severity. Thus the opportunity to obtain an objective assessment of bone vascularization in non-invasive conditions in humans might help better understanding osteoarthritis pathophysiology and finding new biomarkers. We hypothesized that, as in animals, DCE-MRI has the ability to identify subchondral bone marrow vascularization changes in human osteoarthritis. We performed knee MRI in 19 patients with advanced knee osteoarthritis. We assessed subchondral bone marrow vascularization in medial and lateral femorotibial compartments with DCE-MRI and graded osteoarthritis lesions on MR images. Statistical analysis assessed intra- and inter-observer agreement, compared DCE-MRI values between the different subchondral zones, and sought for an influence of age, sex, body mass index, and osteoarthritis garde on these values. The intra- and inter-observer agreement for DCE-MRI values were excellent. These values were significantly higher in the femorotibial compartment the most affected by osteoarthritis, both in femur and tibia (p < 0.0001) and were significantly and positively correlated with cartilage lesions (p = 0.02) and bone marrow oedema grade (p < 0.0001) after adjustment. We concluded that, as in animals, subchondral bone marrow vascularization changes assessed with DCE-MRI were correlated with osteoarthritis severity in humans.

  5. Quantitative evaluation of subchondral bone injury of the plantaro-lateral condyles of the third metatarsal bone in Thoroughbred horses identified using nuclear scintigraphy: 48 cases.

    Science.gov (United States)

    Parker, R A; Bladon, B M; Parkin, T D H; Fraser, B S L

    2010-09-01

    Increased radio-isotope uptake (IRU) in the subchondral bone of the plantaro-lateral condyle of the third metatarsus (MTIII) is a commonly reported scintigraphic finding and potential cause of lameness in UK Thoroughbred racehorses in training and has not been fully documented. To characterise lameness attributable to IRU of the subchondral bone of MTIII, compare the scintigraphic findings of these horses with a normal population and evaluate the use of scintigraphy as an indicator of prognosis. IRU will be in significantly higher in horses with subchondral bone injury and will be related to prognosis and future racing performance. Data were analysed from 48 horses in which subchondral bone injury of the plantaro-lateral condyle of MTIII had been diagnosed using nuclear scintigraphy and that met the inclusion criteria. Data recorded included age, sex, trainer, racing discipline, lameness assessment, treatment regimes, radiographic and scintigraphic findings, response to diagnostic analgesia where performed and racing performance pre- and post diagnosis. Region of interest (ROI) counts were obtained for the plantar condyle and the mid diaphysis from the latero-medial view, the ratio calculated and then compared with a control group of clinically unaffected horses. The mean condyle mid-diaphysis ROI ratio was significantly (PThoroughbred racehorses. Nuclear scintigraphy is a useful diagnostic imaging modality in the detection of affected horses but is a poor indicator of prognosis for the condition. Better understanding of the clinical manifestations, diagnosis of and prognosis for subchondral bone injury will benefit the Thoroughbred industry in the UK.

  6. Distribution of vitamin K2 in subchondral bone in osteoarthritic knee joints.

    Science.gov (United States)

    Ishii, Yoshinori; Noguchi, Hideo; Takeda, Mitsuhiro; Sato, Junko; Yamamoto, Noriaki; Wakabayashi, Hiroyuki; Kanda, Junkichi; Toyabe, Shin-ichi

    2013-08-01

    Vitamin K may have multiple effects on articular cartilage and subchondral bone that could modulate the pathogenesis of osteoarthritis (OA). The purpose of this study was to evaluate the distribution of vitamin K2 in harvested bones obtained during total knee arthroplasty in knee OA patients. High-performance liquid chromatography was used to measure vitamin K2 in harvested bones obtained during 58 TKA procedures. Vitamin K2 levels were analysed in the medial (FM) and lateral (FL) femoral condyles and in the medial (TM) and lateral (TL) tibial condyles. There was significantly more vitamin K2 in the lateral femoral and tibial condyles than in the corresponding medial condyles (FL vs. FM, p K2 in the FL than in the TL (p = 0.003), and in the FM, vitamin K2 levels were higher than those of the TM, although this was not significant (n.s.). There were no significant differences in vitamin K2 levels in men versus women nor was there a significant correlation with age. This study suggested that vitamin K2 might affect bone turnover since medial condyles showing advanced OA had lower vitamin K2 levels, while lateral condyles showing less advanced OA contained more vitamin K2. Gender and age were not correlated with vitamin K2 localization. All cases had Grade IV OA, and this study suggested that OA grade might be important in controlling the vitamin K2 levels in human bones.

  7. Quantitative ultrasound imaging detects degenerative changes in articular cartilage surface and subchondral bone

    International Nuclear Information System (INIS)

    Saarakkala, Simo; Laasanen, Mikko S; Jurvelin, Jukka S; Toeyraes, Juha

    2006-01-01

    Previous studies have suggested that quantitative ultrasound imaging could sensitively diagnose degeneration of the articular surface and changes in the subchondral bone during the development of osteoarthrosis (OA). We have recently introduced a new parameter, ultrasound roughness index (URI), for the quantification of cartilage surface roughness, and successfully tested it with normal and experimentally degraded articular surfaces. In this in vitro study, the applicability of URI was tested in bovine cartilage samples with spontaneously developed tissue degeneration. Simultaneously, we studied the sensitivity of quantitative ultrasound imaging to detect degenerative changes in the cartilage-bone interface. For reference, histological degenerative grade of the cartilage samples was determined. Mechanical reference measurements were also conducted. Cartilage surface roughness (URI) was significantly (p < 0.05) higher in histologically degenerated samples with inferior mechanical properties. Ultrasound reflection at the cartilage-bone interface was also significantly (p < 0.05) increased in degenerated samples. Furthermore, it was quantitatively confirmed that ultrasound attenuation in the overlying cartilage significantly affects the measured ultrasound reflection values from the cartilage-bone interface. To conclude, the combined ultrasound measurement of the cartilage surface roughness and ultrasound reflection at the cartilage-bone interface complement each other, and may together enable more sensitive and quantitative diagnosis of early OA or follow up after surgical cartilage repair

  8. Linear signal hyperintensity adjacent to the subchondral bone plate at the knee on T2-weighted fat-saturated sequences: imaging aspects and association with structural lesions

    Energy Technology Data Exchange (ETDEWEB)

    Gondim Teixeira, Pedro Augusto; Balaj, Clemence [CHU Hopital Central, Service D' Imagerie Guilloz, Nancy (France); Universite de Lorraine, IADI, UMR S 947, Nancy (France); Marie, Beatrice [CHU Hopital Central, Service d' Anatomo-Pathologie, Nancy (France); Lecocq, Sophie; Louis, Matthias; Blum, Alain [CHU Hopital Central, Service D' Imagerie Guilloz, Nancy (France); Braun, Marc [CHU Hopital Central, Service de Neuroradiologie, Nancy (France)

    2014-11-15

    To describe the association between linear T2 signal abnormalities in the subchondral bone and structural knee lesions. MR studies of patients referred for the evaluation of knee pain were retrospectively evaluated and 133 of these patients presented bone marrow edema pattern (BMEP) (study group) and while 61 did not (control group). The presence of linear anomalies of the subchondral bone on T2-weighted fat-saturated sequences was evaluated. The findings were correlated to the presence of structural knee lesions and to the duration of the patient's symptoms. Histologic analysis of a cadaveric specimen was used for anatomic correlation. Linear T2 hyperintensities at the subchondral bone were present in 41 % of patients with BMEP. None of the patients in the control group presented this sign. When a subchondral linear hyperintensity was present, the prevalence of radial or root tears was high and that of horizontal tears was low (71.4 and 4.8 %, respectively). Sixty-nine percent of the patients with a subchondral insufficiency fracture presented a subchondral linear hyperintensity. It was significantly more prevalent in patients with acute or sub-acute symptoms (p < 0.0001). The studied linear T2 hyperintensity is located at the subchondral spongiosa and can be secondary to local or distant joint injuries. Its presence should evoke acute and sub-acute knee injuries. This sign is closely related to subchondral insufficiency fractures and meniscal tears with a compromise in meniscal function. (orig.)

  9. A systematic review of the relationship between subchondral bone features, pain and structural pathology in peripheral joint osteoarthritis.

    Science.gov (United States)

    Barr, Andrew J; Campbell, T Mark; Hopkinson, Devan; Kingsbury, Sarah R; Bowes, Mike A; Conaghan, Philip G

    2015-08-25

    Bone is an integral part of the osteoarthritis (OA) process. We conducted a systematic literature review in order to understand the relationship between non-conventional radiographic imaging of subchondral bone, pain, structural pathology and joint replacement in peripheral joint OA. A search of the Medline, EMBASE and Cochrane library databases was performed for original articles reporting association between non-conventional radiographic imaging-assessed subchondral bone pathologies and joint replacement, pain or structural progression in knee, hip, hand, ankle and foot OA. Each association was qualitatively characterised by a synthesis of the data from each analysis based upon study design, adequacy of covariate adjustment and quality scoring. In total 2456 abstracts were screened and 139 papers were included (70 cross-sectional, 71 longitudinal analyses; 116 knee, 15 hip, six hand, two ankle and involved 113 MRI, eight DXA, four CT, eight scintigraphic and eight 2D shape analyses). BMLs, osteophytes and bone shape were independently associated with structural progression or joint replacement. BMLs and bone shape were independently associated with longitudinal change in pain and incident frequent knee pain respectively. Subchondral bone features have independent associations with structural progression, pain and joint replacement in peripheral OA in the hip and hand but especially in the knee. For peripheral OA sites other than the knee, there are fewer associations and independent associations of bone pathologies with these important OA outcomes which may reflect fewer studies; for example the foot and ankle were poorly studied. Subchondral OA bone appears to be a relevant therapeutic target. PROSPERO registration number: CRD 42013005009.

  10. Influence of meniscus on cartilage and subchondral bone features of knees from older individuals: A cadaver study.

    Science.gov (United States)

    Touraine, Sébastien; Bouhadoun, Hamid; Engelke, Klaus; Laredo, Jean Denis; Chappard, Christine

    2017-01-01

    Cartilage and subchondral bone form a functional unit. Here, we aimed to examine the effect of meniscus coverage on the characteristics of this unit in knees of older individuals. We assessed the hyaline cartilage, subchondral cortical plate (SCP), and subchondral trabecular bone in areas covered or uncovered by the meniscus from normal cadaver knees (without degeneration). Bone cores harvested from the medial tibial plateau at locations uncovered (central), partially covered (posterior), and completely covered (peripheral) by the meniscus were imaged by micro-CT. The following were measured on images: cartilage volume (Cart.Vol, mm3) and thickness (Cart.Th, mm); SCP thickness (SCP.Th, μm) and porosity (SCP.Por, %); bone volume to total volume fraction (BV/TV, %); trabecular thickness (Tb.Th, μm), spacing (Tb.Sp, μm), and number (Tb.N, 1/mm); structure model index (SMI); trabecular pattern factor (Tb.Pf); and degree of anisotropy (DA). Among the 28 specimens studied (18 females) from individuals with mean age 82.8±10.2 years, cartilage and SCP were thicker at the central site uncovered by the meniscus than the posterior and peripheral sites, and Cart.Vol was greater. SCP.Por was highest in posterior samples. In the upper 1-5 mm of subchondral bone, central samples were characterized by higher values for BV/TV, Tb.N, Tb.Th, and connectivity (Tb.Pf), a more plate-like trabecular structure and lower anisotropy than with other samples. Deeper down, at 6-10 mm, the differences were slightly higher for Tb.Th centrally, DA peripherally and SMI posteriorly. The coverage or not by meniscus in the knee of older individuals is significantly associated with Cart.Th, SCP.Th, SCP.Por and trabecular microarchitectural parameters in the most superficial 5 mm and to a lesser extent the deepest area of subchondral trabecular bone. These results suggest an effect of differences in local loading conditions. In subchondral bone uncovered by the meniscus, the trabecular architecture

  11. Influence of meniscus on cartilage and subchondral bone features of knees from older individuals: A cadaver study.

    Directory of Open Access Journals (Sweden)

    Sébastien Touraine

    Full Text Available Cartilage and subchondral bone form a functional unit. Here, we aimed to examine the effect of meniscus coverage on the characteristics of this unit in knees of older individuals.We assessed the hyaline cartilage, subchondral cortical plate (SCP, and subchondral trabecular bone in areas covered or uncovered by the meniscus from normal cadaver knees (without degeneration. Bone cores harvested from the medial tibial plateau at locations uncovered (central, partially covered (posterior, and completely covered (peripheral by the meniscus were imaged by micro-CT. The following were measured on images: cartilage volume (Cart.Vol, mm3 and thickness (Cart.Th, mm; SCP thickness (SCP.Th, μm and porosity (SCP.Por, %; bone volume to total volume fraction (BV/TV, %; trabecular thickness (Tb.Th, μm, spacing (Tb.Sp, μm, and number (Tb.N, 1/mm; structure model index (SMI; trabecular pattern factor (Tb.Pf; and degree of anisotropy (DA.Among the 28 specimens studied (18 females from individuals with mean age 82.8±10.2 years, cartilage and SCP were thicker at the central site uncovered by the meniscus than the posterior and peripheral sites, and Cart.Vol was greater. SCP.Por was highest in posterior samples. In the upper 1-5 mm of subchondral bone, central samples were characterized by higher values for BV/TV, Tb.N, Tb.Th, and connectivity (Tb.Pf, a more plate-like trabecular structure and lower anisotropy than with other samples. Deeper down, at 6-10 mm, the differences were slightly higher for Tb.Th centrally, DA peripherally and SMI posteriorly.The coverage or not by meniscus in the knee of older individuals is significantly associated with Cart.Th, SCP.Th, SCP.Por and trabecular microarchitectural parameters in the most superficial 5 mm and to a lesser extent the deepest area of subchondral trabecular bone. These results suggest an effect of differences in local loading conditions. In subchondral bone uncovered by the meniscus, the trabecular architecture

  12. Bone cysts after osteochondral allograft repair of cartilage defects in goats suggest abnormal interaction between subchondral bone and overlying synovial joint tissues.

    Science.gov (United States)

    Pallante-Kichura, Andrea L; Cory, Esther; Bugbee, William D; Sah, Robert L

    2013-11-01

    The efficacy of osteochondral allografts (OCAs) may be affected by osseous support of the articular cartilage, and thus affected by bone healing and remodeling in the OCA and surrounding host. Bone cysts, and their communication pathways, may be present in various locations after OCA insertion and reflect distinct pathogenic mechanisms. Previously, we analyzed the effect of OCA storage (FRESH, 4°C/14d, 4°C/28d, FROZEN) on cartilage quality in fifteen adult goats after 12months in vivo. The objectives of this study were to further analyze OCAs and contralateral non-operated (Non-Op) CONTROLS from the medial femoral condyle to (1) determine the effect of OCA storage on local subchondral bone (ScB) and trabecular bone (TB) structure, (2) characterize the location and structure of bone cysts and channels, and (3) assess the relationship between cartilage and bone properties. (1) Overall bone structure after OCAs was altered compared to Non-Op, with OCA samples displaying bone cysts, ScB channels, and ScB roughening. ScB BV/TV in FROZEN OCAs was lower than Non-Op and other OCAs. TB BV/TV in FRESH, 4°C/14d, and 4°C/28d OCAs did not vary compared to Non-Op, but BS/TV was lower. (2) OCAs contained "basal" cysts, localized to deeper regions, some "subchondral" cysts, localized near the bone-cartilage interface, and some ScB channels. TB surrounding basal cysts exhibited higher BV/TV than Non-Op. (3) Basal cysts occurred (a) in isolation, (b) with subchondral cysts and ScB channels, (c) with ScB channels, or (d) with subchondral cysts, ScB channels, and ScB erosion. Deterioration of cartilage gross morphology was strongly associated with abnormal μCT bone structure. Evidence of cartilage-bone communication following OCA repair may favor fluid intrusion as a mechanism for subchondral cyst formation, while bone resorption at the graft-host interface without affecting overall bone and cartilage structure may favor bony contusion mechanism for basal cyst formation. These

  13. A role for subchondral bone changes in the process of osteoarthritis; a micro-CT study of two canine models.

    Science.gov (United States)

    Sniekers, Yvonne H; Intema, Femke; Lafeber, Floris P J G; van Osch, Gerjo J V M; van Leeuwen, Johannes P T M; Weinans, Harrie; Mastbergen, Simon C

    2008-02-12

    This study evaluates changes in peri-articular bone in two canine models for osteoarthritis: the groove model and the anterior cruciate ligament transection (ACLT) model. Evaluation was performed at 10 and 20 weeks post-surgery and in addition a 3-weeks time point was studied for the groove model. Cartilage was analysed, and architecture of the subchondral plate and trabecular bone of epiphyses was quantified using micro-CT. At 10 and 20 weeks cartilage histology and biochemistry demonstrated characteristic features of osteoarthritis in both models (very mild changes at 3 weeks). The groove model presented osteophytes only at 20 weeks, whereas the ACLT model showed osteophytes already at 10 weeks. Trabecular bone changes in the groove model were small and not consistent. This contrasts the ACLT model in which bone volume fraction was clearly reduced at 10 and 20 weeks (15-20%). However, changes in metaphyseal bone indicate unloading in the ACLT model, not in the groove model. For both models the subchondral plate thickness was strongly reduced (25-40%) and plate porosity was strongly increased (25-85%) at all time points studied. These findings show differential regulation of subchondral trabecular bone in the groove and ACLT model, with mild changes in the groove model and more severe changes in the ACLT model. In the ACLT model, part of these changes may be explained by unloading of the treated leg. In contrast, subchondral plate thinning and increased porosity were very consistent in both models, independent of loading conditions, indicating that this thinning is an early response in the osteoarthritis process.

  14. Changes in subchondral bone mineral density and collagen matrix organization in growing horses.

    Science.gov (United States)

    Holopainen, Jaakko T; Brama, Pieter A J; Halmesmäki, Esa; Harjula, Terhi; Tuukkanen, Juha; van Weeren, P René; Helminen, Heikki J; Hyttinen, Mika M

    2008-12-01

    The effects of growth and maturation on the mineral deposition and the collagen framework of equine subchondral bone (SCB) were studied. Osteochondral specimens (diameter 6 mm) from the left metacarpophalangeal joint of 5-(n=8), 11-(n=8) and 18-month-old (n=6) horses were investigated at two differently loaded sites (Site 1 (S1): intermittent peak loading; Site 2 (S2): habitual loading). The SCB mineral density (BMD) was measured with peripheral quantitative computer tomography (pQCT), and the data were adjusted against the volume fraction (Vv) of the bone extracellular matrix (ECM). Polarised light microscopy (PLM) was used to analyze the Vv, the collagen fibril parallelism index and the orientation angle distribution in two fractions (1 mm/fraction) beneath the osteochondral junction of the SCB. PLM analysis was made along two randomly selected perpendicularly oriented vertical sections to measure the tissue anisotropy in the x-, y-, and z-directions. The BMD of SCB at S1 and S2 increased significantly during maturation. At the same time, the Vv of the ECM increased even more. This meant that the Vv-adjusted BMD decreased. There were no significant differences between sites. The basic collagen fibril framework of SCB seems to be established already at the age of 5 months. During maturation, the extracellular matrix underwent a decrease in collagen fibril parallelism but no changes in collagen orientation. The variation was negligible in the collagen network estimates in the two section planes. Growth and maturation induce significant changes in the equine SCB. The BMD increase in SCB is primarily due to the growth of bone volume and not to any increase in mineral deposition. An increase in weight-bearing appears to greatly affect the BMD and the volume of the extracellular matrix. Growth and maturation induce a striking change in collagen fibril parallelism but not in fibril orientation. The structural anisotropy of the subchondral bone is significant along the

  15. Chitosan-glycerol phosphate/blood implants elicit hyaline cartilage repair integrated with porous subchondral bone in microdrilled rabbit defects.

    Science.gov (United States)

    Hoemann, C D; Sun, J; McKee, M D; Chevrier, A; Rossomacha, E; Rivard, G-E; Hurtig, M; Buschmann, M D

    2007-01-01

    We have previously shown that microfractured ovine defects are repaired with more hyaline cartilage when the defect is treated with in situ-solidified implants of chitosan-glycerol phosphate (chitosan-GP) mixed with autologous whole blood. The objectives of this study were (1) to characterize chitosan-GP/blood clots in vitro, and (2) to develop a rabbit marrow stimulation model in order to determine the effects of the chitosan-GP/blood implant and of debridement on the formation of incipient cartilage repair tissue. Blood clots were characterized by histology and in vitro clot retraction tests. Bilateral 3.5 x 4 mm trochlear defects debrided into the calcified layer were pierced with four microdrill holes and filled with a chitosan-GP/blood implant or allowed to bleed freely as a control. At 1 day post-surgery, initial defects were characterized by histomorphometry (n=3). After 8 weeks of repair, osteochondral repair tissues between or through the drill holes were evaluated by histology, histomorphometry, collagen type II expression, and stereology (n=16). Chitosan-GP solutions structurally stabilized the blood clots by inhibiting clot retraction. Treatment of drilled defects with chitosan-GP/blood clots led to the formation of a more integrated and hyaline repair tissue above a more porous and vascularized subchondral bone plate compared to drilling alone. Correlation analysis of repair tissue between the drill holes revealed that the absence of calcified cartilage and the presence of a porous subchondral bone plate were predictors of greater repair tissue integration with subchondral bone (Phyaline and integrated repair tissue associated with a porous subchondral bone replete with blood vessels. Concomitant regeneration of a vascularized bone plate during cartilage repair could provide progenitors, anabolic factors and nutrients that aid in the formation of hyaline cartilage.

  16. Chondroitin sulfate and glucosamine in the cartilage and subchondral bone repair of dogs - Histological findings

    Directory of Open Access Journals (Sweden)

    R.B. Eleotério

    2015-04-01

    Full Text Available Chondroitin and glucosamine sulfate nutraceuticals are commonly used in the management of degenerative articular disease in veterinary routine. However, there are controversies on the contribution of these substances to articular cartilage. The purpose of this study was to evaluate the efficiency of a chondroitin and glucosamine sulfate-based veterinary nutraceutical on the repair of an induced osteochondral defect in a dog femoral condyle, by macroscopic, histological and histomorphometric analyses. The nutraceutical was orally administered the day following injury induction, every 24 hours (treated group, TG, n=24, compared with animals that did not receive the product (control group, CG, n=24. Six animals per group were anaesthetized for sample collection at 15, 30, 60 and 90 days after surgery. At 15 days, defects were macroscopically filled with red-pinkish tissue. After 30 days, whitish color tissue was observed, both in TG and CG animals, with firmer consistency to touch at 60 and 90 postoperative days. Histological analysis demonstrated that, in both groups, there was initial blood clot formation, which was subsequently substituted by a fibrin net, with capillary proliferation from the adjacent bone marrow and infiltration of mesenchymal cells in clot periphery. As cellular differentiation developed, repair tissue presented a fibrocartilage aspect most of the time, and new subchondral bone formation occurred in the deepest area corresponding to the defect. Histomorphometry suggested that the nutraceutical did not favor the articular cartilage repair process. It was concluded that nutraceutical did not significantly influence chondrocytes proliferation or hyaline architecture restoration.

  17. Cartilage damage involving extrusion of mineralisable matrix from the articular calcified cartilage and subchondral bone

    Directory of Open Access Journals (Sweden)

    A Boyde

    2011-05-01

    Full Text Available Arthropathy of the distal articular surfaces of the third metacarpal (Mc3 and metatarsal (Mt3 bones in the Thoroughbred racehorse (Tb is a natural model of repetitive overload arthrosis. We describe a novel pathology that affects the articular calcified cartilage (ACC and subchondral bone (SCB and which is associated with hyaline articular cartilage degeneration. Parasagittal slices cut from the palmar quadrant of the distal condyles of the left Mc3/Mt3 of 39 trained Tbs euthanased for welfare reasons were imaged by point projection microradiography, and backscattered electron (BSE scanning electron microscopy (SEM, light microscopy, and confocal scanning light microscopy. Mechanical properties were studied by nanoindentation. Data on the horses' training and racing career were also collected. Highly mineralised projections were observed extending from cracks in the ACC mineralising front into the hyaline articular cartilage (HAC up to two-thirds the thickness of the HAC, and were associated with focal HAC surface fibrillation directly overlying their site. Nanoindentation identified this extruded matrix to be stiffer than any other mineralised phase in the specimen by a factor of two. The presence of projections was associated with a higher cartilage Mankin histology score (P < 0.02 and increased amounts of gross cartilage loss pathologically on the condyle (P < 0.02. Presence of projections was not significantly associated with: total number of racing seasons, age of horse, amount of earnings, number of days in training, total distance galloped in career, or presence of wear lines.

  18. The Effects of Bone Remodeling Inhibition by Alendronate on Three-Dimensional Microarchitecture of Subchondral Bone Tissues in Guinea Pig Primary Osteoarthrosis

    DEFF Research Database (Denmark)

    Ding, Ming

    2008-01-01

    We assessed whether increase of subchondral bone density enhances cartilage stress during impact loading, leading to progressive cartilage degeneration and accelerated osteoarthrosis (OA) progression. Sixty-six male guinea pigs were randomly divided into six groups. During a 9-week treatment period...

  19. The effects of bone remodeling inhibition by alendronate on 3-D microarchitecture of subchondral bone tissues in guinea pig primary osteoarthrosis

    DEFF Research Database (Denmark)

    Ding, Ming; Danielsen, Carl Christian; Hvid, Ivan

    2008-01-01

    We assess whether increase of subchondral bone density enhances cartilage stress during impact loading leading to progressive cartilage degeneration and accelerated osteoarthrosis (OA) progression.               Sixty-six male guinea pigs were randomly divided into 6 groups. During a 9-week...

  20. Differences in tibial subchondral bone structure evaluated using plain radiographs between knees with and without cartilage damage or bone marrow lesions. The Oulu knee osteoarthritis study

    International Nuclear Information System (INIS)

    Hirvasniemi, Jukka; Thevenot, Jerome; Podlipska, Jana; Guermazi, Ali; Roemer, Frank W.; Nieminen, Miika T.; Saarakkala, Simo

    2017-01-01

    To investigate whether subchondral bone structure from plain radiographs is different between subjects with and without articular cartilage damage or bone marrow lesions (BMLs). Radiography-based bone structure was assessed from 80 subjects with different stages of knee osteoarthritis using entropy of Laplacian-based image (E Lap ) and local binary patterns (E LBP ), homogeneity index of local angles (HI Angles,mean ), and horizontal (FD Hor ) and vertical fractal dimensions (FD Ver ). Medial tibial articular cartilage damage and BMLs were scored using the magnetic resonance imaging osteoarthritis knee score. Level of statistical significance was set to p < 0.05. Subjects with medial tibial cartilage damage had significantly higher FD Ver and E LBP as well as lower E Lap and HI Angles,mean in the medial tibial subchondral bone region than subjects without damage. FD Hor , FD Ver , and E LBP were significantly higher, whereas E Lap and HI Angles,mean were lower in the medial trabecular bone region. Subjects with medial tibial BMLs had significantly higher FD Ver and E LBP as well as lower E Lap and HI Angles,mean in medial tibial subchondral bone. FD Hor , FD Ver , and E LBP were higher, whereas E Lap and HI Angles,mean were lower in medial trabecular bone. Our results support the use of bone structural analysis from radiographs when examining subjects with osteoarthritis or at risk of having it. (orig.)

  1. Sequential change in T2* values of cartilage, meniscus, and subchondral bone marrow in a rat model of knee osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Ping-Huei Tsai

    Full Text Available BACKGROUND: There is an emerging interest in using magnetic resonance imaging (MRI T2* measurement for the evaluation of degenerative cartilage in osteoarthritis (OA. However, relatively few studies have addressed OA-related changes in adjacent knee structures. This study used MRI T2* measurement to investigate sequential changes in knee cartilage, meniscus, and subchondral bone marrow in a rat OA model induced by anterior cruciate ligament transection (ACLX. MATERIALS AND METHODS: Eighteen male Sprague Dawley rats were randomly separated into three groups (n = 6 each group. Group 1 was the normal control group. Groups 2 and 3 received ACLX and sham-ACLX, respectively, of the right knee. T2* values were measured in the knee cartilage, the meniscus, and femoral subchondral bone marrow of all rats at 0, 4, 13, and 18 weeks after surgery. RESULTS: Cartilage T2* values were significantly higher at 4, 13, and 18 weeks postoperatively in rats of the ACLX group than in rats of the control and sham groups (p<0.001. In the ACLX group (compared to the sham and control groups, T2* values increased significantly first in the posterior horn of the medial meniscus at 4 weeks (p = 0.001, then in the anterior horn of the medial meniscus at 13 weeks (p<0.001, and began to increase significantly in the femoral subchondral bone marrow at 13 weeks (p = 0.043. CONCLUSION: Quantitative MR T2* measurements of OA-related tissues are feasible. Sequential change in T2* over time in cartilage, meniscus, and subchondral bone marrow were documented. This information could be potentially useful for in vivo monitoring of disease progression.

  2. Bone Cysts After Osteochondral Allograft Repair of Cartilage Defects in Goats Suggest Abnormal Interaction Between Subchondral Bone and Overlying Synovial Joint Tissues

    Science.gov (United States)

    Pallante-Kichura, Andrea L.; Cory, Esther; Bugbee, William D.; Sah, Robert L.

    2013-01-01

    The efficacy of osteochondral allografts (OCA) may be affected by osseous support of the articular cartilage, and thus affected by bone healing and remodeling in the OCA and surrounding host. Bone cysts, and their communication pathways, may be present in various locations after OCA insertion and reflect distinct pathogenic mechanisms. Previously, we analyzed the effect of OCA storage (FRESH, 4°C/14d, 4°C/28d, FROZEN) on cartilage quality in fifteen adult goats after 12 months in vivo. The objectives of this study were to further analyze OCA and contralateral non-operated (Non-Op) CONTROLS from the medial femoral condyle to (1) determine the effect of OCA storage on local subchondral (ScB) and trabecular (TB) bone structure, (2) characterize the location and structure of bone cysts and channels, and (3) assess the relationship between cartilage and bone properties. (1) Overall bone structure after OCA was altered compared to Non-Op, with OCA samples displaying bone cysts, ScB channels, and ScB roughening. ScB BV/TV in FROZEN OCA was lower than Non-Op and other OCA. TB BV/TV in FRESH, 4°C/14d, and 4°C/28d OCA did not vary compared to Non-Op, but BS/TV was lower. (2) OCA contained “basal” cysts, localized to deeper regions, some “subchondral” cysts, localized near the bone-cartilage interface, and some ScB channels. TB surrounding basal cysts exhibited higher BV/TV than Non-Op. (3) Basal cysts occurred (a) in isolation, (b) with subchondral cysts and ScB channels, (c) with ScB channels, or (d) with subchondral cysts, ScB channels, and ScB erosion. Deterioration of cartilage gross morphology was strongly associated with abnormal μCT bone structure. Evidence of cartilage-bone communication following OCA repair may favor fluid intrusion as a mechanism for subchondral cyst formation, while bone resorption at the graft-host interface without affecting overall bone and cartilage structure may favor bony contusion mechanism for basal cyst formation. These

  3. Abnormal subchondral bone microstructure following steroid administration is involved in the early pathogenesis of steroid-induced osteonecrosis.

    Science.gov (United States)

    Wang, L; Zhang, L; Pan, H; Peng, S; Zhao, X; Lu, W W

    2016-01-01

    Loss of bone microstructure integrity is thought to be related to osteonecrosis. But the relationship between the time when bone microstructure integrity loss appears and the onset of osteonecrosis has not yet been determined. Our study demonstrated abnormal changes of subchondral bone microstructure involved in the early pathogenesis of osteonecrosis. Using a rabbit model, we investigated the changes of subchondral bone microstructure following steroid administration to identify the onset of abnormal bone microstructure development in steroid-induced osteonecrosis. Fifty-five adult female Japanese White rabbits (mean body weight 3.5 kg; mean age 24 months) were used and randomly divided among three time points (3, 7, and 14 days) consisting of 15 rabbits each, received a single intramuscular injection of methylprednisolone acetate (MP; Pfizer Manufacturing Belgium NV) at a dose of 4 mg/kg, and a control group consisting of 10 rabbits was fed and housed under identical conditions but were not given steroid injections. A micro-CT scanner was applied to detect changes in the trabecular region of subchondral bone of excised femoral head samples. Parameters including bone volume fraction (BV/TV), bone surface (BS), trabecular bone pattern factor (Tb.Pf), trabecular thickness/number/separation (Tb.Th, Tb.N, and Tb.Sp), and structure model index (SMI) were evaluated using the software CTAn (SkyScan). After micro-CT scans, bilateral femoral heads were cut in the coronal plane at a thickness of 4 μm. The sections were then stained with haematoxylin-eosin and used for the diagnosis of osteonecrosis and the rate of development of osteonecrosis. The BV/TV, BS, Tb.Th and Tb.N demonstrated a time-dependent decline from 3, 7, and 14 days compared with the control group, while the Tb.Pf, Tb.Sp and SMI demonstrated an increase at 3, 7, and 14 days compared with the control group. For the histopathology portion, osteonecrosis was not seen 3 days after steroid treatment, but was

  4. Age-dependent Changes in the Articular Cartilage and Subchondral Bone of C57BL/6 Mice after Surgical Destabilization of Medial Meniscus.

    Science.gov (United States)

    Huang, Henry; Skelly, Jordan D; Ayers, David C; Song, Jie

    2017-02-09

    Age is the primary risk factor for osteoarthritis (OA), yet surgical OA mouse models such as destabilization of the medial meniscus (DMM) used for evaluating disease-modifying OA targets are frequently performed on young adult mice only. This study investigates how age affects cartilage and subchondral bone changes in mouse joints following DMM. DMM was performed on male C57BL/6 mice at 4 months (4 M), 12 months (12 M) and 19+ months (19 M+) and on females at 12 M and 18 M+. Two months after surgery, operated and unoperated contralateral knees were harvested and evaluated using cartilage histology scores and μCT quantification of subchondral bone plate thickness and osteophyte formation. The 12 M and 19 M+ male mice developed more cartilage erosions and thicker subchondral bone plates after DMM than 4 M males. The size of osteophytes trended up with age, while the bone volume fraction was significantly higher in the 19 M+ group. Furthermore, 12 M females developed milder OA than males as indicated by less cartilage degradation, less subchondral bone plate sclerosis and smaller osteophytes. Our results reveal distinct age/gender-dependent structural changes in joint cartilage and subchondral bone post-DMM, facilitating more thoughtful selection of murine age/gender when using this surgical technique for translational OA research.

  5. Age-dependent Changes in the Articular Cartilage and Subchondral Bone of C57BL/6 Mice after Surgical Destabilization of Medial Meniscus

    Science.gov (United States)

    Huang, Henry; Skelly, Jordan D.; Ayers, David C.; Song, Jie

    2017-01-01

    Age is the primary risk factor for osteoarthritis (OA), yet surgical OA mouse models such as destabilization of the medial meniscus (DMM) used for evaluating disease-modifying OA targets are frequently performed on young adult mice only. This study investigates how age affects cartilage and subchondral bone changes in mouse joints following DMM. DMM was performed on male C57BL/6 mice at 4 months (4 M), 12 months (12 M) and 19+ months (19 M+) and on females at 12 M and 18 M+. Two months after surgery, operated and unoperated contralateral knees were harvested and evaluated using cartilage histology scores and μCT quantification of subchondral bone plate thickness and osteophyte formation. The 12 M and 19 M+ male mice developed more cartilage erosions and thicker subchondral bone plates after DMM than 4 M males. The size of osteophytes trended up with age, while the bone volume fraction was significantly higher in the 19 M+ group. Furthermore, 12 M females developed milder OA than males as indicated by less cartilage degradation, less subchondral bone plate sclerosis and smaller osteophytes. Our results reveal distinct age/gender-dependent structural changes in joint cartilage and subchondral bone post-DMM, facilitating more thoughtful selection of murine age/gender when using this surgical technique for translational OA research. PMID:28181577

  6. The role of subchondral bone remodeling in osteoarthritis: reduction of cartilage degeneration and prevention of osteophyte formation by alendronate in the rat anterior cruciate ligament transection model.

    Science.gov (United States)

    Hayami, Tadashi; Pickarski, Maureen; Wesolowski, Gregg A; McLane, Julia; Bone, Ashleigh; Destefano, James; Rodan, Gideon A; Duong, Le T

    2004-04-01

    It has been suggested that subchondral bone remodeling plays a role in the progression of osteoarthritis (OA). To test this hypothesis, we characterized the changes in the rat anterior cruciate ligament transection (ACLT) model of OA and evaluated the effects of alendronate (ALN), a potent inhibitor of bone resorption, on cartilage degradation and on osteophyte formation. Male Sprague-Dawley rats underwent ACLT or sham operation of the right knee. Animals were then treated with ALN (0.03 and 0.24 microg/kg/week subcutaneously) and necropsied at 2 or 10 weeks postsurgery. OA changes were evaluated. Subchondral bone volume and osteophyte area were measured by histomorphometric analysis. Coimmunostaining for transforming growth factor beta (TGF beta), matrix metalloproteinase 9 (MMP-9), and MMP-13 was performed to investigate the effect of ALN on local activation of TGF beta. ALN was chondroprotective at both dosages, as determined by histologic criteria and collagen degradation markers. ALN suppressed subchondral bone resorption, which was markedly increased 2 weeks postsurgery, and prevented the subsequent increase in bone formation 10 weeks postsurgery, in the untreated tibial plateau of ACLT joints. Furthermore, ALN reduced the incidence and area of osteophytes in a dose-dependent manner. ALN also inhibited vascular invasion into the calcified cartilage in rats with OA and blocked osteoclast recruitment to subchondral bone and osteophytes. ALN treatment reduced the local release of active TGF beta, possibly via inhibition of MMP-13 expression in articular cartilage and MMP-9 expression in subchondral bone. Subchondral bone remodeling plays an important role in the pathogenesis of OA. ALN or other inhibitors of bone resorption could potentially be used as disease-modifying agents in the treatment of OA.

  7. Comparative Analysis of Bone Structural Parameters Reveals Subchondral Cortical Plate Resorption and Increased Trabecular Bone Remodeling in Human Facet Joint Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Cordula Netzer

    2018-03-01

    Full Text Available Facet joint osteoarthritis is a prominent feature of degenerative spine disorders, highly prevalent in ageing populations, and considered a major cause for chronic lower back pain. Since there is no targeted pharmacological therapy, clinical management of disease includes analgesic or surgical treatment. The specific cellular, molecular, and structural changes underpinning facet joint osteoarthritis remain largely elusive. The aim of this study was to determine osteoarthritis-related structural alterations in cortical and trabecular subchondral bone compartments. To this end, we conducted comparative micro computed tomography analysis in healthy (n = 15 and osteoarthritic (n = 22 lumbar facet joints. In osteoarthritic joints, subchondral cortical plate thickness and porosity were significantly reduced. The trabecular compartment displayed a 42 percent increase in bone volume fraction due to an increase in trabecular number, but not trabecular thickness. Bone structural alterations were associated with radiological osteoarthritis severity, mildly age-dependent but not gender-dependent. There was a lack of association between structural parameters of cortical and trabecular compartments in healthy and osteoarthritic specimens. The specific structural alterations suggest elevated subchondral bone resorption and turnover as a potential treatment target in facet joint osteoarthritis.

  8. The role of calcified cartilage and subchondral bone in the initiation and progression of ochronotic arthropathy in alkaptonuria.

    Science.gov (United States)

    Taylor, A M; Boyde, A; Wilson, P J M; Jarvis, J C; Davidson, J S; Hunt, J A; Ranganath, L R; Gallagher, J A

    2011-12-01

    Alkaptonuria is a genetic disorder of tyrosine metabolism, resulting in elevated circulating concentrations of homogentisic acid. Homogentisic acid is deposited as a polymer, termed ochronotic pigment, in collagenous tissues, especially cartilages of weight-bearing joints, leading to a severe osteoarthropathy. We undertook this study to investigate the initiation and progression of ochronosis from the earliest detection of pigment through complete joint failure. Nine joint samples with varying severities of ochronosis were obtained from alkaptonuria patients undergoing surgery and compared to joint samples obtained from osteoarthritis (OA) patients. Samples were analyzed by light and fluorescence microscopy, 3-dimensional scanning electron microscopy (SEM), and the quantitative backscattered electron mode of SEM. Cartilage samples were mechanically tested by compression to determine Young's modulus of pigmented, nonpigmented, and OA cartilage samples. In alkaptonuria samples with the least advanced ochronosis, pigment was observed intracellularly and in the territorial matrix of individual chondrocytes at the boundary of the subchondral bone and calcified cartilage. In more advanced ochronosis, pigmentation was widespread throughout the hyaline cartilage in either granular composition or as blanket pigmentation in which there is complete and homogenous pigmentation of cartilage matrix. Once hyaline cartilage was extensively pigmented, there was aggressive osteoclastic resorption of the subchondral plate. Pigmented cartilage became impacted on less highly mineralized trabeculae and embedded in the marrow space. Pigmented cartilage samples were much stiffer than nonpigmented or OA cartilage as revealed by a significant difference in Young's modulus. Using alkaptonuria cartilage specimens with a wide spectrum of pigmentation, we have characterized the progression of ochronosis. Intact cartilage appears to be resistant to pigmentation but becomes susceptible following

  9. Dual-energy X-ray absorptiometry applied to the assessment of tibial subchondral bone mineral density in osteoarthritis of the knee

    International Nuclear Information System (INIS)

    Clarke, S.; Duddy, J.; Nickols, G.; Kirwan, J.R.; Wakeley, C.; Watt, I.; Ellingham, K.; Sharif, M.; Elson, C.J.

    2004-01-01

    Plain X-ray is an imprecise tool for monitoring the subchondral bony changes associated with the development of knee osteoarthritis (OA). Our objective was to develop and validate a technique for assessing tibial subchondral bone density (BMD) in knee OA using dual energy X-ray absorptiometry (DXA). Patients with OA of at least one knee underwent DXA scanning of both knees. Regions of interest (ROI) were placed in the lateral and medial compartments of tibial subchondral bone. Weight-bearing plain X-rays and Te 99m scintiscans of both knees were obtained and scored. One hundred and twelve patients (223 knees) underwent DXA and radiography. Intra-observer CV% was 2.4% and 1.0% for the medial and lateral ROI respectively. Definite OA (Kellgren and Lawrence Grade 2, 3 or 4) was correlated with age-related preservation of subchondral BMD compared to radiographically normal knees. Raised BMD was also associated with subchondral sclerosis, and positive scintigraphy. DXA may provide a safe, rapid and reliable means of assessing knee OA. Cross-sectional age-related subchondral tibial BMD loss is attenuated by knee OA. (orig.)

  10. Differences in tibial subchondral bone structure evaluated using plain radiographs between knees with and without cartilage damage or bone marrow lesions. The Oulu knee osteoarthritis study

    Energy Technology Data Exchange (ETDEWEB)

    Hirvasniemi, Jukka [University of Oulu, Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, Oulu (Finland); Oulu University Hospital and University of Oulu, Medical Research Center Oulu, Oulu (Finland); Thevenot, Jerome; Podlipska, Jana [University of Oulu, Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, Oulu (Finland); University of Oulu, Infotech Oulu, Oulu (Finland); Guermazi, Ali [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Roemer, Frank W. [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Nieminen, Miika T.; Saarakkala, Simo [University of Oulu, Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, Oulu (Finland); Oulu University Hospital and University of Oulu, Medical Research Center Oulu, Oulu (Finland); University of Oulu, Infotech Oulu, Oulu (Finland); Oulu University Hospital, Department of Diagnostic Radiology, Oulu (Finland)

    2017-11-15

    To investigate whether subchondral bone structure from plain radiographs is different between subjects with and without articular cartilage damage or bone marrow lesions (BMLs). Radiography-based bone structure was assessed from 80 subjects with different stages of knee osteoarthritis using entropy of Laplacian-based image (E{sub Lap}) and local binary patterns (E{sub LBP}), homogeneity index of local angles (HI{sub Angles,mean}), and horizontal (FD{sub Hor}) and vertical fractal dimensions (FD{sub Ver}). Medial tibial articular cartilage damage and BMLs were scored using the magnetic resonance imaging osteoarthritis knee score. Level of statistical significance was set to p < 0.05. Subjects with medial tibial cartilage damage had significantly higher FD{sub Ver} and E{sub LBP} as well as lower E{sub Lap} and HI{sub Angles,mean} in the medial tibial subchondral bone region than subjects without damage. FD{sub Hor}, FD{sub Ver}, and E{sub LBP} were significantly higher, whereas E{sub Lap} and HI{sub Angles,mean} were lower in the medial trabecular bone region. Subjects with medial tibial BMLs had significantly higher FD{sub Ver} and E{sub LBP} as well as lower E{sub Lap} and HI{sub Angles,mean} in medial tibial subchondral bone. FD{sub Hor}, FD{sub Ver}, and E{sub LBP} were higher, whereas E{sub Lap} and HI{sub Angles,mean} were lower in medial trabecular bone. Our results support the use of bone structural analysis from radiographs when examining subjects with osteoarthritis or at risk of having it. (orig.)

  11. Inhibition of SDF-1α/CXCR4 Signalling in Subchondral Bone Attenuates Post-Traumatic Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Yonghui Dong

    2016-06-01

    Full Text Available Previous studies showed that SDF-1α is a catabolic factor that can infiltrate cartilage, decrease proteoglycan content, and increase MMP-13 activity. Inhibiting the SDF-1α/CXCR4 signalling pathway can attenuate the pathogenesis of osteoarthritis (OA. Recent studies have also shown that SDF-1α enhances chondrocyte proliferation and maturation. These results appear to be contradictory. In the current study, we used a destabilisation OA animal model to investigate the effects of SDF-1α/CXCR4 signalling in the tibial subchondral bone and the OA pathological process. Post-traumatic osteoarthritis (PTOA mice models were prepared by transecting the anterior cruciate ligament (ACLT, or a sham surgery was performed, in a total of 30 mice. Mice were treated with phosphate buffer saline (PBS or AMD3100 (an inhibitor of CXCR4 and sacrificed at 30 days post ACLT or sham surgery. Tibial subchondral bone status was quantified by micro-computed tomography (μCT. Knee-joint histology was analysed to examine the articular cartilage and joint degeneration. The levels of SDF-1α and collagen type I c-telopeptidefragments (CTX-I were quantified by ELISA. Bone marrow mononuclear cells (BMMCs were used to clarify the effects of SDF-1α on osteoclast formation and activity in vivo. μCT analysis revealed significant loss of trabecular bone from tibial subchondral bone post-ACLT, which was effectively prevented by AMD3100. AMD3100 could partially prevent bone loss and articular cartilage degeneration. Serum biomarkers revealed an increase in SDF-1α and bone resorption, which were also reduced by AMD3100. SDF-1α can promote osteoclast formation and the expression oftartrate resistant acid phosphatase (TRAP, cathepsin K (CK, and matrix metalloproteinase (MMP-9 in osteoclasts by activating the MAPK pathway, including ERK and p38, but not JNK. In conclusion, inhibition of SDF-1α/CXCR4signalling was able to prevent trabecular bone loss and attenuated cartilage

  12. Asporin and transforming growth factor-beta gene expression in osteoblasts from subchondral bone and osteophytes in osteoarthritis.

    Science.gov (United States)

    Sakao, Kei; Takahashi, Kenji A; Arai, Yuji; Saito, Masazumi; Honjyo, Kuniaki; Hiraoka, Nobuyuki; Kishida, Tsunao; Mazda, Osam; Imanishi, Jiro; Kubo, Toshikazu

    2009-11-01

    To clarify the significance of subchondral bone and osteophytes in the pathology of osteoarthritis (OA), we investigated the expression of asporin (ASPN), transforming growth factor-beta1 (TGF-beta1), TGF-beta2, TGF-beta3, and runt-related transcription factor-2 (Runx2) genes involved in bone metabolism. Osteoblasts were isolated from 19 patients diagnosed with knee OA and from 4 patients diagnosed with femoral neck fracture. Osteoblast expression of mRNA encoding ASPN, TGF-beta1, TGF-beta2, TGF-beta3, and Runx2 was analyzed using real-time RT-PCR. Expression of ASPN, TGF-beta1, and TGF-beta3 mRNA in the subchondral bone and osteophytes of OA patients increased compared with that of non-OA patients. The ratio of ASPN to TGF-beta1 mRNA in patients with severe cartilage damage was higher than that in patients with mild cartilage damage. The increased ratio of ASPN mRNA to TGF-beta1 mRNA in patients with severe relative to mild cartilage damage indicates that increased ASPN mRNA expression was significantly associated with the severity of cartilage degeneration. This finding suggests that ASPN may regulate TGF-beta1-mediated factors in the development of OA, which may provide clues as to the underlying pathology of OA.

  13. Identifying compositional and structural changes in spongy and subchondral bone from the hip joints of patients with osteoarthritis using Raman spectroscopy

    Science.gov (United States)

    Buchwald, Tomasz; Niciejewski, Krzysztof; Kozielski, Marek; Szybowicz, Mirosław; Siatkowski, Marcin; Krauss, Hanna

    2012-01-01

    Raman microspectroscopy was used to examine the biochemical composition and molecular structure of extracellular matrix in spongy and subchondral bone collected from patients with clinical and radiological evidence of idiopathic osteoarthritis of the hip and from patients who underwent a femoral neck fracture, as a result of trauma, without previous clinical and radiological evidence of osteoarthritis. The objectives of the study were to determine the levels of mineralization, carbonate accumulation and collagen quality in bone tissue. The subchondral bone from osteoarthritis patients in comparison with control subject is less mineralized due to a decrease in the hydroxyapatite concentration. However, the extent of carbonate accumulation in the apatite crystal lattice increases, most likely due to deficient mineralization. The alpha helix to random coil band area ratio reveals that collagen matrix in subchondral bone is more ordered in osteoarthritis disease. The hydroxyapatite to collagen, carbonate apatite to hydroxyapatite and alpha helix to random coil band area ratios are not significantly changed in the differently loaded sites of femoral head. The significant differences also are not visible in mineral and organic constituents' content in spongy bone beneath the subchondral bone in osteoarthritis disease.

  14. Can high-resolution peripheral quantitative computed tomography imaging of subchondral and cortical bone predict condylar fracture in Thoroughbred racehorses?

    Science.gov (United States)

    Trope, G D; Ghasem-Zadeh, A; Anderson, G A; Mackie, E J; Whitton, R C

    2015-07-01

    High-resolution 3D imaging may improve the prediction and/or early identification of condylar fractures of the distal metacarpus/tarsus and reduce the frequency of breakdown injury in racehorses. To test the hypotheses that horses suffering condylar fractures have higher bone volume fraction (BV/TV) of the distal metacarpal epiphysis, greater subchondral bone thickness at the fracture site and higher second moment of inertia in the metacarpal midshaft as identified with high-resolution 3D imaging. Cross-sectional study using cadaver material. Thoroughbreds that died on racetracks were grouped as: 1) horses with third metacarpal (McIII) fractures with a condylar component (cases, n = 13); 2) horses with no limb fracture (controls, n = 8); 3) horses with fractures in other bones or suspensory apparatus disruption (other fatal injuries, n = 16). The palmar condyles of McIII and the midshaft were examined with high resolution peripheral quantitative computed tomography (HR-pQCT). Statistical analysis included logistic regression and Spearman's correlation. There were no significant differences in BV/TV of distal McIII and second moment of inertia of the midshaft between cases and controls. Epiphyseal bone BV/TV was greater in injured limbs of horses with any fatal limb injury (Groups 1 and 3 combined) compared with controls (odds ratio = 1.20, 95% confidence interval 1.01-1.42, P = 0.034). An epiphyseal BV/TV>0.742 resulted in a sensitivity of 82.8% and specificity of 62.5% in identifying horses with fatal limb injury. In horses without condylar fracture, increased subchondral bone thickness was associated with palmar osteochondral disease lesions in the adjacent condyle (rs = 0.65, Phorses at risk of any fatal breakdown injury but not metacarpal condylar fractures. Measurement of parasagittal groove subchondral bone thickness is complicated by adjacent palmar osteochondral disease lesions. Thus, high-resolution imaging of the distal metacarpus appears to have limited

  15. The role of inhibition by phosphocitrate and its analogue in chondrocyte differentiation and subchondral bone advance in Hartley guinea pigs.

    Science.gov (United States)

    Sun, Yubo; Kiraly, Alex J; Cox, Michael; Mauerhan, David R; Hanley, Edward N

    2018-04-01

    Phosphocitrate (PC) and its analogue, PC-β ethyl ester, inhibit articular cartilage degeneration in Hartley guinea pigs. However, the underlying molecular mechanisms remain unclear. The present study aimed to investigate the hypothesis that PC exerted its disease-modifying effect on osteoarthritis (OA), in part, by inhibiting a molecular program similar to that in the endochondral pathway of ossification. The results demonstrated that severe proteoglycan loss occurred in the superficial and middle zones, as well as in the calcified zone of articular cartilage in the Hartley guinea pigs. Subchondral bone advance was greater in the control Hartley guinea pigs compared with PC- or PC analogue-treated guinea pigs. Resorption of cartilage bars or islands and vascular invasion in the growth plate were also greater in the control guinea pigs compared with the PC- or PC analogue-treated guinea pigs. The levels of matrix metalloproteinase-13 and type X collagen within the articular cartilage and growth plate were significantly increased in the control guinea pigs compared with PC-treated guinea pigs (Pguinea pigs exhibited a hypertrophic phenotype and recapitulated a developmental molecular program similar to the endochondral pathway of ossification. Activation of this molecular program resulted in resorption of calcified articular cartilage and subchondral bone advance. This suggests that PC and PC analogues exerted their OA disease-modifying activity, in part, by inhibiting this molecular program.

  16. Annulus Fibrosus Can Strip Hyaline Cartilage End Plate from Subchondral Bone: A Study of the Intervertebral Disk in Tension.

    Science.gov (United States)

    Balkovec, Christian; Adams, Michael A; Dolan, Patricia; McGill, Stuart M

    2015-10-01

    Study Design Biomechanical study on cadaveric spines. Objective Spinal bending causes the annulus to pull vertically (axially) on the end plate, but failure mechanisms in response to this type of loading are poorly understood. Therefore, the objective of this study was to identify the weak point of the intervertebral disk in tension. Methods Cadaveric motion segments (aged 79 to 88 years) were dissected to create midsagittal blocks of tissue, with ∼10 mm of bone superior and inferior to the disk. From these blocks, 14 bone-disk-bone slices (average 4.8 mm thick) were cut in the frontal plane. Each slice was gripped by its bony ends and stretched to failure at 1 mm/s. Mode of failure was recorded using a digital camera. Results Of the 14 slices, 10 failed by the hyaline cartilage being peeled off the subchondral bone, with the failure starting opposite the lateral annulus and proceeding medially. Two slices failed by rupturing of the trabecular bone, and a further two failed in the annulus. Conclusions The hyaline cartilage-bone junction is the disk's weak link in tension. These findings provide a plausible mechanism for the appearance of bone and cartilage fragments in herniated material. Stripping cartilage from the bony end plate would result in the herniated mass containing relatively stiff cartilage that does not easily resorb.

  17. The normal human chondro-osseous junctional region: evidence for contact of uncalcified cartilage with subchondral bone and marrow spaces

    Directory of Open Access Journals (Sweden)

    Stoddart Robert W

    2006-06-01

    Full Text Available Abstract Background The chondro-osseous junctional region of diarthrodial joints is peculiarly complex and may be considered to consist of the deepest layer of non-calcified cartilage, the tidemark, the layer of calcified cartilage, a thin cement line (between the calcified cartilage and the subchondral bone and the subchondral bone. A detailed knowledge of the structure, function and pathophysiology of the normal chondro-osseous junction is essential for an understanding of the pathogenesis of osteoarthrosis. Methods Full thickness samples from human knee joints were processed and embedded in paraffin wax. One hundred serial sections (10 μm thick were taken from the chondro-osseous junctional region of a block from the medial tibial plateau of a normal joint. They were stained with haematoxylin and eosin and photographed. For a simple physical reconstruction images of each 10th sequential tissue section were printed and the areas of the photomicrographs containing the chondro-osseous junctional region were cut out and then overlaid so as to create a three-dimensional (3D model of this region. A 3D reconstruction was also made using computer modelling. Results Histochemical staining revealed some instances where prolongations of uncalcified cartilage, delineated by the tidemark, dipped into the calcified cartilage and, in places, abutted onto subchondral bone and marrow spaces. Small areas of uncalcified cartilage containing chondrocytes (virtual islands were seen, in two-dimensional (2D sections, to be apparently entombed in calcified matrix. The simple physical 3D reconstruction confirmed that these prolongations of uncalcified cartilage were continuous with the cartilage of zone IV and demonstrated that the virtual islands of uncalcified cartilage were cross-sections of these prolongations. The computer-generated 3D reconstructions clearly demonstrated that the uncalcified prolongations ran through the calcified cartilage to touch bone and

  18. A comparison of conventional maximum intensity projection with a new depth-specific topographic mapping technique in the CT analysis of proximal tibial subchondral bone density

    International Nuclear Information System (INIS)

    Johnston, James D.; Kontulainen, Saija A.; Masri, Bassam A.; Wilson, David R.

    2010-01-01

    The objective was to identify subchondral bone density differences between normal and osteoarthritic (OA) proximal tibiae using computed tomography osteoabsorptiometry (CT-OAM) and computed tomography topographic mapping of subchondral density (CT-TOMASD). Sixteen intact cadaver knees from ten donors (8 male:2 female; mean age:77.8, SD:7.4 years) were categorized as normal (n = 10) or OA (n = 6) based upon CT reconstructions. CT-OAM assessed maximum subchondral bone mineral density (BMD). CT-TOMASD assessed average subchondral BMD across three layers (0-2.5, 2.5-5 and 5-10 mm) measured in relation to depth from the subchondral surface. Regional analyses of CT-OAM and CT-TOMASD included: medial BMD, lateral BMD, and average BMD of a 10-mm diameter area that searched each medial and lateral plateau for the highest ''focal'' density present within each knee. Compared with normal knees, both CT-OAM and CT-TOMASD demonstrated an average of 17% greater whole medial compartment density in OA knees (p 0.05). CT-TOMASD focal region analyses revealed an average of 24% greater density in the 0- to 2.5-mm layer (p = 0.003) and 36% greater density in the 2.5- to 5-mm layer (p = 0.034) in OA knees. Both CT-OAM and TOMASD identified higher medial compartment density in OA tibiae compared with normal tibiae. In addition, CT-TOMASD indicated greater focal density differences between normal and OA knees with increased depth from the subchondral surface. Depth-specific density analyses may help identify and quantify small changes in subchondral BMD associated with OA disease onset and progression. (orig.)

  19. Alpha C-telopeptide of type I collagen is associated with subchondral bone turnover and predicts progression of joint space narrowing and osteophytes in osteoarthritis.

    Science.gov (United States)

    Huebner, Janet L; Bay-Jensen, Anne C; Huffman, Kim M; He, Yi; Leeming, Diana J; McDaniel, Gary E; Karsdal, Morten A; Kraus, Virginia B

    2014-09-01

    To evaluate joint tissue remodeling using the urinary collagen biomarkers urinary α-C-telopeptide of type I collagen (α-CTX) and urinary C-telopeptide of type II collagen (CTX-II) and to determine the association of these biomarkers with osteoarthritis (OA) severity, progression, and localized knee bone turnover. Participants (n = 149) with symptomatic and radiographic knee OA underwent fixed-flexion knee radiography at baseline and 3 years, and late-phase bone scintigraphy of both knees at baseline, which were scored semiquantitatively for osteophyte and joint space narrowing (JSN) severity and uptake intensity, with scores summed across knees. Urinary concentrations of α-CTX and CTX-II were determined by enzyme-linked immunosorbent assay. Immunohistochemical analysis of human OA knees was performed to localize the joint tissue origin of the biomarker epitopes. Urinary α-CTX concentrations correlated strongly with the intensity of bone scintigraphic uptake and with JSN progression (risk ratio 13.2) and osteophyte progression (risk ratio 3). Urinary CTX-II concentrations were strongly associated with intensity of bone scintigraphic uptake, with JSN and osteophyte severity, and with OA progression based on osteophyte score. Urinary α-CTX localized primarily to high bone turnover areas in subchondral bone. CTX-II localized to the bone-cartilage interface, the tidemark, and damaged articular cartilage. Baseline urinary α-CTX, which was localized to high turnover areas of subchondral bone, was associated with dynamic bone turnover of knees, as signified by scintigraphy, and progression of both osteophytes and JSN. Urinary CTX-II correlated with JSN and osteophyte severity and progression of osteophytes. To our knowledge, this represents the first report of serologic markers reflecting subchondral bone turnover. These collagen markers may be useful for noninvasive detection and quantification of active subchondral bone turnover and joint remodeling in knee OA

  20. The inhibition of subchondral bone lesions significantly reversed the weight-bearing deficit and the overexpression of CGRP in DRG neurons, GFAP and Iba-1 in the spinal dorsal horn in the monosodium iodoacetate induced model of osteoarthritis pain.

    Directory of Open Access Journals (Sweden)

    Degang Yu

    Full Text Available Chronic pain is the most prominent and disabling symptom of osteoarthritis (OA. Clinical data suggest that subchondral bone lesions contribute to the occurrence of joint pain. The present study investigated the effect of the inhibition of subchondral bone lesions on joint pain.Osteoarthritic pain was induced by an injection of monosodium iodoacetate (MIA into the rat knee joint. Zoledronic acid (ZOL, a third generation of bisphosphonate, was used to inhibit subchondral bone lesions. Joint histomorphology was evaluated using X-ray micro computed tomography scanning and hematoxylin-eosin staining. The activity of osteoclast in subchondral bone was evaluated using tartrate-resistant acid phosphatase staining. Joint pain was evaluated using weight-bearing asymmetry, the expression of calcitonin gene-related peptide (CGRP in the dorsal root ganglion (DRG, and spinal glial activation status using glial fibrillary acidic protein (GFAP and ionized calcium binding adaptor molecule-1 (Iba-1 immunofluorescence. Afferent neurons in the DRGs that innervated the joints were identified using retrograde fluorogold labeling.MIA injections induced significant histomorphological alterations and joint pain. The inhibition of subchondral bone lesions by ZOL significantly reduced the MIA-induced weight-bearing deficit and overexpression of CGRP in DRG neurons, GFAP and Iba-1 in the spinal dorsal horn at 3 and 6 weeks after MIA injection; however, joint swelling and synovial reaction were unaffected.The inhibition of subchondral bone lesions alleviated joint pain. Subchondral bone lesions should be a key target in the management of osteoarthritic joint pain.

  1. Treadmill Running Ameliorates Destruction of Articular Cartilage and Subchondral Bone, Not Only Synovitis, in a Rheumatoid Arthritis Rat Model

    Directory of Open Access Journals (Sweden)

    Seiji Shimomura

    2018-06-01

    Full Text Available We analyzed the influence of treadmill running on rheumatoid arthritis (RA joints using a collagen-induced arthritis (CIA rat model. Eight-week-old male Dark Agouti rats were randomly divided into four groups: The control group, treadmill group (30 min/day for 4 weeks from 10-weeks-old, CIA group (induced CIA at 8-weeks-old, and CIA + treadmill group. Destruction of the ankle joint was evaluated by histological analyses. Morphological changes of subchondral bone were analyzed by μ-CT. CIA treatment-induced synovial membrane invasion, articular cartilage destruction, and bone erosion. Treadmill running improved these changes. The synovial membrane in CIA rats produced a large amount of tumor necrosis factor-α and Connexin 43; production was significantly suppressed by treadmill running. On μ-CT of the talus, bone volume fraction (BV/TV was significantly decreased in the CIA group. Marrow star volume (MSV, an index of bone loss, was significantly increased. These changes were significantly improved by treadmill running. Bone destruction in the talus was significantly increased with CIA and was suppressed by treadmill running. On tartrate-resistant acid phosphate and alkaline phosphatase (TRAP/ALP staining, the number of osteoclasts around the pannus was decreased by treadmill running. These findings indicate that treadmill running in CIA rats inhibited synovial hyperplasia and joint destruction.

  2. Subchondral chitosan/blood implant-guided bone plate resorption and woven bone repair is coupled to hyaline cartilage regeneration from microdrill holes in aged rabbit knees.

    Science.gov (United States)

    Guzmán-Morales, J; Lafantaisie-Favreau, C-H; Chen, G; Hoemann, C D

    2014-02-01

    Little is known of how to routinely elicit hyaline cartilage repair tissue in middle-aged patients. We tested the hypothesis that in skeletally aged rabbit knees, microdrill holes can be stimulated to remodel the bone plate and induce a more integrated, voluminous and hyaline cartilage repair tissue when treated by subchondral chitosan/blood implants. New Zealand White rabbits (13 or 32 months old, N = 7) received two 1.5 mm diameter, 2 mm depth drill holes in each knee, either left to bleed as surgical controls or press-fit with a 10 kDa (distal hole: 10K) or 40 kDa (proximal hole: 40K) chitosan/blood implant with fluorescent chitosan tracer. Post-operative knee effusion was documented. Repair tissues at day 0 (N = 1) and day 70 post-surgery (N = 6) were analyzed by micro-computed tomography, and by histological scoring and histomorphometry (SafO, Col-2, and Col-1) at day 70. All chitosan implants were completely cleared after 70 days, without increasing transient post-operative knee effusion compared to controls. Proximal control holes had worse osteochondral repair than distal holes. Both implant formulations induced bone remodeling and improved lateral integration of the bone plate at the hole edge. The 40K implant inhibited further bone repair inside 50% of the proximal holes, while the 10K implant specifically induced a "wound bloom" reaction, characterized by decreased bone plate density in a limited zone beyond the initial hole edge, and increased woven bone (WB) plate repair inside the initial hole (P = 0.016), which was accompanied by a more voluminous and hyaline cartilage repair (P holes with a biodegradable subchondral implant that elicits bone plate resorption followed by anabolic WB repair within a 70-day repair period. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  3. Quantitative histological grading methods to assess subchondral bone and synovium changes subsequent to medial meniscus transection in the rat.

    Science.gov (United States)

    Kloefkorn, Heidi E; Allen, Kyle D

    The importance of the medial meniscus to knee health is demonstrated by studies which show meniscus injuries significantly increase the likelihood of developing osteoarthritis (OA), and knee OA can be modeled in rodents using simulated meniscus injuries. Traditionally, histological assessments of OA in these models have focused on damage to the articular cartilage; however, OA is now viewed as a disease of the entire joint as an organ system. The aim of this study was to develop quantitative histological measures of bone and synovial changes in a rat medial meniscus injury model of knee OA. To initiate OA, a medial meniscus transection (MMT) and a medial collateral ligament transection (MCLT) were performed in 32 male Lewis rats (MMT group). MCLT alone served as the sham procedure in 32 additional rats (MCLT sham group). At weeks 1, 2, 4, and 6 post-surgery, histological assessment of subchondral bone and synovium was performed (n = 8 per group per time point). Trabecular bone area and the ossification width at the osteochondral interface increased in both the MMT and MCLT groups. Subintimal synovial cell morphology also changed in MMT and MCLT groups relative to naïve animals. OA affects the joint as an organ system, and quantifying changes throughout an entire joint can improve our understanding of the relationship between joint destruction and painful OA symptoms following meniscus injury.

  4. Effect of open wedge high tibial osteotomy on the lateral tibiofemoral compartment in sheep. Part III: analysis of the microstructure of the subchondral bone and correlations with the articular cartilage and meniscus.

    Science.gov (United States)

    Ziegler, Raphaela; Goebel, Lars; Seidel, Roland; Cucchiarini, Magali; Pape, Dietrich; Madry, Henning

    2015-09-01

    First, to evaluate whether medial open wedge high tibial osteotomy (HTO) induces alterations of the microstructure of the lateral tibial subchondral bone plate of sheep. Second, to test the hypothesis that specific correlations exist between topographical structural alterations of the subchondral bone, the cartilage and the lateral meniscus. Three experimental groups received biplanar osteotomies of the right proximal tibiae: (a) closing wedge HTO (4.5° of tibial varus), (b) opening wedge HTO (4.5° tibial valgus; standard correction) and (c) opening wedge HTO (9.5° of valgus; overcorrection), each of which was compared to the non-osteotomised contralateral proximal tibiae. After 6 months, subchondral bone structure indices were measured by computed tomography. Correlations between the subchondral bone, the articular cartilage and the lateral meniscus were determined. Increased loading by valgus overcorrection led to an enlarged specific bone surface (BS/BV) in the subarticular spongiosa compared with unloading by varisation. The subchondral bone plate was 3.9-fold thicker in the central region of the lateral tibial plateau than in the submeniscal periphery. Its thickness in the central region significantly correlated with the thickness of the articular cartilage. In the submeniscal region, such correlation did not exist. In general, a higher degree of osteoarthritis (OA) correlated with alterations of the subchondral bone plate microstructure. OA of the submeniscal articular cartilage also correlated with worse matrix staining of the lateral meniscus. Osteoarthritis changes are associated with alterations of the subchondral bone plate microstructure. Specific topographical relationships exist in the central region between the articular cartilage and subchondral bone plate thickness, and in the submeniscal periphery between and the articular cartilage and lateral meniscus. From a clinical perspective, the combined follow-up data from this and the previous two

  5. Effect of exercise on thicknesses of mature hyaline cartilage, calcified cartilage, and subchondral bone of equine tarsi.

    Science.gov (United States)

    Tranquille, Carolyne A; Blunden, Antony S; Dyson, Sue J; Parkin, Tim D H; Goodship, Allen E; Murray, Rachel C

    2009-12-01

    OBJECTIVE-To investigate effects of exercise on hyaline cartilage (HC), calcified cartilage (CC), and subchondral bone (SCB) thickness patterns of equine tarsi. SAMPLE POPULATION-30 tarsi from cadavers of horses with known exercise history. PROCEDURES-Tarsi were assigned to 3 groups according to known exercise history as follows: pasture exercise only (PE tarsi), low-intensity general-purpose riding exercise (LE tarsi), and high-intensity elite competition riding exercise (EE tarsi). Osteochondral tissue from distal tarsal joints underwent histologic preparation. Hyaline cartilage, CC, and SCB thickness were measured at standard sites at medial, midline, and lateral locations across joints with a histomorphometric technique. RESULTS-HC, CC, and SCB thickness were significantly greater at all sites in EE tarsi, compared with PE tarsi; this was also true when LE tarsi were compared with PE tarsi. At specific sites, HC, CC, and SCB were significantly thicker in EE tarsi, compared with LE tarsi. Along the articular surface of the proximal aspect of the third metatarsal bone, SCB was thickest in EE tarsi and thinnest in LE tarsi; increases were greatest at sites previously reported to undergo peak strains and osteochondral damage. CONCLUSIONS AND CLINICAL RELEVANCE-Increased exercise was associated with increased HC, CC, and SCB thickness in mature horses. At sites that undergo high compressive strains, with a reported predisposition to osteoarthritic change, there was increased CC and SCB thickness. These results may provide insight into the interaction between adaptive response to exercise and pathological change.

  6. Presence of subchondral bone marrow edema at the time of treatment represents a negative prognostic factor for early outcome after autologous chondrocyte implantation

    DEFF Research Database (Denmark)

    Niemeyer, Philipp; Salzmann, Gian; Steinwachs, Matthias

    2010-01-01

    INTRODUCTION: Since introduction of autologous chondrocyte implantation (ACI), various factors have been described that influence the clinical outcome. The present paper investigates the influence of bone marrow edema at time of treatment on clinical function before and in the early clinical course...... after ACI. METHODS: 67 patients treated with ACI for cartilage defects of the knee joint were included. Presence of subchondral bone marrow edema was graded as absent (1), mild (2), moderate (3) or severe (4) using magnetic resonance (MR) imaging before surgery. All patients were assessed in terms...... of clinical function before surgery and 6 as well as 12 months after ACI using IKDC and Lysholm scores. Presence of subchondral edema was correlated with functional outcome. RESULTS: In 18 patients edema on initial MRI was graded as "absent", while 17 patients had grade 2 edema, 19 patients had grade 3 edema...

  7. Decreased bone tissue mineralization can partly explain subchondral sclerosis observed in osteoarthritis

    NARCIS (Netherlands)

    Cox, L.G.E.; Donkelaar, van C.C.; Rietbergen, van B.; Emans, P.J.; Ito, K.

    2012-01-01

    For many years, pharmaceutical therapies for osteoarthritis (OA) were focused on cartilage. However, it has been theorized that bone changes such as increased bone volume fraction and decreased bone matrix mineralization may play an important role in the initiation and pathogenesis of OA as well.

  8. Malalignment and subchondral bone turnover in contralateral knees of overweight/obese women with unilateral osteoarthritis: implications for bilateral disease.

    Science.gov (United States)

    Mazzuca, Steven A; Brandt, Kenneth D; Lane, Kathleen A; Chakr, Rafael

    2011-11-01

    To explore whether the risk of incident tibiofemoral (TF) osteoarthritis (OA) in the radiographically normal contralateral knee of overweight/obese women with unilateral knee OA is mediated by malalignment and/or preceded by increased turnover of subchondral bone. We used data of post hoc analyses from a randomized controlled trial. Cross-sectional analyses evaluated the baseline association between frontal plane alignment and bone turnover in the medial TF compartment in 78 radiographically normal contralateral knees. Longitudinal analyses ascertained whether incident radiographic OA (TF osteophyte formation within 30 months) was associated with malalignment and/or increased bone turnover at baseline. Alignment subcategories (varus/neutral/valgus) were based on the anatomic axis angle. (99m)Tc-methylene diphosphonate uptake in a late-phase bone scan was quantified in regions of interest in the medial tibia (MT) and medial femur (MF) and adjusted for uptake in a reference segment of the ipsilateral tibial shaft (TS). MF and MT uptake in varus contralateral knees was 50-55% greater than in the TS. Adjusted MT uptake in varus contralateral knees was significantly greater than that in neutral and valgus contralateral knees (mean 1.55 versus 1.38 and 1.43, respectively; P < 0.05). Among 69 contralateral knees followed longitudinally, 22 (32%) developed TF OA. Varus angulation was associated with a marginally significant increase in the odds of incident OA (adjusted odds ratio 3.98, P = 0.067). While the small sample size limited our ability to detect statistically significant risk factors, these data suggest that the risk of developing bilateral TF OA in overweight/obese women may be mediated by varus malalignment. Copyright © 2011 by the American College of Rheumatology.

  9. Thoroughbred horses in race training have lower levels of subchondral bone remodelling in highly loaded regions of the distal metacarpus compared to horses resting from training.

    Science.gov (United States)

    Holmes, J M; Mirams, M; Mackie, E J; Whitton, R C

    2014-12-01

    Bone is repaired by remodelling, a process influenced by its loading environment. The aim of this study was to investigate the effect of a change in loading environment on bone remodelling by quantifying bone resorption and formation activity in the metacarpal subchondral bone in Thoroughbred racehorses. Sections of the palmar metacarpal condyles of horses in race training (n = 24) or resting from training (n = 24) were examined with light microscopy and back scattered scanning electron microscopy (BSEM). Bone area fraction, osteoid perimeter and eroded bone surface were measured within two regions of interest: (1) the lateral parasagittal groove (PS); (2) the lateral condylar subchondral bone (LC). BSEM variables were analysed for the effect of group, region and interaction with time since change in work status. The means ± SE are reported. For both regions of interest in the training compared to the resting group, eroded bone surface was lower (PS: 0.39 ± 0.06 vs. 0.65 ± 0.07 per mm, P = 0.010; LC: 0.24 ± 0.04 vs. 0.85 ± 0.10 per mm, P Thoroughbred racehorses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Hyaluronan protects against cartilage damage by decreasing stiffness and changing3-D microarchitecture of subchondral bone in guinea pig primary osteoarthrosis

    DEFF Research Database (Denmark)

    Ding, Ming

    Daltons) intra-articular injection on subchondral bone tissues.   Methods: Fifty-six male guinea pigs (6.5 months of age) were randomly divided into 5 groups studied in a short-term and a long-term experimental period (Fig. 1). In the short-term study: HA-I group received intra-articular injection of HA 0.......4 mg/kg/week for 5 weeks in both knee joints; the control group received vehicle. In the long-term study: HA-II received 0.4mg/kg/week intra-articular injection for additional 5 weeks; HA-III received no more injection; and the control group received vehicle. After the injection periods the guinea pigs...... of HA on cartilage and subchondral bone were maintained when HA treatment was discontinued (Table 1).   Discussion: The current study has investigated the effects of HA on the properties of subchondral bone tissues in a primary guinea pig OA model. Significant positive effects of high molecular weight...

  11. Clinical outcomes in relation to locations of bone marrow edema lesions in patients with a subchondral insufficiency fracture of the hip: a review of fifteen cases.

    Science.gov (United States)

    Ikemura, Satoshi; Mawatari, Taro; Matsui, Gen; Iguchi, Takahiro; Mitsuyasu, Hiroaki

    2016-10-01

    The prognosis of patients with a subchondral insufficiency fracture remains unclear. The purpose of this study was to investigate the correlation between locations of bone marrow edema (BME) lesions and clinical outcome in patients with a subchondral insufficiency fracture of the hip. We retrospectively reviewed 15 consecutive hips in 14 patients who were diagnosed with subchondral insufficiency fracture of the hip at our institution between April 2013 and September 2014. This study included five males (six hips) and nine females (nine hips), ranging from 36 to 83 years of age (mean age: 66 years). The mean duration from the onset of hip pain to MRI examination was 1.8 months (range 0.5-5 months). Both clinical and imaging findings were investigated. Based on the findings of MR images, BME lesion in the femoral head alone was observed in six patients (six hips), BME lesion in the acetabulum alone was observed in one patient (two hips) and BME lesions in both the femoral head and acetabulum were observed in seven patients (seven hips). 3 of 15 hips resulted in rapidly destructive arthrosis and their BME lesions were observed in both the femoral head and acetabulum. 8 of 15 hips successfully healed by conservative treatment and BME lesions in 7 of these 8 hips were observed in only the femoral head or acetabulum. The results of this study indicate that the locations of BME lesions (femoral side alone, acetabular side alone or both) may be related to the clinical outcome in patients with a subchondral insufficiency fracture of the hip. Patients with subchondral insufficiency fracture of the hip in whom BME lesions were observed in both the femoral head and acetabulum may have a higher risk to need to undergo total hip arthroplasty.

  12. Cartilage Protective and Chondrogenic Capacity of WIN-34B, a New Herbal Agent, in the Collagenase-Induced Osteoarthritis Rabbit Model and in Progenitor Cells from Subchondral Bone

    Directory of Open Access Journals (Sweden)

    Jeong-Eun Huh

    2013-01-01

    Full Text Available We sought to determine the cartilage repair capacity of WIN-34B in the collagenase-induced osteoarthritis rabbit model and in progenitor cells from subchondral bone. The cartilage protective effect of WIN-34B was measured by clinical and histological scores, cartilage area, and proteoglycan and collagen contents in the collagenase-induced osteoarthritis rabbit model. The efficacy of chondrogenic differentiation of WIN-34B was assessed by expression of CD105, CD73, type II collagen, and aggrecan in vivo and was analyzed by the surface markers of progenitor cells, the mRNA levels of chondrogenic marker genes, and the level of proteoglycan, GAG, and type II collagen in vitro. Oral administration of WIN-34B significantly increased cartilage area, and this was associated with the recovery of proteoglycan and collagen content. Moreover, WIN-34B at 200 mg/kg significantly increased the expression of CD105, CD73, type II collagen, and aggrecan compared to the vehicle group. WIN-34B markedly enhanced the chondrogenic differentiation of CD105 and type II collagen in the progenitor cells from subchondral bone. Also, we confirmed that treatment with WIN-34B strongly increased the number of SH-2(CD105 cells and expression type II collagen in subchondral progenitor cells. Moreover, WIN-34B significantly increased proteoglycan, as measured by alcian blue staining; the mRNA level of type II α1 collagen, cartilage link protein, and aggrecan; and the inhibition of cartilage matrix molecules, such as GAG and type II collagen, in IL-1β-treated progenitor cells. These findings suggest that WIN-34B could be a potential candidate for effective anti-osteoarthritic therapy with cartilage repair as well as cartilage protection via enhancement of chondrogenic differentiation in the collagenase-induced osteoarthritis rabbit model and progenitor cells from subchondral bone.

  13. Dentoalveolar growth inhibition induced by bone denudation on palates: a study of two isolated cleft palates with asymmetric scar tissue distribution.

    Science.gov (United States)

    Ishikawa, H; Iwasaki, H; Tsukada, H; Chu, S; Nakamura, S; Yamamoto, K

    1999-09-01

    This report presents two cases of isolated cleft palate with asymmetric distribution of postsurgical scar tissue determined by laser Doppler flowmetry. To determine the effect of mucoperiosteal denudation of the bone on maxillary alveolar growth, the analysis of dentoalveolar structures compared the affected side to the unaffected side of each case. Two Japanese girls with isolated cleft palates were examined. Both subjects had undergone pushback operations (a modified version of the procedure of Wardill) for palatal repair at 18 months of age. Palatal blood flow was examined by laser Doppler flowmetry when the girls were 12 years old to determine the extent of postsurgical scar tissue over the denuded bone. To analyze the maxillary dentoalveolar structures three dimensionally, the whole surface of the upper dental cast was measured and recorded by an optical measuring device when the girls were 7 years old. Analysis via flowmetry showed that the palatal scar tissue area was limited to the anterior tooth region on the right (unaffected) side but extended posteriorly to the premolar region on the left (affected) side in both subjects. The two girls had similar dentoalveolar structures, with the dental and alveolar arches deflected lingually at the deciduous molar area on the affected side. There were no differences in the buccolingual inclination of deciduous molars or in the vertical growth of the alveolar processes between the affected and unaffected sides. In both girls, bone denudation in the premolar region appeared to result in less than 3 mm of displacement of the teeth palatally, with no change in lingual inclination. Any effects of scar tissue on the vertical development of the alveolus were not substantiated.

  14. Can we use subchondral bone thickness on high-field magnetic resonance images to identify Thoroughbred racehorses at risk of catastrophic lateral condylar fracture?

    Science.gov (United States)

    Tranquille, C A; Murray, R C; Parkin, T D H

    2017-03-01

    Fractures of the lateral condyle of the third metacarpus (MC3) are a significant welfare concern in horseracing worldwide. The primary aim of this work was to identify magnetic resonance (MR) image-detectable prefracture markers that have the potential for use as a screening tool to identify horses at significant risk of catastrophic fracture. Case-control study of bone-level risk factors for fracture in racehorses. A total of 191 MC3s from horses, with and without lateral condylar fracture of MC3, were subjected to MR imaging. The depth of dense subchondral/trabecular bone was measured at several sites around the distal end of the bone and regression analyses were conducted to identify differences in this depth between horses with and without lateral condylar fracture. Greater depth of dense subchondral/trabecular bone in the palmar half of the lateral parasagittal groove of distal MC3 was associated with an increased likelihood of being from a horse that had sustained a fracture. Receiver operator characteristic analysis was used to identify the optimal cut-off in the depth of dense subchondral/trabecular bone at this site to best discriminate fracture status. Positive and negative predictive values were calculated using the prevalence of fracture within the current study and also a prevalence estimate for the wider racehorse population. There is a requirement to identify suitable prescreening test(s) to eliminate many true negative horses and increase the prevalence of prefracture pathology in the sub population that would be screened using MR imaging, in turn maximising the positive predictive value of this test. © 2016 EVJ Ltd.

  15. Computed Tomographic Imaging of Subchondral Fatigue Cracks in the Distal End of the Third Metacarpal Bone in the Thoroughbred Racehorse Can Predict Crack Micromotion in an Ex-Vivo Model

    Science.gov (United States)

    Dubois, Marie-Soleil; Morello, Samantha; Rayment, Kelsey; Markel, Mark D.; Vanderby, Ray; Kalscheur, Vicki L.; Hao, Zhengling; McCabe, Ronald P.; Marquis, Patricia; Muir, Peter

    2014-01-01

    Articular stress fracture arising from the distal end of the third metacarpal bone (MC3) is a common serious injury in Thoroughbred racehorses. Currently, there is no method for predicting fracture risk clinically. We describe an ex-vivo biomechanical model in which we measured subchondral crack micromotion under compressive loading that modeled high speed running. Using this model, we determined the relationship between subchondral crack dimensions measured using computed tomography (CT) and crack micromotion. Thoracic limbs from 40 Thoroughbred racehorses that had sustained a catastrophic injury were studied. Limbs were radiographed and examined using CT. Parasagittal subchondral fatigue crack dimensions were measured on CT images using image analysis software. MC3 bones with fatigue cracks were tested using five cycles of compressive loading at -7,500N (38 condyles, 18 horses). Crack motion was recorded using an extensometer. Mechanical testing was validated using bones with 3 mm and 5 mm deep parasagittal subchondral slots that modeled naturally occurring fatigue cracks. After testing, subchondral crack density was determined histologically. Creation of parasagittal subchondral slots induced significant micromotion during loading (pThoroughbred horses in-vivo to assess risk of condylar fracture. Horses with parasagittal crack arrays that exceed 30 mm2 may have a high risk for development of condylar fracture. PMID:25077477

  16. A decreased subchondral trabecular bone tissue elastic modulus is associated with pre-arthritic cartilage damage

    DEFF Research Database (Denmark)

    Day, J; Ding, Ming; van der Linden, JC

    2001-01-01

    determined using a combination of finite element models and mechanical testing. The bone tissue modulus was reduced by 60% in the medial condyle of the cases with cartilage damage compared to the control specimens. Neither the presence of cartilage damage nor the anatomic site (medial vs. lateral) affected...

  17. Modulation of insulin-like growth factor 1 levels in human osteoarthritic subchondral bone osteoblasts.

    Science.gov (United States)

    Massicotte, Frédéric; Fernandes, Julio Cesar; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Lajeunesse, Daniel

    2006-03-01

    Human osteoarthritis (OA) is characterized by cartilage loss, bone sclerosis, osteophyte formation and inflammation of the synovial membrane. We previously reported that OA osteoblasts (Ob) show abnormal phenotypic characteristics possibly responsible for bone sclerosis and that two subgroups of OA patients can be identified by low or high endogenous production of prostaglandin E2 (PGE2) by OA Ob. Here, we determined that the elevated PGE2 levels in the high OA subgroup were linked with enhanced cyclooxygenase-2 (COX-2) protein levels compared to normal and low OA Ob. A linear relationship was observed between endogenous PGE2 levels and insulin-like growth factor 1 (IGF-1) levels in OA Ob. As parathyroid hormone (PTH) and PGE2 are known stimulators of IGF-1 production in Ob, we next evaluated their effect in OA Ob. Both subgroups increased their IGF-1 production similarly in response to PGE2, while the high OA subgroup showed a blunted response to PTH compared to the low OA group. Conversely, only the high OA group showed a significant inhibition of IGF-1 production when PGE2 synthesis was reduced with Naproxen, a non-steroidal antiinflammatory drug (NSAID) that inhibits cyclooxygenases (COX). The PGE2-dependent stimulation of IGF-1 synthesis was due in part to the cAMP/protein kinase A pathway since both the direct inhibition of this pathway with H-89 and the inhibition of EP2 or EP4 receptors, linked to cAMP production, reduced IGF-1 synthesis. The production of the most abundant IGF-1 binding proteins (IGFBPs) in bone tissue, IGFBP-3, -4, and -5, was lower in OA compared to normal Ob independently of the OA group. Under basal condition, OA Ob expressed similar IGF-1 mRNA to normal Ob; however, PGE2 stimulated IGF-1 mRNA expression more in OA than normal Ob. These data suggest that increased IGF-1 levels correlate with elevated endogenous PGE2 levels in OA Ob and that higher IGF-1 levels in OA Ob could be important for bone sclerosis in OA.

  18. Computed tomographic imaging of subchondral fatigue cracks in the distal end of the third metacarpal bone in the thoroughbred racehorse can predict crack micromotion in an ex-vivo model.

    Directory of Open Access Journals (Sweden)

    Marie-Soleil Dubois

    Full Text Available Articular stress fracture arising from the distal end of the third metacarpal bone (MC3 is a common serious injury in Thoroughbred racehorses. Currently, there is no method for predicting fracture risk clinically. We describe an ex-vivo biomechanical model in which we measured subchondral crack micromotion under compressive loading that modeled high speed running. Using this model, we determined the relationship between subchondral crack dimensions measured using computed tomography (CT and crack micromotion. Thoracic limbs from 40 Thoroughbred racehorses that had sustained a catastrophic injury were studied. Limbs were radiographed and examined using CT. Parasagittal subchondral fatigue crack dimensions were measured on CT images using image analysis software. MC3 bones with fatigue cracks were tested using five cycles of compressive loading at -7,500N (38 condyles, 18 horses. Crack motion was recorded using an extensometer. Mechanical testing was validated using bones with 3 mm and 5 mm deep parasagittal subchondral slots that modeled naturally occurring fatigue cracks. After testing, subchondral crack density was determined histologically. Creation of parasagittal subchondral slots induced significant micromotion during loading (p<0.001. In our biomechanical model, we found a significant positive correlation between extensometer micromotion and parasagittal crack area derived from reconstructed CT images (SR = 0.32, p<0.05. Correlations with transverse and frontal plane crack lengths were not significant. Histologic fatigue damage was not significantly correlated with crack dimensions determined by CT or extensometer micromotion. Bones with parasagittal crack area measurements above 30 mm2 may have a high risk of crack propagation and condylar fracture in vivo because of crack micromotion. In conclusion, our results suggest that CT could be used to quantify subchondral fatigue crack dimensions in racing Thoroughbred horses in-vivo to

  19. Computed tomographic imaging of subchondral fatigue cracks in the distal end of the third metacarpal bone in the thoroughbred racehorse can predict crack micromotion in an ex-vivo model.

    Science.gov (United States)

    Dubois, Marie-Soleil; Morello, Samantha; Rayment, Kelsey; Markel, Mark D; Vanderby, Ray; Kalscheur, Vicki L; Hao, Zhengling; McCabe, Ronald P; Marquis, Patricia; Muir, Peter

    2014-01-01

    Articular stress fracture arising from the distal end of the third metacarpal bone (MC3) is a common serious injury in Thoroughbred racehorses. Currently, there is no method for predicting fracture risk clinically. We describe an ex-vivo biomechanical model in which we measured subchondral crack micromotion under compressive loading that modeled high speed running. Using this model, we determined the relationship between subchondral crack dimensions measured using computed tomography (CT) and crack micromotion. Thoracic limbs from 40 Thoroughbred racehorses that had sustained a catastrophic injury were studied. Limbs were radiographed and examined using CT. Parasagittal subchondral fatigue crack dimensions were measured on CT images using image analysis software. MC3 bones with fatigue cracks were tested using five cycles of compressive loading at -7,500N (38 condyles, 18 horses). Crack motion was recorded using an extensometer. Mechanical testing was validated using bones with 3 mm and 5 mm deep parasagittal subchondral slots that modeled naturally occurring fatigue cracks. After testing, subchondral crack density was determined histologically. Creation of parasagittal subchondral slots induced significant micromotion during loading (pBones with parasagittal crack area measurements above 30 mm2 may have a high risk of crack propagation and condylar fracture in vivo because of crack micromotion. In conclusion, our results suggest that CT could be used to quantify subchondral fatigue crack dimensions in racing Thoroughbred horses in-vivo to assess risk of condylar fracture. Horses with parasagittal crack arrays that exceed 30 mm2 may have a high risk for development of condylar fracture.

  20. Spinacia oleracea extract attenuates disease progression and sub-chondral bone changes in monosodium iodoacetate-induced osteoarthritis in rats.

    Science.gov (United States)

    Choudhary, Dharmendra; Kothari, Priyanka; Tripathi, Ashish Kumar; Singh, Sonu; Adhikary, Sulekha; Ahmad, Naseer; Kumar, Sudhir; Dev, Kapil; Mishra, Vijay Kumar; Shukla, Shubha; Maurya, Rakesh; Mishra, Prabhat R; Trivedi, Ritu

    2018-02-20

    Spinacia oleracea is an important dietary vegetable in India and throughout the world and has many beneficial effects. It is cultivated globally. However, its effect on osteoarthritis that mainly targets the cartilage cells remains unknown. In this study we aimed to evaluate the anti-osteoarthritic and chondro-protective effects of SOE on chemically induced osteoarthritis (OA). OA was induced by intra-patellar injection of monosodium iodoacetate (MIA) at the knee joint in rats. SOE was then given orally at 250 and 500 mg.kg - 1  day - 1 doses for 28 days to these rats. Anti-osteoarthritic potential of SOE was evaluated by micro-CT, mRNA and protein expression of pro-inflammatory and chondrogenic genes, clinically relevant biomarker's and behavioural experiments. In vitro cell free and cell based assays indicated that SOE acts as a strong anti-oxidant and an anti-inflammatory agent. Histological analysis of knee joints at the end of the experiment by safranin-o and toluidine blue staining established its protective effect. Radiological data corroborated the findings with improvement in the joint space and irregularity of the articular and atrophied femoral condyles and tibial plateau. Micro-CT analysis of sub-chondral bone indicated that SOE had the ability to mitigate OA effects by increasing bone volume to tissue volume (BV/TV) which resulted in decrease of trabecular pattern factor (Tb.Pf) by more than 200%. SOE stimulated chondrogenic marker gene expression with reduction in pro-inflammatory markers. Purified compounds isolated from SOE exhibited increased Sox-9 and Col-II protein expression in articular chondrocytes. Serum and urine analysis indicated that SOE had the potential to down-regulate glutathione S-transferase (GST) activity, clinical markers of osteoarthritis like cartilage oligometric matrix protein (COMP) and CTX-II. Overall, this led to a significant improvement in locomotion and balancing activity in rats as assessed by Open-field and Rota

  1. Magnetic resonance perfusion and diffusion imaging characteristics of transient bone marrow edema, avascular necrosis and subchondral insufficiency fractures of the proximal femur

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Dirk, E-mail: d.mueller@uk-koeln.de [Department of Radiology, University of Cologne (Germany); Department of Radiology, Technische Universität München (Germany); Schaeffeler, Christoph, E-mail: schaeffeler@me.com [Department of Radiology, Cantonal Hospital Graubuenden, Chur (Switzerland); Department of Radiology, Cantonal Hospital Graubuenden, Chur (Switzerland); Baum, Thomas, E-mail: thomas-baum@gmx.de [Department of Radiology, Technische Universität München (Germany); Walter, Flavia, E-mail: flavia_walter2000@yahoo.de [Department of Radiology, Technische Universität München (Germany); Rechl, Hans, E-mail: rechl@tum.de [Department of Orthopaedics, Technische Universität München (Germany); Rummeny, Ernst J., E-mail: rummeny@tum.de [Department of Radiology, Technische Universität München (Germany); Woertler, Klaus, E-mail: klaus.woertler@tum.de [Department of Radiology, Technische Universität München (Germany)

    2014-10-15

    Highlights: • DCE-MRI may add information to the pathophysiology of bone marrow edema (BME) of the proximal femur. • Patients with transient bone marrow edema (TBME) or subchondral insufficiency fractures (SIF) and avascular osteonecrosis (AVN) showed different MR perfusion patterns. • Perfusion characteristics suggest different pathophysiology for AVN compared with TBME or SIF. • Diffusion weighted imaging (DWI) was not able to discriminate necrotic from edematous bone marrow. • DWI is of limited value to evaluate BME of the proximal femur. - Abstract: Purpose: To evaluate magnetic resonance (MR) perfusion and diffusion imaging characteristics in patients with transient bone marrow edema (TBME), avascular necrosis (AVN), or subchondral insufficiency fractures (SIF) of the proximal femur. Materials and methods: 29 patients with painful hip and bone marrow edema pattern of the proximal femur on non-contrast MR imaging were examined using diffusion-weighted and dynamic gadolinium-enhanced sequences. Apparent diffusion coefficients (ADCs) and perfusion parameters were calculated for different regions of the proximal femur. Regional distribution and differences in ADC values and perfusion parameters were evaluated. Results: Seven patients presented with TBME, 15 with AVN and seven with SIF of the proximal femur. Perfusion imaging showed significant differences for maximum enhancement values (E{sub max}), slope (E{sub slope}) and time to peak (TTP) between the three patient groups (p < 0.05). In contrast, no significant differences for ADC values were calculated when comparing TBME, AVN, and SIF patients. Conclusion: Diffusion weighted imaging of bone marrow of the proximal femur did not show significant differences between patients with TBME, AVN or SIF. In contrast, MR perfusion imaging demonstrated significant differences for the different patient groups and may as a complementary imaging technique add information to the understanding of the pathophysiology

  2. Magnetic resonance perfusion and diffusion imaging characteristics of transient bone marrow edema, avascular necrosis and subchondral insufficiency fractures of the proximal femur

    International Nuclear Information System (INIS)

    Mueller, Dirk; Schaeffeler, Christoph; Baum, Thomas; Walter, Flavia; Rechl, Hans; Rummeny, Ernst J.; Woertler, Klaus

    2014-01-01

    Highlights: • DCE-MRI may add information to the pathophysiology of bone marrow edema (BME) of the proximal femur. • Patients with transient bone marrow edema (TBME) or subchondral insufficiency fractures (SIF) and avascular osteonecrosis (AVN) showed different MR perfusion patterns. • Perfusion characteristics suggest different pathophysiology for AVN compared with TBME or SIF. • Diffusion weighted imaging (DWI) was not able to discriminate necrotic from edematous bone marrow. • DWI is of limited value to evaluate BME of the proximal femur. - Abstract: Purpose: To evaluate magnetic resonance (MR) perfusion and diffusion imaging characteristics in patients with transient bone marrow edema (TBME), avascular necrosis (AVN), or subchondral insufficiency fractures (SIF) of the proximal femur. Materials and methods: 29 patients with painful hip and bone marrow edema pattern of the proximal femur on non-contrast MR imaging were examined using diffusion-weighted and dynamic gadolinium-enhanced sequences. Apparent diffusion coefficients (ADCs) and perfusion parameters were calculated for different regions of the proximal femur. Regional distribution and differences in ADC values and perfusion parameters were evaluated. Results: Seven patients presented with TBME, 15 with AVN and seven with SIF of the proximal femur. Perfusion imaging showed significant differences for maximum enhancement values (E max ), slope (E slope ) and time to peak (TTP) between the three patient groups (p < 0.05). In contrast, no significant differences for ADC values were calculated when comparing TBME, AVN, and SIF patients. Conclusion: Diffusion weighted imaging of bone marrow of the proximal femur did not show significant differences between patients with TBME, AVN or SIF. In contrast, MR perfusion imaging demonstrated significant differences for the different patient groups and may as a complementary imaging technique add information to the understanding of the pathophysiology of

  3. Subchondral insufficiency fracture of the knee: a non-traumatic injury with prolonged recovery time

    OpenAIRE

    Gourlay, Margaret L; Renner, Jordan B; Spang, Jeffrey T; Rubin, Janet E

    2015-01-01

    Subchondral insufficiency fractures are non-traumatic fractures that occur immediately below the cartilage of a joint. Although low bone density may be present concurrently, it is not the underlying cause of subchondral insufficiency fractures in the majority of patients. Patients with subchondral insufficiency fracture characteristically have unremarkable plain radiographs, while MRI examination may reveal extensive bone marrow oedema and subchondral bone collapse. This article presents a 51...

  4. Molecular changes in articular cartilage and subchondral bone in the rat anterior cruciate ligament transection and meniscectomized models of osteoarthritis

    OpenAIRE

    Zhuo Ya; Hayami Tadashi; Pickarski Maureen; Duong Le T

    2011-01-01

    Abstract Background Osteoarthritis (OA) is a debilitating, progressive joint disease. Methods Similar to the disease progression in humans, sequential events of early cartilage degradation, subchondral osteopenia followed by sclerosis, and late osteophyte formation were demonstrated in the anterior cruciate ligament transection (ACLT) or ACLT with partial medial meniscectomy (ACLT + MMx) rat OA models. We describe a reliable and consistent method to examine the time dependent changes in the g...

  5. Morphological studies at subchondral bone structures in human early arthrosis. Final report; Morphologische Studien an subchondralen Knochenstrukturen bei humanen Frueharthrosen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-12-31

    Quantitative histomorphometric studies using an image analysis system were performed simultaneously on hyaline cartilage, calcified cartilage and subchondral cancellous bone of human tibial heads for detailed information about the pathogenesis of arthrosis. Joint structures need to be fully detected in three dimensions since measurement values are more affected by topographical aspects than by either age, or sex, or arthrosin stage. Mechanical factors were found to affect essentially the initiation and progression of arthrosis. Results are demonstrated in detail. (orig.) [Deutsch] Um detaillierte Aussagen ueber die Pathogenese der Arthrose machen zu koennen, wurden hyaliner Knorpel, Kalkknorpel und subchondrale Spongiosa menschlicher Tibiakoepfe gleichzeitig mit Hilfe eines Bildanalysesystems quantitativ histomorphometrisch untersucht. Eine umfangreiche dreidimensionale Erfassung der Gelenkstrukturen ist erforderlich, da sich topographische Aspekte wesentlich staerker auf die Messwerte auswirken als Alter, Geschlecht oder Arthrosestadium. Insgesamt zeigt sich ein wesentlicher Einfluss mechanischer Faktoren auf die Arthroseinitiierung und -progredienz. Die Ergebnisse werden detailliert dargestellt. (orig.)

  6. Joint unloading implant modifies subchondral bone trabecular structure in medial knee osteoarthritis: 2-year outcomes of a pilot study using fractal signature analysis

    Directory of Open Access Journals (Sweden)

    Miller LE

    2015-01-01

    Full Text Available Larry E Miller,1,2 Miki Sode,3 Thomas Fuerst,3 Jon E Block2 1Miller Scientific Consulting, Inc., Asheville, NC, USA; 2The Jon Block Group, San Francisco, CA, USA; 3Bioclinica, Newark, CA, USA Background: Knee osteoarthritis (OA is largely attributable to chronic excessive and aberrant joint loading. The purpose of this pilot study was to quantify radiographic changes in subchondral bone after treatment with a minimally invasive joint unloading implant (KineSpring® Knee Implant System.Methods: Nine patients with unilateral medial knee OA resistant to nonsurgical therapy were treated with the KineSpring System and followed for 2 years. Main outcomes included Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC pain, function, and stiffness subscores and independent core laboratory determinations of joint space width and fractal signature of the tibial cortex.Results: WOMAC scores, on average, improved by 92% for pain, 91% for function, and 79% for stiffness over the 2-year follow-up period. Joint space width in the medial compartment of the treated knee significantly increased from 0.9 mm at baseline to 3.1 mm at 2 years; joint space width in the medial compartment of the untreated knee was unchanged. Fractal signatures of the vertically oriented trabeculae in the medial compartment decreased by 2.8% in the treated knee and increased by 2.1% in the untreated knee over 2 years. No statistically significant fractal signature changes were observed in the horizontally oriented trabeculae in the medial compartment or in the horizontal or vertical trabeculae of the lateral compartment in the treated knee.Conclusion: Preliminary evidence suggests that the KineSpring System may modify knee OA disease progression by increasing joint space width and improving subchondral bone trabecular integrity, thereby reducing pain and improving joint function. Keywords: disease modification, KineSpring, joint space, pain, trabecular

  7. Application of in vivo micro-computed tomography in the temporal characterisation of subchondral bone architecture in a rat model of low-dose monosodium iodoacetate-induced osteoarthritis

    Science.gov (United States)

    2011-01-01

    Introduction Osteoarthritis (OA) is a complex, multifactorial joint disease affecting both the cartilage and the subchondral bone. Animal models of OA aid in the understanding of the pathogenesis of OA and testing suitable drugs for OA treatment. In this study we characterized the temporal changes in the tibial subchondral bone architecture in a rat model of low-dose monosodium iodoacetate (MIA)-induced OA using in vivo micro-computed tomography (CT). Methods Male Wistar rats received a single intra-articular injection of low-dose MIA (0.2 mg) in the right knee joint and sterile saline in the left knee joint. The animals were scanned in vivo by micro-CT at two, six, and ten weeks post-injection, analogous to early, intermediate, and advanced stages of OA, to assess architectural changes in the tibial subchondral bone. The articular cartilage changes in the tibiae were assessed macroscopically and histologically at ten weeks post-injection. Results Interestingly, tibiae of the MIA-injected knees showed significant bone loss at two weeks, followed by increased trabecular thickness and separation at six and ten weeks. The trabecular number was decreased at all time points compared to control tibiae. The tibial subchondral plate thickness of the MIA-injected knee was increased at two and six weeks and the plate porosity was increased at all time points compared to control. At ten weeks, histology revealed loss of proteoglycans, chondrocyte necrosis, chondrocyte clusters, cartilage fibrillation, and delamination in the MIA-injected tibiae, whereas the control tibiae showed no changes. Micro-CT images and histology showed the presence of subchondral bone sclerosis, cysts, and osteophytes. Conclusions These findings demonstrate that the low-dose MIA rat model closely mimics the pathological features of progressive human OA. The low-dose MIA rat model is therefore suitable to study the effect of therapeutic drugs on cartilage and bone in a non-trauma model of OA. In vivo

  8. A novel method to assess subchondral bone formation using [18F]NaF-PET in the evaluation of knee degeneration.

    Science.gov (United States)

    Jonnakuti, Venkata S; Raynor, William Y; Taratuta, Elena; Werner, Thomas J; Alavi, Abass; Baker, Joshua F

    2018-05-01

    Fluorine-18-sodium fluoride-PET ([F]NaF-PET) facilitates direct assessment of subchondral bone formation to evaluate degeneration in articulating joints. No standards exist for the quantification of joint activity using [F]NaF-PET, and many techniques rely on focal uptake to characterize an entire region of interest. This study proposes a novel method of quantitative global knee analysis to assess regions of expected bone remodeling in the evaluation of knee degeneration. The study population consisted of 18 patients with rheumatoid arthritis who underwent [F]NaF-PET/computed tomography imaging. The maximum standardized uptake value (knee SUVmax) in addition to a target-to-background ratio (TBR) that represents global knee activity adjusted for systemic bone formation measured at the lateral femoral neck (global knee TBR) were calculated. A radiologist scored standard radiographs of the knee in nine patients using the Kellgren-Lawrence grading system. Patients with greater [F]NaF uptake demonstrated greater knee deterioration, which was corroborated by the radiograph findings. Average Kellgren-Lawrence grading was strongly associated with both global knee TBR (Spearman ρ=0.69, P=0.04) and knee SUVmax scores (Spearman ρ=0.93, P=0.0003). Assessment of global activity within the joint is a feasible and clinically useful technique for characterizing disease activity with a single value. Furthermore, a ratio based on systemic bone turnover in a nonarticulating, weight-bearing site adjusts for differences in bone formation related to bodyweight or metabolic bone diseases. We hypothesize that a global knee TBR score may be more sensitive at detecting changes in disease progression, as new spatially distinct lesions with a lower SUV that develop within an region of interest would not be detected by the SUVmax methodology. Longitudinal studies assessing sensitivity with larger patient cohorts are needed to further validate this methodology.

  9. In vitro assessment of biomaterial-induced remodeling of subchondral and cancellous bone for the early intervention of joint degeneration with focus on the spinal disc

    Science.gov (United States)

    McCanless, Jonathan D.

    Osteoarthritis-associated pain of the spinal disc, knee, and hip derives from degeneration of cartilagenous tissues in these joints. Traditional therapies have focused on these cartilage (and disc specific nucleus pulposus) changes as a means of treatment through tissue grafting, regenerative synthetic implants, non-regenerative space filling implants, arthroplasty, and arthrodesis. Although such approaches may seem apparent upon initial consideration of joint degeneration, tissue pathology has shown changes in the underlying bone and vascular bed precede the onset of cartilaginous changes. It is hypothesized that these changes precedent joint degeneration and as such may provide a route for early prevention. The current work proposes an injectable biomaterial-based therapy within these subchondral and cancellous bone regions as a means of preventing or reversing osteoarthritis. Two human concentrated platelet releasate-containing alginate hydrogel/beta-tricalcium phosphate composites have been developed for this potential biomaterial application. The undertaking of assessing these materials through bench-, in vitro, and ex vivo work is described herein. These studies showed the capability of the biomaterials to initiate a wound healing response in monocytes, angiogenic and differentiation behavior in immature endothelial cells, and early osteochondral differentiation in mesenchymal stem cells. These cellular activities are associated with fracture healing and endochondral bone formation, demonstrating the potential of the biomaterials to induce osseous and vascular tissue remodeling underlying osteoarthritic joints as a novel therapy for a disease with rapidly growing healthcare costs.

  10. Positive effect of removal of subchondral bone plate for cemented acetabular component fixation in total hip arthroplasty: a randomised RSA study with ten-year follow-up.

    Science.gov (United States)

    Flivik, G; Kristiansson, I; Ryd, L

    2015-01-01

    We hypothesised that the removal of the subchondral bone plate (SCBP) for cemented acetabular component fixation in total hip arthroplasty (THA) offers advantages over retention by improving the cement-bone interface, without jeopardising implant stability. We have previously published two-year follow-up data of a randomised controlled trial (RCT), in which 50 patients with primary osteoarthritis were randomised to either retention or removal of the SCBP. The mean age of the retention group (n = 25, 13 males) was 70.0 years (sd 6.8). The mean age in the removal group (n = 25, 16 males) was 70.3 years (sd 7.9). Now we have followed up the patients at six (retention group, n = 21; removal group, n = 20) and ten years (retention group: n = 17, removal group: n = 18), administering clinical outcome questionnaires and radiostereometric analysis (RSA), and determining the presence of radiolucent lines (RLLs) on conventional radiographs. RSA demonstrated similar translation and rotation patterns up to six years. Between six and ten years, proximal acetabular component migration and changes of inclination were larger in the retention group, although the mean differences did not reach statistical significance. Differences in migration were driven by two patients in the SCBP retention group with extensive migration versus none in the SCBP removal group. The significant difference (p < 0.001) in the development of radiolucent lines in the retention group, previously observed at two years, increased even further during the course of follow-up (p < 0.001). While recognising SCBP removal is a more demanding technique, we conclude that, wherever possible, the SCBP should be removed to improve the cement-bone interface in order to maximise acetabular component stability and longevity. ©2015 The British Editorial Society of Bone & Joint Surgery.

  11. Carnosol Inhibits Pro-Inflammatory and Catabolic Mediators of Cartilage Breakdown in Human Osteoarthritic Chondrocytes and Mediates Cross-Talk between Subchondral Bone Osteoblasts and Chondrocytes.

    Directory of Open Access Journals (Sweden)

    Christelle Sanchez

    Full Text Available The aim of this work was to evaluate the effects of carnosol, a rosemary polyphenol, on pro-inflammatory and catabolic mediators of cartilage breakdown in chondrocytes and via bone-cartilage crosstalk.Osteoarthritic (OA human chondrocytes were cultured in alginate beads for 4 days in presence or absence of carnosol (6 nM to 9 μM. The production of aggrecan, matrix metalloproteinase (MMP-3, tissue inhibitor of metalloproteinase (TIMP-1, interleukin (IL-6 and nitric oxide (NO and the expression of type II collagen and ADAMTS-4 and -5 were analyzed. Human osteoblasts from sclerotic (SC or non-sclerotic (NSC subchondral bone were cultured for 3 days in presence or absence of carnosol before co-culture with chondrocytes. Chondrocyte gene expression was analyzed after 4 days of co-culture.In chondrocytes, type II collagen expression was significantly enhanced in the presence of 3 μM carnosol (p = 0.008. MMP-3, IL-6, NO production and ADAMTS-4 expression were down-regulated in a concentration-dependent manner by carnosol (p<0.01. TIMP-1 production was slightly increased at 3 μM (p = 0.02 and ADAMTS-5 expression was decreased from 0.2 to 9 μM carnosol (p<0.05. IL-6 and PGE2 production was reduced in the presence of carnosol in both SC and NSC osteoblasts while alkaline phosphatase activity was not changed. In co-culture experiments preincubation of NSC and SC osteoblasts wih carnosol resulted in similar effects to incubation with anti-IL-6 antibody, namely a significant increase in aggrecan and decrease in MMP-3, ADAMTS-4 and -5 gene expression by chondrocytes.Carnosol showed potent inhibition of pro-inflammatory and catabolic mediators of cartilage breakdown in chondrocytes. Inhibition of matrix degradation and enhancement of formation was observed in chondrocytes cocultured with subchondral osteoblasts preincubated with carnosol indicating a cross-talk between these two cellular compartments, potentially mediated via inhibition of IL-6 in

  12. Relationships between in vivo dynamic knee joint loading, static alignment and tibial subchondral bone microarchitecture in end-stage knee osteoarthritis.

    Science.gov (United States)

    Roberts, B C; Solomon, L B; Mercer, G; Reynolds, K J; Thewlis, D; Perilli, E

    2018-04-01

    To study, in end-stage knee osteoarthritis (OA) patients, relationships between indices of in vivo dynamic knee joint loads obtained pre-operatively using gait analysis, static knee alignment, and the subchondral trabecular bone (STB) microarchitecture of their excised tibial plateau quantified with 3D micro-CT. Twenty-five knee OA patients scheduled for total knee arthroplasty underwent pre-operative gait analysis. Mechanical axis deviation (MAD) was determined radiographically. Following surgery, excised tibial plateaus were micro-CT-scanned and STB microarchitecture analysed in four subregions (anteromedial, posteromedial, anterolateral, posterolateral). Regional differences in STB microarchitecture and relationships between joint loading and microarchitecture were examined. STB microarchitecture differed among subregions (P knee adduction moment (KAM) and internal rotation moment (|r|-range: 0.54-0.74). When controlling for walking speed, KAM and MAD, the ERM explained additional 11-30% of the variations in anteromedial BV/TV and medial-to-lateral BV/TV ratio (R 2  = 0.59, R 2  = 0.69, P knee joint loading indices in end-stage knee OA patients. Particularly, anteromedial BV/TV correlates strongest with ERM, whereas medial-to-lateral BV/TV ratio correlates strongest with indicators of medial-to-lateral joint loading (MAD, KAM) and rotational moments. However, associations with ERM should be interpreted with caution. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  13. A role for subchondral bone changes in the process of osteoarthritis; a micro-CT study of two canine models

    NARCIS (Netherlands)

    Y.H. Sniekers (Yvonne); F. Intema (Femke); F.P.J.G. Lafeber (Floris); G.J.V.M. van Osch (Gerjo); J.P.T.M. van Leeuwen (Hans); H.H. Weinans (Harrie); S.C. Mastbergen (Simon)

    2008-01-01

    textabstractBACKGROUND: This study evaluates changes in peri-articular bone in two canine models for osteoarthritis: the groove model and the anterior cruciate ligament transection (ACLT) model. METHODS: Evaluation was performed at 10 and 20 weeks post-surgery and in addition a 3-weeks time point

  14. MRI of subchondral fractures: a review

    Energy Technology Data Exchange (ETDEWEB)

    Lopes Viana, Sergio [Hospital Ortopedico e Medicina Especializada (HOME) and Hospital da Crianca de Brasilia Jose Alencar, Brasilia, DF (Brazil); Beber Machado, Bruno [Clinica Radiologica Med Imagem, Unimed Sul Capixaba and Santa Casa de Misericordia de Cachoeiro de Itapemirim, Cachoeiro de Itapemirim (Brazil); Mendlovitz, Paulo Sergio [Hospital Universitario de Brasilia (Universidade de Brasilia) and Radiologia Anchieta, Brasilia (Brazil)

    2014-11-15

    Several authors have recently emphasized the role of magnetic resonance imaging (MRI) in the diagnosis of subchondral fractures. There is increasing interest about this type of fractures, mostly because they have been implicated in the genesis of some well-known destructive articular conditions whose cause was previously undetermined, such as distal clavicular osteolysis, rapidly progressive osteoarthritis of the hip, spontaneous osteonecrosis of the knee and adult-type Freiberg's infraction. Subchondral fractures may ultimately lead to bone collapse, secondary osteonecrosis and severe articular damage, and there may be rapid progression of joint destruction over a period of weeks to months. It has been suggested that timely diagnosis might potentially improve the outcome and avoid the onset of destructive joint disease, making MRI even more important in this setting. The fracture line usually appears as a band of low signal intensity in the subchondral bone plate, adjacent to the articular surface, most often surrounded by bone marrow edema. In this article the authors review the most relevant imaging features of subchondral fractures in several joints, stressing the importance of early recognition for a better outcome. (orig.)

  15. The effects of different doses of IGF-1 on cartilage and subchondral bone during the repair of full-thickness articular cartilage defects in rabbits.

    Science.gov (United States)

    Zhang, Z; Li, L; Yang, W; Cao, Y; Shi, Y; Li, X; Zhang, Q

    2017-02-01

    To investigate the effects of different doses of insulin-like growth factor 1 (IGF-1) on the cartilage layer and subchondral bone (SB) during repair of full-thickness articular cartilage (AC) defects. IGF-1-loaded collagen membrane was implanted into full-thickness AC defects in rabbits. The effects of two different doses of IGF-1 on cartilage layer and SB adjacent to the defect, the cartilage structure, formation and integration, and the new SB formation were evaluated at the 1st, 4th and 8th week postoperation. Meanwhile, after 1 week treatment, the relative mRNA expressions in tissues adjacent to the defect, including cartilage and SB were determined by quantitative real-time RT-PCR (qRT-PCR), respectively. Different doses of IGF-1 induced different gene expression profiles in tissues adjacent to the defect and resulted in different repair outcomes. Particularly, at high dose IGF-1 aided cell survival, regulated the gene expressions in cartilage layer adjacent defect and altered ECM composition more effectively, improved the formation and integrity of neo-cartilage. While, at low dose IGF-1 regulated the gene expressions in SB more efficaciously and subsequently promoted the SB remodeling and reconstruction. Different doses of IGF-1 induced different responses of cartilage or SB during the repair of full-thickness AC defects. Particularly, high dose of IGF-1 was more beneficial to the neo-cartilage formation and integration, while low dose of it was more effective for the SB formation. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  16. Subchondral insufficiency fractures of the femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Davies, M.; Cassar-Pullicino, V.N. [Department of Radiology, Robert Jones and Agnes Hunt Orthopaedic and District Hospital, Oswestry, SY10 7AG, Shropshire (United Kingdom); Darby, A.J. [Department of Pathology, Robert Jones and Agnes Hunt Orthopaedic and District Hospital, Oswestry, SY10 7AG, Shropshire (United Kingdom)

    2004-02-01

    The aim of this study was to increase awareness of, and to show the variable clinical and radiological features of, subchondral insufficiency fractures of the femoral head. The clinical and radiological findings in 7 patients with subchondral insufficiency fractures of the femoral head were reviewed retrospectively. The diagnosis was confirmed histologically in 4 patients. Radiographs were performed in all patients, MRI in 5 and scintigraphy in 4 patients. Radiographs showed varying degrees of femoral head collapse in 4 patients. In the remaining 3 patients radiographs showed a normal femoral head, regional osteoporosis and focal sclerosis, respectively. Magnetic resonance imaging showed a low-signal band on T1- and T2-weighted images in the subchondral bone adjacent or parallel to the articular surface associated with bone marrow oedema. Scintigraphy showed increased uptake in the femoral head. Insufficiency fractures of the femoral head are easily overlooked or confused with avascular necrosis and, when there is significant joint destruction, osteoarthritis. Unsuspected insufficiency fracture of the femoral head can lead to significant and rapid loss of bone stock in osteoporotic patients waiting for arthroplasty for osteoarthritis. Increased awareness of this condition will hopefully lead to earlier diagnosis and a successful outcome of conservative treatment. (orig.)

  17. Subchondral insufficiency fracture of the knee: a non-traumatic injury with prolonged recovery time.

    Science.gov (United States)

    Gourlay, Margaret L; Renner, Jordan B; Spang, Jeffrey T; Rubin, Janet E

    2015-06-08

    Subchondral insufficiency fractures are non-traumatic fractures that occur immediately below the cartilage of a joint. Although low bone density may be present concurrently, it is not the underlying cause of subchondral insufficiency fractures in the majority of patients. Patients with subchondral insufficiency fracture characteristically have unremarkable plain radiographs, while MRI examination may reveal extensive bone marrow oedema and subchondral bone collapse. This article presents a 51-year-old postmenopausal woman, a physician, who had subchondral insufficiency fractures of the knee associated with prolonged standing during clinical work. She was treated with partial weight bearing on crutches until 14 months after the injury, viscosupplementation at 4 months to treat osteoarthritis and teriparatide treatment to improve bone healing at 7 months. By 26 months after the injury, she tolerated independent walking with a fabric knee support but still experienced mild posterolateral knee pain and numbness on prolonged standing. 2015 BMJ Publishing Group Ltd.

  18. Mangiferin Reduces the Inhibition of Chondrogenic Differentiation by IL-1β in Mesenchymal Stem Cells from Subchondral Bone and Targets Multiple Aspects of the Smad and SOX9 Pathways

    Directory of Open Access Journals (Sweden)

    Jeong-Eun Huh

    2014-09-01

    Full Text Available Mangiferin is a natural immunomodulator found in plants including mango trees. The effects of mangiferin on chondrogenesis and cartilage repair have not yet been reported. This study was designed to determine the effect of mangiferin on chondrogenic differentiation in IL-1β-stimulated mesenchymal stem cells (MSCs from subchondral bone and to explore the mechanisms underlying these effects. MSCs were isolated from the subchondral bone of rabbit and treated with mangiferin alone and/or interleukin-1β (IL-1β. Mangiferin induced chondrogenic differentiation in MSCs by upregulating transforming growth factor (TGF-β, bone morphogenetic protein (BMP-2, and BMP-4 and several key markers of chondrogenesis, including sex-determining region Y–box (SRY-box containing gene 9 (SOX9, type 2α1 collagen (Col2α1, cartilage link protein, and aggrecan. In IL-1β-stimulated MSCs, mangiferin significantly reversed the production of TGF-β, BMP-2, BMP-4, SOX9, Col2α1, cartilage link protein, and aggrecan, as well as matrix metalloproteinase (MMP-1, MMP-13, and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS5. Mangiferin upregulated the phosphorylation of Smad 2, Smad 3, Smad 1/5/8, and SOX9 in IL-1β-stimulated MSCs. In the presence of mangiferin, SOX9 siRNA suppressed the activation of Smad 2, Smad 3, Smad 1/5/8, aggrecan, and Col2α1 expression. In conclusion, mangiferin exhibits both chondrogenic and chondroprotective effects on damaged MSCs and mediates these effects by targeting multiple aspects of the Smad and SOX9 signaling pathways.

  19. Small subchondral drill holes improve marrow stimulation of articular cartilage defects.

    Science.gov (United States)

    Eldracher, Mona; Orth, Patrick; Cucchiarini, Magali; Pape, Dietrich; Madry, Henning

    2014-11-01

    Subchondral drilling is an established marrow stimulation technique. Osteochondral repair is improved when the subchondral bone is perforated with small drill holes, reflecting the physiological subchondral trabecular distance. Controlled laboratory study. A rectangular full-thickness chondral defect was created in the trochlea of adult sheep (n = 13) and treated with 6 subchondral drillings of either 1.0 mm (reflective of the trabecular distance) or 1.8 mm in diameter. Osteochondral repair was assessed after 6 months in vivo by macroscopic, histological, and immunohistochemical analyses and by micro-computed tomography. The application of 1.0-mm subchondral drill holes led to significantly improved histological matrix staining, cellular morphological characteristics, subchondral bone reconstitution, and average total histological score as well as significantly higher immunoreactivity to type II collagen and reduced immunoreactivity to type I collagen in the repair tissue compared with 1.8-mm drill holes. Analysis of osteoarthritic changes in the cartilage adjacent to the defects revealed no significant differences between treatment groups. Restoration of the microstructure of the subchondral bone plate below the chondral defects was significantly improved after 1.0-mm compared to 1.8-mm drilling, as shown by higher bone volume and reduced thickening of the subchondral bone plate. Likewise, the microarchitecture of the drilled subarticular spongiosa was better restored after 1.0-mm drilling, indicated by significantly higher bone volume and more and thinner trabeculae. Moreover, the bone mineral density of the subchondral bone in 1.0-mm drill holes was similar to the adjacent subchondral bone, whereas it was significantly reduced in 1.8-mm drill holes. No significant correlations existed between cartilage and subchondral bone repair. Small subchondral drill holes that reflect the physiological trabecular distance improve osteochondral repair in a translational

  20. Chemical denudation of the soil

    Energy Technology Data Exchange (ETDEWEB)

    Arrhenius, O

    1952-01-01

    The chemical denudation plays a greater role in our climate than the mechanical erosion. The Swedish well waters contain 3-4 times more soluble salts than those rivers which are fed by them. The chemical denudation therefore must be much greater than formerly calculated. A map shows the salt concentration of the well waters of Sweden. The amount of nitrogen accumulated per annum in a district of central Sweden seems to amount to 3-6 kg n per har.

  1. Reviewing subchondral cartilage surgery: considerations for standardised and outcome predictable cartilage remodelling: a technical note.

    Science.gov (United States)

    Benthien, Jan P; Behrens, Peter

    2013-11-01

    The potential of subchondral mesenchymal stem cell stimulation (MSS) for cartilage repair has led to the widespread use of microfracture as a first line treatment for full thickness articular cartilage defects. Recent focus on the effects of subchondral bone during cartilage injury and repair has expanded the understanding of the strengths and limitations in MSS and opened new pathways for potential improvement. Comparative studies have shown that bone marrow access has positive implications for pluripotential cell recruitment, repair quality and quantity, i.e. deeper channels elicited better cartilage fill, more hyaline cartilage character with higher type II collagen content and lower type I collagen content compared to shallow marrow access. A subchondral needling procedure using standardised and thin subchondral perforations deep into the subarticular bone marrow making the MSS more consistent with the latest developments in subchondral cartilage remodelling is proposed. As this is a novel method clinical studies have been initiated to evaluate the procedure especially compared to microfracturing. However, the first case studies and follow-ups indicate that specific drills facilitate reaching the subchondral bone marrow while the needle size makes perforation of the subchondral bone easier and more predictable. Clinical results of the first group of patients seem to compare well to microfracturing. The authors suggest a new method for a standardised procedure using a new perforating device. Advances in MSS by subchondral bone marrow perforation are discussed. It remains to be determined by clinical studies how this method compares to microfracturing. The subchondral needling offers the surgeon and the investigator a method that facilitates comparison studies because of its defined depth of subchondral penetration and needle size.

  2. Cartilage Degeneration, Subchondral Mineral and Meniscal Mineral Densities in Hartley and Strain 13 Guinea Pigs

    Science.gov (United States)

    Sun, Yubo; Scannell, Brian P; Honeycutt, Patrick R; Mauerhan, David R; H, James Norton; Hanley Jr, Edward N

    2015-01-01

    Osteoarthritis is a joint disease involved in articular cartilage, subchondral bone, meniscus and synovial membrane. This study sought to examine cartilage degeneration, subchondral bone mineral density (BMD) and meniscal mineral density (MD) in male Hartley, female Hartley and female strain 13 guinea pigs to determine the association of cartilage degeneration with subchondral BMD and meniscal MD. Cartilage degeneration, subchondral BMD and meniscal MD in 12 months old guinea pigs were examined with histochemistry, X-ray densitometry and calcium analysis. We found that male Hartley guinea pigs had more severe cartilage degeneration, subchondral BMD and meniscal MD than female Hartley guinea pigs, but not female strain 13 guinea pigs. Female strain 13 guinea pigs had more severe cartilage degeneration and higher subchondral BMD, but not meniscal MD, than female Hartley guinea pigs. These findings indicate that higher subchondral BMD, not meniscal MD, is associated with more severe cartilage degeneration in the guinea pigs and suggest that abnormal subchondral BMD may be a therapeutic target for OA treatment. These findings also indicate that the pathogenesis of OA in the male guinea pigs and female guinea pigs are different. Female strain 13 guinea pig may be used to study female gender-specific pathogenesis of OA. PMID:26401159

  3. Imaging of acute injuries of the articular surfaces (chondral, osteochondral and subchondral fractures)

    Energy Technology Data Exchange (ETDEWEB)

    Bohndorf, K. [Department of Radiology, Zentralklinikum Augsburg (Germany)

    1999-10-01

    Fractures involving the articulating surfaces of bone are a common cause of chronic disability after joint injury. Acute fractures of the articular surface typically run parallel to the surface and are confined to the cartilage and/or the immediate subchondral cancellous bone. They should be distinguished from vertical or oblique bone fractures with intra-articular extension. This article reviews the mechanism of acute articular surface injuries, as well as their incidence, clinical presentation, radiologic appearance and treatment. A classification is presented based on direct inspection (arthroscopy) and imaging (especially MRI), emphasizing the distinction between lesions with intact (subchondral impaction and subchondral bone bruises) and disrupted (chondral, osteochondral lesions) cartilage. Hyaline cartilage, subchondral bone plate and subchondral cancellous bone are to be considered an anatomic unit. Subchondral articular surface lesions, osteochondral fractures and solely chondral fractures are different manifestations of impaction injuries that affect the articulating surface. Of the noninvasive imaging modalities, conventional radiography and MRI provide the most relevant information. The appropriate use of short tau inversion recovery, T1-weighted and T2-weighted (turbo) spin-echo as well as gradient-echo sequences, enables MRI to classify the various acute articular surface lesions with great accuracy and provides therapeutic guidance. (orig.)

  4. Imaging of acute injuries of the articular surfaces (chondral, osteochondral and subchondral fractures)

    International Nuclear Information System (INIS)

    Bohndorf, K.

    1999-01-01

    Fractures involving the articulating surfaces of bone are a common cause of chronic disability after joint injury. Acute fractures of the articular surface typically run parallel to the surface and are confined to the cartilage and/or the immediate subchondral cancellous bone. They should be distinguished from vertical or oblique bone fractures with intra-articular extension. This article reviews the mechanism of acute articular surface injuries, as well as their incidence, clinical presentation, radiologic appearance and treatment. A classification is presented based on direct inspection (arthroscopy) and imaging (especially MRI), emphasizing the distinction between lesions with intact (subchondral impaction and subchondral bone bruises) and disrupted (chondral, osteochondral lesions) cartilage. Hyaline cartilage, subchondral bone plate and subchondral cancellous bone are to be considered an anatomic unit. Subchondral articular surface lesions, osteochondral fractures and solely chondral fractures are different manifestations of impaction injuries that affect the articulating surface. Of the noninvasive imaging modalities, conventional radiography and MRI provide the most relevant information. The appropriate use of short tau inversion recovery, T1-weighted and T2-weighted (turbo) spin-echo as well as gradient-echo sequences, enables MRI to classify the various acute articular surface lesions with great accuracy and provides therapeutic guidance. (orig.)

  5. Case report: multifocal subchondral stress fractures of the femoral heads and tibial condyles in a young military recruit.

    Science.gov (United States)

    Yoon, Pil Whan; Yoo, Jeong Joon; Yoon, Kang Sup; Kim, Hee Joong

    2012-03-01

    Subchondral stress fractures of the femoral head may be either of the insufficiency-type with poor quality bone or the fatigue-type with normal quality bone but subject to high repetitive stresses. Unlike osteonecrosis, multiple site involvement rarely has been reported for subchondral stress fractures. We describe a case of multifocal subchondral stress fractures involving femoral heads and medial tibial condyles bilaterally within 2 weeks. A 27-year-old military recruit began having left knee pain after 2 weeks of basic training, without any injury. Subsequently, right knee, right hip, and left hip pain developed sequentially within 2 weeks. The diagnosis of multifocal subchondral stress fracture was confirmed by plain radiographs and MR images. Nonoperative treatment of the subchondral stress fractures of both medial tibial condyles and the left uncollapsed femoral head resulted in resolution of symptoms. The collapsed right femoral head was treated with a fibular strut allograft to restore congruity and healed without further collapse. There has been one case report in which an insufficiency-type subchondral stress fracture of the femoral head and medial femoral condyle occurred within a 2-year interval. Because the incidence of bilateral subchondral stress fractures of the femoral head is low and multifocal involvement has not been reported, multifocal subchondral stress fractures can be confused with multifocal osteonecrosis. Our case shows that subchondral stress fractures can occur in multiple sites almost simultaneously.

  6. Subchondral drilling for articular cartilage repair: a systematic review of translational research.

    Science.gov (United States)

    Gao, Liang; Goebel, Lars K H; Orth, Patrick; Cucchiarini, Magali; Madry, Henning

    2018-05-03

    Articular cartilage defects may initiate osteoarthritis. Subchondral drilling, a widely applied clinical technique to treat small cartilage defects, does not yield cartilage regeneration. Various translational studies aiming to improve the outcome of drilling have been performed, however, a robust systematic analysis of its translational evidence has been still lacking. Here, we performed a systematic review of the outcome of subchondral drilling for knee cartilage repair in translational animal models. A total of 12 relevant publications studying 198 animals were identified, detailed study characteristics were extracted, and methodological quality and risk of bias were analyzed. Subchondral drilling was superior to defects untreated or treated with abrasion arthroplasty for cartilage repair in multiple translational models. Considerable subchondral bone changes were observed, including subchondral bone cysts and intralesional osteophytes. Furthermore, extensive alterations of the subchondral bone microarchitecture appeared in a temporal pattern in small and large animal models, together with specific topographic aspects of repair. Moreover, variable technical aspects directly affected the outcomes of osteochondral repair. The data from this systematic review indicate that subchondral drilling yields improved short-term structural articular cartilage repair compared with spontaneous repair in multiple small and large animal models. These results have important implications for future investigations aimed at an enhanced translation into clinical settings for the treatment of cartilage defects, highlighting the importance of considering specific aspects of modifiable variables such as improvements in the design and reporting of preclinical studies, together with the need to better understand the underlying mechanisms of cartilage repair following subchondral drilling. © 2018. Published by The Company of Biologists Ltd.

  7. The study of subchondral lesions in osteoarthritis of the knee using magnetic resonance imaging

    International Nuclear Information System (INIS)

    Takagishi, Hiroshi

    2001-01-01

    In order to examine the significance of the signal abnormalities of subchondral bone in osteoarthritic knee with 0.5 T magnetic resonance imaging (MRI), especially in T2-low signal lesions which show a low signal intensity on both the T1- and T2-weighted images and T2-high signal lesions which show a low signal intensity on the T1-weighted image and a high signal intensity on the T2-weighted image, we examined 54 patients (representing 58 knees) with osteoarthritis (OA) of the knee on MRI as compared with the arthroscopic findings or operative findings and histologically evaluated them. In addition, in order to elucidate what becomes of those signal abnormalities in the subchondral bone after biomechanical treatment utilizing a high tibial osteotomy (HTO) which reduces the maldistributed load, we examined 30 patients (representing 34 knees) under HTO on MRI and compared these findings with the arthroscopic findings. The incidence of the presence of those signal abnormalities of subchondral bone on MRI tended to correlate with the severity of the articular cartilage damage, and also reflected the degree of damage to the articular cartilage well. In a histologically investigation, T2-high signal lesions showed granulation tissue with high vascularity, which seemed to be an active phase in OA. T2-low signal lesions of OA in a late stage showed subchondral sclerosis histologically. In addition, the signal changes of the subchondral bone on MRI seemed correlate with the changes in the load distribution in the knee joint because T2-high signal lesions before HTO were observed to either diminish or disappear after undergoing a successful osteotomy. The signal abnormalities of the subchondral bone on MRI on OA thus helped in determining the appropriate phase, therapeutic effects and prognosis of OA. (author)

  8. Theory of denudation tectonics and practice in prospecting. Pt.1

    International Nuclear Information System (INIS)

    Tong Hangshou

    1994-01-01

    The theory of denudation tectonics--earth science frontiers--upsurged in the 1980's of the century and a great mass fervor of its research has spread to the uranium geology. For the studying and applying the theory of denudation tectonics and on the invitation of the Editorial Department of 'Uranium Geology', this paper has been written and will be published in several issues with the following contents accordingly: (1) New progress in the research on denudation tectonics in China; (2) The evolution of denudation tectonics' concept and layer zoning of the Earth; (3) The fundamental implication of the denudation tectonics and relevant tectonic terminology; (4) Discussion on dynamics of the formation of denudation tectonics; (5) Definition and discrimination of denudation tectonics; (6) Research method of denudation tectonics; (7) Ore control theory of denudation tectonics and prospecting; (8) Outlook on the research of denudation tectonics

  9. Functional CT imaging: load-dependent visualization of the subchondral mineralization by means of CT osteoabsorptionmetry (CT-OAM)

    International Nuclear Information System (INIS)

    Linsenmaier, U.; Schlichtenhorst, K.; Pfeifer, K.J.; Reiser, M.; Kersting, S.; Putz, R.; Mueller-Gerbl, M.

    2003-01-01

    Purpose: Functional computed tomography for visualization and quantification of subchondral bone mineralization using CT osteoabsorptiometry (CT-OAM). Materials and Methods: Tarsometatarsal (TMT) and metatarsophalangeal (MTP) joints of 46 human hallux valgus (HV) specimens were examined (sagittal 1/1/1 mm) on a single slice CT scanner SCT (Somatom Plus 4, Siemens AG). Subchondral bone pixels were segmented and assigned to 10 density value groups (triangle 100 HU, range 200 - 1200 HU) the pixels using volume rendering technique (VRT). The data analysis considered the severity of HV as determined by the radiographically measured HV-angle (a.p. projection). Results: CT-OAM could generate reproducible densitograms of the distribution pattern of the subchondral bone density for all four joint surfaces (TMT and MTP joints). The bone density localization enables the assignment to different groups, showing a characteristic HV-angle-dependent distribution of the maximum bone mineralization of the load-dependent densitogram (p [de

  10. Subchondral stress fracture of femoral head in a healthy adult

    Directory of Open Access Journals (Sweden)

    Anand Ashish

    2010-01-01

    Full Text Available Subchondral fracture of the femoral head is an uncommon entity and usually occurs as an insufficiency fracture associated with poor bone quality or as a fatigue fracture in young military recruits. This condition should be considered in the differential diagnosis of acute hip pain in young patients along with transient osteoporosis and avascular necrosis of the hip. We report a case of acute onset hip pain in an asymptomatic healthy adult in which the diagnosis was made by magnetic resonance imaging and the patient responded well to conservative treatment.

  11. Fat-suppressed T2-weighted MRI appearance of subchondral insufficiency fracture of the femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Sonoda, Kazuhiko; Yamamoto, Takuaki; Motomura, Goro; Karasuyama, Kazuyuki; Kubo, Yusuke; Iwamoto, Yukihide [Kyushu University, Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan)

    2016-11-15

    Our aims were to investigate the imaging appearance of subchondral insufficiency fracture (SIF) of the femoral head based on fat-suppressed T2-weighted MRI, and evaluate its correlation with the clinical outcomes following conservative treatment. We retrospectively evaluated 40 hips in 37 patients with SIF of the femoral head (12 males and 25 females; mean age 55.8 years, range 22-78 years). MRI examinations were performed within 3 months after the onset of hip pain. Using fat-suppressed T2-weighted imaging, we evaluated the hips for the intensity of the subchondral bone (corresponding to the area superior to the low intensity band on T1-weighted images) as well as bone marrow edema, joint effusion, and presence of the band lesion. We then correlated the intensity of the subchondral bone with clinical outcomes. The hips were classified into three types based on subchondral intensity on fat-suppressed T2-weighted images: type 1 (21 hips) showed high intensity, type 2 (eight hips) showed heterogeneous intensity, and type 3 (11 hips) showed low intensity. The mean period between pain onset and MRI examination was significantly longer for type 2 hips than for type 1. Healing rates were 86 % for type 1, 75 % for type 2, and 18 % for type 3. SIF cases were classified into three types based on subchondral intensity on fat-suppressed T2-weighted imaging performed within 3 months after pain onset. Type 3 SIF tended to be intractable to conservative treatment compared to type 1 and type 2. (orig.)

  12. Bone structural changes in osteoarthritis as a result of mechanoregulated bone adaptation: a modeling approach

    NARCIS (Netherlands)

    Cox, L.G.E.; Rietbergen, van B.; Donkelaar, van C.C.; Ito, K.

    2011-01-01

    Objective There are strong indications that subchondral bone may play an important role in osteoarthritis (OA), making it an interesting target for medical therapies. The subchondral bone structure changes markedly during OA, and it has long been assumed that this occurs secondary to cartilage

  13. Contrast-enhanced MRI of subchondral cysts in patients with or at risk for knee osteoarthritis: The MOST study

    International Nuclear Information System (INIS)

    Crema, M.D.; Roemer, F.W.; Marra, M.D.; Niu, J.; Lynch, J.A.; Felson, D.T.; Guermazi, A.

    2010-01-01

    Objective: The aim of the study was (1) to evaluate contrast enhancement patterns of subchondral cysts on magnetic resonance imaging and (2) to discuss possible radiological explanations of cyst enhancement based on existing theories of subchondral cyst formation in osteoarthritis. Materials and methods: The Multicenter Osteoarthritis Study (MOST) is a NIH-funded longitudinal observational study for individuals who have or are at high risk for knee osteoarthritis. All subjects with available non-enhanced and contrast-enhanced MRI were included. The tibiofemoral and patellofemoral joints were divided in 14 subregions. The presence and size of subchondral cysts and bone marrow edema-like lesions (BMLs) were scored semiquantitatively in each subregion on non-contrast-enhanced MRI from 0 to 3. Enhancement of subchondral cysts was evaluated on contrast-enhanced MRI as grade 0 (absent), grade 1 (partial enhancement), or grade 2 (full enhancement). The adjacent articular cartilage was scored in each subregion on non-enhanced MRI as grade 0 (intact), grade 1 (partial thickness loss), or grade 2 (full thickness loss). Results: Four hundred knees were included (1 knee per person, 5600 subregions). Subchondral cysts were detected in 260 subregions (4.6%). After intravenous contrast administration, 245 cysts (94.2%) showed full enhancement, 12 (4.6%) showed partial enhancement and 3 (1.2%) showed no enhancement. Enhancing BMLs were found in 237 (91.2%) subregions containing cysts, which were located adjacent or in the middle of BMLs. In 121 subregions (46.5%) having cysts, no adjacent full thickness cartilage loss was detected. Conclusion: Most subchondral cysts demonstrated full or partial contrast enhancement, and were located adjacent or in the midst of enhancing BMLs. As pure cystic lesions are not expected to enhance on MRI, the term 'subchondral cyst-like bone marrow lesion' might be appropriate to describe these lesions.

  14. Contrast-enhanced MRI of subchondral cysts in patients with or at risk for knee osteoarthritis: The MOST study

    Energy Technology Data Exchange (ETDEWEB)

    Crema, M.D., E-mail: michelcrema@gmail.co [Department of Radiology, Boston University School of Medicine, 820 Harrison Ave, FGH Building, 3rd Floor, Boston, MA 02118 (United States); Roemer, F.W., E-mail: frank.roemer@klinikum-augsburg.d [Department of Radiology, Boston University School of Medicine, 820 Harrison Ave, FGH Building, 3rd Floor, Boston, MA 02118 (United States); Department of Radiology, Klinikum Augsburg, Stenglinstrasse 2, Augsburg 86156 (Germany); Marra, M.D., E-mail: monicadiasmarra@gmail.co [Department of Radiology, Boston University School of Medicine, 820 Harrison Ave, FGH Building, 3rd Floor, Boston, MA 02118 (United States); Niu, J., E-mail: niujp@bu.ed [Clinical Epidemiology Research and Training Unit, Boston University School of Medicine, 650 Albany Street, X Building, Suite 200, Boston, MA 02118 (United States); Lynch, J.A., E-mail: jlynch@psg.ucsf.ed [Department of Epidemiology and Biostatistics, University of California at San Francisco, 185 Berry Street, Lobby 5, Suite 5700, San Francisco, CA 94107 (United States); Felson, D.T., E-mail: dfelson@bu.ed [Clinical Epidemiology Research and Training Unit, Boston University School of Medicine, 650 Albany Street, X Building, Suite 200, Boston, MA 02118 (United States); Guermazi, A., E-mail: ali.guermazi@bmc.or [Department of Radiology, Boston University School of Medicine, 820 Harrison Ave, FGH Building, 3rd Floor, Boston, MA 02118 (United States)

    2010-07-15

    Objective: The aim of the study was (1) to evaluate contrast enhancement patterns of subchondral cysts on magnetic resonance imaging and (2) to discuss possible radiological explanations of cyst enhancement based on existing theories of subchondral cyst formation in osteoarthritis. Materials and methods: The Multicenter Osteoarthritis Study (MOST) is a NIH-funded longitudinal observational study for individuals who have or are at high risk for knee osteoarthritis. All subjects with available non-enhanced and contrast-enhanced MRI were included. The tibiofemoral and patellofemoral joints were divided in 14 subregions. The presence and size of subchondral cysts and bone marrow edema-like lesions (BMLs) were scored semiquantitatively in each subregion on non-contrast-enhanced MRI from 0 to 3. Enhancement of subchondral cysts was evaluated on contrast-enhanced MRI as grade 0 (absent), grade 1 (partial enhancement), or grade 2 (full enhancement). The adjacent articular cartilage was scored in each subregion on non-enhanced MRI as grade 0 (intact), grade 1 (partial thickness loss), or grade 2 (full thickness loss). Results: Four hundred knees were included (1 knee per person, 5600 subregions). Subchondral cysts were detected in 260 subregions (4.6%). After intravenous contrast administration, 245 cysts (94.2%) showed full enhancement, 12 (4.6%) showed partial enhancement and 3 (1.2%) showed no enhancement. Enhancing BMLs were found in 237 (91.2%) subregions containing cysts, which were located adjacent or in the middle of BMLs. In 121 subregions (46.5%) having cysts, no adjacent full thickness cartilage loss was detected. Conclusion: Most subchondral cysts demonstrated full or partial contrast enhancement, and were located adjacent or in the midst of enhancing BMLs. As pure cystic lesions are not expected to enhance on MRI, the term 'subchondral cyst-like bone marrow lesion' might be appropriate to describe these lesions.

  15. Denudation rates and tectonic geomorphology of the Spanish Betic Cordillera

    Science.gov (United States)

    Bellin, N.; Vanacker, V.; Kubik, P. W.

    2014-03-01

    The tectonic control on landscape morphology and long-term denudation is largely documented for settings with high uplift rates. Relatively little is known about the rates of geomorphic response in areas of low tectonic uplift. Here, we evaluate spatial variations in denudation of the Spanish Betic Cordillera based on cosmogenic 10Be-derived denudation rates. Denudation rates are compared to published data on rock uplift and exhumation of the Betic Cordillera to evaluate steady-state topography. The spatial patterns of catchment-wide denudation rates (n=20) are then analysed together with topographic metrics of hillslope and channel morphology. Catchments draining the Betic ranges have relatively low denudation rates (64±54 mm kyr), but also show large variation as they range from 14 to 246 mm kyr-1. Catchment-wide denudation is linearly proportional to the mean hillslope gradient and local relief. Despite large spatial variation in denudation, the magnitude and spatial pattern of denudation rates are generally consistent with longer-term local uplift rates derived from elevated marine deposits, fission-track measurements and vertical fault slip rates. This might be indicative of a steady-state topography where rock uplift is balanced by denudation.

  16. Subchondral synovial cysts (intra-osseous ganglion)

    International Nuclear Information System (INIS)

    Graf, L.; Freyschmidt, J.

    1988-01-01

    Twelve cases of subchondral synovial cysts (intra-osseous ganglion) have been seen and their clinical features, radiological findings and differential diagnosis are described. The lesion is a benign cystic tumour-like mass in the subchondral portion of a synovial joint. Our findings in respect of age, sex and localisation are compared with those of other authors. The aetiology and pathogenesis of the lesion is not completely understood. There is an increased incidence in middle life and joints with high dynamic and static stress are favoured, particularly in the lower extremities. Chronic stress or microtrauma, causing damage to the involved joint, therefore appears to be a plausible explanation. (orig.) [de

  17. Imaging and histological features of central subchondral osteophytes in racehorses with metacarpophalangeal joint osteoarthritis.

    Science.gov (United States)

    Olive, J; D'Anjou, M A; Girard, C; Laverty, S; Theoret, C L

    2009-12-01

    Marginal osteophytes represent a well known component of osteoarthritis in man and animals. Conversely, central subchondral osteophytes (COs), which are commonly present in human knees with osteoarthritis, have not been reported in horses. To describe and compare computed radiography (CR), single-slice computed tomography (CT), 1.5 Tesla magnetic resonance imaging (MRI), and histological features of COs in equine metacarpophalangeal joints with macroscopic evidence of naturally-occurring osteoarthritis. MRI sequences (sagittal spoiled gradient recalled echo [SPGR] with fat saturation, sagittal T2-weighted fast spin echo with fat saturation [T2-FS], dorsal and transverse T1-weighted gradient-recalled echo [GRE], and sagittal T2*-weighted gradient echo with fast imaging employing steady state acquisition [FIESTA]), as well as transverse and reformatted sagittal CTI and 4 computed radiographic (CR) views of 20 paired metacarpophalangeal joints were acquired ex vivo. Following macroscopic evaluation, samples were harvested in predetermined sites of the metacarpal condyle for subsequent histology. The prevalence and detection level of COs was determined for each imaging modality. Abnormalities consistent with COs were clearly depicted on MRI, using the SPGR sequence, in 7/20 (35%) joints. They were identified as a focal hypointense protuberance from the subchondral plate into the cartilage, at the palmarodistal aspect (n=7) and/or at the very dorsal aspect (n=2) of the metacarpal condyle. COs were visible but less obvious in 5 of the 7 joints using FIESTA and reformatted sagittal CT, and were not identifiable on T2-FS, T1-GRE or CR. Microscopically, they consisted of dense bone protruding into the calcified cartilage and disrupting the tidemarks, and they were consistently associated with overlying cartilage defects. Subchondral osteophytes are a feature of osteoarthritis of equine metacarpophalangeal joints and they may be diagnosed using 1.5 Tesla MRI and CT. Central

  18. Long-term evolution of denudational escarpments in southeastern Brazil

    Science.gov (United States)

    Cherem, Luis Felipe Soares; Varajão, Cesar Augusto C.; Braucher, Regis; Bourlés, Didier; Salgado, André Augusto R.; Varajão, Angélica C.

    2012-11-01

    Topographic relief in southeastern Brazil consists of a sequence of stepped surfaces that formed after the fragmentation of Gondwana during the Cretaceous, Tertiary and Quaternary tectonic pulses. This region is drained by four major rivers within four major river basins, with interfluves that contain denudational escarpments, fault escarpments and mountain ranges. This study presents an analysis of the long-term evolution of two denudational escarpments, the Cristiano Otoni and the São Geraldo steps, which divide the river basins of the São Francisco, Doce and Paraíba do Sul rivers in southeastern Brazil. Denudation rates were obtained through the measurement of mean concentrations of in situ produced cosmogenic 10Be in sand-sized fluvial quartz sediments collected from granitic terrains. The rates were calculated and compared with one another and correlated to the basin-scale mean relief, slope, area, and stream power. The mean denudation rates of the Cristiano Otoni and São Geraldo highlands are 8.77 (± 2.78) m My- 1 and 15.68 (± 4.53) m My- 1, respectively. The mean denudation rates of the Cristiano Otoni and São Geraldo escarpments are 17.50 (± 2.71) m My- 1 and 21.22 (± 4.24) m My- 1, respectively. The denudation rates of the catchments of highlands that drain toward the escarpments are similar to those of their respective highlands. The results demonstrate that relief and slope have similar positive control on the denudation rates for all of the samples despite their different geomorphic context and history of landscape evolution. The São Francisco River Basin is losing area to the Doce River Basin, which, in turn, is losing area to the Paraíba do Sul River Basin.

  19. Distal clavicular osteolysis: MR evidence for subchondral fracture

    Energy Technology Data Exchange (ETDEWEB)

    Kassarjian, Ara; Palmer, William E. [Massachusetts General Hospital, Department of Radiology, Division of Musculoskeletal Radiology, Yawkey Center, Boston, MA (United States); Llopis, Eva [Hospital de la Ribera, Department of Radiology, Valencia (Spain)

    2007-01-15

    To investigate the association between distal clavicular osteolysis and subchondral fractures of the distal clavicle at MRI. This study was approved by the hospital human research committee, which waived the need for informed consent. Three radiologists retrospectively analyzed 36 shoulder MR examinations in 36 patients with imaging findings of distal clavicular osteolysis. The presence of a subchondral fracture of the distal clavicle, abnormalities of the acromioclavicular joint, rotator cuff tears and labral tears were assessed by MRI. These cases were then compared with 36 age-matched controls. At MRI, 31 of 36 patients (86%) had a subchondral line within the distal clavicular edema, consistent with a subchondral fracture. Of the 36 patients, 32 (89%) had fluid in the acromioclavicular joint, while 27 of 36 patients (75%) had cysts or erosions in the distal clavicle. There were 13 patients (36%) with associated labral tears, while eight patients (22%) had partial-thickness rotator cuff tears. In the control group one of 36 (3%) had a subchondral line (P<0.05), while ten of 36 (28%) had rotator cuff tears and 13 of 36 (36%) had labral tears. These latter two were not statistically significant between the groups. A distal clavicular subchondral fracture is a common finding in patients with imaging evidence of distal clavicular osteolysis. These subchondral fractures may be responsible for the propensity of findings occurring on the clavicular side of the acromioclavicular joint. (orig.)

  20. Distal clavicular osteolysis: MR evidence for subchondral fracture

    International Nuclear Information System (INIS)

    Kassarjian, Ara; Palmer, William E.; Llopis, Eva

    2007-01-01

    To investigate the association between distal clavicular osteolysis and subchondral fractures of the distal clavicle at MRI. This study was approved by the hospital human research committee, which waived the need for informed consent. Three radiologists retrospectively analyzed 36 shoulder MR examinations in 36 patients with imaging findings of distal clavicular osteolysis. The presence of a subchondral fracture of the distal clavicle, abnormalities of the acromioclavicular joint, rotator cuff tears and labral tears were assessed by MRI. These cases were then compared with 36 age-matched controls. At MRI, 31 of 36 patients (86%) had a subchondral line within the distal clavicular edema, consistent with a subchondral fracture. Of the 36 patients, 32 (89%) had fluid in the acromioclavicular joint, while 27 of 36 patients (75%) had cysts or erosions in the distal clavicle. There were 13 patients (36%) with associated labral tears, while eight patients (22%) had partial-thickness rotator cuff tears. In the control group one of 36 (3%) had a subchondral line (P<0.05), while ten of 36 (28%) had rotator cuff tears and 13 of 36 (36%) had labral tears. These latter two were not statistically significant between the groups. A distal clavicular subchondral fracture is a common finding in patients with imaging evidence of distal clavicular osteolysis. These subchondral fractures may be responsible for the propensity of findings occurring on the clavicular side of the acromioclavicular joint. (orig.)

  1. How fast is the denudation of the Taiwan Mountains? (Invited)

    Science.gov (United States)

    Siame, L. L.; Derrieux, F.; KANG, C.; Bourles, D. L.; Braucher, R.; Léanni, L.; Chen, R.; Lee, J.; Chu, H.; Chang, C.; Byrne, T. B.

    2013-12-01

    Orogenic settings are particularly well suited to study and quantify the coupling relations between tectonics, topography, climate and erosion since they record tectonic evolution along convergent margins and the connection between deep and surface processes. However, the interaction of deep and shallow processes is still poorly understood and the role they play in the exhumation of rocks, the structural and kinematic evolution of orogenic wedges, and the relation between tectonics and climate-dependent surface processes are still debated. Therefore, quantification of denudation rates in a wide range of climatic and tectonic settings, as well as at various time and space scales, is a critical step in calibrating and validating landscape evolution models. In this study, we focus on the mountains of the arc-continent collision in Taiwan, which serve as one of the best examples in the world to understand and study mountain building processes. We investigate the pattern and magnitude of denudation rates at the scale of the orogenic system, deriving denudation rates from in situ-produced cosmogenic nuclide 10Be concentrations measured in (1) river-borne quartz minerals sampled at major watersheds outlets, and (2) bedrock outcrops along ridge crests and at summits located along the major drainage divide of the belt. We determined a denudation pattern showing a clear discrepancy between the western (1.7×0.2 mm/yr) and eastern (4.1×0.5 mm/yr) sides of the range. Conversely, bedrock denudation determined along ridge crests, summits and flat surfaces preserved at high elevations are characterized by significantly lower denudation rates on the order of 0.24×0.03 mm/yr. Altogether, the cosmogenic-derived denudation pattern at the orogen-scale reflects fundamental mountain building processes from frontal accretion in the Western Foothills to basal accretion and fast exhumation in the Central Range. Applied to the whole orogen, such field-based approach thus provides

  2. Uncommon observation of bifocal giant subchondral cysts in the hip. Diagnostic role of CT arthrography and MRI, with pathological correlation

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Espino, Pauline; Cauter, Maite van; Gossing, Louis [Universite Catholique de Louvain, Department of Orthopedic Surgery, Institut de Recherche Experimentale et Clinique (IREC), Cliniques Universitaires Saint Luc, Brussels (Belgium); Galant, Christine C. [Universite Catholique de Louvain, Department of Pathology, Institut de Recherche Experimentale et Clinique (IREC), Cliniques Universitaires Saint Luc, Brussels (Belgium); Acid, Souad; Lecouvet, Frederic E. [Universite Catholique de Louvain, Department of Radiology, Institut de Recherche Experimentale et Clinique (IREC), Cliniques Universitaires Saint Luc, Brussels (Belgium)

    2018-04-15

    Subchondral cysts (or geodes) are common in osteoarthritis (OA), usually in association with other typical signs, i.e., joint space narrowing, subchondral bone sclerosis, and osteophytosis. However, large lesions without the typical signs of OA or lesions located outside the weight-bearing areas are unusual and may be confused for other conditions, in particular, those of tumoral origin. We report the findings in a 48-year-old man who had been complaining of left buttock pain for 3 years, getting worse over the last year, and an evolutive limited range of motion of the hip. The pain was increased by weight-bearing and was not relieved by nonsteroidal anti-inflammatory drugs. Radiographs and CT showed a large multilocular lytic lesion within the femoral head and a large lytic lesion in the left ilio-ischiatic ramus, raising the question of bifocal tumoral involvement. On MRI, the lesions had low signal intensity on T1- and high signal intensity on T2-weighted MR images, with subtle peripheral enhancement on post-contrast T1-weighted images. CT arthrography, by demonstrating a communication between the femoral head and ischiatic cysts and the joint space allowed us to definitively rule out malignant conditions and to make the diagnosis of subchondral bone cysts. Total hip arthroplasty was performed. Pathological analysis of the resected femoral head and of material obtained at curettage of the ischiatic lesion confirmed the diagnosis of degenerative geodes. This case illustrates an atypical bifocal location of giant subchondral cysts in the hip joint mimicking lytic tumors, in the absence of osteoarthritis or rheumatoid arthritis, and highlights the role of CT arthrography in identifying this condition. (orig.)

  3. Subchondral mesenchymal stem cells from osteoarthritic knees display high osteogenic differentiation capacity through microRNA-29a regulation of HDAC4.

    Science.gov (United States)

    Lian, Wei-Shiung; Wu, Ren-Wen; Lee, Mel S; Chen, Yu-Shan; Sun, Yi-Chih; Wu, Shing-Long; Ke, Huei-Jing; Ko, Jih-Yang; Wang, Feng-Sheng

    2017-12-01

    Subchondral bone deterioration and osteophyte formation attributable to excessive mineralization are prominent features of end-stage knee osteoarthritis (OA). The cellular events underlying subchondral integrity diminishment remained elusive. This study was undertaken to characterize subchondral mesenchymal stem cells (SMSCs) isolated from patients with end-stage knee OA who required total knee arthroplasty. The SMSCs expressed surface antigens CD29, CD44, CD73, CD90, CD105, and CD166 and lacked CD31, CD45, and MHCII expression. The cell cultures exhibited higher proliferation and greater osteogenesis and chondrogenesis potencies, whereas their population-doubling time and adipogenic lineage commitment were lower than those of bone marrow MSCs (BMMSCs). They also displayed higher expressions of embryonic stem cell marker OCT3/4 and osteogenic factors Wnt3a, β-catenin, and microRNA-29a (miR-29a), concomitant with lower expressions of joint-deleterious factors HDAC4, TGF-β1, IL-1β, TNF-α, and MMP3, in comparison with those of BMMSCs. Knockdown of miR-29a lowered Wnt3a expression and osteogenic differentiation of the SMSCs through elevating HDAC4 translation, which directly regulated the 3'-untranslated region of HDAC4. Likewise, transgenic mice that overexpressed miR-29a in osteoblasts exhibited a high bone mass in the subchondral region. SMSCs in the transgenic mice showed a higher osteogenic differentiation and lower HDAC4 signaling than those in wild-type mice. Taken together, high osteogenesis potency existed in the SMSCs in the osteoarthritic knee. The miR-29a modulation of HDAC4 and Wnt3a signaling was attributable to the increase in osteogenesis. This study shed an emerging light on the characteristics of SMSCs and highlighted the contribution of SMSCs in the exacerbation of subchondral integrity in end-stage knee OA. Subchondral MSCs (SMSCs) from OA knee expressed embryonic stem cell marker Oct3/4. The SMSCs showed high proliferation and osteogenic and

  4. Effect of a Rapidly Degrading Presolidified 10 kDa Chitosan/Blood Implant and Subchondral Marrow Stimulation Surgical Approach on Cartilage Resurfacing in a Sheep Model

    Science.gov (United States)

    Bell, Angela D.; Hurtig, Mark B.; Quenneville, Eric; Rivard, Georges-Étienne; Hoemann, Caroline D.

    2016-01-01

    Objective This study tested the hypothesis that presolidified chitosan-blood implants are retained in subchondral bone channels perforated in critical-size sheep cartilage defects, and promote bone repair and hyaline-like cartilage resurfacing versus blood implant. Design Cartilage defects (10 × 10 mm) with 3 bone channels (1 drill, 2 Jamshidi biopsy, 2 mm diameter), and 6 small microfracture holes were created bilaterally in n = 11 sheep knee medial condyles. In one knee, 10 kDa chitosan–NaCl/blood implant (presolidified using recombinant factor VIIa or tissue factor), was inserted into each drill and Jamshidi hole. Contralateral knee defects received presolidified whole blood clot. Repair tissues were assessed histologically, biochemically, biomechanically, and by micro–computed tomography after 1 day (n = 1) and 6 months (n = 10). Results Day 1 defects showed a 60% loss of subchondral bone plate volume fraction along with extensive subchondral hematoma. Chitosan implant was resident at day 1, but had no effect on any subsequent repair parameter compared with blood implant controls. At 6 months, bone defects exhibited remodeling and hypomineralized bone repair and were partly resurfaced with tissues containing collagen type II and scant collagen type I, 2-fold lower glycosaminoglycan and fibril modulus, and 4.5-fold higher permeability compared with intact cartilage. Microdrill holes elicited higher histological ICRS-II overall assessment scores than Jamshidi holes (50% vs. 30%, P = 0.041). Jamshidi biopsy holes provoked sporadic osteonecrosis in n = 3 debrided condyles. Conclusions Ten kilodalton chitosan was insufficient to improve repair. Microdrilling is a feasible subchondral marrow stimulation surgical approach with the potential to elicit poroelastic tissues with at least half the compressive modulus as intact articular cartilage. PMID:28934884

  5. Effect of a Rapidly Degrading Presolidified 10 kDa Chitosan/Blood Implant and Subchondral Marrow Stimulation Surgical Approach on Cartilage Resurfacing in a Sheep Model.

    Science.gov (United States)

    Bell, Angela D; Hurtig, Mark B; Quenneville, Eric; Rivard, Georges-Étienne; Hoemann, Caroline D

    2017-10-01

    Objective This study tested the hypothesis that presolidified chitosan-blood implants are retained in subchondral bone channels perforated in critical-size sheep cartilage defects, and promote bone repair and hyaline-like cartilage resurfacing versus blood implant. Design Cartilage defects (10 × 10 mm) with 3 bone channels (1 drill, 2 Jamshidi biopsy, 2 mm diameter), and 6 small microfracture holes were created bilaterally in n = 11 sheep knee medial condyles. In one knee, 10 kDa chitosan-NaCl/blood implant (presolidified using recombinant factor VIIa or tissue factor), was inserted into each drill and Jamshidi hole. Contralateral knee defects received presolidified whole blood clot. Repair tissues were assessed histologically, biochemically, biomechanically, and by micro-computed tomography after 1 day ( n = 1) and 6 months ( n = 10). Results Day 1 defects showed a 60% loss of subchondral bone plate volume fraction along with extensive subchondral hematoma. Chitosan implant was resident at day 1, but had no effect on any subsequent repair parameter compared with blood implant controls. At 6 months, bone defects exhibited remodeling and hypomineralized bone repair and were partly resurfaced with tissues containing collagen type II and scant collagen type I, 2-fold lower glycosaminoglycan and fibril modulus, and 4.5-fold higher permeability compared with intact cartilage. Microdrill holes elicited higher histological ICRS-II overall assessment scores than Jamshidi holes (50% vs. 30%, P = 0.041). Jamshidi biopsy holes provoked sporadic osteonecrosis in n = 3 debrided condyles. Conclusions Ten kilodalton chitosan was insufficient to improve repair. Microdrilling is a feasible subchondral marrow stimulation surgical approach with the potential to elicit poroelastic tissues with at least half the compressive modulus as intact articular cartilage.

  6. Magnetic resonance imaging of osteophytic, chondral, and subchondral structures in a surgically-induced osteoarthritis rabbit model.

    Directory of Open Access Journals (Sweden)

    Lang Jia

    Full Text Available OBJECTIVE: This study aimed to assess changes in osteophytic, chondral, and subchondral structures in a surgically-induced osteoarthritis (OA rabbit model in order to correlate MRI findings with the macroscopic progress of OA and to define the timepoint for disease status in this OA model. METHODS: The OA model was constructed by surgery in thirty rabbits with ten normal rabbits serving as controls (baseline. High-resolution three-dimensional MRI using a 1.5-T coil was performed at baseline, two, four, and eight weeks post-surgery. MRIs of cartilage lesions, subchondral bone lesions, and osteophyte formations were independently assessed by two blinded radiologists. Ten rabbits were sacrificed at baseline, two, four, and eight weeks post-surgery, and macroscopic evaluation was independently performed by two blinded orthopedic surgeons. RESULTS: The signal intensities and morphologies of chondral and subchondral structures by MRI accurately reflected the degree of OA. Cartilage defects progressed from a grade of 0.05-0.15 to 1.15-1.30 to 1.90-1.97 to 3.00-3.35 at each successive time point, respectively (p<0.05. Subchondral bone lesions progressed from a grade of 0.00 to 0.78-0.90 to 1.27-1.58 to 1.95-2.23 at each successive time point, respectively (p = 0.000. Osteophytes progressed from a size (mm of 0.00 to 0.87-1.06 to 1.24-1.87 to 2.21-3.21 at each successive time point, respectively (p = 0.000. CONCLUSIONS: Serial observations revealed that MRI can accurately detect the progression of cartilage lesions and subchondral bone edema over an eight-week period but may not be accurate in detecting osteophyte sizes. Week four post-surgery was considered the timepoint between OA-negative and OA-positive status in this OA model. The combination of this OA model with MRI evaluation should provide a promising tool for the pre-clinical evaluation of new disease-modifying osteoarthritis drugs.

  7. Magnetic resonance imaging of osteophytic, chondral, and subchondral structures in a surgically-induced osteoarthritis rabbit model.

    Science.gov (United States)

    Jia, Lang; Chen, Jinyun; Wang, Yan; Liu, Yingjiang; Zhang, Yu; Chen, Wenzhi

    2014-01-01

    This study aimed to assess changes in osteophytic, chondral, and subchondral structures in a surgically-induced osteoarthritis (OA) rabbit model in order to correlate MRI findings with the macroscopic progress of OA and to define the timepoint for disease status in this OA model. The OA model was constructed by surgery in thirty rabbits with ten normal rabbits serving as controls (baseline). High-resolution three-dimensional MRI using a 1.5-T coil was performed at baseline, two, four, and eight weeks post-surgery. MRIs of cartilage lesions, subchondral bone lesions, and osteophyte formations were independently assessed by two blinded radiologists. Ten rabbits were sacrificed at baseline, two, four, and eight weeks post-surgery, and macroscopic evaluation was independently performed by two blinded orthopedic surgeons. The signal intensities and morphologies of chondral and subchondral structures by MRI accurately reflected the degree of OA. Cartilage defects progressed from a grade of 0.05-0.15 to 1.15-1.30 to 1.90-1.97 to 3.00-3.35 at each successive time point, respectively (pSubchondral bone lesions progressed from a grade of 0.00 to 0.78-0.90 to 1.27-1.58 to 1.95-2.23 at each successive time point, respectively (p = 0.000). Osteophytes progressed from a size (mm) of 0.00 to 0.87-1.06 to 1.24-1.87 to 2.21-3.21 at each successive time point, respectively (p = 0.000). Serial observations revealed that MRI can accurately detect the progression of cartilage lesions and subchondral bone edema over an eight-week period but may not be accurate in detecting osteophyte sizes. Week four post-surgery was considered the timepoint between OA-negative and OA-positive status in this OA model. The combination of this OA model with MRI evaluation should provide a promising tool for the pre-clinical evaluation of new disease-modifying osteoarthritis drugs.

  8. Bilateral rapidly destructive arthrosis of the hip joint resulting from subchondral fracture with superimposed secondary osteonecrosis

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Takuaki; Iwamoto, Yukihide [Kyushu University, Department of Orthopaedic Surgery, Fukuoka (Japan); Schneider, Robert [Hospital for Special Surgery, Department of Radiology, New York (United States); Bullough, Peter G. [Hospital for Special Surgery, Department of Laboratory Medicine, New York, NY (United States)

    2010-02-15

    A 57-year-old woman suffered rapid destruction of both hip joints over a 10 months period. At the first visit, her radiographs demonstrated slight joint space narrowing and acetabular cyst formation in both hips. Five months later, joint space narrowing had further progressed, and intra-articular injection of steroid was given in both hips. However, the hip pain gradually became worse. Five months later, both joint spaces had totally disappeared and both femoral heads had undergone massive collapse. At gross examination, both resected femoral heads showed extensive opaque yellow areas consistent with osteonecrosis. Microscopic examination of these areas revealed evidence of both extensive fracture and callus formation, as well as necrosis throughout, indicating that the osteonecrosis observed in this case was a secondary phenomenon superimposed on pre-existing osteoarthritis and subchondral fracture. There were many pseudogranulomatous lesions in the marrow space and necrotic area, where tiny fragments of bone and articular cartilage, surrounded by histiocytes and giant cells, were embedded, such as are typically seen in rapidly destructive arthrosis. No radiologic or morphologic evidence of primary osteonecrosis was noted. This case indicates that at least some cases of rapidly destructive arthritis are the result of subchondral fracture with superimposed secondary osteonecrosis. (orig.)

  9. Bilateral rapidly destructive arthrosis of the hip joint resulting from subchondral fracture with superimposed secondary osteonecrosis

    International Nuclear Information System (INIS)

    Yamamoto, Takuaki; Iwamoto, Yukihide; Schneider, Robert; Bullough, Peter G.

    2010-01-01

    A 57-year-old woman suffered rapid destruction of both hip joints over a 10 months period. At the first visit, her radiographs demonstrated slight joint space narrowing and acetabular cyst formation in both hips. Five months later, joint space narrowing had further progressed, and intra-articular injection of steroid was given in both hips. However, the hip pain gradually became worse. Five months later, both joint spaces had totally disappeared and both femoral heads had undergone massive collapse. At gross examination, both resected femoral heads showed extensive opaque yellow areas consistent with osteonecrosis. Microscopic examination of these areas revealed evidence of both extensive fracture and callus formation, as well as necrosis throughout, indicating that the osteonecrosis observed in this case was a secondary phenomenon superimposed on pre-existing osteoarthritis and subchondral fracture. There were many pseudogranulomatous lesions in the marrow space and necrotic area, where tiny fragments of bone and articular cartilage, surrounded by histiocytes and giant cells, were embedded, such as are typically seen in rapidly destructive arthrosis. No radiologic or morphologic evidence of primary osteonecrosis was noted. This case indicates that at least some cases of rapidly destructive arthritis are the result of subchondral fracture with superimposed secondary osteonecrosis. (orig.)

  10. Carpometacarpal subchondral cysts due to repetitive movements in shoemaker: a case report.

    Science.gov (United States)

    Tonini, Stefano; Candura, Stefano M; Lanfranco, Andrea; Mennoia, N Valerio

    2011-12-01

    Subchondral carpometacarpal cysts are classic and almost pathognomonic lesions found in workers using vibrating instruments over prolonged periods of time. We present the case of a 53-year-old woman who worked for 30 years sewing shoe uppers, a task which required grasping firmly a pear-shaped handle awl and pushing it through the leather upper and the sole of the shoe, with combined flexion and supination movement of the wrist. After approximately 20 years of working, the patient noted gradual onset of paresthesias in the dominant (right) hand, with increasing difficulty in grasping the awl. Subsequent diagnosis of carpal tunnel syndrome was confirmed by electrophysiologic testing and its surgical release was performed. Nevertheless, hand pain, paresthesias and weakness persisted. Ultrasound of the snuffbox tendons excluded DeQuervain tenosynovitis. Radiographic imaging of the symptomatic hand showed carpometacarpal subchondral cystic formations. In addition to demonstrating the usefulness of radiographic imaging in patients with persistent hand pain post-carpal release, this case is important in illustrating that repetitive movements with high pressure over the palmar carpal area may cause bone cysts, even if the subjects do not use vibrating tools.

  11. Visualisation of subchondral erosion in rat monoarticular arthritis by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Carpenter, T.A.; Everett, J.R.; Hall, L.D.; Harper, G.P.; Hodgson, R.J.; James, M.F.

    1995-01-01

    High-resolution magnetic resonance imaging (MRI) was used to investigate antigen-induced monoarticular arthritis (AIMA) in the rat. In sagittal, spin-echo images of the knee, characteristic parallel bands, in the order dark-light-dark, were consistently observed 5-8 days after arthritis induction; the bands ran concentric with, and just beneath, the femoral and tibial articular surfaces. Concurrent radiology, histology and MRI (chemical shift-selective imaging and contrast enhancement with magnetisation transfer and gadolinium) established that the phenomenon reflected subchondral erosion, not artefact. The outer hypointense band corresponded to calcified cartilage underlying the articular surface. The central hyperintense band reflected inflammatory matrix displacing normal haematopoietic tissue immediately subchondrally; here, trabecular bone had mostly disappeared, but adjacent articular cartilage, although under attack and lacking proteoglycan, appeared structurally normal. The inner hypointense band reflected deeper, truncated trabeculae within inflammatory matrix, layered with pallisading osteoblast-like cells. This study exemplifies the power of MRI for revealing localised joint pathology non-invasively, and shows that rat AIMA shares many pathological features with arthritis in human beings. (orig.)

  12. Reseeding of mussels on denuded rocky shores: preliminary studies ...

    African Journals Online (AJOL)

    A method is developed to establish clumps of mussels Perna perna in denuded areas on high-energy rocky shores on the south-east coast of South Africa. A total of 20 small (20–30 mm total length) mussels is placed under a 30 cm half-section of perforated PVC drainage pipe bolted to the rock surface. The pipe is left in ...

  13. Decrease in local volumetric bone mineral density (vBMD) in osteoarthritic joints is associated with the increase in cartilage damage: a pQCT study

    Science.gov (United States)

    Tamaddon, Maryam; Chen, Shen Mao; Vanaclocha, Leyre; Hart, Alister; El-Husseiny, Moataz; Henckel, Johann; Liu, Chaozong

    2017-11-01

    Osteoarthritis (OA) is the most common type of arthritis and a major cause of disability in the adult population. It affects both cartilage and subchondral bone in the joints. There has been some progress in understanding the changes in subchondral bone with progression of osteoarthritis. However, local changes in subchondral bone such as microstructure or volumetric bone mineral density in connection with the defect in cartilage are relatively unexplored. To develop an effective treatment for progression of OA, it is important to understand how the physical environment provided by the subchondral bone affects the overlying cartilage. In this study we examined the volumetric bone mineral density (vBMD) distribution in the osteoarthritic joint tissues obtained from total hip replacement surgeries due to osteoarthritis, using peripheral quantitative CT (pQCT). It was found that there is a significant decrease in volumetric bone mineral density, which co-localises with the damage in the overlying cartilage. This was not limited to the subchondral bone immediately adjacent to the cartilage defect but continued in the layers below. Bone resorption and cyst formation in the OA tissues were also detected. We observed that the bone surrounding subchondral bone cysts exhibited much higher volumetric bone mineral density than that of the surrounding bones. PQCT was able to detect significant changes in vBMD between OA and non-OA samples, as well as between areas of different cartilage degeneration, which points to its potential as a technique for detection of early OA.

  14. Repopulation of denuded tracheal grafts with alveolar type II cells

    International Nuclear Information System (INIS)

    Johnson, N.F.

    1988-01-01

    Repopulation of denuded heterotopic tracheal grafts with populations of specific epithelial cell types is one approach to study the differentiation potential of various cell types. This technique has been adopted to delineate the differentiation pathways of alveolar type II cells isolated from rat lungs. Under the conditions of this experiment, the reestablished epithelial lining was alveolar-like, however, ultrastructural analysis of the cells showed them to be like Clara cells. These preliminary results suggest that the secretary cells of the lung parenchyma and terminal airways may share a common ancestry. (author)

  15. Assessment of Cortical and Trabecular Bone Changes in Two Models of Post-Traumatic Osteoarthritis

    Science.gov (United States)

    Pauly, Hannah M; Larson, Blair E; Coatney, Garrett A; Button, Keith D.; DeCamp, Charlie E; Fajardo, Ryan S; Haut, Roger C; Donahue, Tammy L Haut

    2015-01-01

    Subchondral bone is thought to play a significant role in the initiation and progression of the post-traumatic osteoarthritis. The goal of this study was to document changes in tibial and femoral subchondral bone that occur as a result of two lapine models of anterior cruciate ligament injury, a modified ACL transection model and a closed-joint traumatic compressive impact model. Twelve weeks post-injury bones were scanned via micro-computed tomography. The subchondral bone of injured limbs from both models showed decreases in bone volume and bone mineral density. Surgical transection animals showed significant bone changes primarily in the medial hemijoint of femurs and tibias, while significant changes were noted in both the medial and lateral hemijoints of both bones for traumatic impact animals. It is believed that subchondral bone changes in the medial hemijoint were likely caused by compromised soft tissue structures seen in both models. Subchondral bone changes in the lateral hemijoint of traumatic impact animals are thought to be due to transmission of the compressive impact force through the joint. The joint-wide bone changes shown in the traumatic impact model were similar to clinical findings from studies investigating the progression of osteoarthritis in humans. PMID:26147652

  16. The Use of Tomosynthesis in the Global Study of Knee Subchondral Insufficiency Fractures.

    Science.gov (United States)

    Nelson, Fred; Bokhari, Omaima; Oravec, Daniel; Kim, Woong; Flynn, Michael; Lumley, Catherine; McPhilamy, Austin; Yeni, Yener N

    2017-02-01

    Subchondral insufficiency fractures (SIF), previously termed spontaneous osteonecrosis of the knee, are marked by a sudden onset of severe pain. Other than the size of the lesion, prediction for progression to joint replacement is difficult. The objective was to determine if quantitative analysis of bone texture using digital tomosynthesis imaging would be useful in predicting more rapid progression to joint replacement. Tomosynthesis studies of 30 knees with documented SIF were quantified by fractal, mean intercept length (MIL), and line fraction deviation analyses. Fractal dimension, lacunarity, MIL, and line fraction deviation variables measured from these analyses were then correlated to short interval progression to joint replacement surgery. Higher odds for joint replacement were related to higher values of the standard deviation of slope lacunarity and to morphometric measures (eg, MIL). Using digital tomosynthesis images for bone texture assessment may help distinguish condylar bone response in SIF, potentially acting as a clinically relevant predictive tool. In the future, contrasting SIF to the more gradual long-term process of osteoarthritis, there may be a better understanding of the different mechanisms for the two conditions. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  17. Post-earthquake denudation and its impacts on ancient civilizations in the Chengdu Longmenshan region, China

    Science.gov (United States)

    Chen, Ningsheng; Li, Jun; Liu, Lihong; Yang, Chenglin; Liu, Mei

    2018-05-01

    This study characterizes significant changes in denudation and disasters in mountainous areas induced in the humid Chengdu Longmenshan region by the Wenchuan Earthquake in 2008. A study focusing on the Longxi-Baisha River Basin was conducted to investigate the amount of denudation triggered by specific flash flood and debris flow events in 2009-2014. The following results were obtained through a comparison of pre-seismic regional denudation rates and denudation characteristics of other seismically active mountain regions. (1) Regional denudation processes occurred in a wave-like process of initial increase then decline, with a peak exhibiting a hyperbolic attenuation trend. This trend indicates that the denudation rate in the Chengdu Longmenshan region is expected to return to the pre-seismic rate of 0.3 mm a-1 after 81 years. In 22 years after the earthquake (Year 2030), debris flow disasters are expected to be rare. (2) Disasters increased significantly in the Chengdu Longmenshan region after the Wenchuan earthquake, with an average of 29.5 people missing or dead per year (22 times greater than the pre-earthquake rate) and average economic losses of 192 million Yuan per year (1.6 times greater than the pre-earthquake rate). (3) The denudation process was jointly controlled by the quantities of loose solid material and precipitation after the Wenchuan earthquake. The amount of loose solid material influenced the extent of denudation, while vegetation coverage rates and soil consolidation determined the overall denudation trend in the region, and changes in precipitation led to denudation fluctuations. (4) The results can be used to analyze the relationship between the potential flash flood-debris flow disasters after earthquakes in the ancient Shu kingdom and changes in historical social settlements. The results can also be used to predict denudation processes and disaster risks from earthquakes in humid mountainous regions around the world, such as the southern

  18. Denuded zone in Czochralski silicon wafer with high carbon content

    International Nuclear Information System (INIS)

    Chen Jiahe; Yang Deren; Ma Xiangyang; Que Duanlin

    2006-01-01

    The thermal stability of the denuded zone (DZ) created by high-low-high-temperature annealing in high carbon content (H[C]) and low carbon content (L[C]) Czochralski silicon (Cz-Si) has been investigated in a subsequent ramping and isothermal 1050 deg. C annealing. The tiny oxygen precipitates which might occur in the DZ were checked. It was found in the L[C] Cz-Si that the DZ shrank and the density of bulk micro-defects (BMDs) reduced with the increase of time spent at 1050 deg. C. Also, the DZs above 15 μm of thickness present in the H[C] Cz-Si wafers continuously and the density and total volume of BMDs first decreased then increased and finally decreased again during the treatments. Moreover, tiny oxygen precipitates were hardly generated inside the DZs, indicating that H[C] Cz-Si wafers could support the fabrication of integrated circuits

  19. Denuded zone in Czochralski silicon wafer with high carbon content

    Science.gov (United States)

    Chen, Jiahe; Yang, Deren; Ma, Xiangyang; Que, Duanlin

    2006-12-01

    The thermal stability of the denuded zone (DZ) created by high-low-high-temperature annealing in high carbon content (H[C]) and low carbon content (L[C]) Czochralski silicon (Cz-Si) has been investigated in a subsequent ramping and isothermal 1050 °C annealing. The tiny oxygen precipitates which might occur in the DZ were checked. It was found in the L[C] Cz-Si that the DZ shrank and the density of bulk micro-defects (BMDs) reduced with the increase of time spent at 1050 °C. Also, the DZs above 15 µm of thickness present in the H[C] Cz-Si wafers continuously and the density and total volume of BMDs first decreased then increased and finally decreased again during the treatments. Moreover, tiny oxygen precipitates were hardly generated inside the DZs, indicating that H[C] Cz-Si wafers could support the fabrication of integrated circuits.

  20. Effect of antiresorptive and anabolic bone therapy on development of osteoarthritis in a posttraumatic rat model of OA

    OpenAIRE

    Bagi, Cedo M.; Berryman, Edwin; Zakur, David E.; Wilkie, Dean; Andresen, Catharine J.

    2015-01-01

    Introduction Osteoarthritis (OA) is a leading cause of disability, but despite the high unmet clinical need and extensive research seeking dependable therapeutic interventions, no proven disease-modifying treatment for OA is currently available. Due to the close interaction and interplay between the articular cartilage and the subchondral bone plate, it has been hypothesized that antiresorptive drugs can also reduce cartilage degradation, inhibit excessive turnover of the subchondral bone pla...

  1. Cement stress predictions after anatomic total shoulder arthroplasty are correlated with preoperative glenoid bone quality.

    Science.gov (United States)

    Terrier, Alexandre; Obrist, Raphaël; Becce, Fabio; Farron, Alain

    2017-09-01

    We hypothesized that biomechanical parameters typically associated with glenoid implant failure after anatomic total shoulder arthroplasty (aTSA) would be correlated with preoperative glenoid bone quality. We developed an objective automated method to quantify preoperative glenoid bone quality in different volumes of interest (VOIs): cortical bone, subchondral cortical plate, subchondral bone after reaming, subchondral trabecular bone, and successive layers of trabecular bone. Average computed tomography (CT) numbers (in Hounsfield units [HU]) were measured in each VOI from preoperative CT scans. In parallel, we built patient-specific finite element models of simulated aTSAs to predict cement stress, bone-cement interfacial stress, and bone strain around the glenoid implant. CT measurements and finite element predictions were obtained for 20 patients undergoing aTSA for primary glenohumeral osteoarthritis. We tested all linear correlations between preoperative patient characteristics (age, sex, height, weight, glenoid bone quality) and biomechanical predictions (cement stress, bone-cement interfacial stress, bone strain). Average CT numbers gradually decreased from cortical (717 HU) to subchondral and trabecular (362 HU) bone. Peak cement stress (4-10 MPa) was located within the keel hole, above the keel, or behind the glenoid implant backside. Cement stress, bone-cement interfacial stress, and bone strain were strongly negatively correlated with preoperative glenoid bone quality, particularly in VOIs behind the implant backside (subchondral trabecular bone) but also in deeper trabecular VOIs. Our numerical study suggests that preoperative glenoid bone quality is an important parameter to consider in aTSA, which may be associated with aseptic loosening of the glenoid implant. These initial results should now be confronted with clinical and radiologic outcomes. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc

  2. Covalent binding of bone morphogenetic protein-2 and transforming growth factor-β3 to 3D plotted scaffolds for osteochondral tissue regeneration

    NARCIS (Netherlands)

    Di Luca, Andrea; Klein Gunnewiek, Michel; Vancso, Julius; van Blitterswijk, Clemens; Benetti, Edmondo Maria; Moroni, Lorenzo

    2017-01-01

    Engineering the osteochondral tissue presents some challenges mainly relying in its function of transition from the subchondral bone to articular cartilage and the gradual variation in several biological, mechanical, and structural features. A possible solution for osteochondral regeneration might

  3. Denuder for measuring emissions of gaseous organic exhaust gas constituents; Denuder zur Emissionsmessung von gasfoermigen organischen Abgasinhaltsstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Gerchel, B; Jockel, W; Kallinger, G; Niessner, R

    1997-05-01

    Industrial plants which emit carcinogenic or other noxious substances should be given top priority in any policy to ward off harmful environmental effects. This also applies to many volatile and semi-volatile air constituents such as volatile aliphatic carbonyls or amines. To date there are no satisfactory methods for determining trace organic components of exhaust gases. It is true that aldehydes are considered in the VDI Guideline 3862, but the measuring methods given there are based on absorption in liquids and are accordingly difficult to use and show a high cross-sensitivity for other substances. No VDI Guideline exists to date on amine emissions. In view of the complexity of exhaust gases a selective enrichment of certain families of substances would appear indicated. Sampling trouble could be reduced if it was possible only to accumulate the gaseous phase, or even just one family of gaseous constituents. A particularly suitable air sampling method is that of diffusion separation. These diffusion separators (denuders) are well known as a powerful measuring system which is able to accumulate trace pollutants in the outside air. The purpose of the present study was to find out whether the concept of diffusion separation is also applicable to emission monitoring, and in particular whether it is suitable for detecting volatile aliphatic aldehydes and amines (primary and secondary) at extremely low concentrations (<10 ppb). (orig./SR) [Deutsch] Fuer Anlagen mit Emissionen von krebserzeugenden und gesundheitsgefaehrdenden Stoffen ergibt sich ein besonderer Handlungsbedarf zum Schutz vor schaedlichen Umwelteinwirkungen. Zu diesen Stoffen gehoeren auch viele leicht- und mittelfluechtigen Luftinhaltsstoffe, wie z.B. die leichtfluechtigen aliphatischen Carbonyle oder Amine. Fuer organische Komponenten, die nur in geringen Konzentrationen im Abgas vorkommen, existieren bisher keine zufriedenstellenden Messverfahren. Fuer die Aldehyde liegt zwar die VDI-Richtlinie 3862

  4. Neuroependymal Denudation is in Progress in Full-term Human Foetal Spina Bifida Aperta

    NARCIS (Netherlands)

    Sival, Deborah A.; Guerra, Montserrat; den Dunnen, Wilfred F. A.; Batiz, Luis F.; Alvial, Genaro; Castaneyra-Perdomo, Agustin; Rodriguez, Esteban M.

    In human spina bifida aperta (SBA), cerebral pathogenesis [hydrocephalus, Sylvius aqueduct (SA) stenosis and heterotopias] is poorly understood. In animal models, loss of ventricular lining (ependymal denudation) causes SA stenosis and hydrocephalus. We aimed to investigate whether ependymal

  5. Quantitative Assessment of Degenerative Cartilage and Subchondral Bony Lesions in a Preserved Cadaveric Knee: Propagation-Based Phase-Contrast CT Versus Conventional MRI and CT.

    Science.gov (United States)

    Geith, Tobias; Brun, Emmanuel; Mittone, Alberto; Gasilov, Sergei; Weber, Loriane; Adam-Neumair, Silvia; Bravin, Alberto; Reiser, Maximilian; Coan, Paola; Horng, Annie

    2018-04-09

    The aim of this study was to quantitatively assess hyaline cartilage and subchondral bone conditions in a fully preserved cadaveric human knee joint using high-resolution x-ray propagation-based phase-contrast imaging (PBI) CT and to compare the performance of the new technique with conventional CT and MRI. A cadaveric human knee was examined using an x-ray beam of 60 keV, a detector with a 90-mm 2 FOV, and a pixel size of 46 × 46 μm 2 . PBI CT images were reconstructed with both the filtered back projection algorithm and the equally sloped tomography method. Conventional 3-T MRI and CT were also performed. Measurements of cartilage thickness, cartilage lesions, International Cartilage Repair Society scoring, and detection of subchondral bone changes were evaluated. Visual inspection of the specimen akin to arthroscopy was conducted and served as a standard of reference for lesion detection. Loss of cartilage height was visible on PBI CT and MRI. Quantification of cartilage thickness showed a strong correlation between the two modalities. Cartilage lesions appeared darker than the adjacent cartilage on PBI CT. PBI CT showed similar agreement to MRI for depicting cartilage substance defects or lesions compared with the visual inspection. The assessment of subchondral bone cysts showed moderate to strong agreement between PBI CT and CT. In contrast to the standard clinical methods of MRI and CT, PBI CT is able to simultaneously depict cartilage and bony changes at high resolution. Though still an experimental technique, PBI CT is a promising high-resolution imaging method to evaluate comprehensive changes of osteoarthritic disease in a clinical setting.

  6. Response of induced bone defects in horses to collagen matrix containing the human parathyroid hormone gene.

    Science.gov (United States)

    Backstrom, Kristin C; Bertone, Alicia L; Wisner, Erik R; Weisbrode, Stephen E

    2004-09-01

    To determine whether human parathyroid hormone (hPTH) gene in collagen matrix could safely promote bone formation in diaphyseal or subchondral bones of horses. 8 clinically normal adult horses. Amount, rate, and quality of bone healing for 13 weeks were determined by use of radiography, quantitative computed tomography, and histomorphometric analysis. Diaphyseal cortex and subchondral bone defects of metacarpi were filled with hPTH(1-34) gene-activated matrix (GAM) or remained untreated. Joints were assessed on the basis of circumference, synovial fluid analysis, pain on flexion, lameness, and gross and histologic examination. Bone volume index was greater for cortical defects treated with hPTH(1-34) GAM, compared with untreated defects. Bone production in cortical defects treated with hPTH(1-34) GAM positively correlated with native bone formation in untreated defects. In contrast, less bone was detected in hPTH(1-34) GAM-treated subchondral bone defects, compared with untreated defects, and histology confirmed poorer healing and residual collagen sponge. Use of hPTH(1-34) GAM induced greater total bone, specifically periosteal bone, after 13 weeks of healing in cortical defects of horses. The hPTH(1-34) GAM impeded healing of subchondral bone but was biocompatible with joint tissues. Promotion of periosteal bone formation may be beneficial for healing of cortical fractures in horses, but the delay in onset of bone formation may negate benefits. The hPTH(1-34) GAM used in this study should not be placed in articular subchondral bone defects, but contact with articular surfaces is unlikely to cause short-term adverse effects.

  7. Subchondral insufficiency fractures of the femoral head: associated imaging findings and predictors of clinical progression

    Energy Technology Data Exchange (ETDEWEB)

    Hackney, Lauren A.; Joseph, Gabby B.; Link, Thomas M. [University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Lee, Min Hee [University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of); Vail, Thomas P. [University of California, Department of Orthopaedic Surgery, San Francisco, CA (United States)

    2016-06-15

    To characterize the morphology and imaging findings of femoral head subchondral insufficiency fractures (SIF), and to investigate clinical outcomes in relation to imaging findings. Fifty-one patients with hip/pelvis magnetic resonance (MR) images and typical SIF characteristics were identified and reviewed by two radiologists. Thirty-five patients had follow-up documentation allowing assessment of clinical outcome. Subgroup comparisons were performed using regression models adjusted for age and body mass index. SIF were frequently associated with cartilage loss (35/47, 74.5 %), effusion (33/42, 78.6 %), synovitis (29/44, 66 %), and bone marrow oedema pattern (BMEP) (average cross-sectional area 885.7 ± 730.2 mm{sup 2}). Total hip arthroplasty (THA) was required in 16/35 patients, at an average of 6 months post-MRI. Compared to the THA cohort, the non-THA group had significantly (p < 0.05) smaller overlying cartilage defect size (10 mm vs. 29 mm), smaller band length ratio and fracture diameters, and greater incidence of parallel fracture morphology (p < 0.05). Male gender and increased age were significantly associated with progression, p < 0.05. SIF were associated with synovitis, cartilage loss, effusion, and BMEP. Male gender and increased age had a significant association with progression to THA, as did band length ratio, fracture diameter, cartilage defect size, and fracture deformity/morphology. (orig.)

  8. Decreased Lumbar Lordosis and Deficient Acetabular Coverage Are Risk Factors for Subchondral Insufficiency Fracture.

    Science.gov (United States)

    Jo, Woo Lam; Lee, Woo Suk; Chae, Dong Sik; Yang, Ick Hwan; Lee, Kyoung Min; Koo, Kyung Hoi

    2016-10-01

    Subchondral insufficiency fracture (SIF) of the femoral head occurs in the elderly and recipients of organ transplantation. Osteoporosis and deficient lateral coverage of the acetabulum are known risk factors for SIF. There has been no study about relation between spinopelvic alignment and anterior acetabular coverage with SIF. We therefore asked whether a decrease of lumbar lordosis and a deficiency in the anterior acetabular coverage are risk factors. We investigated 37 patients with SIF. There were 33 women and 4 men, and their mean age was 71.5 years (59-85 years). These 37 patients were matched with 37 controls for gender, age, height, weight, body mass index and bone mineral density. We compared the lumbar lordosis, pelvic incidence, pelvic tilt, sacral slope, acetabular index, acetabular roof angle, acetabular head index, anterior center-edge angle and lateral center-edge angle. Lumbar lordosis, pelvic tilt, sacral slope, lateral center edge angle, anterior center edge angle, acetabular index and acetabular head index were significantly different between SIF group and control group. Lumbar lordosis (OR = 1.11), lateral center edge angle (OR = 1.30) and anterior center edge angle (OR = 1.27) had significant associations in multivariate analysis. Decreased lumbar lordosis and deficient anterior coverage of the acetabulum are risk factors for SIF as well as decreased lateral coverage of the acetabulum.

  9. Tibiofemoral subchondral surface ratio (SSR) is a predictor of osteoarthritis symptoms and radiographic progression: data from the Osteoarthritis Initiative (OAI).

    Science.gov (United States)

    Everhart, J S; Siston, R A; Flanigan, D C

    2014-06-01

    Symptomatic knee osteoarthritis (OA) is poorly correlated with radiographic severity, but subchondral bone measures may be useful for risk assessment as bone shape is grossly unaffected at early radiographic stages. We sought to determine whether compartment-specific size mismatch in the naturally asymmetric tibiofemoral joint, measured as tibiofemoral subchondral surface ratio (SSR): (1) predicts incident symptoms, (2) predicts incident or progressive OA, (3) is reproducible and time invariant. OA Initiative participants with baseline MRIs and up to 48-month follow-up (n = 1,338) were analyzed. Logistic regression was used to determine the association between SSR and incident symptoms, incident OA, and progression of OA after adjusting for demographic, radiologic, injury-related, and lifestyle-related factors. Reproducibility was assessed as % coefficient of variation (CV) on repeat MRI studies at baseline and 24 months. Increased medial SSR is protective against incident symptoms at 48 months (per 0.1 increase: OR 0.48 CI 0.30, 0.75; P = 0.001). Increased lateral SSR values are protective against lateral OA incidence (OR 0.23 CI 0.06, 0.77; P = 0.016) or progression (OR 0.66 CI 0.43, 0.99; P = 0.049) at 24 months. Both medial and lateral SSR are stable over time (medial: mean change 0.001 SD 0.016; lateral: mean change 0.000 SD 0.017) and are highly reproducible (3.0% CV medial SSR; 2.7% CV lateral SSR). A larger medial SSR is protective against developing OA-related symptoms. A larger lateral SSR is protective against lateral OA incidence or progression. Finally, lateral and medial SSR are stable over time and are highly reproducible across MRI studies. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  10. Cooling and denudation history of the Rokko area, southwest Japan, based on fission-track thermochronology

    International Nuclear Information System (INIS)

    Sueoka, Shigeru; Tagami, Takahiro; Tsutsumi, Hiroyuki; Hasebe, Noriko; Tamura, Akihiro; Arai, Shoji; Yamada, Ryuji; Matsuda, Tatsuo; Omura, Kentaro

    2010-01-01

    Quantitatively estimating denudation is generally difficult because it essentially involves the removal and loss of materials in situ. The denudation rate of mountainous areas in Japan has commonly been studied from the volume of sediment in a basin or catchment. Nonetheless, the availability of these methods is constrained spatially by upstream area and temporally by depositional age. In the last few decades, thermochronometric methods that evaluate thermal history using radiometric-dating methods have been used to evaluate the denudation and tectonic history of orogenic belts around the world. The advantages of thermochronometric methods are that we can calculate the denudation rate at each sampling point and that combining multiple methods and/or target minerals enables us to calculate denudation rates in multiple periods. However, thermochronometric methods have been applied to areas with extraordinarily high denudation rates in island arc areas such as Japan. Thus, the effectiveness of thermochronometric methods for estimating denudation rates in island arc areas has not been demonstrated. We applied apatite and zircon fission-track thermochronometry to granitic rock samples collected from outcrops and a borehole to estimate the tectonic history of the Rokko area, southwest Japan. Previous studies suggested that the Rokko Mountains have been uplifted by active faulting along their northern and southern margins during the Rokko movements, a Quaternary tectonic movement in the Kinki district. However, the tectonic history of the Rokko area prior to 1 Ma has not been revealed due to a lack of prevalent geologic markers. We estimated average denudation rates in various periods based on apatite and zircon FT ages and previously reported radiometric ages. We obtained denudation rates at about 0.04-0.10 mm/yr after about 30 Ma, 0.05-0.7 mm/yr during 50-30 Ma, 0.7-4.0 mm/yr during 70-50 Ma. The denudation rate after the deposition of the Kobe Group (36.9-30.4 Ma) is

  11. Subchondral cysts of the tibia secondary to osteoarthritis of the knee

    International Nuclear Information System (INIS)

    Ostlere, S.J.; Seeger, L.L.; Eckardt, J.J.

    1990-01-01

    Subchondral cysts of the tibia secondary to osteoarthritis of the knee are not usually seen on radiographs. When present, they are typically small and present no diagnostic difficulty. Two cases of unusually large subchondral lesions of the medial tibial plateau are presented. The lesions were well defined and lay adjacent to the medial tibial cortex with their long axes in the sagittal plane. Both were associated with moderate medial compartment osteoarthritis. Additional information obtained from computed tomography indicated that these lesions were subchondral cysts secondary to osteoarthritis rather than tumors or other tumor-like conditions. (orig.)

  12. Traumatic subchondral fracture of the femoral head in a healed trochanteric fracture.

    Science.gov (United States)

    Lee, Sang Yang; Niikura, Takahiro; Iwakura, Takashi; Kurosaka, Masahiro

    2014-07-11

    An 82-year-old woman sustained a trochanteric fracture of the left femur after a fall. Fracture fixation was performed using proximal femoral nail antirotation (PFNA) II, and she was able to walk with a T-cane after 3 months. Eleven months following the operation, the patient presented with left hip pain after a fall. Radiographs showed a subchondral collapse of the femoral head located above the blade tip. The authors removed the PFNA-II and subsequently performed cemented bipolar hemiarthroplasty. Histological evaluation of the femoral head showed osteoporosis with no evidence of osteonecrosis. Repair tissue, granulation tissue and callus formation were seen at the collapsed subchondral area. Based on these findings, a traumatic subchondral fracture of the femoral head in a healed trochanteric fracture was diagnosed. A traumatic subchondral fracture of the femoral head may need to be considered as a possible diagnosis after internal fixation of the trochanteric fracture. 2014 BMJ Publishing Group Ltd.

  13. Release of mercury halides from KCl denuders in the presence of ozone

    Directory of Open Access Journals (Sweden)

    S. N. Lyman

    2010-09-01

    Full Text Available KCl-coated denuders have become a standard method for measurement of gaseous oxidized mercury, but their performance has not been exhaustively evaluated, especially in field conditions. In this study, KCl-coated and uncoated quartz denuders loaded with HgCl2 and HgBr2 lost 29–55% of these compounds, apparently as elemental mercury, when exposed to ozone (range of 6–100 ppb tested. This effect was also observed for denuders loaded with gaseous oxidized mercury at a field site in Nevada (3–37% of oxidized mercury lost. In addition, collection efficiency decreased by 12–30% for denuders exposed to 50 ppb ozone during collection of HgCl2. While data presented were obtained from laboratory tests and as such do not exactly simulate field sampling conditions, these results indicate that the KCl denuder oxidized mercury collection method may not be as robust as previously thought. This work highlights needs for further testing of this method, clear identification of gaseous oxidized mercury compounds in the atmosphere, and development of field calibration methods for these compounds.

  14. One million years of glaciation and denudation history in west Greenland

    DEFF Research Database (Denmark)

    Strunk, Astrid; Knudsen, Mads Faurschou; Egholm, David Lundbek

    2017-01-01

    The influence of major Quaternary climatic changes on growth and decay of the Greenland Ice Sheet, and associated erosional impact on the landscapes, is virtually unknown beyond the last deglaciation. Here we quantify exposure and denudation histories in west Greenland by applying a novel Markov......-Chain Monte Carlo modelling approach to all available paired cosmogenic 10Be-26Al bedrock data from Greenland. We find that long-term denudation rates in west Greenland range from >50 m Myr−1 in low-lying areas to ∼2 m Myr−1 at high elevations, hereby quantifying systematic variations in denudation rate among...... different glacial landforms caused by variations in ice thickness across the landscape. We furthermore show that the present day ice-free areas only were ice covered ca. 45% of the past 1 million years, and even less at high-elevation sites, implying that the Greenland Ice Sheet for much of the time...

  15. Denudation history of the Snowy Mountains: constraints from apatite fission track thermochronology

    International Nuclear Information System (INIS)

    Kohn, B.P.; Gleadow, A.J.W.; Cox, S.J.D.

    1999-01-01

    Apatite fission track thermo chronology from Early Palaeozoic granitoids centred around the Kosciuszko massif of the Snowy Mountains, records a denudation history that was episodic and highly variable. The form of the apatite fission track age profile assembled from vertical sections and hydro-electric tunnels traversing the mountains, together with numerical forward modelling, provide strong evidence for two episodes of accelerated denudation, commencing in Late Permian - Early Triassic (ca 270 250 Ma) and mid-Cretaceous (ca 110-100 Ma) times, and a possible third episode in the Cenozoic. Denudation commencing in the Late Permian - Early Triassic wins widespread in the eastern and Central Snowy Mountains area, continued through much of the Triassic, and amounted to at least ∼2.0-2,4 km. This episode was probably the geomorphic response to the Hunter-Bowen Orogeny. Post-Triassic denudation to the present in these areas amounted to ∼2.0-2.2 km. Unambiguous evidence for mid-Cretaceous cooling and possible later cooling is confined to a north-south-trending sinuous belt, up to ∼15km wide by at least 35km long, of major reactivated Palaeozoic faults on the western side of the mountains. This zone is the most deeply exposed area of the Kosciuszko block. Denudation accompanying these later events totalled up to ∼1.8-2.0 km and ∼2.0 2.25 km respectively. Mid-Cretaceous denudation marks the onset of renewed tectonic activity in the south-eastern highlands following a period of relative quiescence since the Late Triassic, and establishes a temporal link with the onset of extension related to the opening of the Tasman Sea. Much of the present day relief of the mountains resulted from surface uplift which disrupted the post-mid-Cretaceous apatite fission track profile by variable offsets on faults. Copyright (1999) Geological Society of Australia

  16. Effects of long-term estrogen replacement therapy on bone turnover in periarticular tibial osteophytes in surgically postmenopausal cynomolgus monkeys

    OpenAIRE

    Olson, Erik J.; Lindgren, Bruce R.; Carlson, Cathy S.

    2007-01-01

    The aims of the present study were to assess the effects of long-term estrogen replacement therapy (ERT) on size and indices of bone turnover in periarticular osteophytes in ovariectomized cynomolgus monkeys and to compare dynamic indices of bone turnover in osteophyte bone with those of subchondral bone (SCB) and epiphyseal/metaphyseal cancellous (EMC) bone. One hundred sixty-five adult female cynomolgus macaques were bilaterally ovariectomized and randomly divided into three age- and weight...

  17. Detection of osteophytes and subchondral cysts in the knee with use of tomosynthesis.

    Science.gov (United States)

    Hayashi, Daichi; Xu, Li; Roemer, Frank W; Hunter, David J; Li, Ling; Katur, Avinash M; Guermazi, Ali

    2012-04-01

    To evaluate the diagnostic performance of tomosynthesis in depicting osteophytes and subchondral cysts, with use of magnetic resonance (MR) imaging as the reference, and to test whether the lesions detected at radiography and tomosynthesis are associated with pain. The study was approved by local institutional review board, and all subjects gave written informed consent. Forty subjects (80 knees) older than 40 years were recruited irrespective of knee pain or radiographic osteoarthritis. Knees were imaged with radiography, tomosynthesis, and MR imaging. Presence of osteophytes and subchondral cysts in four locations of tibiofemoral joint (medial and lateral femur and tibia) was recorded. Knee pain was assessed by using the Western Ontario and McMaster University pain subscale. MR imaging depicted 171 osteophytes and 51 subchondral cysts. Tomosynthesis had a higher sensitivity for osteophyte detection in left and right lateral femur (0.96 vs 0.75, P = .025, and 1.00 vs 0.71, P = .008, respectively), right medial femur (0.94 vs 0.72, P = .046), and right lateral tibia (1.00 vs 0.83, P = .046). For subchondral cyst detection, the sensitivity of tomosynthesis was 0.14-1.00 and that of radiography was 0.00-0.56. Both modalities had similar specificity for both lesions. Subjects with tomosynthesis-depicted osteophytes (odds ratio, 4.2-6.4; P = .001-.011) and medially located subchondral cysts (odds ratio, 6.7-17.8; P = .004-.03) were more likely to feel pain than those without. However, radiography-depicted osteophytes were more strongly associated with pain than were tomosynthesis-depicted osteophytes. Tomosynthesis depicted more osteophytes and subchondral cysts than did radiography. Subjects with tomosynthesis-depicted osteophytes and subchondral cysts were more likely to feel pain than those without such lesions. © RSNA, 2012.

  18. Wet effluent diffusion denuder: The tool for determination of monoterpenes in forest

    Czech Academy of Sciences Publication Activity Database

    Křůmal, Kamil; Mikuška, Pavel; Večeřová, Kristýna; Urban, Otmar; Pallozzi, E.; Večeřa, Zbyněk

    2016-01-01

    Roč. 153, JUN (2016), s. 260-267 ISSN 0039-9140 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:68081715 ; RVO:67179843 Keywords : diffusion denuder * monoterpene * biogenic volatile organic compounds * tenax tubes Subject RIV: CB - Analytical Chemistry , Separation; EH - Ecology, Behaviour (UEK-B) Impact factor: 4.162, year: 2016

  19. Kinetically limited weathering at low denudation rates in semiarid climatic conditions

    Science.gov (United States)

    Schoonejans, Jérôme; Vanacker, Veerle; Opfergelt, Sophie; Ameijeiras-Mariño, Yolanda; Christl, Marcus

    2016-02-01

    Biogeochemical cycling within the Critical Zone depends on the interactions between minerals and fluids controlling chemical weathering and physical erosion rates. In this study, we explore the role of water availability in controlling soil chemical weathering in semiarid climatic conditions. Weathering rates and intensities were evaluated for nine soil profiles located on convex ridge crests of three mountain ranges in the Spanish Betic Cordillera. We combine a geochemical mass balance with 10Be cosmogenic nuclides to constrain chemical weathering intensities and long-term denudation rates. As such, this study presents new data on chemical weathering and 10Be-derived denudation for understudied semiarid climate systems. In the Betic Cordillera, chemical weathering intensities are relatively low (~5 to 30% of the total denudation of the soil) and negatively correlated with the magnitude of the water deficit in soils. Chemical mass losses are inversely related to denudation rates (14-109 mm/kyr) and positively to soil thickness (14-58 cm); these results are consistent with kinetic limitation of chemical weathering rates. A worldwide compilation of chemical weathering data suggests that soil water balance may regulate the coupling between chemical weathering and physical erosion by modulating soil solute fluxes. Therefore, future landscape evolution models that seek to link chemical weathering and physical erosion should include soil water flux as an essential driver of weathering.

  20. Researches on tectonic uplift and denudation with relation to geological disposal of HLW in Japan

    International Nuclear Information System (INIS)

    Fujiwara, Osamu; Sanga, Tomoji; Moriya, Toshifumi

    2005-01-01

    This paper reviews the present state of researches on tectonic uplift and denudation, and shows perspective goals and direction of future researches from the viewpoint of geological disposal of HLW in Japan. Detailed history of tectonics and denudation in geologic time scale, including the rates, temporal and spatial distributions and processes, reconstructed from geologic and geomorphologic evidences will enable us to make the geological predictions. Improvements of the analytic methods for the geological histories, e.g. identification of the tectonic and denudational imprints and age determinations, are indispensable for the accurate prediction. Developments of the tools and methodologies for assessments of the degree and extension of influences by the tectonic uplift, subsidence and denudation on the geological environments such as ground water flows are also fundamental problem in the study field of the geological disposal of HLW. Collaboration of scientific researches using the geological and geomorphological methods and applied technology, such as numerical simulations of ground water flows, is important in improving the safety and accuracy of the geological disposal of HLW. (author)

  1. Wet effluent diffusion denuder: The tool for determination of monoterpenes in forest

    Czech Academy of Sciences Publication Activity Database

    Křůmal, Kamil; Mikuška, Pavel; Večeřová, Kristýna; Urban, Otmar; Pallozzi, E.; Večeřa, Zbyněk

    2016-01-01

    Roč. 153, JUN (2016), s. 260-267 ISSN 0039-9140 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:68081715 ; RVO:67179843 Keywords : diffusion denuder * monoterpene * biogenic volatile organic compounds * tenax tubes Subject RIV: CB - Analytical Chemistry, Separation; EH - Ecology, Behaviour (UEK-B) Impact factor: 4.162, year: 2016

  2. Photoshop-based image analysis of canine articular cartilage after subchondral damage.

    Science.gov (United States)

    Lahm, A; Uhl, M; Lehr, H A; Ihling, C; Kreuz, P C; Haberstroh, J

    2004-09-01

    The validity of histopathological grading is a major problem in the assessment of articular cartilage. Calculating the cumulative strength of signal intensity of different stains gives information regarding the amount of proteoglycan, glycoproteins, etc. Using this system, we examined the medium-term effect of subchondral lesions on initially healthy articular cartilage. After cadaver studies, an animal model was created to produce pure subchondral damage without affecting the articular cartilage in 12 beagle dogs under MRI control. Quantification of the different stains was provided using a Photoshop-based image analysis (pixel analysis) with the histogram command 6 months after subchondral trauma. FLASH 3D sequences revealed intact cartilage after impact in all cases. The best detection of subchondral fractures was achieved with fat-suppressed TIRM sequences. Semiquantitative image analysis showed changes in proteoglycan and glycoprotein quantities in 9 of 12 samples that had not shown any evidence of damage during the initial examination. Correlation analysis showed a loss of the physiological distribution of proteoglycans and glycoproteins in the different zones of articular cartilage. Currently available software programs can be applied for comparative analysis of histologic stains of hyaline cartilage. After subchondral fractures, significant changes in the cartilage itself occur after 6 months.

  3. Present and past denudation rates in the central Tianshan (Central Asia): impact of the Quaternary glaciations?

    Science.gov (United States)

    Charreau, J.; Puchol, N.; Blard, P.; Braucher, R.; Leanni, L.; Bourles, D. L.; Graveleau, F.; Dominguez, S.

    2012-12-01

    Denudation controls the mass transfer from the uplifting highlands to the lowlands basin. It impacts the isostatic compensation and hence tectonics, the rheology and may drives the Earth climate through its potential impact on atmospheric CO2. Denudation is therefore a key factor governing the evolution of the Earth's surface. Quantitative records of past denudation rates over geological time scales are thus of major importance to untangle the complex interactions between tectonics, climate and surface processes. This is particularly true at the Plio-pleistocene transition where the onset of Quaternary glaciations may have enhanced worldwide denudation rates. The Tianshan stands out as a key area to better address these problems. This range owes its impressive present high topography to the recent deformation due to the India-Asia collision and is moreover sandwiched between two large intracontinental endorheic basins where the total material eroded from the uplifting range may be deciphered from the sedimentary archive. Moreover, here, potential changes in the sediment volume are insensitive to global sea-level variations. Accurate reconstruction of past denudation rate require well-dated sedimentary archives. Over past decades, several magnetostratigraphic studies were carried out in the piedmonts, where remarkable sedimentary sections are exposed in deep rivers entrenchment which expose the thick conglomeratic Xiyu formation, initially assigned to be Plio-pleistocene in age. This led several authors to conclude that, in this region, the sediment fluxes rapidly increaseed at the onset of glaciations. However, absolute magnetostratigraphic dating unambiguously show that this formation is highly diachronous and, therefore, can't owe its origin to a climate change. Given the strong lateral facies variations, reconstruction of past denudation rates from the sedimentary archive require detailed chronostratigraphy and a knowledge of the basin geometry, both almost

  4. Functional CT imaging: load-dependent visualization of the subchondral mineralization by means of CT osteoabsorptionmetry (CT-OAM); Funktionelle Computertomographie: Beanspruchungsabhaengige Darstellung der subchondralen Mineralisierung mittels CT gestuetzter Osteoabsorptiometrie (CTOAM)

    Energy Technology Data Exchange (ETDEWEB)

    Linsenmaier, U.; Schlichtenhorst, K.; Pfeifer, K.J.; Reiser, M. [Inst. fuer Klinische Radiologie, Innenstadt, Ludwig-Maximilians-Univ. Muenchen (Germany); Kersting, S.; Putz, R.; Mueller-Gerbl, M. [Anatomische Anstalt, Ludwig-Maximilians-Univ. Muenchen (Germany)

    2003-05-01

    Purpose: Functional computed tomography for visualization and quantification of subchondral bone mineralization using CT osteoabsorptiometry (CT-OAM). Materials and Methods: Tarsometatarsal (TMT) and metatarsophalangeal (MTP) joints of 46 human hallux valgus (HV) specimens were examined (sagittal 1/1/1 mm) on a single slice CT scanner SCT (Somatom Plus 4, Siemens AG). Subchondral bone pixels were segmented and assigned to 10 density value groups (triangle 100 HU, range 200 - 1200 HU) the pixels using volume rendering technique (VRT). The data analysis considered the severity of HV as determined by the radiographically measured HV-angle (a.p. projection). Results: CT-OAM could generate reproducible densitograms of the distribution pattern of the subchondral bone density for all four joint surfaces (TMT and MTP joints). The bone density localization enables the assignment to different groups, showing a characteristic HV-angle-dependent distribution of the maximum bone mineralization of the load-dependent densitogram (p < 0.001). Conclusion: CT-OAM is a functional CT technique for visualizing and quantifying the distribution of the subchondral bone density, enabling a noninvasive load-dependent assessment of the joint surfaces. Load-dependent densitograms of hallux valgus specimens show a characteristic correlation with an increase of the HV-angle. (orig.) [German] Ziel: Darstellung und Quantifizierung der subchondralen Mineralisierung in Abhaengigkeit von unterschiedlichen Beanspruchungssituationen mittels funktioneller Computertomographie als CT-Osteoabsorptiometrie (CT-OAM). Methode: An 46 humanen Praeparaten mit Hallux valgus (HV) wurden exemplarisch die TMT I (Tarsometatarsal)- und MTP I (Metatarsophalangeal)-Gelenke des ersten Strahles (sagittal 1/1/1 mm) an einem Singleslice Spiral-CT (SCT, Somatom Plus 4, Siemens AG) untersucht. Der subchondrale Knochen wurde segmentiert, den Pixel wurde mittels Volume Rendering Technik (VRT) 10 Graustufenbereiche (D100 HU

  5. Bone marrow oedema on MR imaging indicates ARCO stage 3 disease in patients with AVN of the femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Meier, Reinhard; Schaeffeler, Christoph; Waldt, Simone; Rummeny, Ernst J.; Woertler, Klaus [Klinikum rechts der Isar, Technische Universitaet Muenchen, Department of Diagnostic and Interventional Radiology, Munich (Germany); Kraus, Tobias M. [Klinikum rechts der Isar, Technische Universitaet Muenchen, Department of Orthopaedics, Munich (Germany); Berufsgenossenschaftliche Unfallklinik Tuebingen, Department of Trauma and Orthopaedics, Tuebingen (Germany); Torka, Sebastian [Klinikum rechts der Isar, Technische Universitaet Muenchen, Department of Orthopaedics, Munich (Germany); Berufsgenossenschaftliche Unfallklinik Murnau, Department of Trauma and Orthopaedics, Murnau (Germany); Schlitter, Anna Melissa; Specht, Katja [Klinikum rechts der Isar, Technische Universitaet Muenchen, Institute of Pathology, Munich (Germany); Haller, Bernhard [Klinikum rechts der Isar, Technische Universitaet Muenchen, Institute of Medical Statistics and Epidemiology, Munich (Germany); Rechl, Hans [Klinikum rechts der Isar, Technische Universitaet Muenchen, Department of Orthopaedics, Munich (Germany)

    2014-09-15

    To test the hypothesis that bone marrow oedema (BME) observed on MRI in patients with avascular necrosis (AVN) of the femoral head represents an indicator of subchondral fracture. Thirty-seven symptomatic hips of 27 consecutive patients (53 % women, mean age 49.2) with AVN of the femoral head and associated BME on magnetic resonance (MR) imaging were included. MR findings were correlated with computed tomography (CT) of the hip and confirmed by histopathological examination of the resected femoral head. Imaging studies were analysed by two radiologists with use of the ARCO classification. On MR imaging a fracture line could be identified in 19/37 (51 %) cases, which were classified as ARCO stage 3 (n = 15) and stage 4 (n = 4). The remaining 18/37 (49 %) cases were classified as ARCO stage 2. However, in all 37/37 (100 %) cases a subchondral fracture was identified on CT, indicating ARCO stage 3/4 disease. The extent of subchondral fractures and the femoral head collapse was graded higher on CT as compared to MRI (P < 0.05). Histopathological analysis confirmed bone necrosis and subchondral fractures. In patients with AVN, BME of the femoral head represents a secondary sign of subchondral fracture and thus indicates ARCO stage 3 disease. circle BME on MRI in AVN of femoral head indicates a subchondral fracture. (orig.)

  6. Bone marrow oedema on MR imaging indicates ARCO stage 3 disease in patients with AVN of the femoral head

    International Nuclear Information System (INIS)

    Meier, Reinhard; Schaeffeler, Christoph; Waldt, Simone; Rummeny, Ernst J.; Woertler, Klaus; Kraus, Tobias M.; Torka, Sebastian; Schlitter, Anna Melissa; Specht, Katja; Haller, Bernhard; Rechl, Hans

    2014-01-01

    To test the hypothesis that bone marrow oedema (BME) observed on MRI in patients with avascular necrosis (AVN) of the femoral head represents an indicator of subchondral fracture. Thirty-seven symptomatic hips of 27 consecutive patients (53 % women, mean age 49.2) with AVN of the femoral head and associated BME on magnetic resonance (MR) imaging were included. MR findings were correlated with computed tomography (CT) of the hip and confirmed by histopathological examination of the resected femoral head. Imaging studies were analysed by two radiologists with use of the ARCO classification. On MR imaging a fracture line could be identified in 19/37 (51 %) cases, which were classified as ARCO stage 3 (n = 15) and stage 4 (n = 4). The remaining 18/37 (49 %) cases were classified as ARCO stage 2. However, in all 37/37 (100 %) cases a subchondral fracture was identified on CT, indicating ARCO stage 3/4 disease. The extent of subchondral fractures and the femoral head collapse was graded higher on CT as compared to MRI (P < 0.05). Histopathological analysis confirmed bone necrosis and subchondral fractures. In patients with AVN, BME of the femoral head represents a secondary sign of subchondral fracture and thus indicates ARCO stage 3 disease. circle BME on MRI in AVN of femoral head indicates a subchondral fracture. (orig.)

  7. Osteoarthritis of the knee: correlation of subchondral MR signal abnormalities with histopathologic and radiographic features

    International Nuclear Information System (INIS)

    Bergman, A.G.; Willen, H.K.; Lindstrand, A.L.; Pettersson, H.T.A.

    1994-01-01

    Subchondral signal abnormalities are often present on magnetic resonance (MR) images of patients with osteoarthritis, but no study correlating these changes with histopathology has been published. We selected nine consecutive patients with clinical and radiographic diagnosis of moderate to severe osteoarthritis of the knee scheduled to under go joint replacement surgery, and performed MR imaging and conventional radiographs pre-operatively. After surgery, the resected portions of the femur and tibia underwent gross and microscopic examination, and the findings were correlated with the corresponding findings on the imaging studies. Subchondral MR signal abnormalities of the femur or tibia were present in seven of the nine patients, with intermediate signal on T1-weighted images and low or isointense signal on T2-weighted images. The subchondral signal abnormalities were hemispherical in configuration and corresponded predominantly to fibrous tissue replacing the fatty marrow. A component of trabecular thickening was also present. (orig.)

  8. Subchondral insufficiency fracture of the femoral head in a patient with alkaptonuria

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, Takahiro; Shida, Jun-ichi; Inokuchi, Akihiko; Arizono, Takeshi [Kyushu Central Hospital, Department of Orthopaedic Surgery, Fukuoka-city (Japan); Yamamoto, Takuaki [Kyushu University, Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Fukuoka-city (Japan)

    2014-06-15

    We report a patient with alkaptonuria accompanied by bilateral rapidly destructive arthrosis of the hip. The destruction of the left hip joint with its severe functional impairment necessitated total hip arthroplasty (THA). The outcome was satisfactory. Both magnetic resonance imaging (MRI) and pathologic findings were compatible with a subchondral insufficiency fracture. A year and half later, during a follow-up visit, the patient complained of right coxalgia. Radiography showed that the right femoral head had already disappeared, requiring THA of the right hip. Although there have been a few reports of rapid destructive hip osteoarthritis associated with ochronotic arthropathy, the pathogenesis of the destructive change is not clear. Subchondral insufficiency fracture was diagnosed on MR imaging and pathologically confirmed in our patient with alkaptonuria, suggesting that subchondral insufficiency fracture is one of the causes of ochronotic hip destruction. (orig.)

  9. Subchondral insufficiency fracture of the femoral head in a patient with alkaptonuria

    International Nuclear Information System (INIS)

    Hamada, Takahiro; Shida, Jun-ichi; Inokuchi, Akihiko; Arizono, Takeshi; Yamamoto, Takuaki

    2014-01-01

    We report a patient with alkaptonuria accompanied by bilateral rapidly destructive arthrosis of the hip. The destruction of the left hip joint with its severe functional impairment necessitated total hip arthroplasty (THA). The outcome was satisfactory. Both magnetic resonance imaging (MRI) and pathologic findings were compatible with a subchondral insufficiency fracture. A year and half later, during a follow-up visit, the patient complained of right coxalgia. Radiography showed that the right femoral head had already disappeared, requiring THA of the right hip. Although there have been a few reports of rapid destructive hip osteoarthritis associated with ochronotic arthropathy, the pathogenesis of the destructive change is not clear. Subchondral insufficiency fracture was diagnosed on MR imaging and pathologically confirmed in our patient with alkaptonuria, suggesting that subchondral insufficiency fracture is one of the causes of ochronotic hip destruction. (orig.)

  10. Subchondral insufficiency fracture of the femoral head in a patient with alkaptonuria.

    Science.gov (United States)

    Hamada, Takahiro; Yamamoto, Takuaki; Shida, Jun-ichi; Inokuchi, Akihiko; Arizono, Takeshi

    2014-06-01

    We report a patient with alkaptonuria accompanied by bilateral rapidly destructive arthrosis of the hip. The destruction of the left hip joint with its severe functional impairment necessitated total hip arthroplasty (THA). The outcome was satisfactory. Both magnetic resonance imaging (MRI) and pathologic findings were compatible with a subchondral insufficiency fracture. A year and half later, during a follow-up visit, the patient complained of right coxalgia. Radiography showed that the right femoral head had already disappeared, requiring THA of the right hip. Although there have been a few reports of rapid destructive hip osteoarthritis associated with ochronotic arthropathy, the pathogenesis of the destructive change is not clear. Subchondral insufficiency fracture was diagnosed on MR imaging and pathologically confirmed in our patient with alkaptonuria, suggesting that subchondral insufficiency fracture is one of the causes of ochronotic hip destruction.

  11. Weathering as the limiting factor of denudation in the Western escarpment of the Andes

    Science.gov (United States)

    Abbühl, L. M.; Schlunegger, F.; Kracht, O.; Ramseyer, K.; Rieke-Zapp, D.; Aldahan, A.; von Blanckenburg, F.

    2009-04-01

    A crucial issue in process geomorphology is the search for the scale and the extent to which precipitation, and climate in general, influences the nature and the rates of sediment transfer (weathering, erosion, sediment transport and deposition). We present an analysis of the possible interplay between precipitation, weathering and denudation rates for the western Andean slope between the Cordillera and the Pacific coast. It is based on morphometric studies and quantitative 10Be denudation rate estimates of three transverse river systems (Piura at 5°S, Pisco at 13°S, and Lluta at 18°S) draining the Western escarpment of the Peruvian and North Chilean Andes. The systems originate at elevations >3000 m above sea level, cover an area between 3000 and 10'000 km2 and discharge into the Pacific Ocean. The precipitation rate pattern implies a hyperarid climate at the coast, and semi-arid to semi-humid conditions in the Cordillera where the streams rise. There, climatic conditions are generally controlled by the easterlies that deliver moisture from the Atlantic Ocean via the low level Andean jet. The precipitation rate pattern of the Cordillera shows a North-South decreasing trend, from ca. 1000 mm/yr in Northern Peru to 150 mm/yr in Northern Chile. In these higher regions of the drainage basins, hillslopes are convex with nearly constant curvatures and are mantled by a >1 m thick regolith cover. In addition, hillslope erosion is limited to the regolith-bedrock interface. We interpret these geomorphic features to indicate weathering-controlled sediment discharge. In the lower river segments, beyond tectonic knickzones, regular precipitation is almost absent. For the case of the Piura river in Northern Peru, precipitation in this segment occurs in relation to highly episodic El Niño events related to the westerlies. This results in a supply-limited sediment discharge, leading to predominance of channelized processes on the hillslopes, a spare regolith cover and an

  12. Modes, tempo and spatial variability of Cenozoic cratonic denudation: morphoclimatic constraints from West Africa

    Science.gov (United States)

    Beauvais, Anicet; Chardon, Dominique

    2010-05-01

    After the onset of Gondwana break-up in the Early Mesozoic, the emerged part of the African plate underwent long Greenhouse effect climatic periods and epeirogeny. The last Greenhouse effect period in the Early Cenozoic and the alternation of wet and dry climatic periods since the Eocene enhanced episodes of rock chemical weathering and laterite production, forming bauxites and ferricretes, interrupted by drier periods of dominantly mechanical denudation, shaping glacis [1]. In Sub-Saharan West Africa, this evolution resulted in pulsate and essentially climatically-forced denudation that has shaped an ubiquitous sequence of five stepped lateritic paleosurfaces that synchronously developed over Cenozoic times. The modes, timing and spatial variability of continental denudation of the region are investigated by combining geomorphologic and geochronological data sets. The geomorphologic data set comprises the altitudinal distribution of the lateritic paleosurfaces relicts and their differential elevation from 42 locations in Sub-Saharan West Africa where the sequence (or part of it) has been documented. The geochronological data set consists in the age ranges of each paleosurface tackled by radiometric 39Ar-40Ar dating of the neoformed oxy-hydroxides (i.e., cryptomelane, K1-2Mn8O16, nH2O, [4]) carried by their laterites at the Tambao reference site, Burkina Faso [1, 3]. Five groups of 39Ar-40Ar ages, ~ 59 - 45 Ma, ~ 29 - 24 Ma, ~ 18 - 11.5 Ma, ~ 7.2 - 5.8 Ma, and ~ 3.4 - 2.9 Ma, characterize periods of chemical weathering whereas the time laps between these groups of ages correspond to episodes of mechanical denudation that reflect physical shaping of the paleosurfaces. For the last 45 Ma, the denudation rate estimates (3 to 8 m Ma-1) are comparable with those derived on shorter time scale (103 to 106 y.) in the same region by the cosmogenic radionuclide method [2]. Combined with the geomorphologic data set, these age ranges allow the visualization of the regional

  13. Tectono-denudation process of Nanxiong fault and its relations to uranium metallogenesis

    International Nuclear Information System (INIS)

    Chen Yuehui

    1994-01-01

    A large mylonite zone is distributed on the foot wall of Nanxiong fault, which is parallel to the fault. On the hanging wall, there is a Meso-Cenozoic basin. As sedimentation centers are moved towards the side of the fault, the strata become more younger. By investigation of the mylonite zone along the profile on the foot wall of the fault, the author studies in detail various kinds of ductile deformation fabrics in mylonite such as S-C fabrics, rotational porphyroclasts and stretching lineation etc. In the light of the kinematic direction of deformation fabrics, together with the characteristics of brittle tectonites in the fault and the distribution of normal faults in the basin, the author believes that Nanxiong fault is a big-size denudation fault. According to the formation and evolution of the denudation fault, its rock and ore-controlling roles, the relations between the fault and uranium metallogenesis are also preliminarily discussed

  14. Kinetically limited weathering at low denudation rates in semi-arid climates

    Science.gov (United States)

    Vanacker, V.; Schoonejans, J.; Opfergelt, S.; Ameijeiras-Marino, Y.; Christl, M.

    2016-12-01

    On Earth, the Critical Zone supports terrestrial life, being the near-surface environment where interactions between the atmosphere, lithosphere, hydrosphere, and biosphere take place Quantitative understanding of the interaction between mechanical rock breakdown, chemical weathering, and physical erosion is essential for unraveling Earth's biogeochemical cycles. In this study, we explore the role of soil water balance on regulating soil chemical weathering under water deficit regimes. Weathering rates and intensities were evaluated for nine soil profiles located on convex ridge crests of three mountain ranges in the Spanish Betic Cordillera. We present and compare quantitative information on soil weathering, chemical depletion and total denudation that were derived based on geochemical mass balance, 10Be cosmogenic nuclides and U-series disequilibria. Soil production rates determined based on U-series isotopes (238U, 234U, 230Th and 226Ra) are of the same order of magnitude as 10Be-derived denudation rates, suggesting steady state soil thickness, in two out of three sampling sites. The chemical weathering intensities are relatively low (˜5 to 30% of the total denudation of the soil) and negatively correlated with the magnitude of the water deficit in soils. Soil weathering extents increase (nonlinearly) with soil thickness and decrease with increasing surface denudation rates, consistent with kinetically limited or controlled weathering. Our study suggests that soil residence time and water availability limit weathering processes in semi-arid climates, which has not been validated previously with field data. An important implication of this finding is that climatic regimes may strongly regulate soil weathering by modulating soil solute fluxes.

  15. Wet effluent diffusion denuder technique and the determination of volatile organic compounds in air. II. Monoterpenes

    Czech Academy of Sciences Publication Activity Database

    Sklenská, Jana; Broškovičová, Anna; Večeřa, Zbyněk

    2002-01-01

    Roč. 973, 1-2 (2002), s. 211-216 ISSN 0021-9673 R&D Projects: GA ČR GA203/98/0943 Grant - others:SPSDII(XE) EV/02/11 Institutional research plan: CEZ:AV0Z4031919 Keywords : wet effluent denuder technique * volatile organic compounds * monoterpenes Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.098, year: 2002

  16. Application of wet effluent diffusion denuder for measurement of uptake coefficient of gaseous pollutants

    Czech Academy of Sciences Publication Activity Database

    Motyka, K.; Mikuška, Pavel; Večeřa, Zbyněk

    2011-01-01

    Roč. 84, č. 2 (2011), s. 519-523 ISSN 0039-9140 R&D Projects: GA MŽP SP/1A3/148/08; GA MŽP SP/1A3/55/08; GA MŽP SP/1B7/189/07 Institutional research plan: CEZ:AV0Z40310501 Keywords : collection efficiency * wet effluent diffusion denuder * uptake coefficient Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.794, year: 2011

  17. Total glucosides of paeony prevents juxta-articular bone loss in experimental arthritis

    OpenAIRE

    Wei, Chen Chao; You, Fan Tian; Mei, Li Yu; Jian, Sun; Qiang, Chen Yong

    2013-01-01

    Background Total glucosides of paeony (TGP) is a biologically active compound extracted from Paeony root. TGP has been used in rheumatoid arthritis therapy for many years. However, the mechanism by which TGP prevents bone loss has been less explored. Methods TGP was orally administered for 3?months to New Zealand rabbits with antigen-induced arthritis (AIA). Digital x-ray knee images and bone mineral density (BMD) measurements of the subchondral knee bone were performed before sacrifice. Chon...

  18. High-capacity NO2 denuder systems operated at various temperatures (298-473 K).

    Science.gov (United States)

    Wolf, Jan-Christoph; Niessner, Reinhard

    2012-12-01

    In this study, we investigated several coatings for high-temperature, high-capacity, and high-efficiency denuder-based NO(2) removal, with the scope to face the harsh conditions and requirements of automotive exhaust gas sampling. As first coating, we propose a potassium iodide (KI)/polyethylene glycol coating with a high removal efficiency (ε > 98%) for about 2 h and 50 ppm NO(2) at room temperature (298 K). At elevated temperatures (423 K), the initial capacity (100 ppmh) is decreased to 15 ppmh. Furthermore, this is the first proposal of the ionic liquid methyl-butyl-imidazolium iodide ([BMIm(+)][I(-)]) as denuder coating material. At room temperature, this ionic liquid exhibits far greater capacity (300 ppmh) and NO(2) removal efficiency (ε > 99.9%) than KI. Nevertheless, KI exhibits a slightly (~10%) higher capacity at elevated temperatures than [BMIm(+)][I(-)]. Both coatings presented are suitable for applications requiring selective denuding of NO(2) at temperatures up to 423 K.

  19. Field performance evaluation during fog-dominated wintertime of a newly developed denuder-equipped PM1 sampler.

    Science.gov (United States)

    Singh, Dharmendra Kumar; Lakshay; Gupta, Tarun

    2014-03-01

    This study presents the performance evaluation of a novel denuder-equipped PM1 (particles having aerodynamic diameter less than 1 μm) sampler, tested during fog-dominated wintertime, in the city of Kanpur, India. One PM1 sampler and one denuder-equipped PM1 sampler were co-located to collect ambient PM1 for 25 days. The mean PM1 mass concentration measured on foggy days with the PM1 sampler and the denuder-equipped PM1 sampler was found to be 165.95 and 135.48 μg/m(3), respectively. The mean PM1 mass concentration measured on clear days with the PM1 sampler and the denuder-equipped PM1 sampler was observed to be 159.66 and 125.14 μg/m(3), respectively. The mass concentration with denuder-fitted PM1 sampler for both foggy and clear days was always found less than the PM1 sampler. The same drift was observed in the concentrations of water-soluble ions and water-soluble organic carbon (WSOC). Moreover, it was observed that the use of denuder leads to a significant reduction in the PM positive artifact. The difference in the concentration of chemical species obtained by two samplers indicates that the PM1 sampler without denuder had overestimated the concentrations of chemical species in a worst-case scenario by almost 40 %. Denuder-fitted PM1 sampler can serve as a useful sampling tool in estimating the true values for nitrate, ammonium, potassium, sodium and WSOC present in the ambient PM.

  20. Catastrophic complication following injection and extracorporeal shock wave therapy of a medial femoral condyle subchondral cystic lesion in a 14 year old Arabian mare

    Directory of Open Access Journals (Sweden)

    Darla K. Moser

    2017-05-01

    Full Text Available This report describes fibrous cyst lining injection and extracorporeal shock wave therapy (ESWT of a medial femoral condyle (MFC subchondral cystic lesion (SCL resulting in catastrophic MFC fracture in an Arabian mare. The mare was presented for evaluation of a severe hind limb lameness of approximately 4 months duration. On presentation, a non-weight bearing lameness of the left hind limb with severe effusion and soft tissue swelling of the stifle region was noted. Radiographic evaluation of the stifle revealed a large SCL of the MFC with associated osteoarthritis. Arthroscopic guided intra-lesional injection of the SCL with corticosteroids and autologous bone marrow concentrate was performed followed by ESWT of the MFC. The mare was discharged walking comfortably 48-hours post-operatively. An acute increase in lameness was noted 14 days post-operatively. Imaging revealed catastrophic fracture of the left MFC. Possible mechanisms leading to failure of the MFC secondary to the described treatment are discussed.

  1. Common site of subchondral insufficiency fractures of the femoral head based on three-dimensional magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Iwasaki, Kenyu; Yamamoto, Takuaki; Motomura, Goro; Karasuyama, Kazuyuki; Sonoda, Kazuhiko; Kubo, Yusuke; Iwamoto, Yukihide [Kyushu University, Department of Orthopaedic Surgery Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan)

    2016-01-15

    The objective of this study was to investigate the common sites of subchondral insufficiency fractures of the femoral head (SIF) based on three-dimensional (3-D) reconstruction of MR images. In 33 hips of 31 consecutive patients diagnosed with SIF, 3-D reconstruction of the bone, fracture, and acetabular edge was performed using MR images. These 3-D images were used to measure the fractured areas and clarify the positional relationship between the fracture and degree of acetabular coverage. The fractured area in the anterior portion was significantly larger than in the posterior area. In 11 cases, the fractures contacted the acetabular edge and were distributed on the lateral portion. The indices of acetabular coverage (center-edge angle and acetabular head index) in these cases were less than the normal range. In the remaining 22 cases, the fractures were apart from the acetabular edge and distributed on the mediolateral centerline of the femoral head. The majority of these cases had normal acetabular coverage. The common site of SIF is the anterior portion. In addition, two types of SIF are proposed: (1) Lateral type: the contact stress between the acetabular edge and lateral portion of the femoral head causes SIF based on the insufficient acetabular coverage, and (2) Central type: the contact stress between the acetabular surface and the mediolateral center of the femoral head causes SIF independent from the insufficiency of acetabular coverage. These findings may be useful for considering the treatment and prevention of SIF. (orig.)

  2. Volar plating for distal radius fractures--do not trust the image intensifier when judging distal subchondral screw length.

    Science.gov (United States)

    Park, Derek H; Goldie, Boyd S

    2012-09-01

    The use of the volar plate to treat distal radius fractures is increasing but despite the theoretical advantages of a volar approach there have been reports of extensor tendon ruptures due to prominent screw tips protruding past the dorsal cortex. The valley in the intermediate column between Lister tubercle and the sigmoid notch of the distal radius makes it difficult to rely on fluoroscopy to judge screw length. Our aim was to quantify the dimensions of this valley and to demonstrate the danger of relying on intraoperative image intensification fluoroscopy to determine lengths of distal screws. We measured the depth of this valley in the intermediate column of the distal radius in 33 patients with computed tomographic (9 patients) or magnetic resonance image (24 patients) scans of the wrist. There was a consistent valley in all images examined [average 1.8 mm (95% confidence interval, 1.6-2.0 mm)]. Thirty-nine percent of wrists had a valley depth of at least 2 mm. Standard lateral views or rotation of the forearm to obtain oblique views does not identify prominent screw tips; and whatever the rotation of the forearm, screw tips protruding beyond dorsal cortex may look as if it is within the bone when in fact it is out. When drilling we suggest noting the depth at which the drill bit just penetrates dorsal cortex and routinely downsize the distal screw length by 2 mm. We caution against relying on flourosocopy when judging the length of the distal subchondral screws.

  3. Paragenesis of thermal denudation with gas-emission crater and lake formation, Yamal Peninsula, Russia

    Science.gov (United States)

    Babkina, Elena; Khomutov, Artem; Leibman, Marina; Dvornikov, Yury; Kizyakov, Alexander; Babkin, Evgeny

    2017-04-01

    Gas-emission craters (GECs) found in the North of West Siberia in 2014 occur in an area of wide tabular ground ice (TGI) distribution. TGI observed in the GEC walls also provokes thermal denudation: a complex of processes responsible for formation of thermocirques (TCs). TCs are semi-circle shaped depressions resulting from TGI thaw and removal of detached material downslope. Shores of many lakes are terraced and have ancient to recent traces of thermal denudation activity. TCs are numerous in the GEC area giving reason to assume that GEC, TGI, TC, and lakes are interrelated. First found Yamal crater (GEC-1) expanded from initial 18 m wide deep hole in 2013 to an irregularly-shaped lake up to 85 meters wide in 2016. Expansion of the GEC was controlled by TGI thaw. This can be considered in terms of thermal denudation and analyzed on the basis of TC study in the adjacent area. In summer 2014 and 2015 (the lifetime of the GEC-1) its wall retreat covered the area of 1730 square meters, which gives 865 square meters per year. In 2016, which was the warmest for the period of observation at weather station Marre-Sale, retreat area increased to 2200 square meters per year. TC, which exposed TGI similar to that in the walls of GEC-1, is observed on the nearest lakeshore. TC activation probably started in 2012 as elsewhere on Yamal. In 2015 its area according to GPS survey reached 4400 square meters (a four-year average 1100 square meters). Since September 2015 and till October 2016 its area expanded by 2600 square meters, thus increased by 59%, and more than twice compared to previous annual average. Lake adjacent to GEC-1 in 2016 was separated from crater edge by only a 13 meter wide isthmus, most likely both GEC-1 lake and adjacent lake merge in few years. Therefore, single basis of erosion for thermal denudation appear. After lakes merge, it would become hard to determine what the initial process for the lake formation was if not for the occasional discovery of the GEC

  4. Improved cartilage regeneration by implantation of acellular biomaterials after bone marrow stimulation: a systematic review and meta-analysis of animal studies

    NARCIS (Netherlands)

    Pot, M.W.; Gonzales, V.K.; Buma, P.; Hout, J. in't; Kuppevelt, T.H. van; Vries, R.B. de; Daamen, W.F.

    2016-01-01

    Microfracture surgery may be applied to treat cartilage defects. During the procedure the subchondral bone is penetrated, allowing bone marrow-derived mesenchymal stem cells to migrate towards the defect site and form new cartilage tissue. Microfracture surgery generally results in the formation of

  5. Bone marrow oedema on MR imaging indicates ARCO stage 3 disease in patients with AVN of the femoral head.

    Science.gov (United States)

    Meier, Reinhard; Kraus, Tobias M; Schaeffeler, Christoph; Torka, Sebastian; Schlitter, Anna Melissa; Specht, Katja; Haller, Bernhard; Waldt, Simone; Rechl, Hans; Rummeny, Ernst J; Woertler, Klaus

    2014-09-01

    To test the hypothesis that bone marrow oedema (BME) observed on MRI in patients with avascular necrosis (AVN) of the femoral head represents an indicator of subchondral fracture. Thirty-seven symptomatic hips of 27 consecutive patients (53% women, mean age 49.2) with AVN of the femoral head and associated BME on magnetic resonance (MR) imaging were included. MR findings were correlated with computed tomography (CT) of the hip and confirmed by histopathological examination of the resected femoral head. Imaging studies were analysed by two radiologists with use of the ARCO classification. On MR imaging a fracture line could be identified in 19/37 (51%) cases, which were classified as ARCO stage 3 (n = 15) and stage 4 (n = 4). The remaining 18/37 (49%) cases were classified as ARCO stage 2. However, in all 37/37 (100%) cases a subchondral fracture was identified on CT, indicating ARCO stage 3/4 disease. The extent of subchondral fractures and the femoral head collapse was graded higher on CT as compared to MRI (P AVN, BME of the femoral head represents a secondary sign of subchondral fracture and thus indicates ARCO stage 3 disease. BME on MRI in AVN of femoral head indicates a subchondral fracture. BME in AVN of the femoral head represents ARCO stage 3/4 disease. CT identifies subchondral fractures and femoral head collapse better than MR imaging. This knowledge helps to avoid understaging and to trigger adequate treatment.

  6. The role of computed tomography in evaluation of subchondral osseous lesions in seven horses with chronic synovitis

    International Nuclear Information System (INIS)

    Hanson, J.A.; Seeherman, H.J.; Kirker-Head, C.A.; O'Callaghan, M.W.

    1996-01-01

    Seven horses with severe, persistent lameness of sudden onset were evaluated with scintigraphy and/or computed tomography. The lameness was localised to the front fetlock joint in 2 horses and to the tibiotarsal joint in 5 horses. Five of the horses had a history of intra-articular injections of the involved joint prior to presentation. All horses had effusion of the affected joint and were positive to flexion tests. Intraarticular anaesthesia eliminated or improved the lameness in 4 cases and a nerve conduction block proximal to the affected joint improved the lameness in another. Cytology examination of fluid from affected joints identified normal joint fluid (one horse) or elevations in nucleated cell counts of 0.9 x 10(9)/l-36.8 x 10(9)/l and total protein 20-42 g/l (6 horses). The joint fluid of 2 of these horses cultured positive for bacteria. Initial radiographs were either normal (4 cases) or the changes seen were not sufficient to explain the degree of lameness. In the 6 cases where scintigraphy was performed, intense focal isotope uptake was found in the suspected region, which corresponded to the proximal portion of the first phalanx (2 cases), distal tibia (2 cases), or talus (3 cases). Computed tomography (CT) was performed because occult fracture or osteomyelitis was suspected; and knowledge of the precise anatomical location of the lesion was considered necessary to assess the need for surgery and to plan the surgical approach. Hypodense focal lesions with hyperdense haloes were found in the subchondral bone deep to the sagittal groove of the first phalanx (P1) (2 cases) in the cochlea of the distal tibia (2 cases), and in the intertrochlear portion of the talus (3 cases). Communication between the lesion and the joint space was demonstrated by CT in 5 cases. Post mortem examination of one case revealed synovitis and a chronic bone abscess (Brodie's abscess) communicating with the joint space

  7. Microstructural changes in cartilage and bone related to repetitive overloading in an equine athlete model.

    Science.gov (United States)

    Turley, Sean M; Thambyah, Ashvin; Riggs, Christopher M; Firth, Elwyn C; Broom, Neil D

    2014-06-01

    The palmar aspect of the third metacarpal (MC3) condyle of equine athletes is known to be subjected to repetitive overloading that can lead to the accumulation of joint tissue damage, degeneration, and stress fractures, some of which result in catastrophic failure. However, there is still a need to understand at a detailed microstructural level how this damage progresses in the context of the wider joint tissue complex, i.e. the articular surface, the hyaline and calcified cartilage, and the subchondral bone. MC3 bones from non-fractured joints were obtained from the right forelimbs of 16 Thoroughbred racehorses varying in age between 3 and 8 years, with documented histories of active race training. Detailed microstructural analysis of two clinically important sites, the parasagittal grooves and the mid-condylar regions, identified extensive levels of microdamage in the calcified cartilage and subchondral bone concealed beneath outwardly intact hyaline cartilage. The study shows a progression in microdamage severity, commencing with mild hard-tissue microcracking in younger animals and escalating to severe subchondral bone collapse and lesion formation in the hyaline cartilage with increasing age and thus athletic activity. The presence of a clearly distinguishable fibrous tissue layer at the articular surface immediately above sites of severe subchondral collapse suggested a limited reparative response in the hyaline cartilage. © 2014 Anatomical Society.

  8. Microstructural changes in cartilage and bone related to repetitive overloading in an equine athlete model

    Science.gov (United States)

    Turley, Sean M; Thambyah, Ashvin; Riggs, Christopher M; Firth, Elwyn C; Broom, Neil D

    2014-01-01

    The palmar aspect of the third metacarpal (MC3) condyle of equine athletes is known to be subjected to repetitive overloading that can lead to the accumulation of joint tissue damage, degeneration, and stress fractures, some of which result in catastrophic failure. However, there is still a need to understand at a detailed microstructural level how this damage progresses in the context of the wider joint tissue complex, i.e. the articular surface, the hyaline and calcified cartilage, and the subchondral bone. MC3 bones from non-fractured joints were obtained from the right forelimbs of 16 Thoroughbred racehorses varying in age between 3 and 8 years, with documented histories of active race training. Detailed microstructural analysis of two clinically important sites, the parasagittal grooves and the mid-condylar regions, identified extensive levels of microdamage in the calcified cartilage and subchondral bone concealed beneath outwardly intact hyaline cartilage. The study shows a progression in microdamage severity, commencing with mild hard-tissue microcracking in younger animals and escalating to severe subchondral bone collapse and lesion formation in the hyaline cartilage with increasing age and thus athletic activity. The presence of a clearly distinguishable fibrous tissue layer at the articular surface immediately above sites of severe subchondral collapse suggested a limited reparative response in the hyaline cartilage. PMID:24689513

  9. Repair of articular cartilage and subchondral defects in rabbit knee joints with a polyvinyl alcohol/nano-hydroxyapatite/polyamide 66 biological composite material.

    Science.gov (United States)

    Guo, Tao; Tian, Xiaobin; Li, Bo; Yang, Tianfu; Li, Yubao

    2017-11-15

    This study sought to prepare a new PVA/n-HA/PA66 composite to investigate the repair of articular cartilage and subchondral defects in rabbit knee joints. A 5 × 5 × 5 mm-sized defect was created in the patellofemoral joints of 72 healthy adult New Zealand rabbits. The rabbits were then randomly divided into three groups (n = 24): PVA/n-HA+PA66 group, polyvinyl alcohol (PVA) group, and control (untreated) group. Cylindrical PVA/n-HA+PA66, 5 × 5 mm, comprised an upper PVA layer and a lower n-HA+PA66 layer. Macroscopic and histological evaluations were performed at 4, 8, 12, and 24 weeks, postoperatively. Type II collagen was measured by immunohistochemical staining. The implant/cartilage and bone interfaces were observed by scanning electron microscopy. At 24 weeks postoperatively, the lower PVA/n-HA+PA66 layer became surrounded by cartilage, with no obvious degeneration. In the PVA group, an enlarged space was observed between the implant and the host tissue that had undergone degeneration. In the control group, the articular cartilage had become calcified. In the PVA/n-HA+PA66 group, positive type II collagen staining was observed between the composite and the surrounding cartilage and on the implant surface. In the PVA group, positive staining was slightly increased between the PVA and the surrounding cartilage, but reduced on the PVA surface. In the control group, reduced staining was observed throughout. Scanning electron microscopy showed increased bone tissue in the lower n-HA+PA66 layer that was in close approximation with the upper PVA layer of the composite. In the PVA group, the bone tissue around the material had receded, and in the control group, the defect was filled with bone tissue, while the superior aspect of the defect was filled with disordered, fibrous tissue. The diphase biological composite material PVA/n-HA+PA66 exhibits good histocompatibility and offers a satisfactory substitute for articular cartilage and subchondral bone.

  10. Do cartilage and subchondral bone act together in development and disease?

    NARCIS (Netherlands)

    Harst, Mark Robert van der

    2005-01-01

    The principal goal of this work was to test the hypothesis that the joint should not be viewed as a composite structure consisting of a number of different and distinct connective tissue layers, but rather as an “organ” that is made up of functionally related tissues that share many characteristics

  11. The initial bearing capacities of subchondral bone replacements considerably contributing to chondrogenesis

    Czech Academy of Sciences Publication Activity Database

    Petrtýl, M.; Danešová, J.; Lísal, J.; Šenolt, L.; Hulejová, H.; Polanská, M.; Bastl, Zdeněk; Kruliš, Zdeněk; Černý, P.

    2010-01-01

    Roč. 12, č. 3 (2010), s. 59-65 ISSN 1509-409X R&D Projects: GA ČR GA106/06/0761 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z40500505 Keywords : biomechanics * osteochondral defects * polymer replacement Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.432, year: 2010

  12. Antioxidants attenuate atherosclerotic plaque development in a balloon-denuded and -radiated hypercholesterolemic rabbit

    International Nuclear Information System (INIS)

    Leborgne, Laurent; Fournadjiev, Jana; Pakala, Rajbabu; Dilcher, Christian; Cheneau, Edouard; Wolfram, Roswitha; Hellinga, David; Seaborn, Rufus; O'Tio, Fermin; Waksman, Ron

    2003-01-01

    Background: Oxidation of lipoproteins is considered to be a key contributor to atherogenesis. Antioxidants are potential antiatherogenic agents because they can inhibit lipoprotein oxidation. Radiation has been shown to increase oxidative stress leading to increased atherogenesis. This study is designed to test the potential of antioxidants to inhibit atherosclerotic plaque progression in balloon-denuded and -radiated rabbits. Methods and Results: Two groups of New Zealand white rabbits (n=36) were fed with 1% cholesterol diet (control diet) or with 1% cholesterol diet containing a mixture of various antioxidants for 1 week. Iliac arteries in all the animals were balloon denuded and continued to fed with 0.15% cholesterol diet or 0.15% cholesterol diet containing antioxidants (antioxidant diet). Four weeks after balloon denudation one iliac artery in 12 animals from each group was radiated and all the animals were continued to be fed with the same diet. Four weeks after radiation animals were sacrificed and morphometric analysis of iliac arteries (n=12) in nonradiated and radiated animals were performed. Plaque area (PA) in the rabbits that were fed with cholesterol diet is 0.2±0.12 mm 2 , and it is increased by 2.75-fold (P<.05) in the radiated arteries of animals fed with cholesterol diet. Plaque area in the animals fed with antioxidant diet is 50% less then the one in the animals fed with cholesterol diet. Similarly, plaque area in radiated arteries of the animals fed with antioxidant diet is 50% less then the animals fed with cholesterol diet. Conclusion: Antioxidants significantly attenuate atherosclerotic plaque progression in balloon-injured and -radiated hypercholesterolemic rabbits

  13. Automated assessment of bone changes in cross-sectional micro-CT studies of murine experimental osteoarthritis

    OpenAIRE

    Das Neves Borges, P; Vincent, TL; Marenzana, M; Espinoza Orías, AA

    2017-01-01

    OBJECTIVE: The degradation of articular cartilage, which characterises osteoarthritis (OA), is usually paired with excessive bone remodelling, including subchondral bone sclerosis, cysts, and osteophyte formation. Experimental models of OA are widely used to investigate pathogenesis, yet few validated methodologies for assessing periarticular bone morphology exist and quantitative measurements are limited by manual segmentation of micro-CT scans. The aim of this work was to chart the temporal...

  14. New approach to resolve the amount of Quaternary uplift and associated denudation of the mountain ranges in the Japanese Islands

    Directory of Open Access Journals (Sweden)

    Shigeru Sueoka

    2016-03-01

    Full Text Available Low-temperature thermochronology is a widely used tool for revealing denudation histories of mountain ranges. Although this technique has been applied mainly to continental orogens, such as the European Alps, Himalayas, and Andes, recent technological development of low-temperature thermochronology has made it applicable to a wider variety of mountain ranges with various sizes and tectonic histories. The Japanese Islands comprise young and active island arcs, where an early stage of mountain range formation is observed. Numerous attempts have been made to constrain the uplift and denudation histories of the mountains in the Japanese Islands using geologic, geomorphologic, or geodetic methods. However, the number of thermochronometric attempts has been limited primarily due to the small amount of total denudation since the initiation of the uplift. In this review paper, we introduce the tectonic and geomorphic settings of the mountain ranges in the Japanese Islands, and discuss previous attempts to estimate uplift or denudation of the Japanese mountains using methods other than thermochronology. Furthermore, we discuss problems of the thermochronometric applications in revealing denudation histories of the Japanese mountains. Finally, we present a case study of the Kiso Range in central Japan and discuss the current effectiveness and applicability of low-temperature thermochronology to the Japanese mountainous areas.

  15. Comparison of gaseous oxidized Hg measured by KCl-coated denuders, and nylon and cation exchange membranes.

    Science.gov (United States)

    Huang, Jiaoyan; Miller, Matthieu B; Weiss-Penzias, Peter; Gustin, Mae Sexauer

    2013-07-02

    The chemical compounds that make up gaseous oxidized mercury (GOM) in the atmosphere, and the reactions responsible for their formation, are not well understood. The limitations and uncertainties associated with the current method applied to measure these compounds, the KCl-coated denuder, are not known due to lack of calibration and testing. This study systematically compared the uptake of specific GOM compounds by KCl-coated denuders with that collected using nylon and cation exchange membranes in the laboratory and field. In addition, a new method for identifying different GOM compounds using thermal desorption is presented. Different GOM compounds (HgCl2, HgBr2, and HgO) were found to have different affinities for the denuder surface and the denuder underestimated each of these compounds. Membranes measured 1.3 to 3.7 times higher GOM than denuders in laboratory and field experiments. Cation exchange membranes had the highest collection efficiency. Thermodesorption profiles for the release of GOM compounds from the nylon membrane were different for HgO versus HgBr2 and HgCl2. Application of the new field method for collection and identification of GOM compounds demonstrated these vary as a function of location and time of year. Understanding the chemistry of GOM across space and time has important implications for those developing policy regarding this environmental contaminant.

  16. Subchondral cysts of the atlantoaxial joint: a risk factor for odontoid fractures in the elderly.

    Science.gov (United States)

    Julien, Terrill P; Schoenfeld, Andrew J; Barlow, Brian; Harris, Mitchel B

    2009-10-01

    Scholars have postulated that cervical degeneration can predispose the upper cervical spine to injury after minor trauma. Subchondral cysts have previously been recognized as potentiators of fracture in the hip and knee but no cases of cervical degenerative cysts contributing to fracture have been reported. This report documents a case series in which patients sustained significant injury to the upper cervical spine in the setting of subchondral cervical cysts. Case series/academic level I trauma center. Between 2004 and 2008, six patients (ages 73-91 years) with cervical pathology were admitted to the trauma service at our Level I trauma center. The most common mechanism of injury was a low velocity fall, which occurred in 5 out of 6 patients. All patients suffered an odontoid fracture. In all cases, there was radiographic evidence of cyst formation, and computed tomographic imaging demonstrated fracture communication with the subchondral cyst. Of the six cases, four were treated definitively with immobilization in a cervical orthosis and two required surgery. One patient was treated with an occipital-cervical fusion, whereas the other underwent Brooks wiring. All patients ultimately went on to heal their fractures. Degenerative changes in the cervical spine have previously been recognized to potentiate injury. This report raises the question of whether degenerative processes at the C1-C2 articulation predispose elderly patients to injury at this level. The presence of cystic degeneration at the atlantoaxial joint should be recognized as a potential risk factor for cervical injury after relatively minor trauma.

  17. Imaging and histopathological evaluation of a cystlike formation in subchondral insufficiency fracture of the femoral head: A case report and literature review.

    Science.gov (United States)

    Fukui, Kiyokazu; Kaneuji, Ayumi; Fukushima, Mana; Matsumoto, Tadami

    2014-01-01

    In the majority of subchondral insufficiency fractures (SIFs) of the femoral head, T1-weighted magnetic resonance imaging shows an irregular, serpiginous, low-intensity band that is convex to the articular surface. We report a case of a cystlike formation in SIF of the femoral head in an elderly woman. A 71-year-old woman reported right hip pain without any history of antecedent trauma. The initial radiograph showed a slight narrowing of the joint space in the right hip. The patient was treated with conservative therapy for 2 months. Radiographs obtained 3 months after the onset of pain showed non-progressive joint-space narrowing. T1-weighted magnetic resonance images obtained 2 months after pain onset revealed a round, cystlike, low-intensity area just beneath the articular cartilage. The patient underwent total hip arthroplasty. Histopathological examination showed fracture callus and granulation tissue in the subchondral area, surrounded by vascular-rich granulation tissue and fibrous tissue, which corresponded to the round, low-intensity band observed on the T1-weighted image. This case was a rare SIF of the femoral head which had a cystlike formation with a low signal intensity on T1-weighted images and a very high signal intensity on STIR sequences in the superolateral portion of the femoral head, surrounded by a pattern of edema in the bone marrow. To our knowledge, no similar cases were cited in the literature. It is important for surgeons to keep in mind that sometimes SIFs of the femoral head can appear as a round cystlike formation. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Luminescence of quartz and feldspar fingerprints provenance and correlates with the source area denudation in the Amazon River basin

    DEFF Research Database (Denmark)

    Sawakuchi, A.O.; Jain, M.; Mineli, T.D.

    2018-01-01

    The Amazon region hosts the world's largest watershed spanning from high elevation Andean terrains to lowland cratonic shield areas in tropical South America. This study explores variations in optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL) signals in suspended...... silt and riverbed sands retrieved from major Amazon rivers. These rivers drain Pre-Cambrian to Cenozoic source rocks in areas with contrasting denudation rates. In contrast to the previous studies, we do not observe an increase in the OSL sensitivity of quartz with transport distance; for example...... shield areas (denudation rate ξ=0.04 mmyr−1), while low sensitivity quartz occurs in less stable Andean terrains (ξ=0.24 mmyr−1). An apparent linear correlation between quartz OSL sensitivity and denudation rate suggests that OSL sensitivity may be used as a proxy for erosion rates in the Amazon basin...

  19. Bone fatigue and its implications for injuries in racehorses.

    Science.gov (United States)

    Martig, S; Chen, W; Lee, P V S; Whitton, R C

    2014-07-01

    Musculoskeletal injuries are a common cause of lost training days and wastage in racehorses. Many bone injuries are a consequence of repeated high loading during fast work, resulting in chronic damage accumulation and material fatigue of bone. The highest joint loads occur in the fetlock, which is also the most common site of subchondral bone injury in racehorses. Microcracks in the subchondral bone at sites where intra-articular fractures and palmar osteochondral disease occur are similar to the fatigue damage detected experimentally after repeated loading of bone. Fatigue is a process that has undergone much study in material science in order to avoid catastrophic failure of engineering structures. The term 'fatigue life' refers to the numbers of cycles of loading that can be sustained before failure occurs. Fatigue life decreases exponentially with increasing load. This is important in horses as loads within the limb increase with increasing speed. Bone adapts to increased loading by modelling to maintain the strains within the bone at a safe level. Bone also repairs fatigued matrix through remodelling. Fatigue injuries develop when microdamage accumulates faster than remodelling can repair. Remodelling of the equine metacarpus is reduced during race training and accelerated during rest periods. The first phase of remodelling is bone resorption, which weakens the bone through increased porosity. A bone that is porous following a rest period may fail earlier than a fully adapted bone. Maximising bone adaptation is an important part of training young racehorses. However, even well-adapted bones accumulate microdamage and require ongoing remodelling. If remodelling inhibition at the extremes of training is unavoidable then the duration of exposure to high-speed work needs to be limited and appropriate rest periods instituted. Further research is warranted to elucidate the effect of fast-speed work and rest on bone damage accumulation and repair. © 2014 EVJ Ltd.

  20. [Chemical denudation rates and carbon dioxide sink in Koxkar glacierised region at the south slope of Mt. Tianshan, China].

    Science.gov (United States)

    Wang, Jian; Xu, Jun-li; Zhang, Shi-qiang; Liu, Shi-yin; Han, Hai-dong

    2010-04-01

    Chemical denudation rates and carbon dioxide sink were from water samples from ice-melt water, precipitation and river water were collected daily from June 21st to September 10th in 2004 in the Koxkar glacier region, south slope of Mt. Tianshan, China. The law of conservation of mass was applied for calculating chemical denudation fluxes and transient carbon dioxide sink. It is found that: 1) There were average of 60.7 kg x (km2 x d)(-1) and 60.2 kg x (km2 x d)(-1) solutes supplied by precipitation and ice melt-water respectively which accounted for about 7.7% and 7.6% of the total solutes of bulk river water [791.2 kg x (km2 x d)(-1)]. Consequently, the rate of chemical denudation derived from the crustal flux was 558.0 kg x (km2 x d)(-1), accounting for 70.5%. 2) Carbonation weathering was 308.9 kg x (km2 x d)(-1), and heavier than that of the other chemical denudations. The crustal concentration of bicarbonates (HCO3-) is attributed chiefly to the carbonation of carbonates (limestone and dolomite) and aluminosilicates/silicates. A further important source of bicarbonates and sulphates is pyrite oxidation coupled with limestone/dolomite dissolution. The transient carbon dioxide sink can be estimated by ion balance law, which is 81.0 kg x (km2 x d)(-1), accounting for 14.2%. 3) The chemical denudation rates was 641.1 kg x (km2 x d)(-1) with relationship of specific conductivity to concentrations of dissolved carbonate in water, which is only 4.4% less than that obtained from mass balance method without regard to carbon dioxide sink. The study also implied important to evaluate chemical denudation fluxes of poor data in western mountain area, China. However, because of without chemical analysis and ion partitioning, the transient CO2 drawdown cannot be established.

  1. Enlarging bilateral femoral condylar bone cysts without scintigraphic uptake in a yearling foal

    International Nuclear Information System (INIS)

    Squire, K.R.E.; Fessler, J.F.; Cantwell, H.D.; Widmer, W.R.

    1992-01-01

    Bilateral subchondral bone cysts of the femoral condyles were diagnosed by conventional radiography in a 14 month old Appaloosa colt. Surgical debridement was performed, and over the next 18 months the appearance of the cysts was evaluated with radiography and bone scintigraphy. On the preoperative scintigrams, increased radiopharmaceutical uptake was associated with the cysts. Despite continued radiographic enlargement, the cysts did not demonstrate increased radiopharmaceutical uptake post-operatively

  2. A continuous-flow denuder for the measurement of ambient concentrations and surface-exchange fluxes of ammonia

    Science.gov (United States)

    Wyers, G. P.; Otjes, R. P.; Slanina, J.

    A new diffusion denuder is described for the continuous measurement of atmospheric ammonia. Ammonia is collected in an absorption solution in a rotating denuder, separated from interfering compounds by diffusion through a semi-permeable membrane and detected by conductometry. The method is free from interferences by other atmospheric gases, with the exception of volatile amines. The detection limit is 6 ng m -3 for a 30-min integration time. This compact instrument is fully automated and suited for routine deployment in field studies. The precision is sufficiently high for micrometeorological studies of air-surface exchange of ammonia.

  3. Rehabilitation and Return-to-Sports Activity after Debridement and Bone Marrow Stimulation of Osteochondral Talar Defects

    NARCIS (Netherlands)

    van Eekeren, Inge C. M.; Reilingh, Mikel L.; van Dijk, C. Niek

    2012-01-01

    An osteochondral defect (OD) is a lesion involving the articular cartilage and the underlying subchondral bone. ODs of the talus can severely impact on the quality of life of patients, who are usually young and athletic. The primary treatment for ODs that are too small for fixation, consists of

  4. Automated assessment of bone changes in cross-sectional micro-CT studies of murine experimental osteoarthritis.

    Science.gov (United States)

    Das Neves Borges, Patricia; Vincent, Tonia L; Marenzana, Massimo

    2017-01-01

    The degradation of articular cartilage, which characterises osteoarthritis (OA), is usually paired with excessive bone remodelling, including subchondral bone sclerosis, cysts, and osteophyte formation. Experimental models of OA are widely used to investigate pathogenesis, yet few validated methodologies for assessing periarticular bone morphology exist and quantitative measurements are limited by manual segmentation of micro-CT scans. The aim of this work was to chart the temporal changes in periarticular bone in murine OA by novel, automated micro-CT methods. OA was induced by destabilisation of the medial meniscus (DMM) in 10-week old male mice and disease assessed cross-sectionally from 1- to 20-weeks post-surgery. A novel approach was developed to automatically segment subchondral bone compartments into plate and trabecular bone in micro-CT scans of tibial epiphyses. Osteophyte volume, as assessed by shape differences using 3D image registration, and by measuring total epiphyseal volume was performed. Significant linear and volumetric structural modifications in subchondral bone compartments and osteophytes were measured from 4-weeks post-surgery and showed progressive changes at all time points; by 20 weeks, medial subchondral bone plate thickness increased by 160±19.5 μm and the medial osteophyte grew by 0.124±0.028 μm3. Excellent agreement was found when automated measurements were compared with manual assessments. Our automated methods for assessing bone changes in murine periarticular bone are rapid, quantitative, and highly accurate, and promise to be a useful tool in future preclinical studies of OA progression and treatment. The current approaches were developed specifically for cross-sectional micro-CT studies but could be applied to longitudinal studies.

  5. Automated assessment of bone changes in cross-sectional micro-CT studies of murine experimental osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Patricia Das Neves Borges

    Full Text Available The degradation of articular cartilage, which characterises osteoarthritis (OA, is usually paired with excessive bone remodelling, including subchondral bone sclerosis, cysts, and osteophyte formation. Experimental models of OA are widely used to investigate pathogenesis, yet few validated methodologies for assessing periarticular bone morphology exist and quantitative measurements are limited by manual segmentation of micro-CT scans. The aim of this work was to chart the temporal changes in periarticular bone in murine OA by novel, automated micro-CT methods.OA was induced by destabilisation of the medial meniscus (DMM in 10-week old male mice and disease assessed cross-sectionally from 1- to 20-weeks post-surgery. A novel approach was developed to automatically segment subchondral bone compartments into plate and trabecular bone in micro-CT scans of tibial epiphyses. Osteophyte volume, as assessed by shape differences using 3D image registration, and by measuring total epiphyseal volume was performed.Significant linear and volumetric structural modifications in subchondral bone compartments and osteophytes were measured from 4-weeks post-surgery and showed progressive changes at all time points; by 20 weeks, medial subchondral bone plate thickness increased by 160±19.5 μm and the medial osteophyte grew by 0.124±0.028 μm3. Excellent agreement was found when automated measurements were compared with manual assessments.Our automated methods for assessing bone changes in murine periarticular bone are rapid, quantitative, and highly accurate, and promise to be a useful tool in future preclinical studies of OA progression and treatment. The current approaches were developed specifically for cross-sectional micro-CT studies but could be applied to longitudinal studies.

  6. Current denudation rates in dolostone karst from central Spain: Implications for the formation of unroofed caves

    Science.gov (United States)

    Krklec, Kristina; Domínguez-Villar, David; Carrasco, Rosa M.; Pedraza, Javier

    2016-07-01

    Rock tablets of known weight were buried in the soil of a karst region in Central Spain to evaluate the carbonate weathering during a period of a year. The experiment was conducted at two different soil depths: 5-10 and 50-55 cm from the surface. The parental rock used in the experiment is composed of dolomite and magnesite with variable proportion of accessory minerals and minor elements. Soil mineral and chemical composition as well as its texture was also characterized. Meteorological conditions at the site together with temperature and CO2 in both soil levels were monitored. Sets of tablets were retrieved after 6 and 12 months of the start of the experiment to account for seasonal weathering. Different lithologies do not exhibit significant differences in weathering, although a large inter-sample variability is attributed to variable size and distribution of the porosity. Results show an enhanced weathering during the wet and cold season that accounts for 78 ± 1% of the total annual weathering. Rock tablets examined under scanning electron microscopy prior and after exposure to natural environment show that most of the material lost occurred along cracks, edges or large pores. Although dissolution is a common process, most of the weathering is due to crystal detachment. Rock tablets at the depth of 5-10 cm were weathered 68 ± 1% more than those set at 50-55 cm from the surface. Higher soil moisture and concentration of CO2 were found deeper in the soil, which likely enhanced the dissolution of carbonate. However, physical weathering dominated weight loss of rock tablets at both soil depths; especially at the 5-10 cm level where soil thermal and moisture cycles were more frequent and greater. Denudation rate calculated from the 12 months set provides values of 2.48 ± 1.07 μm/yr and 1.75 ± 0.66 μm/yr at the depths of 5-10 and 50-55 cm, respectively. Since the conditions at the average contact between soil and bedrock are similar to those at the 50-55 cm

  7. Geoprospective study of a nuclear waste repository. Process of erosion and denudation

    International Nuclear Information System (INIS)

    Laville, P.; Lajoinie, J.P.

    1985-01-01

    Within the frame of a contract with the CEC dealing with storage and disposal of radioactive wastes in geological formations, the B.R.G.M. has been involved in a research on process of erosion and denudation. The study is based on a literature survey. It shows that the amplitude of relief is the dominant factor to be considered for ranking erosion rates. Extreme figures of 50 and 500mm per 1,000 years are therefore proposed as mean values of erosion rates, respectively for plains-hills and mountains, for indurated rocks and for non-periglacial climates. Coefficients must correct these values when dealing with softer rocks or periglacial climates. All these factors are liable to change as functions of the surface areas of the morphological units considered

  8. Uncertainties of Gaseous Oxidized Mercury Measurements Using KCl-Coated Denuders, Cation-Exchange Membranes, and Nylon Membranes: Humidity Influences.

    Science.gov (United States)

    Huang, Jiaoyan; Gustin, Mae Sexauer

    2015-05-19

    Quantifying the concentration of gaseous oxidized mercury (GOM) and identifying the chemical compounds in the atmosphere are important for developing accurate local, regional, and global biogeochemical cycles. The major hypothesis driving this work was that relative humidity affects collection of GOM on KCl-coated denuders and nylon membranes, both currently being applied to measure GOM. Using a laboratory manifold system and ambient air, GOM capture efficiency on 3 different collection surfaces, including KCl-coated denuders, nylon membranes, and cation-exchange membranes, was investigated at relative humidity ranging from 25 to 75%. Recovery of permeated HgBr2 on KCl-coated denuders declined by 4-60% during spikes of relative humidity (25 to 75%). When spikes were turned off GOM recoveries returned to 60 ± 19% of permeated levels. In some cases, KCl-coated denuders were gradually passivated over time after additional humidity was applied. In this study, GOM recovery on nylon membranes decreased with high humidity and ozone concentrations. However, additional humidity enhanced GOM recovery on cation-exchange membranes. In addition, reduction and oxidation of elemental mercury during experiments was observed. The findings in this study can help to explain field observations in previous studies.

  9. Denudational slope processes and slope response to global climate changes and other disturbances: insights from the Nepal Himalayas.

    Science.gov (United States)

    Fort, Monique

    2016-04-01

    Hillslope geomorphology results from a large range of denudational processes mainly controlled by relief, structure, lithology, climate, land-cover and land use. In most areas of the world, the "critical zone" concept is a good integrator of denudation that operates on a long-term scale. However, in large and high mountain areas, short-time scale factors often play a significant role in the denudational pattern, accelerating and/or delaying the transfer of denudation products and fluxes, and creating specific, spatially limited disturbances. We focus on the Nepal Himalayas, where the wide altitudinal range of bio-climatic zones and the intense geodynamic activity create a complex mosaic of landforms, as expressed by the present geomorphology of mountain slopes. On the basis of examples selected in the different Himalayan mountain belts (Siwaliks hills, middle mountains, High Himalaya), we illustrate different types of slopes and disturbances induced by active tectonics, climate extremes, and climate warming trends. Special attention is paid to recent events, such as landslide damming, triggered by either intense rainfalls (Kali Gandaki and Sun Kosi valleys) or the last April-May 2015 Gorkha seismic sequence (southern Khumbu). Lastly, references to older, larger events show that despite the highly dynamic environment, landforms caused by large magnitude disturbances may persist in the landscape in the long term.

  10. Wet effluent diffusion denuder technique and determination of volatile organic compounds in air. I. Oxo compounds (alcohols and ketones)

    Czech Academy of Sciences Publication Activity Database

    Sklenská, Jana; Pařízek, Petr; Večeřa, Zbyněk

    2001-01-01

    Roč. 918, č. 1 (2001), s. 153-158 ISSN 0021-9673 R&D Projects: GA ČR GA203/98/0943 Institutional research plan: CEZ:AV0Z4031919 Keywords : diffusion denuders * alcohols * air analysis Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.793, year: 2001

  11. Decreased Neointimal Extracellular Matrix Formation in RAGE-Knockout Mice After Microvascular Denudation

    Energy Technology Data Exchange (ETDEWEB)

    Groezinger, Gerd, E-mail: gerd.groezinger@med.uni-tuebingen.de; Schmehl, Joerg, E-mail: joerg.schmehl@med.uni-tuebingen.de; Bantleon, Ruediger, E-mail: ruediger.bantleon@med.uni-tuebingen.de; Kehlbach, Rainer, E-mail: rainer.kehlbach@uni-tuebingen.de [University of Tuebingen, Department of Diagnostic and Interventional Radiology (Germany); Mehra, Tarun, E-mail: tarun.mehra@med.uni-tuebingen.de [University of Tuebingen, Department of Dermatology (Germany); Claussen, Claus, E-mail: gerd.groezinger@med.uni-tuebingen.de; Wiesinger, Benjamin, E-mail: benjamin.wiesinger@med.uni-tuebingen.de [University of Tuebingen, Department of Diagnostic and Interventional Radiology (Germany)

    2012-12-15

    Purpose: To evaluate in vivo the role of RAGE (receptor for advanced glycated end products) in the development of restenosis and neointimal proliferation in RAGE-deficient knockout (KO) mice compared with wild-type (WT) mice in an animal model. Materials and Methods: Sixteen WT and 15 RAGE-deficient mice underwent microvascular denudation of the common femoral artery under general anaesthesia. Contralateral arteries underwent a sham operation and served as controls. Four weeks after the intervention, all animals were killed, and paraformaldehyde-fixed specimens of the femoral artery were analysed with different stains (hematoxylin and eosin and Elastica van Gieson) and several different types of immunostaining (proliferating cell nuclear antigen, {alpha}-actin, collagen, von Willebrand factor, RAGE). Luminal area, area of the neointima, and area of the media were measured in all specimens. In addition, colony-formation assays were performed, and collagen production by WT smooth muscle cells (SMCs) and RAGE-KO SMCs was determined. For statistical analysis, P < 0.05 was considered statistically significant. Results: Four weeks after denudation, WT mice showed a 49.6% loss of luminal area compared with 14.9% loss of luminal area in RAGE-deficient mice (sham = 0% loss) (P < 0.001). The neointima was 18.2 (*1000 {mu}m{sup 2} [n = 15) in the WT group compared with only 8.4 (*1000 {mu}m{sup 2} [n = 16]) in the RAGE-KO group. RAGE-KO SMCs showed significantly decreased proliferation activity and production of extracellular matrix protein. Conclusion: RAGE may be shown to play a considerable role in the formation of neointima leading to restenosis after vascular injury.

  12. Inhibited osteoclastic bone resorption through alendronate treatment in rats reduces severe osteoarthritis progression.

    Science.gov (United States)

    Siebelt, M; Waarsing, J H; Groen, H C; Müller, C; Koelewijn, S J; de Blois, E; Verhaar, J A N; de Jong, M; Weinans, H

    2014-09-01

    Osteoarthritis (OA) is a non-rheumatoid joint disease characterized by progressive degeneration of extra-cellular cartilage matrix (ECM), enhanced subchondral bone remodeling, osteophyte formation and synovial thickening. Alendronate (ALN) is a potent inhibitor of osteoclastic bone resorption and results in reduced bone remodeling. This study investigated the effects of pre-emptive use of ALN on OA related osteoclastic subchondral bone resorption in an in vivo rat model for severe OA. Using multi-modality imaging we measured effects of ALN treatment within cartilage and synovium. Severe osteoarthritis was induced in left rat knees using papain injections in combination with a moderate running protocol. Twenty rats were treated with subcutaneous ALN injections and compared to twenty untreated controls. Animals were longitudinally monitored for 12weeks with in vivo μCT to measure subchondral bone changes and SPECT/CT to determine synovial macrophage activation using a folate-based radiotracer. Articular cartilage was analyzed at 6 and 12weeks with ex vivo contrast enhanced μCT and histology to measure sulfated-glycosaminoglycan (sGAG) content and cartilage thickness. ALN treatment successfully inhibited subchondral bone remodeling. As a result we found less subchondral plate porosity and reduced osteophytosis. ALN treatment did not reduce subchondral sclerosis. However, after the OA induction phase, ALN treatment protected cartilage ECM from degradation and reduced synovial macrophage activation. Surprisingly, ALN treatment also improved sGAG content of tibia cartilage in healthy joints. Our data was consistent with the hypothesis that osteoclastic bone resorption might play an important role in OA and may be a driving force for progression of the disease. However, our study suggest that this effect might not solely be effects on osteoclastic activity, since ALN treatment also influenced macrophage functioning. Additionally, ALN treatment and physical activity

  13. Bone tumor

    Science.gov (United States)

    Tumor - bone; Bone cancer; Primary bone tumor; Secondary bone tumor; Bone tumor - benign ... The cause of bone tumors is unknown. They often occur in areas of the bone that grow rapidly. Possible causes include: Genetic defects ...

  14. Combined nanoindentation testing and scanning electron microscopy of bone and articular calcified cartilage in an equine fracture predilection site

    OpenAIRE

    M Doube; EC Firth; A Boyde; AJ Bushby

    2010-01-01

    Condylar fracture of the third metacarpal bone (Mc3) is the commonest cause of racetrack fatality in Thoroughbred horses. Linear defects involving hyaline articular cartilage, articular calcified cartilage (ACC) and subchondral bone (SCB) have been associated with the fracture initiation site, which lies in the sagittal grooves of the Mc3 condyle. We discovered areas of thickened and abnormally-mineralised ACC in the sagittal grooves of several normal 18-month-old horses, at the same site tha...

  15. Differential denudation across the Judea Range, Israel, suggests the persistence of a rain-shadow since mid Miocene

    Science.gov (United States)

    Ryb, U.; Matmon, A.; Erel, Y.; Haviv, I.; Benedetti, L. C.

    2013-12-01

    The Judea Range which is composed of a thick sequence of Cretaceous marine carbonate rises up to ~1000 m between the Mediterranean Sea and the Dead Sea basins. The western flank of the range faces predominant winds which deliver humidity from the Mediterranean and thus maintains a sub-humid Mediterranean climate (Mean Annual Precipitation (MAP) of 500-700 mm). Over the eastern, leeward side, rain-shadow orographic effect imposes a climatic gradient from Mediterranean near the water divide to hyper-arid near the Dead Sea rift escarpment (MAPMAP values, indicating that chemical weathering is the dominant process of erosion. Long-term denudation rates of interfluves reflect the climatic gradient between the two flanks of the Judea range; over the western, windward, flank of the Judea range, exposed bedrock denude at an average rate of 21×7 mm kyr-1, while over the leeward flank denudation rates drop dramatically, reaching 1-3 mm kyr-1 near the Dead Sea rift escarpment. As a rough measure to the erosion of the Judea Range since it began uplifting in Senonian time, we compare the present envelope-topography (T) of the range with the top-Turonian structural datum (S). We found that over the windward flank topography lay ~300 meters below the datum, while over the leeward flank topography generally follows the datum. Can this difference result from differential denudation, similar to the one observed over 10-1-105 year timescales? S-T values are well correlated with present MAP values, suggesting a positive answer. Assuming that the late Pleistocene denudation pattern calculated from 36Cl data was maintained, ~15 million years are required to form the observed 300 difference between the eastern and western flanks of the range. Indeed, previous studies suggest that by mid Miocene the Judea Range was uplifted to about ~500 m above sea level, while the Mediterranean was the immediate source for humidity in the region as of the early Miocene. The integrated data could

  16. Phanerozoic burial, uplift and denudation of the Equatorial Atlantic margin of South America

    Science.gov (United States)

    Japsen, Peter; Bonow, Johan M.; Green, Paul F.; dall'Asta, Massimo; Roig, Jean-Yves; Theveniaut, Hervé

    2017-04-01

    We have initiated a study aimed at understanding the history of burial, uplift and denudation of the South American Equatorial Atlantic Margin (SAEAM Uplift) including the Guiana Shield to provide a framework for investigating the hydrocarbon prospectivity of the offshore region. We report first results including observations from fieldwork at the northern and southern flank of the Guiana Shield. The study combines apatite fission-track analysis (AFTA) and vitrinite reflectance data from samples of outcrops and drillcores, sonic velocity data from drill holes and stratigraphic landscape analysis (mapping of peneplains) - all constrained by geological evidence, following the methods of Green et al. (2013). The study will thus combine the thermal history from AFTA data with the denudation history from stratigraphic landscape analysis to provide magnitudes and timing of vertical movements (Japsen et al. 2012, 2016). Along the Atlantic margin of Suriname and French Guiana, tilted and truncated Lower Cretaceous strata rest on Precambrian basement (Sapin et al. 2016). Our AFTA data show that the basement underwent Mesozoic exhumation prior to deposition of the Lower Cretaceous cover. Sub-horizontal peneplains define the landscape of the Guiana Shield at elevations up to 500 m a.s.l. As these sub-horizontal peneplains truncate the tilted, sub-Cretaceous surface along the Atlantic margin, these peneplains were therefore formed and uplifted in post-Cretaceous time. This interpretation is in good agreement with our AFTA data that define Paleogene exhumation along the margin and with the results of Theveniaut and Freyssinet (2002) who used palaeomagnetic data to conclude that bauxitic surfaces across basement at up to 400 m a.s.l. on the Guiana Shield formed during the Palaeogene. Integration of the results from AFTA with stratigraphic landscape analysis (currently in progress) and geological evidence will provide a robust reconstruction of the tectonic development of the

  17. Bone strength and material properties of the glenoid

    DEFF Research Database (Denmark)

    Frich, Lars Henrik; Jensen, N.C.; Odgaard, A.

    1997-01-01

    of bone specimens harvested from the central part of the glenoid subchondral area. The elastic modulus varied from approximately 100 MPa at the glenoid bare area to 400 MPa at the superior part of the glenoid. With the elastic constants used a predictor of the mechanical anisotropy, the average anisotropy...... ratio was 5.2, indicating strong anisotropy. The apparent density was an average 0.35 gr. cm-3, and the Poisson ratio averaged 0.263. According to our findings the anisotropy of the glenoid cancellous bone, details concerning the strength distribution, and the load-bearing function of the cortical shell......The quality of the glenoid bone is important to a successful total shoulder replacement. Finite element models have been used to model the response of the glenoid bone to an implanted prosthesis. Because very little is known about the bone strength and the material properties at the glenoid...

  18. Computerized bone density analysis of the proximal phalanx of the horse

    International Nuclear Information System (INIS)

    Thompson, K.N.; Cheung, T.K.; Putnam, M.

    1996-01-01

    This study utilized computed tomography to determine the density patterns and the subchondral bone thickness of the first phalanx of the horse. An image processing system and commercially available software were used to process the computed tomographic slices obtained from the first phalanges of a 2-year-old Thoroughbred horse. The thickness and density of the medial and lateral cortices in the mid-shaft of the bone were similar; however, the cortex on the dorsal aspect was more dense and extended farther toward the proximal and distal aspects of the bone than the cortex on the palmar aspect. Density of the cortical bone was highest at the region of the bone with the smallest diameter. The cortical bone density at mid-shaft was approximately 3.5 times the cancellous bone density at the proximal aspect and 2.5 times that at the distal aspect of the bone. A moderate correlation (r = 0.53, p < 0.01)was found between the subchondral bone density and thickness. Despite limited numbers of specimens used, this study demonstrated the potential applications of computed tomography for investigating equine joint mechanics and diseases

  19. Some geomorphological features of the Orhaneli Pluton: Implications for denudation history

    Directory of Open Access Journals (Sweden)

    Ahmet Evren ERGİNAL

    2008-12-01

    Full Text Available The granitic intrusions of the variable age of cooling, size and mineral composition are widely exposed in the northwest Anatolia, Turkey. The nearly circular Orhaneli Pluton emplaced during the Early Eocene with some 15 km in diameter, is one of such plutonic bodies. Geomorphological features of the pluton are discussed here with special emphasis given on the denudation history. To this end, evidence from two isolated Inselberglike hills as remnants of roof rocks in the centre of the pluton and episodically emergence of granite landforms of etch origin after unroofing process were investigated. Field data reveal the absence of granodiorite clasts within Early to Middle Miocene lacustrine deposits in the north of the pluton, implying that the pluton might not have been exposure prior to Upper Miocene as a whole. After the first exposure, the granite landforms, such as boulders, corestones and tors constituting sound evidence of an etch origin, became exposure by continual removing of regolith cover by surficial runoff. These forms of various scale were formed at first by subsurface weathering and shaped by surficial weathering processes after any stages of removal of the regolith cover. Drainage segments accounted for removal of regolith is mostly structurally controlled defined by NW-SE, NE-SW and N-S-aligned fracture systems.

  20. Radiographic analysis of pasteurized autologous bone graft

    International Nuclear Information System (INIS)

    Ahmed, Adel Refaat; Manabe, Jun; Kawaguchi, Noriyoshi; Matsumoto, Seiichi; Matsushita, Yasushi

    2003-01-01

    Local malignant bone tumor excision followed by pasteurization and subsequent reimplantation is a unique technique for reconstruction after resection of primary bone sarcomas. The purpose of this investigation was to assess the normal and abnormal long-term radiographic findings of intercalary and osteo-chondral pasteurized bone graft/implant composite. The long-term radiographic findings of pasteurized bone grafts used in reconstruction after resection of bone and soft tissue sarcomas in relation to patients' clinical data were reviewed retrospectively. Thirty-one patients (18 females, 13 males; age range 7-77 years, mean 30 years) who underwent surgery between April 1990 and January 1997 at the authors' institute constituted the material of this study. They were followed up for at least 3 years or until the patient's death (mean 69 months). The International Society of Limb Salvage graft evaluation method that assesses the fusion, resorption, fracture, graft shortening, fixation, subluxation, joint narrowing and subchondral bone was used for evaluation of the radiographs. Twenty-one patients (68%) showed complete incorporation of graft and eight patients (26%) had partial incorporation. The overall radiographic evaluation rate was 81%. Fracture (10%) and infection (16%) were the main complications. No local recurrence was detected. These results indicate that pasteurization of bone is a useful option for reconstruction after resection of malignant bone tumors. (orig.)

  1. Radiographic analysis of pasteurized autologous bone graft

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Adel Refaat [Department of Orthopedic Surgery, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Kamiikebukuro 1-37-1, Toshima-ku, 170-0012, Tokyo (Japan); Department of Orthopedic Surgery, Alexandria University, Alexandria (Egypt); Manabe, Jun; Kawaguchi, Noriyoshi; Matsumoto, Seiichi; Matsushita, Yasushi [Department of Orthopedic Surgery, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Kamiikebukuro 1-37-1, Toshima-ku, 170-0012, Tokyo (Japan)

    2003-08-01

    Local malignant bone tumor excision followed by pasteurization and subsequent reimplantation is a unique technique for reconstruction after resection of primary bone sarcomas. The purpose of this investigation was to assess the normal and abnormal long-term radiographic findings of intercalary and osteo-chondral pasteurized bone graft/implant composite. The long-term radiographic findings of pasteurized bone grafts used in reconstruction after resection of bone and soft tissue sarcomas in relation to patients' clinical data were reviewed retrospectively. Thirty-one patients (18 females, 13 males; age range 7-77 years, mean 30 years) who underwent surgery between April 1990 and January 1997 at the authors' institute constituted the material of this study. They were followed up for at least 3 years or until the patient's death (mean 69 months). The International Society of Limb Salvage graft evaluation method that assesses the fusion, resorption, fracture, graft shortening, fixation, subluxation, joint narrowing and subchondral bone was used for evaluation of the radiographs. Twenty-one patients (68%) showed complete incorporation of graft and eight patients (26%) had partial incorporation. The overall radiographic evaluation rate was 81%. Fracture (10%) and infection (16%) were the main complications. No local recurrence was detected. These results indicate that pasteurization of bone is a useful option for reconstruction after resection of malignant bone tumors. (orig.)

  2. Platelet-Rich Plasma Preparation Types Show Impact on Chondrogenic Differentiation, Migration, and Proliferation of Human Subchondral Mesenchymal Progenitor Cells.

    Science.gov (United States)

    Kreuz, Peter Cornelius; Krüger, Jan Philipp; Metzlaff, Sebastian; Freymann, Undine; Endres, Michaela; Pruss, Axel; Petersen, Wolf; Kaps, Christian

    2015-10-01

    To evaluate the chondrogenic potential of platelet concentrates on human subchondral mesenchymal progenitor cells (MPCs) as assessed by histomorphometric analysis of proteoglycans and type II collagen. Furthermore, the migratory and proliferative effect of platelet concentrates were assessed. Platelet-rich plasma (PRP) was prepared using preparation kits (Autologous Conditioned Plasma [ACP] Kit [Arthrex, Naples, FL]; Regen ACR-C Kit [Regen Lab, Le Mont-Sur-Lausanne, Switzerland]; and Dr.PRP Kit [Rmedica, Seoul, Republic of Korea]) by apheresis (PRP-A) and by centrifugation (PRP-C). In contrast to clinical application, freeze-and-thaw cycles were subsequently performed to activate platelets and to prevent medium coagulation by residual fibrinogen in vitro. MPCs were harvested from the cortico-spongious bone of femoral heads. Chondrogenic differentiation of MPCs was induced in high-density pellet cultures and evaluated by histochemical staining of typical cartilage matrix components. Migration of MPCs was assessed using a chemotaxis assay, and proliferation activity was measured by DNA content. MPCs cultured in the presence of 5% ACP, Regen, or Dr.PRP formed fibrous tissue, whereas MPCs stimulated with 5% PRP-A or PRP-C developed compact and dense cartilaginous tissue rich in type II collagen and proteoglycans. All platelet concentrates significantly (ACP, P = .00041; Regen, P = .00029; Dr.PRP, P = .00051; PRP-A, P platelet concentrates but one (Dr.PRP, P = .63) showed a proliferative effect on MPCs, as shown by significant increases (ACP, P = .027; Regen, P = .0029; PRP-A, P = .00021; and PRP-C, P = .00069) in DNA content. Platelet concentrates obtained by different preparation methods exhibit different potentials to stimulate chondrogenic differentiation, migration, and proliferation of MPCs. Platelet concentrates obtained by commercially available preparation kits failed to induce chondrogenic differentiation of MPCs, whereas highly standardized PRP

  3. Effect of antiresorptive and anabolic bone therapy on development of osteoarthritis in a posttraumatic rat model of OA.

    Science.gov (United States)

    Bagi, Cedo M; Berryman, Edwin; Zakur, David E; Wilkie, Dean; Andresen, Catharine J

    2015-11-06

    Osteoarthritis (OA) is a leading cause of disability, but despite the high unmet clinical need and extensive research seeking dependable therapeutic interventions, no proven disease-modifying treatment for OA is currently available. Due to the close interaction and interplay between the articular cartilage and the subchondral bone plate, it has been hypothesized that antiresorptive drugs can also reduce cartilage degradation, inhibit excessive turnover of the subchondral bone plate, prevent osteophyte formation, and/or that bone anabolic drugs might also stimulate cartilage synthesis by chondrocytes and preserve cartilage integrity. The benefit of intensive zoledronate (Zol) and parathyroid hormone (PTH) therapy for bone and cartilage metabolism was evaluated in a rat model of OA. Medial meniscectomy (MM) was used to induce OA in male Lewis rats. Therapy with Zol and human PTH was initiated immediately after surgery. A dynamic weight-bearing (DWB) system was deployed to evaluate the weight-bearing capacity of the front and hind legs. At the end of the 10-week study, the rats were euthanized and the cartilage pathology was evaluated by contrast (Hexabrix)-enhanced μCT imaging and traditional histology. Bone tissue was evaluated at the tibial metaphysis and epiphysis, including the subchondral bone. Histological techniques and dynamic histomorphometry were used to evaluate cartilage morphology and bone mineralization. The results of this study highlight the complex changes in bone metabolism in different bone compartments influenced by local factors, including inflammation, pain and mechanical loads. Surgery caused severe and extensive deterioration of the articular cartilage at the medial tibial plateau, as evidenced by contrast-enhanced μCT and histology. The study results showed the negative impact of MM surgery on the weight-bearing capacity of the operated limb, which was not corrected by treatment. Although both Zol and PTH improved subchondral bone mass and

  4. Luminescence of quartz and feldspar fingerprints provenance and correlates with the source area denudation in the Amazon River basin

    Science.gov (United States)

    Sawakuchi, A. O.; Jain, M.; Mineli, T. D.; Nogueira, L.; Bertassoli, D. J.; Häggi, C.; Sawakuchi, H. O.; Pupim, F. N.; Grohmann, C. H.; Chiessi, C. M.; Zabel, M.; Mulitza, S.; Mazoca, C. E. M.; Cunha, D. F.

    2018-06-01

    The Amazon region hosts the world's largest watershed spanning from high elevation Andean terrains to lowland cratonic shield areas in tropical South America. This study explores variations in optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL) signals in suspended silt and riverbed sands retrieved from major Amazon rivers. These rivers drain Pre-Cambrian to Cenozoic source rocks in areas with contrasting denudation rates. In contrast to the previous studies, we do not observe an increase in the OSL sensitivity of quartz with transport distance; for example, Tapajós and Xingu Rivers show more sensitive quartz than Solimões and Madeira Rivers, even though the latter have a significantly larger catchment area and longer sediment transport distance. Interestingly, high sensitivity quartz is observed in rivers draining relatively stable Central Brazil and Guiana shield areas (denudation rate ξ = 0.04 mmyr-1), while low sensitivity quartz occurs in less stable Andean terrains (ξ = 0.24 mmyr-1). An apparent linear correlation between quartz OSL sensitivity and denudation rate suggests that OSL sensitivity may be used as a proxy for erosion rates in the Amazon basin. Furthermore, luminescence sensitivity measured in sand or silt arises from the same mineral components (quartz and feldspar) and clearly discriminates between Andean and shield sediments, avoiding the grain size bias in provenance analysis. These results have implications for using luminescence sensitivity as a proxy for Andean and shield contributions in the stratigraphic record, providing a new tool to reconstruct past drainage configurations within the Amazon basin.

  5. Impact of double-tiered subchondral support procedure with a polyaxial locking plate on the stability of distal radius fractures using fresh cadaveric forearms: Biomechanical and radiographic analyses.

    Science.gov (United States)

    Tsutsui, Sadaaki; Kawasaki, Keikichi; Yamakoshi, Ken-Ichi; Uchiyama, Eiichi; Aoki, Mitsuhiro; Inagaki, Katsunori

    2016-09-01

    The present study compared the changes in biomechanical and radiographic properties under cyclic axial loadings between the 'double-tiered subchondral support' (DSS) group (wherein two rows of screws were used) and the 'non-DSS' (NDSS) group (wherein only one row of distal screws was used) using cadaveric forearm models of radius fractures fixed with a polyaxial locking plate. Fifteen fresh cadaveric forearms were surgically operated to generate an Arbeitsgemeinschaft für Osteosynthesefragen (AO) type 23-C2 fracture model with the fixation of polyaxial volar locking plates. The model specimens were randomized into two groups: DSS (n = 7) and NDSS (n = 8). Both the groups received 4 locking screws in the most distal row, as is usually applied, whereas the DSS group received 2 additional screws in the second row inserted at an inclination of about 15° to support the dorsal aspect of the dorsal subchondral bone. Cyclic axial compression test was performed (3000 cycles; 0-250 N; 60 mm/min) to measure absolute rigidity and displacement, after 1, 1000, 2000 and 3000 cycles, and values were normalized relative to cycle 1. These absolute and normalized values were compared between those two groups. Radiographic images were taken before and after the cyclic loading to measure changes in volar tilt (ΔVT) and radial inclination (ΔRI). The DSS group maintained significantly higher rigidity and lower displacement values than the NDSS group during the entire loading period. Radiographic analysis indicated that the ΔVT values of the DSS group were lower than those of the NDSS group. In contrast, the fixation design did not influence the impact of loading on the ΔRI values. Biomechanical and radiographic analyses demonstrated that two rows of distal locking screws in the DSS procedure conferred higher stability than one row of distal locking screws. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  6. Constraints on early Cenozoic underplating-driven uplift and denudation of western Scotland from low temperature thermochronometry

    Science.gov (United States)

    Persano, Cristina; Barfod, Dan N.; Stuart, Finlay M.; Bishop, Paul

    2007-11-01

    Apatite (U-Th)/He and fission track data from profiles in western Scotland constrain the timing and magnitude of denudation during the early Cenozoic when the north Atlantic region was the site of intense magmatic activity related to the proto-Icelandic plume. Apatite helium ages vary from 77 ± 8 to 265 ± 27 Ma (± 2 σ) at Sgorr Dhonuill, Ballachulish, and from 104 ± 10 Ma to 166 ± 17 Ma at Clisham, Outer Hebrides. At both locations apatite fission track (AFT) ages are older than the corresponding He ages; at Clisham they vary from 189 ± 28 Ma to 242 ± 26 Ma, and from 186 ± 6 Ma to 257 ± 12 Ma at Sgorr Dhonuill. Apatite He ages increase linearly with elevation suggesting that the cooling rate remained constant in the late Mesozoic. However, the apatite He age profile requires a period of rapid cooling after ˜ 100 Ma. Apatite He ages predicted from the AFT-derived thermal histories are indistinguishable from measured He ages for a rapid cooling event of 1 to 10 Myr duration between 61 and 47 Ma at Sgorr Dhonuill and 65 to 49 Ma at Clisham. The combined apatite FT- and He-derived thermal histories constrain the early Cenozoic geothermal gradient at 39 ± 9 °C/km at Sgorr Dhonuill and 19 ± 6 °C/km at Clisham. Amounts of denudation related to the rapid cooling event vary from 1330 ± 230 m at Sgorr Dhonuill to 2250 ± 750 m at Clisham, in agreement with models that predict greater amounts of denudation where magmatic underplating is thicker. However, the direct correlation between underplating-driven surface uplift and denudation may only be apparent and a more complex link between spatial variation of surface uplift and denudation is suggested. The integration of results from multiple low-temperature thermochronometers, combined with inverse and forward modelling, provides a convincing and quantitative method to deduce onshore erosional histories, and provides critical information about the spatial distribution of erosion that cannot be derived from the

  7. Subchondral Impaction Fractures of the Medial Femoral Condyle in Weightlifters: A Report of 5 Cases.

    Science.gov (United States)

    Grzelak, Piotr; Podgórski, Michał Tomasz; Stefańczyk, Ludomir; Krochmalski, Marek; Domżalski, Marcin

    2016-01-01

    Although subchondral impaction fractures have already been reported in the non-weight-bearing portion of the lateral femoral condyle, this study reveals the presence of an intra-articular impaction fracture of the postero-superior region of the non-weight-bearing portion of the medial femoral condyle recognized in 5 of a group of 22 representatives of the Polish national Olympic weightlifting team, who underwent 1.5T magnetic resonance imaging examination. Articular cartilage lesions varied with regard to the type of injury and its severity ranging from healed or subchronic injuries to acute trauma. All described individuals had no clinical history of acute knee trauma and only 3 of them had minor pain symptoms. The accumulation of microtraumas occurring during participation in particular activities associated with weightlifting training seems to be responsible for the development of this type of contusion. This is the first description of impaction fracture observed in this location in professional weightlifters.

  8. Cartilage degeneration in the human patellae and its relationship to the mineralisation of the underlying bone: a key to the understanding of chondromalacia patellae and femoropatellar arthrosis?

    Science.gov (United States)

    Eckstein, F; Putz, R; Müller-Gerbl, M; Steinlechner, M; Benedetto, K P

    1993-01-01

    According to the literature subchondral bone plays a significant role in the transmission of load through joints and in the pathogenesis of osteoarthrosis. Therefore the degeneration of the articular cartilage was investigated in the patellae from 30 dissecting-room specimens and of 20 patients, previously submitted to arthroscopy, and subchondral mineralisation of their underlying bone was at the same time assessed by means of CT osteoabsorptiometry. Lateral cartilage lesions were localised over highly mineralised subchondral bone; these appear to be due to long-term stress. They were mainly found in the older specimens and showed a high rate of progression with increasing age. Medially localised cartilage lesions, on the other hand, were situated in a transitional region between moderate and slight subchondral mineralisation; they may be caused by infrequent stress peaks and by shear stress in the articular cartilage, the very medial part of the joint being deprived of mechanical stimulation for much of the time. These lesions were to be found predominantly in the younger specimens and showed little progress with advancing age. Patients with lateral cartilage degeneration exhibited higher, patients with medial chondromalacia patellae lower mineralisation than normals. Their density patterns therefore indicate a different mechanical pathogenesis of the cartilage lesions in the lateral and medial facet. It could be shown that CT osteoabsorptiometry allows an assessment of the mechanical situation, present in individual femoro-patellar joints, and that this situation is highly relevant for the pathogenesis of patellar cartilage degeneration.

  9. Landscape evolution on Mars - A model of aeolian denudation in Gale Crater

    Science.gov (United States)

    Day, M. D.; Kocurek, G.; Grotzinger, J. P.

    2015-12-01

    Aeolian erosion has been the dominant geomorphic agent to shape the surface of Mars for the past ~3.5 billion years. Although individual geomorphic features evidencing aeolian activity are well understood (e.g., yardangs, dune fields, and wind streaks), landscapes formed by aeolian erosion remain poorly characterized. Intra-crater sedimentary mounds are hypothesized to have formed by wind deflation of craters once filled with flat-lying strata, and, therefore, should be surrounded by landscapes formed by aeolian erosion. Here we present a landscape evolution model that provides both an initial characterization of aeolian landscapes, and a mechanism for large-scale excavation. Wind excavation of Gale Crater to form the 5 km high Mount Sharp would require removal of 6.4 x 104 km3 of sediment. Imagery in Gale Crater from satellites and the Mars Science Laboratory rover Curiosity shows a surface characterized by first-cycle aeolian erosion of bedrock. The overall landscape is interpreted to represent stages in a cycle of aeolian deflation and excavation, enhanced by physical weathering (e.g., thermal fracturing, cratering). Initial wind erosion of bedrock is enhanced along fractures, producing retreating scarps. Underlying less resistant layers then erode faster than the armoring cap rock, increasing relief in scarps to form retreating mesas. As scarp retreat continues, boulders from the armoring cap unit break away and cover the hillslopes of less resistant material below the scarps. Eventually all material from the capping unit is eroded away and a boulder-capped hill remains. Winnowing of fine material flattens hillslope topography, leaving behind a desert pavement. Over long enough time, this pavement is breached and the cycle begins anew. This cycle of landscape denudation by the wind is similar to that of water, but lacks characteristic subaqueous features such as dendritic drainage networks.

  10. Cenozoic landforms and post-orogenic landscape evolution of the Balkanide orogen: Evidence for alternatives to the tectonic denudation narrative in southern Bulgaria

    Science.gov (United States)

    Gunnell, Y.; Calvet, M.; Meyer, B.; Pinna-Jamme, R.; Bour, I.; Gautheron, C.; Carter, A.; Dimitrov, D.

    2017-01-01

    Continental denudation is the mass transfer of rock from source areas to sedimentary depocentres, and is typically the result of Earth surface processes. However, a process known as tectonic denudation is also understood to expose deep-seated rocks in short periods of geological time by displacing large masses of continental crust along shallow-angle faults, and without requiring major contributions from surface erosion. Some parts of the world, such as the Basin and Range in the USA or the Aegean province in Europe, have been showcased for their Cenozoic tectonic denudation features, commonly described as metamorphic core-complexes or as supradetachment faults. Based on 22 new apatite fission-track (AFT) and 21 helium (AHe) cooling ages among rock samples collected widely from plateau summits and their adjacent valley floors, and elaborating on inconsistencies between the regional stratigraphic, topographic and denudational records, this study frames a revised perspective on the prevailing tectonic denudation narrative for southern Bulgaria. We conclude that conspicuous landforms in this region, such as erosion surfaces on basement-cored mountain ranges, are not primarily the result of Paleogene to Neogene core-complex formation. They result instead from "ordinary" erosion-driven, subaerial denudation. Rock cooling, each time suggesting at least 2 km of crustal denudation, has exposed shallow Paleogene granitic plutons and documents a 3-stage wave of erosional denudation which progressed from north to south during the Middle Eocene, Oligocene, Early to Middle Miocene, and Late Miocene. Denudation initially prevailed during the Paleogene under a syn-orogenic compressional regime involving piggyback extensional basins (Phase 1), but subsequently migrated southward in response to post-orogenic upper-plate extension driven by trench rollback of the Hellenic subduction slab (Phase 2). Rare insight given by the denudation pattern indicates that trench rollback

  11. A Dual Role of Upper Zone of Growth Plate and Cartilage Matrix-Associated Protein in Human and Mouse Osteoarthritic Cartilage: Inhibition of Aggrecanases and Promotion of Bone Turnover

    NARCIS (Netherlands)

    Stock, M.; Menges, S.; Eitzinger, N.; Gesslein, M.; Botschner, R.; Wormser, L.; Distler, A.; Schlotzer-Schrehardt, U.; Dietel, K.; Distler, J.; Beyer, C.; Gelse, K.; Engelke, K.; Koenders, M.I.; Berg, W.B. van den; Mark, K. von der; Schett, G.

    2017-01-01

    OBJECTIVE: Cartilage damage and subchondral bone changes are closely connected in osteoarthritis. Nevertheless, how these processes are interlinked is, to date, incompletely understood. This study was undertaken to investigate the mechanistic role of a cartilage-derived protein, upper zone of growth

  12. Roles of Chondrocytes in Endochondral Bone Formation and Fracture Repair

    Science.gov (United States)

    Hinton, R.J.; Jing, Y.; Jing, J.; Feng, J.Q.

    2016-01-01

    The formation of the mandibular condylar cartilage (MCC) and its subchondral bone is an important but understudied topic in dental research. The current concept regarding endochondral bone formation postulates that most hypertrophic chondrocytes undergo programmed cell death prior to bone formation. Under this paradigm, the MCC and its underlying bone are thought to result from 2 closely linked but separate processes: chondrogenesis and osteogenesis. However, recent investigations using cell lineage tracing techniques have demonstrated that many, perhaps the majority, of bone cells are derived via direct transformation from chondrocytes. In this review, the authors will briefly discuss the history of this idea and describe recent studies that clearly demonstrate that the direct transformation of chondrocytes into bone cells is common in both long bone and mandibular condyle development and during bone fracture repair. The authors will also provide new evidence of a distinct difference in ossification orientation in the condylar ramus (1 ossification center) versus long bone ossification formation (2 ossification centers). Based on our recent findings and those of other laboratories, we propose a new model that contrasts the mode of bone formation in much of the mandibular ramus (chondrocyte-derived) with intramembranous bone formation of the mandibular body (non-chondrocyte-derived). PMID:27664203

  13. Three-dimensional Microarchitecture of Adolescent Cancellous Bone

    DEFF Research Database (Denmark)

    Ding, Ming; Hvid, I; Overgaard, Søren

    regarding three-dimensional (3-D) microarchitecture of normal adolescent cancellous bone. The objective of this study was to investigate 3-D microarchitecture of normal adolescent cancellous bone, and compared them with adult cancellous bone, thus seeking more insight into the subchondral bone adaptations...... of lateral condyle in the young adult. There were no statistical significances in the mechanical properties apart from the Young’s modulus of adolescent in anterior-posterior direction was significantly lower than the other groups. DISCUSSION: This is the first study on the 3-D microarchitecture of human......, Switzerland) resulting in cubic voxel sizes of 10*10*10 m3. Microarchitectural properties were calculated, and the mean values for either tibia, medial or lateral condyle were used in analyses. Furthermore, the samples were first tested non-destructively in compression in antero-posterior (AP) and medial...

  14. Bone tumors

    International Nuclear Information System (INIS)

    Unni, K.K.

    1988-01-01

    This book contains the proceedings on bone tumors. Topics covered include: Bone tumor imaging: Contribution of CT and MRI, staging of bone tumors, perind cell tumors of bone, and metastatic bone disease

  15. Chemical weathering in response to tectonic uplift and denudation rate in a semi-arid environment, southeast Spain

    Science.gov (United States)

    Ameijeiras-Mariño, Yolanda; Opfergelt, Sophie; Schoonejans, Jérôme; Vanacker, Veerle; Sonnet, Philippe; Delmelle, Pierre

    2014-05-01

    Soil thickness reflects the balance between soil production and denudation by chemical weathering and physical erosion. At topographic steady state, the soil weathering intensity is expected to be higher at low denudation rate (transport-limited) than at high denudation rate (weathering-limited). We tested this hypothesis for the first time in a semi-arid environment where chemical weathering processes are generally slow. The study site is the Internal Zone of the Betic Cordillera in Southeast Spain, Almeria province. The lithology is mainly mica-schist and quartzite with local presence of phyllite. Three catchments (EST, FIL, CAB) were selected upstream local faults along a gradient of increasing uplift rates (10-170 mm/kyr) and increasing denudation rates (20-250 mm/kyr), following the sequence EST

  16. Denudation of the continental shelf between Britain and France at the glacial–interglacial timescale

    Science.gov (United States)

    Mellett, Claire L.; Hodgson, David M.; Plater, Andrew J.; Mauz, Barbara; Selby, Ian; Lang, Andreas

    2013-01-01

    The erosional morphology preserved at the sea bed in the eastern English Channel dominantly records denudation of the continental shelf by fluvial processes over multiple glacial–interglacial sea-level cycles rather than by catastrophic flooding through the Straits of Dover during the mid-Quaternary. Here, through the integration of multibeam bathymetry and shallow sub-bottom 2D seismic reflection profiles calibrated with vibrocore records, the first stratigraphic model of erosion and deposition on the eastern English Channel continental shelf is presented. Published Optical Stimulated Luminescence (OSL) and 14C ages were used to chronometrically constrain the stratigraphy and allow correlation of the continental shelf record with major climatic/sea-level periods. Five major erosion surfaces overlain by discrete sediment packages have been identified. The continental shelf in the eastern English Channel preserves a record of processes operating from Marine Isotope Stage (MIS) 6 to MIS 1. Planar and channelised erosion surfaces were formed by fluvial incision during lowstands or relative sea-level fall. The depth and lateral extent of incision was partly conditioned by underlying geology (rock type and tectonic structure), climatic conditions and changes in water and sediment discharge coupled to ice sheet dynamics and the drainage configuration of major rivers in Northwest Europe. Evidence for major erosion during or prior to MIS 6 is preserved. Fluvial sediments of MIS 2 age were identified within the Northern Palaeovalley, providing insights into the scale of erosion by normal fluvial regimes. Seismic and sedimentary facies indicate that deposition predominantly occurred during transgression when accommodation was created in palaeovalleys to allow discrete sediment bodies to form. Sediment reworking over multiple sea-level cycles (Saalian–Eemian–early Weichselian) by fluvial, coastal and marine processes created a multi-lateral, multi-storey succession of

  17. Denudation of the continental shelf between Britain and France at the glacial-interglacial timescale.

    Science.gov (United States)

    Mellett, Claire L; Hodgson, David M; Plater, Andrew J; Mauz, Barbara; Selby, Ian; Lang, Andreas

    2013-12-01

    The erosional morphology preserved at the sea bed in the eastern English Channel dominantly records denudation of the continental shelf by fluvial processes over multiple glacial-interglacial sea-level cycles rather than by catastrophic flooding through the Straits of Dover during the mid-Quaternary. Here, through the integration of multibeam bathymetry and shallow sub-bottom 2D seismic reflection profiles calibrated with vibrocore records, the first stratigraphic model of erosion and deposition on the eastern English Channel continental shelf is presented. Published Optical Stimulated Luminescence (OSL) and 14 C ages were used to chronometrically constrain the stratigraphy and allow correlation of the continental shelf record with major climatic/sea-level periods. Five major erosion surfaces overlain by discrete sediment packages have been identified. The continental shelf in the eastern English Channel preserves a record of processes operating from Marine Isotope Stage (MIS) 6 to MIS 1. Planar and channelised erosion surfaces were formed by fluvial incision during lowstands or relative sea-level fall. The depth and lateral extent of incision was partly conditioned by underlying geology (rock type and tectonic structure), climatic conditions and changes in water and sediment discharge coupled to ice sheet dynamics and the drainage configuration of major rivers in Northwest Europe. Evidence for major erosion during or prior to MIS 6 is preserved. Fluvial sediments of MIS 2 age were identified within the Northern Palaeovalley, providing insights into the scale of erosion by normal fluvial regimes. Seismic and sedimentary facies indicate that deposition predominantly occurred during transgression when accommodation was created in palaeovalleys to allow discrete sediment bodies to form. Sediment reworking over multiple sea-level cycles (Saalian-Eemian-early Weichselian) by fluvial, coastal and marine processes created a multi-lateral, multi-storey succession of

  18. Incipient boninitic arc crust built on denudated mantle: the Khantaishir ophiolite (western Mongolia)

    Science.gov (United States)

    Gianola, Omar; Schmidt, Max W.; Jagoutz, Oliver; Sambuu, Oyungerel

    2017-12-01

    The 570 Ma old Khantaishir ophiolite is built by up to 4 km harzburgitic mantle with abundant pyroxenites and dunites followed by 2 km of hornblende-gabbros and gabbronorites and by a 2.5 km thick volcanic unit composed of a dyke + sill complex capped by pillow lavas and some volcanoclastics. The volcanics are mainly basaltic andesites and andesites (or boninites) with an average of 58.2 ± 1.0 wt% SiO2, X Mg = 0.61 ± 0.03 ( X Mg = molar MgO/(MgO + FeOtot), TiO2 = 0.4 ± 0.1 wt% and CaO = 7.5 ± 0.6 wt% (errors as 2 σ). Normalized trace element patterns show positive anomalies for Pb and Sr, a negative Nb-anomaly, large ion lithophile elements (LILE) concentrations between N- and E-MORB and distinctly depleted HREE. These characteristics indicate that the Khantaishir volcanics were derived from a refractory mantle source modified by a moderate slab-component, similar to boninites erupted along the Izu-Bonin-Mariana subduction system and to the Troodos and Betts Cove ophiolites. Most strikingly and despite almost complete outcrops over 260 km2, there is no remnant of any pre-existing MORB crust, suggesting that the magmatic suite of this ophiolite formed on completely denudated mantle, most likely upon subduction initiation. The architecture of this 4-5 km thick early arc crust resembles oceanic crust formed at mid ocean ridges, but lacks a sheeted dyke complex; volcanic edifices are not observed. Nevertheless, low melting pressures combined with moderate H2O-contents resulted in high-Si primitive melts, in abundant hornblende-gabbros and in a fast enrichment in bulk SiO2. Fractional crystallization modeling starting from the observed primitive melts (56.6 wt% SiO2) suggests that 25 wt% pyroxene + plagioclase fractionation is sufficient to form the average Khantaishir volcanic crust. Most of the fractionation happened in the mantle, the observed pyroxenite lenses and layers in and at the top of the harzburgites account for the required cumulate volumes. Finally

  19. Microvascular denudation of the femoral artery of the mouse as a model for restenosis

    International Nuclear Information System (INIS)

    Feuls, R.; Bantleon, R.; Henning, E.B.; Tepe, G.; Khorchidi, S.; Reis, E.D.; Duda, S.H.; Chereshnev, I.

    2003-01-01

    Objective: To present technique and results of a microvascular denudation of the common femoral artery of the mouse as a model for inducing intimal hyperplasia in interventional radiology. Materials and methods: Under general anesthesia introduced by intraperitoneal injection, 14 B6129F1 hybrid mice (7 females and 7 males) at a mean age of 12.1±1.8 weeks and a mean weight of 28±2.8 grams had a groin incision of the vascular bundle directly distal to the inguinal ligament in preparation of placing a vascular clamp. Thereafter, the femoral artery was dissected distal to the origin of the epigastric artery and a loop prepared for a ligation proximal to the planned arteriotomy. Through an arteriotomy performed free-hand with a pair of micro scissors, a 0.010'' (=0.25 mm) guidewire was introduced into the vessel and advanced to the aortic bifurcation. The guidewire was moved back and forth three times. The same procedure was performed on the other side as sham-operation, i.e., without introduction and passage of a guidewire. The resulting changes of the vessel wall were evaluated by histology and morphometry. Results: Four weeks after intervention, the mean intima-to-media-ratio (IMR) was 1.80±0.28. A significant difference was observed between the sexes, with an IMR of 1.41±0.29 in females and an IMR of 2.24±0.45 in males (p=0.0173). The neointima led to an overall luminal loss of 50.2%±8.3% without significant sex difference (p=0.09), but the average lumina loss was still more severe in females, amounting to 43.9% in comparison to 56.1% in males. This technique induces a significant neointima formation in a reproducible manner. The internal elastic membrane was preserved in all vessels. Conclusion: This technique is an excellent model to examine the differences between genetically modified mice to clarify the role of putative key molecules in the pathophysiology of restenosis. (orig.) [de

  20. Miocene denudation history of Himalaya deduced from IODP Exp. 354 Bengal Fan

    Science.gov (United States)

    Kohki, Y.; Cruz, J. W.; Osaki, A.; Manoj, M. C.; Hatano, N.; France-Lanord, C.; Spiess, V.; Klaus, A.

    2017-12-01

    The submarine Bengal Fan is the largest submarine fan on Earth and covers the whole Bay of Bengal. The sediments are fed by the Ganges and Brahmaputra rivers reflecting India-Asia plate collision. The sediments recovered from IODP Expedition 354 Bengal Fan record the uplift history of the Himalayan orogenic system. We examined the chemical composition of detrital garnets in the Miocene deposits from Site U1451, where drilling reached to basal horizon of the fan deposits, in order to reveal the detailed denudation history of Himalayan metamorphic rocks. For this purpose, the comparison of chemical composition between detrital garnet in the Bengal Fan deposits and metamorphic garnet in Himalayan metamorphic rocks was carried out. The chemical composition of the metamorphic garnet from Higher Himalayan Crystalline (HHC) in Karnali and Kaligandaki areas, western Nepal, was examined for chemical reference to detrital garnets in Bengal Fan. The metamorphic garnets in "Formation I (Le Fort, 1975)" in HHC are characterized by almandine-rich garnet with high pyrope content. Also, the garnets in "Formation II" are remarked by two types of garnets, i.e., almandine-rich and grandite-rich garnets. Meanwhile, the composition of garnets in "Formation III" is almandine-rich garnet with low pyrope content. In the Bengal Fan deposits, the characteristic garnets, which show the similarity to the metamorphic garnet in HHC, is not found from the Lower Miocene (Burdigalian) deposits. In the Middle and Upper Miocene deposits, the almandine-rich garnets characteristic in Formation I, are normally included. At the basal part of the Middle Miocene (Langhian), almandine-rich garnets with low pyrope content, suggesting the derivation from Formation III, are remarkable. The grandite-rich garnets from Formation II are sporadically found In the Upper Miocene deposits (Tortonian-Messinian). Above chemical comparison between the detrital garnets in Bengal Fan and metamorphic garnets from HHC

  1. Fracture-associated and idiopathic subchondral vertebral lesions: a magnetic resonance study in autopsy specimens with histologic correlation

    International Nuclear Information System (INIS)

    Peters, C.A.; Berg, B.C. vande; Lecouvet, F.E.; Malghem, J.; Galand, C.

    2009-01-01

    The aim of this study was to describe and compare the magnetic resonance (MR) and histological appearance of subchondral vertebral lesions that are idiopathic or that develop with vertebral fractures. T1- and T2-weighted spin-echo images and radiographs were obtained in 81 cadaveric spine specimens. All subchondral vertebral lesions that were considered to be idiopathic or associated with vertebral end plate fractures were selected. Lesions due to growth disturbance were excluded. Radiographs and MR images were analyzed in consensus by two radiologists, and sampled specimens were analyzed by a pathologist. Eleven idiopathic and ten fracture-associated vertebral lesions were available. On T1-weighted images, all lesion signal intensity was low and homogeneous. On T2-weighted images, all idiopathic lesions showed a heterogeneous signal with a central low or intermediate signal component and a peripheral high or intermediate component. All but one fracture-related lesions showed a homogeneous intermediate to high signal intensity. Histological analysis of idiopathic lesions showed a central acellular fibrous connective tissue in all cases surrounded by loose connective tissue in nine cases. Herniated disk material and cartilage metaplasia were found in one lesion only. Fracture-associated lesions contained herniated disk material, necrotic tissue, and loose connective tissue with a peripheral component of loose fibrovascular connective tissue in four cases only. MR and histological appearance of idiopathic and fracture-associated subchondral vertebral lesions differ, suggesting that they might have a different origin. (orig.)

  2. Diagnostic performance of MR imaging in the assessment of subchondral fractures in avascular necrosis of the femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Lee-Ren [E-Da Hospital and I-Shou University, Department of Radiology, Kaohsiung County (China); Chen, Clement K.H.; Pan, Huay-Ben; Yang, Chien-Fang [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (China); National Yang-Ming University, School of Medicine, Taipei (China); Huang, Yi-Luan [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (China)

    2009-06-15

    A prospective study was conducted to determine the accuracy of routine magnetic resonance (MR) imaging in correctly identifying subchondral fracture in avascular necrosis of the femoral head without apparent focal collapse on standard radiographs. Spiral computed tomography (CT) with coronal and sagittal reformations and routine MR imaging with spin-echo T1WI and fat-suppressed spin-echo T2WI coronal, axial, and sagittal images were performed in 28 hips of 25 patients (M/F = 20:5; age 16-76 years) suffering from early-stage avascular necrosis of the femoral head on standard radiographs. The MR images were reviewed by a musculoskeletal radiologist and a general radiologist in blinded fashion. Using CT as the standard of reference, the accuracy of MR imaging in diagnosing subchondral fractures in avascular necrosis was evaluated. When the diagnoses of the two readers were compared with each other, only 16 of the 28 diagnoses (57.5%) agreed. Seventeen of the 28 MR imaging readings (60.7%) made by the musculoskeletal radiologist and 15 of the 28 (53.5%) made by the general radiologist agreed with those of the CT standard. False-positive diagnosis (that is, diagnosis of fracture when no fracture could be seen on CT) was more common than false-negative diagnosis. The accuracy of routine MR imaging in the evaluation of subchondral fracture is not satisfactory. False-positive diagnosis is not uncommon. Interpretation of routine MR imaging readout should be guarded. (orig.)

  3. Diagnostic performance of MR imaging in the assessment of subchondral fractures in avascular necrosis of the femoral head

    International Nuclear Information System (INIS)

    Yeh, Lee-Ren; Chen, Clement K.H.; Pan, Huay-Ben; Yang, Chien-Fang; Huang, Yi-Luan

    2009-01-01

    A prospective study was conducted to determine the accuracy of routine magnetic resonance (MR) imaging in correctly identifying subchondral fracture in avascular necrosis of the femoral head without apparent focal collapse on standard radiographs. Spiral computed tomography (CT) with coronal and sagittal reformations and routine MR imaging with spin-echo T1WI and fat-suppressed spin-echo T2WI coronal, axial, and sagittal images were performed in 28 hips of 25 patients (M/F = 20:5; age 16-76 years) suffering from early-stage avascular necrosis of the femoral head on standard radiographs. The MR images were reviewed by a musculoskeletal radiologist and a general radiologist in blinded fashion. Using CT as the standard of reference, the accuracy of MR imaging in diagnosing subchondral fractures in avascular necrosis was evaluated. When the diagnoses of the two readers were compared with each other, only 16 of the 28 diagnoses (57.5%) agreed. Seventeen of the 28 MR imaging readings (60.7%) made by the musculoskeletal radiologist and 15 of the 28 (53.5%) made by the general radiologist agreed with those of the CT standard. False-positive diagnosis (that is, diagnosis of fracture when no fracture could be seen on CT) was more common than false-negative diagnosis. The accuracy of routine MR imaging in the evaluation of subchondral fracture is not satisfactory. False-positive diagnosis is not uncommon. Interpretation of routine MR imaging readout should be guarded. (orig.)

  4. Hydrogeochemical cycling and chemical denudation in the Fort River Watershed, central Massachusetts: An appraisal of mass-balance studies

    Science.gov (United States)

    Yuretich, Richard F.; Batchelder, Gail L.

    1988-01-01

    The Fort River watershed in central Massachusetts receives precipitation with a composition similar to that in Hubbard Brook (New Hampshire), yet the average stream water chemistry is substantially different, showing higher pH and TDS. This is largely a function of bedrock and surficial geology, and chemical differences among small streams within the Fort River watershed are apparently controlled by the composition and thickness of the prevailing surficial cover. The surficial deposits determine groundwater and surface water flow paths, thereby affecting the resultant contact time with mineral matter and the chemistry of the runoff. Despite the rural setting, over 95% of the annual sodium and chloride in the streams comes from road salt; after correcting for this factor, cation denudation rates are about equal to those at Hubbard Brook. However, silica removal is occurring at a rate more than 30% greater in the Fort River. When climatic conditions in Hubbard Brook and Fort River are normalized, weathering rates appear consistently higher in the Fort River, reflecting differences in weathering processes (i.e., cation exchange and silicate breakdown) and hydrogeology. Because of uncertainties in mechanisms of cation removal from watersheds, the silica denudation rate may be a better index of weathering intensity.

  5. Total glucosides of paeony prevents juxta-articular bone loss in experimental arthritis.

    Science.gov (United States)

    Wei, Chen Chao; You, Fan Tian; Mei, Li Yu; Jian, Sun; Qiang, Chen Yong

    2013-07-21

    Total glucosides of paeony (TGP) is a biologically active compound extracted from Paeony root. TGP has been used in rheumatoid arthritis therapy for many years. However, the mechanism by which TGP prevents bone loss has been less explored. TGP was orally administered for 3 months to New Zealand rabbits with antigen-induced arthritis (AIA). Digital x-ray knee images and bone mineral density (BMD) measurements of the subchondral knee bone were performed before sacrifice. Chondrocytes were observed using transmission electron microscopy (TEM). Histological analysis and mRNA expression of receptor activator of nuclear factor-B ligand (RANKL) and osteoprotegerin (OPG) were evaluated in joint tissues. The BMD value in TGP rabbits was significantly higher compared with that seen in the AIA model rabbits. In addition, the subchondral bone plate was almost completely preserved by TGP treatment, while there was a decrease in bone plate integrity in AIA rabbits. There was less damage to the chondrocytes of the TGP treated group. Immunohistochemical examination of the TGP group showed that a higher percentage of TGP treated chondrocytes expressed OPG as compared to the chondrocytes isolated from AIA treated animals. In contrast, RANKL expression was significantly decreased in the TGP treated group compared to the AIA group. In support of the immunohistochemistry data, the expression of RANKL mRNA was decreased and OPG mRNA expression was enhanced in the TGP group when compared to that of the AIA model group. These results reveal that TGP suppresses juxta-articular osteoporosis and prevents subchondral bone loss. The decreased RANKL and increased OPG expression seen in TGP treated animals could explain how administration of TGP maintains higher BMD.

  6. Metal deposition at the bone-cartilage interface in articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Kaabar, W. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom)], E-mail: w.kaabar@surrey.ac.uk; Daar, E.; Gundogdu, O.; Jenneson, P.M. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Farquharson, M.J. [Department of Radiography, School of Allied Health Sciences, City University, London EC1V 0HB (United Kingdom); Webb, M.; Jeynes, C. [Surrey Ion Beam Centre, University of Surrey, Guildford GU2 7XH (United Kingdom); Bradley, D.A. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2009-03-15

    There is a growing interest being shown in the changes occurring in elemental distribution at the bone-cartilage interface, the changes either being a result of mechanical damage or disease. In particular, such investigations have tended to concern the elemental alterations associated with the osteoarthritic wear and tear damage occurring to the cartilage and subchondral bone of synovial joints or that associated with disease processes such as rheumatic arthritis. Present studies examine sections of femoral head obtained from total hip replacement surgery, use being made of micro-proton-induced X-ray emission ({mu}-PIXE) and the Rutherford back scattering (RBS) techniques. Enhancements of Zn, Ca and P have been observed at the bone-cartilage interface. Further, the concentration of Zn in spongy bone underlying the subchondral surface of a section of the femoral head has been measured, obtaining 136 {mu}g g{sup -1} bone, the presence of Ca and P at the same position being 0.235 and 0.0451 g g{sup -1} bone, respectively. These values are slightly different to figures recently published by other authors using similar techniques.

  7. Progression of cartilage degradation, bone resorption and pain in rat temporomandibular joint osteoarthritis induced by injection of iodoacetate.

    Directory of Open Access Journals (Sweden)

    Xue-Dong Wang

    Full Text Available BACKGROUND: Osteoarthritis (OA is an important subtype of temporomandibular disorders. A simple and reproducible animal model that mimics the histopathologic changes, both in the cartilage and subchondral bone, and clinical symptoms of temporomandibular joint osteoarthritis (TMJOA would help in our understanding of its process and underlying mechanism. OBJECTIVE: To explore whether injection of monosodium iodoacetate (MIA into the upper compartment of rat TMJ could induce OA-like lesions. METHODS: Female rats were injected with varied doses of MIA into the upper compartment and observed for up to 12 weeks. Histologic, radiographic, behavioral, and molecular changes in the TMJ were evaluated by light and electron microscopy, MicroCT scanning, head withdrawal threshold test, real-time PCR, immunohistochemistry, and TUNEL assay. RESULTS: The intermediate zone of the disc loosened by 1 day post-MIA injection and thinned thereafter. Injection of an MIA dose of 0.5 mg or higher induced typical OA-like lesions in the TMJ within 4 weeks. Condylar destruction presented in a time-dependent manner, including chondrocyte apoptosis in the early stages, subsequent cartilage matrix disorganization and subchondral bone erosion, fibrosis, subchondral bone sclerosis, and osteophyte formation in the late stages. Nociceptive responses increased in the early stages, corresponding to severe synovitis. Furthermore, chondrocyte apoptosis and an imbalance between anabolism and catabolism of cartilage and subchondral bone might account for the condylar destruction. CONCLUSIONS: Multi-level data demonstrated a reliable and convenient rat model of TMJOA could be induced by MIA injection into the upper compartment. The model might facilitate TMJOA related researches.

  8. A denuder-impinger system with in situ derivatization followed by gas chromatography-mass spectrometry for the determination of gaseous iodine-containing halogen species.

    Science.gov (United States)

    Huang, Ru-Jin; Hoffmann, Thorsten

    2008-11-14

    Reactive iodine species have been suggested to play an important role in the atmosphere (e.g. tropospheric ozone depletion, coastal new particle formation). However, there still exist major uncertainties about their atmospheric chemistry, mostly due to the lack of analytical approaches for the accurate speciation of certain key compounds. In this study, 1,3,5-trimethoxybenzene (1,3,5-TMB)-coated denuder proved to be suitable for the differentiation between gaseous interhalogens (iodine monochloride (ICl), iodine monobromide (IBr)) and molecular iodine (I2) based on a selective collection/derivatization method. The results of the denuder sampling were compared with the results of impinger sampling in water, methanol and carbon tetrachloride solutions of 1,3,5-TMB. ICl and IBr are converted into 1-iodo-2,4,6-trimethoxybenzene (1-iodo-2,4,6-TMB) and 1-bromo-2,4,6-trimethoxybenzene (1-bromo-2,4,6-TMB), respectively, in the denuder systems. The respective collection efficiency is 99.2% for ICl and 92.6% for IBr, at 500mLmin(-1) gas flow rate. The collection efficiency for I2 is lower than 1% in the same denuder system, but significantly increases to about 90% in the aqueous 1,3,5-TMB loaded impinger. The denuder-impinger coupled system was then used to differentiate and to collect the ICl, IBr and I2 gas mixtures, followed by gas chromatography-ion trap mass spectrometry (GC-MS) determination. The precision of the method is in general better than 9.1%. The parameters affecting denuder operation including sampling flow rate, sampling duration, and relative humidity have been evaluated. The presented method provides an attractive protocol for iodine species analysis for atmospheric chemistry research.

  9. Effects of hyaluronan on three-dimensional microarchitecture of subchondral bone tissues in guinea pig primary osteoarthrosis

    DEFF Research Database (Denmark)

    Ding, M.; Danielsen, Carl Christian; Hvid, Ivan

    2005-01-01

    Activation of spinal cord microglia and astrocytes is a common phenomenon in nerve injury pain models and is thought to exacerbate pain perception. Following a nerve injury, a transient increase in the presence of microglia takes place while the increased numbers of astrocytes stay elevated for a...

  10. Shaping the Australian crust over the last 300 million years: insights from fission track thermotectonic imaging and denudation studies of key terranes

    International Nuclear Information System (INIS)

    Kohn, B.P.; Gleadow, A.J.W.; Brown, R.W.; O'Sullivan, P.B.; Foster, D.A.; Gallagher, K.

    2002-01-01

    Apatite fission track thermochronology is a well-established tool for reconstructing the low-temperature thermal and tectonic evolution of continental crust. The variation of fission track ages and distribution of fission track lengths are primarily controlled by cooling, which may be initiated by earth movements and consequent denudation at the Earth's surface and/or by changes in the thermal regime. Using numerical forward-modelling procedures these parameters can be matched with time-temperature paths that enable thermal and tectonic processes to be mapped out in considerable detail. This study describes extensive Australian regional fission track datasets that have been modelled sequentially and inverted into time-temperature solutions for visualisation as a series of time-slice images depicting the cooling history of present-day surface rocks during their passage through the upper crust. The data have also been combined with other datasets, including digital elevation and heat flow, to image the denudation history and the evolution of palaeo-topography. These images provide an important new perspective on crustal processes and landscape evolution and show how important tectonic and denudation events over the last 300 million years can be visualised in time and space. The application of spatially integrated denudation-rate chronology is also demonstrated for some key Australian terranes including the Lachlan and southern New England Orogens of southeastern Australia, Tasmania, the Gawler Craton, the Mt lsa lnlier, southwestern Australian crystalline terranes (including the Yilgarn Craton) and the Kimberley Block. This approach provides a readily accessible framework for quantifying the otherwise undetectable, timing and magnitude of long-term crustal denudation in these terranes, for a part of the geological record previously largely unconstrained. Discrete episodes of enhanced denudation occurred principally in response to changes in drainage, base

  11. Bone contusions in the adolescent knee: confusion with rupture of anterior cruciate ligament

    International Nuclear Information System (INIS)

    Roca, M.; Mota, J.; Guedea, A.

    1998-01-01

    One of the most specific secondary findings, on magnetic resonance imaging, associated with acute rupture of anterior cruciate ligament (ACL) are bone contusions of lateral femoral condyle or tibial plateau.Given the marked specificity of these indirect findings (97% to 100%), their presence corroborates the diagnosis of ACL tears. The unreliability of these signs in adolescents has recently been reported. We present a case of subchondral bone contusion with intact ACL, the knowledge of which may prevent potential misinterpretations and unnecessary arthroscopic examinations. (Author) 9 refs

  12. Changes in bone marrow lesions in response to weight-loss in obese knee osteoarthritis patients

    DEFF Research Database (Denmark)

    Gudbergsen, Henrik; Boesen, Mikael; Christensen, Robin

    2013-01-01

    Patients are susceptible for knee osteoarthritis (KOA) with increasing age and obesity and KOA is expected to become a major disabling disease in the future. An important feature of KOA on magnetic resonance imaging (MRI) is changes in the subchondral bone, bone marrow lesions (BMLs), which...... are related to the future degeneration of the knee joint as well as prevalent clinical symptoms. The aim of this study was to investigate the changes in BMLs after a 16-week weight-loss period in obese subjects with KOA and relate changes in BMLs to the effects of weight-loss on clinical symptoms....

  13. Bone marrow MR imaging findings in disuse osteoporosis

    International Nuclear Information System (INIS)

    Abreu, Marcelo R. de; Wesselly, Michelle; Chung, Christine B.; Resnick, Donald

    2011-01-01

    To demonstrate MR imaging findings in the cortical and trabecular bone as well as marrow changes in patients with disuse osteoporosis (DO). Sixteen patients (14 men, 2 women, aged 27-86 years) with clinical and radiographic evidence of DO of a lower limb joint (10 knees, 6 ankles) with MR examination of the same joint performed within a 1-month period were selected, as well as 16 healthy volunteers (7 men, 9 women, aged 25-75 years, 10 knees and 6 ankles). MR imaging findings of the bone marrow were analyzed by 2 musculoskeletal radiologists in consensus regarding: diffuse or focal signal alteration, reinforcement of vertical or longitudinal trabecular lines, and presence of abnormal vascularization. All patients (100%,16/16) with DO presented MR imaging abnormalities of the bone marrow, such as: accentuation of vertical trabecular lines (50%, 8/16), presence of subchondral lobules of fat (37.5%, 6/16), presence of horizontal trabecular lines (31%, 5/16), prominence of bone vessels (25%, 4/16), and presence of dotted areas of high signal intensity on T2-weighted fat-suppressed sequences (12.5%, 2/16). Such MR findings did not appear in the control individuals. There are several MR imaging findings in bones with DO that range from accentuation of vertical and horizontal marrow lines, presence of subchondral lobules of fat, prominent bone vascularization and the presence of dotted foci of high signal intensity on T2-weighted fat-suppressed sequences. Recognition of these signs may prove helpful in the identification of DO as well as distinguishing these findings from other entities. (orig.)

  14. Reliability of semiquantitative assessment of osteophytes and subchondral cysts on tomosynthesis images by radiologists with different levels of expertise.

    Science.gov (United States)

    Hayashi, Daichi; Xu, Li; Gusenburg, Jeffrey; Roemer, Frank W; Hunter, David J; Li, Ling; Guermazi, Ali

    2014-01-01

    We aimed to assess reliability of the evaluation of osteophytes and subchondral cysts on tomosynthesis images when read by radiologists with different levels of expertise. Forty subjects aged >40 years had both knees evaluated using tomosynthesis. Images were read by an "experienced" reader (musculoskeletal radiologist with prior experience) and an "inexperienced" reader (radiology resident with no prior experience). Readers graded osteophytes from 0 to 3 and noted the presence/absence of subchondral cysts in four locations of the tibiofemoral joint. Twenty knees were randomly selected and re-read. Inter- and intrareader reliabilities were calculated using overall exact percent agreement and weighted κ statistics. Diagnostic performance of the two readers was compared against magnetic resonance imaging readings by an expert reader (professor of musculoskeletal radiology). The experienced reader showed substantial intrareader reliability for graded reading of osteophytes (90%, κ=0.93), osteophyte detection (95%, κ=0.86) and cyst detection (95%, κ=0.83). The inexperienced reader showed perfect intrareader reliability for cyst detection (100%, κ=1.00) but intrareader reliability for graded reading (75%, κ=0.79) and detection (80%, κ=0.61) of osteophytes was lower than the experienced reader. Inter-reader reliability was 61% (κ=0.72) for graded osteophyte reading, 91% (κ=0.82) for osteophyte detection, and 88% (κ=0.66) for cyst detection. Diagnostic performance of the experienced reader was higher than the inexperienced reader regarding osteophyte detection (sensitivity range 0.74-0.95 vs. 0.54-0.75 for all locations) but diagnostic performance was similar for subchondral cysts. Tomosynthesis offers excellent intrareader reliability regardless of the reader experience, but experience is important for detection of osteophytes.

  15. Cell factory-derived bioactive molecules with polymeric cryogel scaffold enhance the repair of subchondral cartilage defect in rabbits.

    Science.gov (United States)

    Gupta, Ankur; Bhat, Sumrita; Chaudhari, Bhushan P; Gupta, Kailash C; Tägil, Magnus; Zheng, Ming Hao; Kumar, Ashok; Lidgren, Lars

    2017-06-01

    We have explored the potential of cell factory-derived bioactive molecules, isolated from conditioned media of primary goat chondrocytes, for the repair of subchondral cartilage defects. Enzyme-linked immunosorbent assay (ELISA) confirms the presence of transforming growth factor-β1 in an isolated protein fraction (12.56 ± 1.15 ng/mg protein fraction). These bioactive molecules were used alone or with chitosan-agarose-gelatin cryogel scaffolds, with and without chondrocytes, to check whether combined approaches further enhance cartilage repair. To evaluate this, an in vivo study was conducted on New Zealand rabbits in which a subchondral defect (4.5 mm wide × 4.5 mm deep) was surgically created. Starting after the operation, bioactive molecules were injected at the defect site at regular intervals of 14 days. Histopathological analysis showed that rabbits treated with bioactive molecules alone had cartilage regeneration after 4 weeks. However, rabbits treated with bioactive molecules along with scaffolds, with or without cells, showed cartilage formation after 3 weeks; 6 weeks after surgery, the cartilage regenerated in rabbits treated with either bioactive molecules alone or in combinations showed morphological similarities to native cartilage. No systemic cytotoxicity or inflammatory response was induced by any of the treatments. Further, ELISA was done to determine systemic toxicity, which showed no difference in concentration of tumour necrosis factor-α in blood serum, before or after surgery. In conclusion, intra-articular injection with bioactive molecules alone may be used for the repair of subchondral cartilage defects, and bioactive molecules along with chondrocyte-seeded scaffolds further enhance the repair. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  16. The shunt from the cyclooxygenase to lipoxygenase pathway in human osteoarthritic subchondral osteoblasts is linked with a variable expression of the 5-lipoxygenase-activating protein.

    Science.gov (United States)

    Maxis, Kelitha; Delalandre, Aline; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Duval, Nicolas; Lajeunesse, Daniel

    2006-01-01

    Osteoarthritis (OA) is characterized by articular cartilage degradation and hypertrophic bone changes with osteophyte formation and abnormal bone remodeling. Two groups of OA patients were identified via the production of variable and opposite levels of prostaglandin E2 (PGE2) or leukotriene B4 (LTB4) by subchondral osteoblasts, PGE2 levels discriminating between low and high subgroups. We studied whether the expression of 5-lipoxygenase (5-LO) or 5-LO-activating protein (FLAP) is responsible for the shunt from prostaglandins to leukotrienes. FLAP mRNA levels varied in low and high OA groups compared with normal, whereas mRNA levels of 5-LO were similar in all osteoblasts. Selective inhibition of cyclooxygenase-2 (COX-2) with NS-398-stimulated FLAP expression in the high OA osteoblasts subgroup, whereas it was without effect in the low OA osteoblasts subgroup. The addition of PGE2 to the low OA osteoblasts subgroup decreased FLAP expression but failed to affect it in the high OA osteoblasts subgroup. LTB4 levels in OA osteoblasts were stimulated about twofold by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plus transforming growth factor-beta (TGF-beta), a situation corresponding to their effect on FLAP mRNA levels. Treatments with 1,25(OH)2D3 and TGF-beta also modulated PGE2 production. TGF-beta stimulated PGE2 production in both OA osteoblast groups, whereas 1,25(OH)2D3 alone had a limited effect but decreased the effect of TGF-beta in the low OA osteoblasts subgroup. This modulation of PGE2 production was mirrored by the synthesis of COX-2. IL-18 levels were only slightly increased in a subgroup of OA osteoblasts compared with normal; however, no relationship was observed overall between IL-18 and PGE2 levels in normal and OA osteoblasts. These results suggest that the shunt from the production of PGE2 to LTB4 is through regulation of the expression of FLAP, not 5-LO, in OA osteoblasts. The expression of FLAP in OA osteoblasts is also modulated differently by 1,25(OH

  17. Bone Marrow Aspirate Concentrate-Enhanced Marrow Stimulation of Chondral Defects

    Science.gov (United States)

    Eichler, Hermann; Orth, Patrick

    2017-01-01

    Mesenchymal stem cells (MSCs) from bone marrow play a critical role in osteochondral repair. A bone marrow clot forms within the cartilage defect either as a result of marrow stimulation or during the course of the spontaneous repair of osteochondral defects. Mobilized pluripotent MSCs from the subchondral bone migrate into the defect filled with the clot, differentiate into chondrocytes and osteoblasts, and form a repair tissue over time. The additional application of a bone marrow aspirate (BMA) to the procedure of marrow stimulation is thought to enhance cartilage repair as it may provide both an additional cell population capable of chondrogenesis and a source of growth factors stimulating cartilage repair. Moreover, the BMA clot provides a three-dimensional environment, possibly further supporting chondrogenesis and protecting the subchondral bone from structural alterations. The purpose of this review is to bridge the gap in our understanding between the basic science knowledge on MSCs and BMA and the clinical and technical aspects of marrow stimulation-based cartilage repair by examining available data on the role and mechanisms of MSCs and BMA in osteochondral repair. Implications of findings from both translational and clinical studies using BMA concentrate-enhanced marrow stimulation are discussed. PMID:28607559

  18. Pathology of the distal condyles of the third metacarpal and third metatarsal bones of the horse

    International Nuclear Information System (INIS)

    Riggs, C.M.; Whitehouse, G.H.; Boyde, A.

    1999-01-01

    This study examined material from Thoroughbred horses, the majority of which had been in race training, for evidence of pathology in the third metacarpal (McIII) and third metatarsal (MtIII) bones which might be related to the occurrence of distal condylar fractures. Whole bone samples were studied and documented by macrophotography prior to macroradiography and computed tomographic (CT) imaging. Microradiographs were made from 100 microm thick mediolateral sections cut perpendicular to the dorsal and palmar/plantar articular surfaces of distal condylar regions of McIII and MtIII. Blocks were prepared for morphological imaging using the backscattered electron mode of scanning electron microscopy (BSE SEM). Linear defects in mineralised articular cartilage and subchondral bone were found in the palmar/plantar aspects of the condylar grooves adjacent to the sagittal ridge. These were closely related to the pattern of densification of the subchondral bone and were associated with intense focal remodelling of the immediately adjacent and subjacent bone. Parasagittal fractures of the condyles originated in similar defects. A unifying hypothesis for the aetiopathogenesis of these fractures is presented

  19. Mélange versus forearc contributions to sedimentation and uplift, during rapid denudation of a young Banda forearc-continent collisional belt

    NARCIS (Netherlands)

    Duffy, Brendan; Kalansky, Julie; Bassett, Kari; Harris, Ron; Quigley, Mark; van Hinsbergen, Douwe J J; Strachan, Lorna J.; Rosenthal, Yair

    2017-01-01

    New sedimentary geochemistry and petrographic analyses provide the most extensive sedimentary documentation yet of the rapid denudation of the young Timor orogen. The data from three basins including two widely-separated, well-dated sections of the Synorogenic Megasequence of Timor-Leste, and a

  20. A comparison of three terrain parameters that may be used to identify denudation surfaces within a GIS: A case study from Wales, United Kingdom

    Czech Academy of Sciences Publication Activity Database

    Rowberry, Matthew David

    2012-01-01

    Roč. 43, JUN (2012), s. 147-158 ISSN 0098-3004 Institutional research plan: CEZ:AV0Z30460519 Keywords : denudation surfaces * slope angle * relative relief Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.834, year: 2012

  1. Tectonic uplift and denudation rate influence soil chemical weathering intensity in a semi-arid environment, southeast Spain: physico-chemical and mineralogical evidence

    Science.gov (United States)

    Ameijeiras-Mariño, Yolanda; Opfergelt, Sophie; Schoonejans, Jérôme; Vanacker, Veerle; Sonnet, Philippe; Delmelle, Pierre

    2015-04-01

    Tectonic uplift is known to influence denudation rates. Denudation, including chemical weathering and physical erosion, affects soil production rates and weathering intensities. At topographic steady state, weathering can be transport- or weathering-limited. In the transport-limited regime, low denudation rates should lead to comparatively high weathering intensities, while in the weathering-limited case high denudation rates are associated with lower weathering intensities. Here, we test if this relationship applies to semi-arid environments where chemical weathering is generally slow. Three catchments (EST, FIL and CAB) were studied in the Internal Zone of the Betic Cordillera in southeast Spain, spanning a range of increasing uplift rates (10-170 mm/kyr) and increasing denudation rates (20-250 mm/kyr) from EST to CAB. In each catchment, two ridgetop soil profiles were sampled down to the bedrock. The three catchments have similar vegetation and climatic conditions, with precipitation of 250- 315 mm/yr and mean annual temperature of 15-17 °C. The mineralogy of the bedrock, as determined by XRD, is similar across the three catchments and is characterized by the presence of quartz, muscovite, clinochlore, biotite and plagioclase. This primary mineral assemblage is also found in the catchment soils, indicating that the soils studied derive from the same parent material. The soil clay-size fraction is dominated by kaolinite, vermiculite and illite. However, the proportions of the soil primary and secondary minerals vary between the catchment sites. The abundance of biotite decreases from CAB (14%) to EST (4%), whereas the quartz and clay contents show an opposite tendency (from 30 to 69% and 9.9 to 14.3%, respectively). Further, the abundance of vermiculite increases from CAB to EST. The results are interpreted in terms of increasing weathering intensity from CAB to EST by weathering of biotite into vermiculite and enrichment of soils on more weathering resistant

  2. Gross and histological evaluation of early lesions of navicular bone and deep digital flexor tendon in horses

    Directory of Open Access Journals (Sweden)

    Komosa Marcin

    2014-03-01

    Full Text Available The study aimed at evaluation of pathological lesions on flexor surface of navicular bone and deep digital flexor tendon in horses graded in standard X-ray examination as 2 (fair. The evaluation was performed on fifteen horses (6-9 years of age. Analysis procedure involved examining navicular bones on X-ray pictures, post-slaughter preparation of navicular bones from the hoof capsule, macroscopic evaluation of fibrocartilage on flexor surface, and analysis of histologic preparations. In horses with navicular bones graded as 2, early pathological changes have already developed, even if such horses were not lame. The pathological changes included fibrillation and disruption of deep digital flexor tendon surface, loss of fibrocartillage in sagittal ridge area of navicular bone, thinning of subchondral bone on its flexor surface, and fibromyxoid changes in chondroid matrix. In terms of clinical relevance, more studies are needed to understand the sequence of changes in a better way.

  3. Denudation rates of the Southern Espinhaço Range, Minas Gerais, Brazil, determined by in situ-produced cosmogenic beryllium-10

    Science.gov (United States)

    Barreto, Helen N.; Varajão, César A. C.; Braucher, Régis; Bourlès, Didier L.; Salgado, André A. R.; Varajão, Angélica F. D. C.

    2013-06-01

    To investigate denudation rates in the southern part of the Espinhaço Range (central-eastern Brazil) and to understand how this important resistant and residual relief has evolved in the past 1.38 My, cosmogenic 10Be concentrations produced in situ were measured in alluvial sediments from the three main regional basins, whose substratum is composed primarily of quartzites. The long-term denudation rates (up to 1.38 My) estimated from these measurements were compared with those that affect the western (São Francisco River) and eastern (Doce and Jequitinhonha Rivers) basins, which face the West San Francisco craton and the Atlantic, respectively. Denudation rates were measured in 27 samples collected in catchments of different sizes (6-970 km2) and were compared with geomorphic parameters. The mean denudation rates determined in the northern part are low and similar to those determined in the southern part, despite slightly different geomorphic parameter values (catchment relief and mean slope). For the southern catchments, the values are 4.91 ± 1.01 m My- 1 and 3.65 ± 1.26 m My- 1 for the Doce and São Francisco River basins, respectively; for the northern catchments, they are 4.40 ± 1.06 m My- 1 and 3.96 ± 0.91 m My- 1 for the Jequitinhonha and São Francisco River basins, respectively. These low values of denudation rates suggest no direct correlation if plotted against geomorphic parameters such as the catchment area, maximum elevation, catchment relief, average relief and mean slope gradients. These values show that the regional landscape evolves slowly and is strongly controlled by resistant lithology, with similar erosional rates in the three studied basins.

  4. Bone Cancer

    Science.gov (United States)

    Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another ... more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 and ...

  5. Bone Diseases

    Science.gov (United States)

    Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly ... childhood and your teens, your body adds new bone faster than it removes old bone. After about ...

  6. Deep erosions of the palmar aspect of the navicular bone diagnosed by standing magnetic resonance imaging.

    Science.gov (United States)

    Sherlock, C; Mair, T; Blunden, T

    2008-11-01

    Erosion of the palmar (flexor) aspect of the navicular bone is difficult to diagnose with conventional imaging techniques. To review the clinical, magnetic resonance (MR) and pathological features of deep erosions of the palmar aspect of the navicular bone. Cases of deep erosions of the palmar aspect of the navicular bone, diagnosed by standing low field MR imaging, were selected. Clinical details, results of diagnostic procedures, MR features and pathological findings were reviewed. Deep erosions of the palmar aspect of the navicular bone were diagnosed in 16 mature horses, 6 of which were bilaterally lame. Sudden onset of lameness was recorded in 63%. Radiography prior to MR imaging showed equivocal changes in 7 horses. The MR features consisted of focal areas of intermediate or high signal intensity on T1-, T2*- and T2-weighted images and STIR images affecting the dorsal aspect of the deep digital flexor tendon, the fibrocartilage of the palmar aspect, subchondral compact bone and medulla of the navicular bone. On follow-up, 7/16 horses (44%) had been subjected to euthanasia and only one was being worked at its previous level. Erosions of the palmar aspect of the navicular bone were confirmed post mortem in 2 horses. Histologically, the lesions were characterised by localised degeneration of fibrocartilage with underlying focal osteonecrosis and fibroplasia. The adjacent deep digital flexor tendon showed fibril formation and fibrocartilaginous metaplasia. Deep erosions of the palmar aspect of the navicular bone are more easily diagnosed by standing low field MR imaging than by conventional radiography. The lesions involve degeneration of the palmar fibrocartilage with underlying osteonecrosis and fibroplasia affecting the subchondral compact bone and medulla, and carry a poor prognosis for return to performance. Diagnosis of shallow erosive lesions of the palmar fibrocartilage may allow therapeutic intervention earlier in the disease process, thereby preventing

  7. Development and application of denuder sampling techniques with in situ derivatization for the determination of hydrogenbromide in volcanic plumes

    Science.gov (United States)

    Gutmann, Alexandra; Rüdiger, Julian; Hoffmann, Thorsten

    2016-04-01

    The composition of gases in volcanic plumes shifts with subsurface processes inside volcanoes. For monitoring volcanic activity by studying volcanic plumes it is essential to understand the chemical reactions inside the volcanic plume (Bobrowski and Platt, 2013). Measurements of BrO/SO2-ratio already enable insights into magmatic processes (Bobrowski and Giuffrida, 2012). Both, BrO and SO2, are measurable by Remote Sensing Techniques at a safe distance. Models suggest not a direct emission of BrO but formation due to photochemical and multiphase reactions in the gas and particle phase. These model presume HBr as first emitted species (Gerlach, 2004). So HBr is an important connecting link between easily measurable BrO/SO2-ratios and conclusions on a volcanic system. It is of high importance to know if there is a variation in the amount of HBr transformed into BrO and to gain knowledge on the factor of its dependence. Apart from depletion of surrounded ozone also decreasing or depletion of emitted HBr or even HCl could be responsible for the shift (Bobrowski and Giuffrida, 2012). Knowledge about complex processes in volcanic plumes will simplify interpretation and predictions. In this study, first applications of coated gas diffusion denuder (similar to Huang and Hoffmann, 2008) to derivatize gaseous HBr were successful. Due to the lack of adequate remote sensing techniques an in situ method was developed and will be presented in detail. The epoxide of oleic acid was determined as a suitable derivatization agent. The reaction with HBr gives 10-bromo-9-hydroxyoctadecanoic acid. Other hydrogenhalogens give corresponding products. Derivatized analytes were removed from denuder by solvent elution and subsequent analysed with gas chromatography-mass spectrometry. A limit of quantification below 1 ng was achieved. The method was applied on volcanic gas plumes at Mt. Etna in Italy in July and August 2015. The results showed HBr in higher ppt-range. These first proof

  8. Pinhole bone scan mapping of metabolic profiles in osteoarthritis of the knee: a radiographic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. H.; Kim, H. H.; Chung, Y. A.; Chung, S. K.; Bahk, Y. W. [College of Medicine, The Catholic Univ. of Korea, Seoul (Korea, Republic of)

    1999-07-01

    Osteoarthritis (OA) is mixture of damage to a joint and reaction induced therefrom. Heterogeneity, slow change and no proper means of assessing pathology make it a difficult disease to study. Diagnosis can be made by radiography when OA is established. But subtle metabolic change without radiographic alteration can only be detected by bone scan. Present study was performed to assess metabolic profiles of OA of the knee with various radiographic and preradiographic changes using pinhole bone scan (PBS). PBS and radiography were taken at the same time or a few days apart. We used single-head gamma camera and a 4-mm pinhole collimator. Patients were 9 men and 19 women (30-74 yr with mean being 55). PBS was correlated with radiography in each case. Increased tracer uptake was seen in 111 lesions in 28 knees. Intensity was arbitrarily graded into Grade 0-2. The results were divided into group with radiographic change (n=85; Table) and group without (n=26). Generally, tracer uptake was much intense in the sclerotic and cystic form. In radiographically normal group pathological uptake occurred mostly in subchondral bone (n=17) and some in the femoral condyle (n=9) denoting that subchondral bone is the most vulnerable. PBS is sensitive indicator of metabolic alternations in various disease processes of OA in both radiographically normal and abnormal cases.

  9. Review of denudation processes and quantification of weathering and erosion rates at a 0.1 to 1 Ma time scale

    Energy Technology Data Exchange (ETDEWEB)

    Olvmo, Mats (Univ. of Goeteborg, Goeteborg (Sweden). Dept. of Earth Sciences)

    2010-06-15

    The Forsmark and Laxemar areas are quite similar from a geomorphological point of view. Both sites are situated within intact parts of the Sub-Cambrian Peneplain with extremely low relief. The peneplain is considered to be intact at both sites, i.e. the present relief is quite close to the original surface of this old denudation surface. The total amount of glacial erosion up to present is estimated to be relatively low at both sites (less than 10 m on average), but may have been quite important for stripping of old regolith, especially along fracture zones. This is most obvious in the vicinity of the Forsmark site where the dissected coastline 15 km south of the site is interpreted as a result of glacial erosion along old fracture zones. Therefore, from a strict glacial erosion perspective the Laxemar site is somewhat better than Forsmark. However, given the presented long-term denudation up to present, the expected amount of glacial erosion during a future glacial cycle, if similar to the last glacial cycle, is probably very limited for both sites, in the order of 2-5 m. Excluding glacial erosion, the long-term denudation rates of the two sites is fairly low as a consequence of the very low relief and the proximity to base level. The figures estimated for the long term denudation rates are in agreement with reports of denudation rates in shield areas and lie within the range 0 to 10 m/Ma for both sites. A scenario with a five-fold increase of relief that could be the effect of tectonic uplift, in a time perspective considerably longer than the coming 100,000 years, does not significantly change the picture. Even if the local relief is raised to above 100 m at both sites the estimated non-glacial denudation is very low. However, it should be noted that the effect of a relief change on the glacial system is not included in the calculations. Again, such a change on the pattern of glacial erosion would be more pronounced in the Forsmark area, since the coastline is

  10. Review of denudation processes and quantification of weathering and erosion rates at a 0.1 to 1 Ma time scale

    International Nuclear Information System (INIS)

    Olvmo, Mats

    2010-06-01

    The Forsmark and Laxemar areas are quite similar from a geomorphological point of view. Both sites are situated within intact parts of the Sub-Cambrian Peneplain with extremely low relief. The peneplain is considered to be intact at both sites, i.e. the present relief is quite close to the original surface of this old denudation surface. The total amount of glacial erosion up to present is estimated to be relatively low at both sites (less than 10 m on average), but may have been quite important for stripping of old regolith, especially along fracture zones. This is most obvious in the vicinity of the Forsmark site where the dissected coastline 15 km south of the site is interpreted as a result of glacial erosion along old fracture zones. Therefore, from a strict glacial erosion perspective the Laxemar site is somewhat better than Forsmark. However, given the presented long-term denudation up to present, the expected amount of glacial erosion during a future glacial cycle, if similar to the last glacial cycle, is probably very limited for both sites, in the order of 2-5 m. Excluding glacial erosion, the long-term denudation rates of the two sites is fairly low as a consequence of the very low relief and the proximity to base level. The figures estimated for the long term denudation rates are in agreement with reports of denudation rates in shield areas and lie within the range 0 to 10 m/Ma for both sites. A scenario with a five-fold increase of relief that could be the effect of tectonic uplift, in a time perspective considerably longer than the coming 100,000 years, does not significantly change the picture. Even if the local relief is raised to above 100 m at both sites the estimated non-glacial denudation is very low. However, it should be noted that the effect of a relief change on the glacial system is not included in the calculations. Again, such a change on the pattern of glacial erosion would be more pronounced in the Forsmark area, since the coastline is

  11. Technetium 99m methylene diphosphonate bone scanning in osteoarthritic hands

    International Nuclear Information System (INIS)

    Buckland-Wright, J.C.; Lynch, J.A.; Macfarlane, D.G.; Homoeopathic Hospital, Tunbridge; Fogelman, I.; Emery, P.

    1991-01-01

    In this prospective study, the radiological features characteristic of osteoarthritis of the hand were compared with the radionuclide bone scan images. A total of 32 patients was assessed at 6-monthly intervals for 18 months. Microfocal radiographs were taken at each visit. The high magnification and resolution of this technique permitted direct measurement of joint space width, subchondral sclerosis, osteophyte number and area and juxta-articular radiolucency area for each joint in the hand. Four-hour technetium 99m methylene diphosphonate bone scans were taken at 0 and 12 months and the activity of tracer uptake at each joint scored. The latter was compared with each X-radiographic feature at every visit and the changes between visits analysed. The scan scores did not correlate with any of the X-radiographic features other than osteophyte size. During the study the size of growing and remodelling osteophytes increased significantly at joints with raised or increased isotope uptake. (orig.)

  12. Technetium 99m methylene diphosphonate bone scanning in osteoarthritic hands

    Energy Technology Data Exchange (ETDEWEB)

    Buckland-Wright, J.C.; Lynch, J.A. (United Medical and Dental Schools of Guy' s and Saint Thomas' , London (UK). Dept. of Anatomy); Macfarlane, D.G. (United Medical and Dental Schools of Guy' s and Saint Thomas' , London (UK). Dept. of Anatomy Homoeopathic Hospital, Tunbridge (UK). Dept. of Rheumatology); Fogelman, I. (United Medical and Dental Schools of Guy' s and Saint Thomas' , London (UK). Dept. of Nuclear Medicine); Emery, P. (United Medical and Dental Schools of Guy' s and Saint Thomas' , London (UK). Dept. of Rheumatology)

    1991-01-01

    In this prospective study, the radiological features characteristic of osteoarthritis of the hand were compared with the radionuclide bone scan images. A total of 32 patients was assessed at 6-monthly intervals for 18 months. Microfocal radiographs were taken at each visit. The high magnification and resolution of this technique permitted direct measurement of joint space width, subchondral sclerosis, osteophyte number and area and juxta-articular radiolucency area for each joint in the hand. Four-hour technetium 99m methylene diphosphonate bone scans were taken at 0 and 12 months and the activity of tracer uptake at each joint scored. The latter was compared with each X-radiographic feature at every visit and the changes between visits analysed. The scan scores did not correlate with any of the X-radiographic features other than osteophyte size. During the study the size of growing and remodelling osteophytes increased significantly at joints with raised or increased isotope uptake. (orig.).

  13. Effect of occlusal (mechanical) stimulus on bone remodelling in rat mandibular condyle.

    Science.gov (United States)

    Gazit, D; Ehrlich, J; Kohen, Y; Bab, I

    1987-09-01

    Mechanical load influences the remodelling of skeletal tissues. In the mandibular condyle, occlusal alterations and the consequent mechanical stimulus induce changes in chondrocytes and cartilage mineralization. In the present study we quantified in the mandibular condyle the effect of occlusal interference on remodelling of the subchondral bone. Computerized histomorphometry after 5-21-day exposure to the influence of a unilateral occlusal splint revealed an increased rate of trabecular remodelling, consisting of enhancement in osteoblast and osteoclast numbers and activities. The bone formation parameters reached their high values on Days 5 or 9 and remained stable thereafter. Bone resorption showed a gradual increase throughout the experimental period. These results further characterize the temporomandibular joint reaction to occlusal alterations. It is suggested that the present increase in bone turnover together with the known enhancement in chondrogenesis are part of a process of functional adaptation in response to mechanical stimulus.

  14. Modes and implications of mantle and lower-crust denudation at slow-spreading mid-ocean ridges

    Science.gov (United States)

    Schroeder, Timothy John

    Slow-spreading mid-ocean ridges (Cann, 1993, Cannat, 1993). Extension at mid-ocean ridges is most commonly manifested by slip on high angle (˜60°) normal faults that dip into, and define the rift valley walls (Smith and Cann, 1993). Less commonly, extension occurs by long periods of slip along low-angle normal faults that penetrate to structurally deep levels of oceanic lithosphere and denude gabbro and/or pendotite to the seafloor in domal massifs termed "oceanic core complexes" (Dick et al., 1981; Dick et al., 1991; Tucholke et al., 1998; Mutter and Karson, 1992; Cann et al., 1997; MacLeod et al., 2002). This dissertation addresses processes and implications of tectonic extension at two oceanic core complexes. Atlantis Massif (30°N, Mid-Atlantic Ridge) is formed dominantly of serpentinized peridotite with lesser gabbro, and Atlantis Bank (57°E, Southwest Indian Ridge) is dominated by gabbro. Localization of brittle strain at Atlantis Massif occurred by reaction-softening processes associated with metasomatic alteration of peridotite and serpentmite to amphibole-, chlorite- and talc-bearing assemblages. Ductile strain at Atlantis Massif and Atlantis Bank is localized into intervals of highly-fractionated, oxide-rich gabbro. Two-oxide geothermometry of gabbro indicates that it was not penetratively deformed below ˜500°C. Denuded peridotite at Atlantis Massif is host to hydrothermal circulation driven in part by exothermic serpentinization reactions. Serpentinization decreases the seismic velocity of peridotite and leads to acquisition of a magnetic signature. Venting of highly-alkaline, methane- and hydrogen-rich serpentinization-derived fluids leads to lithification of seafloor carbonate ooze by precipitation of carbonate cement in a zone of mixing with "normal" seawater. This process may be the primary depositional mechanism of ophicalcite deposits and likely occurs wherever peridotite is exposed near the Earth's surface and is fractured to permit water

  15. Cooling and denudation history of the Tsuruga body of Kojaku granite, southwest Japan, constrained from multi-system thermochronology

    International Nuclear Information System (INIS)

    Sueoka, Shigeru; Shimada, Koji; Ishimaru, Tsuneari; Umeda, Koji; Yasue, Ken-ichi; Niwa, Masakazu; Danhara, Tohru; Iwano, Hideki; Yagi, Koshi

    2016-01-01

    In this study, multi-system thermochronology, i.e., fission-track (FT), K-Ar and U-Pb methods are used to identify the cooling and denudation history of the Tsuruga body of Kojaku granite, southwest Japan. Apatite FT age of 51.8 ± 6.5 Ma, zircon FT age of 70.4 ± 2.0 Ma, biotite K-Ar ages of 66.7–62.0 Ma, and zircon U-Pb age of 68.5 ± 0.7 Ma were obtained for granitic samples, whereas plagioclase K-Ar ages of 19.1–18.8 Ma and whole-rock K-Ar age of 19.0 ± 2.9 Ma were inferred for the basaltic dyke intruding into the granite. The zircon FT lengths are not significantly shorter than their initial lengths, implying rapid cooling at the zircon FT partial annealing zone (PAZ). On the other hand, the apatite FT length distribution shows a typical pattern for granitic pluton without reheating, indicating a slow cooling history at the apatite FT PAZ. Based on the results of these thermochronometric analyses, inverse thermal calculations using the FT data, and simple thermal conduction modeling of the granitic body, the cooling and denudation histories of the Tsuruga body are reconstructed: (1) the Tsuruga body intruded at ca. 68 Ma, late Cretaceous, at a depth of several kilometers, (2) rapidly cooled to below the zircon FT PAZ by heat conduction within a few million years or less, and (3) slowly cooled due to peneplanation during the past 50–60 million years. On the other hand, the whole-rock Rb-Sr age previously reported for the Kojaku body is younger than when the cooling curve of the Tsuruga body obtained by this study intersects with the closure temperature of the whole-rock Rb-Sr system. This may imply a time lag between the formation ages of these bodies, but more thermochronometric studies are required to draw a definitive conclusion. The K-Ar ages of the basaltic dyke are interpreted as its formation age, indicating that dyke intrusion was associated with the Green Tuff movement. (author)

  16. Identification of trabecular excrescences, novel microanatomical structures, present in bone in osteoarthropathies

    Directory of Open Access Journals (Sweden)

    AM Taylor

    2012-04-01

    Full Text Available It is widely held that bone architecture is finely regulated in accordance with homeostatic requirements. Aberrant remodelling (hyperdensification and/or cyst formation in the immediately subchondral region has previously been described in bone underlying cartilage in arthropathies. The present study examined the trabecular architecture of samples of bone, initially in the severe osteoarthropathy of alkaptonuria, but subsequently in osteoarthritis using a combination of light microscopy, 3D scanning electron microscopy and quantitative backscattered electron scanning electron microscopy. We report an extraordinary and previously unrecognised bone phenotype in both disorders, including novel microanatomical structures. The underlying subchondral trabecular bone contained idiosyncratic architecture. Trabecular surfaces had numerous outgrowths that we have termed "trabecular excrescences", of which three distinct types were recognised. The first type arose from incomplete resorption of branching secondary trabeculae arising from the deposition of immature (woven bone in prior marrow space. These were characterised by very deeply scalloped surfaces and rugged edges. The second type had arisen in a similar way but been smoothed over by new bone deposition. The third type, which resembled coarse stucco, probably arises from resting surfaces that had been focally reactivated. These were poorly integrated with the prior trabecular wall. We propose that these distinctive microanatomical structures are indicative of abnormal osteoclast/osteoblast modelling in osteoarthropathies, possibly secondary to altered mechanical loading or other aberrant signalling. Identification of the mechanisms underlying the formation of trabecular excrescences will contribute to a better understanding of the role of aberrant bone remodelling in arthropathies and development of new therapeutic strategies.

  17. Fresh osteochondral allografts in the knee: comparison of primary transplantation versus transplantation after failure of previous subchondral marrow stimulation.

    Science.gov (United States)

    Gracitelli, Guilherme C; Meric, Gokhan; Briggs, Dustin T; Pulido, Pamela A; McCauley, Julie C; Belloti, João Carlos; Bugbee, William D

    2015-04-01

    In most treatment algorithms, osteochondral allograft (OCA) transplantation is regarded as an alternative salvage procedure when other, previous reparative treatments have failed. To compare the outcomes of a retrospective matched-pair cohort of (1) primary OCA transplantation and (2) OCA transplantation after failure of previous subchondral marrow stimulation. Cohort study; Level of evidence, 3. An OCA database was used to identify 46 knees that had OCA transplantation performed as a primary treatment (group 1) and 46 knees that underwent OCA transplantation after failure of previous subchondral marrow stimulation (group 2). All patients had a minimum of 2 years' follow-up. Patients in each group were matched for age (±5 years), diagnosis (osteochondral lesion, degenerative chondral lesion, traumatic chondral injury), and graft size (small, 10 cm2). The groups had similar body mass indexes, sex distributions, and graft locations (femoral condyle, patella, and trochlea. The number and type of further surgeries after the OCA transplantation were assessed; failure was defined as any reoperation resulting in removal of the graft. Functional outcomes were evaluated by use of the modified Merle d'Aubigné-Postel (18-point) scale, International Knee Documentation Committee (IKDC) subjective knee evaluation form, Knee injury and Osteoarthritis Outcomes Score (KOOS), and the Knee Society function (KS-F) scale. Patient satisfaction, according to a 5-point scale from "extremely satisfied" to "dissatisfied," was recorded at the latest follow-up. Eleven of 46 knees (24%) in group 1 had reoperations, compared with 20 of 46 knees (44%) in group 2 (P = .04). The OCA was classified as a failure in 5 knees (11%) in group 1 and 7 knees (15%) in group 2 (P = .53). At 10 years of follow-up, survivorship of the graft was 87.4% and 86% in groups 1 and 2, respectively. Both groups showed improvement in pain and function on all subjective scores from preoperatively to the latest follow

  18. Extensive Evaluation of a Diffusion Denuder Technique for the Quantification of Atmospheric Stable and Radioactive Molecular Iodine

    DEFF Research Database (Denmark)

    Huang, Ru-Jin; Hou, Xiaolin; Hoffmann, Thorsten

    2010-01-01

    In this paper we present the evaluation and optimization of a new approach for the quantification of gaseous molecular iodine (I2) for laboratory- and field-based studies and its novel application for the measurement of radioactive molecular iodine. α-Cyclodextrin (α-CD) in combination with 129I......, and condition of release and derivatization of iodine, is extensively evaluated and optimized. The collection efficiency is larger than 98% and the limit of detection (LOD) obtained is 0.17 parts-per-trillion-by-volume (pptv) for a sampling duration of 30 min at 500 mL min−1. Furthermore, the potential use...... of this protocol for the determination of radioactive I2 at ultra trace level is also demonstrated when 129I− used in the coating is replaced by 127I− and a multiple denuder system is used. Using the present method we observed 25.7−108.6 pptv 127I2 at Mweenish Bay, Ireland and 108 molecule m−3 129I2 at Mainz...

  19. Structural variation of the distal condyles of the third metacarpal and third metatarsal bones in the horse

    International Nuclear Information System (INIS)

    Riggs, C.M.; Whitehouse, G.H.; Boyde, A.

    1999-01-01

    This study examined 3-dimensional (3D) distribution of sectors with contrasting density in the equine third metacarpal (McIII) and third metatarsal (MtIII) bones with a view to explaining the aetiology of distal condylar fractures. Macroradiography and computed tomographic (CT) imaging were used in the nondestructive study of bones obtained from horses, most of which were Thoroughbreds in race training. Distal condylar regions of McIII and MtIII were also studied in microradiographs of 100 mu m thick mediolateral sections cut perpendicular to the dorsal and palmar/plantar articular surfaces. Qualitative and quantitative results from all methods used (radiography, CTand microradiographic stereology) demonstrated densification (sclerosis) of subchondral bone located in the palmar/plantar regions of the medial and lateral condyles of both McIII and MtIII, Substantial density gradients between the denser condyles and the subchondral bone of the sagittal groove were shown to equate with anatomical differences in loading intensity during locomotion. It is hypothesised that such differences in bone density results in stress concentration at the palmar/plantar aspect of the condylar grooves, which may predispose to fracture

  20. Association between disk position and degenerative bone changes of the temporomandibular joints: an imaging study in subjects with TMD.

    Science.gov (United States)

    Cortés, Daniel; Sylvester, Daniel Cortés; Exss, Eduardo; Marholz, Carlos; Millas, Rodrigo; Moncada, Gustavo

    2011-04-01

    The aim of this study was to determine the frequency and relationship between disk position and degenerative bone changes in the temporomandibular joints (TMJ), in subjects with internal derangement (ID). MRI and CT scans of 180 subjects with temporomandibular disorders (TMD) were studied. Different image parameters or characteristics were observed, such as disk position, joint effusion, condyle movement, degenerative bone changes (flattened, cortical erosions and irregularities), osteophytes, subchondral cysts and idiopathic condyle resorption. The present study concluded that there is a significant association between disk displacement without reduction and degenerative bone changes in patients with TMD. The study also found a high probability of degenerative bone changes when disk displacement without reduction is present. No association was found between TMD and condyle range of motion, joint effusion and/or degenerative bone changes. The following were the most frequent morphological changes observed: flattening of the anterior surface of the condyle; followed by erosions and irregularities of the joint surfaces; flattening of the articular surface of the temporal eminence, subchondral cysts, osteophytes; and idiopathic condyle resorption, in decreasing order.

  1. Galloping exercise induces regional changes in bone density within the third and radial carpal bones of Thoroughbred horses

    International Nuclear Information System (INIS)

    Firth, E.C.; Delahunt, J.; Wichtel, J.W.; Birch, H.L.; Goodship, A.E.

    1999-01-01

    This study was performed to test the hypothesis that a localised bone hypertrophy could occur within the subchondral cancellous architecture of the third and radial carpal bones. Using 2 levels of controlled and defined exercise, it was observed that a high intensity treadmill exercise protocol resulted in functional adaptation of the carpal bones. The increase in trabecular thickening and density was seen to be localised to those regions underlying common sites of cartilage degradation, the interface of the thickened trabeculae with the normal architecture in the third carpal hone was coincident with a common site of clinical fractures. The bone changes were determined both qualitatively on examination of slab radiographs and quantified by dual energy x-ray absorptiometry. The findings from this study are relevant to mechanical factors involved in the pathophysiology of joint degeneration. The potential clinical implications of this study are in relation to changes in the type and duration of exercise regimens used in training of equine athletes. The rapid response of bone to mechanical stimulation has implications in the longer term for localised cartilage degradation. Imaging techniques could be developed to monitor these early bone changes in the specific areas identified in this study and thus allow appropriate changes in training intensity to minimise subsequent damage to the articular surface

  2. Bioactive glass 13-93 as a subchondral substrate for tissue-engineered osteochondral constructs: a pilot study.

    Science.gov (United States)

    Jayabalan, Prakash; Tan, Andrea R; Rahaman, Mohammed N; Bal, B Sonny; Hung, Clark T; Cook, James L

    2011-10-01

    Replacement of diseased areas of the joint with tissue-engineered osteochondral grafts has shown potential in the treatment of osteoarthritis. Bioactive glasses are candidates for the osseous analog of these grafts. (1) Does Bioactive Glass 13-93 (BG 13-93) as a subchondral substrate improve collagen and glycosaminoglycan production in a tissue-engineered cartilage layer? (2) Does BG 13-93 as a culture medium supplement increase the collagen and glycosaminoglycan production and improve the mechanical properties in a tissue-engineered cartilage layer? In Study 1, bioactive glass samples (n = 4) were attached to a chondrocyte-seeded agarose layer to form an osteochondral construct, cultured for 6 weeks, and compared to controls. In Study 2, bioactive glass samples (n = 5) were cocultured with cell-seeded agarose for 6 weeks. The cell-seeded agarose layer was exposed to BG 13-93 either continuously or for the first or last 2 weeks in culture or had no exposure. Osteochondral constructs with a BG 13-93 base had improved glycosaminoglycan deposition but less collagen II content. Agarose scaffolds that had a temporal exposure to BG 13-93 within the culture medium had improved mechanical and biochemical properties compared to continuous or no exposure. When used as a subchondral substrate, BG 13-93 did not improve biochemical properties compared to controls. However, as a culture medium supplement, BG 13-93 improved the biochemical and mechanical properties of a tissue-engineered cartilage layer. BG 13-93 may not be suitable in osteochondral constructs but could have potential as a medium supplement for neocartilage formation.

  3. Bone marrow aspiration

    Science.gov (United States)

    Iliac crest tap; Sternal tap; Leukemia - bone marrow aspiration; Aplastic anemia - bone marrow aspiration; Myelodysplastic syndrome - bone marrow aspiration; Thrombocytopenia - bone marrow aspiration; Myelofibrosis - bone marrow aspiration

  4. Low Bone Density

    Science.gov (United States)

    ... Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone density ... people with normal bone density. Detecting Low Bone Density A bone density test will determine whether you ...

  5. Qualitative assessment of bone density at the distal articulating surface of the third metacarpal in Thoroughbred racehorses with and without condylar fracture.

    Science.gov (United States)

    Loughridge, A B; Hess, A M; Parkin, T D; Kawcak, C E

    2017-03-01

    Changes in subchondral bone density, induced by the repetitive cyclical loading of exercise, may potentiate fatigue damage and the risk of fracture. To use computed tomography (CT) to characterise bone density patterns at the articular surface of the third metacarpal bone in racehorses with and without lateral condylar fractures. Case control METHODS: Computed tomographic images of the distal articulating surface of the third metacarpal bone were obtained from Thoroughbred racehorses subjected to euthanasia in the UK. Third metacarpal bones were divided into 3 groups based on lateral condyle status; fractured (FX, n = 42), nonfractured contralateral condyle (NFX, n = 42) and control condyles from horses subjected to euthanasia for reasons unrelated to the third metacarpal bone (control, n = 94). Colour CT images were generated whereby each colour represented a range of pixel values and thus a relative range of bone density. A density value was calculated qualitatively by estimating the percentage of each colour within a specific region. Subchondral bone density was assessed in 6 regions from dorsal to palmar and 1 mm medial and lateral to the centre of the lateral parasagittal groove in NFX and control condyles and 1 mm medial and lateral to the fracture in FX condyles. Bone density was significantly higher in the FX and NFX condyles compared with control condyles for all 6 regions. A significantly higher bone density was observed in FX condyles relative to NFX condyles in the lateral middle and lateral palmar regions. Fractured condyles had increased heterogeneity in density among the 6 regions of interest compared with control and NFX condyles. Adjacent to the fracture, a focal increase in bone density and increased heterogeneity of density were characteristic of limbs with lateral condylar fractures compared with control and NFX condyles. These differences may represent pathological changes in bone density that increase the risk for lateral condylar fractures in

  6. Bone tumors

    International Nuclear Information System (INIS)

    Moylan, D.J.; Yelovich, R.M.

    1991-01-01

    Primary bone malignancies are relatively rare with less than 4,000 new cases per year. Multiple myeloma (more correctly a hematologic malignancy) accounts for 40%; osteosarcomas, 28%; chondrosarcomas, 13%; fibrosarcomas arising in bone, 4%; and Ewing's sarcoma, 7%. The authors discuss various treatments for bone tumors, including radiotherapy, chemotherapy and surgery

  7. Histological Features of the Distal Third Metacarpal Bone in Thoroughbred Racehorses, With and Without Lateral Condylar Fractures.

    Science.gov (United States)

    Pinilla, M J; Tranquille, C A; Blunden, A S; Chang, Y M; Parkin, T D H; Murray, R C

    2017-07-01

    A detailed histopathological study of the distal third metacarpal bone of Thoroughbred racehorses was undertaken to characterize lesions observed previously on magnetic resonance imaging (MRI). The bones were selected and grouped on the basis of MRI features. Representative sections in different planes were processed for histopathology. All lesions observed in the articular cartilage (AC) and subchondral bone (SCB) were recorded and graded with a scoring system, based partially on the Osteoarthritis Research Society International grading system. The scoring system included the severity of the lesion. Descriptive statistics and linear mixed effects models were performed. A positive correlation was observed between the severity of histopathological changes in the superficial and deeper osteochondral tissues, and between the number of race starts and AC score. Age was not correlated with AC or SCB score. A moderate variation in AC and SCB scores was observed between the groups; however, there were differences within individual bones. Bones with focal palmar necrosis (FPN) showed significant differences in the histological scoring of the AC compared with bones without FPN. Bones with incomplete fractures or larger areas of bone remodelling showed significant differences in SCB pathology when compared with bones with FPN. Haematoidin was detected in areas with excessive SCB and cancellous bone sclerosis and/or irregular bone density. This finding is suggestive of poor blood perfusion in these areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Development of a coupled diffusion denuder system combined with gas chromatography/mass spectrometry for the separation and quantification of molecular iodine and the activated iodine compounds iodine monochloride and hypoiodous acid in the marine atmosphere.

    Science.gov (United States)

    Huang, Ru-Jin; Hoffmann, Thorsten

    2009-03-01

    This study concerns the development of a coupled diffusion denuder system capable of separating and quantifying gaseous molecular iodine (I(2)) and two other highly reactive iodine species, ICl and HOI, which are collectively named activated iodine compounds (AIC). Both I(2) and AIC are key species in the atmospheric chemistry of iodine. 1,3,5-Trimethoxybenzene (1,3,5-TMB)- and alpha-cyclodextrin/(129)I(-) (alpha-CD/(129)I(-))-coated denuders proved to be suitable for the collection of gaseous AIC and I(2), respectively. The experimental collection efficiencies for AIC (tested as ICl) and I(2) agreed well with the theoretical values for gas flow rates in the range between 300 and 1800 mL min(-1). The coupled denuder system (1,3,5-TMB-coated denuder as front-denuder coupled upstream of an alpha-CD/(129)I(-)-coated denuder) was applied successfully to separate test gas mixtures of ICl and I(2) at various mixing ratios in the laboratory. The operation of both denuder systems was demonstrated to be independent of relative humidity (0-100%) and storage period (at least 2 weeks prior to and after sampling). Detection limits were achieved at sub-parts-per-trillion-by-volume (sub-pptv) level. The presented method provides a reliable and practical approach for the speciation of gaseous iodine compounds. In addition, we report for the first time ambient air measurements of AIC mixing ratios, carried out at the atmospheric research station in Mace Head, Ireland. A maximum concentration of AIC of 30.2 pptv was observed for nighttime measurements and 6.0 pptv for daytime measurements. A similar diurnal pattern was found for I(2) with an average concentration level of 23.2 pptv during daytime and 85.1 pptv during nighttime, indicating a strong correlation with AIC.

  9. Bone banking.

    Science.gov (United States)

    Howard, W

    1999-04-01

    The use of human organs and tissues for transplantation in Australia has increased significantly over the past 30 years. In 1997, the Australian Coordinating Committee on Organ Registries and Donation (ACCORD) reported a total number of 190 organ donors, 636 corneal donors and 1509 bone donors Australia wide. Of the 1509 bone donations, 143 came from cadaveric sources and 1366 were made by living donors. Bone transplantation is not as widely recognised as solid organ or corneal transplantation. Due to improved technology and surgical skills, the demand for bone transplantation has increased markedly. This Clinical Update will provide an overview of the physiological aspects of bone transplantation and explore bone banking, a key step in the complex and critical process of bone transplantation.

  10. Inhibition of PKC-dependent extracellular Ca2+ entry contributes to the depression of contractile activity in long-term pressure-overloaded endothelium-denuded rat aortas

    International Nuclear Information System (INIS)

    Padilla, J.; López, R.M.; López, P.; Castillo, M.C.; Querejeta, E.; Ruiz, A.; Castillo, E.F.

    2014-01-01

    We examined the contractile responsiveness of rat thoracic aortas under pressure overload after long-term suprarenal abdominal aortic coarctation (lt-Srac). Endothelium-dependent angiotensin II (ANG II) type 2 receptor (AT 2 R)-mediated depression of contractions to ANG II has been reported in short-term (1 week) pressure-overloaded rat aortas. Contractility was evaluated in the aortic rings of rats subjected to lt-Srac or sham surgery (Sham) for 8 weeks. ANG I and II levels and AT 2 R protein expression in the aortas of lt-Srac and Sham rats were also evaluated. lt-Srac attenuated the contractions of ANG II and phenylephrine in the aortas in an endothelium-independent manner. However, lt-Srac did not influence the transient contractions induced in endothelium-denuded aortic rings by ANG II, phenylephrine, or caffeine in Ca 2+ -free medium or the subsequent tonic constrictions induced by the addition of Ca 2+ in the absence of agonists. Thus, the contractions induced by Ca 2+ release from intracellular stores and Ca 2+ influx through stored-operated channels were not inhibited in the aortas of lt-Srac rats. Potassium-elicited contractions in endothelium-denuded aortic rings of lt-Srac rats remained unaltered compared with control tissues. Consequently, the contractile depression observed in aortic tissues of lt-Srac rats cannot be explained by direct inhibition of voltage-operated Ca 2+ channels. Interestingly, 12-O-tetradecanoylphorbol-13-acetate-induced contractions in endothelium-denuded aortic rings of lt-Srac rats were depressed in the presence but not in the absence of extracellular Ca 2+ . Neither levels of angiotensins nor of AT 2 R were modified in the aortas after lt-Srac. The results suggest that, in rat thoracic aortas, lt-Srac selectively inhibited protein kinase C-mediated activation of contraction that is dependent on extracellular Ca 2+ entry

  11. Bone development

    DEFF Research Database (Denmark)

    Tatara, M.R.; Tygesen, Malin Plumhoff; Sawa-Wojtanowicz, B.

    2007-01-01

    The objective of this study was to determine the long-term effect of alpha-ketoglutarate (AKG) administration during early neonatal life on skeletal development and function, with emphasis on bone exposed to regular stress and used to serve for systemic changes monitoring, the rib. Shropshire ram.......01). Furthermore, AKG administration induced significantly higher bone mineral density of the cortical bone by 7.1% (P

  12. Effects of long-term estrogen replacement therapy on bone turnover in periarticular tibial osteophytes in surgically postmenopausal cynomolgus monkeys.

    Science.gov (United States)

    Olson, Erik J; Lindgren, Bruce R; Carlson, Cathy S

    2008-05-01

    The aims of the present study were to assess the effects of long-term estrogen replacement therapy (ERT) on size and indices of bone turnover in periarticular osteophytes in ovariectomized cynomolgus monkeys and to compare dynamic indices of bone turnover in osteophyte bone with those of subchondral bone (SCB) and epiphyseal/metaphyseal cancellous (EMC) bone. One hundred sixty-five adult female cynomolgus macaques were bilaterally ovariectomized and randomly divided into three age- and weight-matched treatment groups for a 36-month treatment period. Group 1 (OVX control) received no treatment, Group 2 (SPE) received soy phytoestrogens, and Group 3 (ERT) received conjugated equine estrogens in the diet; all monkeys were labeled with calcein before necropsy. A midcoronal, plastic-embedded section of the right proximal tibia from 20 randomly selected animals per treatment group was examined histologically. Forty-nine of the sections (OVX control, n=16; SPE, n=16; ERT, n=17) contained lateral abaxial osteophytes, and static and dynamic histomorphometry measurements were taken from osteophyte bone, SCB from the lateral tibial plateau, and EMC bone. Data were analyzed using the ANOVA and Kruskal-Wallis test, correlation and regression methods, and the Friedman and Wilcoxon signed rank test. There was no significant effect of long-term ERT on osteophyte area or on any static or dynamic histomorphometry parameters. The bone volume, trabecular number, and trabecular thickness in osteophyte bone were considerably higher than in EMC bone; whereas, trabecular separation was considerably lower in osteophyte bone. In all three treatment groups, BS/BV was significantly lower in osteophyte bone vs. EMC bone and significantly higher in osteophyte bone vs. lateral SCB. We conclude that osteophyte area and static and dynamic histomorphometry parameters within periarticular tibial osteophytes in ovariectomized cynomolgus monkeys are not significantly influenced by long-term ERT, but

  13. Effects of long-term estrogen replacement therapy on bone turnover in periarticular tibial osteophytes in surgically postmenopausal cynomolgus monkeys

    Science.gov (United States)

    Olson, Erik J.; Lindgren, Bruce R.; Carlson, Cathy S.

    2008-01-01

    The aims of the present study were to assess the effects of long-term estrogen replacement therapy (ERT) on size and indices of bone turnover in periarticular osteophytes in ovariectomized cynomolgus monkeys and to compare dynamic indices of bone turnover in osteophyte bone with those of subchondral bone (SCB) and epiphyseal/metaphyseal cancellous (EMC) bone. One hundred sixty-five adult female cynomolgus macaques were bilaterally ovariectomized and randomly divided into three age- and weight-matched treatment groups for a 36-month treatment period. Group 1 (OVX control) received no treatment, Group 2 (SPE) received soy phytoestrogens, and Group 3 (ERT) received conjugated equine estrogens in the diet; all monkeys were labeled with calcein before necropsy. A midcoronal, plastic-embedded section of the right proximal tibia from 20 randomly selected animals per treatment group was examined histologically. Forty-nine of the sections (OVX control, n=16; SPE, n=16; ERT, n=17) contained lateral abaxial osteophytes, and static and dynamic histomorphometry measurements were taken from osteophyte bone, SCB from the lateral tibial plateau, and EMC bone. Data were analyzed using the ANOVA and Kruskal-Wallis test, correlation and regression methods, and the Friedman and Wilcoxon signed rank test. There was no significant effect of long-term ERT on osteophyte area or on any static or dynamic histomorphometry parameters. The bone volume, trabecular number, and trabecular thickness in osteophyte bone were considerably higher than in EMC bone; whereas, trabecular separation was considerably lower in osteophyte bone. In all three treatment groups, BS/BV was significantly lower in osteophyte bone vs. EMC bone and significantly higher in osteophyte bone vs. lateral SCB. We conclude that osteophyte area and static and dynamic histomorphometry parameters within periarticular tibial osteophytes in ovariectomized cynomolgus monkeys are not significantly influenced by long-term ERT, but

  14. Proteinase-activated receptor 2 modulates OA-related pain, cartilage and bone pathology.

    Science.gov (United States)

    Huesa, Carmen; Ortiz, Ana C; Dunning, Lynette; McGavin, Laura; Bennett, Louise; McIntosh, Kathryn; Crilly, Anne; Kurowska-Stolarska, Mariola; Plevin, Robin; van 't Hof, Rob J; Rowan, Andrew D; McInnes, Iain B; Goodyear, Carl S; Lockhart, John C; Ferrell, William R

    2016-11-01

    Proteinase-activated receptor 2 (PAR2) deficiency protects against cartilage degradation in experimental osteoarthritis (OA). The wider impact of this pathway upon OA-associated pathologies such as osteophyte formation and pain is unknown. Herein, we investigated early temporal bone and cartilage changes in experimental OA in order to further elucidate the role of PAR2 in OA pathogenesis. OA was induced in wild-type (WT) and PAR2-deficient (PAR2 -/- ) mice by destabilisation of the medial meniscus (DMM). Inflammation, cartilage degradation and bone changes were monitored using histology and microCT. In gene rescue experiments, PAR2 -/- mice were intra-articularly injected with human PAR2 (hPAR2)-expressing adenovirus. Dynamic weight bearing was used as a surrogate of OA-related pain. Osteophytes formed within 7 days post-DMM in WT mice but osteosclerosis was only evident from 14 days post induction. Importantly, PAR2 was expressed in the proliferative/hypertrophic chondrocytes present within osteophytes. In PAR2 -/- mice, osteophytes developed significantly less frequently but, when present, were smaller and of greater density; no osteosclerosis was observed in these mice up to day 28. The pattern of weight bearing was altered in PAR2 -/- mice, suggesting reduced pain perception. The expression of hPAR2 in PAR2 -/- mice recapitulated osteophyte formation and cartilage damage similar to that observed in WT mice. However, osteosclerosis was absent, consistent with lack of hPAR2 expression in subchondral bone. This study clearly demonstrates PAR2 plays a critical role, via chondrocytes, in osteophyte development and subchondral bone changes, which occur prior to PAR2-mediated cartilage damage. The latter likely occurs independently of OA-related bone changes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  15. Proteinase-activated receptor 2 modulates OA-related pain, cartilage and bone pathology

    Science.gov (United States)

    Huesa, Carmen; Ortiz, Ana C; Dunning, Lynette; McGavin, Laura; Bennett, Louise; McIntosh, Kathryn; Crilly, Anne; Kurowska-Stolarska, Mariola; Plevin, Robin; van ‘t Hof, Rob J; Rowan, Andrew D; McInnes, Iain B; Goodyear, Carl S; Lockhart, John C; Ferrell, William R

    2016-01-01

    Objective Proteinase-activated receptor 2 (PAR2) deficiency protects against cartilage degradation in experimental osteoarthritis (OA). The wider impact of this pathway upon OA-associated pathologies such as osteophyte formation and pain is unknown. Herein, we investigated early temporal bone and cartilage changes in experimental OA in order to further elucidate the role of PAR2 in OA pathogenesis. Methods OA was induced in wild-type (WT) and PAR2-deficient (PAR2−/−) mice by destabilisation of the medial meniscus (DMM). Inflammation, cartilage degradation and bone changes were monitored using histology and microCT. In gene rescue experiments, PAR2−/− mice were intra-articularly injected with human PAR2 (hPAR2)-expressing adenovirus. Dynamic weight bearing was used as a surrogate of OA-related pain. Results Osteophytes formed within 7 days post-DMM in WT mice but osteosclerosis was only evident from 14 days post induction. Importantly, PAR2 was expressed in the proliferative/hypertrophic chondrocytes present within osteophytes. In PAR2−/− mice, osteophytes developed significantly less frequently but, when present, were smaller and of greater density; no osteosclerosis was observed in these mice up to day 28. The pattern of weight bearing was altered in PAR2−/− mice, suggesting reduced pain perception. The expression of hPAR2 in PAR2−/− mice recapitulated osteophyte formation and cartilage damage similar to that observed in WT mice. However, osteosclerosis was absent, consistent with lack of hPAR2 expression in subchondral bone. Conclusions This study clearly demonstrates PAR2 plays a critical role, via chondrocytes, in osteophyte development and subchondral bone changes, which occur prior to PAR2-mediated cartilage damage. The latter likely occurs independently of OA-related bone changes. PMID:26698846

  16. Denudation and uplift of the Mawson Escarpment (eastern Lambert Graben, Antarctica) as indicated by apatite fission track data and geomorphological observation

    Science.gov (United States)

    Lisker, F.; Gibson, H.; Wilson, C.J.; Läufer, A.

    2007-01-01

    Analysis of three vertical profiles from the southern Mawson Escarpment (Lambert Graben) reveals apatite fission track (AFT) ages ranging from 102±20 to 287±23 Ma and mean lengths of 12.2 to 13.0 μm. Quantitative thermal histories derived from these data consistently indicate onset of slow cooling below 110°C began sometime prior to 300 Ma, and a second stage of rapid cooling from paleotemperatures up to ≤100°C to surface temperatures occurred in the Late Cretaceous – Paleocene. The first cooling phase refers to Carboniferous – Jurassic basement denudation up to 5 km associated with the initial rifting of the Lambert Graben. The presence of the ancient East Antarctic Erosion Surface and rapid Late Cretaceous – Paleocene cooling indicate a second denudational episode during which up to 4.5 km of sedimentary cover rocks were removed, and that is likely linked to the Cretaceous Gondwana breakup between Antarctica and India and subsequent passive continental margin formation.

  17. The effects of climate and landscape position on chemical denudation and mineral transformation in the Santa Catalina mountain critical zone observatory

    Energy Technology Data Exchange (ETDEWEB)

    Lybrand, Rebecca, E-mail: rlybrand@email.arizona.edu [Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 (United States); Rasmussen, Craig [Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 (United States); Jardine, Angie; Troch, Peter [Department of Hydrology and Water Resources, University of Arizona, Tucson, AZ 85721 (United States); Chorover, Jon [Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 (United States)

    2011-06-15

    Highlights: > Depth to paralithic contact generally increased with elevation. > Q/P ratios were higher in divergent landscape positions compared to adjacent convergent hollows. > Clay mineral assemblages changed as a function of elevation. > Climate, landscape position and erosion interactively control soil and regolith development. - Abstract: Understanding the interactions of climate, physical erosion, chemical weathering and pedogenic processes is essential when considering the evolution of critical zone systems. Interactions among these components are particularly important to predicting how semiarid landscapes will respond to forecasted changes in precipitation and temperature under future climate change. The primary goal of this study was to understand how climate and landscape structure interact to control chemical denudation and mineral transformation across a range of semiarid ecosystems in southern Arizona. The research was conducted along the steep environmental gradient encompassed by the Santa Catalina Mountains Critical Zone Observatory (SCM-CZO). The gradient is dominated by granitic parent materials and spans significant range in both mean annual temperature (>10 deg. C) and precipitation (>50 cm a{sup -1}), with concomitant shift in vegetation communities from desert scrub to mixed conifer forest. Regolith profiles were sampled from divergent and convergent landscape positions in five different ecosystems to quantify how climate-landscape position interactions control regolith development. Regolith development was quantified as depth to paralithic contact and degree of chemical weathering and mineral transformation using a combination of quantitative and semi-quantitative X-ray diffraction (XRD) analyses of bulk soils and specific particle size classes. Depth to paralithic contact was found to increase systematically with elevation for divergent positions at approximately 28 cm per 1000 m elevation, but varied inconsistently for convergent

  18. The effects of climate and landscape position on chemical denudation and mineral transformation in the Santa Catalina mountain critical zone observatory

    International Nuclear Information System (INIS)

    Lybrand, Rebecca; Rasmussen, Craig; Jardine, Angie; Troch, Peter; Chorover, Jon

    2011-01-01

    Highlights: → Depth to paralithic contact generally increased with elevation. → Q/P ratios were higher in divergent landscape positions compared to adjacent convergent hollows. → Clay mineral assemblages changed as a function of elevation. → Climate, landscape position and erosion interactively control soil and regolith development. - Abstract: Understanding the interactions of climate, physical erosion, chemical weathering and pedogenic processes is essential when considering the evolution of critical zone systems. Interactions among these components are particularly important to predicting how semiarid landscapes will respond to forecasted changes in precipitation and temperature under future climate change. The primary goal of this study was to understand how climate and landscape structure interact to control chemical denudation and mineral transformation across a range of semiarid ecosystems in southern Arizona. The research was conducted along the steep environmental gradient encompassed by the Santa Catalina Mountains Critical Zone Observatory (SCM-CZO). The gradient is dominated by granitic parent materials and spans significant range in both mean annual temperature (>10 deg. C) and precipitation (>50 cm a -1 ), with concomitant shift in vegetation communities from desert scrub to mixed conifer forest. Regolith profiles were sampled from divergent and convergent landscape positions in five different ecosystems to quantify how climate-landscape position interactions control regolith development. Regolith development was quantified as depth to paralithic contact and degree of chemical weathering and mineral transformation using a combination of quantitative and semi-quantitative X-ray diffraction (XRD) analyses of bulk soils and specific particle size classes. Depth to paralithic contact was found to increase systematically with elevation for divergent positions at approximately 28 cm per 1000 m elevation, but varied inconsistently for convergent

  19. Significance of bone marrow edema in pathogenesis of rheumatoid arthritis

    International Nuclear Information System (INIS)

    Sudoł-Szopińska, Iwona; Kontny, Ewa; Maśliński, Włodzimierz; Prochorec-Sobieszek, Monika; Warczyńska, Agnieszka; Kwiatkowska, Brygida

    2013-01-01

    Assessing the pathology of the synovium, its thickening and increased vascularity through ultrasound and magnetic resonance examinations (more often an ultrasound study alone) is still considered a sensitive parameter in the diagnosis of rheumatoid arthritis and in monitoring of treatment efficacy. Magnetic resonance studies showed that, aside from the joint pannus, the subchondral bone tissue constitutes an essential element in the development of rheumatoid arthritis. Bone marrow edema correlates with inflammation severity, joint destruction, clinical signs and symptoms of rheumatoid arthritis, and thus is considered a predictor of rapid radiological progression of the disease. The newest studies reveal that bone marrow edema may be a more sensitive indicator of the response to therapy than appearance of the synovium. Bone marrow edema presents with increased signal in T2-weighted images, being most visible in fat saturation or IR sequences (STIR, TIRM). On the other hand, it is hypointense and less evident in T1-weighted images. It becomes enhanced (hyperintense) after contrast administration. Histopathological studies confirmed that it is a result of bone inflammation (osteitis/osteomyelitis), i.e. replacememt of bone marrow fat by inflammatory infiltrates containing macrophages, T lymphocytes, B lymphocytes, plasma cells and osteoclasts. Bone marrow edema appears after a few weeks from occurrence of symptoms and therefore is considered an early marker of inflammation. It correlates with clinical assessment of disease activity and elevated markers of acute inflammatory phase, i.e. ESR and CRP. It is a reversible phenomenon and may become attenuated due to biological treatment. It is considered a “herald” of erosions, as the risk of their formation is 6-fold higher in sites where BME was previously noted

  20. Mirror denudation pattern on both sides of the Central Atlantic - a trace of the Pangea break-up?

    Science.gov (United States)

    Ruiz, G.; Saddiqi, O.; Sebti, S.; Negro, F.; Stuart, F.; Foeken, J.; Frizon de Lamotte, D.; Kramers, J.

    2009-04-01

    -Atlas. Second, they are being affected "now" but no level with such record is yet exposed. Thermal modelling was performed to decipher between the 2 scenarios using our new thermochronological and available geological constraints. Models suggest that the first scenario is most likely with a clear Triassic to Late Jurassic phase of heating until ~100-90°C that was followed by a phase of cooling until the Middle Cretaceous. These results suggest that the Meseta was buried by a 2-3 kilometres thick sedimentary pile until ~180 Ma and as a result that the concept of a topographic high limiting the Tethysian from the Atlantic has to be reconsidered. Further, denudation patterns from the mirror image of the Atlas system on the other side of the Atlantic ocean are almost identical (Grist and Zentilli, 2003) suggesting that the patterns we constrained for the Triassic until Middle Cretaceous in SW Morocco have to be related to the break-up of the Pangea and oceanization in the Central Atlantic from ~180 Ma.

  1. Broken bone

    Science.gov (United States)

    ... Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Broken bone URL of this page: //medlineplus.gov/ency/ ... following steps to reduce your risk of a broken bone: Wear protective ... pads. Create a safe home for young children. Place a gate at stairways ...

  2. Bone densitometry

    DEFF Research Database (Denmark)

    Ravn, Pernille; Alexandersen, P; Møllgaard, A

    1999-01-01

    The bisphosphonates have been introduced as alternatives to hormone replacement therapy (HRT) for the treatment and prevention of postmenopausal osteoporosis. The expected increasing application in at clinical practice demands cost-effective and easily handled methods to monitor the effect on bone....... The weak response at the distal forearm during antiresorptive treatment has restricted the use of bone densitometry at this region. We describe a new model for bone densitometry at the distal forearm, by which the response obtained is comparable to the response in other regions where bone densitometry...... is much more expensive and technically complicated. By computerized iteration of single X-ray absorptiometry forearm scans we defined a region with 65% trabecular bone. The region was analyzed in randomized, double-masked, placebo- controlled trials: a 2-year trial with alendronate (n = 69), a 1-year...

  3. Clinicopathological findings in horses with a bi- or tripartite navicular bone.

    Science.gov (United States)

    van der Zaag, Ellen J; Weerts, Erik A W S; van den Belt, Antoon J M; Back, Willem

    2016-04-09

    Navicular bone partition is a rare condition reported in horses, which is during the evaluation of a lameness or prepurchase examination often misinterpreted for a parasagittal fracture. In this report, the clinicopathological findings of three cases of navicular bone partition are evaluated. The possible pathomechanisms underlying the condition are hypothesised, focusing on a potential origin of foetal vascular disturbance. This study is furthermore aiming at a clearer and earlier recognition of navicular bone partition, since this condition would finally predispose for a clinical lameness with a poor prognosis. Case 1 was a 10-year-old Belgian Warmblood gelding with a Grade 3/5 chronic, recurrent left-forelimb lameness that had persisted for 4 months. Perineural palmar digital nerve block of the distal foot abolished the lameness. Radiographic examination revealed a bipartite navicular bone in the left forelimb. Unfortunately, the animal was lost to follow-up. Case 2 was a 7-year-old Quarter Horse stallion with a Grade 3/5 recurrent right forelimb lameness that had persisted for 2 years. The lameness switched to the contralateral left forelimb with a palmar digital nerve block. Radiographic examination identified a tripartite navicular bone in both forelimbs. Pathological examination additionally revealed chronic degenerative changes of the cartilage and subchondral bone with marked cystic changes. Case 3 was a 5-year-old Dutch Warmblood gelding with a Grade 3/5 recurrent left hindlimb lameness that had persisted for 6 months. Owing to the uncooperative behaviour of the horse, only a combined peroneal and tibial nerve block could be performed, which abolished the lameness. Radiographic examination revealed a bipartite navicular bone in the left hindlimb. Pathological examination showed a navicular bipartition in the left hindlimb, with microscopic changes comparable to those evident in Case 2; additionally, cartilage indentations were also found in the navicular

  4. Bone mineral density in patients with destructive arthrosis of the hip joint.

    Science.gov (United States)

    Okano, Kunihiko; Aoyagi, Kiyoshi; Enomoto, Hiroshi; Osaki, Makoto; Chiba, Ko; Yamaguchi, Kazumasa

    2014-05-01

    Recent reports have shown the existence of subchondral insufficiency fracture in rapidly destructive arthrosis of the hip joint (RDA), and the findings suggest that osteopenia is related to the pathogenesis of the rapid progression of this disease. Therefore, we measured bone mineral density (BMD) in RDA patients. We measured BMD of the lumbar spine, radius, and calcaneus using dual-energy X-ray absorptiometry in 19 patients with RDA and 75 with osteoarthritis of the hip (OA) and compared BMD at different skeletal sites between RDA and OA patients. No significant differences were observed in BMD of the lumbar spine, ultradistal radius, mid-radius, and calcaneous between the RDA and OA groups. Our data suggest that RDA is not accompanied by generalized osteoporosis. Factors other than generalized bone status, for example, BMD around the affected hip joint before destruction, need to be analyzed to elucidate the pathophysiological mechanism of RDA.

  5. Revascularization of femoral head ischemic necrosis with vascularized bone graft: A CT scan experimental study

    International Nuclear Information System (INIS)

    Gonzalez del Pino, J.; Knapp, K.; Gomez Castresana, F.; Benito, M.

    1990-01-01

    An ischemic necrosis of the femoral head was induced in 15 mongrel adult dogs using the technique described by Gartsman et al. Five weeks later, a free vascularized rib graft was transferred into the previously induced ischemic femoral head. High resolution computed tomographic scanning was used to evaluate revascularization 4, 8 and 12 weeks after grafting. The femoral head exhibited new vessel formation throughout the study. Arterial terminal branches arising from the rib graft medullary and periosteal circulations extended beyond the rib graft, entered the head, and reached the subchondral plate. Even where the rib graft did not replenish the central core of the head, there was vascular supply from the grafted bone's vascular tree. These results suggest that a free vascularized bone graft is able to revascularize an experimentally induced ischemic femoral head necrosis. (orig.)

  6. Subchondral Insufficiency Fracture of the Femoral Head in a Pregnant Woman with Pre-existing Anorexia Nervosa.

    Science.gov (United States)

    Kasahara, Kyoko; Mimura, Tomohiro; Moritani, Suzuko; Kawasaki, Taku; Imai, Shinji; Tsuji, Shunichiro; Kimura, Fuminori; Murakami, Takashi

    2018-05-01

    Subchondral insufficiency fracture (SIF) is a fragility fracture secondary to osteoporosis that leads to collapse of the femoral head with no evidence of osteonecrosis. SIF of the femoral head has been reported in adults of varying ages and both sexes, but it has never been reported to occur in pregnant women. Herein, we describe a 40-year-old primiparous patient with pre-existing anorexia nervosa who developed SIF of the femoral head in the third trimester. At 29 weeks of gestation, the patient complained of sudden pain on walking in both hips. Despite the bed rest, her hip pain increased; consequently, cesarean section was performed at 36 weeks. After delivery, plain radiographs showed that the left femoral head was collapsed. Dual-energy X-ray absorptiometry indicated that the patient was osteoporotic. The magnetic resonance imaging (MRI) of her hips showed the findings that were compatible with SIF. Her left hip pain worsened during follow-up, and a radiograph showed progressive collapse of the left femoral head. The patient then underwent left bipolar hip arthroplasty 18 months after delivery, and she was diagnosed with SIF histopathologically. This is the first report of SIF in a pregnant woman that may reflect pregnancy-associated osteoporosis. SIF in pregnancy might be overlooked or misdiagnosed because the MRI findings have several overlaps with those of other hip disorders. Precise diagnosis of SIF in pregnancy may contribute to a better outcome by avoiding early arthroplasty in young women and appropriate evaluation of the osteopenic status of the patient.

  7. Bone healing and bone substitutes.

    Science.gov (United States)

    Costantino, Peter D; Hiltzik, David; Govindaraj, Satish; Moche, Jason

    2002-02-01

    With the advent of new biomaterials and surgical techniques, the reconstructive surgeon has a wider range of treatment modalities for the rehabilitation and reconstruction of craniofacial skeletal deformities than ever before. These innovative substances act as true bone graft substitutes, thereby allowing the surgeon to avoid the use of autogenous bone grafts and their associated donor site morbidity. Surgeons have long been interested in producing a composite graft that can heal faster by induction, incorporate with surrounding tissues, and be remodeled to resemble native bone. Currently, there are a host of bone graft substitutes available that vary in both their composition and properties. Craniomaxillofacial surgeons must therefore become comfortable with numerous biomaterials to best tailor the treatment for each patient individually. Ongoing investigations into the next phase of tissue engineering will continue to bring us closer to the ability to regenerate or replace bone.

  8. Climate-driven unsteady denudation and sediment flux in a high-relief unglaciated catchment-fan using 26Al and 10Be: Panamint Valley, California

    Science.gov (United States)

    Mason, Cody C.; Romans, Brian W.

    2018-06-01

    Environmental changes within erosional catchments of sediment routing systems are predicted to modulate sediment transfer dynamics. However, empirical and numerical models that predict such phenomena are difficult to test in natural systems over multi-millennial timescales. Tectonic boundary conditions and climate history in the Panamint Range, California, are relatively well-constrained by existing low-temperature thermochronology and regional multi-proxy paleoclimate studies, respectively. Catchment-fan systems present there minimize sediment storage and recycling, offering an excellent natural laboratory to test models of climate-sedimentary dynamics. We used stratigraphic characterization and cosmogenic radionuclides (CRNs; 26Al and 10Be) in the Pleasant Canyon complex (PCC), a linked catchment-fan system, to examine the effects of Pleistocene high-magnitude, high-frequency climate change on CRN-derived denudation rates and sediment flux in a high-relief, unglaciated catchment-fan system. Calculated 26Al/10Be burial ages from 13 samples collected in an ∼180 m thick outcropping stratigraphic succession range from ca. 1.55 ± 0.22 Ma in basal strata, to ca. 0.36 ± 0.18-0.52 ± 0.20 Ma within the uppermost part of the succession. The mean long-term CRN-derived paleodenudation rate, 36 ± 8 mm/kyr (1σ), is higher than the modern rate of 24 ± 0.6 mm/kyr from Pleasant Canyon, and paleodenudation rates during the middle Pleistocene display some high-frequency variability in the high end (up to 54 ± 10 mm/kyr). The highest CRN-derived denudation rates are associated with stratigraphic evidence for increased precipitation during glacial-pluvial events after the middle Pleistocene transition (post ca. 0.75 Ma), suggesting 100 kyr Milankovitch periodicity could drive the observed variability. We investigated the potential for non-equilibrium sedimentary processes, i.e. increased landslides or sediment storage/recycling, to influence apparent paleodenudation rates

  9. Dilution of 10Be in detrital quartz by earthquake-induced landslides: Implications for determining denudation rates and potential to provide insights into landslide sediment dynamics

    Science.gov (United States)

    West, A. Joshua; Hetzel, Ralf; Li, Gen; Jin, Zhangdong; Zhang, Fei; Hilton, Robert G.; Densmore, Alexander L.

    2014-06-01

    The concentration of 10Be in detrital quartz (10Beqtz) from river sediments is now widely used to quantify catchment-wide denudation rates but may also be sensitive to inputs from bedrock landslides that deliver sediment with low 10Beqtz. Major landslide-triggering events can provide large amounts of low-concentration material to rivers in mountain catchments, but changes in river sediment 10Beqtz due to such events have not yet been measured directly. Here we examine the impact of widespread landslides triggered by the 2008 Wenchuan earthquake on 10Beqtz in sediment samples from the Min Jiang river basin, in Sichuan, China. Landslide deposit material associated with the Wenchuan earthquake has consistently lower 10Beqtz than in river sediment prior to the earthquake. River sediment 10Beqtz decreased significantly following the earthquake downstream of areas of high coseismic landslide occurrence (i.e., with greater than ∼0.3% of the upstream catchment area affected by landslides), because of input of the 10Be-depleted landslide material, but showed no systematic changes where landslide occurrence was low. Changes in river sediment 10Beqtz concentration were largest in small first-order catchments but were still significant in large river basins with areas of 104-105 km. Spatial and temporal variability in river sediment 10Beqtz has important implications for inferring representative denudation rates in tectonically active, landslide-dominated environments, even in large basins. Although the dilution of 10Beqtz in river sediment by landslide inputs may complicate interpretation of denudation rates, it also may provide a possible opportunity to track the transport of landslide sediment. The associated uncertainties are large, but in the Wenchuan case, calculations based on 10Be mixing proportions suggest that river sediment fluxes in the 2-3 years following the earthquake increased by a similar order of magnitude in the 0.25-1 mm and the mixing calculations and

  10. Denudational slope processes on weathered basalt in northern California: 130 ka history of soil development, periods of slope stability and colluviation, and climate change

    Science.gov (United States)

    McDonald, Eric; Harrison, Bruce; Baldwin, John; Page, William; Rood, Dylan

    2017-04-01

    The geomorphic history of hillslope evolution is controlled by multiple types of denudational processes. Detailed analysis of hillslope soil-stratigraphy provides a means to identify the timing of periods of slope stability and non-stability, evidence of the types of denudational processes, and possible links to climatic drivers. Moreover, the degree of soil formation and the presence of buried or truncated soils provide evidence of the relative age of alternating periods of colluviation and stability. We use evaluation of soil stratigraphy, for a small forested hillslope (soils and slope colluvium are derived from highly weathered basalt. Stratigraphic interpretation is reinforced with soil profile development index (PDI) derived age estimates, tephrochronology, luminescence ages on colluvium, and He3 nuclide exposure dates. Soils formed along hilltop ridges are well developed and reflect deep (>2-3 m) in-situ weathering of the basalt bedrock. PDI age estimates and He3 exposure dates indicate that these hilltop soils had been in place for 100-130 ka, implying a long period of relative surface stability. At about 40-30 ka, soil stratigraphy indicates the onset of 3 distinct cycles of denudation of the hilltop and slopes. Evidence for changes in stability and onset of soil erosion is the presence of several buried soils formed in colluvium downslope of the hilltop. These buried soils have formed in sediment derived from erosion of the hilltop soils (i.e. soil parent material of previously weathered soil matrix and basalt cobbles). The oldest buried soil indicates that slope stability was re-established between 32-23 ka, with stability and soil formation lasting to about 10 ka. Soil-stratigraphy indicates that two additional intervals of downslope transport of sediment between 6-10 ka, and 2-5 ka. Soil properties indicate that the primary method of downslope transport is largely due to tree throw and faunal burrowing. Onset of slope instability at 40-30 ka appears to

  11. Bone Biopsy

    Science.gov (United States)

    ... several inches long with a hollow core to capture the bone specimen. The CT scanner is typically ... IV), ultrasound machine and devices that monitor your heart beat and blood pressure. top of page How ...

  12. Bone pain

    DEFF Research Database (Denmark)

    Frost, Charlotte Ørsted; Hansen, Rikke Rie; Heegaard, Anne-Marie

    2016-01-01

    Skeletal conditions are common causes of chronic pain and there is an unmet medical need for improved treatment options. Bone pain is currently managed with disease modifying agents and/or analgesics depending on the condition. Disease modifying agents affect the underlying pathophysiology...... of the disease and reduce as a secondary effect bone pain. Antiresorptive and anabolic agents, such as bisphosphonates and intermittent parathyroid hormone (1-34), respectively, have proven effective as pain relieving agents. Cathepsin K inhibitors and anti-sclerostin antibodies hold, due to their disease...... modifying effects, promise of a pain relieving effect. NSAIDs and opioids are widely employed in the treatment of bone pain. However, recent preclinical findings demonstrating a unique neuronal innervation of bone tissue and sprouting of sensory nerve fibers open for new treatment possibilities....

  13. Bone sarcomas

    International Nuclear Information System (INIS)

    Mudry, P.

    2008-01-01

    Bone sarcomas are malignancies with peak incidence in adolescents and young adults. The most frequent are osteosarcoma and Ewing sarcoma/PNET, in an older adults are seen chondrosarcomas, other ones are rare. In general, biology of sarcomas is closely related to pediatric malignancies with fast growth, local aggressiveness, tendency to early hematogenic dissemination and chemo sensitivity. Diagnostics and treatment of bone sarcomas should be done in well experienced centres due to low incidence and broad issue of this topic. An interdisciplinary approach and staff education is essential in due care of patients with bone sarcoma. If these criteria are achieved, the cure rate is contemporary at 65 - 70 %, while some subpopulation of patients has chance for cure up to 90 %. Osteosarcoma and Ewing sarcoma/PNET are discussed below as types of most frequent bone sarcoma. (author)

  14. Compositional studies at the Bone-Cartilage interface using PIXE, RBS and cSAXS techniques

    International Nuclear Information System (INIS)

    Kaabar, W.; Gundogdu, O.; Bradley, D.A.; Bunk, O.; Pfeiffer, F.; Pfeiffer, F.; Farquharson, M.J.; Webb, M.; Jeynes, C.

    2009-01-01

    Micro Proton Induced X-ray Emission (μ-PIXE) analysis has been employed herein in investigating and quantifying the distribution of a number of essential cations in two thin slices of normal and diseased human articular cartilage, the latter being affected by osteoarthritis (OA). The elemental distribution maps for Ca, P, K, S and Zn in the normal and diseased slices showed similar patterns with marked increases in elemental concentrations in the bone-cartilage interface. The S concentration was significantly lower in bone than in cartilage. Conversely, the Ca and P concentrations were higher in bone. The Ca/P ratio (2.22) of the diseased slice was determined by employing the Rutherford backscattering technique (RBS). The RBS figures of this investigation agree with values previously reported by others. Structural and organisational changes of collagen networks were investigated by coherent Small-Angle X-ray Scattering (SAXS) using beamline facilities at the Swiss Light Source (SLS) for a decalcified diseased human articular cartilage slice. The SAXS findings showed a gradual reorientation of collagen type II fibres of cartilage from parallel to the surface of the joint to normal to the bone-cartilage interface. Similar patterns of orientation were observed at the subchondral bone to bone-cartilage interface

  15. Development and application of compact denuder sampling techniques with in situ derivatization followed by gas chromatography-mass spectrometry for halogen speciation in volcanic plumes

    Science.gov (United States)

    Rüdiger, Julian; Bobrowski, Nicole; Hoffmann, Thorsten

    2015-04-01

    Volcanoes are a large source for several reactive atmospheric trace gases including sulphur and halogen containing species. The detailed knowledge of volcanic plume chemistry can give insights into subsurface processes and can be considered as a useful geochemical tool for monitoring of volcanic activity, especially halogen to sulphur ratios (e.g. Bobrowski and Giuffrida, 2012; Donovan et al., 2014). The reactive bromine species bromine monoxide (BrO) is of particular interest, because BrO as well as SO2 are readily measurable by UV spectrometers at a safe distance. Furthermore it is formed in the plume by a multiphase reaction mechanism under depletion of ozone in the plume. The abundance of BrO changes as a function of the reaction time and therefore distance from the vent as well as the spatial position in the plume. Due to the lack of analytical approaches for the accurate speciation of certain halogens (HBr, Br2, Br, BrCl, HOBr etc.) there are still uncertainties about the magnitude of volcanic halogen emissions and in particular their specificationtheir species and therefore also in the understanding of the bromine chemistry in volcanic plumes (Bobrowski et al., 2007). In this study, the first application of a 1,3,5-trimethoxybenzene (1,3,5-TMB)-coated gas diffusion denuder (Huang and Hoffmann, 2008) on volcanic gases proved to be suitable to collect selectively gaseous bromine species with oxidation states of +1 or 0 (Br2 and BrO(H)), while being ignorant to HBr (OS -1). The reaction of 1,3,5-TMB with bromine gives 1-bromo-2,4,6-trimethoxybenzene (1-bromo-2,4,6-TMB) - other halogens give corresponding products. The diffusion denuder technique allows sampling of gaseous compounds exclusively without collecting particulate matter. Choosing a flow rate of 500 mL-min-1 and a denuder length of 0.5 m a nearly quantitative collection efficiency was achieved. Solvent elution of the derivatized analytes and subsequent analysis with gas chromatography

  16. Geomorphology, denudation rates, and stream channel profiles reveal patterns of mountain building adjacent to the San Andreas fault in northern California, USA

    Science.gov (United States)

    DeLong, Stephen B.; Hilley, George E.; Prentice, Carol S.; Crosby, Christopher J.; Yokelson, Intan N.

    2017-01-01

    Relative horizontal motion along strike-slip faults can build mountains when motion is oblique to the trend of the strike-slip boundary. The resulting contraction and uplift pose off-fault seismic hazards, which are often difficult to detect because of the poor vertical resolution of satellite geodesy and difficulty of locating offset datable landforms in active mountain ranges. Sparse geomorphic markers, topographic analyses, and measurement of denudation allow us to map spatiotemporal patterns of uplift along the northern San Andreas fault. Between Jenner and Mendocino, California, emergent marine terraces found southwest of the San Andreas fault record late Pleistocene uplift rates between 0.20 and 0.45 mm yr–1 along much of the coast. However, on the northeast side of the San Andreas fault, a zone of rapid uplift (0.6–1.0 mm yr–1) exists adjacent to the San Andreas fault, but rates decay northeastward as the coast becomes more distant from the San Andreas fault. A newly dated 4.5 Ma shallow-marine deposit located at ∼500 m above sea level (masl) adjacent to the San Andreas fault is warped down to just 150 masl 15 km northeast of the San Andreas fault, and it is exposed at just 60–110 masl to the west of the fault. Landscape denudation rates calculated from abundance of cosmogenic radionuclides in fluvial sediment northeast of, and adjacent to, the San Andreas fault are 0.16–0.29 mm yr–1, but they are only 0.03–0.07 mm yr–1 west of the fault. Basin-average channel steepness and the denudation rates can be used to infer the erosive properties of the underlying bedrock. Calibrated erosion rates can then be estimated across the entire landscape using the spatial distribution of channel steepness with these erosive properties. The lower-elevation areas of this landscape that show high channel steepness (and hence calibrated erosion rate) are distinct from higher-elevation areas with systematically lower channel steepness and denudation rates

  17. A wet effluent denuder/mist-chamber coupled to ion chromatography for the continuous measurement of atmospheric HONO, HNO{sub 3}, NO{sub 3}{sup -} and SO{sub 4}{sup 2-}.

    Energy Technology Data Exchange (ETDEWEB)

    Zellweger, C.; Baltensperger, U. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Hofer, P. [EMPA, Duebendorf (Switzerland)

    1997-09-01

    A denuder/mist chamber system has been developed for the continuous automated measurement of low level concentrations of HONO, HNO{sub 3} as well as of NO{sub 3}{sup -} and SO{sub 4}{sup 2-}. (author) 2 figs., 1 ref.

  18. Hunner-Type (Classic Interstitial Cystitis: A Distinct Inflammatory Disorder Characterized by Pancystitis, with Frequent Expansion of Clonal B-Cells and Epithelial Denudation.

    Directory of Open Access Journals (Sweden)

    Daichi Maeda

    Full Text Available Interstitial cystitis (IC is a chronic bladder disease with urinary frequency, bladder discomfort or bladder pain of unknown etiology. Based on cystoscopic findings, patients with IC are classified as either Hunner-type/classic IC (HIC, presenting with a specific Hunner lesion, or non-Hunner-type IC (NHIC, presenting with no Hunner lesion, but post-hydrodistension mucosal bleeding. Inflammatory cell infiltration, composed predominantly of lymphocytes, plasma cells and epithelial denudation, has in the past been documented as a major pathological IC finding. However, the significance of the pathological evaluation of IC, especially with regard to the difference between HIC and NHIC, has been downplayed in recent years. In this study, we performed immunohistochemical quantification of infiltrating T-lymphocytes, B-lymphocytes and plasma cells, and measured the amount of residual epithelium in urinary bladder biopsy specimens taken from patients with HIC and NHIC, and those with no IC, using image analysis software. In addition, in situ hybridization of the light chains was performed to examine clonal B-cell expansion. Lymphoplasmacytic infiltration was significantly more severe in HIC specimens than in NHIC specimens (P <0.0001. Substantial lymphoplasmacytic inflammation (≥200 cells/mm2 was observed in 93% of HIC specimens, whereas only 8% of NHIC specimens were inflamed. Plasmacytic infiltration was more prominent in HIC specimens compared with NHIC and non-IC cystitis specimens (P <0.005. Furthermore, expansion of light-chain-restricted B-cells was observed in 31% of cases of HIC. The amount of residual epithelium was decreased in HIC specimens compared with NHIC specimens and non-IC cystitis specimens (P <0.0001. These results suggest that NHIC and HIC are distinct pathological entities, with the latter characterized by pancystitis, frequent clonal B-cell expansion and epithelial denudation. An abnormality in the B-cell population may be

  19. Bone--bone marrow interactions

    International Nuclear Information System (INIS)

    Patt, H.M.

    1976-01-01

    Within medullary cavities, blood formation tends to be concentrated near bone surfaces and this raises interesting questions about hematopoietic consequences of radionuclide fixation in osseous tissue. Thus, it may be important, on the one hand, to consider the medullary radiation dose distribution as well as total marrow dose from bone-bound radioelements and, on the other, to inquire about possible hematopoietic implications of radiation damage to endosteal surfaces per se. The reasons for this are discussed

  20. Bone mineral content and bone metabolism in young adults with severe periodontitis

    DEFF Research Database (Denmark)

    Wowern von, N.; Westergaard, J.; Kollerup, G.

    2001-01-01

    Bone loss, bone markers, bone metabolism, bone mineral content, osteoporosis, severe periodontitis......Bone loss, bone markers, bone metabolism, bone mineral content, osteoporosis, severe periodontitis...

  1. [On the preparation and mechanical properties of PVA hydrogel bionic cartilage/bone composite artificial articular implants].

    Science.gov (United States)

    Meng, Haoye; Zheng, Yudong; Huang, Xiaoshan; Yue, Bingqing; Xu, Hong; Wang, Yingjun; Chen, Xiaofeng

    2010-10-01

    In view of the problems that conventional artificial cartilages have no bioactivity and are prone to peel off in repeated uses as a result of insufficient strength to bond with subchondral bone, we have designed and prepared a novel kind of PVA-BG composite hydrogel as bionic artificial articular cartilage/bone composite implants. The effects of processes and conditions of preparation on the mechanical properties of implant were explored. In addition, the relationships between compression strain rate, BG content, PVA hydrogels thickness and compressive tangent modulus were also explicated. We also analyzed the effects of cancellous bone aperture, BG and PVA content on the shear strength of bonding interface of artificial articular cartilage with cancellous bone. Meanwhile, the bonding interface of artificial articular cartilage and cancellous bone was characterized by scanning electron microscopy. It was revealed that the compressive modulus of composite implants was correspondingly increased with the adding of BG content and the augments of PVA hydrogel thickness. The compressive modulus and bonding interface were both related to the apertures of cancellous bone. The compressive modulus of composite implants was 1.6-2.23 MPa and the shear strength of bonding interface was 0.63-1.21 MPa. These results demonstrated that the connection between artificial articular cartilage and cancellous bone was adequately firm.

  2. From bone biology to bone analysis.

    NARCIS (Netherlands)

    Schoenau, E.; Saggese, G.; Peter, F.; Baroncelli, G.I.; Shaw, N.J.; Crabtree, N.J.; Zadik, Z.; Neu, C.M.; Noordam, C.; Radetti, G.; Hochberg, Z.

    2004-01-01

    Bone development is one of the key processes characterizing childhood and adolescence. Understanding this process is not only important for physicians treating pediatric bone disorders, but also for clinicians and researchers dealing with postmenopausal and senile osteoporosis. Bone densitometry has

  3. Bone lesion biopsy

    Science.gov (United States)

    Bone biopsy; Biopsy - bone ... the cut, then pushed and twisted into the bone. Once the sample is obtained, the needle is ... sample is sent to a lab for examination. Bone biopsy may also be done under general anesthesia ...

  4. Facts about Broken Bones

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Broken Bones KidsHealth / For Kids / Broken Bones What's in this ... sticking through the skin . What Happens When a Bone Breaks? It hurts to break a bone! It's ...

  5. Broken Bones (For Parents)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Broken Bones KidsHealth / For Parents / Broken Bones What's in this ... bone fragments in place. When Will a Broken Bone Heal? Fractures heal at different rates, depending upon ...

  6. Quantitative 3D analysis of bone in hip osteoarthritis using clinical computed tomography

    International Nuclear Information System (INIS)

    Turmezei, Tom D.; Treece, Graham M.; Gee, Andrew H.; Fotiadou, Anastasia F.; Poole, Kenneth E.S.

    2016-01-01

    To assess the relationship between proximal femoral cortical bone thickness and radiological hip osteoarthritis using quantitative 3D analysis of clinical computed tomography (CT) data. Image analysis was performed on clinical CT imaging data from 203 female volunteers with a technique called cortical bone mapping (CBM). Colour thickness maps were created for each proximal femur. Statistical parametric mapping was performed to identify statistically significant differences in cortical bone thickness that corresponded with the severity of radiological hip osteoarthritis. Kellgren and Lawrence (K and L) grade, minimum joint space width (JSW) and a novel CT-based osteophyte score were also blindly assessed from the CT data. For each increase in K and L grade, cortical thickness increased by up to 25 % in distinct areas of the superolateral femoral head-neck junction and superior subchondral bone plate. For increasing severity of CT osteophytes, the increase in cortical thickness was more circumferential, involving a wider portion of the head-neck junction, with up to a 7 % increase in cortical thickness per increment in score. Results were not significant for minimum JSW. These findings indicate that quantitative 3D analysis of the proximal femur can identify changes in cortical bone thickness relevant to structural hip osteoarthritis. (orig.)

  7. X-ray phase contrast imaging of the bone-cartilage interface

    International Nuclear Information System (INIS)

    Ismail, Elna Che; Kaabar, W.; Garrity, D.; Gundogdu, O.; Bunk, O.; Pfeiffer, F.; Farquharson, M.J.; Bradley, D.A.

    2010-01-01

    Synovial joints articulate in a lubricating environment, the system providing for smooth articulation. The articular cartilage overlying the bone consists of a network of collagen fibres. This network is essential to cartilage integrity, suffering damage in degenerative joint disease such as osteoarthritis. At Surrey and also in work conducted by this group at the Paul Scherrer Institute (PSI) synchrotron site we have been applying a number of techniques to study the bone-cartilage interface and of changes occurring in this with disease. One of the techniques attracting particular interest is X-ray phase contrast imaging, yielding information on anatomical features that manifest from the large scale organisation of collagen and the mineralised phase contained within the collagen fibres in the deep cartilage zone. This work briefly reviews some of the basic supporting physics of X-ray phase contrast imaging and then shows example images of the articular surface and subchondral bone and other supporting results obtained to-date. Present results have been obtained on sections of bone not displaying evidence of an osteoarthritic lesion and can be used as a baseline against which diseased bone can be compared.

  8. X-ray phase contrast imaging of the bone-cartilage interface

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, Elna Che; Kaabar, W.; Garrity, D.; Gundogdu, O. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Bunk, O. [Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Pfeiffer, F. [Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); Farquharson, M.J. [Department of Radiography, City University, London EC1V OHB (United Kingdom); Bradley, D.A. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom)], E-mail: d.a.bradley@surrey.ac.uk

    2010-04-15

    Synovial joints articulate in a lubricating environment, the system providing for smooth articulation. The articular cartilage overlying the bone consists of a network of collagen fibres. This network is essential to cartilage integrity, suffering damage in degenerative joint disease such as osteoarthritis. At Surrey and also in work conducted by this group at the Paul Scherrer Institute (PSI) synchrotron site we have been applying a number of techniques to study the bone-cartilage interface and of changes occurring in this with disease. One of the techniques attracting particular interest is X-ray phase contrast imaging, yielding information on anatomical features that manifest from the large scale organisation of collagen and the mineralised phase contained within the collagen fibres in the deep cartilage zone. This work briefly reviews some of the basic supporting physics of X-ray phase contrast imaging and then shows example images of the articular surface and subchondral bone and other supporting results obtained to-date. Present results have been obtained on sections of bone not displaying evidence of an osteoarthritic lesion and can be used as a baseline against which diseased bone can be compared.

  9. [Resection of a carpal bone row in a Pustertaler Sprinze cow with chronic purulent arthritis of the carpal joint and osteomyelitis].

    Science.gov (United States)

    Kofler, J; Peterbauer, C

    2014-01-01

    This case report describes the clinical and radiographic findings and the surgical treatment of a serofibrinous arthritis of the antebrachiocarpal joint and of a chronic purulent arthritis of the intercarpal and carpometacarpal joints with osteomyelitis of the distal carpal bones and subchondral osteomyelitis of the proximal metacarpal bones in a cow of the breed "Pustertaler Sprinze". The therapy comprised an arthrotomy of both joint spaces and the resection of the distal row of the carpal bones. The right forelimb had been immobilised for 70 days by a full limb cast. After this period, radiographs revealed an ob- vious ankylosis of the carpal joint, and the cow showed only a slight lameness. Six years postoperatively this cow was still in the herd and had produced six calves.

  10. Bone scans

    International Nuclear Information System (INIS)

    Hetherington, V.J.

    1989-01-01

    Oftentimes, in managing podiatric complaints, clinical and conventional radiographic techniques are insufficient in determining a patient's problem. This is especially true in the early stages of bone infection. Bone scanning or imaging can provide additional information in the diagnosis of the disorder. However, bone scans are not specific and must be correlated with clinical, radiographic, and laboratory evaluation. In other words, bone scanning does not provide the diagnosis but is an important bit of information aiding in the process of diagnosis. The more useful radionuclides in skeletal imaging are technetium phosphate complexes and gallium citrate. These compounds are administered intravenously and are detected at specific time intervals postinjection by a rectilinear scanner with minification is used and the entire skeleton can be imaged from head to toe. Minification allows visualization of the entire skeleton in a single image. A gamma camera can concentrate on an isolated area. However, it requires multiple views to complete the whole skeletal image. Recent advances have allowed computer augmentation of the data received from radionucleotide imaging. The purpose of this chapter is to present the current radionuclides clinically useful in podiatric patients

  11. Osteoclasts prefer aged bone

    DEFF Research Database (Denmark)

    Henriksen, K; Leeming, Diana Julie; Byrjalsen, I

    2007-01-01

    We investigated whether the age of the bones endogenously exerts control over the bone resorption ability of the osteoclasts, and found that osteoclasts preferentially develop and resorb bone on aged bone. These findings indicate that the bone matrix itself plays a role in targeted remodeling...... of aged bones....

  12. Bone graft revascularization strategies

    NARCIS (Netherlands)

    Willems, W.F.

    2014-01-01

    Reconstruction of avascular necrotic bone by pedicled bone grafting is a well-known treatment with little basic research supporting its application. A new canine model was used to simulate carpal bone avascular necrosis. Pedicled bone grafting proved to increase bone remodeling and bone blood flow,

  13. Bone marker gene expression in calvarial bones: different bone microenvironments.

    Science.gov (United States)

    Al-Amer, Osama

    2017-12-01

    In calvarial mice, mesenchymal stem cells (MSCs) differentiate into osteoprogenitor cells and then differentiate into osteoblasts that differentiate into osteocytes, which become embedded within the bone matrix. In this case, the cells participating in bone formation include MSCs, osteoprogenitor cells, osteoblasts and osteocytes. The calvariae of C57BL/KaLwRijHsD mice consist of the following five bones: two frontal bones, two parietal bones and one interparietal bone. This study aimed to analyse some bone marker genes and bone related genes to determine whether these calvarial bones have different bone microenvironments. C57BL/KaLwRijHsD calvariae were carefully excised from five male mice that were 4-6 weeks of age. Frontal, parietal, and interparietal bones were dissected to determine the bone microenvironment in calvariae. Haematoxylin and eosin staining was used to determine the morphology of different calvarial bones under microscopy. TaqMan was used to analyse the relative expression of Runx2, OC, OSX, RANK, RANKL, OPG, N-cadherin, E-cadherin, FGF2 and FGFR1 genes in different parts of the calvariae. Histological analysis demonstrated different bone marrow (BM) areas between the different parts of the calvariae. The data show that parietal bones have the smallest BM area compared to frontal and interparietal bones. TaqMan data show a significant increase in the expression level of Runx2, OC, OSX, RANKL, OPG, FGF2 and FGFR1 genes in the parietal bones compared with the frontal and interparietal bones of calvariae. This study provides evidence that different calvarial bones, frontal, parietal and interparietal, contain different bone microenvironments.

  14. Combined nanoindentation testing and scanning electron microscopy of bone and articular calcified cartilage in an equine fracture predilection site.

    Science.gov (United States)

    Doube, M; Firth, E C; Boyde, A; Bushby, A J

    2010-06-03

    Condylar fracture of the third metacarpal bone (Mc3) is the commonest cause of racetrack fatality in Thoroughbred horses. Linear defects involving hyaline articular cartilage, articular calcified cartilage (ACC) and subchondral bone (SCB) have been associated with the fracture initiation site, which lies in the sagittal grooves of the Mc3 condyle. We discovered areas of thickened and abnormally-mineralised ACC in the sagittal grooves of several normal 18-month-old horses, at the same site that linear defects and condylar fracture occur in older Thoroughbreds and questioned whether this tissue had altered mechanical properties. We embedded bone slices in PMMA, prepared flat surfaces normal to the articular surface and studied ACC and SCB using combined quantitative backscattered electron scanning electron microscopy (qBSE) and nanoindentation testing: this allowed correlation of mineralisation density and tissue stiffness (E) at the micron scale. We studied both normal and affected grooves, and also normal condylar regions. Large arrays of indentations could be visualised as 2-dimensional maps of E with a limit to resolution of indentation spacing, which is much larger than qBSE pixel spacing. ACC was more highly mineralised but less stiff in early linear defects than in control regions, while subchondral bone was more highly mineralised and stiffer in specimens with early linear defects than those without. Thus both ACC and SCB mineralisation may be abnormal in a class of early linear defect in 18-month-old Thoroughbred horses, and this may possibly contribute to later fracture of the Mc3 condyle.

  15. Combined nanoindentation testing and scanning electron microscopy of bone and articular calcified cartilage in an equine fracture predilection site

    Directory of Open Access Journals (Sweden)

    M Doube

    2010-06-01

    Full Text Available Condylar fracture of the third metacarpal bone (Mc3 is the commonest cause of racetrack fatality in Thoroughbred horses. Linear defects involving hyaline articular cartilage, articular calcified cartilage (ACC and subchondral bone (SCB have been associated with the fracture initiation site, which lies in the sagittal grooves of the Mc3 condyle. We discovered areas of thickened and abnormally-mineralised ACC in the sagittal grooves of several normal 18-month-old horses, at the same site that linear defects and condylar fracture occur in older Thoroughbreds and questioned whether this tissue had altered mechanical properties. We embedded bone slices in PMMA, prepared flat surfaces normal to the articular surface and studied ACC and SCB using combined quantitative backscattered electron scanning electron microscopy (qBSE and nanoindentation testing: this allowed correlation of mineralisation density and tissue stiffness (E at the micron scale. We studied both normal and affected grooves, and also normal condylar regions. Large arrays of indentations could be visualised as 2-dimensional maps of E with a limit to resolution of indentation spacing, which is much larger than qBSE pixel spacing. ACC was more highly mineralised but less stiff in early linear defects than in control regions, while subchondral bone was more highly mineralised and stiffer in specimens with early linear defects than those without. Thus both ACC and SCB mineralisation may be abnormal in a class of early linear defect in 18-month-old Thoroughbred horses, and this may possibly contribute to later fracture of the Mc3 condyle.

  16. [Frontier in bone biology].

    Science.gov (United States)

    Takeda, Shu

    2015-10-01

    Bone is an active organ in which bone mass is maintained by the balance between osteoblastic bone formation and osteoclastic bone resorption, i.e., coupling of bone formation and bone resorption. Recent advances in molecular bone biology uncovered the molecular mechanism of the coupling. A fundamental role of osteocyte in the maintenance of bone mass and whole body metabolism has also been revealed recently. Moreover, neurons and neuropeptides have been shown to be intimately involved in bone homeostasis though inter-organ network, in addition to "traditional" regulators of bone metabolism such as soluble factors and cytokines

  17. Combined Effect of Subchondral Drilling and Hyaluronic Acid with/without Diacerein in Full-Thickness Articular Cartilage Lesion in Rabbits

    Directory of Open Access Journals (Sweden)

    Wanwisa Suwannaloet

    2012-01-01

    Full Text Available The osteochondral healing potential of hyaluronic acid (HA plus diacerein was evaluated in subchondral-drilling- (SCD- induced fibrocartilage generation in rabbits. A full-thickness chondral defect was created along the patellar groove of both knees and then SCD was subsequently performed only in the left knee. A week later, the rabbits were allocated into 3 groups to receive weekly intra-articular (IA injection for 5 weeks with normal saline solution (NSS (group 1 or with HA (group 2 and group 3. Starting at the first IA injection, rabbits were also gavaged daily for 9 weeks with NSS (group 1 and group 2 or with diacerein (group 3. The animals were then sacrificed for evaluation. The newly formed tissue in SCD lesions showed significantly better histological grading scale and had higher content of type II collagen in HA-treated group compared to NSS control. In addition, adding oral diacerein to HA injection enhanced healing potential of HA.

  18. Quantitative 3D analysis of bone in hip osteoarthritis using clinical computed tomography.

    Science.gov (United States)

    Turmezei, Tom D; Treece, Graham M; Gee, Andrew H; Fotiadou, Anastasia F; Poole, Kenneth E S

    2016-07-01

    To assess the relationship between proximal femoral cortical bone thickness and radiological hip osteoarthritis using quantitative 3D analysis of clinical computed tomography (CT) data. Image analysis was performed on clinical CT imaging data from 203 female volunteers with a technique called cortical bone mapping (CBM). Colour thickness maps were created for each proximal femur. Statistical parametric mapping was performed to identify statistically significant differences in cortical bone thickness that corresponded with the severity of radiological hip osteoarthritis. Kellgren and Lawrence (K&L) grade, minimum joint space width (JSW) and a novel CT-based osteophyte score were also blindly assessed from the CT data. For each increase in K&L grade, cortical thickness increased by up to 25 % in distinct areas of the superolateral femoral head-neck junction and superior subchondral bone plate. For increasing severity of CT osteophytes, the increase in cortical thickness was more circumferential, involving a wider portion of the head-neck junction, with up to a 7 % increase in cortical thickness per increment in score. Results were not significant for minimum JSW. These findings indicate that quantitative 3D analysis of the proximal femur can identify changes in cortical bone thickness relevant to structural hip osteoarthritis. • CT is being increasingly used to assess bony involvement in osteoarthritis • CBM provides accurate and reliable quantitative analysis of cortical bone thickness • Cortical bone is thicker at the superior femoral head-neck with worse osteoarthritis • Regions of increased thickness co-locate with impingement and osteophyte formation • Quantitative 3D bone analysis could enable clinical disease prediction and therapy development.

  19. DNA Double-Strand Breaks Induce the Nuclear Actin Filaments Formation in Cumulus-Enclosed Oocytes but Not in Denuded Oocytes.

    Directory of Open Access Journals (Sweden)

    Ming-Hong Sun

    Full Text Available As a gamete, oocyte needs to maintain its genomic integrity and passes this haploid genome to the next generation. However, fully-grown mouse oocyte cannot respond to DNA double-strand breaks (DSBs effectively and it is also unable to repair them before the meiosis resumption. To compensate for this disadvantage and control the DNA repair events, oocyte needs the cooperation with its surrounding cumulus cells. Recently, evidences have shown that nuclear actin filament formation plays roles in cellular DNA DSB repair. To explore whether these nuclear actin filaments are formed in the DNA-damaged oocytes, here, we labeled the filament actins in denuded oocytes (DOs and cumulus-enclosed oocytes (CEOs. We observed that the nuclear actin filaments were formed only in the DNA-damaged CEOs, but not in DOs. Formation of actin filaments in the nucleus was an event downstream to the DNA damage response. Our data also showed that the removal of cumulus cells led to a reduction in the nuclear actin filaments in oocytes. Knocking down of the Adcy1 gene in cumulus cells did not affect the formation of nuclear actin filaments in oocytes. Notably, we also observed that the nuclear actin filaments in CEOs could be induced by inhibition of gap junctions. From our results, it was confirmed that DNA DSBs induce the nuclear actin filament formation in oocyte and which is controlled by the cumulus cells.

  20. Current strain accumulation in the hinterland of the northwest Himalaya constrained by landscape analyses, basin-wide denudation rates, and low temperature thermochronology

    Science.gov (United States)

    Morell, Kristin D.; Sandiford, Mike; Kohn, Barry; Codilean, Alexandru; Fülöp, Réka-H.; Ahmad, Talat

    2017-11-01

    Rupture associated with the 25 April 2015 Mw 7.8 Gorkha (Nepal) earthquake highlighted our incomplete understanding of the structural architecture and seismic cycle processes that lead to Himalayan mountain building in Central Nepal. In this paper we investigate the style and kinematics of active mountain building in the Himalayan hinterland of Northwest India, approximately 400 km to the west of the hypocenter of the Nepal earthquake, via a combination of landscape metrics and long- (Ma) and short-term (ka) erosion rate estimates (from low temperature thermochronometry and basin-wide denudation rate estimates from 10Be concentrations). We focus our analysis on the area straddling the PT2, the physiographic transition between the Lesser and High Himalaya that has yielded important insights into the nature of hinterland deformation across much of the Himalaya. Our results from Northwest India reveal a distinctive PT2 that separates a Lesser Himalaya region with moderate relief (∼1000 m) and relatively slow erosion (400 km distance between them, similar spatiotemporal patterns of erosion and deformation observed in Northwest India and Central Nepal suggest both regions experience similar styles of active strain accumulation and both are susceptible to large seismic events.

  1. Tectonics and Unroofing of the Santa Cruz Mountains, California, from Low-Temperature Thermochronology and Catchment-Averaged 10Be-Derived Denudation Rates (Invited)

    Science.gov (United States)

    Hilley, G. E.; Burgmann, R.; Dumitru, T. A.; Ebert, Y.; Fosdick, J. C.; Le, K.; Levine, N. M.; Wilson, A.; Gudmundsdottir, M. H.

    2010-12-01

    We present eleven Apatite Fission Track (AFT) and Apatite (U-Th)/He (A-He) analyses and eighteen catchment-averaged cosmogenic 10Be denudation rates from the Santa Cruz Mountains (SCM) that resolve the unroofing history of this range over the past several Myr. This range lies within a restraining bend in the San Andreas Fault (SAF), which appears to be fixed to the crust on the northeast side of the fault based on previous work. In this view, the topographic asymmetry of the SCM reflects the advection of material southwest of the right-lateral SAF through a zone of uplift centered on the restraining bend, while material northwest of the fault remains trapped this zone. Northeast of the fault bend in the Sierra Azul block of the SCM, AFT ages adjacent to the SAF appear completely reset during the Pliocene, and show partial resetting at the periphery of the block. This suggests that total exhumation exceeded 3-4 km within the heart of the block and was SCM are near mass flux steady state over the timescales captured by the CRN (~1.5-6.5 ka). Nonetheless, the extent of topography in areas far from the bend suggests that there may be some component of regional fault-normal contraction and/or that this steady state has not been fully attained because of geomorphic lags and isostatic adjustments.

  2. Hemochromatosis: abnormalities of bones and joints: a case report and literature review

    International Nuclear Information System (INIS)

    Farao, S.R.F.; Pereira, E.M.; Harima, H.A.; Rocha Correa Fernandes, A. da; Pavin, A.E.

    1989-01-01

    The authors report a case of a 49 years-old male patient with emphasis in the arthropathy of hemochromatosis. The arthropathy was the first manifestation: the patient had been complaining of pain on the right hip for eight years. The other specific clinical manifestations: diabetes, abnormal pigmentation appeared after six years. The roentgenographic features of bone and joint involvement include abnormalites at metacarpophalangeal joints with osteophytes on the metacarpal heads and in the hip, joint space narrowing, was seen. In the knee involvement is characterized by subchondral cyst and osteophytosis. Laboratory analysis are: serum iron = 191 mg/dl (normal value: 50-150 mg/dl), ferritin > 400 ng/ml (normal value: 42-26 ng/ml). Iron within the parenchymal cells of the liver cirrhosis was detected by hepatic biopsy. Hemochromatosis was pathologically characterized by tissue damage produced by iron deposition. (author) [pt

  3. Microvascularity, blood flow and tissue structure at the subchondral plate using an X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Muthuvelu, P.; Ellis, R.E.; Green, E.M.; Attenburrow, D.; Arkill, K.; Colridge, D.B.; Winlove, C.P.; Bradley, D.A.

    2007-01-01

    The measurement of blood flow and blood in bone and cartilaginous tissues is crucial to understanding of the development of various diseases, but it presents a formidable technical challenge. We have therefore developed a method based on the detection of metallized microspheres using X-ray fluorescence. This approach provides unrivalled sensitivity and spatial resolution and also allows us simultaneously to measure other markers of the metabolic status of the tissue. (author)

  4. Dating of cremated bones

    NARCIS (Netherlands)

    Lanting, JN; Aerts-Bijma, AT; van der Plicht, J; Boaretto, E.; Carmi, I.

    2001-01-01

    When dating unburnt bone, bone collagen, the organic fraction of the bone, is used. Collagen does not survive the heat of the cremation pyre, so dating of cremated bone has been considered impossible. Structural carbonate in the mineral fraction of the bone, however, survives the cremation process.

  5. Malignant bone tumors

    International Nuclear Information System (INIS)

    Zedgenidze, G.A.; Kishkovskij, A.N.; Elashov, Yu.G.

    1984-01-01

    Clinicoroentgenologic semiotics of malignant bone tumors as well as metastatic bone tumors are presented. Diagnosis of malignant and metastatic bone tumors should be always complex, representing a result of cooperation of a physician, roentgenologist, pathoanatomist

  6. Bone Graft Alternatives

    Science.gov (United States)

    ... Spine Treatment Spondylolisthesis BLOG FIND A SPECIALIST Treatments Bone Graft Alternatives Patient Education Committee Patient Education Committee ... procedure such as spinal fusion. What Types of Bone Grafts are There? Bone grafts that are transplanted ...

  7. Menopause and Bone Loss

    Science.gov (United States)

    Fact Sheet & Menopause Bone Loss How are bone loss and menopause related? Throughout life your body keeps a balance between the ... lose bone faster than it can be replaced. Menopause—the time when menstrual periods end, which usually ...

  8. Bone and fat connection in aging bone.

    Science.gov (United States)

    Duque, Gustavo

    2008-07-01

    The fat and bone connection plays an important role in the pathophysiology of age-related bone loss. This review will focus on the age-induced mechanisms regulating the predominant differentiation of mesenchymal stem cells into adipocytes. Additionally, bone marrow fat will be considered as a diagnostic and therapeutic approach to osteoporosis. There are two types of bone and fat connection. The 'systemic connection', usually seen in obese patients, is hormonally regulated and associated with high bone mass and strength. The 'local connection' happens inside the bone marrow. Increasing amounts of bone marrow fat affect bone turnover through the inhibition of osteoblast function and survival and the promotion of osteoclast differentiation and activation. This interaction is regulated by paracrine secretion of fatty acids and adipokines. Additionally, bone marrow fat could be quantified using noninvasive methods and could be used as a therapeutic approach due to its capacity to transdifferentiate into bone without affecting other types of fat in the body. The bone and fat connection within the bone marrow constitutes a typical example of lipotoxicity. Additionally, bone marrow fat could be used as a new diagnostic and therapeutic approach for osteoporosis in older persons.

  9. Reconstruction of Post-Deccan topographies from mapping of relict lateritic paleosurfaces: Implications for long-term denudation of Peninsular India

    Science.gov (United States)

    Jean, Amandine; Beauvais, Anicet; Chardon, Dominique; Bonnet, Nicolas; Mudlappa, Jayananda; Janwari, Shazia; Mathé, Pierre-Etienne

    2017-04-01

    retrieved in both the lowland and the highland to reconstruct successive topographies across the WGE and estimate relief evolution and erosion budgets for major time steps. The results suggest that the denudation did not exceed 10 m/my in the Highland since 45 Ma, and is less than 11 m/my since mitigation of chemical weathering ca. 23 Ma ago. In the lowland, denudation was limited to 5 m/my since 45 Ma and less than 6 m/my since 19 Ma, implying negligible reworking of the WGE, which stabilized at least 50 Ma ago [2]. These results have major implications for relief evolution of South India. They imply very low relief growth since the Eocene and do not require a tilt of the Peninsula. They further put constraints on sedimentary supplies to both margins of the Peninsula over the last 50 Ma. [1] Bonnet et al., 2016, Chemical Geology 446, 33-53. [2] Beauvais et al., 2016, Geology 44, 299-302.

  10. Dating of cremated bones

    OpenAIRE

    Lanting, JN; Aerts-Bijma, AT; van der Plicht, J; Boaretto, E.; Carmi, I.

    2001-01-01

    When dating unburnt bone, bone collagen, the organic fraction of the bone, is used. Collagen does not survive the heat of the cremation pyre, so dating of cremated bone has been considered impossible. Structural carbonate in the mineral fraction of the bone, however, survives the cremation process. We developed a method of dating cremated bone by accelerator mass spectrometry (AMS), using this carbonate fraction. Here we present results for a variety of prehistoric sites and ages, showing a r...

  11. Minimally Manipulated Bone Marrow Concentrate Compared with Microfracture Treatment of Full-Thickness Chondral Defects: A One-Year Study in an Equine Model.

    Science.gov (United States)

    Chu, Constance R; Fortier, Lisa A; Williams, Ashley; Payne, Karin A; McCarrel, Taralyn M; Bowers, Megan E; Jaramillo, Diego

    2018-01-17

    Microfracture is commonly performed for cartilage repair but usually results in fibrocartilage. Microfracture augmented by autologous bone marrow concentrate (BMC) was previously shown to yield structurally superior cartilage repairs in an equine model compared with microfracture alone. The current study was performed to test the hypothesis that autologous BMC without concomitant microfracture improves cartilage repair compared with microfracture alone. Autologous sternal bone marrow aspirate (BMA) was concentrated using a commercial system. Cells from BMC were evaluated for chondrogenic potential in vitro and in vivo. Bilateral full-thickness chondral defects (15-mm diameter) were created on the midlateral trochlear ridge in 8 horses. Paired defects were randomly assigned to treatment with BMC without concomitant microfracture, or to microfracture alone. The repairs were evaluated at 1 year by in vitro assessment, arthroscopy, morphological magnetic resonance imaging (MRI), quantitative T2-weighted and ultrashort echo time enhanced T2* (UTE-T2*) MRI mapping, and histological assessment. Culture-expanded but not freshly isolated cells from BMA and BMC underwent cartilage differentiation in vitro. In vivo, cartilage repairs in both groups were fibrous to fibrocartilaginous at 1 year of follow-up, with no differences observed between BMC and microfracture by arthroscopy, T2 and UTE-T2* MRI values, and histological assessment (p > 0.05). Morphological MRI showed subchondral bone changes not observed by arthroscopy and improved overall outcomes for the BMC repairs (p = 0.03). Differences in repair tissue UTE-T2* texture features were observed between the treatment groups (p BMC was applied directly to critical-sized, full-thickness chondral defects in an equine model, the cartilage repair results were similar to those of microfracture. Our data suggest that, given the few mesenchymal stem cells in minimally manipulated BMC, other mechanisms such as paracrine, anti

  12. Estimating background denudation rates and delivery of landslide sediment from a time series of 10Be concentrations in landslide dominated basins in the southern Central Range of Taiwan

    Science.gov (United States)

    Chen, C. Y.; Willett, S.; West, A. J.; Dadson, S. J.; Hovius, N.; Christl, M.; Shyu, J. B. H.

    2017-12-01

    The southern Central Range of Taiwan is located at a tectonic transition zone between an oceanic subduction zone and the arc-continent collision forming the Taiwan orogen. The rapidly evolving tectonic setting, tropical climate and frequent typhoons result in a complex uplift pattern, transient landscapes and extensive landslides. For this study, we obtained a series of 10Be concentrations over the last decade for 13 major drainage basins in the southern Central Range, bracketing the occurrence of a major typhoon, Morakot, which hit Taiwan in 2009 and triggered thousands of landslides. This time series allows us to simultaneously estimate the background erosion rate and assess the impact of Morakot-triggered landslides on 10Be concentrations. The time series of 10Be concentrations shows temporally lower concentrations of 10Be indicating dilution following the Morakot event in most basins. The diluted 10Be concentrations imply erosion rates up to three times higher than the lowest measured rates in the same basins. We constructed a simple sediment-mixing model parameterized by a sudden input of sediment supplied from landslides superimposed on a background denudation rate. This model was calibrated to measured landslide inventories and the series of 10Be data. We obtain a range of permissible background erosion rate and fraction of landslide sediments over time for each basin. The inferred background erosion rate reveals a northward increasing trend, reflecting the initial stage of the mountain building and indicating tectonic forcing is the main driver of the landscape evolution in the southern Central Range. The temporal changes in fraction of landslide sediments show that the available landslide material generated by the Morakot event is decreasing over time with a timescale of several years.

  13. Modic (endplate) changes in the lumbar spine: bone micro-architecture and remodelling.

    Science.gov (United States)

    Perilli, Egon; Parkinson, Ian H; Truong, Le-Hoa; Chong, Kuan C; Fazzalari, Nicola L; Osti, Orso L

    2015-09-01

    In the literature, inter-vertebral MRI signal intensity changes (Modic changes) were associated with corresponding histological observations on endplate biopsies. However, tissue-level studies were limited. No quantitative histomorphometric study on bone biopsies has yet been conducted for Modic changes. The aim of this study was to characterise the bone micro-architectural parameters and bone remodelling indices associated with Modic changes. Forty patients suffering from disabling low back pain, undergoing elective spinal surgery, and exhibiting Modic changes on MRI (Modic 1, n = 9; Modic 2, n = 25; Modic 3, n = 6), had a transpedicular vertebral body biopsy taken of subchondral bone. Biopsies were first examined by micro-CT, for 3D morphometric analysis of bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular separation, trabecular number, and structure model index. Then, samples underwent histological analysis, for determination of bone remodelling indices: osteoid surface to bone surface ratio (OS/BS), eroded surface to bone surface (ES/BS) and osteoid surface to eroded surface ratio (OS/ES). Micro-CT analysis revealed significantly higher BV/TV (up to 70% increase, p < 0.01) and Tb.Th (up to +57%, p < 0.01) in Modic 3 biopsies, compared to Modic 1 and 2. Histological analysis showed significantly lower OS/BS in Modic 2 biopsies (more than 28% decrease, p < 0.05) compared to 1 and 3. ES/BS progressively decreased from Modic 1 to 2 to 3, whereas OS/ES progressively increased with significantly higher values in Modic 3 (up to 159% increase, p < 0.05) than in Modic 1 and 2. Significant differences were found in bone micro-architectural parameters and remodelling indices among Modic types. Modic 1 biopsies had evidence of highest bone turnover, possibly due to an inflammatory process; Modic 2 biopsies were consistent with a reduced bone formation/remodelling stage; Modic 3 biopsies suggested a more stable sclerotic phase, with significantly

  14. Comparison of Techniques for Preimplantation Treatment of Osteochondral Allograft Bone.

    Science.gov (United States)

    Baumann, Charles A; Baumann, John R; Bozynski, Chantelle C; Stoker, Aaron M; Stannard, James P; Cook, James L

    2018-03-07

    Articular defects are a major problem with few effective treatment options. Osteochondral allograft (OCA) transplantation can be an effective treatment; however, lack of OCA bone integration can cause failure. This controlled laboratory study was designed to compare clinically applicable methods for marrow element removal and enhanced delivery of bone marrow aspirate concentrate (BMC) to OCA bone. We hypothesized that compressed carbon dioxide (CO 2 ) treatment of OCA bone would result in significantly better marrow element removal, significantly more retention and distribution of viable osteoprogenitor cells, and significantly higher osteoinductive protein elution from OCAs compared with other preimplantation treatments. Fresh humeral heads ( n  = 24) were harvested and stored for 14 days, then randomly assigned to treatment based on marrow element removal and bone treatment: (standard of care [SOC]) ( n  = 4) - SOC high-pulse saline lavage, no BMC; (BMC) ( n  = 5) - saline lavage then canine BMC; (Drill + BMC) ( n  = 5) - 1.1 mm drill-hole immediately subchondral then saline lavage then BMC injection through drill hole; (Carb + BMC) ( n  = 5) - saline lavage then CO 2 then BMC; or (Saline-Carb + BMC) ( n  = 5) - saline lavage and CO 2 together then BMC. Treated OCAs were cultured for 14 days. On day 3, media were collected, centrifuged to isolate cells, and replaced. Cells were cultured for 11 days for colony forming unit (CFU) determination. OCA media were collected on days 7 and 14 of culture for analysis. On day 14, each graft was assessed for viable cell retention and distribution, and bone marrow element removal. BMC had significantly higher ( p  = 0.001) viable cell distribution compared with the SOC, Drill + BMC, Carb + BMC, and Saline-Carb + BMC groups. BMC and Drill + BMC had significantly higher ( p  BMC, and Saline-Carb + BMC. Drill + BMC and Carb + BMC had the highest media

  15. Bone grafting: An overview

    Directory of Open Access Journals (Sweden)

    D. O. Joshi

    2010-08-01

    Full Text Available Bone grafting is the process by which bone is transferred from a source (donor to site (recipient. Due to trauma from accidents by speedy vehicles, falling down from height or gunshot injury particularly in human being, acquired or developmental diseases like rickets, congenital defects like abnormal bone development, wearing out because of age and overuse; lead to bone loss and to replace the loss we need the bone grafting. Osteogenesis, osteoinduction, osteoconduction, mechanical supports are the four basic mechanisms of bone graft. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. An ideal bone graft material is biologically inert, source of osteogenic, act as a mechanical support, readily available, easily adaptable in terms of size, shape, length and replaced by the host bone. Except blood, bone is grafted with greater frequency. Bone graft indicated for variety of orthopedic abnormalities, comminuted fractures, delayed unions, non-unions, arthrodesis and osteomyelitis. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. By adopting different procedure of graft preservation its antigenicity can be minimized. The concept of bone banking for obtaining bone grafts and implants is very useful for clinical application. Absolute stability require for successful incorporation. Ideal bone graft must possess osteogenic, osteoinductive and osteocon-ductive properties. Cancellous bone graft is superior to cortical bone graft. Usually autologous cancellous bone graft are used as fresh grafts where as allografts are employed as an alloimplant. None of the available type of bone grafts possesses all these properties therefore, a single type of graft cannot be recomm-ended for all types of orthopedic abnormalities. Bone grafts and implants can be selected as per clinical problems, the equipments available and preference of

  16. Bone scan in rheumatology

    International Nuclear Information System (INIS)

    Morales G, R.; Cano P, R.; Mendoza P, R.

    1993-01-01

    In this chapter a revision is made concerning different uses of bone scan in rheumatic diseases. These include reflex sympathetic dystrophy, osteomyelitis, spondyloarthropaties, metabolic bone diseases, avascular bone necrosis and bone injuries due to sports. There is as well some comments concerning pediatric pathology and orthopedics. (authors). 19 refs., 9 figs

  17. Bone Marrow Diseases

    Science.gov (United States)

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains stem cells. The stem cells can ... the platelets that help with blood clotting. With bone marrow disease, there are problems with the stem ...

  18. Bone grafts in dentistry

    Directory of Open Access Journals (Sweden)

    Prasanna Kumar

    2013-01-01

    Full Text Available Bone grafts are used as a filler and scaffold to facilitate bone formation and promote wound healing. These grafts are bioresorbable and have no antigen-antibody reaction. These bone grafts act as a mineral reservoir which induces new bone formation.

  19. Synchrotron and ion beam studies of the bone-cartilage interface

    International Nuclear Information System (INIS)

    Bradley, D.A.; Kaabar, W.; Gundogdu, O.; Farquharson, M.J.; Janousch, M.; Bailey, M.; Jeynes, C.

    2010-01-01

    The divalent cations Ca, P and Zn have been reported to play an important role in the normal growth and remodelling of articular cartilage and subchondral bone and in the degenerative and inflammatory processes associated with osteoarthritis (OA). In particular, they act as co-factors of a class of enzymes known as metalloproteinases, believed to be active during the initiation, progress and remodelling processes associated with the disease. The relative presence of cations and anions, in particular the ions Na 2+ and Cl - , is also intimately associated with the fixed charge density (FCD) of cartilage, neutralizing the highly charged structure associated with for instance chondroitin sulphate. Finally, structural components of bone can be expected to result from dietary intake, yielding for instance strontium apatite and fluorapatite that form inclusions in the calcium hydroxyapatite of bone. In the present investigation, thin sections of articular cartilage affected by OA have been examined using a combination of physical techniques: low energy synchrotron micro X-ray fluorescence (μ-SXRF), micro proton induced X-ray emission (μ-PIXE) and micro proton-induced gamma emission (μ-PIGE), primarily to investigate the distribution of essential cations and anions. The combination of these physical techniques offers the ability to make comprehensive assessment of the elemental content of such tissues, simultaneous mappings of a range of relatively low atomic number ions being obtained over quite large areas (∼few mm 2 ). Such capability has only become a realistic prospect in recent times.

  20. A multiscale framework based on the physiome markup languages for exploring the initiation of osteoarthritis at the bone-cartilage interface.

    Science.gov (United States)

    Shim, Vickie B; Hunter, Peter J; Pivonka, Peter; Fernandez, Justin W

    2011-12-01

    The initiation of osteoarthritis (OA) has been linked to the onset and progression of pathologic mechanisms at the cartilage-bone interface. Most importantly, this degenerative disease involves cross-talk between the cartilage and subchondral bone environments, so an informative model should contain the complete complex. In order to evaluate this process, we have developed a multiscale model using the open-source ontologies developed for the Physiome Project with cartilage and bone descriptions at the cellular, micro, and macro levels. In this way, we can effectively model the influence of whole body loadings at the macro level and the influence of bone organization and architecture at the micro level, and have cell level processes that determine bone and cartilage remodeling. Cell information is then passed up the spatial scales to modify micro architecture and provide a macro spatial characterization of cartilage inflammation. We evaluate the framework by linking a common knee injury (anterior cruciate ligament deficiency) to proinflammatory mediators as a possible pathway to initiate OA. This framework provides a "virtual bone-cartilage" tool for evaluating hypotheses, treatment effects, and disease onset to inform and strengthen clinical studies.

  1. A structural study of bone changes in knee osteoarthritis by synchrotron-based X-ray fluorescence and X-ray absorption spectroscopy techniques

    Science.gov (United States)

    Sindhupakorn, Bura; Thienpratharn, Suwittaya; Kidkhunthod, Pinit

    2017-10-01

    Osteoarthritis (OA) is characterized by degeneration of articular cartilage and thickening of subchondral bone. The present study investigated the changing of biochemical components of cartilage and bone compared between normal and OA people. Using Synchrotron-based X-ray fluorescence (SR-XRF) and X-ray absorption spectroscopy (XAS) techniquesincluding X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) were employed for the bone changes in kneeosteoarthritisstudies. The bone samples were collected from various osteoarthritis patients with both male and female in the ages range between 20 and 74 years old. SR-XRF results excited at 4240 eV for Ca elements show a majority three main groups, based on their XRF intensities, 20-36 years, 40-60 years and over 70 years, respectively. By employing XAS techniques, XANES features can be used to clearly explain in term of electronic transitions occurring in bone samples which are affected from osteoarthritis symptoms. Moreover, a structural change around Ca ions in bone samples is obviously obtained by EXAFS results indicating an increase of Ca-amorphous phase when the ages increase.

  2. Application of bone scintigraphy

    International Nuclear Information System (INIS)

    Rondain, J.E.S.

    1996-01-01

    Bone scanning has varied applications, particularly in the file of oncology. It is used in the diagnosis and follow-up of patients with cancers that metastatize to the bones (breast, prostate CA), also in primary bone cancers, infections of the bones and joints. In early stages of primary breast CA (stage I and II), the incidence of unsuspected bone metastasis is only 1-5%. On the other hand, bone scans serve as a baseline study if bone mets occur at some later stage. In patients with stage II and III breast CA, the conversion from normal to abnormal bone scans is 15% and 17%, respectively, clearly in favor of a baseline bone scan. For prostate CA, bone scanning should be used in conjunction with PSA level determination. In advanced disease, a bone scan will define the extent of the metastases, show problematic lesions in weight-bearing bones, and even allow us to evaluate response to therapy in follow-up bone scans. In patients with lung CA, a positive bone scan will make surgery of the primary lesion inappropriate. For other cancers, a bone scan maybe used if there are other signs, whether clinical or chemical, indicating bone involvement. In patients with GIT, liver, skin, brain or bladder CA, routine bone scanning may be considered superfluous. For patients with suspected infection, a 3-phase bone scan is more desirable. In patients with septic arthritis, the bones of each side of the joint take up the radiopharmaceutical while in patients with cellulitis without bony involvement, only the first two phases (dynamic and bloodpool images) will be abnormal. Bone scanning is also used in avascular lesions such as Legg-calve-Perthes disease where one will see reduced uptake of Tc99m MDP. The advent of SPECT imaging has greatly increased the sensitivity in diagnosing AVN. (author)

  3. Vladimir Byurchiev, Ankle Bones

    OpenAIRE

    Churyumov, Anton

    2017-01-01

    Vladimir says that today not many children play with ankle bones. He recalls when he was young, children played with bones more often. According to Vladimir, various games using ankle bones develop flexibility, agility, and muscle in children’s hands. Ankles bones are taken from the back legs of a cow or a sheep. It is possible to determine the age and health of animals by examining this particular bone. Arcadia

  4. Subchondral insufficiency fracture of the knee: A recognizable associated soft tissue edema pattern and a similar distribution among men and women

    Energy Technology Data Exchange (ETDEWEB)

    Wilmot, Andrew S., E-mail: wilmotas@upmc.edu [Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States); Department of Radiology, UPMC Department of Radiology, 200 Lothrop Street, UPMC Montefiore, Room NE 595, Pittsburgh, PA 15213 (United States); Ruutiainen, Alexander T., E-mail: aruutiainen@gmail.com [Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States); Michael J. Crescenz VA Medical Center in Philadelphia, 3900 Woodland Avenue, Philadelphia, PA 19104 (United States); Bakhru, Prashant T., E-mail: ptbakhru@gmail.com [Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States); Princeton Radiology Associates, Kendall Park, NJ 08824 (United States); Schweitzer, Mark E., E-mail: Mark.Schweitzer@stonybrookmedicine.edu [Stonybrook “University Medical Center, Stonybrook, NY (United States); Shabshin, Nogah, E-mail: shabshin@gmail.com [Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States); Department of Radiology, HaEmek Medical Center, Afula (Israel)

    2016-11-15

    Highlights: • Almost all MRI studies of SIFK demonstrate posterior soft tissue edema. • The posterior soft tissue edema has a recognizable pattern. • The incidence of SIFK is equally distributed among makes and females. • Meniscus extrusion is associated with SIFK progresses. - Abstract: Objective: Primary: to describe the presence and pattern of soft tissue edema in subchondral insufficiency fractures of the knee (SIFK). Secondary: to investigate the gender distribution and identify factors associated with disease progression. Methods: MR images of 74 SIFKs in 74 patients were retrospectively reviewed for soft tissue edema presence and location, meniscal tears and extrusion and synovitis. The clinical records were reviewed for age, gender, and BMI. Follow up examinations were reviewed to assess for progression. Data were analyzed for gender distribution and for association between each imaging finding as a predictor of SIFK location and progression. Results: Soft tissue edema was present in 89% (66/74) of SIFK. It was located around the MCL in 78% (58/74), posterior to and abutting on the posterior distal femur in 68% (50/74), around to the tibia in only 18% (13/74), but when present it strongly predicted the presence of a medial tibial plateau SIFK (p = 5.6 ×.

  5. Subchondral insufficiency fracture of the knee: A recognizable associated soft tissue edema pattern and a similar distribution among men and women

    International Nuclear Information System (INIS)

    Wilmot, Andrew S.; Ruutiainen, Alexander T.; Bakhru, Prashant T.; Schweitzer, Mark E.; Shabshin, Nogah

    2016-01-01

    Highlights: • Almost all MRI studies of SIFK demonstrate posterior soft tissue edema. • The posterior soft tissue edema has a recognizable pattern. • The incidence of SIFK is equally distributed among makes and females. • Meniscus extrusion is associated with SIFK progresses. - Abstract: Objective: Primary: to describe the presence and pattern of soft tissue edema in subchondral insufficiency fractures of the knee (SIFK). Secondary: to investigate the gender distribution and identify factors associated with disease progression. Methods: MR images of 74 SIFKs in 74 patients were retrospectively reviewed for soft tissue edema presence and location, meniscal tears and extrusion and synovitis. The clinical records were reviewed for age, gender, and BMI. Follow up examinations were reviewed to assess for progression. Data were analyzed for gender distribution and for association between each imaging finding as a predictor of SIFK location and progression. Results: Soft tissue edema was present in 89% (66/74) of SIFK. It was located around the MCL in 78% (58/74), posterior to and abutting on the posterior distal femur in 68% (50/74), around to the tibia in only 18% (13/74), but when present it strongly predicted the presence of a medial tibial plateau SIFK (p = 5.6 ×

  6. Local sustained delivery of acetylsalicylic acid via hybrid stent with biodegradable nanofibers reduces adhesion of blood cells and promotes reendothelialization of the denuded artery

    Directory of Open Access Journals (Sweden)

    Lee CH

    2014-01-01

    release high concentrations of acetylsalicylic acid for three weeks. The in vivo efficacy of local delivery of acetylsalicylic acid in reducing platelet and monocyte adhesion, and the minimum tissue inflammatory reaction caused by the hybrid stents in treating denuded rabbit arteries, are documented. The proposed hybrid stent, with biodegradable acetylsalicylic acid-loaded nanofibers, substantially contributed to local, sustained delivery of drugs to promote re-endothelialization and reduce thrombogenicity in the injured artery. The stents may have potential applications in the local delivery of cardiovascular drugs. Furthermore, the use of hybrid stents with acetylsalicylic acid-loaded nanofibers that have high drug loadings may provide insight into the treatment of patients with high risk of acute stent thromboses.Keywords: biodegradable drug-eluting nanofibers, acetylsalicylic acid, release characteristics, cell adhesion to vascular stents

  7. Abiotic factors affect the recruitment and biomass of perennial grass and evergreen shrub seedlings in denuded areas of Patagonian Monte rangelands.

    Science.gov (United States)

    Bosco, Tomás; Bertiller, Mónica Beatriz; Carrera, Analía Lorena

    2018-07-15

    Assessing the ability of key species to cope with environmental stresses in disturbed areas is an important issue for recovery of degraded arid ecosystem. Our objective was to evaluate the effect of soil moisture, exposure to UV radiation, and presence/absence of litter with different chemistry on soil N, recruitment and biomass of seedlings of perennial grass (Poa ligularis and Nassella tenuis) and evergreen shrub species (Atriplex lampa and Larrea divaricata) in denuded areas. We carried out a microcosm experiment with soil blocks (28 cm depth) sowed with seeds of the target species, subjected to different levels of litter type (perennial grass-evergreen shrub mixture, evergreen shrub mixture, and no litter), UV radiation (near ambient and reduced UV), and soil water (high: 15-25% and low 5-15%). Periodically, during 6 months, we assessed soil-N (total and inorganic) at two depths and species seedling recruitment at microcosms. Additionally, emerged seedlings of each species were transplanted to individual pots containing soil and subjected to the same previous factors during 12 months. Then, all plants were harvested and biomass assessed. Only inorganic soil-N at the upper soil varied among treatments increasing with the presence of evergreen shrub litter, exposure to ambient UV, and high soil water. Inorganic soil-N, promoted by near ambient UV and high soil water, had a positive effect on recruitment of perennial grasses and A. lampa. Both litter types promoted the recruitment of perennial grasses. Evergreen shrub litter and high soil water promoted the recruitment of L. divaricata. Seedling biomass of perennial grasses increased with high soil water and reduced UV. Ambient UV had positive or null effects on biomass of evergreen shrub seedlings. High soil water increased biomass of L. divaricata seedlings. We concluded that soil water appeared as the most limiting factor for seedling recruitment of all species whereas inorganic soil N limited the

  8. Anorexia Nervosa and Bone

    Science.gov (United States)

    Misra, Madhusmita; Klibanski, Anne

    2014-01-01

    Anorexia nervosa (AN) is a condition of severe low weight that is associated with low bone mass, impaired bone structure and reduced bone strength, all of which contribute to increased fracture risk., Adolescents with AN have decreased rates of bone accrual compared with normal-weight controls, raising addition concerns of suboptimal peak bone mass and future bone health in this age group. Changes in lean mass and compartmental fat depots, hormonal alterations secondary to nutritional factors contribute to impaired bone metabolism in AN. The best strategy to improve bone density is to regain weight and menstrual function. Oral estrogen-progesterone combinations are not effective in increasing bone density in adults or adolescents with AN, and transdermal testosterone replacement is not effective in increasing bone density in adult women with AN. However, physiologic estrogen replacement as transdermal estradiol with cyclic progesterone does increase bone accrual rates in adolescents with AN to approximate that in normal-weight controls, leading to a maintenance of bone density Z-scores. A recent study has shown that risedronate increases bone density at the spine and hip in adult women with AN. However, bisphosphonates should be used with great caution in women of reproductive age given their long half-life and potential for teratogenicity, and should be considered only in patients with low bone density and clinically significant fractures when non-pharmacological therapies for weight gain are ineffective. Further studies are necessary to determine the best therapeutic strategies for low bone density in AN. PMID:24898127

  9. Controlled release of celecoxib inhibits inflammation, bone cysts and osteophyte formation in a preclinical model of osteoarthritis.

    Science.gov (United States)

    Tellegen, A R; Rudnik-Jansen, I; Pouran, B; de Visser, H M; Weinans, H H; Thomas, R E; Kik, M J L; Grinwis, G C M; Thies, J C; Woike, N; Mihov, G; Emans, P J; Meij, B P; Creemers, L B; Tryfonidou, M A

    2018-11-01

    Major hallmarks of osteoarthritis (OA) are cartilage degeneration, inflammation and osteophyte formation. COX-2 inhibitors counteract inflammation-related pain, but their prolonged oral use entails the risk for side effects. Local and prolonged administration in biocompatible and degradable drug delivery biomaterials could offer an efficient and safe treatment for the long-term management of OA symptoms. Therefore, we evaluated the disease-modifying effects and the optimal dose of polyesteramide microspheres delivering the COX-2 inhibitor celecoxib in a rat OA model. Four weeks after OA induction by anterior cruciate ligament transection and partial medial meniscectomy, 8-week-old female rats (n = 6/group) were injected intra-articular with celecoxib-loaded microspheres at three dosages (0.03, 0.23 or 0.39 mg). Unloaded microspheres served as control. During the 16-week follow-up, static weight bearing and plasma celecoxib concentrations were monitored. Post-mortem, micro-computed tomography and knee joint histology determined progression of synovitis, osteophyte formation, subchondral bone changes, and cartilage integrity. Systemic celecoxib levels were below the detection limit 6 days upon delivery. Systemic and local adverse effects were absent. Local delivery of celecoxib reduced the formation of osteophytes, subchondral sclerosis, bone cysts and calcified loose bodies, and reduced synovial inflammation, while cartilage histology was unaffected. Even though the effects on pain could not be evualated directly in the current model, our results suggest the application of celecoxib-loaded microspheres holds promise as novel, safe and effective treatment for inflammation and pain in OA.

  10. Roentgenological semiotics of bone and bone joints pathology

    International Nuclear Information System (INIS)

    Zedgenidze, G.A.; Kishkovskij, A.N.; Elashov, Yu.G.

    1984-01-01

    Physiologic and pathologic processes in bones followed by alternations of bone structure and reflected on roentgenograms are considered and described. Most frequent reasons for roentgenodiagnosis errors in diseases of bone and bone joint apparatus are presented

  11. Characterization of an Ex vivo Femoral Head Model Assessed by Markers of Bone and Cartilage Turnover

    Science.gov (United States)

    Madsen, Suzi Hoegh; Goettrup, Anne Sofie; Thomsen, Gedske; Christensen, Søren Tvorup; Schultz, Nikolaj; Henriksen, Kim; Bay-Jensen, Anne-Christine; Karsdal, Morten Asser

    2011-01-01

    Objective: The pathophysiology of osteoarthritis involves the whole joint and is characterized by cartilage degradation and altered subchondral bone turnover. At present, there is a need for biological models that allow investigation of the interactions between the key cellular players in bone/cartilage: osteoblasts, osteoclasts, and chondrocytes. Methods: Femoral heads from 3-, 6-, 9-, and 12-week-old female mice were isolated and cultured for 10 days in serum-free media in the absence or presence of IGF-I (100 nM) (anabolic stimulation) or OSM (10 ng/mL) + TNF-α (20 ng/mL) (catabolic stimulation). Histology on femoral heads before and after culture was performed, and the growth plate size was examined to evaluate the effects on cell metabolism. The conditioned medium was examined for biochemical markers of bone and cartilage degradation/formation. Results: Each age group represented a unique system regarding the interest of bone or cartilage metabolism. Stimulation over 10 days with OSM + TNF-α resulted in depletion of proteoglycans from the cartilage surface in all ages. Furthermore, OSM + TNF-α decreased growth plate size, whereas IGF-I increased the size. Measurements from the conditioned media showed that OSM + TNF-α increased the number of osteoclasts by approximately 80% and induced bone and cartilage degradation by approximately 1200% and approximately 2600%, respectively. Stimulation with IGF-I decreased the osteoclast number and increased cartilage formation by approximately 30%. Conclusion: Biochemical markers and histology together showed that the catabolic stimulation induced degradation and the anabolic stimulation induced formation in the femoral heads. We propose that we have established an explant whole-tissue model for investigating cell-cell interactions, reflecting parts of the processes in the pathogenesis of joint degenerative diseases. PMID:26069585

  12. A novel bio-inorganic bone implant containing deglued bone

    Indian Academy of Sciences (India)

    With the aim of developing an ideal bone graft, a new bone grafting material was developed using deglued bone, chitosan and gelatin. Deglued bone (DGB) which is a by-product of bone glue industries and has the close crystallographic similarities of hydroxyapatite was used as main component in the preparation of bone ...

  13. Smoking and Bone Health

    Science.gov (United States)

    ... consequences because building healthy bones in youth helps prevent osteoporosis and fractures later in life. However, it is never too late to adopt new habits for healthy bones. Smoking and Osteoporosis Cigarette smoking was first identified as ...

  14. Medicines and Bone Loss

    Science.gov (United States)

    ... The doses of thyroid hormone used to treat hypothyroidism (underactive thyroid) don’t harm bone and shouldn’t be cause for concern. Only high doses, used for thyroid cancer treatment, can cause bone loss. High doses or long- ...

  15. Bone substitute biomaterials

    CERN Document Server

    Mallick, K

    2014-01-01

    Bone substitute biomaterials are fundamental to the biomedical sector, and have recently benefitted from extensive research and technological advances aimed at minimizing failure rates and reducing the need for further surgery. This book reviews these developments, with a particular focus on the desirable properties for bone substitute materials and their potential to encourage bone repair and regeneration. Part I covers the principles of bone substitute biomaterials for medical applications. One chapter reviews the quantification of bone mechanics at the whole-bone, micro-scale, and non-scale levels, while others discuss biomineralization, osteoductivization, materials to fill bone defects, and bioresorbable materials. Part II focuses on biomaterials as scaffolds and implants, including multi-functional scaffolds, bioceramics, and titanium-based foams. Finally, Part III reviews further materials with the potential to encourage bone repair and regeneration, including cartilage grafts, chitosan, inorganic poly...

  16. Radioactivity of bone cement

    International Nuclear Information System (INIS)

    Scherer, M.A.; Winkler, R.; Ascherl, R.; Lenz, E.

    1993-01-01

    A total of 14 samples of different types of bone cement from five different manufacturers were examined for their radioactivity. Each of the investigated bone cements showed a low radioactivity level, i.e. between [de

  17. Bone mineral density test

    Science.gov (United States)

    BMD test; Bone density test; Bone densitometry; DEXA scan; DXA; Dual-energy x-ray absorptiometry; p-DEXA; Osteoporosis - BMD ... need to undress. This scan is the best test to predict your risk of fractures, especially of ...

  18. What causes bone loss?

    Science.gov (United States)

    ... Paula FJA, Black DM, Rosen CJ. Osteoporosis and bone biology. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology . 13th ed. Philadelphia, PA: ... HM. Bone development and remodeling. In: Jameson JL, De Groot ...

  19. Gracile bone dysplasias

    International Nuclear Information System (INIS)

    Kozlowski, Kazimierz; Masel, John; Sillence, David O.; Arbuckle, Susan; Juttnerova, Vera

    2002-01-01

    Gracile bone dysplasias constitute a group of disorders characterised by extremely slender bones with or without fractures. We report four newborns, two of whom showed multiple fractures. Two babies had osteocraniostenosis and one had features of oligohydramnios sequence. The diagnosis in the fourth newborn, which showed thin long bones and clavicles and extremely thin, poorly ossified ribs, is uncertain. Exact diagnosis of a gracile bone dysplasia is important for genetic counselling and medico-legal reasons. (orig.)

  20. Gracile bone dysplasias

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, Kazimierz [Department of Medical Imaging, The Children' s Hospital at Westmead, Locked Bag 4001, Westmead 2145, NSW (Australia); Masel, John [Department of Radiology, Royal Children' s Hospital, Brisbane (Australia); Sillence, David O. [Department of Paediatrics and Child Health, The University of Sydney (Australia); Arbuckle, Susan [Department of Anatomical Pathology, The Children' s Hospital at Westmead, NSW (Australia); Juttnerova, Vera [Oddeleni Lekarske Genetiky, Hradec Kralove (Czech Republic)

    2002-09-01

    Gracile bone dysplasias constitute a group of disorders characterised by extremely slender bones with or without fractures. We report four newborns, two of whom showed multiple fractures. Two babies had osteocraniostenosis and one had features of oligohydramnios sequence. The diagnosis in the fourth newborn, which showed thin long bones and clavicles and extremely thin, poorly ossified ribs, is uncertain. Exact diagnosis of a gracile bone dysplasia is important for genetic counselling and medico-legal reasons. (orig.)

  1. Bone cysts: unicameral and aneurysmal bone cyst.

    Science.gov (United States)

    Mascard, E; Gomez-Brouchet, A; Lambot, K

    2015-02-01

    Simple and aneurysmal bone cysts are benign lytic bone lesions, usually encountered in children and adolescents. Simple bone cyst is a cystic, fluid-filled lesion, which may be unicameral (UBC) or partially separated. UBC can involve all bones, but usually the long bone metaphysis and otherwise primarily the proximal humerus and proximal femur. The classic aneurysmal bone cyst (ABC) is an expansive and hemorrhagic tumor, usually showing characteristic translocation. About 30% of ABCs are secondary, without translocation; they occur in reaction to another, usually benign, bone lesion. ABCs are metaphyseal, excentric, bulging, fluid-filled and multicameral, and may develop in all bones of the skeleton. On MRI, the fluid level is evocative. It is mandatory to distinguish ABC from UBC, as prognosis and treatment are different. UBCs resolve spontaneously between adolescence and adulthood; the main concern is the risk of pathologic fracture. Treatment in non-threatening forms consists in intracystic injection of methylprednisolone. When there is a risk of fracture, especially of the femoral neck, surgery with curettage, filling with bone substitute or graft and osteosynthesis may be required. ABCs are potentially more aggressive, with a risk of bone destruction. Diagnosis must systematically be confirmed by biopsy, identifying soft-tissue parts, as telangiectatic sarcoma can mimic ABC. Intra-lesional sclerotherapy with alcohol is an effective treatment. In spinal ABC and in aggressive lesions with a risk of fracture, surgical treatment should be preferred, possibly after preoperative embolization. The risk of malignant transformation is very low, except in case of radiation therapy. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  2. Characterisation of mineralisation of bone and cartilage: X-ray diffraction and Ca and Sr K{sub {alpha}} X-ray fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D.A. [Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH (United Kingdom)], E-mail: d.a.bradley@surrey.ac.uk; Muthuvelu, P.; Ellis, R.E.; Green, E.M.; Attenburrow, D. [Biomedical Physics Group, School of Physics, University of Exeter, Exeter (United Kingdom); Barrett, R. [ESRF, BP 220, F-38043 Grenoble Cedex (France); Arkill, K.; Colridge, D.B.; Winlove, C.P. [Biomedical Physics Group, School of Physics, University of Exeter, Exeter (United Kingdom)

    2007-10-15

    Bone is a dynamic structure, constantly remodelling in response to changing mechanical and environmental factors. This is particularly evident in the mineral component encrusting the collagenous framework. The mineral is principally in the form of calcium apatite, but calcium can exchange with strontium, both during the cellular processes of mineralisation and resorption and by passive exchange with the deposited crystals. Mineralisation is generally characterized by densitometry, but because of the differences in absorption cross sections of calcium and strontium it can be misleading in studies of composition. In this work we have used X-ray diffraction to identify calcium and strontium apatite and X-ray fluorescence to quantify strontium and calcium distribution. With the beam characteristics available from synchrotron radiation, this has enabled us to obtain microscopic resolution on thin sections of bone and cartilage from the equine metacarpophalangeal joint. Two issues have been investigated; the first is the distribution of mineral in the bone-cartilage interface and within individual trabeculae. In trabecular bone the ratio of strontium to calcium concentration was typically 0.0035 {+-} 0.0020, and higher by a factor of {approx}3 at the periphery than in the centre of a trabeculum (possibly reflecting the more rapid turnover of mineral in the surface layer). In the dense subchondral bone the ratio was similar, approximately doubling in the calcified cartilage. The second objective was to explore the changes in mineralisation associated with development of osteoarthrosis. We analysed lesions showing cartilage thinning and changes in the trabecular organization and density of the underlying bone. At the centre of the lesion the ratio of strontium to calcium was much lower than that in normal tissue, although the calcified cartilage still showed a higher ratio than the underlying bone. In the superficially normal tissue around the lesion the calcified

  3. (unicameral) bone cysts

    African Journals Online (AJOL)

    SA JOURNAL OF RADIOLOGY • September 2007. When encountering a radiologically benign lucent bone lesion in a child, a simple bone cyst is a reasonable diagnostic consideration. Simple or unicameral bone cysts are expansile, serous-fluid-containing defects, that are not true neoplasms. Peak age ranges between 3 ...

  4. Cortical bone metastases

    International Nuclear Information System (INIS)

    Davis, T.M. Jr.; Rogers, L.F.; Hendrix, R.W.

    1986-01-01

    Twenty-five cases of bone metastases involving the cortex alone are reviewed. Seven patients had primary lung carcinoma, while 18 had primary tumors not previously reported to produce cortical bone metastases (tumors of the breast, kidney, pancreas, adenocarcinoma of unknown origin, multiple myeloma). Radiographically, these cortical lesions were well circumscribed, osteolytic, and produced soft-tissue swelling and occasional periosteal reaction. A recurrent pattern of metadiaphyseal involvement of the long bones of the lower extremity (particularly the femur) was noted, and is discussed. Findings reported in the literature, review, pathophysiology, and the role of skeletal radiographs, bone scans, and CT scans in evaluating cortical bone metastases are addressed

  5. Cytology of Bone.

    Science.gov (United States)

    Barger, Anne M

    2017-01-01

    Cytology of bone is a useful diagnostic tool. Aspiration of lytic or proliferative lesions can assist with the diagnosis of inflammatory or neoplastic processes. Bacterial, fungal, and protozoal organisms can result in significant osteomyelitis, and these organisms can be identified on cytology. Neoplasms of bone including primary bone tumors such as osteosarcoma, chondrosarcoma, fibrosarcoma, synovial cell sarcoma, and histiocytic sarcoma and tumors of bone marrow including plasma cell neoplasia and lymphoma and metastatic neoplasia can result in significant bone lysis or proliferation and can be diagnosed effectively with cytology. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Enzymatic maceration of bone

    DEFF Research Database (Denmark)

    Uhre, Marie-Louise; Eriksen, Anne Marie; Simonsen, Kim Pilkjær

    2015-01-01

    and afterwards macerated by one of the two methods. DNA extraction was performed to see the effect of the macerations on DNA preservation. Furthermore, the bone pieces were examined in a stereomicroscope to assess for any bone damage. The results demonstrated that both methods removed all flesh/soft tissue from...... the bones. The DNA analysis showed that DNA was preserved on all the pieces of bones which were examined. Finally, the investigation suggests that enzyme maceration could be gentler on the bones, as the edges appeared less frayed. The enzyme maceration was also a quicker method; it took three hours compared...

  7. [Prefabrication of bone transplants].

    Science.gov (United States)

    Jagodzinski, M; Kokemüller, H; Jehn, P; Vogt, P; Gellrich, N-C; Krettek, C

    2015-03-01

    Prefabrication of bone transplants is a promising option for large defects of the long bones, especially if there is compromised vascularization of the defect. This is especially true for postinfection bone defects and other types of atrophic nonunion. The generation of a foreign body membrane (Masquelet's technique) has been investigated in order to ameliorate the response of the host tissue surrounding the defect. In an experimental animal study, a blood vessel within a bone construct could be used to generate customized, vascularized osteogenic constructs that can be used to treat large bone defects in the future.

  8. Otosclerosis: Temporal Bone Pathology.

    Science.gov (United States)

    Quesnel, Alicia M; Ishai, Reuven; McKenna, Michael J

    2018-04-01

    Otosclerosis is pathologically characterized by abnormal bony remodeling, which includes bone resorption, new bone deposition, and vascular proliferation in the temporal bone. Sensorineural hearing loss in otosclerosis is associated with extension of otosclerosis to the cochlear endosteum and deposition of collagen throughout the spiral ligament. Persistent or recurrent conductive hearing loss after stapedectomy has been associated with incomplete footplate fenestration, poor incus-prosthesis connection, and incus resorption in temporal bone specimens. Human temporal bone pathology has helped to define the role of computed tomography imaging for otosclerosis, confirming that computed tomography is highly sensitive for diagnosis, yet limited in assessing cochlear endosteal involvement. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Zn deposition at the bone-cartilage interface in equine articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D.A. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom)], E-mail: D.A.Bradley@surrey.ac.uk; Moger, C.J.; Winlove, C.P. [School of Physics, University of Exeter, Exeter, EX4 4QL (United Kingdom)

    2007-09-21

    In articular cartilage metalloproteinases, a family of enzymes whose function relies on the presence of divalent cations such as Zn and Ca plays a central role in the normal processes of growth and remodelling and in the degenerative and inflammatory processes of arthritis. Another important enzyme, alkaline phosphatase, involved in cartilage mineralisation also relies on metallic cofactors. The local concentration of divalent cations is therefore of considerable interest in cartilage pathophysiology and several authors have used synchrotron X-ray fluorescence (XRF) to map metal ion distributions in bone and cartilage. We report use of a bench-top XRF analytical microscope, providing spatial resolution of 10 {mu}m and applicable to histological sections, facilitating correlation of the distribution with structural features. The study seeks to establish the elemental distribution in normal tissue as a precursor to investigation of changes in disease. For six samples prepared from equine metacarpophalangeal joint, we observed increased concentration of Zn and Sr ions around the tidemark between normal and mineralised cartilage. This is believed to be an active site of remodelling but its composition has hitherto lacked detailed characterization. We also report preliminary results on two of the samples using Proton-Induced X-ray Emission (PIXE). This confirms our previous observations using synchrotron-based XRF of enhanced deposition of Sr and Zn at the surface of the subchondral bone and in articular cartilage.

  10. μ-PIXE and SAXS studies at the bone-cartilage interface

    International Nuclear Information System (INIS)

    Kaabar, W.; Gundogdu, O.; Laklouk, A.; Bunk, O.; Pfeiffer, F.; Farquharson, M.J.; Bradley, D.A.

    2010-01-01

    Micro Proton Induced X-ray Emission (μ-PIXE) analysis has been employed herein in investigating and quantifying the distribution of a number of essential elements in thin human diseased articular cartilage sections affected by osteoarthritis (OA). Various cations Ca, P and Zn have been reported to play an important role both in the normal growth and remodelling of articular cartilage and subchondral bone as well as in the degenerative and inflammatory processes associated with the disease; they act as co-factors of a class of enzymes known as metalloproteinases which are believed to be active during the initiation, progress and remodelling processes associated with osteoarthritis. Other important enzymes such as alkaline phosphatase are associated with cartilage mineralization. Synchrotron radiation X-ray fluorescence (SR-XRF) for mapping of elemental distributions in bone and cartilage has also been employed by the present group and others. In the current investigations using the cSAXS beamline at the Swiss light source, Small-Angle X-ray Scattering (SAXS) was carried out on decalcified human articular cartilage to explore the structural and organizational changes of collagen networks in diseased articular cartilage.

  11. {mu}-PIXE and SAXS studies at the bone-cartilage interface

    Energy Technology Data Exchange (ETDEWEB)

    Kaabar, W. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom)], E-mail: w.kaabar@surrey.ac.uk; Gundogdu, O. [Umuttepe Campus, University of Kocaeli, 41380, Kocaeli (Turkey); Laklouk, A. [Food Science Department, Al-Fateh Unversity, Tripoli (Libyan Arab Jamahiriya); Bunk, O. [Swiss Light Source, Paul Scherrer Institute, 5232 Villigen (Switzerland); Pfeiffer, F. [Swiss Light Source, Paul Scherrer Institute, 5232 Villigen (Switzerland); Ecole Polytechnique Federale de Lausanne, 1015 Lausanne (Switzerland); Farquharson, M.J. [Department of Radiography, City University, London EC1V OHB (United Kingdom); Bradley, D.A. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2010-04-15

    Micro Proton Induced X-ray Emission ({mu}-PIXE) analysis has been employed herein in investigating and quantifying the distribution of a number of essential elements in thin human diseased articular cartilage sections affected by osteoarthritis (OA). Various cations Ca, P and Zn have been reported to play an important role both in the normal growth and remodelling of articular cartilage and subchondral bone as well as in the degenerative and inflammatory processes associated with the disease; they act as co-factors of a class of enzymes known as metalloproteinases which are believed to be active during the initiation, progress and remodelling processes associated with osteoarthritis. Other important enzymes such as alkaline phosphatase are associated with cartilage mineralization. Synchrotron radiation X-ray fluorescence (SR-XRF) for mapping of elemental distributions in bone and cartilage has also been employed by the present group and others. In the current investigations using the cSAXS beamline at the Swiss light source, Small-Angle X-ray Scattering (SAXS) was carried out on decalcified human articular cartilage to explore the structural and organizational changes of collagen networks in diseased articular cartilage.

  12. Aneurysmal bone cyst of the temporal bone

    International Nuclear Information System (INIS)

    Buxi, Tarvinder; Sud Seema; Vohra, Rakesh; Sud, Aditi; Singh, Satnam

    2004-01-01

    Aneurysmal bone cyst (ABC) of the temporal bone is rare. The nature of the underlying disorder that converted into the ABC might, however, be difficult to ascertain on imaging as well as on histopathology. The unusual CT and MRI findings in a case of ABC of the temporal bone are presented. This had transdural intracerebral spread with a large component of solid enhancing matrix but no peripheral calcific rim. The patient was an adult of 45 years with a history of headache for more than 1 year Copyright (2004) Blackwell Publishing Asia Pty Ltd

  13. BONES WITH BIOCERAMICS

    Directory of Open Access Journals (Sweden)

    Wijianto Wijianto

    2017-01-01

    Full Text Available This paper discuss about ceramics in application as bone implant. Bioceramics for instance Hydroxyapatite, usually is abbreviated with HA or HAp, is a mineral that is very good physical properties as bone replacement in human body. To produce Hydroxyapatite, coating process is used which have good potential as they can exploit the biocompatible and bone bonding properties of the ceramic. There are many advantages and disadvantages of bioceramics as bone implant. Advantages of hydroxyapatite as bone implant are rapidly integrated into the human body, and is most interesting property that will bond to bone forming indistinguishable unions. On contrary, disadvantages of hydroxyapatite as bone implant are poor mechanical properties (in particular fatigue properties mean that hydroxyapatite cannot be used in bulk form for load bearing applications such as orthopaedics and poor adhesion between the calcium phosphate coating and the material implant will occur.

  14. Bone allografting in children

    Science.gov (United States)

    Sadovoy, M. A.; Kirilova, I. A.; Podorognaya, V. T.; Matsuk, S. A.; Novoselov, V. P.; Moskalev, A. V.; Bondarenko, A. V.; Afanasev, L. M.; Gubina, E. V.

    2017-09-01

    A total of 522 patients with benign and intermediate bone tumors of various locations, aged 1 to 15 years, were operated in the period from 1996 to 2016. To diagnose skeleton tumors, we used clinical observation, X-ray, and, if indicated, tomography and tumor site biopsy. In the extensive bone resection, we performed bone reconstruction with the replacement of a defect with an allograft (bone strips, deproteinized and spongy grafts), sometimes in the combination with bone autografting. After segmental resection, the defects were filled with bone strips in the form of matchstick grafts; the allografts were received from the Laboratory for Tissue Preparation and Preservation of the Novosibirsk Research Institute of Traumatology and Orthopedics. According to the X-ray data, a complete reorganization of bone grafts occurred within 1.5 to 3 years. The long-term result was assessed as good.

  15. Bone disease in diabetes

    DEFF Research Database (Denmark)

    Shanbhogue, Vikram V.; Hansen, Stinus; Frost, Morten

    2017-01-01

    Type 1 and type 2 diabetes are generally accepted to be associated with increased bone fracture risk. However, the pathophysiological mechanisms of diabetic bone disease are poorly understood, and whether the associated increased skeletal fragility is a comorbidity or a complication of diabetes...... remains under debate. Although there is some indication of a direct deleterious effect of microangiopathy on bone, the evidence is open to question, and whether diabetic osteopathy can be classified as a chronic, microvascular complication of diabetes remains uncertain. Here, we review the current...... knowledge of potential contributory factors to diabetic bone disease, particularly the association between diabetic microangiopathy and bone mineral density, bone structure, and bone turnover. Additionally, we discuss and propose a pathophysiological model of the effects of diabetic microvascular disease...

  16. Bone scintiscanning updated.

    Science.gov (United States)

    Lentle, B C; Russell, A S; Percy, J S; Scott, J R; Jackson, F I

    1976-03-01

    Use of modern materials and methods has given bone scintiscanning a larger role in clinical medicine, The safety and ready availability of newer agents have led to its greater use in investigating both benign and malignant disease of bone and joint. Present evidence suggests that abnormal accumulation of 99mTc-polyphosphate and its analogues results from ionic deposition at crystal surfaces in immature bone, this process being facilitated by an increase in bone vascularity. There is, also, a component of matrix localization. These factors are in keeping with the concept that abnormal scintiscan sites represent areas of increased osteoblastic activity, although this may be an oversimplification. Increasing evidence shows that the bone scintiscan is more sensitive than conventional radiography in detecting focal disease of bone, and its ability to reflect the immediate status of bone further complements radiographic findings. The main limitation of this method relates to nonspecificity of the results obtained.

  17. Inhibition of PKC-dependent extracellular Ca{sup 2+} entry contributes to the depression of contractile activity in long-term pressure-overloaded endothelium-denuded rat aortas

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, J.; López, R.M.; López, P.; Castillo, M.C.; Querejeta, E.; Ruiz, A.; Castillo, E.F. [Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, México, DF (Mexico)

    2014-08-01

    We examined the contractile responsiveness of rat thoracic aortas under pressure overload after long-term suprarenal abdominal aortic coarctation (lt-Srac). Endothelium-dependent angiotensin II (ANG II) type 2 receptor (AT{sub 2}R)-mediated depression of contractions to ANG II has been reported in short-term (1 week) pressure-overloaded rat aortas. Contractility was evaluated in the aortic rings of rats subjected to lt-Srac or sham surgery (Sham) for 8 weeks. ANG I and II levels and AT{sub 2}R protein expression in the aortas of lt-Srac and Sham rats were also evaluated. lt-Srac attenuated the contractions of ANG II and phenylephrine in the aortas in an endothelium-independent manner. However, lt-Srac did not influence the transient contractions induced in endothelium-denuded aortic rings by ANG II, phenylephrine, or caffeine in Ca{sup 2+}-free medium or the subsequent tonic constrictions induced by the addition of Ca{sup 2+} in the absence of agonists. Thus, the contractions induced by Ca{sup 2+} release from intracellular stores and Ca{sup 2+} influx through stored-operated channels were not inhibited in the aortas of lt-Srac rats. Potassium-elicited contractions in endothelium-denuded aortic rings of lt-Srac rats remained unaltered compared with control tissues. Consequently, the contractile depression observed in aortic tissues of lt-Srac rats cannot be explained by direct inhibition of voltage-operated Ca{sup 2+} channels. Interestingly, 12-O-tetradecanoylphorbol-13-acetate-induced contractions in endothelium-denuded aortic rings of lt-Srac rats were depressed in the presence but not in the absence of extracellular Ca{sup 2+}. Neither levels of angiotensins nor of AT{sub 2}R were modified in the aortas after lt-Srac. The results suggest that, in rat thoracic aortas, lt-Srac selectively inhibited protein kinase C-mediated activation of contraction that is dependent on extracellular Ca{sup 2+} entry.

  18. Indirect MR-arthrography in osteochondral autograft and crushed bone graft with a collagen membrane-Correlation with histology

    Energy Technology Data Exchange (ETDEWEB)

    Streitparth, F. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany)], E-mail: florian.streitparth@charite.de; Schoettle, P.; Schell, H. [Center for Musculoskeletal Surgery, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Lehmkuhl, L.; Madej, T.; Wieners, G. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Duda, G.N. [Center for Musculoskeletal Surgery, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Schroeder, R.J. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany)

    2009-04-15

    Objective: To analyze the spectrum of findings in indirect MR-arthrography following osteochondral autograft transfer system (OATS) and crushed bone graft using a magnetic resonance imaging (MRI) scoring and grading system in relation to histology as the standard of reference. Materials and methods: Iatrogenic lesions were set at ovine condylar facets (n = 6/group), treated with OATS or crushed bone graft. 1.5 T MRI was performed 6 months after surgery using PD-weighted (w fat saturated (fs) fast spin echo (FSE), T1-w 2D, and 3D fs gradient echo (GE) sequences 30 min. after i.v. Gd-DTPA administration and passive joint exercise. The repair tissue was evaluated by two independent radiologists. The MR findings were compared to histology. Results: In all cases, MRI and histologic grading correlated well and showed significant superior repair in OATS at 6 months (p < 0.05), reproducing the original articular contour and a good subchondral restoration. FsT1-w3DGE proved most appropriate identifying characteristic post-operative findings: the OATS group demonstrated bone marrow edema at the donor site and the graft/host interface showed significant enhancement in indirect MR-arthrography, indicating fibrocartilage. After crushed bone graft, we found an irregular structure and significant contrast uptake, consistent with remnants of bone grafts surrounded by inflammatory tissue. Conclusion: Indirect MR-arthrography is an accurate, non-invasive monitoring tool following OATS and crushed bone graft as the MRI scoring and grading system allows a reliable evaluation of normal and pathological osteochondral repair with a high histologic correlation.

  19. Autologous Bone Marrow Concentrate in a Sheep Model of Osteoarthritis: New Perspectives for Cartilage and Meniscus Repair.

    Science.gov (United States)

    Desando, Giovanna; Giavaresi, Gianluca; Cavallo, Carola; Bartolotti, Isabella; Sartoni, Federica; Nicoli Aldini, Nicolò; Martini, Lucia; Parrilli, Annapaola; Mariani, Erminia; Fini, Milena; Grigolo, Brunella

    2016-06-01

    Cell-based therapies are becoming a valuable tool to treat osteoarthritis (OA). This study investigated and compared the regenerative potential of bone marrow concentrate (BMC) and mesenchymal stem cells (MSC), both engineered with Hyaff(®)-11 (HA) for OA treatment in a sheep model. OA was induced via unilateral medial meniscectomy. Bone marrow was aspirated from the iliac crest, followed by concentration processes or cell isolation and expansion to obtain BMC and MSC, respectively. Treatments consisted of autologous BMC and MSC seeded onto HA. The regenerative potential of bone, cartilage, menisci, and synovia was monitored using macroscopy, histology, immunohistochemistry, and micro-computed tomography at 12 weeks post-op. Data were analyzed using the general linear model with adjusted Sidak's multiple comparison and Spearman's tests. BMC-HA treatment showed a greater repair ability in inhibiting OA progression compared to MSC-HA, leading to a reduction of inflammation in cartilage, meniscus, and synovium. Indeed, the decrease of inflammation positively contributed to counteract the progression of fibrotic and hypertrophic processes, known to be involved in tissue failure. Moreover, the treatment with BMC-HA showed the best results in allowing meniscus regeneration. Minor healing effects were noticed at bone level for both cell strategies; however, a downregulation of subchondral bone thickness (Cs.Th) was found in both cell treatments compared to the OA group in the femur. The transplantation of BMC-HA provided the best effects in supporting regenerative processes in cartilage, meniscus, and synovium and at less extent in bone. On the whole, both MSC and BMC combined with HA reduced inflammation and contributed to switch off fibrotic and hypertrophic processes. The observed regenerative potential by BMC-HA on meniscus could open new perspectives, suggesting its use not only for OA care but also for the treatment of meniscal lesions, even if further analyses are

  20. [Bone homeostasis and Mechano biology.

    Science.gov (United States)

    Nakashima, Tomoki

    The weight-bearing exercises help to build bones and to maintain them strength. Bone is constantly renewed by the balanced action of osteoblastic bone formation and osteoclastic bone resorption both of which mainly occur at the bone surface. This restructuring process called "bone remodeling" is important not only for normal bone mass and strength, but also for mineral homeostasis. Bone remodeling is stringently regulated by communication between bone component cells such as osteoclasts, osteoblasts and osteocytes. An imbalance of this process is often linked to various bone diseases. During bone remodeling, resorption by osteoclasts precedes bone formation by osteoblasts. Based on the osteocyte location within the bone matrix and the cellular morphology, it is proposed that osteocytes potentially contribute to the regulation of bone remodeling in response to mechanical and endocrine stimuli.

  1. Biomaterials and bone mechanotransduction

    Science.gov (United States)

    Sikavitsas, V. I.; Temenoff, J. S.; Mikos, A. G.; McIntire, L. V. (Principal Investigator)

    2001-01-01

    Bone is an extremely complex tissue that provides many essential functions in the body. Bone tissue engineering holds great promise in providing strategies that will result in complete regeneration of bone and restoration of its function. Currently, such strategies include the transplantation of highly porous scaffolds seeded with cells. Prior to transplantation the seeded cells are cultured in vitro in order for the cells to proliferate, differentiate and generate extracellular matrix. Factors that can affect cellular function include the cell-biomaterial interaction, as well as the biochemical and the mechanical environment. To optimize culture conditions, good understanding of these parameters is necessary. The new developments in bone biology, bone cell mechanotransduction, and cell-surface interactions are reviewed here to demonstrate that bone mechanotransduction is strongly influenced by the biomaterial properties.

  2. Biophotonics and Bone Biology

    Science.gov (United States)

    Zimmerli, Gregory; Fischer, David; Asipauskas, Marius; Chauhan, Chirag; Compitello, Nicole; Burke, Jamie; Tate, Melissa Knothe

    2004-01-01

    One of the more-serious side effects of extended space flight is an accelerated bone loss [Bioastronautics Critical Path Roadmap, http://research.hq.nasa.gov/code_u/bcpr/index.cfm]. Rates of bone loss are highest in the weight-bearing bones of the hip and spine regions, and the average rate of bone loss as measured by bone mineral density measurements is around 1.2% per month for persons in a microgravity environment. It shows that an extrapolation of the microgravity induced bone loss rates to longer time scales, such as a 2.5 year round-trip to Mars (6 months out at 0 g, 1.5 year stay on Mars at 0.38 g, 6 months back at 0 g), could severely compromise the skeletal system of such a person.

  3. Improved cartilage regeneration by implantation of acellular biomaterials after bone marrow stimulation: a systematic review and meta-analysis of animal studies

    Directory of Open Access Journals (Sweden)

    Michiel W. Pot

    2016-09-01

    Full Text Available Microfracture surgery may be applied to treat cartilage defects. During the procedure the subchondral bone is penetrated, allowing bone marrow-derived mesenchymal stem cells to migrate towards the defect site and form new cartilage tissue. Microfracture surgery generally results in the formation of mechanically inferior fibrocartilage. As a result, this technique offers only temporary clinical improvement. Tissue engineering and regenerative medicine may improve the outcome of microfracture surgery. Filling the subchondral defect with a biomaterial may provide a template for the formation of new hyaline cartilage tissue. In this study, a systematic review and meta-analysis were performed to assess the current evidence for the efficacy of cartilage regeneration in preclinical models using acellular biomaterials implanted after marrow stimulating techniques (microfracturing and subchondral drilling compared to the natural healing response of defects. The review aims to provide new insights into the most effective biomaterials, to provide an overview of currently existing knowledge, and to identify potential lacunae in current studies to direct future research. A comprehensive search was systematically performed in PubMed and EMBASE (via OvidSP using search terms related to tissue engineering, cartilage and animals. Primary studies in which acellular biomaterials were implanted in osteochondral defects in the knee or ankle joint in healthy animals were included and study characteristics tabulated (283 studies out of 6,688 studies found. For studies comparing non-treated empty defects to defects containing implanted biomaterials and using semi-quantitative histology as outcome measure, the risk of bias (135 studies was assessed and outcome data were collected for meta-analysis (151 studies. Random-effects meta-analyses were performed, using cartilage regeneration as outcome measure on an absolute 0–100% scale. Implantation of acellular

  4. Improved cartilage regeneration by implantation of acellular biomaterials after bone marrow stimulation: a systematic review and meta-analysis of animal studies.

    Science.gov (United States)

    Pot, Michiel W; Gonzales, Veronica K; Buma, Pieter; IntHout, Joanna; van Kuppevelt, Toin H; de Vries, Rob B M; Daamen, Willeke F

    2016-01-01

    Microfracture surgery may be applied to treat cartilage defects. During the procedure the subchondral bone is penetrated, allowing bone marrow-derived mesenchymal stem cells to migrate towards the defect site and form new cartilage tissue. Microfracture surgery generally results in the formation of mechanically inferior fibrocartilage. As a result, this technique offers only temporary clinical improvement. Tissue engineering and regenerative medicine may improve the outcome of microfracture surgery. Filling the subchondral defect with a biomaterial may provide a template for the formation of new hyaline cartilage tissue. In this study, a systematic review and meta-analysis were performed to assess the current evidence for the efficacy of cartilage regeneration in preclinical models using acellular biomaterials implanted after marrow stimulating techniques (microfracturing and subchondral drilling) compared to the natural healing response of defects. The review aims to provide new insights into the most effective biomaterials, to provide an overview of currently existing knowledge, and to identify potential lacunae in current studies to direct future research. A comprehensive search was systematically performed in PubMed and EMBASE (via OvidSP) using search terms related to tissue engineering, cartilage and animals. Primary studies in which acellular biomaterials were implanted in osteochondral defects in the knee or ankle joint in healthy animals were included and study characteristics tabulated (283 studies out of 6,688 studies found). For studies comparing non-treated empty defects to defects containing implanted biomaterials and using semi-quantitative histology as outcome measure, the risk of bias (135 studies) was assessed and outcome data were collected for meta-analysis (151 studies). Random-effects meta-analyses were performed, using cartilage regeneration as outcome measure on an absolute 0-100% scale. Implantation of acellular biomaterials significantly

  5. Multiscale Modeling of Bone

    Science.gov (United States)

    2014-12-01

    is an ordered array of bone fibers in a matrix material [1]. It is the dominant form of bone and closely resembles a layered fiber - reinforced ...mineral [3], [14]. These fibers are not independent structures, but exist only within the complex lamellar bone [13], similar to a fiber reinforced ...accuracy of this method. What this model does not provide is the transverse properties or a Poisson ’ s ratio for TC. Thus, we must assume that

  6. The effect of cartilage and bone density of mushroom-shaped, photooxidized, osteochondral transplants: an experimental study on graft performance in sheep using transplants originating from different species

    Directory of Open Access Journals (Sweden)

    Hilbe Monika

    2005-12-01

    Full Text Available Abstract Background Differences in overall performance of osteochondral photooxidized grafts were studied in accordance of their species origin and a new, more rigorous cleansing procedure using alcohol during preparation. Methods Photooxidized mushroom-shaped grafts of bovine, ovine, human and equine origin were implanted in the femoral condyles of 32 sheep (condyles: n = 64. No viable chondrocytes were present at the time of implantation. Grafts were evaluated at 6 months using plastic embedded sections of non-decalcified bone and cartilage specimens. Graft incorporation, the formation of cyst-like lesions at the base of the cartilage junction as well as cartilage morphology was studied qualitatively, semi-quantitatively using a score system and quantitatively by performing histomorphometrical measurements of percentage of bone and fibrous tissue of the original defects. For statistical analysis a factorial analysis of variance (ANOVA- test was applied. Results Differences of graft performance were found according to species origin and cleansing process during graft preparation. According to the score system cartilage surface integrity was best for equine grafts, as well as dislocation or mechanical stability. The equine grafts showed the highest percentage for bone and lowest for fibrous tissue, resp. cystic lesions. The new, more rigorous cleansing process decreased cartilage persistence and overall graft performance. Conclusion Performance of grafts from equine origin was better compared to bovine, ovine and human grafts. The exact reason for this difference was not proven in the current study, but could be related to differences in density of cartilage and subchondral bone between species.

  7. Extraskeletal and intraskeletal new bone formation induced by demineralized bone matrix combined with bone marrow cells

    International Nuclear Information System (INIS)

    Lindholm, T.S.; Nilsson, O.S.; Lindholm, T.C.

    1982-01-01

    Dilutions of fresh autogenous bone marrow cells in combination with allogeneic demineralized cortical bone matrix were tested extraskeletally in rats using roentgenographic, histologic, and 45 Ca techniques. Suspensions of bone marrow cells (especially diluted 1:2 with culture media) combined with demineralized cortical bone seemed to induce significantly more new bone than did demineralized bone, bone marrow, or composite grafts with whole bone marrow, respectively. In a short-term spinal fusion experiment, demineralized cortical bone combined with fresh bone marrow produced new bone and bridged the interspace between the spinous processes faster than other transplantation procedures. The induction of undifferentiated host cells by demineralized bone matrix is further complemented by addition of autogenous, especially slightly diluted, bone marrow cells

  8. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the body. X-rays are the oldest and most frequently used form of medical imaging. A bone ... bones. top of page How should I prepare? Most bone x-rays require no special preparation. You ...

  9. Exercise for Your Bone Health

    Science.gov (United States)

    ... FAQs Breadcrumb Home Exercise for Your Bone Health Exercise for Your Bone Health Vital at every age ... A Complete Osteoporosis Program For Your Information Why Exercise? Like muscle, bone is living tissue that responds ...

  10. Bone Cancer—Patient Version

    Science.gov (United States)

    Bone cancer is rare and includes several types. Some bone cancers, including osteosarcoma and Ewing sarcoma, are seen most often in children and young adults. Start here to find information on bone cancer treatment, research, and statistics.

  11. Bone-building exercise (image)

    Science.gov (United States)

    Exercise plays an important role in the retention of bone density in the aging person. Studies show that exercises requiring muscles to pull on bones cause the bones to retain and possibly gain density.

  12. Blood and Bone Marrow Transplant?

    Science.gov (United States)

    ... Topics / Blood and Bone Marrow Transplant Blood and Bone Marrow Transplant Also known as Hematopoietic Stem Cell Transplant , Hematopoietic ... person, called a donor, it is an allogeneic transplant. Blood or bone marrow transplants most commonly are used to treat ...

  13. Transient recycling of resected bone to facilitate mandibular reconstruction--a technical note.

    Science.gov (United States)

    Lee, Jing-Wei; Tsai, Shin-Sheng; Kuo, Yao-Lung

    2006-10-01

    Mandibular reconstruction requires considerable sculptural skills. The intriguingly complex configuration of the structure is difficult to reproduce. It is thus