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Sample records for repaired articular surfaces

  1. Transcriptional profiling differences for articular cartilage and repair tissue in equine joint surface lesions

    Directory of Open Access Journals (Sweden)

    Stromberg Arnold J

    2009-09-01

    Full Text Available Abstract Background Full-thickness articular cartilage lesions that reach to the subchondral bone yet are restricted to the chondral compartment usually fill with a fibrocartilage-like repair tissue which is structurally and biomechanically compromised relative to normal articular cartilage. The objective of this study was to evaluate transcriptional differences between chondrocytes of normal articular cartilage and repair tissue cells four months post-microfracture. Methods Bilateral one-cm2 full-thickness defects were made in the articular surface of both distal femurs of four adult horses followed by subchondral microfracture. Four months postoperatively, repair tissue from the lesion site and grossly normal articular cartilage from within the same femorotibial joint were collected. Total RNA was isolated from the tissue samples, linearly amplified, and applied to a 9,413-probe set equine-specific cDNA microarray. Eight paired comparisons matched by limb and horse were made with a dye-swap experimental design with validation by histological analyses and quantitative real-time polymerase chain reaction (RT-qPCR. Results Statistical analyses revealed 3,327 (35.3% differentially expressed probe sets. Expression of biomarkers typically associated with normal articular cartilage and fibrocartilage repair tissue corroborate earlier studies. Other changes in gene expression previously unassociated with cartilage repair were also revealed and validated by RT-qPCR. Conclusion The magnitude of divergence in transcriptional profiles between normal chondrocytes and the cells that populate repair tissue reveal substantial functional differences between these two cell populations. At the four-month postoperative time point, the relative deficiency within repair tissue of gene transcripts which typically define articular cartilage indicate that while cells occupying the lesion might be of mesenchymal origin, they have not recapitulated differentiation to

  2. Contact models of repaired articular surfaces: influence of loading conditions and the superficial tangential zone.

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    Owen, John R; Wayne, Jennifer S

    2011-07-01

    The superficial tangential zone (STZ) plays a significant role in normal articular cartilage's ability to support loads and retain fluids. To date, tissue engineering efforts have not replicated normal STZ function in cartilage repairs. This finite element study examined the STZ's role in normal and repaired articular surfaces under different contact conditions. Contact area and pressure distributions were allowed to change with time, tension-compression nonlinearity modeled collagen behavior in the STZ, and nonlinear geometry was incorporated to accommodate finite deformation. Responses to loading via impermeable and permeable rigid surfaces were compared to loading via normal cartilage, a more physiologic condition, anticipating the two rigid loading surfaces would bracket that of normal. For models loaded by normal cartilage, an STZ placed over the inferior repair region reduced the short-term axial compression of the articular surface by 15%, when compared to a repair without an STZ. Covering the repair with a normal STZ shifted the flow patterns and strain levels back toward that of normal cartilage. Additionally, reductions in von Mises stress (21%) and an increase in fluid pressure (13%) occurred in repair tissue under the STZ. This continues to show that STZ properties of sufficient quality are likely critical for the survival of transplanted constructs in vivo. However, response to loading via normal cartilage did not always fall within ranges predicted by the rigid surfaces. Use of more physiologic contact models is recommended for more accurate investigations into properties critical to the success of repair tissues.

  3. Arthroscopic Repair of Articular Surface Partial-Thickness Rotator Cuff Tears: Transtendon Technique versus Repair after Completion of the Tear—A Meta-Analysis

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    Yohei Ono

    2016-01-01

    Full Text Available Articular surface partial-thickness rotator cuff tears (PTRCTs are commonly repaired using two different surgical techniques: transtendon repair or repair after completion of the tear. Although a number of studies have demonstrated excellent clinical outcomes, it is unclear which technique may provide superior clinical outcomes and tendon healing. The purpose was to evaluate and compare the clinical outcomes following arthroscopic repair of articular surface PTRCT using a transtendon technique or completion of the tear. A systematic review of the literature was performed following PRISMA guidelines and checklist. The objective outcome measures evaluated in this study were the Constant Score, American Shoulder and Elbow Surgeons score, Visual Analogue Scale, physical examination, and complications. Three studies met our criteria. All were prospective randomized comparative studies with level II evidence and published from 2012 to 2013. A total of 182 shoulders (mean age 53.7 years; mean follow-up 40.5 months were analyzed as part of this study. Both procedures provided excellent clinical outcomes with no significant difference in Constant Score and other measures between the procedures. Both procedures demonstrated improved clinical outcomes. However, there were no significant differences between each technique. Further studies are required to determine the long-term outcome of each technique.

  4. Advanced Strategies for Articular Cartilage Defect Repair

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    Fergal J. O'Brien

    2013-02-01

    Full Text Available Articular cartilage is a unique tissue owing to its ability to withstand repetitive compressive stress throughout an individual’s lifetime. However, its major limitation is the inability to heal even the most minor injuries. There still remains an inherent lack of strategies that stimulate hyaline-like articular cartilage growth with appropriate functional properties. Recent scientific advances in tissue engineering have made significant steps towards development of constructs for articular cartilage repair. In particular, research has shown the potential of biomaterial physico-chemical properties significantly influencing the proliferation, differentiation and matrix deposition by progenitor cells. Accordingly, this highlights the potential of using such properties to direct the lineage towards which such cells follow. Moreover, the use of soluble growth factors to enhance the bioactivity and regenerative capacity of biomaterials has recently been adopted by researchers in the field of tissue engineering. In addition, gene therapy is a growing area that has found noteworthy use in tissue engineering partly due to the potential to overcome some drawbacks associated with current growth factor delivery systems. In this context, such advanced strategies in biomaterial science, cell-based and growth factor-based therapies that have been employed in the restoration and repair of damaged articular cartilage will be the focus of this review article.

  5. The Functions of BMP3 in Rabbit Articular Cartilage Repair

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    Zhe Zhang

    2015-10-01

    Full Text Available Bone morphogenetic proteins (BMPs play important roles in skeletal development and repair. Previously, we found fibroblast growth factor 2 (FGF2 induced up-regulation of BMP2, 3, 4 in the process of rabbit articular cartilage repair, which resulted in satisfactory repair effects. As BMP2/4 show a clearly positive effect for cartilage repair, we investigated the functions of BMP3 in rabbit articular cartilage repair. In this paper, we find that BMP3 inhibits the repair of partial-thickness defect of articular cartilage in rabbit by inducing the degradation of extracellular matrix, interfering with the survival of chondrocytes surrounding the defect, and directly inhibiting the expression of BMP2 and BMP4. Meanwhile BMP3 suppress the repair of full-thickness cartilage defect by destroying the subchondral bone through modulating the proliferation and differentiation of bone marrow stem cells (BMSCs, and directly increasing the expression of BMP4. Although BMP3 has different functions in the repair of partial and full-thickness defects of articular cartilage in rabbit, the regulation of BMP expression is involved in both of them. Together with our previous findings, we suggest the regulation of the BMP signaling pathway by BMP3 is essential in articular cartilage repair.

  6. Experimental articular cartilage repair in the Göttingen minipig

    DEFF Research Database (Denmark)

    Christensen, Bjørn Borsøe; Foldager, Casper Bindzus; Olesen, Morten Lykke;

    2015-01-01

    BACKGROUND: A gold standard treatment for articular cartilage injuries is yet to be found, and a cost-effective and predictable large animal model is needed to bridge the gap between in vitro studies and clinical studies. Ideally, the animal model should allow for testing of clinically relevant...... treatments and the biological response should be reproducible and comparable to humans. This allows for a reliable translation of results to clinical studies.This study aimed at verifying the Göttingen minipig as a pre-clinical model for articular cartilage repair by testing existing clinical cartilage...

  7. Repair of articular cartilage defects in minipigs by microfracture surgery and BMSCs transplantation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To investigate the feasibility of minimal invasive repair of cartilage defect by arthroscope-aided microfracture surgery and autologous transplantation of mesenchymal stem cells. Methods: Bone marrow of minipigs was taken out and the bone marrow derived mesenchymal stem cells (BMSCs) were isolated and cultured to passage 3. Then 6 minipigs were randomly divided into 2 groups with 6 knees in each group. After the articular cartilage defect was induced in each knee. the left defect received microfracture surgery and was injected with 2. 5 ml BMSCs cells at a concentration of 3×107 cells/ml into the articular cavity; while right knee got single microfracture or served as blank control group. The animals were killed at 8 or 16 weeks, and the repair tissue was histologically and immunohistochemically examined for the presence of type Ⅱ collagen and glycosaminoglycans (GAGs) at 8 and 16 weeks. Results:Eight weeks after the surgery, the overlying articular surface of the cartilage defect showed normal color and integrated to adjacent cartilage. And 16 weeks after surgery, hyaline cartilage was observed at the repairing tissues and immunostaining indicated the diffuse presence of this type Ⅱ collagen and GAGs throughout the repair cartilage in the treated defects. Single microfracture group had the repairing of fibro-cartilage, while during the treatment, the defects of blank group were covered with fewer fiber tissues, and no blood capillary growth or any immunological rejection was observed. Conclusion:Microfracture technique and BMSCs transplantation to repair cartilage defect is characterized with minimal invasion and easy operation, and it will greatly promote the regeneration repair of articular cartilage defect.

  8. Spectrocolorimetric evaluation of repaired articular cartilage after a microfracture

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    Dohi Yoshihiro

    2008-09-01

    Full Text Available Abstract Background In clinical practice, surgeons differentiate color changes in repaired cartilage compared with surrounding intact cartilage, but cannot quantify these color changes. Objective assessments are required. A spectrocolorimeter was used to evaluate whether intact and repaired cartilage can be quantified. Findings We investigated the use of a spectrocolorimeter and the application of two color models (L* a* b* colorimetric system and spectral reflectance distribution to describe and quantify articular cartilage. In this study, we measured the colors of intact and repaired cartilage after a microfracture. Histologically, the repaired cartilage was a mixture of fibrocartilage and hyaline cartilage. In the L* a* b* colorimetric system, the L* and a* values recovered to close to the values of intact cartilage, whereas the b* value decreased over time after the operation. Regarding the spectral reflectance distribution at 12 weeks after the operation, the repaired cartilage had a higher spectral reflectance ratio than intact cartilage between wavelengths of 400 to 470 nm. Conclusion This study reports the first results regarding the relationship between spectrocolorimetric evaluation and the histological findings of repair cartilage after a microfracture. Our findings demonstrate the ability of spectrocolorimetric measurement to judge the repair cartilage after treatment on the basis of objective data such as the L*, a* and b* values and the SRP as a coincidence index of the spectral reflectance curve.

  9. Articular cartilage repair and the evolving role of regenerative medicine

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    Pieter K Bos

    2010-10-01

    Full Text Available Pieter K Bos1, Marloes L van Melle1, Gerjo JVM van Osch1,21Department of Orthopaedic Surgery, Erasmus MC, Rotterdam, the Netherlands; 2Department of Otorhinolaryngology, Erasmus MC, Rotterdam, the NetherlandsAbstract: Among the growing applications of regenerative medicine, clinical articular cartilage repair has now been used for 2 decades and forms a successful example of translational medicine. Cartilage is characterized by a limited intrinsic repair capacity following injury. Articular cartilage defects cause symptoms, are not spontaneously repaired, and are generally believed to result in early osteoarthritis. Marrow stimulation techniques, osteochondral transplantation, and cell-based therapies, such as autologous chondrocyte implantation (ACI and use of mesenchymal stem cells (MSCs, are used for tissue regeneration, symptom relief, and prevention of further joint degeneration. The exact incidence of cartilage defects and the natural outcome of joints with these lesions are unclear. Currently available cartilage repair techniques are designed for defect treatment in otherwise healthy joints and limbs, mostly in young adults. The natural history studies presented in this review estimated that the prevalence of cartilage lesions in this patient group ranges from 5% to 11%. The background and results from currently available randomized clinical trials of the three mostly used cartilage repair techniques are outlined in this review. Osteochondral transplantation, marrow stimulation, and ACI show improvement of symptoms with an advantage for cell-based techniques, but only a suggestion that risk for joint degeneration can be reduced. MSCs, characterized by their good proliferative capacity and the potential to differentiate into different mesenchymal lineages, form an attractive alternative cell source for cartilage regeneration. Moreover, MSCs provide a regenerative microenvironment by the secretion of bioactive factors. This trophic activity

  10. Effects of low-intensity pulsed ultrasound in repairing injured articular cartilage

    Institute of Scientific and Technical Information of China (English)

    JIA Xiao-lin; CHEN Wen-zhi; ZHOU Kun; WANG Zhi-biao

    2005-01-01

    Objective: To investigate the effects of low-intensity pulsed ultrasound in repairing injured articular cartilage. Methods: Ten adult New Zealand rabbits with bilateral full-thickness osteochondral defects on the cartilage surface of intercondylar fossas were used in this study. The wounds in the left knees were treated with low-intensity pulsed ultrasound as the experimental group. The right knees received no treatment as the control group. All the animals were killed at 8 weeks after injury and the tissues in the wounds were collected for gross appearance grading, histological grading and proteoglycan quantity. Results: The scores of the gross appearance grades, histological grades and the optical density of toluidine blue of the tissues in the experimental group were significantly higher than those of the controls at 8 weeks after injury (P<0.05). Conclusions: Low-intensity pulsed ultrasound can accelerate the repair of injured articular cartilage.

  11. Porous polymers for repair and replacement of the knee joint meniscus and articular cartilage

    NARCIS (Netherlands)

    Klompmaker, Jan

    1992-01-01

    The studies presented here were initiated to answer a variety of questions concerning firstly the repair and replacement of the knee joint meniscus and, secondly, the repair of full-thickness defects of articular cartilage. AIMS OF THE STUDIES I To assess the effect of implantation of a porous polym

  12. Is magnetic resonance imaging reliable in predicting clinical outcome after articular cartilage repair of the knee?

    NARCIS (Netherlands)

    Windt, de T.S.; Welsch, G.H.; Brittberg, M.; Vonk, L.A.; Marlovits, S.; Trattnig, S.; Saris, D.B.F.

    2013-01-01

    Background: While MRI can provide a detailed morphological evaluation after articular cartilage repair, its additional value in determining clinical outcome has yet to be determined. Purpose: To evaluate the correlation between MRI and clinical outcome after cartilage repair and to identify parame

  13. The subchondral bone in articular cartilage repair: current problems in the surgical management

    NARCIS (Netherlands)

    Gomoll, A.H.; Madry, H.; Knutsen, G.; van Dijk, N.; Seil, R.; Brittberg, M.; Kon, E.

    2010-01-01

    As the understanding of interactions between articular cartilage and subchondral bone continues to evolve, increased attention is being directed at treatment options for the entire osteochondral unit, rather than focusing on the articular surface only. It is becoming apparent that without support

  14. Effect of nitric oxide synthase inhibitor on proteoglycan metabolism in repaired articular cartilage in rabbits

    Institute of Scientific and Technical Information of China (English)

    孙炜; 金大地; 王吉兴; 秦立赟; 刘晓霞

    2003-01-01

    Objective: To study the effect of nitric oxide synthase inhibitor, S-methyl thiocarbamate (SMT), on proteoglycan metabolism in repaired articular cartilage in rabbits. Methods: Twenty-four male New Zealand white rabbits, aged 8 months and weighing 2.5 kg±0.2 kg, were used in this study. Cartilage defects in full thickness were created on the intercondylar articular surface of bilateral femurs of all the rabbits. Then the rabbits were randomly divided into 3 groups (n=8 in each group). The defects in one group were filled with fibrin glue impregnated with recombinant human bone morphogenetic protein-2 (rhBMP-2, BMP group), in one group with fibrin glue impregnated with rhBMP-2 and hypodermic injection with SMT (SMT group) and in the other group with nothing (control group). All the animals were killed at one year postoperatively. The tissue sections were stained with safranine O-fast green and analyzed by Quantiment 500 system to determine the content of glycosaminoglycan through measuring the percentage of safranine O-stained area, the thickness of cartilages and the mean gray scale (average stain intensity). Radiolabelled sodium sulphate (Na235SO4) was used to assess the proteoglycan synthesis. Results: At one year postoperatively, the percentage of safranine O-stained area, the mean gray scale and the cartilage thickness of the repaired tissues in SMT group were significantly higher than those of BMP group (P<0.01) and the control group (P<0.05). Result of incorporation of Na235SO4 showed that the proteoglycan synthesis in SMT group was higher than those of BMP group and the control group (P<0.01). Conclusions: SMT, a nitric oxide synthase inhibitor, can significantly increase the content of glycosaminoglycan and proteoglycan synthesis, and computer-based image analysis is a reliable method for evaluating proteoglycan metabolism.

  15. Repairing articular cartilage defects with tissue-engineering cartilage in rabbits

    Institute of Scientific and Technical Information of China (English)

    SONG Hong-xing; LI Fo-bao; SHEN Hui-liang; LIAO Wei-ming; LIU Miao; WANG Min; CAO Jun-ling

    2006-01-01

    Objective: To investigate the effect of cancellous bone matrix gelatin (BMG) engineered with allogeneic chondrocytes in repairing articular cartilage defects in rabbits.Methods: Chondrocytes were seeded onto three-dimensional cancellous BMG and cultured in vitro for 12 days to prepare BMG-chondrocyte complexes. Under anesthesia with 2.5% pentobarbital sodium (1 ml/kg body weight), articular cartilage defects were made on the right knee joints of 38 healthy New Zealand white rabbits (regardless of sex, aged 4-5 months and weighing 2.5-3 kg) and the defects were then treated with 2.5 % trypsin.Then BMG-chondrocyte complex (Group A, n=18 ),BMG ( Group B, n=10), and nothing ( Group C, n=10)were implanted into the cartilage defects, respectively. The repairing effects were assessed by macroscopic, histologic,transmission electron microscopic (TEM) observation,immunohistochemical examination and in situ hybridization detection, respectively, at 2, 4, 8, 12 and 24 weeks after operation.Results: Cancellous BMG was degraded within 8 weeks after operation. In Group A, lymphocyte infiltration was observed around the graft. At 24 weeks after operation, the cartilage defects were repaired by cartilage tissues and the articular cartilage and subchondral bone were soundly healed. Proteoglycan and type Ⅱ collagen were detected in the matrix of the repaired tissues by Safranin-O staining and immunohistochemical staining,respectively. In situ hybridization proved gene expression of type Ⅱ collagen in the cytoplasm of chondrocytes in the repaired tissues. TEM observation showed that chondrocytes and cartilage matrix in repaired tissues were almost same as those in the normal articular cartilage. In Group B, the defects were repaired by cartilage-fibrous tissues. In Group C, the defects were repaired only by fibrous tissues.Conclusions : Cancellous BMG can be regarded as the natural cell scaffolds for cartilage tissue engineering.Articular cartilage defects can be repaired by

  16. Metric analysis of loading magnitudes at articular and non-articular weight-bearing surfaces in human calcaneus.

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    Mahato, Niladri Kumar; Murthy, S Sathiya Narayana

    2013-03-01

    The calcaneus is axially loaded at its articular interface with the talus. A large bulk of this load is transmitted to the ground across the non-articular tubercles at the plantar surface of the bone. A small part of the incumbent load sustained by the calcaneus is directed towards the forefoot at the calcaneo-cuboid junction. This study investigates the proportion of load distributed across the articular and non-articular surfaces of the calcaneus. The present study demonstrates strong and significant correlation between some of the load bearing variables and suggests the need for further investigations to understand the effect of angular aspects of axial loading on the calcaneus. Accounting for the relative distribution of weight across the articular and non-articular areas may enable us to appreciate the internal trabecular structure of the calcaneus in light of its clinical importance.

  17. Biomechanical analysis of articular-sided partial-thickness rotator cuff tear and repair.

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    Mihata, Teruhisa; McGarry, Michelle H; Ishihara, Yoko; Bui, Christopher N H; Alavekios, Damon; Neo, Masashi; Lee, Thay Q

    2015-02-01

    Articular-sided partial-thickness rotator cuff tears are common injuries in throwing athletes. The superior shoulder capsule beneath the supraspinatus and infraspinatus tendons works as a stabilizer of the glenohumeral joint. To assess the effect of articular-sided partial-thickness rotator cuff tear and repair on shoulder biomechanics. The hypothesis was that shoulder laxity might be changed because of superior capsular plication in transtendon repair of articular-sided partial-thickness rotator cuff tears. Controlled laboratory study. Nine fresh-frozen cadaveric shoulders were tested by using a custom shoulder-testing system at the simulated late-cocking phase and acceleration phase of throwing motion. Maximum glenohumeral external rotation angle, anterior translation, position of the humeral head apex with respect to the glenoid, internal impingement area, and glenohumeral and subacromial contact pressures were measured. Each specimen underwent 3 stages of testing: stage 1, with the intact shoulder; stage 2, after creation of articular-sided partial-thickness tears of the supraspinatus and infraspinatus tendons; and stage 3, after transtendon repair of the torn tendons by using 2 suture anchors. Articular-sided partial-thickness tears did not significantly change any of the shoulder biomechanical measurements. In the simulated late-cocking phase, transtendon rotator cuff repair resulted in decreased maximum external rotation angle by 4.2° (P = .03), posterior shift of the humeral head (1.1-mm shift; P = .02), decreased glenohumeral contact pressure by 1.7 MPa (56%; P = .004), and decreased internal impingement area by 26.4 mm(2) (65%; P infraspinatus tears decreased glenohumeral and subacromial contact pressures at time zero; these changes might lead to reduced secondary subacromial and internal impingements and consequently progression to full-thickness rotator cuff tear. However, repair of the tendons decreased anterior translation and external rotation and

  18. Early micromovement of the Articular Surface Replacement (ASR) femoral component

    DEFF Research Database (Denmark)

    Penny, J O; Ding, M; Varmarken, J E;

    2012-01-01

    Radiostereometric analysis (RSA) can detect early micromovement in unstable implant designs which are likely subsequently to have a high failure rate. In 2010, the Articular Surface Replacement (ASR) was withdrawn because of a high failure rate. In 19 ASR femoral components, the mean micromovemen...

  19. Safety of Intra-Articular Use of Atelocollagen for Enhanced Tissue Repair

    OpenAIRE

    Magarian, Elise M; Vavken, Patrick; Connolly, Susan A; Mastrangelo, Ashley N.; Murray, Martha M.

    2012-01-01

    Collagen is an important biomaterial in intra-articular tissue engineering, but there are unanswered questions about its safety. We hypothesize that the addition of type-I-collagen for primary repair of the Anterior Cruciate Ligament (ACL) might result in a local and systemic reaction in a porcine model after 15 weeks as demonstrated by joint effusion, synovial thickening, elevated intraarticular and systemic leukocyte counts. Further, this reaction might be aggravated by the addition of a pl...

  20. Iron oxide labelling of human mesenchymal stem cells in collagen hydrogels for articular cartilage repair.

    Science.gov (United States)

    Heymer, Andrea; Haddad, Daniel; Weber, Meike; Gbureck, Uwe; Jakob, Peter M; Eulert, Jochen; Nöth, Ulrich

    2008-04-01

    For the development of new therapeutical cell-based strategies for articular cartilage repair, a reliable cell monitoring technique is required to track the cells in vivo non-invasively and repeatedly. We present a systematic and detailed study on the performance and biological impact of a simple and efficient labelling protocol for human mesenchymal stem cells (hMSCs). Commercially available very small superparamagnetic iron oxide particles (VSOPs) were used as magnetic resonance (MR) contrast agent. Iron uptake via endocytosis was confirmed histologically with prussian blue staining and quantified by mass spectrometry. Compared with unlabelled cells, VSOP-labelling did neither influence the viability nor the proliferation potential of hMSCs. Furthermore, iron incorporation did not affect hMSCs in undergoing adipogenic, osteogenic or chondrogenic differentiation, as demonstrated histologically and by gene expression analyses. The efficiency of the labelling protocol was assessed with high-resolution MR imaging at 11.7T. VSOP-labelled hMSCs were visualised in a collagen type I hydrogel, which is in clinical use for matrix-based articular cartilage repair. The presence of VSOP-labelled hMSCs was indicated by distinct hypointense spots in the MR images, as a result of iron specific loss of signal intensity. In summary, this labelling technique has great potential to visualise hMSCs and track their migration after transplantation for articular cartilage repair with MR imaging.

  1. Applied anatomy of the medial tibial periosteal flap pedicled with the inferior patellar branch of descending genicular vessels for repair of genicular articular surface%膝降血管髌下支蒂胫骨骨膜瓣移位修复膝关节面的应用解剖

    Institute of Scientific and Technical Information of China (English)

    陈秀清; 陈振光; 喻爱喜; 李国良; 叶勇

    2001-01-01

    Objective:To provide anatomical basis for transposition of the medial tibial periosteal flap pedicled with the inferior patellar branch of the descending genicular vessels for repair of genicular articular surface.Methods:The origins,courses,branches and anastomosis of the inferior patellar of the descending genicular arteries were observed on 30 adult cadavers perfused with red latex.Results:The inferior patellar of the descending genicular arteries desended from the surface of adductor muscle tendon and adductor tubercles and then crossd the surface of the articular capsule at the level of articular space.The inferior patellar branches gave off 2~5 tibial periosteal branches.These branches anastomosed with perosteal branches of the medial inferior genicular arteries and saphenous arteries to supply the superior and middle parts of medial tibial periosteum.Conclusion:The medial tibial periosteal flap pedicled with the inferior patellar branches can be transposed for the treatment of the defect of genicular articular surface.%目的:为用膝降血管髌下支蒂胫骨骨膜瓣移位修复膝关节面病损提供解剖学依据。方法:用30侧经动脉红色乳胶灌注的成人下肢标本,解剖观测膝降动脉髌下支起始、位置、至胫骨内侧面的分支、分布和吻合。结果:膝降动脉髌下支沿大收肌腱板和收肌结节前面下行,至膝关节间隙水平向前横行于关节囊表面,由此向下发2~5支胫骨骨膜支。这些骨膜支与膝下内侧动脉和隐动脉等动脉的胫骨骨膜支相互吻合,分支分布于胫骨内侧面。结论:以膝降血管髌下支为蒂的胫骨骨膜瓣移位可用于治疗膝关节面病损。

  2. Photogrammetric analysis of the articular surface of the distal radius.

    Science.gov (United States)

    Ege, A; Seker, D Z; Tuncay, I; Duran, Z

    2004-01-01

    Three-dimensional measurements made using photogrammetry have recently gained popularity with the development of real-time detection facilities and up-to-date equipment. The modelling of human bones presents a particular challenge as the measurements required are difficult to obtain, especially from uneven surfaces. In this study, the articular surfaces of 12 radius bones were evaluated using photogrammetry to obtain three-dimensional coordinates of certain points. Morphometric characteristics of the digital topography of the articular surface were analysed using three-dimensional data from more than 200 points for each specimen. The coronal plane curve, from the tip of the styloid process to the centre of the distal radioulnar articular notch, was found to be similar to the fourth degree polynomial function. A mathematical expression representing the sagittal curve passing through scapholunate border could not be found. Close-range photogrammetry is a safe and precise technique that can provide reliable, reproducible and accurate data for evaluating complex morphological surfaces.

  3. Spontaneous Redifferentiation of Dedifferentiated Human Articular Chondrocytes on Hydrogel Surfaces

    OpenAIRE

    2010-01-01

    Chondrocytes rapidly dedifferentiate into a more fibroblastic phenotype on a two-dimensional polystyrene substratum. This impedes fundamental research on these cells as well as their clinical application. This study investigated the redifferentiation behavior of dedifferentiated chondrocytes on a hydrogel substratum. Dedifferentiated normal human articular chondrocyte–knee (NHAC-kn) cells were released from the sixth-passage monolayer cultured on a polystyrene surface. These cells were then s...

  4. POSSIBILITIES OF CURRENT CELLULAR TECHNOLOGIES FOR ARTICULAR CARTILAGE REPAIR (ANALYTICAL REVIEW

    Directory of Open Access Journals (Sweden)

    M. S. Bozhokin

    2016-01-01

    Full Text Available Despite a wide variety of surgical procedures utilized in clinical practice for treatment of articular cartilage lesions, the search for other options of articular reconstruction remains a relevant and open issue at the current stage of medicine and biotechnologies development. The recent years demonstrated a strong belief in cellular methods of hyaline cartilage repair such as implantation of autologous chondrocytes (ACI or cultures of mesenchymal stem cells (MSC including techniques for genetic modification of cells.The purpose of presented review is to summarize the published scientific data on up to date results of perspective cellular technologies for articular cartilage repair that are being developed. Autologous chondrocyte transplantation originally performed by Swedish researchers in 1987 is considered the first clinically applied technique for restoration of hyaline cartilage using cellular technologies. However, the transplanted cell culture featured low proliferative capacity and inability to form a regenerate resistant to high physical activity. Another generation of methods originated at the turn of the century utilized mesenchymal stem cells instead of autologous chondrocytes. Preparation of MSCs is a less invasive procedure compared to chondrocytes harvesting and the culture is featured by a higher proliferative ability. Researchers use various biodegradable carriers (matrices to secure cell fixation. Despite good clinical mid-term outcomes the transplanted tissue-engineering structures deteriorate with time due to cellular de-differentiation. Next generation of techniques being currently under pre-clinical studies is featured by the preliminary chondrogenic modification of transplanted cell culture. Usage of various growth factors, modified cell product and gene-activated matrices allow to gain a stable regulatory and key proteins synthesis and achieve a focused influence on regenerate's chondrogenic proliferation and in result

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

    Science.gov (United States)

    Saarakkala, Simo; Laasanen, Mikko S.; Jurvelin, Jukka S.; Töyräs, Juha

    2006-10-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Saarakkala, Simo [Department of Nuclear Medicine, Etelae-Savo Hospital District, Mikkeli Central Hospital, Porrassalmenkatu 35-37, 50100 Mikkeli (Finland); Laasanen, Mikko S [Information Technology R and D Unit, Engineering Kuopio, Savonia Polytechnic, POB 1188, FIN-70211 Kuopio (Finland); Jurvelin, Jukka S [Department of Physics, University of Kuopio, POB 1627, FIN-70211 Kuopio (Finland); Toeyraes, Juha [Department of Clinical Neurophysiology, Kuopio University Hospital and University of Kuopio, POB 1777, FIN-70211 Kuopio (Finland)

    2006-10-21

    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.

  7. Flavonoid Compound Icariin Activates Hypoxia Inducible Factor-1α in Chondrocytes and Promotes Articular Cartilage Repair.

    Directory of Open Access Journals (Sweden)

    Pengzhen Wang

    Full Text Available Articular cartilage has poor capability for repair following trauma or degenerative pathology due to avascular property, low cell density and migratory ability. Discovery of novel therapeutic approaches for articular cartilage repair remains a significant clinical need. Hypoxia is a hallmark for cartilage development and pathology. Hypoxia inducible factor-1alpha (HIF-1α has been identified as a key mediator for chondrocytes to response to fluctuations of oxygen availability during cartilage development or repair. This suggests that HIF-1α may serve as a target for modulating chondrocyte functions. In this study, using phenotypic cellular screen assays, we identify that Icariin, an active flavonoid component from Herba Epimedii, activates HIF-1α expression in chondrocytes. We performed systemic in vitro and in vivo analysis to determine the roles of Icariin in regulation of chondrogenesis. Our results show that Icariin significantly increases hypoxia responsive element luciferase reporter activity, which is accompanied by increased accumulation and nuclear translocation of HIF-1α in murine chondrocytes. The phenotype is associated with inhibiting PHD activity through interaction between Icariin and iron ions. The upregulation of HIF-1α mRNA levels in chondrocytes persists during chondrogenic differentiation for 7 and 14 days. Icariin (10-6 M increases the proliferation of chondrocytes or chondroprogenitors examined by MTT, BrdU incorporation or colony formation assays. Icariin enhances chondrogenic marker expression in a micromass culture including Sox9, collagen type 2 (Col2α1 and aggrecan as determined by real-time PCR and promotes extracellular matrix (ECM synthesis indicated by Alcian blue staining. ELISA assays show dramatically increased production of aggrecan and hydroxyproline in Icariin-treated cultures at day 14 of chondrogenic differentiation as compared with the controls. Meanwhile, the expression of chondrocyte catabolic

  8. Is the repair of articular cartilage lesion by costal chondrocyte transplantation donor age-dependent? An experimental study in rabbits.

    Directory of Open Access Journals (Sweden)

    Janusz Popko

    2006-09-01

    Full Text Available The repair of chondral injuries is a very important problem and a subject of many experimental and clinical studies. Different techniques to induce articular cartilage repair are under investigation. In the present study, we have investigated whether the repair of articular cartilage folowing costal chondrocyte transplantation is donor age-dependent. Transplantation of costal chondrocytes from 4- and 24-week old donors, with artificially induced femoral cartilage lesion, was performed on fourteen 20-week-old New Zealand White male rabbits. In the control group, the lesion was left without chondrocyte transplantation. The evaluation of the cartilage repair was performed after 12 weeks of transplantation. We analyzed the macroscopic and histological appearance of the newly formed tissue. Immunohistochemistry was also performed using monoclonal antibodies against rabbit collagen type II. The newly formed tissue had a hyaline-like appearance in most of the lesions after chondrocyte transplantation. Positive immunohistochemical reaction for collagen II was also observed in both groups with transplanted chondrocytes. Cartilage from adult donors required longer isolation time and induced slightly poorer repair. However, hyaline-like cartilage was observed in most specimens from this group, in contrast to the control group, where fibrous connective tissue filled the lesions. Rabbit costal chondrocytes seem to be a potentially useful material for inducing articular cartilage repair and, even more important, they can also be derived from adult, sexually mature animals.

  9. Ultrasound and Functional Assessment of Transtendinous Repairs of Partial-Thickness Articular-Sided Rotator Cuff Tears.

    Science.gov (United States)

    Ostrander, Roger V; Klauser, Jeffrey M; Menon, Sanjay; Hackel, Joshua G

    2017-03-01

    Partial-thickness articular-sided rotator cuff tears are a frequent source of shoulder pain. Despite conservative measures, some patients continue to be symptomatic and require surgical management. However, there is some controversy as to which surgical approach results in the best outcomes for grade 3 tears. The purpose of this study was to evaluate repair integrity and the clinical results of patients treated with transtendinous repair of high-grade partial-thickness articular-sided rotator cuff tears. Our hypothesis was that transtendinous repairs would result in reliable healing and acceptable functional outcomes. Case series; Level of evidence, 4. Twenty patients with a minimum follow-up of 2 years were included in the study. All patients underwent arthroscopic repair of high-grade partial-thickness rotator cuff tears utilizing a transtendinous technique by a single surgeon. At latest follow-up, the repair integrity was evaluated using ultrasound imaging, and functional scores were calculated. Ultrasound evaluation demonstrated that 18 of 20 patients had complete healing with a normal-appearing rotator cuff. Two patients had a minor residual partial tear. Sixteen of 20 patients had no pain on visual analog scale. Four patients complained of mild intermittent residual pain. All patients were rated as "excellent" by both the University of California at Los Angeles Shoulder Score and the Simple Shoulder Test. The transtendon technique for the repair of articular-sided high-grade partial rotator cuff tears results in reliable tendon healing and excellent functional outcomes.

  10. Tissue engineering for articular cartilage repair – the state of the art

    Directory of Open Access Journals (Sweden)

    B Johnstone

    2013-05-01

    Full Text Available Articular cartilage exhibits little capacity for intrinsic repair, and thus even minor injuries or lesions may lead to progressive damage and osteoarthritic joint degeneration, resulting in significant pain and disability. While there have been numerous attempts to develop tissue-engineered grafts or patches to repair focal chondral and osteochondral defects, there remain significant challenges in the clinical application of cell-based therapies for cartilage repair. This paper reviews the current state of cartilage tissue engineering with respect to different cell sources and their potential genetic modification, biomaterial scaffolds and growth factors, as well as preclinical testing in various animal models. This is not intended as a systematic review, rather an opinion of where the field is moving in light of current literature. While significant advances have been made in recent years, the complexity of this problem suggests that a multidisciplinary approach – combining a clinical perspective with expertise in cell biology, biomechanics, biomaterials science and high-throughput analysis will likely be necessary to address the challenge of developing functional cartilage replacements. With this approach we are more likely to realise the clinical goal of treating both focal defects and even large-scale osteoarthritic degenerative changes in the joint.

  11. Tissue engineering for articular cartilage repair--the state of the art.

    Science.gov (United States)

    Johnstone, Brian; Alini, Mauro; Cucchiarini, Magali; Dodge, George R; Eglin, David; Guilak, Farshid; Madry, Henning; Mata, Alvaro; Mauck, Robert L; Semino, Carlos E; Stoddart, Martin J

    2013-05-02

    Articular cartilage exhibits little capacity for intrinsic repair, and thus even minor injuries or lesions may lead to progressive damage and osteoarthritic joint degeneration, resulting in significant pain and disability. While there have been numerous attempts to develop tissue-engineered grafts or patches to repair focal chondral and osteochondral defects, there remain significant challenges in the clinical application of cell-based therapies for cartilage repair. This paper reviews the current state of cartilage tissue engineering with respect to different cell sources and their potential genetic modification, biomaterial scaffolds and growth factors, as well as preclinical testing in various animal models. This is not intended as a systematic review, rather an opinion of where the field is moving in light of current literature. While significant advances have been made in recent years, the complexity of this problem suggests that a multidisciplinary approach - combining a clinical perspective with expertise in cell biology, biomechanics, biomaterials science and high-throughput analysis will likely be necessary to address the challenge of developing functional cartilage replacements. With this approach we are more likely to realise the clinical goal of treating both focal defects and even large-scale osteoarthritic degenerative changes in the joint.

  12. Repair of articular cartilage in rabbit osteochondral defects promoted by extracorporeal shock wave therapy

    Science.gov (United States)

    Chu, C.-H.; Yen, Y.-S.; Chen, P.-L.; Wen, C.-Y.

    2015-03-01

    This study investigated the stimulative effect of extracorporeal shock wave therapy (ESWT) on the articular cartilage regeneration in the rabbit osteochondral defect model for the first time. An osteochondral defect, 3 mm in diameter and 3 mm in depth, was drilled in the patellar groove at the distal end of each femur in 24 mature New Zealand rabbits. The right patellar defects received 500 impulses of shock waves of (at 14 kV) at 1 week after surgery and were designated as the experimental samples; the left patellar defects served as control. At 4, 8, and 12 weeks after ESWT, cartilage repair was evaluated macroscopically and histologically using a semiquantitative grading scale. The total scores of the macroscopic evaluation at 4, 8, and 12 weeks in the experimental group were superior to those in the control group (statistical significance level ). As to the total scores of the histologic evaluation, the experimental group showed a tendency toward a better recovery than the control group at 4 weeks (). At 8 and 12 weeks the differences between the experimental and control groups became mild and had no significance on statistical analysis. These findings suggested that regeneration of articular cartilage defects might be promoted by ESWT, especially at the early stage. The easy and safe ESWT is potentially viable for clinical application.

  13. Biomechanical comparison of double-row versus transtendon single-row suture anchor technique for repair of the grade Ⅲ partial articular-sided rotator cuff tears

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chun-gang; ZHAO De-wei; WANG Wei-ming; REN Ming-fa; LI Rui-xin; YANG Sheng; LIU Yu-peng

    2010-01-01

    Background For partial-thickness tears of the rotator cuff, double-row fixation and transtendon single-row fixation restore insertion site anatomy, with excellent results. We compared the biomechanical properties of double-row and transtendon single-row suture anchor techniques for repair of grade Ⅲ partial articular-sided rotator cuff tears.Methods In 10 matched pairs of fresh-frozen sheep shoulders, the infraspinatus tendon from 1 shoulder was repaired with a double-row suture anchor technique. This comprised placement of 2 medial anchors with horizontal mattress sutures at an angle of .≤45° into the medial margin of the infraspinatus footprint, just lateral to the articular surface, and 2 lateral anchors with horizontal mattress sutures. Standardized, 50% partial, articular-sided infraspinatus lesions were created in the contralateral shoulder. The infraspinatus tendon from the contralateral shoulder was repaired using two anchors with transtendon single-row mattress sutures. Each specimen underwent cyclic loading from 10 to 100 N for 50 cycles, followed by tensile testing to failure. Gap formation and strain over the footprint area were measured using a motion capture system; stiffness and failure load were determined from testing data.Results Gap formation for the transtendon single-row repair was significantly smaller (P <0.05) when compared with the double-row repair for the first cycle ((1.74±0.38) mm vs. (2.86±0.46) mm, respectively) and the last cycle ((3.77±0.45) mm vs. (5.89±0.61) mm, respectively). The strain over the footprint area for the transtendon single-row repair was significantly smaller (P <0.05) when compared with the double-row repair. Also, it had a higher mean ultimate tensile load and stiffness.Conclusions For grade Ⅲ partial articular-sided rotator cuff tears, transtendon single-row fixation exhibited superior biomechanical properties when compared with double-row fixation.

  14. Topographic matching of distal radius and proximal fibula articular surface for distal radius osteoarticular reconstruction.

    Science.gov (United States)

    Zhang, H; Chen, S; Wang, Z; Guo, Y; Liu, B; Tong, D

    2016-07-01

    During osteoarticular reconstruction of the distal radius with the proximal fibula, congruity between the two articular surfaces is an important factor in determining the quality of the outcome. In this study, a three-dimensional model and a coordinate transformation algorithm were developed on computed tomography scanning. Articular surface matching was performed and parameters for the optimal position were determined quantitatively. The mean radii of best-fit spheres of the articular surfaces of the distal radius and proximal fibula were compared quantitatively. The radial inclination and volar tilt following reconstruction by an ipsilateral fibula graft, rather than the contralateral, best resembles the values of the native distal radius. Additionally, the ipsilateral fibula graft reconstructed a larger proportion of the distal radius articular surface than did the contralateral. The ipsilateral proximal fibula graft provides a better match for the reconstruction of the distal radius articular surface than the contralateral, and the optimal position for graft placement is quantitatively determined.

  15. Inhibitory function of parathyroid hormone-related protein on chondrocyte hypertrophy: the implication for articular cartilage repair.

    Science.gov (United States)

    Zhang, Wei; Chen, Jialin; Zhang, Shufang; Ouyang, Hong Wei

    2012-08-31

    Cartilage repair tissue is usually accompanied by chondrocyte hypertrophy and osseous overgrowths, and a role for parathyroid hormone-related protein (PTHrP) in inhibiting chondrocytes from hypertrophic differentiation during the process of endochondral ossification has been demonstrated. However, application of PTHrP in cartilage repair has not been extensively considered. This review systemically summarizes for the first time the inhibitory function of PTHrP on chondrocyte hypertrophy in articular cartilage and during the process of endochondral ossification, as well as the process of mesenchymal stem cell chondrogenic differentiation. Based on the literature review, the strategy of using PTHrP for articular cartilage repair is suggested, which is instructive for clinical treatment of cartilage injuries as well as osteoarthritis.

  16. Safety of intra-articular use of atelocollagen for enhanced tissue repair.

    Science.gov (United States)

    Magarian, Elise M; Vavken, Patrick; Connolly, Susan A; Mastrangelo, Ashley N; Murray, Martha M

    2012-01-01

    Collagen is an important biomaterial in intra-articular tissue engineering, but there are unanswered questions about its safety. We hypothesize that the addition of type-I-collagen for primary repair of the Anterior Cruciate Ligament (ACL) might result in a local and systemic reaction in a porcine model after 15 weeks as demonstrated by joint effusion, synovial thickening, elevated intraarticular and systemic leukocyte counts. Further, this reaction might be aggravated by the addition of a platelet concentrate. Eighteen porcine ACLs were transected and repaired with either sutures (n=6), a collagen sponge (n=6), or a collagen-platelet-composite (CPC; n=6). Twelve intact contralateral knees served as controls (n=12). No significant synovial thickening or joint effusion was seen in the collagen-treated knees. Synovial fluid leukocyte counts showed no significant differences between surgically treated and intact knees, and no differences were seen in leukocyte counts of the peripheral blood. The addition of a platelet concentrate to the knee joint resulted in lower serum levels of IL-1β, but serum levels of TNF-α were not significantly different between groups. In conclusion, the presence of collagen, with or without added platelets, did not increase the local or systemic inflammatory reactions following surgery, suggesting that Type I collagen is safe to use in the knee joint.

  17. [Systematization of the articular surfaces of the carpometacarpal joints (author's transl)].

    Science.gov (United States)

    el Bacha, A; Maillot, C

    1977-01-01

    A study, done on 100 hands, of the systematization of the articular surfaces of the carpometacarpal joints, clearly delineates the variability of circumference, dimesions, and relief of the articular facets. An attempt to draw general conclusions from this morphological study, in terms of arthrokinetics, leads to an understanding of the nature of the joints and the movements that are performed at this site.

  18. Lubrication mode analysis of articular cartilage using Stribeck surfaces.

    Science.gov (United States)

    Gleghorn, Jason P; Bonassar, Lawrence J

    2008-01-01

    Lubrication of articular cartilage occurs in distinct modes with various structural and biomolecular mechanisms contributing to the low-friction properties of natural joints. In order to elucidate relative contributions of these factors in normal and diseased tissues, determination and control of lubrication mode must occur. The objectives of these studies were (1) to develop an in vitro cartilage on glass test system to measure friction coefficient, mu; (2) to implement and extend a framework for the determination of cartilage lubrication modes; and (3) to determine the effects of synovial fluid on mu and lubrication mode transitions. Patellofemoral groove cartilage was linearly oscillated against glass under varying magnitudes of compressive strain utilizing phosphate buffered saline (PBS) and equine and bovine synovial fluid as lubricants. The time-dependent frictional properties were measured to determine the lubricant type and strain magnitude dependence for the initial friction coefficient (mu(0)=mu(t-->0)) and equilibrium friction coefficient (mu(eq)=mu(t-->infinity)). Parameters including tissue-glass co-planarity, normal strain, and surface speed were altered to determine the effect of the parameters on lubrication mode via a 'Stribeck surface'. Using this testing apparatus, cartilage exhibited biphasic lubrication with significant influence of strain magnitude on mu(0) and minimal influence on mu(eq), consistent with hydrostatic pressurization as reported by others. Lubrication analysis using 'Stribeck surfaces' demonstrated clear regions of boundary and mixed modes, but hydrodynamic or full film lubrication was not observed even at the highest speed (50mm/s) and lowest strain (5%).

  19. Measurements of surface layer of the articular cartilage using microscopic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ryniewicz, A. M; Ryniewicz, W. [Faculty of Mechanical Engineering and Robotics, University of Mining and Metallurgy, A. Mickiewicz Av. 30, 30-059 Cracow (Poland); Ryniewicz, A.; Gaska, A., E-mail: anna@ryniewicz.p, E-mail: andrzej@ryniewicz.p [Laboratory of Coordinate Metrology, Department of Mechanical Engineering, Cracow University of Technology, Jana Pawla II Av. 37, 31-864 Cracow (Poland)

    2010-07-01

    The articular cartilage is the structure that directly cooperates tribologically in biobearing. It belongs to the connective tissues and in the joints it assumes two basic forms: hyaline cartilage that builds joint surfaces and fibrocartilage which may create joint surfaces. From this fibrocartilage are built semilunar cartilage and joint disc are built as well. The research of articular cartilage have been done in macro, micro and nano scale. In all these measurement areas characteristic features occur which can identify biobearing tribology. The aim of the research was the identification of surface layer of articular cartilage by means of scanning electron microscopy (SEM) and atom force microscopy (AFM) and the analysis of topography of these layers. The material used in the research of surface layer was the animal articular cartilage: hyaline cartilage and fibrocartilage.

  20. Repairing sealing surfaces on aluminum castings

    Science.gov (United States)

    Hanna, T. L.

    1980-01-01

    Approach using stylus nickel plating instead of copper and cadmium plating has simplified repair procedure. Damaged sealing surfaces are stylus nickelplated in one step. Superficial scratches and porous areas are removed more easily from repaired surface by simply lapping sealing areas to required finish. Although method is aimed for aerospace components, it may be easily incorporated into conventional aluminumcasting technology. One-step repair can be considered for cast-aluminum automobile and aircraft engines to reduce time and costs.

  1. POROUS POLYMER IMPLANTS FOR REPAIR OF FULL-THICKNESS DEFECTS OF ARTICULAR-CARTILAGE - AN EXPERIMENTAL-STUDY IN RABBIT AND DOG

    NARCIS (Netherlands)

    JANSEN, HWB; VETH, RPH; NIELSEN, HKL; DEGROOT, JH; PENNINGS, AJ

    1992-01-01

    Full-thickness defects of articular cartilage were repaired by implantation of porous polymer implants in rabbits and dogs. The quality of the repair tissue was determined by collagen typing with antibodies. Implants with varying pore sizes and chemical composition were used. The effect of loading

  2. Functional anatomy of the equine temporomandibular joint: Collagen fiber texture of the articular surfaces.

    Science.gov (United States)

    Adams, K; Schulz-Kornas, E; Arzi, B; Failing, K; Vogelsberg, J; Staszyk, C

    2016-11-01

    In the last decade, the equine masticatory apparatus has received much attention. Numerous studies have emphasized the importance of the temporomandibular joint (TMJ) in the functional process of mastication. However, ultrastructural and histological data providing a basis for biomechanical and histopathological considerations are not available. The aim of the present study was to analyze the architecture of the collagen fiber apparatus in the articular surfaces of the equine TMJ to reveal typical morphological features indicating biomechanical adaptions. Therefore, the collagen fiber alignment was visualized using the split-line technique in 16 adult warmblood horses without any history of TMJ disorders. Within the central two-thirds of the articular surfaces of the articular tubercle, the articular disc and the mandibular head, split-lines ran in a correspondent rostrocaudal direction. In the lateral and medial aspects of these articular surfaces, the split-line pattern varied, displaying curved arrangements in the articular disc and punctual split-lines in the bony components. Mediolateral orientated split-lines were found in the rostral and caudal border of the articular disc and in the mandibular fossa. The complex movements during the equine chewing cycle are likely assigned to different areas of the TMJ. The split-line pattern of the equine TMJ is indicative of a relative movement of the joint components in a preferential rostrocaudal direction which is consigned to the central aspects of the TMJ. The lateral and medial aspects of the articular surfaces provide split-line patterns that indicate movements particularly around a dorsoventral axis.

  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. Improving Joint Function Using Photochemical Hydrogels for Articular Surface Repair

    Science.gov (United States)

    2015-10-01

    cells/mL with varying concentrations of tethered TGF-b and 50 nM yielded a maxi - mal response. * indicates statistically significant difference between 50...degradation mechanism [11]. However, natural protein-derived scaffolds are often mechanically weak , and it is difficult to control their

  5. Customized Fabrication of Osteochondral Tissue for Articular Joint Surface Repair

    Science.gov (United States)

    2016-09-01

    Scaffolds for Cartilage Tissue Engineering. Frontiers in Bioengineering and Biotechnology . Nothing to Report Other publications, conference papers...between 20% vs. 25% and 30%. Histological analysis of ECM production using Safranin O/fast green and Alcian Blue /fast red staining is shown in...encapsulated constructs visualized by Alcian blue /fast green staining at day 28. (A-C) Staining of PDLLA-PEG 4000 group. Staining decreases as

  6. Improving Joint Function Using Photochemical Hydrogels for Articular Surface Repair

    Science.gov (United States)

    2014-10-01

    type I collagen (11.4 mg/mL) was obtained from BD Biosciences, Bedford, MA. Ham F12, 10% fetal bovine serum. 1% antibiotic /antimycotic liquid and 1...mixed in an Eppendorf tube with chondrocyte media [Ham F12, 10% fetal bovine serum (Gibco), 1% antibiotic /antimycotic liquid, 1% MEM nones- sential...solution in Ham F-12 medium (Life Sciences, Grand Island, NY) containing 1% Anti-Anti ( antibiotic , antimycotic, Life Sciences) overnight at 37C

  7. Improving Joint Function Using Photochemical Hydrogels for Articular Surface Repair

    Science.gov (United States)

    2017-02-01

    vasculature, cartilage exhibits a low rate of regeneration; hence, focal lesions caused by trauma or joint disorders can lead to debilitating...the dye reagent (Biocolor, Carrickfergus, United Kingdom) containing 1,9-dimethyl-methylene blue, the dissociation reagent (Biocolor) containing the...sodium salt of an anionic surfactant was added to dissociate the sGAG- dye complex and enhance the spectrophotometric absorption profile. The

  8. Improving Joint Function Using Photochemical Hydrogels for Articular Surface Repair

    Science.gov (United States)

    2013-10-01

    solution over 1 hour. The precipitate is then sieved to 300 – 500μm size and sterilized prior to cell seeding [13]. Swine mesenchymal stem cells (MSCs...this system takes advantage of a radical-mediated chemical reaction that selectively bonds thiols to molecules containing carbon - carbon double bonds...often necessitate localized presentation.12Since diffusion of lower molecular weight proteins in hydrogels can be quite rapid, some researchers have

  9. Customized Fabrication of Osteochondral Tissue for Articular Joint Surface Repair

    Science.gov (United States)

    2015-09-01

    company; or  adoption of new practices. What was the impact on society beyond science and technology ? If there is nothing significant to report during...ORGANIZATION REPORT NUMBER University of Pittsburgh, 450 Technology Drive, Pittsburgh, PA, 15219 9. SPONSORING / MONITORING AGENCY NAME(S) AND...it is a disease of the cartilage, bone and surrounding soft tissue that disables 9-10% of the US population. In the US military, combat and non

  10. Quantification of the optical surface reflection and surface roughness of articular cartilage using optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Saarakkala, Simo; Wang Shuzhe; Huang Yanping; Zheng Yongping [Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hong Kong (China)], E-mail: simo.saarakkala@uku.fi, E-mail: ypzheng@ieee.org

    2009-11-21

    Optical coherence tomography (OCT) is a promising new technique for characterizing the structural changes of articular cartilage in osteoarthritis (OA). The calculation of quantitative parameters from the OCT signal is an important step to develop OCT as an effective diagnostic technique. In this study, two novel parameters for the quantification of optical surface reflection and surface roughness from OCT measurements are introduced: optical surface reflection coefficient (ORC), describing the amount of a ratio of the optical reflection from cartilage surface with respect to that from a reference material, and OCT roughness index (ORI) indicating the smoothness of the cartilage surface. The sensitivity of ORC and ORI to detect changes in bovine articular cartilage samples after enzymatic degradations of collagen and proteoglycans using collagenase and trypsin enzymes, respectively, was tested in vitro. A significant decrease (p < 0.001) in ORC as well as a significant increase (p < 0.001) in ORI was observed after collagenase digestion. After trypsin digestion, no significant changes in ORC or ORI were observed. To conclude, the new parameters introduced were demonstrated to be feasible and sensitive to detect typical OA-like degenerative changes in the collagen network. From the clinical point of view, the quantification of OCT measurements is of great interest since OCT probes have been already miniaturized and applied in patient studies during arthroscopy or open knee surgery in vivo. Further studies are still necessary to demonstrate the clinical capability of the introduced parameters for naturally occurring early OA changes in the cartilage.

  11. Quantification of the optical surface reflection and surface roughness of articular cartilage using optical coherence tomography

    Science.gov (United States)

    Saarakkala, Simo; Wang, Shu-Zhe; Huang, Yan-Ping; Zheng, Yong-Ping

    2009-11-01

    Optical coherence tomography (OCT) is a promising new technique for characterizing the structural changes of articular cartilage in osteoarthritis (OA). The calculation of quantitative parameters from the OCT signal is an important step to develop OCT as an effective diagnostic technique. In this study, two novel parameters for the quantification of optical surface reflection and surface roughness from OCT measurements are introduced: optical surface reflection coefficient (ORC), describing the amount of a ratio of the optical reflection from cartilage surface with respect to that from a reference material, and OCT roughness index (ORI) indicating the smoothness of the cartilage surface. The sensitivity of ORC and ORI to detect changes in bovine articular cartilage samples after enzymatic degradations of collagen and proteoglycans using collagenase and trypsin enzymes, respectively, was tested in vitro. A significant decrease (p < 0.001) in ORC as well as a significant increase (p < 0.001) in ORI was observed after collagenase digestion. After trypsin digestion, no significant changes in ORC or ORI were observed. To conclude, the new parameters introduced were demonstrated to be feasible and sensitive to detect typical OA-like degenerative changes in the collagen network. From the clinical point of view, the quantification of OCT measurements is of great interest since OCT probes have been already miniaturized and applied in patient studies during arthroscopy or open knee surgery in vivo. Further studies are still necessary to demonstrate the clinical capability of the introduced parameters for naturally occurring early OA changes in the cartilage.

  12. Articular cartilage repair with recombinant human type II collagen/polylactide scaffold in a preliminary porcine study.

    Science.gov (United States)

    Muhonen, Virpi; Salonius, Eve; Haaparanta, Anne-Marie; Järvinen, Elina; Paatela, Teemu; Meller, Anna; Hannula, Markus; Björkman, Mimmi; Pyhältö, Tuomo; Ellä, Ville; Vasara, Anna; Töyräs, Juha; Kellomäki, Minna; Kiviranta, Ilkka

    2016-05-01

    The purpose of this study was to investigate the potential of a novel recombinant human type II collagen/polylactide scaffold (rhCo-PLA) in the repair of full-thickness cartilage lesions with autologous chondrocyte implantation technique (ACI). The forming repair tissue was compared to spontaneous healing (spontaneous) and repair with a commercial porcine type I/III collagen membrane (pCo). Domestic pigs (4-month-old, n = 20) were randomized into three study groups and a circular full-thickness chondral lesion with a diameter of 8 mm was created in the right medial femoral condyle. After 3 weeks, the chondral lesions were repaired with either rhCo-PLA or pCo together with autologous chondrocytes, or the lesion was only debrided and left untreated for spontaneous repair. The repair tissue was evaluated 4 months after the second operation. Hyaline cartilage formed most frequently in the rhCo-PLA treatment group. Biomechanically, there was a trend that both treatment groups resulted in better repair tissue than spontaneous healing. Adverse subchondral bone reactions developed less frequently in the spontaneous group (40%) and the rhCo-PLA treated group (50%) than in the pCo control group (100%). However, no statistically significant differences were found between the groups. The novel rhCo-PLA biomaterial showed promising results in this proof-of-concept study, but further studies will be needed in order to determine its effectiveness in articular cartilage repair. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:745-753, 2016. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  13. Working conditions of bipolar radiofrequency on human articular cartilage repair following thermal injury during arthroscopy

    Institute of Scientific and Technical Information of China (English)

    Huang Yuelong; Zhang Yujun; Ding Xiaoquan; Liu Songyang; Sun Tiezheng

    2014-01-01

    Background The thermal injury during bipolar radiofrequercy results in chondrocyte death that limits cartilage repair.The purpose was to determine the effects of various factors of bipolar radiofrequency on human articular cartilage after thermal injury,offering suitable working conditions for bipolar radiofrequency during arthroscopy.Methods Osteochondral explants from 28 patients undergoing total knee arthroplasty (TKA) in Department of Orthopaedic,Peking University Reople's Hospital from October 2013 to May 2014,were harvested and treated using bipolar radiofrequency in a light contact mode under the following conditions:various power setting of levels 2,4 and 6; different durations of 2 seconds,5 seconds and 10 seconds; irrigation with fluids of different temperatures of 4℃,22℃,and 37℃; two different bipolar radiofrequency probes ArthroCare TriStar 50 and Paragon T2.The percentage of cell death and depth of cell death were quantified with laser confocal microscopy.The content of proteoglycan elution at different temperatures was determined by spectrophotometer at 530 nm.Results Chondrocyte mortality during the treatment time of 2 seconds and power setting of level 2 was significantly lower than that with long duration or in higher level groups (time:P=0.001; power:P=0.001).The percentage of cell death after thermal injury was gradually reduced by increasing the temperature of the irrigation solutions (P=0.003),the depth of dead chondrocytes in the 37℃ solution group was significantly less than those in the 4℃ and 22℃ groups (P=0.001).The proteoglycan elution was also gradually reduced by increasing the temperature (P=0.004).Compared with the ArthroCare TriStar 50 group,the percentage of cell death in the Paragon T2 group was significantly decreased (P=0.046).Conclusions Thermal chondroplasty with bipolar radiofrequency resulted in defined margins of chondrocyte death under controlled conditions.The least cartilage damage during thermal chondroplasty

  14. Progress in Using Free Autogenous Periosteal Grafts to Repair Articular Cartilage Defects%自体游离骨膜移植修复关节软骨缺损的研究进展

    Institute of Scientific and Technical Information of China (English)

    禹克俊

    2009-01-01

    The cambium layer of Periosteum contains undifferentiated mesenchymal cells, which have the duality into cartilage and into bone. The low tension hypoxia of articular cavity is good for the process, that periosteal becoming to cartilage, but free autologous periosteal graft to repairing articular cartilage defects is still in the exploratory stage, this article is a brief overview on the status quo of autogenous free periosteal graft repairing articular cartilage defects.

  15. Preservation of bursal-sided tendon in partial-thickness articular-sided rotator cuff tears: a novel arthroscopic transtendon anatomic repair technique.

    Science.gov (United States)

    Shin, Sang-Jin; Jeong, Jae-Hoon; Jeon, Yoon Sang; Kim, Rag Gyu

    2016-12-01

    The purpose of this study was to introduce a novel arthroscopic transtendon anatomic repair technique that spares the intact bursal-sided tendon in articular-sided partial-thickness rotator cuff tears (PTRCT) and to present shoulder functional outcomes in patients with symptomatic articular-sided PCRCT that involves more than 50 % of its thickness after arthroscopic repair using a novel technique. Eighteen patients with symptomatic articular-sided PCRCT involving more than 50 % of the tendon's thickness underwent arthroscopic repair using a devised technique. The devised technique restores only the torn articular portion of the rotator cuff at the anatomical footprint using a suture anchor, and preserves the integrity of the corresponding bursal-sided tendon by tying knots at the most lateral bursal side on the subacromial space. Clinical and functional outcome using ASES and Constant scores were evaluated. The structural integrity of the rotator cuff was evaluated by MRI at 6 months postoperatively. Pain relief and shoulder functional outcomes were encouraging during the recovery phase after operation. ASES (preoperative 54.0 ± 10.3 to postoperative 92.6 ± 8.0), Constant score (61.2 ± 8.5-88.0 ± 5.3), VAS for pain (4.9 ± 2.6-0.6 ± 0.7) improved significantly after arthroscopic transtendon anatomic repair (p rotator cuff retears on 6-month MRI. No complications related to surgical procedures had occurred. The devised technique of arthroscopic transtendon repair provided satisfactory functional outcomes without postoperative discomforts. This technique minimizes over-tightening of the articular layer and reduces tension mismatches between the articular and bursal layers, which are considered as important factors for improvement of postoperative shoulder motion.

  16. Plantar pressure analysis after percutaneous repair of displaced intra-articular calcaneal fractures

    NARCIS (Netherlands)

    T. Schepers (Tim); A. van der Stoep (Arjan); H. van der Avert (Hans); E.M.M. van Lieshout (Esther); P. Patka (Peter)

    2008-01-01

    textabstractBackground: Clinical results for the treatment of displaced intra-articular calcaneal fractures are mainly expressed using disease-specific outcome scores, physical examination and radiographs. We hypothesized that plantar pressure and foot position analysis is a valuable tool in

  17. A preclinical evaluation of an autologous living hyaline-like cartilaginous graft for articular cartilage repair: a pilot study.

    Science.gov (United States)

    Peck, Yvonne; He, Pengfei; Chilla, Geetha Soujanya V N; Poh, Chueh Loo; Wang, Dong-An

    2015-11-09

    In this pilot study, an autologous synthetic scaffold-free construct with hyaline quality, termed living hyaline cartilaginous graft (LhCG), was applied for treating cartilage lesions. Implantation of autologous LhCG was done at load-bearing regions of the knees in skeletally mature mini-pigs for 6 months. Over the course of this study, significant radiographical improvement in LhCG treated sites was observed via magnetic resonance imaging. Furthermore, macroscopic repair was effected by LhCG at endpoint. Microscopic inspection revealed that LhCG engraftment restored cartilage thickness, promoted integration with surrounding native cartilage, produced abundant cartilage-specific matrix molecules, and re-established an intact superficial tangential zone. Importantly, the repair efficacy of LhCG was quantitatively shown to be comparable to native, unaffected cartilage in terms of biochemical composition and biomechanical properties. There were no complications related to the donor site of cartilage biopsy. Collectively, these results imply that LhCG engraftment may be a viable approach for articular cartilage repair.

  18. Noninvasive assessment of articular cartilage surface damage using reflected polarized light microscopy.

    Science.gov (United States)

    Huynh, Ruby N; Nehmetallah, George; Raub, Christopher B

    2017-06-01

    Articular surface damage occurs to cartilage during normal aging, osteoarthritis, and in trauma. A noninvasive assessment of cartilage microstructural alterations is useful for studies involving cartilage explants. This study evaluates polarized reflectance microscopy as a tool to assess surface damage to cartilage explants caused by mechanical scraping and enzymatic degradation. Adult bovine articular cartilage explants were scraped, incubated in collagenase, or underwent scrape and collagenase treatments. In an additional experiment, cartilage explants were subject to scrapes at graduated levels of severity. Polarized reflectance parameters were compared with India ink surface staining, features of histological sections, changes in explant wet weight and thickness, and chondrocyte viability. The polarized reflectance signal was sensitive to surface scrape damage and revealed individual scrape features consistent with India ink marks. Following surface treatments, the reflectance contrast parameter was elevated and correlated with image area fraction of India ink. After extensive scraping, polarized reflectance contrast and chondrocyte viability were lower than that from untreated explants. As part of this work, a mathematical model was developed and confirmed the trend in the reflectance signal due to changes in surface scattering and subsurface birefringence. These results demonstrate the effectiveness of polarized reflectance microscopy to sensitively assess surface microstructural alterations in articular cartilage explants.

  19. Functional articular cartilage repair: here, near, or is the best approach not yet clear?

    NARCIS (Netherlands)

    Mastbergen, S.C.; Saris, D.B.F.; Lafeber, F.P.J.G.

    2013-01-01

    In this Review we describe three approaches for cartilage tissue repair at the rheumatology–orthopaedics interface: disease-modifying osteoarthritis (OA) drug (DMOAD) treatment; cell-based therapies, and intrinsic cartilage repair by joint distraction. DMOADs can slow the progression of joint damage

  20. Anatomical study of the ligamentous attachments and articular surfaces of the trapeziometacarpal joint. Consequences on surgical management of its osteoarthrosis.

    Science.gov (United States)

    Maes-Clavier, C; Bellemère, P; Gabrion, A; David, E; Rotari, V; Havet, E

    2014-04-01

    In the goal to optimize conservative surgical techniques of the trapeziometacarpal joint in cases of moderate osteoarthritis, we have defined the relationships between the ligamentous attachments and the articular surfaces onto the trapezium and the first metacarpal bone on the one hand, and the dorsovolar and the transverse diameters of the articular surfaces on the other hand. Thirty-six trapeziometacarpal joints (from 18 fresh cadavers) were studied. They were separated into two groups depending on the macroscopic assessment of chondral disease. Group A included stages I to III (no osteoarthritis or moderate osteoarthritis), group B included stages IV (major cartilage destruction). The dorsovolar and transverse sizes of the articular surfaces were measured. Dorsoradial ligament (DRL), posterior oblique ligament (POL), intermetacarpal ligament (IML), ulnar collateral ligament (UCL) and anterior oblique ligament (AOL) were dissected and the distance between their attachments and the articular surfaces were measured. Group A included 17 joints (71% males) and group B included 19 joints (95% females). For the first metacarpal bone, the average ratio between the dorsovolar diameter and the transverse diameter of metacarpal articular surfaces was significantly higher in group B and the average distance between the ligamentous attachments and the articular surface was more than two millimeters, except for the DRL in group B. For the trapezium, only the posterior ligaments (DRL and POL) of group A were inserted at a mean distance more than two millimeters from the articular surfaces. Dorsovolar length of the metacarpal articular surface was higher for osteoarthritis cases. This difference can be explained by the existence of a palmar osteophyte that was always found in stage IV. Describing a map of the ligamentous attachment distance from the articular surface could help surgeons to avoid the ligamentous injury during minimal osteochondral resection.

  1. In vivo kinematics and articular surface congruency of total ankle arthroplasty during gait.

    Science.gov (United States)

    Yamaguchi, Satoshi; Tanaka, Yasuhito; Banks, Scott; Kosugi, Shinichi; Sasho, Takahisa; Takahashi, Kazuhisa; Takakura, Yoshinori

    2012-08-09

    Relatively high rates of loosening and implant failure have been reported after total ankle arthroplasty. Abnormal kinematics and incongruency of the articular surface may cause increased contact pressure and rotational torque applied to the implant, leading to loosening and implant failure. We measured in vivo kinematics of two-component total ankle arthroplasty (TNK ankle), and assessed congruency of the articular surface during the stance phase of gait. Eighteen ankles of 15 patients with a mean age of 75±6 years (mean±standard deviation) and follow-up of 44±38 months were enrolled. Lateral fluoroscopic images were taken during the stance phase of gait. 3D-2D model-image registration was performed using the fluoroscopic image and the implant models, and three-dimensional kinematics of the implant and incongruency of the articular surface were determined. The mean ranges of motion were 11.1±4.6°, 0.8±0.4°, and 2.6±1.5° for dorsi-/plantarflexion, inversion/eversion, and internal/external rotation, respectively. At least one type of incongruency of the articular surface occurred in eight of 18 ankles, including anterior hinging in one ankle, medial or lateral lift off in four ankles, and excessive axial rotation in five ankles. Among the four ankles in which lift off occurred during gait, only one ankle showed lift off in the static weightbearing radiograph. Our observations will provide useful data against which kinematics of other implant designs, such as three-component total ankle arthroplasty, can be compared. Our results also showed that evaluation of lift off in the standard weightbearing radiograph may not predict its occurrence during gait.

  2. Functional anatomy of the equine temporomandibular joint: Collagen fiber texture of the articular surfaces

    OpenAIRE

    Adams, K.; Schulz-Kornas, E; Arzi, B.; Failing, K.; Vogelsberg, J; Staszyk, C

    2016-01-01

    In the last decade, the equine masticatory apparatus has received much attention. Numerous studies have emphasized the importance of the temporomandibular joint (TMJ) in the functional process of mastication. However, ultrastructural and histological data providing a basis for biomechanical and histopathological considerations are not available. The aim of the present study was to analyze the architecture of the collagen fiber apparatus in the articular surfaces of the equine TMJ to reveal ty...

  3. Green fluorescent protein as marker in chondrocytes overexpressing human insulin-like growth factor-1 for repair of articular cartilage defects in rabbits

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shao-kun; LIU Yi; SONG Zhi-ming; FU Chang-feng; XU Xin-xiang

    2007-01-01

    Objective:To label the primary articular chondrocytes overexpressing human insulin-like growth factor ( hIGF-1 ) with green fluorescent protein (GFP) for repair of articular cartilage defects in rabbits. Methods:GFP cDNA was inserted into pcDNA3.1-hIGF-1 to label the expression vector.The recombinant vector,pcGI,a mammalian expression vector with multiple cloning sites under two respective cytomegalovirus promoters/enhancers,was transfected into the primary articular chondrocytes with the help of lipofectamine.After the positive cell clones were selected by G418,G418-resistant chondrocytes were cultured in medium for 4 weeks.The stable expression of hIGF-1 in the articular chondrocytes was determined by in situ hybridization and immunocytochemical analysis and the GFP was confirmed under a fluorescence microscope. Methyl thiazolyl tetrazolium (MTT) and flow cytometer methods were employed to determine the effect of transfection on proliferation of chondrocytes. Gray value was used to analyze quantitatively the expression of type Ⅱ collagen. Results:The expression of hIGF-1 and GFP was confirmed in transfected chondrocytes by in situ hybridization, immunocytochemical analysis and fluorescence microscope observation. Green articular chondrocytes overexpressing hIGF-1 could expand and maintain their chondrogenic phenotypes for more than 4 weeks.After the transfection of IGF-1,the proliferation of chondrocytes was enhanced and the chondrocytes could effectively maintain the expression of type Ⅱ collagen. Conclusions:The hIGF-1 eukaryotic expression vector containing GFP marker gene has been successfully constructed.GFP,which can be visualized in real time and in situ, is stably expressed in articular chondrocytes overexpressing hIGF-1.The labeled articular chondrocytes overexpressing hIGF-1 can be applied in cell-mediated gene therapy as well as for other biomedical purposes of transgenic chondrocytes.

  4. Repair of full-thickness articular cartilage defects by cultured mesenchymal stem cells transfected with the transforming growth factor {beta}{sub 1} gene

    Energy Technology Data Exchange (ETDEWEB)

    Guo Xiaodong [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Zheng Qixin [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Yang Shuhua [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Shao Zengwu [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Yuan Quan [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Pan Zhengqi [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Tang Shuo [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Liu Kai [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Quan Daping [Institute of Polymer Science, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275 (China)

    2006-12-15

    Articular cartilage repair remains a clinical and scientific challenge with increasing interest focused on the combined techniques of gene transfer and tissue engineering. Transforming growth factor beta 1 (TGF-{beta}{sub 1}) is a multifunctional molecule that plays a central role in promotion of cartilage repair, and inhibition of inflammatory and alloreactive immune response. Cell mediated gene therapy can allow a sustained expression of TGF-{beta}{sub 1} that may circumvent difficulties associated with growth factor delivery. The objective of this study was to investigate whether TGF-{beta}{sub 1} gene modified mesenchymal stem cells (MSCs) could enhance the repair of full-thickness articular cartilage defects in allogeneic rabbits. The pcDNA{sub 3}-TGF-{beta}{sub 1} gene transfected MSCs were seeded onto biodegradable poly-L-lysine coated polylactide (PLA) biomimetic scaffolds in vitro and allografted into full-thickness articular cartilage defects in 18 New Zealand rabbits. The pcDNA{sub 3} gene transfected MSCs/biomimetic scaffold composites and the cell-free scaffolds were taken as control groups I and II, respectively. The follow-up times were 2, 4, 12 and 24 weeks. Macroscopical, histological and ultrastructural studies were performed. In vitro SEM studies found that abundant cartilaginous matrices were generated and completely covered the interconnected pores of the scaffolds two weeks post-seeding in the experimental groups. In vivo, the quality of regenerated tissue improved over time with hyaline cartilage filling the chondral region and a mixture of trabecular and compact bone filling the subchondral region at 24 weeks post-implantation. Joint repair in the experimental groups was better than that of either control group I or II, with respect to: (1) synthesis of hyaline cartilage specific extracellular matrix at the upper portion of the defect; (2) reconstitution of the subchondral bone at the lower portion of the defect and (3) inhibition of

  5. Nanopolymers Delivery of the Bone Morphogenetic Protein-4 Plasmid to Mesenchymal Stem Cells Promotes Articular Cartilage Repair In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Junjun Shi

    2012-01-01

    Full Text Available The clinical application of viral vectors for gene therapy is limited for biosafety consideration. In this study, to promote articular cartilage repair, poly (lactic-co glycolic acid (PLGA nanopolymers were used as non-viral vectors to transfect rabbit mesenchymal stem cells (MSCs with the pDC316-BMP4-EGFP plasmid. The cytotoxicity and transfection efficiency in vitro were acceptable measuring by CCK-8 and flow cytometry. After transfection, Chondrogenic markers (mRNA of Col2a1, Sox9, Bmp4, and Agg of experimental cells (MSCs being transfected with BMP-4 plasmid by PLGA nanopolymers were increased more than those of control cells (MSCs being transfected with naked BMP-4 plasmid alone. In vivo study, twelve rabbits (24 knees with large full thickness articular cartilage defects were randomly divided into the experimental group (MSCs being transfected with BMP-4 plasmid by PLGA nanopolymers and the control group (MSCs being transfected with naked BMP-4 plasmid. The experimental group showed better regeneration than the control group 6 and 12 weeks postoperatively. Hyaline-like cartilage formed at week 12 in the experimental group, indicating the local delivery of BMP-4 plasmid to MSCs by PLGA nanopolymers improved articular cartilage repair significantly. PLGA nanopolymers could be a promising and effective non-viral vector for gene therapy in cartilage repair.

  6. Silk film biomaterials for ocular surface repair

    Science.gov (United States)

    Lawrence, Brian David

    Current biomaterial approaches for repairing the cornea's ocular surface upon injury are partially effective due to inherent material limitations. As a result there is a need to expand the biomaterial options available for use in the eye, which in turn will help to expand new clinical innovations and technology development. The studies illustrated here are a collection of work to further characterize silk film biomaterials for use on the ocular surface. Silk films were produced from regenerated fibroin protein solution derived from the Bombyx mori silkworm cocoon. Methods of silk film processing and production were developed to produce consistent biomaterials for in vitro and in vivo evaluation. A wide range of experiments was undertaken that spanned from in vitro silk film material characterization to in vivo evaluation. It was found that a variety of silk film properties could be controlled through a water-annealing process. Silk films were then generated that could be use in vitro to produce stratified corneal epithelial cell sheets comparable to tissue grown on the clinical standard substrate of amniotic membrane. This understanding was translated to produce a silk film design that enhanced corneal healing in vivo on a rabbit injury model. Further work produced silk films with varying surface topographies that were used as a simplified analog to the corneal basement membrane surface in vitro. These studies demonstrated that silk film surface topography is capable of directing corneal epithelial cell attachment, growth, and migration response. Most notably epithelial tissue development was controllably directed by the presence of the silk surface topography through increasing cell sheet migration efficiency at the individual cellular level. Taken together, the presented findings represent a comprehensive characterization of silk film biomaterials for use in ocular surface reconstruction, and indicate their utility as a potential material choice in the

  7. In vitro three dimensional morphometry of the lateral atlantoaxial articular surfaces.

    Science.gov (United States)

    Cattrysse, Erik; Provyn, Steven; Gagey, Olivier; Kool, Patrick; Clarys, Jan Pieter; Van Roy, Peter

    2008-06-15

    The present study verifies the 3-dimensional anatomic features of the lateral atlantoaxial joints with reference to a local reference frame using a direct in vitro approach. To study the concordance between the axial and atlantal articular surfaces. Detailed information of joint-configurations is imperative for understanding the complex kinematics of the upper cervical joint. Data on the quantitative morphology of the human spinal facet joints has been published, but did not include the atlanto-occipital and atlantoaxial joints. In 20 fresh spine specimens, metal markers were implanted on the cranium, the atlas, and the axis. After registration of the intact specimens, the bony segments were separated and markers and anatomic landmarks were digitized. The size, shape, and orientation relative to the local reference frame of the axis were derived from the relative position data of the joint surface landmarks. The diameters and surface areas of the inferior articular surfaces of the atlas are slightly smaller than the corresponding surfaces on the superior aspects of the axis (17.7 mm and 235 mm vs. 17.0 and 212 mm). In this sample of older-aged specimens, the curvature of the articulating surfaces is nearly flat. The absolute angle between the left and right surface areas is about 130 degrees and corresponds well between axis and atlas. The orientation of the joint surfaces of axis and atlas with respect to the sagittal plane of the axis indicates a good congruency. There seems to be a strong relationship between the anatomic features of the lateral articulating surfaces of atlas and axis. Differences in the orientation of joint surfaces to the frontal plane may be related to deviations from the neutral position. This issue raises the problem of the definition of three-dimensional-neutral joint positions.

  8. Imaging of articular cartilage

    Directory of Open Access Journals (Sweden)

    Bhawan K Paunipagar

    2014-01-01

    Full Text Available We tried to review the role of magnetic resonance imaging (MRI in understanding microscopic and morphologic structure of the articular cartilage. The optimal protocols and available spin-echo sequences in present day practice are reviewed in context of common pathologies of articular cartilage. The future trends of articular cartilage imaging have been discussed with their appropriateness. In diarthrodial joints of the body, articular cartilage is functionally very important. It is frequently exposed to trauma, degeneration, and repetitive wear and tear. MRI has played a vital role in evaluation of articular cartilage. With the availability of advanced repair surgeries for cartilage lesions, there has been an increased demand for improved cartilage imaging techniques. Recent advances in imaging strategies for native and postoperative articular cartilage open up an entirely new approach in management of cartilage-related pathologies.

  9. Cell-based tissue engineering strategies used in the clinical repair of articular cartilage

    Science.gov (United States)

    Huang, Brian J.; Hu, Jerry C.; Athanasiou, Kyriacos A.

    2016-01-01

    One of the most important issues facing cartilage tissue engineering is the inability to move technologies into the clinic. Despite the multitude of review articles on the paradigm of biomaterials, signals, and cells, it is reported that 90% of new drugs that advance past animal studies fail clinical trials (1). The intent of this review is to provide readers with an understanding of the scientific details of tissue engineered cartilage products that have demonstrated a certain level of efficacy in humans, so that newer technologies may be developed upon this foundation. Compared to existing treatments, such as microfracture or autologous chondrocyte implantation, a tissue engineered product can potentially provide more consistent clinical results in forming hyaline repair tissue and in filling the entirety of the defect. The various tissue engineering strategies (e.g., cell expansion, scaffold material, media formulations, biomimetic stimuli, etc.) used in forming these products, as collected from published literature, company websites, and relevant patents, are critically discussed. The authors note that many details about these products remain proprietary, not all information is made public, and that advancements to the products are continuously made. Nevertheless, by fully understanding the design and production processes of these emerging technologies, one can gain tremendous insight into how to best use them and also how to design the next generation of tissue engineered cartilage products. PMID:27177218

  10. Guidelines for the Design and Conduct of Clinical Studies in Knee Articular Cartilage Repair: International Cartilage Repair Society Recommendations Based on Current Scientific Evidence and Standards of Clinical Care.

    Science.gov (United States)

    Mithoefer, Kai; Saris, Daniel B F; Farr, Jack; Kon, Elizaveta; Zaslav, Kenneth; Cole, Brian J; Ranstam, Jonas; Yao, Jian; Shive, Matthew; Levine, David; Dalemans, Wilfried; Brittberg, Mats

    2011-04-01

    To summarize current clinical research practice and develop methodological standards for objective scientific evaluation of knee cartilage repair procedures and products. A comprehensive literature review was performed of high-level original studies providing information relevant for the design of clinical studies on articular cartilage repair in the knee. Analysis of cartilage repair publications and synopses of ongoing trials were used to identify important criteria for the design, reporting, and interpretation of studies in this field. Current literature reflects the methodological limitations of the scientific evidence available for articular cartilage repair. However, clinical trial databases of ongoing trials document a trend suggesting improved study designs and clinical evaluation methodology. Based on the current scientific information and standards of clinical care, detailed methodological recommendations were developed for the statistical study design, patient recruitment, control group considerations, study endpoint definition, documentation of results, use of validated patient-reported outcome instruments, and inclusion and exclusion criteria for the design and conduct of scientifically sound cartilage repair study protocols. A consensus statement among the International Cartilage Repair Society (ICRS) and contributing authors experienced in clinical trial design and implementation was achieved. High-quality clinical research methodology is critical for the optimal evaluation of current and new cartilage repair technologies. In addition to generally applicable principles for orthopedic study design, specific criteria and considerations apply to cartilage repair studies. Systematic application of these criteria and considerations can facilitate study designs that are scientifically rigorous, ethical, practical, and appropriate for the question(s) being addressed in any given cartilage repair research project.

  11. Connective tissue growth factor and articular cartilage repair%结缔组织生长因子与关节软骨的修复

    Institute of Scientific and Technical Information of China (English)

    张世松; 张志峰; 黄健

    2015-01-01

    BACKGROUND:Connective tissue growth factor has the potential to stimulate the differentiation of mesenchymal cels into chondrocytes, can promote the proliferation and differentiation of chondrocytes, and also can promote the expression of type II colagen and proteoglycan in the articular cartilage. So, the connective tissue growth factor plays an important role in the articular cartilage repair along with other growth factors. OBJECTIVE: To focus on the structure of connective tissue growth factor, its function in articular cartilage repair and the interactions with other factors. METHODS: A search across the databases of PubMed (January 1980 to July 2014) was performed, with the key words of “connective tissue growth factor, connective tissue growth factor and articular cartilage, articular cartilage damage, articular cartilage repairment” in English and “articular cartilage injury” in Chinese. Studies with the obsolete, repetitive or unrelated content were excluded. A total of 32 papers were included in thi study. RESULTS AND CONCLUSION: Connective tissue growth factor has the potential to stimulate the differentiation of mesenchymal cels into chondrocytes, can promote the proliferation, differentiation and maturity of chondrocytes, can maintain the extracelular matrix synthesis and balance, and also can promote the expression of type II colagen and proteoglycan in the articular cartilage. Along with other growth factors, connective tissue growth factor exerts an important role in the articular cartilage repair. Connective tissue growth factor is the key factor of chondrocyte growth, proliferation and differentiation, which is throughout the process of cartilage repair. Studies have shown that articular chondrocytes from patients with osteoarthritis show an increase in the number positively correlated with the expressions of fibroblast growth factor 1 and connective tissue growth factor. Connective tissue growth factor interacts with articular cartilage

  12. Return to Sport After Articular Cartilage Repair in Athletes' Knees: A Systematic Review.

    Science.gov (United States)

    Campbell, Andrew B; Pineda, Miguel; Harris, Joshua D; Flanigan, David C

    2016-04-01

    To perform a systematic review of cartilage repair in athletes' knees to (1) determine which (if any) of the most commonly implemented surgical techniques help athletes return to competition, (2) identify which patient- or defect-specific characteristics significantly affect return to sport, and (3) evaluate the methodologic quality of available literature. A systematic review of multiple databases was performed. Return to preinjury level of sport was defined as the ability to play in the same or greater level (i.e., league or division) of competition after surgery. Study methodologic quality for all studies analyzed in this review was evaluated with the Coleman Methodology Score. Systematic review of 1,278 abstracts identified 20 level I-IV studies for inclusion but only 1 randomized controlled trial. Twenty studies (1,117 subjects) were included. Subjects (n = 970) underwent 1 of 4 surgeries (microfracture [n = 529], autologous chondrocyte implantation [ACI, n = 259], osteochondral autograft [n = 139], or osteochondral allograft [n = 43]), and 147 were control patients. The rate of return to sports was greatest after osteochondral autograft transplantation (89%) followed by osteochondral allograft, ACI, and microfracture (88%, 84%, and 75%, respectively). Osteochondral autograft transplantation and ACI had statistically significantly greater rates of return to sports compared with microfracture (P sports participation after microfracture, ACI, osteochondral autograft, or osteochondral allograft, but microfracture patients were least likely to return to sports. The athletes who had a better prognosis after surgery were younger, had a shorter preoperative duration of symptoms, underwent no previous surgical interventions, participated in a more rigorous rehabilitation protocol, and had smaller cartilage defects. Level IV, systematic review of Level I-IV studies. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights

  13. Repair versus shaving of partial-thickness articular-sided tears of the upper subscapularis tendon. A prospective randomized controlled trial

    Science.gov (United States)

    RANDELLI, PIETRO; ARRIGONI, PAOLO; ALIPRANDI, ALBERTO; SDAO, SILVANA; RAGONE, VINCENZA; D’AMBROSI, RICCARDO; RANDELLI, FILIPPO; CABITZA, PAOLO; BANFI, GIUSEPPE

    2015-01-01

    Purpose the purpose of this study was to evaluate whether treating partial-thickness articular-sided tears of the upper subscapularis (SSC) tendon with a dedicated suture anchor would result in an internal rotation strength improvement compared with simple shaving of the SSC tendon and footprint. Methods twenty-six patients with a limited SSC tendon tear (equal or inferior to the most superior centimeter) in association with a posterosuperior cuff lesion were prospectively randomized to two treatments: repair with a dedicated suture anchor versus shaving of the tendon and footprint. The patients also underwent long head of the biceps (LHB) treatment and posterosuperior cuff tear repair. In each patient the following parameters were measured both preoperatively and at a minimum follow-up of 2.5 years: strength in internal rotation in the bear-hug testing position (using a digital tensiometer), DASH score and Constant scores. MRI assessment of tendon healing was performed at the final follow-up. Results twenty of the 26 patients (76%) were reviewed after a mean follow-up time of 42 months: 11 patients had undergone SSC tendon repair and nine simple shaving. At final follow-up no significant differences were found between the repaired and shaving group in strength in internal rotation (9.5 ± 3.8 kg versus 10.3±5.4 kg; p=0.7). The DASH score and Constant score also failed to show significant differences between the two groups. Furthermore, no significant difference in SSC tendon healing rate was observed on MRI evaluation. Conclusions partial-thickness articular-sided tear of the upper SSC tendon in association with a posterosuperior rotator cuff repair and LHB treatment, when limited to the superior centimeter of the SSC tendon, shows a comparable performance in terms of strength in internal rotation either after simple shaving or a tendon-to-bone repair. Level of evidence Level II, prospective comparative study. PMID:26889466

  14. The promotion of osteochondral repair by combined intra-articular injection of parathyroid hormone-related protein and implantation of a bi-layer collagen-silk scaffold.

    Science.gov (United States)

    Zhang, Wei; Chen, Jialin; Tao, Jiadong; Hu, Changchang; Chen, Longkun; Zhao, Hongshi; Xu, Guowei; Heng, Boon C; Ouyang, Hong Wei

    2013-08-01

    The repair of osteochondral defects can be enhanced with scaffolds but is often accompanied with undesirable terminal differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Parathyroid hormone-related protein (PTHrP) has been shown to inhibit aberrant differentiation, but administration at inappropriate time points would have adverse effects on chondrogenesis. This study aims to develop an effective tissue engineering strategy by combining PTHrP and collagen-silk scaffold for osteochondral defect repair. The underlying mechanisms of the synergistic effect of combining PTHrP administration with collagen-silk scaffold implantation for rabbit knee joint osteochondral defect repair were investigated. In vitro studies showed that PTHrP treatment significantly reduced Alizarin Red staining and expression of terminal differentiation-related markers. This is achieved in part through blocking activation of the canonical Wnt/β-catenin signaling pathway. For the in vivo repair study, intra-articular injection of PTHrP was carried out at three different time windows (4-6, 7-9 and 10-12 weeks) together with implantation of a bi-layer collagen-silk scaffold. Defects treated with PTHrP at the 4-6 weeks time window exhibited better regeneration (reconstitution of cartilage and subchondral bone) with minimal terminal differentiation (hypertrophy, ossification and matrix degradation), as well as enhanced chondrogenesis (cell shape, Col2 and GAG accumulation) compared with treatment at other time windows. Furthermore, the timing of PTHrP administration also influenced PTHrP receptor expression, thus affecting the treatment outcome. Our results demonstrated that intra-articular injection of PTHrP at 4-6 weeks post-injury together with collagen-silk scaffold implantation is an effective strategy for inhibiting terminal differentiation and enhancing chondrogenesis, thus improving cartilage repair and regeneration in a rabbit model. Copyright © 2013 Elsevier Ltd. All

  15. Specification guidelines for surface preparation of concrete prior to repair

    OpenAIRE

    Courard, Luc; Bissonnette, Benoît; Garbacz, Andrzej

    2017-01-01

    The repair of concrete requests specific preparation operations needed for guaranteeing compatibility between substrate and new materials as well as the development of adhesion properties. These specification guidelines contain design and construction recommendations for surface preparation of concrete for repair and overlay. The paper summarizes current knowledge, best practices and results of the research concerning the surface preparation of concrete prior to application of repair/overlay ...

  16. INJURED ARTICULAR CARTILAGE REPAIR

    Directory of Open Access Journals (Sweden)

    Ariana Barlič

    2008-02-01

    Surveys show that the most frequently used surgical methods are mosaicplasty and bonemarrow stimulation with microfracturing. The efficacy of the autologous chondrocyte implantationmethod should be superior to microfracturing on a long run. Especially when(regeneration of the hyaline cartilage instead of fibrous tissue (fibrocartilage is concerned.However, it has not been scientifically proved yet

  17. Fibroblast growth factor-2 promotes the repair of partial thickness defects of articular cartilage in immature rabbits but not in mature rabbits.

    Science.gov (United States)

    Yamamoto, Tetsuya; Wakitani, Shigeyuki; Imoto, Kazuhiko; Hattori, Takako; Nakaya, Hiroyuki; Saito, Masanobu; Yonenobu, Kazuo

    2004-08-01

    To investigate cartilage response to fibroblast growth factor-2 (FGF-2) with increasing age in vivo, we examined the effect of FGF-2 on partial thickness defects of immature and mature rabbits. Sixty-nine Japanese white rabbits (34 immature rabbits, 35 mature rabbits) were examined. We made experimental partial thickness defects in articular cartilage of the knees. Then, we injected FGF-2 into the knees eight times, immediately after surgery and every 2 days for 2 weeks. A single dose of FGF-2 was 10 ng/0.1 ml or 100 ng/0.1 ml. In the control group, 0.1 ml saline was injected on the same time schedule. The rabbits were sacrificed at intervals following surgery that ranged from 2 to 48 weeks. The specimens were stained with toluidine blue and examined microscopically. We used a modified semiquantitative scale for evaluating the histological appearance of repair. In immature rabbits, the cartilage repair in the FGF-2 (100 ng)-treated group was significantly better than that of the other groups. The defects were almost completely repaired with chondrocytes that showed a round to polygonal morphology, and large amounts of extracellular matrix with intense metachromatic staining. In mature rabbits, however, there was apparently no effect from FGF-2 in either group. Application of FGF-2 facilitated cartilage repair in partial thickness defects in immature rabbits, but not in mature ones.

  18. Ⅱ型胶原海绵填充材料修复兔关节软骨缺损%Repair of articular cartilage defect in rabbit with type Ⅱ collagen sponge filling material

    Institute of Scientific and Technical Information of China (English)

    贺敬义; 龙瑞芳

    2005-01-01

    of cartilage have been used previously; however, the source of the donor is limited, the fixation is difficult as well as the occurrence of endochondrial ossification and delamination between the inferior cartilage and reparative cartilage, etc. Type Ⅱ collagen, the main component of cartilage matrix, has certain effects in the repair of articular cartilage defect.OBJECTIVE: To investigate the effects of type Ⅱ collagen sponge filling on the repair of articular cartilage defect.DESIGN: A randomized controlled trial.SETTING and MATERIALS: The study was conducted in the Guangzhou Institute of Traumatic Surgery. Materials were 24 adult male purebred New Zealand Rabbits(48 knees), ordinary grade, with a body mass of (2.29 ±0. 25) kg. Animals were fed with standard feeding in separate cage.INTERVENTIONS: A full-thickness defect in articular cartilage was made on the femoral trochlear surface by a drill of 5 mm in diameter and 3 mm in depth. Rabbits were allocated into filling group(type Ⅱ collagen sponge was grafted into left keen joint defect) and control group(right knee joint defect site was set as control) according to random number table.MAIN OUTCOME MEASURES: Gross morphological and histological observation of the defect repair in each dual week within 12 weeks after operation.RESULTS: During 10 - 12 weeks, in cuntrol group: The defect area was repaired by white and soft tissue that had no resistance to press. The repaired tissue was still lower than the surrounding articular surface with clear boundary. By histological observation, it was found that the defect was repaired by the mechanism similar to inflammatory reaction and the defect is ultimately filled by the hyperplasia of hyaline degenerative fibrous tissues. In filling group: the defect was repaired by semi-transparent, smooth, textured tissues with polish that had resistance to press as well as elasticity. The repaired tissue was almost similar to the shape of the surrounding cartilage,difficult to

  19. Allogeneic Bone Marrow Transplant from MRL/MpJ Super-Healer Mice Does Not Improve Articular Cartilage Repair in the C57Bl/6 Strain.

    Directory of Open Access Journals (Sweden)

    Catherine A Leonard

    Full Text Available Articular cartilage has been the focus of multiple strategies to improve its regenerative/ repair capacity. The Murphy Roths Large (MRL/MpJ "super-healer" mouse demonstrates an unusual enhanced regenerative capacity in many tissues and provides an opportunity to further study endogenous cartilage repair. The objective of this study was to test whether the super-healer phenotype could be transferred from MRL/MpJ to non-healer C57Bl/6 mice by allogeneic bone marrow transplant.The healing of 2mm ear punches and full thickness cartilage defects was measured 4 and 8 weeks after injury in control C57Bl/6 and MRL/MpJ "super-healer" mice, and in radiation chimeras reconstituted with bone marrow from the other mouse strain. Healing was assessed using ear hole diameter measurement, a 14 point histological scoring scale for the cartilage defect and an adapted version of the Osteoarthritis Research Society International scale for assessment of osteoarthritis in mouse knee joints.Normal and chimeric MRL mice showed significantly better healing of articular cartilage and ear wounds along with less severe signs of osteoarthritis after cartilage injury than the control strain. Contrary to our hypothesis, however, bone marrow transplant from MRL mice did not confer improved healing on the C57Bl/6 chimeras, either in regards to ear wound healing or cartilage repair.The elusive cellular basis for the MRL regenerative phenotype still requires additional study and may possibly be dependent on additional cell types external to the bone marrow.

  20. Nanoscale Surface Modifications of Medical Implants for Cartilage Tissue Repair and Regeneration

    Science.gov (United States)

    Griffin, MF; Szarko, M; Seifailan, A; Butler, PE

    2016-01-01

    Background: Natural cartilage regeneration is limited after trauma or degenerative processes. Due to the clinical challenge of reconstruction of articular cartilage, research into developing biomaterials to support cartilage regeneration have evolved. The structural architecture of composition of the cartilage extracellular matrix (ECM) is vital in guiding cell adhesion, migration and formation of cartilage. Current technologies have tried to mimic the cell’s nanoscale microenvironment to improve implants to improve cartilage tissue repair. Methods: This review evaluates nanoscale techniques used to modify the implant surface for cartilage regeneration. Results: The surface of biomaterial is a vital parameter to guide cell adhesion and consequently allow for the formation of ECM and allow for tissue repair. By providing nanosized cues on the surface in the form of a nanotopography or nanosized molecules, allows for better control of cell behaviour and regeneration of cartilage. Chemical, physical and lithography techniques have all been explored for modifying the nanoscale surface of implants to promote chondrocyte adhesion and ECM formation. Conclusion: Future studies are needed to further establish the optimal nanoscale modification of implants for cartilage tissue regeneration. PMID:28217208

  1. A novel surface modification on calcium polyphosphate scaffold for articular cartilage tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Lien, S.-M. [Department of Chemical Engineering, National Tsing Hua University, Hsinchu 300 (China); Liu, C.-K. [Department of Chemical Engineering, National Tsing Hua University, Hsinchu 300 (China); Huang, T.-J. [Department of Chemical Engineering, National Tsing Hua University, Hsinchu 300 (China)]. E-mail: tjhuang@che.nthu.edu.tw

    2007-01-15

    The surface of porous three-dimensional (3D) calcium polyphosphate (CPP) scaffold was modified by treatment of quenching-after-sintering in the fabrication process. Scanning electron microscopic examination and degradation tests confirmed a new type of surface modification. A rotary-shaking culture was compared to that of a stationary culture and the results showed that rotary shaking led to enhanced extracellular matrices (ECM) secretion of both proteoglycans and collagen. Rotary-shaking cultured results showed that the quenching-treated CPP scaffold produced a better cartilage tissue, with both proteoglycans and collagen secretions enhanced, than the air-cooled-after-sintering scaffolds. Moreover, {beta}-CPP scaffolds were better for the ECM secretion of both proteoglycans and collagen than the {beta}-CPP + {gamma}-CPP multiphase scaffold. However, the multiphase scaffold led to higher growth rate than that of {beta}-CPP scaffold; the quenching-after-sintering treatment reversed this. In addition, the ECM secretions of both proteoglycans and collagen in the quenching-treated {beta}-CPP scaffold were higher than those in the air-cooled one. Thus, the novel treatment of quenching-after-sintering has shown merits to the porous 3D CPP scaffolds for articular cartilage tissue engineering.

  2. Effect of chemical surface treatments and repair material on transverse strength of repaired acrylic denture resin

    Directory of Open Access Journals (Sweden)

    Vojdani Mahroo

    2008-01-01

    Full Text Available Purpose: This study was performed to evaluate the transverse strength of a denture base resin (H, repaired with an autopolymerizing acrylic resin (A or a visible light-curing (VLC resin (T following the use of three chemical solvents: methyl methacrylate monomer, aceton or chloroform. Materials and Methods: Eighty specimens (65.0 x 10.0 x 3.3 mm of H were fabricated and stored in distilled water at 37°C for seven days. Specimens were divided into eight equal groups of 10. In each group, specimens were sectioned in the middle to create a 10 mm gap. Two groups served as controls and had no surface treatment. They were repaired with A or T materials. In the remaining six experimental groups, specimen surfaces were treated with ac for 30 sec or mma for 180 sec or ch for 5 sec. Then A or T material was placed on the treated surfaces, using the same preparation molds. After seven days′ storage at 37°C, the transverse bond strength (MPa of the specimens was measured using a three-point bending test. A two-way ANOVA and a Tukey HSD were performed to identify significant differences ( P < 0.05. The nature of the failures was noted as adhesive, cohesive or mixed. Results: Significant differences were found between the controls and experimental groups ( P < 0.05. In the control groups, repair with A showed significantly higher strength (60.3 MPa than those repaired with T (51.3 MPa. Mean transverse strength of experimental specimens repaired with A was (75.06 MPa which was significantly greater than those repaired with T (67.9 MPa. Although surface treatment increased repair strength, no significant differences were detected between the effects of the chemical etchants. Conclusions: The autopolymerizing resin exhibited significantly higher repair strength than VLC resin. The transverse strength of the repaired specimens was increased significantly after chemical treatments.

  3. Effect of surface roughness on amalgam repair using adhesive systems.

    Science.gov (United States)

    Giannini, Marcelo; Paulillo, Luis Alexandre Maffei Sartini; Ambrosano, Gláucia Maria Bovi

    2002-01-01

    The objective of this in vitro study was to evaluate the effect of three surface treatments and two adhesive systems on the shear bond strength of old and freshly placed amalgam. The results suggested that the intact amalgam showed a significantly higher strength than repaired groups and the strongest repaired specimens were made when the amalgam surfaces were roughened with a diamond bur or microetcher. The adhesive systems showed no significant differences on bond strength with the same superficial texture.

  4. Biomechanical research of joint III. An experimental biomechanical research on the Femur's articular surface of knee of pongidae

    Science.gov (United States)

    Renxiang, Zhang; Zuyun, Lan; Wenji, Qu

    1986-06-01

    In this paper, moiré contour fringes is applied to study the femur's articular surface of the knee of Pongidae. The preliminary division of the femur's articular surface of knee into three types is proposed. The moiré contour fringes ofthe medial condyle is taken as a mark according to the references. Owing to the fact that the moiré contour fringes obtained from experiments after the 2nd order of fringe basically follow a certain rule, an investigation is made on the distribution of the angle α which is defined as the angle of the major axis of the 2nd order's near-oval shaped moiré contour fringe on the medial condyle with the horizontal axis. Preliminary distribution graphs are given in the paper.

  5. The articular surface replacement implant recall: a United Kingdom district hospital experience.

    Science.gov (United States)

    Whitwell, George S; Shine, Ashokan; Young, Steve K

    2012-01-01

    We present our experience of the articular surface replacement (ASR) hip and the implant recall process. One hundred and twenty-one ASR components were implanted (21 resurfacing hip arthroplasty (RHA) and 100 ASR/XL modular total hip replacements). At the time of the implant recall in August 2010 there were 111 surviving hips (92%) with a mean follow-up of 44 months. Nine hips had been revised and one had been listed for revision surgery. Ninety-two percent of surviving implants were reviewed in the recall clinics, and blood metal ion levels or ultrasound scans were indicated in 38 hips (34%). Immediately after the recall process seven hips (6 ASR/XL and 1 RHA) were listed for revision and a further 9 were kept under close surveillance. One year after completion of the recall process 23 hips (19 ASR/XL and 4 RHA's) had been revised. A diagnosis of adverse reaction to metal debris (ARMD) was made at surgery in all but two hips. Our current revision rate for ASR RHA is 19% (mean follow-up 62 months, range 29-80) and for the ASR/XL is 19% (mean follow-up 53 months, range 10-80). The 5-year cumulative survival rates with revision for any reason for the ASR/XL, was 80.8% (95% confidence interval 72.0 - 89.5). Given experience elsewhere we expect this rate may increase significantly with time.

  6. Problems in laser repair welding of polished surfaces

    Directory of Open Access Journals (Sweden)

    A. Skumavc

    2014-10-01

    Full Text Available This paper presents problems in laser repair welding of the tools for injection moulding of plastics and light metals. Tools for injection moulding of the car headlamps are highly polished in order to get a desirable quality of the injected part. Different light metals, glasses, elastomers, thermoplastics and thermosetting polymers are injected into the die cavity under high pressures resulting in the surface damages of the tool. Laser welding is the only suitable repair welding technique due to the very limited sputtering during deposition of the filler metal. Overlapping of the welds results in inhomogeneous hardness of the remanufactured surface. Results have shown strong correlation between hardness and surface waviness after final polishing of the repair welded surface.

  7. A novel surface-repairing technique for gun bore

    Institute of Scientific and Technical Information of China (English)

    SU Bing; YU Xu-dong; WU Bin; WANG Cheng-tao

    2005-01-01

    A novel surface-repairing technique for gun bore was investigated, which was combined with the merits such as anti-erosion wear, damage-repairing, and etc. It was accomplished by adhering a special rare earth nanocom posite evenly to the micro-surface of gun bore. The effectiveness of this technique was approved by the target-firing using a domestic automatic rifle with chromium-coated bore. Its characteristics were discussed based on the surface analyses of the rifle bore by secondary ion mass spectrometry(SIMS), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis.

  8. Synthesis and characterization of a lubricin mimic (mLub) to reduce friction and adhesion on the articular cartilage surface.

    Science.gov (United States)

    Lawrence, Alexandra; Xu, Xin; Bible, Melissa D; Calve, Sarah; Neu, Corey P; Panitch, Alyssa

    2015-12-01

    The lubricating proteoglycan, lubricin, facilitates the remarkable low friction and wear properties of articular cartilage in the synovial joints of the body. Lubricin lines the joint surfaces and plays a protective role as a boundary lubricant in sliding contact; decreased expression of lubricin is associated with cartilage degradation and the pathogenesis of osteoarthritis. An unmet need for early osteoarthritis treatment is the development of therapeutic molecules that mimic lubricin function and yet are also resistant to enzymatic degradation common in the damaged joint. Here, we engineered a lubricin mimic (mLub) that is less susceptible to enzymatic degradation and binds to the articular surface to reduce friction. mLub was synthesized using a chondroitin sulfate backbone with type II collagen and hyaluronic acid (HA) binding peptides to promote interaction with the articular surface and synovial fluid constituents. In vitro and in vivo characterization confirmed the binding ability of mLub to isolated type II collagen and HA, and to the cartilage surface. Following trypsin treatment to the cartilage surface, application of mLub, in combination with purified or commercially available hyaluronan, reduced the coefficient of friction, and adhesion, to control levels as assessed over macro-to micro-scales by rheometry and atomic force microscopy. In vivo studies demonstrate an mLub residency time of less than 1 week. Enhanced lubrication by mLub reduces surface friction and adhesion, which may suppress the progression of degradation and cartilage loss in the joint. mLub therefore shows potential for treatment in early osteoarthritis following injury.

  9. Laser repairing surface crack of Ni-based superalloy components

    Institute of Scientific and Technical Information of China (English)

    王忠柯; 叶和清; 许德胜; 黄索逸

    2001-01-01

    Surface crack of components of the cast nickel-base superalloy was repaired with twin laser beams under proper technological conditions. One laser beam was used to melt the substrate material of crack, and the other to fill in powder material to the crack region. The experimental results show that the surface crack with the width of 0.1~0.3mm could be repaired under the laser power of 3kW and the scanning speed of 6~8mm/s. The repaired deepness of crack region is below 6.5mm. The microstructure of repaired region is the cellular crystal, columnar crystal dendrite crystal from the transition region to the top filled layer. The phases in repaired region mainly consisted of supersaturated α-Co with plenty of Ni, some Cr and Al, Cr23C6, Co2B, Co-Ni-Mo, Ni4B3, TiSi and VSi. The hardness of filled layer in repaired region ranged from HV0.2450 to HV0.2500, and the hardness decreases gradually from the filled layer to joined zone.

  10. A peek into the possible future of management of articular cartilage injuries: gene therapy and scaffolds for cartilage repair.

    Science.gov (United States)

    Kim, Hubert T; Zaffagnini, Stefano; Mizuno, Shuichi; Abelow, Stephen; Safran, Marc R

    2006-10-01

    Two rapidly progressing areas of research will likely contribute to cartilage repair procedures in the foreseeable future: gene therapy and synthetic scaffolds. Gene therapy refers to the transfer of new genetic information to cells that contribute to the cartilage repair process. This approach allows for manipulation of cartilage repair at the cellular and molecular level. Scaffolds are the core technology for the next generation of autologous cartilage implantation procedures in which synthetic matrices are used in conjunction with chondrocytes. This approach can be improved further using bioreactor technologies to enhance the production of extracellular matrix proteins by chondrocytes seeded onto a scaffold. The resulting "neo-cartilage implant" matures within the bioreactor, and can then be used to fill cartilage defects.

  11. T2 star relaxation times for assessment of articular cartilage at 3 T: a feasibility study.

    Science.gov (United States)

    Mamisch, Tallal Charles; Hughes, Timothy; Mosher, Timothy J; Mueller, Christoph; Trattnig, Siegfried; Boesch, Chris; Welsch, Goetz Hannes

    2012-03-01

    T2 mapping techniques use the relaxation constant as an indirect marker of cartilage structure, and the relaxation constant has also been shown to be a sensitive parameter for cartilage evaluation. As a possible additional robust biomarker, T2* relaxation time is a potential, clinically feasible parameter for the biochemical evaluation of articular cartilage. The knees of 15 healthy volunteers and 15 patients after microfracture therapy (MFX) were evaluated with a multi-echo spin-echo T2 mapping technique and a multi-echo gradient-echo T2* mapping sequence at 3.0 Tesla MRI. Inline maps, using a log-linear least squares fitting method, were assessed with respect to the zonal dependency of T2 and T2* relaxation for the deep and superficial regions of healthy articular cartilage and cartilage repair tissue. There was a statistically significant correlation between T2 and T2* values. Both parameters demonstrated similar spatial dependency, with longer values measured toward the articular surface for healthy articular cartilage. No spatial variation was observed for cartilage repair tissue after MFX. Within this feasibility study, both T2 and T2* relaxation parameters demonstrated a similar response in the assessment of articular cartilage and cartilage repair tissue. The potential advantages of T2*-mapping of cartilage include faster imaging times and the opportunity for 3D acquisitions, thereby providing greater spatial resolution and complete coverage of the articular surface.

  12. T2 star relaxation times for assessment of articular cartilage at 3 T: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Mamisch, Tallal Charles [University Bern, Department of Orthopedic Surgery, Inselspital, Bern (Switzerland); University Bern, Magnetic Resonance Spectroscopy and Methodology, Department of Clinical Research, Bern (Switzerland); Hughes, Timothy [Siemens Medical Solutions, Erlangen (Germany); Mosher, Timothy J. [Penn State University College of Medicine, Musculoskeletal Imaging and MRI, Department of Radiology, Hershey, PA (United States); Mueller, Christoph [University of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Trattnig, Siegfried [Medical University of Vienna, MR Center - High Field MR, Department of Radiology, Vienna (Austria); Boesch, Chris [University Bern, Magnetic Resonance Spectroscopy and Methodology, Department of Clinical Research, Bern (Switzerland); Welsch, Goetz Hannes [University of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Medical University of Vienna, MR Center - High Field MR, Department of Radiology, Vienna (Austria)

    2012-03-15

    T2 mapping techniques use the relaxation constant as an indirect marker of cartilage structure, and the relaxation constant has also been shown to be a sensitive parameter for cartilage evaluation. As a possible additional robust biomarker, T2* relaxation time is a potential, clinically feasible parameter for the biochemical evaluation of articular cartilage. The knees of 15 healthy volunteers and 15 patients after microfracture therapy (MFX) were evaluated with a multi-echo spin-echo T2 mapping technique and a multi-echo gradient-echo T2* mapping sequence at 3.0 Tesla MRI. Inline maps, using a log-linear least squares fitting method, were assessed with respect to the zonal dependency of T2 and T2* relaxation for the deep and superficial regions of healthy articular cartilage and cartilage repair tissue. There was a statistically significant correlation between T2 and T2* values. Both parameters demonstrated similar spatial dependency, with longer values measured toward the articular surface for healthy articular cartilage. No spatial variation was observed for cartilage repair tissue after MFX. Within this feasibility study, both T2 and T2* relaxation parameters demonstrated a similar response in the assessment of articular cartilage and cartilage repair tissue. The potential advantages of T2*-mapping of cartilage include faster imaging times and the opportunity for 3D acquisitions, thereby providing greater spatial resolution and complete coverage of the articular surface. (orig.)

  13. Partial-thickness articular surface rotator cuff tears in patients over the age of 35: Etiology and intra-articular associations

    Directory of Open Access Journals (Sweden)

    Chetan S Modi

    2012-01-01

    Full Text Available Purpose: Partial-thickness articular-sided rotator cuff tears have a multifactorial etiology and are associated with degeneration of the tendon. They are often described as an injury of the young athlete, although they are also found in the older population. The aim of this study was to investigate the frequency and associations of partial-thickness articular-sided tears in patients over the age of 35 years. Design: Retrospective Materials and Methods: A retrospective study of all arthroscopic procedures for rotator cuff pathology in patients over the age of 35 years over a 2-year period by a single surgeon was performed. The included patients were divided into two groups based on the arthroscopic findings: those with a partial-thickness articular-sided rotator cuff tear and those with pure tendinopathy. The groups were then compared to identify the associated pathology with the rotator cuff lesions. 2×2 contingency table analysis and unpaired Student′s t-test were used for statistical analysis. Results: One hundred patients were included in the study of whom 62 had a partial articular-sided tear. Those with a partial articular-sided tear were older (P=0.0001, were more commonly associated with a documented injury (P=0.03, and more commonly had biceps degeneration (P=0.001 and synovitis (P=0.02 within the joint. Conclusion: Partial-thickness articular-sided tears are a common occurrence in patients requiring arthroscopic surgery for rotator cuff pathology over the age of 35 years. This probably reflects an injury in an already degenerate cuff. This would support the theory of intrinsic degeneration of the tendon in this age group and probably represent a different etiology to those seen in the young athletes. Level of Evidence: Level 3

  14. Giant Cell Tumor of Bone: Documented Progression over 4 Years from Its Origin at the Metaphysis to the Articular Surface

    Directory of Open Access Journals (Sweden)

    Colin Burke

    2016-01-01

    Full Text Available The exact location of origin for giant cell tumors of bone (GCTB remains controversial, as lesions are not routinely imaged early but rather late when the tumor is large and clinically symptomatic. At the time of diagnosis, GCTB are classically described as lucent, eccentric lesions with nonsclerotic margins, located within the epiphysis to a greater extent than the metaphysis. Here we present a case of a biopsy proven GCTB initially incidentally seen on MRI as a small strictly metaphyseal lesion, which over the course of several years expanded across a closed physis to involve the epiphysis and abut the articular surface/subchondral bone plate.

  15. Probing and repairing damaged surfaces with nanoparticle-containing microcapsules

    Science.gov (United States)

    Kratz, Katrina; Narasimhan, Amrit; Tangirala, Ravisubhash; Moon, Sungcheal; Revanur, Ravindra; Kundu, Santanu; Kim, Hyun Suk; Crosby, Alfred J.; Russell, Thomas P.; Emrick, Todd; Kolmakov, German; Balazs, Anna C.

    2012-02-01

    Nanoparticles have useful properties, but it is often important that they only start working after they are placed in a desired location. The encapsulation of nanoparticles allows their function to be preserved until they are released at a specific time or location, and this has been exploited in the development of self-healing materials and in applications such as drug delivery. Encapsulation has also been used to stabilize and control the release of substances, including flavours, fragrances and pesticides. We recently proposed a new technique for the repair of surfaces called `repair-and-go'. In this approach, a flexible microcapsule filled with a solution of nanoparticles rolls across a surface that has been damaged, stopping to repair any defects it encounters by releasing nanoparticles into them, then moving on to the next defect. Here, we experimentally demonstrate the repair-and-go approach using droplets of oil that are stabilized with a polymer surfactant and contain CdSe nanoparticles. We show that these microcapsules can find the cracks on a surface and selectively deliver the nanoparticle contents into the crack, before moving on to find the next crack. Although the microcapsules are too large to enter the cracks, their flexible walls allow them to probe and adhere temporarily to the interior of the cracks. The release of nanoparticles is made possible by the thin microcapsule wall (comparable to the diameter of the nanoparticles) and by the favourable (hydrophobic-hydrophobic) interactions between the nanoparticle and the cracked surface.

  16. Articular Cartilage Repair Using Marrow Stimulation Augmented with a Viable Chondral Allograft: 9-Month Postoperative Histological Evaluation

    Directory of Open Access Journals (Sweden)

    James K. Hoffman

    2015-01-01

    Full Text Available Marrow stimulation is frequently employed to treat focal chondral defects of the knee. However, marrow stimulation typically results in fibrocartilage repair tissue rather than healthy hyaline cartilage, which, over time, predisposes the repair to failure. Recently, a cryopreserved viable chondral allograft was developed to augment marrow stimulation. The chondral allograft is comprised of native viable chondrocytes, chondrogenic growth factors, and extracellular matrix proteins within the superficial, transitional, and radial zones of hyaline cartilage. Therefore, host mesenchymal stem cells that infiltrate the graft from the underlying bone marrow following marrow stimulation are provided with the optimal microenvironment to undergo chondrogenesis. The present report describes treatment of a trochlear defect with marrow stimulation augmented with this novel chondral allograft, along with nine month postoperative histological results. At nine months, the patient demonstrated complete resolution of pain and improvement in function, and the repair tissue consisted of 85% hyaline cartilage. For comparison, a biopsy obtained from a patient 8.2 months after treatment with marrow stimulation alone contained only 5% hyaline cartilage. These outcomes suggest that augmenting marrow stimulation with the viable chondral allograft can eliminate pain and improve outcomes, compared with marrow stimulation alone.

  17. Articular cartilage collagen: an irreplaceable framework?

    Directory of Open Access Journals (Sweden)

    D R Eyre

    2006-11-01

    Full Text Available Adult articular cartilage by dry weight is two-thirds collagen. The collagen has a unique molecular phenotype. The nascent type II collagen fibril is a heteropolymer, with collagen IX molecules covalently linked to the surface and collagen XI forming the filamentous template of the fibril as a whole. The functions of collagens IX and XI in the heteropolymer are far from clear but, evidently, they are critically important since mutations in COLIX and COLXI genes can result in chondrodysplasia syndromes. Here we review what is known of the collagen assembly and present new evidence that collagen type III becomes covalently added to the polymeric fabric of adult human articular cartilage, perhaps as part of a matrix repair or remodelling process.

  18. Resident mesenchymal progenitors of articular cartilage.

    Science.gov (United States)

    Candela, Maria Elena; Yasuhara, Rika; Iwamoto, Masahiro; Enomoto-Iwamoto, Motomi

    2014-10-01

    Articular cartilage has poor capacity of self-renewal and repair. Insufficient number and activity of resident mesenchymal (connective tissue) progenitors is likely one of the underlying reasons. Chondroprogenitors reside not only in the superficial zone of articular cartilage but also in other zones of articular cartilage and in the neighboring tissues, including perichondrium (groove of Ranvier), synovium and fat pad. These cells may respond to injury and contribute to articular cartilage healing. In addition, marrow stromal cells can migrate through subchondral bone when articular cartilage is damaged. We should develop drugs and methods that correctly stimulate resident progenitors for improvement of repair and inhibition of degenerative changes in articular cartilage. Copyright © 2014. Published by Elsevier B.V.

  19. 30 CFR 75.705-2 - Repairs to energized surface high-voltage lines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Repairs to energized surface high-voltage lines... Repairs to energized surface high-voltage lines. An energized high-voltage surface line may be repaired... on power circuits with a phase-to-phase nominal voltage no greater than 15,000 volts; (3)...

  20. The bony partial articular surface tendon avulsion lesion: an arthroscopic technique for fixation of the partially avulsed greater tuberosity fracture.

    Science.gov (United States)

    Bhatia, Deepak N; de Beer, Joe F; van Rooyen, Karin S

    2007-07-01

    The partial articular surface tendon avulsion (PASTA) is a common lesion that involves the supraspinatus tendon in most cases. We present an arthroscopic fixation technique for a previously undescribed lesion that may be considered a variant of the PASTA. The lesion involves a partial avulsion of the greater tuberosity with an intact deep insertion of the supraspinatus tendon into the fractured bone fragment and an intact superficial insertion of the supraspinatus into the unavulsed lateral aspect of the greater tuberosity: a "bony PASTA" lesion. The surgical technique involves the use of a 70 degree arthroscope to provide an "end-on" view of the pathology. A superior-medial transmuscular portal is used for anchor insertion and suture management; the portal avoids damage to the intact tendinous insertion of the supraspinatus, which can occur during transtendon anchor/screw insertion. Abduction of the arm to 50 degrees, after creation of the portal and passage of the cannula, permits an optimal "deadman" angle of anchor placement. An angled suture grasper is used to retrieve the 4 suture strands from the double-loaded suture anchor through the intact superficial and deep supraspinatus tendon fibers along the length of the fracture; these are tied as 2 mattress sutures over the tendon fibers in the subacromial space by use of sliding-locking knots. Adequacy of reduction is confirmed by intra-articular arthroscopic observation during movement of the extremity through its complete range of motion.

  1. Effects of low-intensity pulsed ultrasound for articular cartilage repair%低强度脉冲式超声对关节软骨的修复

    Institute of Scientific and Technical Information of China (English)

    刘洋; 刘宁; 刘昭铭; 郝振民; 王东来

    2016-01-01

    BACKGROUND:Articular cartilage injuries can result from a variety of causes. Conventional therapy cannot obtain the optimal clinical results. Low-intensity pulsed ultrasound has been shown to promote the repair of injured articular cartilage. OBJECTIVE:To investigate the effects of low-intensity pulsed ultrasound on the repair of injured articular cartilage. METHODS:Twenty New Zealand white rabbits were used to establish knee arthritis models and equal y randomized into study and control groups, respectively. Rabbits in the study group received low-intensity pulsed ultrasound treatment, and sham low-intensity pulsed ultrasound treatment was given in the control group. At 8 weeks after treatment, pathological change and histological scores in articular cartilage tissue col ected from both groups were determined. Moreover, the ultrastructure and type II col agen expression of chondrocytes were determined. Matrix metal oproteinase-13 mRNA expression was detected by quantitative real-time PCR. RESULTS AND CONCLUSION:At 8 weeks after treatment, toluidine blue staining showed a disordered arrangement of cel s, decreased number of cartilage cel s in each layer and cluster in the control group. Light disordered arrangement of cel s, decreased appearance of the superficial layer cel s and the cluster phenomenon were observed in the study group. Articular cartilage tissue scores were significantly decreased in the study group compared with the control group (P<0.05). The chondrocytes were smal , enlarged intracel ular mitochondria and rough endoplasmic reticulum, cytoplasmic swel ing, col agen fibrils coarse, wel developed Golgi apparatus, and nuclear fragmentation were observed in the control group. In addition, the normal structure of organel es disappeared and cel degeneration was observed in the control group. In the study group, the size of chondrocytes and the Golgi complex and other organel es were normal, and the protein polysaccharide granules were observed in the

  2. Research Progress of Tissue-engineered Cartilage to Repair Articular Cartilage Damage in Western and Chinese Medicine%组织工程软骨修复关节软骨损伤中西医研究进展

    Institute of Scientific and Technical Information of China (English)

    陈强; 蔡建平; 张爱国

    2012-01-01

    Articular cartilage damage and repair have been the thorny issue of orthopedic basic research and clinical treatment. Articular cartilage damage is becoming increasingly prominent, and has become a serious challenge faced by the multi-disciplinary trauma surgery, orthopedics, elderly subjects, as well as sports medicine. In this paper, the articular cartilage damage repair status, the tissue-engineered cartilage and Chinese medicine were made an overview of research on tissue engineered cartilage.%关节软骨的损伤和修复,一直以来是骨科基础研究与临床治疗的棘手问题.关节软骨损伤问题日益突出,俨然成为创伤外科、骨科、老年学科以及运动医学等多学科面临的严峻挑战.文章就关节软骨损伤修复现状、组织工程软骨技术及中药在组织工程软骨中的研究三方面做一概述.

  3. Tissue-engineered acellular matrix material:preparation and application in articular cartilage repair%脱细胞基质材料制备方法及在骨关节软骨损伤修复中的应用

    Institute of Scientific and Technical Information of China (English)

    赵玉果; 李明明

    2016-01-01

      结果与结论:①脱细胞基质组织工程材料交联后呈现为深蓝色,疏松多孔,直径为5 mm,硬度适中,具备一定的弹性;②苏木精-伊红染色不含有细胞碎屑及蓝染的核物质,不存在残留的细胞外基质;③甲苯胺蓝染色为蓝色材料支架孔隙率为90%,溶胀率为(1314±337)%;④脱细胞基质组织组材料1,3,5,7,9 d的A值显著高于纤维样组织组(P OBJECTIVE:To investigate the effect of tissue-engineered acelular matrix in articular cartilage repair. METHODS:Totaly 30 New Zealand rabbits were randomly alottedto fibroid tissue andacelular matrix groups (n=15 per group), and then articular cartilage defect models,4mmin diameter,were established at the white rabbitfemoral condyle. Acelular cartilage matrix scaffold was prepared using bovine knee cartilage, and model rats in the acelular matrix group were repaired with acelular cartilage matrix scaffold and the others in the fibroid tissue group repaired with fibroid tissues. Finaly, repair effects between two groups were compared. RESULTS AND CONCLUSION:The dark blue and porous tissue-engineered acelular matrix material could be found, with a diameter of 5mm and moderate hardness, and exhibited certain flexibility after cross-linking. Hematoxylin-eosin staining showed that cel debris,blue-stainednuclear materials and residual extracelular matrix disappeared. Toluidine blue staining found that the porosity of the blue scaffold was 90%, and the sweling ratio was (1314±337)%. The absorbance value in the acelular matrix group was significantly higher than that in the fibroid tissue group at 1, 3, 5, 7 and 9 days (P< 0.05). In the fibroid tissue group,defectsfiled withnewborn fibrous scars were overt. By contrast, in the acelularmatrix group, the white tissuescovered the defect regionwith smooth surface,and the woundwas basicaly healed,withanunclearboundaryafter 12weeks. Moreover, blue-stained, smal flattened cels appeared

  4. MORPHOMETRY OF THE ARTICULAR FACETS ON THE SUPERIOR, MEDIAL AND LATERAL SURFACES OF THE BODY OF TALUS AND ITS CLINICAL RELEVANCE

    Directory of Open Access Journals (Sweden)

    Goda Jatin B, Patel Shailesh M, Parmar Ajay M, Agarwal GC

    2015-07-01

    Full Text Available Background: In the formation of Ankle joint, tibio-fibular mortice receives superior, medial and lateral articular surfaces of body of Talus. Because of very limited availability of the data on the Morphometry of the articular facets on the Body of the dry human tali, this study was undertaken. Aims: To prepare the database on the articular facets on the superior, medial and lateral surfaces of body of talus, to find if there is statistically significant difference between both the sides of measurements and to compare the results with the previous studies. Methods and Material: 40 Dry Human Tali (20 Right and 20 Left were measured with Digital vernier caliper for the following Measurements: On the Trochlear surface: Medial length, Central length, Lateral length, Anterior width, Central width, Posterior width. On the lateral triangular articular facet: Central height, Central width. On the coma shaped medial articular facet: Central height, Central width. Results: Mean values of Medial, Central and Lateral lengths were 31.02, 30.39 and 29.63mm on Right side and 31.79, 30.65 and 29.45mm on Left side. Mean Anterior, Central and Posterior widths were 28.87, 28.16 and 21.59mm on right side and 29.08, 27.54 and 21.78mm on left side. On the medial articular surface, mean central height was 11.93mm on the right side and 11.29mm on the left side, Mean central width was 27.94mm on the right side and 28.29mm on the left side. On the lateral articular surface, mean central height was 22.14mm on the right side and 22.63mm on the left side. Mean central width was 18.93mm on the right side and 18.99mm on the left side. There is no significant difference between right and left sides of measurements. Conclusion: The trochlear articular surface is wider in front, measurements of opposite talus bone can be used as a control during talus bone replacement surgery, it may help surgeons to plan pre-operatively the complex talar fracture surgeries, to design accurate

  5. Solvent-mediated repair and patterning of surfaces by AFM

    Energy Technology Data Exchange (ETDEWEB)

    Elhadj, S; Chernov, A; De Yoreo, J

    2007-10-30

    A tip-based approach to shaping surfaces of soluble materials with nanometer-scale control is reported. The proposed method can be used, for example, to eliminate defects and inhomogeneities in surface shape, repair mechanical or laser-induced damage to surfaces, or perform 3D lithography on the length scale of an AFM tip. The phenomenon that enables smoothing and repair of surfaces is based on the transport of material from regions of high- to low-curvature within the solution meniscus formed in a solvent-containing atmosphere between the surface in question and an AFM tip scanned over the surface. Using in situ AFM measurements of the kinetics of surface remodeling on KDP (KH{sub 2}PO{sub 4}) crystals in humid air, we show that redistribution of solute material during relaxation of grooves and mounds is driven by a reduction in surface free energy as described by the Gibbs-Thomson law. We find that the perturbation from a flat interface evolves according to the diffusion equation where the effective diffusivity is determined by the product of the surface stiffness and the step kinetic coefficient. We also show that, surprisingly, if the tip is instead scanned over or kept stationary above an atomically flat area of the surface, a convex structure is formed with a diameter that is controlled by the dimensions of the meniscus, indicating that the presence of the tip and meniscus reduces the substrate chemical potential beneath that of the free surface. This allows one to create nanometer-scale 3D structures of arbitrary shape without the removal of substrate material or the use of extrinsic masks or chemical compounds. Potential applications of these tip-based phenomena are discussed.

  6. 运动性关节软骨损伤修复材料的选择及其生物力学特征%Selection and biomechanical features of repair materials for exercise-induced articular cartilage injury

    Institute of Scientific and Technical Information of China (English)

    王洪博; 刘东兴; 任志杰; 尹树仁

    2011-01-01

    背景:关节软骨是无血管、淋巴管和神经的组织,通常情况下软骨细胞不能进行有丝分裂,这导致自身修复能力有限.生理负荷下,关节软骨经常处在应力环境中.根据软骨自身的结构和特点,作为人工软骨的替代材料应具有良好的生物力学性能.目的:总结运动性关节软骨损伤修复材料的应用进展及其生物替代材料的生物力学特征.方法:以"关节软骨,生物材料,生物力学"为中文关键词,以" tissue enginneering,articular cartilage,scaffold material,biomechanics" 为英文关键词,采用计算机检索中国期刊全文数据库、PubMed数据库1993-01/2010-10相关文章.纳入与运动有关的关节软骨损伤修复、目前常用于修复关节软骨损伤的生物材料以及生物替代材料的生物力学特征研究文章;排除重复研究或Meta分析类文章.以20篇文献为主重点对运动性关节软骨缺损修复材料的生物力学特征进行讨论.结果与结论:关节软骨是一种各向异性、非均质、具有黏弹性并充满液体的可渗透物质,具有独特的力学性能.损伤的关节软骨在生物力学方面均与原来的软骨不同,且极易退变.骨软骨柱移植力学性能近期效果最佳;脱细胞软骨基质、小肠黏膜下基质具有一定的力学强度;普通聚乙烯醇水凝胶的最大缺陷是力学性能的不足;聚乙烯醇材料其良好的柔韧性和高弹性能,具有与人关节软骨相似的力学性能;n-HA浆料与聚酰胺66在溶剂中复合,无论在力学性能还是化学组成上都与自然骨相似.提示在众多关节软骨替代材料中,无论是人工合成材料、天然材料、复合材料其生物力学性能各有不同,且目前还无法再造与天然生成的软骨具有相同力学性能的软骨组织.%BACKGROUND: Articular cartilage is non-vascular, lymphatic and nerve tissue, cartilage cells usually can not perform mitosis,resulting in limited ability to repair

  7. A specific mechanomodulatory role for p38 MAPK in embryonic joint articular surface cell MEK-ERK pathway regulation.

    Science.gov (United States)

    Lewthwaite, Jo C; Bastow, Edward R; Lamb, Katherine J; Blenis, John; Wheeler-Jones, Caroline P D; Pitsillides, Andrew A

    2006-04-21

    Mechanisms regulating cell behavior and extracellular matrix composition in response to mechanical stimuli remain unresolved. Our previous studies have established that the MEK-ERK cascade plays a specific role in the mechano-dependent joint formation process by promoting the assembly of pericellular matrices reliant upon hyaluronan (HA) for their integrity. Here we demonstrate: (i) novel cross-talk between p38 MAPK and MEK-ERK signaling pathways that is specific for mechanical stimuli and (ii) a role for p38 MAPK in facilitating HA production by cells derived from the articular surface of embryonic chick tibiotarsal joints. We find that p38 MAPK blockade restricts pericellular assembly of HA-rich matrices and reduces basal as well as mechanical strain-induced release of HA. p38 MAPK blockers potentiated early strain-induced increases but restricted sustained increases in MEK/ERK phosphorylation at later times; c-Fos hyperphosphorylation at threonine 325 was found to parallel this p38 MAPK-mediated modulation of ERK activation. In contrast, p38 MAPK inhibitors had no detectable effect on the ERK activation induced by fibroblast growth factor 2 or pervanadate, a phosphatase inhibitor, and MEK inhibitors did not influence p38 MAPK phosphorylation, confirming both the specificity and unidirectionality of p38 MAPK-ERK cross-talk. Immunochemical and immunoblotting studies revealed constitutive p38 MAPK activation in cells at, or derived from, developing articular joint surfaces. Unlike the MEK-ERK pathway, however, p38 MAPK was not further stimulated by mechanical stimulation in vitro. Thus, p38 MAPK specifically facilitates ERK activation and downstream signaling in response to mechanical stimuli. These results suggest that constitutively active p38 MAPK serves an essential, permissive role in mechanically induced changes in ERK activation and in the accumulation of HA-rich extracellular matrices that serve a key role in joint development.

  8. Shock Wave-Stimulated Periosteum for Cartilage Repair

    Science.gov (United States)

    2015-03-01

    AD_________________ Award Number: W81XWH-10-1-0914 TITLE: Shock Wave-Stimulated Periosteum for Cartilage Repair PRINCIPAL INVESTIGATOR...30Sep2010 – 1Dec2014 4. TITLE AND SUBTITLE Shock Wave-Stimulated Periosteum for Cartilage Repair 5a. CONTRACT NUMBER W81XWH-10-1-0914 5b. GRANT NUMBER... shock wave (ESW)-stimulated periosteum improves cartilage repair when it is used as an autograft to fill a defect in the articular surface of goats. A

  9. Evaluation of New Repair Methods for Seal Surface Defects on Reusable Solid Rocket Motor (RSRM) Hardware

    Science.gov (United States)

    Stanley, Stephanie; Selvidge, Shawn

    2003-01-01

    The focus of the evaluation was to develop a back-up method to cell plating for the improvement or repair of seal surface defects within D6-AC steel and 7075-T73 aluminum used in the RSRM program. Several techniques were investigated including thermal and non-thermal based techniques. Ideally the repair would maintain the inherent properties of the substrate without losing integrity at the repair site. The repaired sites were tested for adhesion, corrosion, hardness, microhardness, surface toughness, thermal stability, ability to withstand bending of the repair site, and the ability to endure a high-pressure water blast without compromising the repaired site. The repaired material could not change the inherent properties of the substrate throughout each of the test in order to remain a possible technique to repair the RSRM substrate materials. One repair method, Electro-Spark Alloying, passed all the testing and is considered a candidate for further evaluation.

  10. Repairing articular cartilage defects in rabbits using poly(lactic-co-glycolic acid)%聚乳酸/聚羟基乙酸共聚物修复髌股关节软骨缺损

    Institute of Scientific and Technical Information of China (English)

    崔玉明; 伍骥; 胡蕴玉

    2011-01-01

    BACKGROUND:Traditional methods to repair cartilage damage are prone to induce degeneration. Poly(lactic-co-glycolic acid)(PLGA) has good biocompatibility, its degradation rate can be adjusted according to the requirements, has a potential application prospect in the repair of cartilage damage.OBJECTIVE:To study the feasibility of repairing articular cartilage defect in rabbits using PLGA as a carrier.METHODS:Two-month-old New Zealand white rabbits were selected, and the marrow stromal cells were induced into chondroncytes.The third passage of cells and the PLGA were co-cultured for 24 hours, then PLGA-cell composites were prepared ready. Defects were made in femoral condyles of rabbit patellofemoral joint, and the right 36 knees were treated with PLGA-cell composites, the left 18knees was implanted with PLGA only, the other 18 knees were left untreated as control group. At 4, 8, 12, 24, 36, 48 weeks after operation, the animals were killed and the newly formed tissues were observed grossly and graded histologically.RESULRS AND CONCLUSION:After the defects in rabbits were repaired using PLGA-cell composite, the chondrocytes distributed uniformly, the color and the luster of the defects were similar to that of the normal cartilage, and was ill-demarcated from the surrounding normal cartilage. The cells on the surface paralleled to joint surface, and the cells in the deep layer arranged disorderly. The cells clustered together, the matrix was extensively metachromatic. The subchond ral bone formed, the tide mark basically recovered, and the new cartilage integrated with normal cartilage finely. As for only PLGA group and untreated group,chondrocytes proliferated in the border, but on the bottom, there were mainly fibrous tissues. Chondroncytes derived from marrow stromal cell are ideal seed cells for repairing articular cartilage defect. PLGA can be used as a suitable matrix material for the repair of cartilage defect and may have a good prospect for clinical use.%

  11. Identification and clonal characterisation of a progenitor cell sub-population in normal human articular cartilage.

    Directory of Open Access Journals (Sweden)

    Rebecca Williams

    Full Text Available BACKGROUND: Articular cartilage displays a poor repair capacity. The aim of cell-based therapies for cartilage defects is to repair damaged joint surfaces with a functional replacement tissue. Currently, chondrocytes removed from a healthy region of the cartilage are used but they are unable to retain their phenotype in expanded culture. The resulting repair tissue is fibrocartilaginous rather than hyaline, potentially compromising long-term repair. Mesenchymal stem cells, particularly bone marrow stromal cells (BMSC, are of interest for cartilage repair due to their inherent replicative potential. However, chondrocyte differentiated BMSCs display an endochondral phenotype, that is, can terminally differentiate and form a calcified matrix, leading to failure in long-term defect repair. Here, we investigate the isolation and characterisation of a human cartilage progenitor population that is resident within permanent adult articular cartilage. METHODS AND FINDINGS: Human articular cartilage samples were digested and clonal populations isolated using a differential adhesion assay to fibronectin. Clonal cell lines were expanded in growth media to high population doublings and karyotype analysis performed. We present data to show that this cell population demonstrates a restricted differential potential during chondrogenic induction in a 3D pellet culture system. Furthermore, evidence of high telomerase activity and maintenance of telomere length, characteristic of a mesenchymal stem cell population, were observed in this clonal cell population. Lastly, as proof of principle, we carried out a pilot repair study in a goat in vivo model demonstrating the ability of goat cartilage progenitors to form a cartilage-like repair tissue in a chondral defect. CONCLUSIONS: In conclusion, we propose that we have identified and characterised a novel cartilage progenitor population resident in human articular cartilage which will greatly benefit future cell

  12. The influence of surface porosity on gap-healing around intra-articular implants in the presence of migrating particles

    DEFF Research Database (Denmark)

    Rahbek, Ole; Kold, Soren; Zippor, Berit;

    2005-01-01

    -pore coating (Fi) were inserted intra-articular in exact fit or with a 0.75 mm peri-implant gap. A weight-loaded implant device in the distal femur was used. We used a randomized paired design in eight dogs. PE particles were injected repeatedly intra-articular in the knee until the dogs were killed after 8...

  13. Repairability of Compomers with Different Methods of Surface Conditioning

    Directory of Open Access Journals (Sweden)

    P.Samimi

    2005-06-01

    Full Text Available Statement of Problem: Considering the cost and amount of time and also the quantity of tooth loss in the process of cavity preparation, repair of the restoration instead of itsreplacement would be much more efficient.Purpose: The aim of this study was to determine the effect of different methods of surface conditioning on the shear bond strength of repaired compomers.Materials and Methods: Sixty blocks of compomer were prepared in acrylic molds and then they were randomly divided into five groups of 12. Group I (control groupreceived no treatment. The remaining samples were immersed in 37 ºC distilled water for one week, then the surfaces were roughened with a coarse diamond bur. Samples ineach group were prepared by different surface treatment and conditioning: In group II specimens were conditioned with 35% phosphoric acid for 20s. Specimens in group III were etched with 10% polyacrylic acid for 20s. In group IV 1.23% acidulated phosphatefluoride was applied for 30s, and compomer surfaces were sandblasted with 50μm Al2O3 powder in group V. After the initial preparations, all groups were treated with silane and resin before bonding of the second mix of compomer. Shear forces were applied with a universal testing machine at a cross-head speed of 5mm/min. The data were analyzed using one-way ANOVA and Duncan's multiple range tests.Results: The mean shear bond strengths and standard deviations (in parentheses for groups I to V were 31.56(10.86, 20.02(5.49, 17.74(7.34, 19.31(4.31 and 27.7(6.33MPa, respectively. The mean bond strengths for Groups I and V were significantly higher than that of the other groups (P<0.05.Conclusion: The results showed that among the surface treatments used in this study,sandblasting with alumina could be the best surface preparation method for repairing compomer restorations.

  14. Leukocyte and Platelet Rich Plasma (L-PRP) Versus Leukocyte and Platelet Rich Fibrin (L-PRF) For Articular Cartilage Repair of the Knee: A Comparative Evaluation in an Animal Model.

    Science.gov (United States)

    Kazemi, Davoud; Fakhrjou, Ashraf

    2015-10-01

    Articular cartilage injuries of the knee are among the most debilitating injuries leading to osteoarthritis due to limited regenerative capability of cartilaginous tissue. The use of platelet concentrates containing necessary growth factors for cartilage healing has recently emerged as a new treatment method. The efficacy of two types of different platelet concentrates were compared in the treatment of acute articular cartilage injuries of the knee in an animal model. Eighteen adult Iranian mixed breed male dogs were used to conduct this experimental study. Full thickness articular cartilage defects (diameter 6 mm, depth 5 mm) were created in the weight bearing area of femoral condyles of both hind limbs in all dogs (n = 72). Twelve dogs were randomly selected to receive treatment and their right and left hind limb defects were treated by L-PRP and L-PRF implantation respectively, while no treatment was undertaken in six other dogs as controls. The animals were euthanized at 4, 16 and 24 weeks following surgery and the resultant repair tissue was investigated macroscopically and microscopically. At each sampling time, 4 treated dogs and 2 control dogs were euthanized, therefore 8 defects per group were evaluated. Mean macroscopic scores of the treated defects were higher than the controls at all sampling times with significant differences (P PRF treated and control defects (10.13 vs. 8.37) and L-PRP treated and control defects (10 vs. 8.5) at 4 and 16 weeks, respectively. A similar trend in mean total microscopic scores was observed with a significant difference (P PRF could be used to effectively promote the healing of articular cartilage defects of the knee.

  15. Study of the collagen structure in the superficial zone and physiological state of articular cartilage using a 3D confocal imaging technique

    Directory of Open Access Journals (Sweden)

    Zheng Ming H

    2008-07-01

    Full Text Available Abstract Introduction The collagen structure in the superficial zone of articular cartilage is critical to the tissue's durability. Early osteoarthritis is often characterized with fissures on the articular surface. This is closely related to the disruption of the collagen network. However, the traditional histology can not offer visualization of the collagen structure in articular cartilage because it uses conventional optical microscopy that does not have insufficient imaging resolution to resolve collagen from proteoglycans in hyaline articular cartilage. This study examines the 3D collagen network of articular cartilage scored from 0 to 2 in the scoring system of International Cartilage Repair Society, and aims to develop a 3D histology for assessing early osteoarthritis. Methods Articular cartilage was visually classified into five physiological groups: normal cartilage, aged cartilage, cartilage with artificial and natural surface disruption, and fibrillated. The 3D collagen matrix of the cartilage was acquired using a 3D imaging technique developed previously. Traditional histology was followed to grade the physiological status of the cartilage in the scoring system of International Cartilage Repair Society. Results Normal articular cartilage contains interwoven collagen bundles near the articular surface, approximately within the lamina splendens. However, its collagen fibres in the superficial zone orient predominantly in a direction spatially oblique to the articular surface. With age and disruption of the articular surface, the interwoven collagen bundles are gradually disappeared, and obliquely oriented collagen fibres change to align predominantly in a direction spatially perpendicular to the articular surface. Disruption of the articular surface is well related to the disappearance of the interwoven collagen bundles. Conclusion A 3D histology has been developed to supplement the traditional histology and study the subtle changes in

  16. Immediate repair bond strengths of microhybrid, nanohybrid and nanofilled composites after different surface treatments

    NARCIS (Netherlands)

    Rinastiti, Margareta; Siswomihardjo, Widowati; Busscher, Henk J.; Ozcan, Mutlu

    2010-01-01

    Objectives: To evaluate immediate repair bond strengths and failure types of resin composites with and without surface conditioning and characterize the interacting composite surfaces by their surface composition and roughness. Methods: Microhybrid, nanohybrid and nanofilled resin composites were ph

  17. Immunophenotypic analysis of human articular chondrocytes: changes in surface markers associated with cell expansion in monolayer culture.

    Science.gov (United States)

    Diaz-Romero, Jose; Gaillard, Jean Philippe; Grogan, Shawn Patrick; Nesic, Dobrila; Trub, Thomas; Mainil-Varlet, Pierre

    2005-03-01

    Cartilage tissue engineering relies on in vitro expansion of primary chondrocytes. Monolayer is the chosen culture model for chondrocyte expansion because in this system the proliferative capacity of chondrocytes is substantially higher compared to non-adherent systems. However, human articular chondrocytes (HACs) cultured as monolayers undergo changes in phenotype and gene expression known as "dedifferentiation." To gain a better understanding of the cellular mechanisms involved in the dedifferentiation process, our research focused on the characterization of the surface molecule phenotype of HACs in monolayer culture. Adult HACs were isolated by enzymatic digestion of cartilage samples obtained post-mortem. HACs cultured in monolayer for different time periods were analyzed by flow cytometry for the expression of cell surface markers with a panel of 52 antibodies. Our results show that HACs express surface molecules belonging to different categories: integrins and other adhesion molecules (CD49a, CD49b, CD49c, CD49e, CD49f, CD51/61, CD54, CD106, CD166, CD58, CD44), tetraspanins (CD9, CD63, CD81, CD82, CD151), receptors (CD105, CD119, CD130, CD140a, CD221, CD95, CD120a, CD71, CD14), ectoenzymes (CD10, CD26), and other surface molecules (CD90, CD99). Moreover, differential expression of certain markers in monolayer culture was identified. Up-regulation of markers on HACs regarded as distinctive for mesenchymal stem cells (CD10, CD90, CD105, CD166) during monolayer culture suggested that dedifferentiation leads to reversion to a primitive phenotype. This study contributes to the definition of HAC phenotype, and provides new potential markers to characterize chondrocyte differentiation stage in the context of tissue engineering applications. 2004 Wiley-Liss, Inc.

  18. Cross-linked type I and type II collagenous matrices for the repair of full-thickness articular cartilage defects--a study in rabbits.

    NARCIS (Netherlands)

    Buma, P.; Pieper, J.S.; Tienen, Tony van; Susante, J.L.C. van; Kraan, P.M. van der; Veerkamp, J.H.; Berg, W.B. van den; Veth, R.P.H.; Kuppevelt, A.H.M.S.M. van

    2003-01-01

    The physico-chemical properties of collagenous matrices may determine the tissue response after insertion into full-thickness articular cartilage defects. In this study, cross-linked type I and type II collagen matrices, with and without attached chondroitin sulfate, were implanted into full-thickne

  19. Eletroterapia no processo de reparação da superfície articular de coelhos Electrotherapy on the healing process in the articular surface of rabbits

    Directory of Open Access Journals (Sweden)

    Tayse Domingues de Souza

    2001-10-01

    Full Text Available Os efeitos da eletroestimulação pós-operatória no processo de reparação de falhas osteocondrais induzidas no sulco troclear de 36 coelhos adultos foram avaliados histologicamente. O grupo controle apresentou tecido de granulação típico, com duas semanas de pós-operatório (PO; cartilagem hialina foi observada após quatro e sete semanas de PO e a reconstituição do osso subcondral excisado limitou-se ao fundo da falha, até sete semanas de PO. No grupo I (eletroestimulado diariamente, o tecido de granulação apresentou vascularização exuberante após duas semanas de PO; após sete semanas de PO, o tecido de reparação permaneceu indiferenciado superficialmente, com formação de novo osso subcondral até o nível da junção osteocondral preexistente. No grupo II (eletroestimulado em dias alternados, os animais responderam de duas maneiras: através da reparação com cartilagem hialina e osteogênese reduzida, semelhante ao grupo controle; ou pela formação de tecido indiferenciado e osteogênese intensa, como no grupo I. Concluiu-se que a eletroestimulação pós-operatória realizada impediu a diferenciação tecidual em cartilagem hialina em coelhos. Por outro lado, a ossificação endocondral foi acelerada, observando-se reconstituição do osso subcondral até o nível da junção osteocondral preexistente nos animais tratados com este método. Em face da importância do osso subcondral na manutenção da integridade do tecido de reparação, a eletroestimulação é benéfica na fase inicial (quatro semanas da reparação de falhas osteocondrais.The effects of postooperative electrotherapy in the repair of full-thickness osteochondral defects in the troclear groove of 36 adult rabbits were evaluated histologically. In the control group, granulation tissue was present two weeks post-operatively (PO; hyaline cartilage was observed at four and at seven weeks PO; subchondral bone regeneration was limited to the deeper portions

  20. Microperioteum-scaffolded repair of large, full-thickness defect of articular cartilage%微粒骨膜-三维支架修复大面积关节软骨缺损

    Institute of Scientific and Technical Information of China (English)

    李亚屏; 赵庆安; 董平; 汤华林; 王爱康; 俞文英; 宋晓萍; 韩成钢; 陈先武

    2008-01-01

    Objective To explore the effectiveness and the feasibility of microperiosteum-scaffol-ded repair of larger defect of articular cartilage. Methods A larger (4.5 ram-in diameter) ,full-thlckness defect of articular cartilage were made in the femoral groove of New Zealand White rabbits. Microperioste-tun was prepared and dispersed in fibering glue, then transplanted into defects by means of tapecasting. The contralateral knee served as a control : only fibering glue was transplanted into defects in the same way. The distal parts of the femur were harvested at the end of 3 h,4 days and 1,2,4,8,12,24 weeks postoperative-ly ,and were examined grossly and histologically. The tissues were stained with HE, Masson (for collagen of articurlar cartilage) and safranin-O (for GAG). Results The microperiosteum- fibering glue could be prepared simply,and could be transplanted freely into defects by the means of tapecasting. This approach could be accomplished easily by no more than one operation. Throughout the defects were repaired as MSCs of the microperiosteum proliferated tremendously and secreted special cartilage matrix; The new cartilage was the same as the surrounding normal cartilage in its thickness, cellular histology, special staining for collage and GAG, and was excellently integrated with surrounding cartilage and subcartilage bone as well.There were significant differences (P <0.01) in histologic scores between control group and microperios-team-scaffolded graft group at the end of 4,8,12,24 weeks postoperatively. Conclusion The approach can construct tissue complex, and microperinsteum- fibering glue can transplanted freely by the means of tapecasting and repair the defects of articurlar cartilage; It may be a useful alternative in the repair of large,full-thickness defect of joint surfaces.%目的 探讨微粒骨膜-三维支架修复大面积关节软骨缺损的有效性和可行性.方法 于兔股骨滑车关节面制作直径4.5 mm深达软骨下骨板的全

  1. Research on clinical application of bone transplantation on repairing articular facet of distal radius%骨移植术修复桡骨远端关节面的临床应用研究

    Institute of Scientific and Technical Information of China (English)

    林勇; 曾秋涛; 林雪萍; 阮张涛

    2015-01-01

    Objective To investigate the therapeutic effect of the iliac bone graft to reconstruct and repair the articular surface of the distal radius.Methods During June, 2012 to Sept.2014, application of external fixator and operation of open reduction an interal fixation and ilia bone grafting on the treament of distal radius comminuted intraarticular fractures with articular surface defect in 15 cases.Results After operation, 14 cases of X-ray flim showed the articular surface separation and dislocation <2.0mm in 4 cases, <1.0mm in 10 cases, palmar tilt to 0 to 15 degrees, ulna inclination 20 to 30 degrees, 14 cases without shortening of bone, fracture healing, healing time was 10 to 16 weeks. In 1 patients with craniocerebral injury patients for postoperative owe cooperation, forced wrist external fixator and impact, causing bracket loosening, loss of reduction and fracture healing fracture, although after the remedial operation treament, wrist jiont funtion recovery in patients with poor.All 15 cases were followed up for 4 to 18 months, all patients with Gartland-Werley funtioal score standard evaluation funtion of wrist jiont, excellent (0~2 score ) in 4 cases, Good (3~8 score ) in 7 cases, (9~14 score ) in 3cases, (more than 15score ) in 1 case.Conclusions This technique can reconstruct the radius distal metaphysis, can solve joint surface of the distal radius bone defect caused by instability of some movement, and can save the wrist joint, reduce early chances for radiocarpal fusion, reduce or mitigate the occurrence of traumatic arthritis.%目的:探讨取髂骨植骨术重建、修复桡骨远端关节面的疗效结果。方法2012年6月至2014年9月,应用外固定支架+手术切开复位内固定术+取髂骨植骨术治疗桡骨远端严重关节内粉碎骨折合并关节面缺损15例。结果术后14例X线片显示:关节面分离和错位<1.0 mm 10例,<2.0 mm 4例,掌倾角为0~15°,尺倾角20~30°,14例无骨短缩,

  2. A comparison of tool-repair methods using CO 2 laser surfacing and arc surfacing

    Science.gov (United States)

    Grum, J.; Slabe, J. M.

    2003-03-01

    The life of loaded machine elements and the vital parts of tools can be successfully extended by systematic maintenance and the timely repair of damaged surfaces. It has been proved that with the regular maintenance of tool parts the cost of the tool in the price of a finished product can be considerably reduced. It is a very economical practise to manufacture certain parts from low-cost, tough structural steel on which a layer of wear-resistant alloy has been surfaced. In such a case the volume fraction of the surfaced layer is usually much lower than 10% of the total volume of the tool or the machine element. In this paper, we report some of our latest results involving comparative studies of repair surfacing on maraging steel and the cladding of common structural steel with a Ni-Co-Mo alloy similar to the maraging steel using a laser process and submerged-arc surfacing. The results are based on micro-structural and micro-chemical analyses of the surfaced layer and are supported by analyses of the micro-hardness and the residual stresses, carried out on suitably adapted flat specimens.

  3. Effect of various surface treatments on the bond strength of porcelain repair.

    Science.gov (United States)

    Saraç, Duygu; Saraç, Yakup Sinasi; Külünk, Safak; Erkoçak, Ayca

    2013-01-01

    This study evaluated the effect of surface treatments on the repair strength of composite resin on a feldspathic ceramic. Ninety ceramic specimens were divided into six groups. In the experimental groups, 4% hydrofluoric acid etching, Er:YAG laser irradiation, CO2 laser irradiation, airborne-particle abrasion, and silica coating were used as surface treatments. After the application of a porcelain repair kit, composite resin was placed on the treated surfaces. After a shear bond strength test, data were statistically analyzed (α = .05). Surface treatments increased the repair bond strength values (P < .05). Airborne particle abrasion and silica coating were found to be the most effective. CO2 laser showed higher repair strength values than Er:YAG laser.

  4. Non-machined Surface Protection Process of Electrochemical Machining Based on Repaired Turbine Blade

    Directory of Open Access Journals (Sweden)

    LIU Wei-dong

    2016-11-01

    Full Text Available In order to improve the efficiency of turbine blade repairing, protection processes of non-machined surface in Electrochemical Machining (ECM based on blade repairing were studied. Mathematical model of electric field was developed to obtain current density distribution on anode surface, and to study the repairing principle and consequently analyze the defects forming mechanism by conventional electrolytic repair process. Sacrificial layer process was proposed to protect the non-machined surface in this work and an experimental system was developed to shape overlay welded TC4 blades. The results show that directly shaping process and insulated layer process produce stray dissolution and "stair" defects respectively,while sacrificial layer process achieves acceptable machining performance. With shaping time of 60s, the efficiency is improved; shaped blades have higher precision and surface roughness is Ra≤0.6μm, and with higher repeatability, the design requirements can be met.

  5. Articular cartilage surface roughness as an imaging-based morphological indicator of osteoarthritis: A preliminary investigation of osteoarthritis initiative subjects.

    Science.gov (United States)

    Newton, Michael D; Osborne, Jeffrey; Gawronski, Karissa; Baker, Kevin C; Maerz, Tristan

    2017-04-29

    Current imaging-based morphometric indicators of osteoarthritis (OA) using whole-compartment mean cartilage thickness (MCT) and volume changes can be insensitive to mild degenerative changes of articular cartilage (AC) due to areas of adjacent thickening and thinning. The purpose of this preliminary study was to evaluate cartilage thickness-based surface roughness as a morphometric indicator of OA. 3D magnetic resonance imaging (MRI) datasets were collected from osteoarthritis initiative (OAI) subjects with Kellgren-Lawrence (KL) OA grades of 0, 2, and 4 (n = 10/group). Femoral and tibial AC volumes were converted to two-dimensional thickness maps, and MCT, arithmetic surface roughness (Sa ), and anatomically normalized Sa (normSa ) were calculated. Thickness maps enabled visualization of degenerative changes with increasing KL grade, including adjacent thinning and thickening on the femoral condyles. No significant differences were observed in MCT between KL grades. Sa was significantly higher in KL4 compared to KL0 and KL2 in the whole femur (KL0: 0.55 ± 0.10 mm, KL2: 0.53 ± 0.09 mm, KL4: 0.79 ± 0.18 mm), medial femoral condyle (KL0: 0.42 ± 0.07 mm, KL2: 0.48 ± 0.07 mm, KL4: 0.76 ± 0.22 mm), and medial tibial plateau (KL0: 0.42 ± 0.07 mm, KL2: 0.43 ± 0.09 mm, KL4: 0.68 ± 0.27 mm). normSa was significantly higher in KL4 compared to KL0 and KL2 in the whole femur (KL0: 0.22 ± 0.02, KL2: 0.22 ± 0.02, KL4: 0.30 ± 0.03), medial condyle (KL0: 0.17 ± 0.02, KL2: 0.20 ± 0.03, KL4: 0.29 ± 0.06), whole tibia (KL0: 0.34 ± 0.04, KL2: 0.33 ± 0.05, KL4: 0.48 ± 0.11) and medial plateau (KL0: 0.23 ± 0.03, KL2: 0.24 ± 0.04, KL4: 0.40 ± 0.10), and significantly higher in KL2 compared to KL0 in the medial femoral condyle. Surface roughness metrics were sensitive to degenerative morphologic changes, and may be useful in OA characterization and early diagnosis

  6. Repair, Evaluation, Maintenance, and Rehabilitation Research Program Overlays on Horizontal Concrete Surfaces: Case Histories

    Science.gov (United States)

    1994-02-01

    thermal expansion and contraction and autogenous shrinkage. No attempt was made to repair the cracks. During an inspection in August of 1984, it was...LATEX- ’ * """* 9 MODIFIED CONCRETE SLOPE PATCH IF NECESSARY EXOSTING CRACK TO MAINTAIN DRAINAGE Figure 27. Typical surface repair, Mississippi River...102-mm) deep densely graded aggregate base. The sand base extended to the ditch foreslopes to provide drainage of subbase. The average daily

  7. Effect of surface treatments and bonding agents on the bond strength of repaired composites.

    Science.gov (United States)

    Cavalcanti, Andrea Nóbrega; De Lima, Adriano Fonseca; Peris, Alessandra Rezende; Mitsui, Fabio Hiroyuki Ogata; Marchi, Giselle Maria

    2007-01-01

    An adequate repair procedure depends on high bond strength between the existing composite and the new composite. To evaluate the effect of surface treatments and bonding procedures on the bond strength of repairs performed 24 hours after composite polymerization. Composite specimens were stored in distilled water at 37 degrees C for 24 hours. Specimens were allocated into 12 groups (N=10) according to the combination of surface treatment (none, air abrasion, diamond bur) and bonding procedure (none, Single Bond after H(3)PO(4) cleansing, Clearfil SE Bond after H(3)PO(4) cleansing, Clearfil SE Bond without H(3)PO(4) cleansing). The ultimate tensile strength (UTS) of the composite was tested in nonrepaired specimens. Twenty-four hours after repair, specimens were sectioned into three slabs and trimmed to an hourglass shape (1 mm(2) area). Slabs were tested under tension and mean bond strengths analyzed with two-way analysis of variance/Tukey and Dunnett tests (alpha=5%). Two groups resulted in repair bond strengths similar to composite UTS: air abrasion combined with Clearfil SE Bond after H(3)PO(4) cleansing, and air abrasion combined with Clearfil SE Bond without H(3)PO(4) cleansing. Combinations of surface treatments and bonding procedures were not statistically different. When repair procedure was performed 24 hours after composite polymerization, different combinations of surface treatments and bonding procedures affected repair bond strength similarly. There was no statistical difference between the repair bond strength of groups air-abraded and bonded with the self-etching system and composite UTS. Only air abrasion associated with a self-etching system provided repair bond strength comparable to composite UTS.

  8. Surface Modification Counteracts Adverse Effects Associated with Immobilization after Flexor Tendon Repair

    OpenAIRE

    2012-01-01

    Although post-rehabilitation is routinely performed following flexor tendon repair, in some clinical scenarios post-rehabilitation must be delayed. We investigated modification of the tendon surface using carbodiimide derivatized hyaluronic acid and lubricin (cd-HA-Lub) to maintain gliding function following flexor tendon repair with postoperative immobilization in a in vivo canine model. Flexor digitorum profundus tendons from the 2nd and 5th digits of one forepaw of six dogs were transected...

  9. Autophagy modulates articular cartilage vesicle formation in primary articular chondrocytes.

    Science.gov (United States)

    Rosenthal, Ann K; Gohr, Claudia M; Mitton-Fitzgerald, Elizabeth; Grewal, Rupinder; Ninomiya, James; Coyne, Carolyn B; Jackson, William T

    2015-05-22

    Chondrocyte-derived extracellular organelles known as articular cartilage vesicles (ACVs) participate in non-classical protein secretion, intercellular communication, and pathologic calcification. Factors affecting ACV formation and release remain poorly characterized; although in some cell types, the generation of extracellular vesicles is associated with up-regulation of autophagy. We sought to determine the role of autophagy in ACV production by primary articular chondrocytes. Using an innovative dynamic model with a light scatter nanoparticle counting apparatus, we determined the effects of autophagy modulators on ACV number and content in conditioned medium from normal adult porcine and human osteoarthritic chondrocytes. Healthy articular chondrocytes release ACVs into conditioned medium and show significant levels of ongoing autophagy. Rapamycin, which promotes autophagy, increased ACV numbers in a dose- and time-dependent manner associated with increased levels of autophagy markers and autophagosome formation. These effects were suppressed by pharmacologic autophagy inhibitors and short interfering RNA for ATG5. Caspase-3 inhibition and a Rho/ROCK inhibitor prevented rapamycin-induced increases in ACV number. Osteoarthritic chondrocytes, which are deficient in autophagy, did not increase ACV number in response to rapamycin. SMER28, which induces autophagy via an mTOR-independent mechanism, also increased ACV number. ACVs induced under all conditions had similar ecto-enzyme specific activities and types of RNA, and all ACVs contained LC3, an autophagosome-resident protein. These findings identify autophagy as a critical participant in ACV formation, and augment our understanding of ACVs in cartilage disease and repair.

  10. Effect of surface roughness and adhesive system on repair potential of silorane-based resin composite

    Directory of Open Access Journals (Sweden)

    Enas H. Mobarak

    2012-07-01

    Full Text Available This study was performed to evaluate the influence of surface roughness and adhesive system on the repair strength of silorane-based resin composite. Twenty-four substrate discs from silorane-based FiltekP90 were made and stored for 24 h. Half of the discs were roughened against 320 grit SiC paper while the other half was polished against 4000 grit SiC paper. All discs were etched with phosphoric acid. Repair resin composite, FiltekP90 or FiltekZ250, was bonded to the treated surfaces using their corresponding adhesive; P90 System Adhesive (SA or Adper Scotchbond Multipurpose (SBMP ending up with four repair groups. The groups were as follows: G1: Smooth + SA + FiltekP90; G2: Roughened + SA + FiltekP90; G3: Smooth + SBMP + FiltekZ250; G4: Roughened + SBMP + FiltekZ250. Additional six unrepaired discs from each resin composite (G5 and G6 were prepared to test the cohesive strength. After 24 h, discs (n = 6/group were serially sectioned to obtain sticks (n = 30/group for microtensile bond strength (μTBS testing. Scanning electron microscopic (SEM evaluation of substrates that received different treatments as well as representative substrate-repair sticks from each group were performed. Modes of failure were also determined. Two-way ANOVA with Repeated-Measures revealed that surface treatment and repair material had no significant effect on repair bond strength of silorane-based composite material. Paired t-test showed that all repair strength values were significantly lower than the cohesive strength of FiltekP90. Adhesive failure was the predominant mode of failure which was confirmed by SEM. Surface treated FiltekP90 composite showed different textures under SEM whereas phosphoric acid did not produce clear changes. An interaction layer between SBMP adhesive and FiltekZ250 repairing composite was detected. Repair of the silorane composite was successful irrespective of the surface roughness and chemistry of the repair

  11. The Effects of Surface Properties of Nanostructured Bone Repair Materials on Their Performances

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2015-01-01

    Full Text Available Nanotechnology has been expected to be an extraordinarily promising method for bone repair. Meanwhile, the promise of nanobiomaterials for therapeutic applications has been widely reported, and a lot of studies have been made in terms of repairing bone using nanomaterials accompanied by rapid development of nanotechnology. Compared with conventional biomaterials, nanostructured implants have been shown to possess positive effects on cellular functions because of their unique surface properties, such as nanotopography, increased wettability, larger surface area, and microenvironment similar to extracellular matrix. Moreover, many positive cellular responses have been found to take place at the interface between nanostructured implants and host bone. In this paper, we will give a review about the effects of surface properties of nanostructured bone repair materials on their performances in terms of several aspects and a detailed interpretation or introduction on the specific cellular recognitions at the interface between nanostructured implants and host bone.

  12. Biomaterial composite scaffolds in repair of sports-induced articular cartilage defects%生物材料复合支架与运动性关节软骨缺损的修复

    Institute of Scientific and Technical Information of China (English)

    王宏亮; 韩东

    2011-01-01

    目的:探讨复合支架的组织工程学特性及其修复关节软骨缺损的性能评价.方法:以"关节软骨、生物材料、工程软骨、复合材料、复合支架"为中文关键词,以" tissue enginneering,articular cartilage,scaffold material"为英文关键词,采用计算机检索中国期刊全文数据库、PubMed数据库(1993-01/2010-11)相关文章.纳入复合支架材料-细胞复合物修复关节软骨损伤相关的文章,排除重复研究或Meta分析类文章.结果:共入选18篇文章进入结果分析.复合支架是当前软骨组织工程中应用较多的支架,它是将具有互补特征的生物相容性可降解支架,按一定比例和方式组合,设计出结构与性能优化的复合支架.较单一支架材料具有显著优越性,具有更好的生物相容性和一定强度的韧性,较好的孔隙和机械强度.复合支架的制备不仅包括同一类生物材料的复合,还包括不同类别生物材料之间的交叉复合.可分为纯天然支架材料、纯人工支架材料以及天然与人工支架材料的复合等3类.结论:复合支架使生物材料具有互补特性,一定程度上满足了理想生物支架材料应具有的综合特点,但目前很多研究仍处于实验阶段,还有一些问题有待于解决,如不同材料的复合比例、复合工艺等.%OBJECTIVE: To investigate the tissue engineering properties of the composite scaffold and its performance evaluation for the repair of articular cartilage defects.METHODS: Using "articular cartilage, biological materials, engineering cartilage, composite materials, composite scaffold" in Chinese and "tissue engineering, articular cartilage, scaffold material" in English as the key words, a computer-based online search of China Academic Journal Full-text database and PubMed database (1993-01/2010-11) was performed. Articles about the composite scaffold-cell compound in the repair of articular cartilage injury, duplicated research or Meta

  13. Tissue engineering technology and biomaterials for repair of sports articular cartilage injury%组织工程技术及生物材料修复运动性关节软骨损伤

    Institute of Scientific and Technical Information of China (English)

    马金玉; 薛媛; 杨洪武

    2011-01-01

    January 1993 to October 2010 was performed for related articles, using "articular cartilage, tissue engineering technology, biomaterials" for the Chinese key words and "tissue engineering, articular cartilage, scaffold material" for the English key words, duplicated research or Meta analysis were eliminated. Twenty-three papers mainly discuss seed cells,scaffolds, cytokines and their properties in the repair of sports articular cartilage injury.RESULTS : Totally 104 studies were screened out by computer search, according to inclusion and exclusion criteria, studies regarding the seed cells and bio-scaffolds for cartilage tissue engineering, as well as cytokines for tissue engineering were summarized and analyzed. Seed cells are the primary factor restricting clinical application of tissue engineered cartilage, the common seed cells include cartilage cells, bone marrow stromal stem cells and embryonic stem cells; bio-scaffold materials includes natural materials and synthetic biodegradable polymers; the growth factors for cartilage tissue engineering include transforming growth factor, bone morphogenetic protein, fibroblast growth factor, insulin-like growth factor and so on.CONCLUSION: So far, there is no ideal materials for the seed cells and scaffold materials of engineered cartilage, as well as culture environment, the focus of future research is a kind of tissue engineered articular cartilage with good performance.However, many studies are still in the experimental stage, and some problems need to be solved, especially after tissue engineering scaffolds are implanted, whether the material degradation is synchronized with cell functioning, thus altering genetic materials, gene expression or gene mutation, their clinical application requires relevant scholars and experts to constantly practice and explore.

  14. 自体脂肪源性间充质干细胞修复兔软骨缺损的实验研究%Repair of articular cartilage defects by autologous adipose derived mesenchymal stem cell experiment with rabbits

    Institute of Scientific and Technical Information of China (English)

    杨雨润; 田华

    2008-01-01

    Objective To evaluate the effectiveness of autologous adipose derived mesenchymal stem cells (ADSCs) tranduced by adenovirus-mediated human transforming growth factor 2 (Ad-hTGF-β2) gene in the repair of articular cartilage defects. Methods Rabbit ADSCs were obtained, cultured, and transfected with Ad-hTGF-β2 containing human transforming growth factor (hTGF) - β2. Three days later RT-PCR was used to detect the mRNA expression of hTGF- β2 in the ADSCs, and ELISA was used to detect the protein expression of hTGF-β2 in the supernatant, phosphorylation of Smad was examined by Western blotting. Articular cartilage defects at the femoral trochlea were made on 20 rabbits (40 sides) so as to establish animal models. The culture-expanded rabbit ADSCs transfected with Ad-hTGF- 2 were seeded on poly (L-lactic-co-glycolic acid) (PLGA) scaffolds. The cell-adhered PLGA scaffolds were implanted into the articular cartilage defects. Plain PLGA was implanted into the left-side defects of 10 rabbits as control group and the defects of 10 sides remained untreated as blank control group. The rabbits were sacrificed 4, 12, and 24 weeks after the operation respectively. The specimens of defects were examined histologically and stained immunohistochemically for type Ⅱ collagen. Results After transfection the ADSCs expressed mRNA and protein expression of hTGF- β2 and Western blotting showed bands of phosphorylated Smad. The cartilage specimens harvested from the experimental group rabbits demonstrated hyaline cartilage formation mingled closely with the nearby tissues and expression of type Ⅱ collagen. However, only fibroblasts, not cartilage-like cells, were seen in the control groups that lacked the expression of type Ⅱ collagen too. Conclusion Culture-expanded autologous ADSCs adhered with PLGA composites facilitate the formation of hyaline-cartilage.%目的 评价腺病毒介导的人转化生长因子β2(Ad-hTGF-β2)基因转染自体兔脂肪间充质干细胞(ADSCs)

  15. 应用生物蛋白胶与胚胎软骨细胞混合移植修复兔膝关节实验性软骨缺损区%Repair of experimental defects of articular cartilage in rabbits with homografts of fibrin sealant and embryonic chondrocytes

    Institute of Scientific and Technical Information of China (English)

    陆敏安; 杨渊; 肖增明; 李世德

    2005-01-01

    BACKGROUND:Research about the repair of articular cartilage with heterograft chondrocytes is frequently reported, but the method may cause immune rejection. Since the embryonic cells possess lower antigenicity and stronger proliferation capability, it is hoped that they can be used as a novel carrier substitute in tissue engineering research.DESIGN: A randomized grouping observation and comparative experiment.SETTING: Histological Embryonic Laboratory in Guangxi Medical University.MATERIALS: A big white adult New Zealand rabbit pregnant for 4 weeks was adopted; and another 24 big white adult New Zealand rabbits were selected, with no limitationin whether they were female or male and with a body mass of 2 to 2.5 kg.METHODS: This experiment was carried out at the Histological Embryonic Laboratory in Guangxi Medical University between December 2000and June 2002. The models of defects in articular cartilage were made artificially in femur medial malleolus of the mature rabbits. In the experimental group, defects were repaired by the implantation of Fibrin Sealant and embryonic chondrocytes mixture, but for the control group, only Fibrin Sealant was implanted or nothing was done about the defect. The restoration of articular cartilage defect was then observed 4,8 and 12 weeks after the operation, and was scored according to modified Pineda's method. The standard consists of 5 items, I.e., cellular morphology, matrix staining, surfacing smoothness, cartilage thickness and host union. 0 refers to normal and the higher the score is, the more serious the pathological changes are.MAIN OUTCOME MEASURES: ①The general observation of rabbit knee joint; ② Histological observation of rabbit knee joints; ③ Histological semi-quantitative score of articular cartilage; ④ Appraisal of the curative effect of articular cartilage defects.RESULTS: Totally 24 rabbits were enrolled in this experiment and all entered the stage of result analysis. ① The general observation of rabbit

  16. Different surface preparation techniques of porcelain repaired with composite resin and fracture resistance

    Directory of Open Access Journals (Sweden)

    Mohd Helmy Khalid Abd Wahab

    2011-01-01

    Full Text Available Background : Porcelain from prosthesis such as crown or bridge can be fractured if exposed to trauma; and, can be repaired at chairside using composite resin. Aim : To investigate the fracture resistance of few techniques of surface preparation in repairing fractured porcelain using composite resin. Materials and Methods : Eighty samples of porcelain blocks were divided into 4 groups for different surface preparations, such as, Cimara repairing kit; porcelain etch kit containing hydrofluoric acid; Panavia F resin cement; and, sandblasting using aluminium oxide, before composite resin (Filtek Z250, 3M ESPE was bonded to the prepared porcelain blocks. Twenty others samples in the control group comprised of pure porcelain blocks. The fracture resistance of each sample was tested using Instron machine (UK. Results : With the exception of the group repaired using hydrofluoric acid (3.04±1.04 Mpa, all the other groups showed significant difference in the fracture resistance values when compared to the control group (3.05 ± 1.42 MPa at P<0.05. Conclusions : Etching of the porcelain blocks with hydrofluoric acid holds promise in the repair of fractured porcelain with composite resin at chairside.

  17. Surface roughness of etched composite resin in light of composite repair

    NARCIS (Netherlands)

    Loomans, B.A.C.; Cardoso, M.V.; Opdam, N.J.M.; Roeters, F.J.M.; Munck, J. De; Huysmans, M.C.D.N.J.M.; Meerbeek, B. Van

    2011-01-01

    OBJECTIVES: In search for clinically effective composite repair protocols, the effect of various etching protocols on the surface roughness of composite resins with different filler composition were investigated. METHODS: Of two composite resins (hybrid-filled Clearfil AP-X; nano-filled Filtek Supre

  18. Bond strength durability of direct and indirect composite systems following surface conditioning for repair

    NARCIS (Netherlands)

    Passos, Sheila Pestana; Ozcan, Mutlu; Vanderlei, Aleska Dias; Leite, Fabiola Pessoa Pereira; Kimpara, Estevao Tomomitsu; Bottino, Marco Antonio

    2007-01-01

    Purpose: This study evaluated the effect of surface conditioning methods and thermocycling on the bond strength between a resin composite and an indirect composite system in order to test the repair bond strength. Materials and Methods: Eighteen blocks (5 x 5 x 4 mm) of indirect resin composite (Sin

  19. 75 FR 80219 - National Emission Standards for Shipbuilding and Ship Repair (Surface Coating); National Emission...

    Science.gov (United States)

    2010-12-21

    ... \\1\\ OAQPS Contact \\2\\ Shipbuilding and Ship Repair Mr. Leonard Lazarus, Ms. J. Kaye (Surface Coating). (202) 564-6369, Whitfield, (919) lazarus.leonard@epa 541-2509, .gov. whitfield.kaye@epa.gov Wood Furniture Manufacturing Mr. Leonard Lazarus, Ms. J. Kaye Operations. (202) 564-6369, Whitfield,...

  20. Intra-articular Loose Body with Concomitant Bankart Lesion after a Traumatic Shoulder Dislocation: A Case Report.

    Science.gov (United States)

    Lim, Jason B T; Tan, Andrew H C

    2017-01-01

    The spectrum of pathoanatomic lesions encountered in anterior shoulder dislocation is broad. There could be a presence of loose bodies, chondral and osteochondral, in the shoulder joint and also concomitant rotator cuff partial tears resulting from acute and chronic shoulder instability. We present one case report of a 46-year-old male Chinese with an uncommon case of Bankart lesion, with a full thickness chondral defect over the superior glenoid articular surface manifesting as a large intra-articular loose cartilaginous body. The patient presented with persistent shoulder pain with signs of shoulder instability. He underwent arthroscopic repair of his Bankart lesion with the removal of intra-articular loose body. We aim to discuss the diagnosis, radiological imaging, as well as, arthroscopic treatment of loose body in the glenohumeral joint due to anterior shoulder dislocation in our report. In our case report, we highlight the importance to identify other associated injuries from the history and examination after an episode of traumatic anterior shoulder dislocation. Arthroscopic treatment is a useful minimally invasive option to remove the large fragment of intra-articular loose body and also repair the Bankart lesion in the same setting. Both of these lesions must be treated as they are crucial for pain relief, as well as stabilizing the shoulder, to prevent further episodes of dislocation.

  1. Acute and chronic response of articular cartilage to Ho:YAG laser irradiation

    Science.gov (United States)

    Trauner, Kenneth B.; Nishioka, Norman S.; Flotte, Thomas J.; Patel, Dinesh K.

    1992-06-01

    A Ho:YAG laser system operating at a wavelength of 2.1 microns has recently been introduced for use in arthroscopic surgery. The acceptability of this new tool will be determined not only by its ability to resect tissue, but also by its long term effects on articular surfaces. In order to investigate these issues further, we performed two studies to evaluate the acute and chronic effects of the laser on cartilaginous tissue. We evaluated the acute, in vitro effects of 2.1 micron laser irradiation on articular and fibrocartilage. This included the measurement of ablation efficiency, ablation threshold and thermal damage in both meniscus and articular cartilage. To document the chronic effects on articular cartilage in vivo, we next performed a ten week healing study. Eight sheep weighing 30 - 40 kg underwent bilateral arthrotomy procedures. Multiple full thickness and partial thickness defects were created. Animals were sacrificed at 0, 2, 4, and 10 weeks. The healing study demonstrated: (1) no healing of full or partial thickness defects at 10 weeks with hyaline cartilage; (2) fibrocartilaginous granulation tissue filling full thickness defects at two and four weeks, but no longer evident at ten weeks; (3) chondrocyte necrosis extending to greater than 900 microns distal to ablation craters at four weeks with no evidence of repair at later dates; and (4) chondrocyte hyperplasia at the borders of the damage zone at two weeks but no longer evident at later sacrifice dates.

  2. Repair Bond Strength of Aged Resin Composite after Different Surface and Bonding Treatments

    Directory of Open Access Journals (Sweden)

    Michael Wendler

    2016-07-01

    Full Text Available The aim of this study was to compare the effect of different mechanical surface treatments and chemical bonding protocols on the tensile bond strength (TBS of aged composite. Bar specimens were produced using a nanohybrid resin composite and aged in distilled water for 30 days. Different surface treatments (diamond bur, phosphoric acid, silane, and sandblasting with Al2O3 or CoJet Sand, as well as bonding protocols (Primer/Adhesive were used prior to application of the repair composite. TBS of the specimens was measured and the results were analyzed using analysis of variance (ANOVA and the Student–Newman–Keuls test (α = 0.05. Mechanically treated surfaces were characterized under SEM and by profilometry. The effect of water aging on the degree of conversion was measured by means of FTIR-ATR spectroscopy. An important increase in the degree of conversion was observed after aging. No significant differences in TBS were observed among the mechanical surface treatments, despite variations in surface roughness profiles. Phosphoric acid etching significantly improved repair bond strength values. The cohesive TBS of the material was only reached using resin bonding agents. Application of an intermediate bonding system plays a key role in achieving reliable repair bond strengths, whereas the kind of mechanical surface treatment appears to play a secondary role.

  3. Repair Bond Strength of Aged Resin Composite after Different Surface and Bonding Treatments

    Science.gov (United States)

    Wendler, Michael; Belli, Renan; Panzer, Reinhard; Skibbe, Daniel; Petschelt, Anselm; Lohbauer, Ulrich

    2016-01-01

    The aim of this study was to compare the effect of different mechanical surface treatments and chemical bonding protocols on the tensile bond strength (TBS) of aged composite. Bar specimens were produced using a nanohybrid resin composite and aged in distilled water for 30 days. Different surface treatments (diamond bur, phosphoric acid, silane, and sandblasting with Al2O3 or CoJet Sand), as well as bonding protocols (Primer/Adhesive) were used prior to application of the repair composite. TBS of the specimens was measured and the results were analyzed using analysis of variance (ANOVA) and the Student–Newman–Keuls test (α = 0.05). Mechanically treated surfaces were characterized under SEM and by profilometry. The effect of water aging on the degree of conversion was measured by means of FTIR-ATR spectroscopy. An important increase in the degree of conversion was observed after aging. No significant differences in TBS were observed among the mechanical surface treatments, despite variations in surface roughness profiles. Phosphoric acid etching significantly improved repair bond strength values. The cohesive TBS of the material was only reached using resin bonding agents. Application of an intermediate bonding system plays a key role in achieving reliable repair bond strengths, whereas the kind of mechanical surface treatment appears to play a secondary role. PMID:28773669

  4. Bone development and its relation to fracture repair. The role of mesenchymal osteoblasts and surface osteoblasts

    Directory of Open Access Journals (Sweden)

    F Shapiro

    2008-04-01

    Full Text Available Bone development occurs by two mechanisms: intramembranous bone formation and endochondral bone formation. Bone tissue forms by eventual differentiation of osteoprogenitor cells into either mesenchymal osteoblasts (MOBL, which synthesize woven bone in random orientation, or surface osteoblasts (SOBL, which synthesize bone on surfaces in a well oriented lamellar array. Bone repair uses the same formation patterns as bone development but the specific mechanism of repair is determined by the biomechanical environment provided. Bone synthesis and maintenance are highly dependent on the blood supply of bone and on cell-cell communication via the lacunar-canalicular system. Recent investigations highlight the molecular cascades leading to cell differentiation, the components of the structural proteins such as the various collagens, and tissue vascularization. The patterning of bone matrix from an initial woven to an eventual lamellar orientation is essential for bone to develop its maximum strength. This review demonstrates the repetitive nature of woven to lamellar bone formation as mediated by MOBLs and SOBLs in both normal vertebrate bones and bone repair. Repair, using endochondral, primary, direct and distraction osteogenesis mechanisms, is reviewed along with the associated molecular, vascular, and biophysical features.

  5. Lubricin Surface Modification Improves Tendon Gliding After Tendon Repair in a Canine Model in Vitro

    Science.gov (United States)

    Taguchi, Manabu; Sun, Yu-Long; Zhao, Chunfeng; Zobitz, Mark E.; Cha, Chung-Ja; Jay, Gregory D.; An, Kai-Nan; Amadio, Peter C.

    2011-01-01

    This study investigated the effects of lubricin on the gliding of repaired flexor digitorum profundus (FDP) tendons in vitro. Canine FDP tendons were completely lacerated, repaired with a modified Pennington technique, and treated with one of the following solutions: saline, carbodiimide derivatized gelatin/hyaluronic acid (cd-HA-gelatin), carbodiimide derivatized gelatin to which lubricin was added in a second step (cd-gelatin + lubricin), or carbodiimide derivatized gelatin/HA + lubricin (cd-HA-gelatin + lubricin). After treatment, gliding resistance was measured up to 1,000 cycles of simulated flexion/extension motion. The increase in average and peak gliding resistance in cd-HA-gelatin, cd-gelatin + lubricin, and cd-HA-gelatin + lubricin tendons was less than the control tendons after 1,000 cycles (p < 0.05). The increase in average gliding resistance of cd-HA-gelatin + lubricin treated tendons was also less than that of the cd-HA-gelatin treated tendons (p < 0.05). The surfaces of the repaired tendons and associated pulleys were assessed qualitatively with scanning electron microscopy and appeared smooth after 1,000 cycles of tendon motion for the cd-HA-gelatin, cd-gelatin + lubricin, and cd-HA-gelatin + lubricin treated tendons, while that of the saline control appeared roughened. These results suggest that tendon surface modification can improve tendon gliding ability, with a trend suggesting that lubricin fixed on the repaired tendon may provide additional improvement over that provided by HA and gelatin alone. PMID:18683890

  6. Influence of surface treatments to repair recent fillings of silorane-and methacrylate-based composites.

    Science.gov (United States)

    Kaneko, Marina; Caldas, Ricardo Armini; Feitosa, Victor Pinheiro; Xediek Consani, Rafael Leonardo; Schneider, Luis Felipe J; Bacchi, Ataís

    2015-01-01

    The aim of this study was to evaluate the tensile bond strength (TBS) of repairs in recent fillings of methacrylate- (MBC) or silorane-based composites (SBC) subsequent to different surface treatments. Fifty slabs of Filtek P60 (3M ESPE, St Paul, USA) and Filtek P90 (3M ESPE) were stored for 10 days in distilled water at 37°C. The surface of adhesion was abraded with a 600-grit silicone paper and repaired using each respective composite: G1, no treatment (control); G2, application of adhesive; G3, application of silane and adhesive; G4, sandblasting (Al2O3) and adhesive; and G5, sandblasting (Al2O3), silane, and adhesive. Further 10 slabs of each composite were also evaluated for cohesive strength (G6). After 30 days immersion in distilled water at 37°C, the TBS was determined. TBS results were higher for MBC than for SBC (P = 0.00012). The experimental groups were similar for SBC and the TBS was 27% of its cohesive strength. For P60, sandblasting significantly improved the TBS compared to other groups. With MBC, G4 and G5, the TBS was approximately 47% of its cohesive strength. Sandblasting (Al2O3) improves the repair-strength of MBC, whilst for the SBC all treatments succeed. MBC presents higher repair strength than SBC.

  7. Effect of Various Surface Treatment on Repair Strength of Composite Resin

    Directory of Open Access Journals (Sweden)

    Y. Alizade

    2004-12-01

    Full Text Available Statement of Problem: In some clinical situations, repair of composite restorations is treatment of choice. Improving the bond strength between one new and old composite usually requires increased surface roughness to promote mechanical interlocking sincechemical bonding might not be adequate. Similarly, the treatment of a laboratory fabricated resin composite restoration involves the same procedures, and there is a need to create the strongest possible bond of a resin cement to a previously polymerized composite.Purpose: The aim of this study was to evaluate the effect of various surface treatments on the shear bond strength of repaired to aged composite resin.Materials and Methods: Eighty four cylindrical specimens of a composite resin were fabricated and stored in distilled water for 100 days prior to surface treatment. Surface treatment of old composite was done in 6 groups as follow:1- Air abrasion with CoJet sand particles with micoretcher + silane + dentin bonding agent2- Air abrasion with 50μm Al2O3 particles+ phosphoric acid+ silane+ dentin bonding agent3- Air abrasion with 50μm Al2O3 particles + phosphoric acid + dentin bonding agent4- Diamond bur + phosphoric acid + silane + dentin bonding agent5- Diamond bur + phosphoric acid + dentin bonding agent6- Diamond bur + phosphoric acid + composite activator + dentin bonding agentThen fresh composite resin was bonded to treated surfaces. Twelve specimens were also fabricated as control group with the same diameter but with the height twice as much as other specimens. All of the specimens were thermocycled prior to testing for shear bondstrength. The bond strength data were analyzed statistically using one way ANOVA test, t test and Duncan's grouping test.Results: One-way ANOVA indicated no significant difference between 7 groups (P=0.059. One-way ANOVA indicated significant difference between the three diamond bur groups (P=0.036. Silane had a significant effect on the repair bond

  8. O centro instantâneo de movimento e vetor velocidade em joelhos submetidos a incisuroplastia troclear e estabilização articular após transecção do ligamento cruzado cranial em cães Instantaneous center of motion and velocity vector in stifle of dogs undergoing intercondylar notchplasty and articular repair following transection of the cranial cruciate ligament

    Directory of Open Access Journals (Sweden)

    André Luis Selmi

    2007-06-01

    which a subgroup of three dogs were euthanatized. The ICM and resulting Vv were determined by radiographic examination of the stifle. All the stifles presented normally positioned ICM and Vv before surgery. No changes were observed in ICM or Vv in all stifles following intra-articular repair, in association or not with IN, throughout the evaluation period, despite the fact that three dogs in GC and two in GI presented a positive cranial drawer sign immediately following surgery, two dogs in GC and GI at 30 days po, and one single dog in each group thereafter until 180 days po. It is concluded that articular repair, in association with IN or not, did not alter stifle biomechanics, in respect to ICM and Vv.

  9. Probing the molecular structures of plasma-damaged and surface-repaired low-k dielectrics.

    Science.gov (United States)

    Zhang, Xiaoxian; Myers, John N; Lin, Qinghuang; Bielefeld, Jeffery D; Chen, Zhan

    2015-10-21

    Fully understanding the effect and the molecular mechanisms of plasma damage and silylation repair on low dielectric constant (low-k) materials is essential to the design of low-k dielectrics with defined properties and the integration of low-k dielectrics into advanced interconnects of modern electronics. Here, analytical techniques including sum frequency generation vibrational spectroscopy (SFG), Fourier transform infrared spectroscopy (FTIR), contact angle goniometry (CA) and X-ray photoelectron spectroscopy (XPS) have been employed to provide a comprehensive characterization of the surface and bulk structure changes of poly(methyl)silsesquioxane (PMSQ) low-k thin films before and after O2 plasma treatment and silylation repair. O2 plasma treatment altered drastically both the molecular structures and water structures at the surfaces of the PMSQ film while no bulk structural change was detected. For example, ∼34% Si-CH3 groups were removed from the PMSQ surface, and the Si-CH3 groups at the film surface tilted toward the surface after the O2 plasma treatment. The oxidation by the O2 plasma made the PMSQ film surface more hydrophilic and thus enhanced the water adsorption at the film surface. Both strongly and weakly hydrogen bonded water were detected at the plasma-damaged film surface during exposure to water with the former being the dominate component. It is postulated that this enhancement of both chemisorbed and physisorbed water after the O2 plasma treatment leads to the degradation of low-k properties and reliability. The degradation of the PMSQ low-k film can be recovered by repairing the plasma-damaged surface using a silylation reaction. The silylation method, however, cannot fully recover the plasma induced damage at the PMSQ film surface as evidenced by the existence of hydrophilic groups, including C-O/C[double bond, length as m-dash]O and residual Si-OH groups. This work provides a molecular level picture on the surface structural changes of low

  10. Risks relating to posterior 2-portal arthroscopic subtalar arthrodesis and articular surfaces abrasion quality achievable with these approaches: a cadaver study.

    Science.gov (United States)

    Mouilhade, F; Oger, P; Roussignol, X; Boisrenoult, P; Sfez, J; Duparc, F

    2011-06-01

    Many techniques for arthroscopic subtalar arthrodesis have been described since 1985. The procedure can be challenging because posterior and anterior portals are used conjointly with distraction. A posterior 2-portal approach was described in 2000. The goal of this study was to evaluate the quality of the freshening that can be achieved in the posterior subtalar joint using this approach. Does a posterior 2-portal approach allow for a complete freshening of the posterior subtalar joint? Freshening was performed through an arthroscopic posterior 2-portal approach on 10 cadavers. The quality of bone freshening and proximity of the neurovascular structures to the posterior portals were subsequently evaluated by dissection. There was one partial laceration of the sural nerve. The posteromedial portal was 6.8mm (95% CI: 4.4 to 9.2) away from the posterior tibial vascular pedicle. The entire talar and calcaneal articular surfaces of the posterior subtalar joint were freshened. In eight of 10 cases (95% CI: 48 to 95%), the posteromedial process of the talus prevented contact between fragments. This study showed that the entire posterior subtalar joint can be freshened through an arthroscopic posterior 2-portal approach with little morbidity. Level IV. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  11. Mechanical loading of knee articular cartilage induced by muscle contraction can be assessed by measuring electrical potentials at the surface of the knee.

    Science.gov (United States)

    Zhu, Lin; Buschmann, Michael D; Savard, Pierre

    2016-02-01

    Electroarthrography (EAG) consists of recording electrical potentials on the knee surface that originate from streaming potentials within articular cartilage while the joint is undergoing compressive loading. The aim was to investigate how the contraction of specific leg muscles affects the contact force of the knee joint and, in turn, the EAG values. For six normal subjects, voluntary isometric muscle contractions were repeatedly conducted to activate four leg muscle groups while the subject was lying on his back. Two EAG signals were recorded on the medial and lateral sides of the knee, as well as four EMG signals (gastrocnemius, hamstring, quadriceps, tensor fascia latae), and the signal from a force plate fixed against the foot according to the direction of the force. The EAG and force signals were very well correlated: the median of the correlation coefficients between an EAG signal and the corresponding force signal during each loading cycle was 0.91, and 86% of the correlation coefficients were statistically significant (pmuscle contraction was possible for the gastrocnemius and hamstring, but not always for the quadriceps and tensor fascia latae. Using the clinical loading protocol which consists of a one-legged stance, the quadriceps and hamstring EMGs showed minimal activity; loading cycles with increased EAG amplitude were associated with higher EMG activity from the gastrocnemius, which is involved in antero-posterior balance. These results document the role of the EAG as a "sensor" of the knee contact force and contribute to the development of clinical loading protocols with improved reproducibility.

  12. Effects of intra-articular injection of mesenchymal stem cells associated with platelet-rich plasma in a rabbit model of osteoarthritis.

    Science.gov (United States)

    Hermeto, L C; DeRossi, R; Oliveira, R J; Pesarini, J R; Antoniolli-Silva, A C M B; Jardim, P H A; Santana, A E; Deffune, E; Rinaldi, J C; Justulin, L A

    2016-09-02

    The current study aims to evaluate the macroscopic and histological effects of autologous mesenchymal stem cells (MSC) and platelet-rich plasma on knee articular cartilage regeneration in an experimental model of osteoarthritis. Twenty-four rabbits were randomly divided into four groups: control group, platelet-rich plasma group, autologous MSC undifferentiated group, and autologous MSC differentiated into chondrocyte group. Collagenase solution was used to induce osteoarthritis, and treatments were applied to each group at 6 weeks following osteoarthritis induction. After 60 days of therapy, the animals were euthanized and the articular surfaces were subjected to macroscopic and histological evaluations. The adipogenic, chondrogenic, and osteogenic differentiation potentials of MSCs were evaluated. Macroscopic and histological examinations revealed improved tissue repair in the MSC-treated groups. However, no difference was found between MSC-differentiated and undifferentiated chondrocytes. We found that MSCs derived from adipose tissue and platelet-rich plasma were associated with beneficial effects in articular cartilage regeneration during experimental osteoarthritis.

  13. A scaffold-enhanced light-activated surgical adhesive technique: surface selection for enhanced tensile strength in wound repair

    Science.gov (United States)

    Soller, Eric C.; Hoffman, Grant T.; Heintzelman, Douglas L.; Duffy, Mark T.; Bloom, Jeffrey N.; McNally-Heintzelman, Karen M.

    2004-07-01

    An ex vivo study was conducted to determine the effect of the irregularity of the scaffold surface on the tensile strength of repairs formed using our Scaffold-Enhanced Biological Adhesive (SEBA). Two different scaffold materials were investigated: (i) a synthetic biodegradable material fabricated from poly(L-lactic-co-glycolic acid); and (ii) a biological material, small intestinal submucosa, manufactured by Cook BioTech. The scaffolds were doped with protein solder composed of 50%(w/v) bovine serum albumin solder and 0.5mg/ml indocyanine green dye mixed in deionized water, and activated with an 808-nm diode laser. The tensile strength of repairs performed on bovine thoracic aorta, liver, spleen, small intestine and lung, using the smooth and irregular surfaces of the above scaffold-enhanced materials were measured and the time-to-failure was recorded. The tensile strength of repairs formed using the irregular surfaces of the scaffolds were consistently higher than those formed using the smooth surfaces of the scaffolds. The largest difference was observed on repairs formed on the aorta and small intestine, where the repairs were, on average, 50% stronger using the irregular versus the smooth scaffold surfaces. In addition, the time-to-failure of repairs formed using the irregular surfaces of the scaffolds were between 50% and 100% longer than that achieved using the smooth surfaces of the scaffolds. It has previously been shown that distributing or dispersing the adhesive forces over the increased surface area of the scaffold, either smooth or irregular, produces stronger repairs than albumin solder alone. The increase in the absolute strength and longevity of repairs seen in this new study when the irregular surfaces of the scaffolds are used is thought to be due to the distribution of forces between the many independent micro-adhesions provided by the irregular surfaces.

  14. Tensorial electrokinetics in articular cartilage.

    Science.gov (United States)

    Reynaud, Boris; Quinn, Thomas M

    2006-09-15

    Electrokinetic phenomena contribute to biomechanical functions of articular cartilage and underlie promising methods for early detection of osteoarthritic lesions. Although some transport properties, such as hydraulic permeability, are known to become anisotropic with compression, the direction-dependence of cartilage electrokinetic properties remains unknown. Electroosmosis experiments were therefore performed on adult bovine articular cartilage samples, whereby fluid flows were driven by electric currents in directions parallel and perpendicular to the articular surface of statically compressed explants. Magnitudes of electrokinetic coefficients decreased slightly with compression (from approximately -7.5 microL/As in the range of 0-20% compression to -6.0 microL/As in the 35-50% range) consistent with predictions of microstructure-based models of cartilage material properties. However, no significant dependence on direction of the electrokinetic coupling coefficient was detected, even for conditions where the hydraulic permeability tensor is known to be anisotropic. This contrast may also be interpreted using microstructure-based models, and provides insights into structure-function relationships in cartilage extracellular matrix and physical mediators of cell responses to tissue compression. Findings support the use of relatively simple isotropic modeling approaches for electrokinetic phenomena in cartilage and related materials, and indicate that measurement of electrokinetic properties may provide particularly robust means for clinical evaluation of cartilage matrix integrity.

  15. Hyaline Articular Matrix Formed by Dynamic Self-Regenerating Cartilage and Hydrogels.

    Science.gov (United States)

    Meppelink, Amanda M; Zhao, Xing; Griffin, Darvin J; Erali, Richard; Gill, Thomas J; Bonassar, Lawrence J; Redmond, Robert W; Randolph, Mark A

    2016-07-01

    Injuries to the articular cartilage surface are challenging to repair because cartilage possesses a limited capacity for self-repair. The outcomes of current clinical procedures aimed to address these injuries are inconsistent and unsatisfactory. We have developed a novel method for generating hyaline articular cartilage to improve the outcome of joint surface repair. A suspension of 10(7) swine chondrocytes was cultured under reciprocating motion for 14 days. The resulting dynamic self-regenerating cartilage (dSRC) was placed in a cartilage ring and capped with fibrin and collagen gel. A control group consisted of chondrocytes encapsulated in fibrin gel. Constructs were implanted subcutaneously in nude mice and harvested after 6 weeks. Gross, histological, immunohistochemical, biochemical, and biomechanical analyses were performed. In swine patellar groove, dSRC was implanted into osteochondral defects capped with collagen gel and compared to defects filled with osteochondral plugs, collagen gel, or left empty after 6 weeks. In mice, the fibrin- and collagen-capped dSRC constructs showed enhanced contiguous cartilage matrix formation over the control of cells encapsulated in fibrin gel. Biochemically, the fibrin and collagen gel dSRC groups were statistically improved in glycosaminoglycan and hydroxyproline content compared to the control. There was no statistical difference in the biomechanical data between the dSRC groups and the control. The swine model also showed contiguous cartilage matrix in the dSRC group but not in the collagen gel and empty defects. These data demonstrate the survivability and successful matrix formation of dSRC under the mechanical forces experienced by normal hyaline cartilage in the knee joint. The results from this study demonstrate that dSRC capped with hydrogels successfully engineers contiguous articular cartilage matrix in both nonload-bearing and load-bearing environments.

  16. Robust and general method for determining surface fluid flow boundary conditions in articular cartilage contact mechanics modeling.

    Science.gov (United States)

    Pawaskar, Sainath Shrikant; Fisher, John; Jin, Zhongmin

    2010-03-01

    Contact detection in cartilage contact mechanics is an important feature of any analytical or computational modeling investigation when the biphasic nature of cartilage and the corresponding tribology are taken into account. The fluid flow boundary conditions will change based on whether the surface is in contact or not, which will affect the interstitial fluid pressurization. This in turn will increase or decrease the load sustained by the fluid phase, with a direct effect on friction, wear, and lubrication. In laboratory experiments or clinical hemiarthroplasty, when a rigid indenter or metallic prosthesis is used to apply load to the cartilage, there will not be any fluid flow normal to the surface in the contact region due to the impermeable nature of the indenter/prosthesis. In the natural joint, on the other hand, where two cartilage surfaces interact, flow will depend on the pressure difference across the interface. Furthermore, in both these cases, the fluid would flow freely in non-contacting regions. However, it should be pointed out that the contact area is generally unknown in advance in both cases and can only be determined as part of the solution. In the present finite element study, a general and robust algorithm was proposed to decide nodes in contact on the cartilage surface and, accordingly, impose the fluid flow boundary conditions. The algorithm was first tested for a rigid indenter against cartilage model. The algorithm worked well for two-dimensional four-noded and eight-noded axisymmetric element models as well as three-dimensional models. It was then extended to include two cartilages in contact. The results were in excellent agreement with the previous studies reported in the literature.

  17. Influence of surface preparation on fracture load of resin composite-based repairs

    Science.gov (United States)

    Mateos-Palacios, Rocío; Román-Rodríguez, Juan-Luis; Solá-Ruíz, María-Fernanda; Fons-Font, Antonio

    2015-01-01

    The purpose of the present study is to evaluate the fracture load of composite-based repairs to fractured zirconium oxide (Z) crowns and to ceramic-fused-to-metal (CM) crowns, comparing different mechanical surface preparation methods. A total of 75 crowns were repaired; samples then underwent dynamic loading and thermocycling. Final fracture load values for failure of the repaired crowns were measured and the type of fracture registered. Group I: CM: Surface preparation with a diamond bur + 9.5% Hydrofluoric Acid (HF) etching; Group II): CM: air-particle (Al2O3) + 9.5% HF; Group III: CM: Silica coating (SiO2); Group IV): Z: air-particle (Al2O3) + HF 9.5%; Group V) Z: Silica coating (SiO2). Of the three CM groups, Group I (CM-diamond bur) showed the highest mean failure value, with significant difference in comparison with Group III (CM-silica coating). For the zirconia groups, the highest value was obtained by Group V (silica coating). Key words:Crown, ceramic-fused-to-metal, zirconia, resin-composite, ceramic covering. PMID:25810848

  18. Influence of surface preparation on fracture load of resin composite-based repairs.

    Science.gov (United States)

    Agustín-Panadero, Rubén; Mateos-Palacios, Rocío; Román-Rodríguez, Juan-Luis; Solá-Ruíz, María-Fernanda; Fons-Font, Antonio

    2015-02-01

    The purpose of the present study is to evaluate the fracture load of composite-based repairs to fractured zirconium oxide (Z) crowns and to ceramic-fused-to-metal (CM) crowns, comparing different mechanical surface preparation methods. A total of 75 crowns were repaired; samples then underwent dynamic loading and thermocycling. Final fracture load values for failure of the repaired crowns were measured and the type of fracture registered. Group I: CM: Surface preparation with a diamond bur + 9.5% Hydrofluoric Acid (HF) etching; Group II): CM: air-particle (Al2O3) + 9.5% HF; Group III: CM: Silica coating (SiO2); Group IV): Z: air-particle (Al2O3) + HF 9.5%; Group V) Z: Silica coating (SiO2). Of the three CM groups, Group I (CM-diamond bur) showed the highest mean failure value, with significant difference in comparison with Group III (CM-silica coating). For the zirconia groups, the highest value was obtained by Group V (silica coating). Key words:Crown, ceramic-fused-to-metal, zirconia, resin-composite, ceramic covering.

  19. 骨形态发生蛋白与碱性成纤维细胞生长因子联合修复软骨缺损的效果评价%Effects of recombinant human bone morphogenetic protein combined with basic fibroblast growth factor on the repair of articular cartilage defects

    Institute of Scientific and Technical Information of China (English)

    朱国华; 蔡建平; 郭翠玲; 廖家新; 刘勇; 罗洪涛; 许国华; 胡红涛

    2012-01-01

    背景:多种细胞生长因子在骨软骨代谢过程中的协同作用越来越受到重视,但目前复合细胞生长因子修复软骨缺损报道较少,且修复效果尚无定论.目的:探讨骨形态发生蛋白和碱性成纤维细胞生长因子联合应用修复关节软骨缺损的效果.方法:24 只日本大耳白兔建立骨软骨缺损模型后随机等分为4 组,对照组缺损处仅填塞明胶海绵,其他3 组在对照组基础上,缺损处分别注射骨形态发生蛋白和碱性成纤维细胞生长因子、骨形态发生蛋白、碱性成纤维细胞生长因子.结果与结论:大体观察显示联合应用2 种细胞因子后,软骨缺损面基本修复但稍不平整,单独使用其中1 种细胞因子缺损面未完全修复,对照组无明显修复.联合应用2 种细胞因子缺损部位软骨细胞数多于其他3 组(P < 0.05),且Ⅱ型胶原免疫组化染色深于其他组.提示联合应用骨形态发生蛋白和碱性成纤维细胞生长因子可以促进关节软骨损伤的修复,疗效优于单独应用骨形态发生蛋白或碱性成纤维细胞生长因子.%BACKGROUND: The synergy of various cell growth factors attracts more and more attention in the course of cartilage metabolism.However, there are few reports of repairing cartilage defects with combined cell growth factors, and the effect remains unknown atpresent.OBJECTIVE: To study the repairing effect of recombinant human bone morphogenetic protein (rhBMP) combined with basicfibroblast growth factor (bFGF) on articular cartilage defects.METHODS: After the model of articular cartilage defects was made, 24 Japan big-eared white rabbits were randomly divided intofour groupsforintervention: rhBMP combined with bFGF (group A), single rhBMP (group B), single bFGF (group C), the fourthgroup was without injection and just filled with gelatin sponge (group D).RESULTS AND CONCLUSION: In general observation, articular cartilage defects were basically repaired but slightly

  20. Condrocalcinose articular familiar Familial articular chondrocalcinosis

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    Mittermayer Barreto Santiago

    2004-08-01

    Full Text Available Condrocalcinose articular familiar é uma condição clínica caracterizada pela deposição de cristais de pirofosfato de cálcio no líquido sinovial e cartilagens articulares levando à artrite. Descrevemos três membros de uma família com condrocalcinose cujo quadro clínico era caracterizado por artrite intermitente em dois e artrite crônica lembrando artrite reumatóide em um. A avaliação radiológica mostrou calcificações em cartilagens de diversas articulações, particularmente de joelhos. A utilização de colchicina foi suficiente para prevenir as crises de artrite em dois pacientes e o paciente com a forma crônica necessitou uso contínuo de antiinflamatórios não-hormonais. Embora aparentemente rara no Brasil, não afastamos a possibilidade desse dado estar subestimado e sugerimos que seja realizada uma avaliação radiológica articular dos familiares de todo paciente com diagnóstico de condrocalcinose esporádica.Familial articular chondrocalcinosis is a disorder characterized by deposition of calcium pyrophosphate dihydrate crystal in synovial fluid and articular cartilage that can cause joint pain and arthritis. We have identified three members of the same family with chondrocalcinosis. The clinical features of the disease were intermittent episodes of arthritis in two patients and polyarthritis resembling rheumatoid arthritis in one member. The radiological evaluation showed calcification in several joints, particularly in cartilages of the knees. Therapy with colchicine was enough to prevent arthritic crisis in two patients and continous NSAID use was necessary to control symptoms in the last one. Familial chondrocalcinosis seems to be rare in Brazil, but we do not exclude the possibility that this figure is underestimated and suggest that in cases of sporadic chondrocalcinosis other members of the family should be fully investigated.

  1. Effects of three surface conditioning techniques on repair bond strength of nanohybrid and nanofilled composites

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    Negin Nassoohi

    2015-01-01

    Full Text Available Background: Repair bond strength of different composite resins has been assessed in few studies. In addition, reports on the efficacy of surface treatments are debated. Therefore, this in vitro study was conducted to evaluate the effect of three surface treatments on two nanocomposites versus a microhybrid composite. Materials and Methods: In this experimental study, 135 composite blocks (45 specimens per composite of microhybrid (Filtek Supreme Z250, 3M ESPE, USA, nanohybrid (Filtek Supreme XT, 3M ESPE, and nanofilled (Filtek Supreme Z350, 3M ESPE were thermocycled (5000 rounds and then surface roughened (except in a control group of 9 specimens of three composite types. Each composite type was divided into three subgroups of surface treatments: (1 Bur abrading and phosphoric acid (PA etching, (2 sandblasting and PA etching, and (3 hydrofluoric etching and silane application (n = 15 × 9, complying with ISO TR11405. Composite blocks were repaired with the same composite type but of a different color. Microtensile bond strength and modes of failure were analyzed statistically using two-way analyses of variance, Tukey and Chi-square tests (α = 0.05. Results: There were significant differences between three composite resins (P < 0.0001 and treatment techniques (P < 0.0001. Their interaction was nonsignificant (P = 0.228. The difference between nanofilled and nanohybrid was not significant. However, the microhybrid composite showed a significantly higher bond strength (Tukey P < 0.05. Sandblasting was significantly superior to the other two methods, which were not different from each other. Conclusion: Within the limitations of this in vitro study, it seems that microhybrid composite might have higher repair strengths than two evaluated nanocomposites. Among the assessed preparation techniques, sandblasting followed by PA etching might produce the highest bond strength.

  2. Effects of three surface conditioning techniques on repair bond strength of nanohybrid and nanofilled composites

    Science.gov (United States)

    Nassoohi, Negin; Kazemi, Haleh; Sadaghiani, Morad; Mansouri, Mona; Rakhshan, Vahid

    2015-01-01

    Background: Repair bond strength of different composite resins has been assessed in few studies. In addition, reports on the efficacy of surface treatments are debated. Therefore, this in vitro study was conducted to evaluate the effect of three surface treatments on two nanocomposites versus a microhybrid composite. Materials and Methods: In this experimental study, 135 composite blocks (45 specimens per composite) of microhybrid (Filtek Supreme Z250, 3M ESPE, USA), nanohybrid (Filtek Supreme XT, 3M ESPE), and nanofilled (Filtek Supreme Z350, 3M ESPE) were thermocycled (5000 rounds) and then surface roughened (except in a control group of 9 specimens of three composite types). Each composite type was divided into three subgroups of surface treatments: (1) Bur abrading and phosphoric acid (PA) etching, (2) sandblasting and PA etching, and (3) hydrofluoric etching and silane application (n = 15 × 9, complying with ISO TR11405). Composite blocks were repaired with the same composite type but of a different color. Microtensile bond strength and modes of failure were analyzed statistically using two-way analyses of variance, Tukey and Chi-square tests (α = 0.05). Results: There were significant differences between three composite resins (P < 0.0001) and treatment techniques (P < 0.0001). Their interaction was nonsignificant (P = 0.228). The difference between nanofilled and nanohybrid was not significant. However, the microhybrid composite showed a significantly higher bond strength (Tukey P < 0.05). Sandblasting was significantly superior to the other two methods, which were not different from each other. Conclusion: Within the limitations of this in vitro study, it seems that microhybrid composite might have higher repair strengths than two evaluated nanocomposites. Among the assessed preparation techniques, sandblasting followed by PA etching might produce the highest bond strength. PMID:26759592

  3. Effect of different surface treatments on the shear bond strength of nanofilled composite repairs.

    Science.gov (United States)

    Ahmadizenouz, Ghazaleh; Esmaeili, Behnaz; Taghvaei, Arnica; Jamali, Zahra; Jafari, Toloo; Amiri Daneshvar, Farshid; Khafri, Soraya

    2016-01-01

    Background. Repairing aged composite resin is a challenging process. Many surface treatment options have been proposed to this end. This study evaluated the effect of different surface treatments on the shear bond strength (SBS) of nano-filled composite resin repairs. Methods. Seventy-five cylindrical specimens of a Filtek Z350XT composite resin were fabricated and stored in 37°C distilled water for 24 hours. After thermocycling, the specimens were divided into 5 groups according to the following surface treatments: no treatment (group 1); air abrasion with 50-μm aluminum oxide particles (group 2); irradiation with Er:YAG laser beams (group 3); roughening with coarse-grit diamond bur + 35% phosphoric acid (group 4); and etching with 9% hydrofluoric acid for 120 s (group 5). Another group of Filtek Z350XT composite resin samples (4×6 mm) was fabricated for the measurement of cohesive strength (group 6). A silane coupling agent and an adhesive system were applied after each surface treatment. The specimens were restored with the same composite resin and thermocycled again. A shearing force was applied to the interface in a universal testing machine. Data were analyzed using one-way ANOVA and post hoc Tukey tests (P composite resin used.

  4. Variations in the Articular Facets on Superior Surface of Calcaneus in North Indian Population: A Dry Bone Study

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    G.S. Gindha

    2014-11-01

    Full Text Available This study was conducted in the department of anatomy of Gian Sagar Medical College, Ramnagar, Rajpura, District Patiala. 325 dry calcanei were studied. Out of which 167 were of right side and 158 were of left side and are of both sexes. The facet for talus were observed in all the calcanei. The grouping was done on the basis of number of facets present on the superior surface of calcanei. Group-I was having single facet on the two bones only (0.615 %. Group-II was having two facets and this group was further divided into three subgrpoups i.e Group-II (A,B,C, Group-II A (15.69 % of right side and (12.00 % left side. Group-II C (0.31 % of right side only. Group-III was having three facets i.e (20.62%. it was further divided into two subgroups i.e Group-III (A,B. Group-III A (8.62 % of right side and (12.00 % of left side and Group-III B (4.92 % right side and (4.3 % left side . It was concluded that the variations in differences between various types of facets on calcanei can result from differences in gait, habit of shoe wearing, sitting posture, clinical changes and embryological abnormalities of foot. Some of the types of facets can produce the problems in gait and can also cause pain in foot.

  5. 自体骨髓间充质干细胞藻酸钙载体复合物对兔膝关节软骨缺损修复影响的实验研究%The experimental study of repairing effect after embedding compound including auto-bone marrow mesenchymal stem cells and calcium-algitate in rabbits articular genu defect

    Institute of Scientific and Technical Information of China (English)

    于灏; 辛畅泰

    2014-01-01

    connecting with subcartilage-bone is visible. There are many collagen fibre presented emission-like in the extracellular matrix. On the surface of defects in group B, however, there are still plenty of fibre tissue and the boundary remains distinctive. 3-5 chondrocytes possessing obvious lacunes stand in line in the filling tissue of group A, and much more than that in group B. The phenomenon above can be scarcely observed in group C. The number of vigorous chondrocytes-collagen typeⅡ (+), rough endoplasmic reticulum in cytoplasm dialating etc. In group A is more than that of group B. It is the lest in group C. Considerable fibra tissue can be seen in the defect of group D after 90 days. The integration between filling tissue and subcartilage-bone or normal circum-articular cartilage is un-ideal. Conclusion Adding bFGF and VitC has positive function in improving the repairing effect of the defect location when embedding the compound composed of auto-MSCs and calcium alginate to the defect of knee joint.%目的:软骨组织多处于人体骨骼的重要部位,其缺损修复一直为临床急待解决的难题,用组织工程方法修复关节软骨缺损是近年来正在研究的新途径。其中绝大多数研究几乎均着重体外培养条件的研究[1,2],而忽略了对于改善局部微环境的探讨,为此,本实验试图在载体复合物植入软骨缺损微环境内时,增加能促进MSCs分裂、增殖、分化及血管新生的bFGF及参与和活跃成软骨细胞合成软骨基质及纤维的维生素C等,从而达到提高软骨缺损修复疗效的目的。方法从24只3月龄新西兰大耳白兔髂骨处抽取骨髓,以密度梯度离心法分离出骨髓间充质干细胞(MSCs)作为种子细胞进行扩增培养至第三代,制成细胞悬液,而后在自制模具中与藻酸钙制备成与兔膝关节软骨全层缺损(直径4mm、深度4mm)相一致的载体复合物同时加入bFGF和维生素C,将该载体复

  6. Shear bond strength of different surface treatments in bulk fill, microhybrid, and nanoparticle repair resins

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    de Jesus Tavarez RR

    2017-07-01

    Full Text Available Rudys Rodolfo de Jesus Tavarez,1 Lauber Jose dos Santos Almeida Júnior,2 Tayanne Christine Gomes Guará,1 Izabella Santos Ribeiro,1 Etevaldo Matos Maia Filho,1 Leily Macedo Firoozmand2 1Department of Restorative Dentistry, Ceuma University (CEUMA, 2Department of Dentistry I, University Federal of Maranhão (UFMA, São Luís, Maranhão, Brazil Objectives: The purpose of this study was to evaluate the influence of surface treatment and different types of composite resin on the microshear bond strength of repairs. Materials and methods: Seventy-two specimens (n=72 were prepared using a nanoparticle resin and stored in artificial saliva at 37 ± 1°C for 24 h. After this period, the specimens (n=24 were restored with microhybrid resin P60 (3M ESPE, nanoparticle resin Filtek Z350 (3M ESPE, and Bulk Fill Surefil SDR Flow (Dentsply composite resins. Previously, the surfaces of the samples were treated, forming the following subgroups (n=12: (A conditioned with 37% phosphoric acid for 30 s, and (B abrasioned with a diamond tip for 3 s and conditioned with 37% phosphoric acid. In all groups, before insertion of the composite resin, the adhesive system Adper Single Bond 2 was actively applied and photopolymerized for 20 s. Results: The microshear test was executed to assess bond strength. Kruskal–Wallis (p<0.05 and Mann–Whitney statistical tests showed significant statistical difference considering that the bulk-fill resin turned out to have a lower bond strength than the conventional nanoparticle and microhybrid composites. With regard to the technique, the roughening with diamond bur followed by the application of phosphoric acid exhibited values higher than the exclusive use of acid. Conclusion: The microshear bond strength of the composite resin repairs varies in accordance with the type of composite resin utilized, and roughening the surface increased the bond strength of these materials. Keywords: bulk-fill resins, composite resins, dental

  7. Chondrocyte outgrowth into a gelatin scaffold in a single impact load model of damage/repair – effect of BMP-2

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    Vincent Thea

    2007-12-01

    Full Text Available Abstract Background Articular cartilage has little capacity for repair in vivo, however, a small number of studies have shown that, in vitro, a damage/repair response can be induced. Recent work by our group has shown that cartilage can respond to single impact load and culture by producing repair cells on the articular surface. The purpose of this study was to identify whether chondrocyte outgrowth into a 3D scaffold could be observed following single impact load and culture. The effect of bone morphogenic-2 (BMP-2 on this process was investigated. Methods Cartilage explants were single impact loaded, placed within a scaffold and cultured for up to 20 days +/- BMP-2. Cell numbers in the scaffold, on and extruding from the articular surface were quantified and the immunohistochemistry used to identify the cellular phenotype. Results Following single impact load and culture, chondrocytes were observed in a 3D gelatin scaffold under all culture conditions. Chondrocytes were also observed on the articular surface of the cartilage and extruding out of the parent cartilage and on to the cartilage surface. BMP-2 was demonstrated to quantitatively inhibit these events. Conclusion These studies demonstrate that articular chondrocytes can be stimulated to migrate out of parent cartilage following single impact load and culture. The addition of BMP-2 to the culture medium quantitatively reduced the repair response. It may be that the inhibitory effect of BMP-2 in this experimental model provides a clue to the apparent inability of articular cartilage to heal itself following damage in vivo.

  8. Effect of different surface treatments on the shear bond strength of nanofilled composite repairs

    Science.gov (United States)

    Ahmadizenouz, Ghazaleh; Esmaeili, Behnaz; Taghvaei, Arnica; Jamali, Zahra; Jafari, Toloo; Amiri Daneshvar, Farshid; Khafri, Soraya

    2016-01-01

    Background. Repairing aged composite resin is a challenging process. Many surface treatment options have been proposed to this end. This study evaluated the effect of different surface treatments on the shear bond strength (SBS) of nano-filled composite resin repairs. Methods. Seventy-five cylindrical specimens of a Filtek Z350XT composite resin were fabricated and stored in 37°C distilled water for 24 hours. After thermocycling, the specimens were divided into 5 groups according to the following surface treatments: no treatment (group 1); air abrasion with 50-μm aluminum oxide particles (group 2); irradiation with Er:YAG laser beams (group 3); roughening with coarse-grit diamond bur + 35% phosphoric acid (group 4); and etching with 9% hydrofluoric acid for 120 s (group 5). Another group of Filtek Z350XT composite resin samples (4×6 mm) was fabricated for the measurement of cohesive strength (group 6). A silane coupling agent and an adhesive system were applied after each surface treatment. The specimens were restored with the same composite resin and thermocycled again. A shearing force was applied to the interface in a universal testing machine. Data were analyzed using one-way ANOVA and post hoc Tukey tests (P < 0.05). Results. One-way ANOVA indicated significant differences between the groups (P < 0.05). SBS of controls was significantly lower than the other groups; differences between groups 2, 3, 4, 5 and 6 were not significant. Surface treatment with diamond bur + 35% phosphoric acid resulted in the highest bond strength. Conclusion. All the surface treatments used in this study improved the shear bond strength of nanofilled composite resin used. PMID:27092209

  9. Effect of different surface treatments on the shear bond strength of nanofilled composite repairs

    Directory of Open Access Journals (Sweden)

    Ghazaleh Ahmadizenouz

    2016-03-01

    Full Text Available Background. Repairing aged composite resin is a challenging process. Many surface treatment options have been proposed to this end. This study evaluated the effect of different surface treatments on the shear bond strength (SBS of nano-filled composite resin repairs. Methods. Seventy-five cylindrical specimens of a Filtek Z350XT composite resin were fabricated and stored in 37°C distilled water for 24 hours. After thermocycling, the specimens were divided into 5 groups according to the following surface treatments: no treatment (group 1; air abrasion with 50-μm aluminum oxide particles (group 2; irradiation with Er:YAG laser beams (group 3; roughening with coarse-grit diamond bur + 35% phosphoric acid (group 4; and etching with 9% hydrofluoric acid for 120 s (group 5. Another group of Filtek Z350XT composite resin samples (4×6 mm was fabricated for the measurement of cohesive strength (group 6. A silane coupling agent and an adhesive system were applied after each surface treatment. The specimens were restored with the same composite resin and thermocycled again. A shearing force was applied to the interface in a universal testing machine. Data were analyzed using one-way ANOVA and post hoc Tukey tests (P < 0.05. Results. One-way ANOVA indicated significant differences between the groups (P < 0.05. SBS of controls was significantly lower than the other groups; differences between groups 2, 3, 4, 5 and 6 were not significant. Surface treatment with diamond bur + 35% phosphoric acid resulted in the highest bond strength. Conclusion. All the surface treatments used in this study improved the shear bond strength of nanofilled composite resin used.

  10. ORV Arthroscopic Transosseous Bony Bankart Repair.

    Science.gov (United States)

    Myer, Daniel M; Caldwell, Paul E

    2012-12-01

    The arthroscopic treatment of the "bony Bankart lesion" continues to evolve. We present a novel technique that we developed at Orthopaedic Research of Virginia, the "transosseous bony Bankart repair," which incorporates several essential concepts to provide for optimal healing and rehabilitation. We promote arthroscopic repair emphasizing bone preservation, a fracture interface without interposing sutures, the ability to reduce capsular volume, and multiple points of stable glenolabral fixation. Our technique positions suture anchors within the subchondral bone of the intact glenoid to allow for an anatomic reduction of the bony fragment. By use of an arthroscopic drill, spinal needle, and nitinol suture passing wire, the sutures are passed in a retrograde fashion through the bony Bankart fragment and anterior capsule in a mattress configuration. Additional inferior and superior anchors are placed to further provide stability and reduce capsular volume. While maximizing fracture surface area and optimizing bony healing, the end result is an anatomic reduction of the bony fragment and the glenoid articular surface.

  11. Study on nano-structured hydroxyapatite/zirconia stabilized yttria on healing of articular cartilage defect in rabbit

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    Amir Sotoudeh

    2013-05-01

    Full Text Available PURPOSE: Articular Cartilage has limited potential for self-repair and tissue engineering approaches attempt to repair articular cartilage by scaffolds. We hypothesized that the combined hydroxyapatite and zirconia stabilized yttria would enhance the quality of cartilage healing. METHODS: In ten New Zealand white rabbits bilateral full-thickness osteochondral defect, 4 mm in diameter and 3 mm depth, was created on the articular cartilage of the patellar groove of the distal femur. In group I the scaffold was implanted into the right stifle and the same defect was created in the left stifle without any transplant (group II. Specimens were harvested at 12 weeks after implantation, examined histologically for morphologic features, and stained immunohistochemically for type-II collagen. RESULTS: In group I the defect was filled with a white translucent cartilage tissue In contrast, the defects in the group II remained almost empty. In the group I, the defects were mostly filled with hyaline-like cartilage evidenced but defects in group II were filled with fibrous tissue with surface irregularities. Positive immunohistochemical staining of type-II collagen was observed in group I and it was absent in the control group. CONCLUSION: The hydroxyapatite/yttria stabilized zirconia scaffold would be an effective scaffold for cartilage tissue engineering.

  12. [Intra-articular injections].

    Science.gov (United States)

    Chapelle, Ch

    2015-09-01

    It is not unusual for a specialist or general practitioner to be presented with a pathology which necessitates the use of an intra-articular injection of corticosteroids, hyaluronic acid or a local anaesthetic. It would seem to be interesting to update and to precise the techniques and methods of intraarticular injections which have appeared in recent international publications, when we know that 30 % of the injections given into the knee and so called "dry" are incorrect and, therefore, inefficient. The indication of an articular injection depends, firstly, on the diagnosis which should be done with great care; after which should be an objective analysis complete with secondary effects linked to both the injection and the product used. The conditions of asepsis, the choice of needles and quantities of the injection and even the ways of the injections should be reviewed in detail. The last studies clearly question the secondary effects of the cartilage degradations of the cortisone given as an intra-articular injection and shows its efficiency on the pain and inflammatory phenomonen in osteoarthritis. Studies on hyaluronic acid are often contradictory going from a modest result to an important pain relief but it is necessary to be aware that the objective criteria are difficult to interpret. The use of local anaesthetics in intra-articular is limited by the few indications in view of the major risk of aggravating the pre-existing lesions by the disappearing signs of pain.

  13. Repair of osteochondral defects with allogeneic tissue engineered cartilage implants.

    Science.gov (United States)

    Schreiber, R E; Ilten-Kirby, B M; Dunkelman, N S; Symons, K T; Rekettye, L M; Willoughby, J; Ratcliffe, A

    1999-10-01

    The objective of this study was to evaluate the effect of allogeneic tissue engineered cartilage implants on healing of osteochondral defects. Rabbit chondrocytes were cultured in monolayer, then seeded onto biodegradable, three-dimensional polyglycolic acid meshes. Cartilage constructs were cultured hydrodynamically to yield tissue with relatively more (mature) or less (immature) hyalinelike cartilage, as compared with adult rabbit articular cartilage. Osteochondral defects in the patellar grooves of both stifle joints either were left untreated or implanted with allogeneic tissue engineered cartilage. Histologic samples from in and around the defect sites were examined 3, 6, 9, and 12, and 24 months after surgery. By 9 months after surgery, defects sites treated with cartilage implants contained significantly greater amounts of hyalinelike cartilage with high levels of proteoglycan, and had a smooth, nonfibrillated articular surface as compared to untreated defects. In contrast, the repair tissue formed in untreated defects had fibrillated articular surfaces, significant amounts of fibrocartilage, and negligible proteoglycan. These differences between treated and untreated defects persisted through 24 months after surgery. The results of this study suggest that the treatment of osteochondral lesions with allogenic tissue engineered cartilage implants may lead to superior repair tissue than that found in untreated osteochondral lesions.

  14. Arthroscopic Bony Bankart Repair Using Double-Threaded Headless Screw: A Case Report

    OpenAIRE

    Takeshi Kokubu; Issei Nagura; Yutaka Mifune; Masahiro Kurosaka

    2012-01-01

    We present a case of arthroscopic fixation for bony Bankart lesion using a double-threaded cannulated screw. A 39-year-old man sustained a left shoulder injury from a motorcycle accident. Radiographs showed bony Bankart lesion and CT revealed 40% defect of glenoid articular surface. Arthroscopic fixation was performed using double-threaded cannulated screw after the bony fragment was reduced by suturing the labrum at the edge with a suture anchor. Arthroscopic bony Bankart repair using double...

  15. Elbow dislocation and articular fracture of the distal humerus%肘关节脱位与肱骨远端关节内骨折

    Institute of Scientific and Technical Information of China (English)

    Andrés Arizmendi; Santiago Lozano-Calderón; David C. Ring; Jesse B. Jupiter

    2006-01-01

    Objective To describe dislocation of the elbow with articular fracture of the distal humerus, a type of elbow fracture-dislocation about which little has been written. Methods Four patients with a dislocation of the elbow and fracture of the distal humerus were identified. Three had dislocation and complex intraarticular fracture of the capitellum, trochlea, and lateral epicondyle. Results Two patients (one treated with a second operation to address avascular necrosis of the capitellum) achieved a functional arc of elbow motion and one patient was lost after removal of the implants 3 months after fracture with documented healing. The fourth patient had a complex open fracture dislocation involving the entire articular surface. An attempt to salvage the articular surface resulted in deep infection. Extensive heterotopic bone led to arthrodesis of the elbow. Conclusions Dislocations of the elbow with articular fracture of the humerus are uncommon. Most injuries involve the capitellum, lateral trochlea, and lateral epicondyle. Open reduction and internal fixation of the distal humerus fracture can restore stability without repairing the medial collateral ligament.

  16. Biologic Treatments for Sports Injuries II Think Tank-Current Concepts, Future Research, and Barriers to Advancement, Part 3: Articular Cartilage.

    Science.gov (United States)

    Zlotnicki, Jason P; Geeslin, Andrew G; Murray, Iain R; Petrigliano, Frank A; LaPrade, Robert F; Mann, Barton J; Musahl, Volker

    2016-04-01

    Focal chondral defects of the articular surface are a common occurrence in the field of orthopaedics. These isolated cartilage injuries, if not repaired surgically with restoration of articular congruency, may have a high rate of progression to posttraumatic osteoarthritis, resulting in significant morbidity and loss of function in the young, active patient. Both isolated and global joint disease are a difficult entity to treat in the clinical setting given the high amount of stress on weightbearing joints and the limited healing potential of native articular cartilage. Recently, clinical interest has focused on the use of biologically active compounds and surgical techniques to regenerate native cartilage to the articular surface, with the goal of restoring normal joint health and overall function. This article presents a review of the current biologic therapies, as discussed at the 2015 American Orthopaedic Society for Sports Medicine (AOSSM) Biologics Think Tank, that are used in the treatment of focal cartilage deficiencies. For each of these emerging therapies, the theories for application, the present clinical evidence, and specific areas for future research are explored, with focus on the barriers currently faced by clinicians in advancing the success of these therapies in the clinical setting.

  17. Repair of rabbit articular cartilage and subchondral defects using porous silk fibroin/hydroxyapatite combined with adipose-derived stromal cells%多孔丝素蛋白/羟基磷灰石复合脂肪间充质干细胞修复兔关节软骨及软骨下骨缺损

    Institute of Scientific and Technical Information of China (English)

    鞠刚; 徐卫袁; 张亚; 张兴祥; 严飞; 沙卫平

    2011-01-01

    BACKGROUND: Silk fibroin/hydroxyapatite (SF/HA) is a good scaffold for three-dimensional culture of cells, and is a common material to repair bone defect with good biocompatibility. Adipose -derived stem cells (ADSCs) which can differentiate into bone and cartilage cells are ideal for repairing cartilage defect.OBJECTIVE: To observe the effects of the repair of articular cartilage and subchondral defects in rabbit knee joints with transforming growth factor-?1 and insulin like growth factor-1 in combination with SF/HA and ADSCs.METHODS: A total of 56 New Zealand rabbits were selected, and 2 were used for cultures of ADSCs, which were seeded onto SF/HA at a concentration of 3×109/L. The remaining 54 rabbits were used to establish model of articular cartilage and subchondral defects and randomly assigned to composite, simple and blank control groups. The composite and simple groups were respectively implanted with SF/HA/ADSCs scaffold and SF/HA scaffold. The blank control group was not implanted any materials. Repair of defects was observed and compared by gross, imaging and histological observations.RESULTS AND CONCLUSION: At 12 weeks, gross observation, CT, MRI and histological observations demonstrated that the articular cartilage and subchondral defects were repaired entirely in composite group. The color of repaired tissues was similar to surrounding cartilage. There was no evidence of the residue of silk fibroin or the infiltration of leukocytes. Defects were repaired partially and repaired with cartilage fibrosa in simple group. However, defects remained unchanged in blank control group.Results showed that SF/HA with ADSCs composite could successfully repair articular cartilage and subchondral defects of a rabbit knee joints and the effect was superior to SF/HA scaffold alone. The method for repairing the full-thickness hyaline cartilage defects and reconstructing anatomical structure and function of joints using SF/HA with ADSCs is feasible and promising to

  18. Canine sacroiliac luxation: anatomic study of the craniocaudal articular surface angulation of the sacrum to define a safe corridor in the dorsal plane for placement of screws used for fixation in lag fashion.

    Science.gov (United States)

    Bowlt, Kelly L; Shales, Christopher J

    2011-01-01

    To define a safe corridor in the dorsal plane relative to the articular surface for placement of a single screw in lag fashion to achieve stabilization of sacroiliac luxation in the dog. Cadaveric study. Dorsoventral radiographs of denuded canine sacra (n=49) were taken to determine the safe corridor in the craniocaudal plane, and the maximum, optimum and minimum angles were calculated that would allow a screw inserted in lag fashion to engage at least 60% of the width of the sacral body without cranial or caudal penetration through the bone. The mean safe corridor in the dorsal plane is ∼24° wide. Mean craniocaudal minimum, optimum and maximum drill angles from the drill start point were 88°, 100°, and 111° from the articular surface, respectively. No single angle will completely avoid risk of screw penetration beyond the safe corridor cranially and caudally. There is sufficient anatomic variation between different canine sacra that a single angle cannot be recommended for screw placement in the dorsal plane. A standard angle cannot be recommended for screw placement in lag fashion within the canine sacrum in the dorsal plane. Because of the narrow width of the safe corridor, preoperative measurements on radiographs are recommended and a range of angled drill guides may be useful to decrease surgeon margin of error. © Copyright 2010 by The American College of Veterinary Surgeons.

  19. Effect of Mechanical Surface Treatment on the Repair Bond Strength of the Silorane-based Composite Resin

    Directory of Open Access Journals (Sweden)

    Parnian Alizadeh Oskoee

    2014-06-01

    Full Text Available Background and aims. A proper bond must be created between the existing composite resin and the new one for successful repair. The aim of this study was to compare the effect of three mechanical surface treatments, using diamond bur, air abrasion, and Er,Cr:YSGG laser, on the repair bond strength of the silorane-based composite resin. Materials and methods. Sixty cylindrical composite resin specimens (Filtek Silorane were fabricated and randomly divided into four groups according to surface treatment: group 1 (control group without any mechanical surface treatment, groups 24 were treated with air abrasion, Er,Cr:YSGG laser, and diamond bur, respectively. In addition, a positive control group was assigned in order to measure the cohesive strength. Silorane bonding agent was used in groups 14 before adding the new composite resin. Then, the specimens were subjected to a shear bond strength test and data was analyzed using one-way ANOVA and post hoc Tukey tests at a significance level of P < 0.05. The topographical effects of surface treatments were characterized under a scanning electron microscope. Results. There were statistically significant differences in the repair bond strength values between groups 1 and 2 and groups 3 and 4 (P < 0.001. There were no significant differences between groups 1 and 2 (P = 0.98 and groups 3 and 4 (P = 0.97. Conclusion. Surface treatment using Er,Cr:YSGG laser and diamond bur were effective in silorane-based composite resin repair.

  20. The effect of joint surface contours and glass fiber reinforcement on the transverse strength of repaired acrylic resin: An in vitro study

    Directory of Open Access Journals (Sweden)

    Nayana Anasane

    2013-01-01

    Full Text Available Background : Denture fracture is an unresolved problem in complete denture prosthodontics. However, the repaired denture often experiences a refracture at the repaired site due to poor transverse strength. Hence, this study was conducted to evaluate the effect of joint surface contours and glass fiber reinforcement on the transverse strength of repaired acrylic resins. Materials and Methods: A total of 135 specimens of heat polymerized polymethyl methacrylate resin of dimensions 64 × 10 × 2.5 mm were fabricated. Fifteen intact specimens served as the control and 120 test specimens were divided into four groups (30 specimens each, depending upon the joint surface contour (butt, bevel, rabbet and round, with two subgroups based on type of the repair. Half of the specimens were repaired with plain repair resin and the other half with glass fibers reinforced repair resin. Transverse strength of the specimens was determined using three-point bending test. The results were analyzed using one-way ANOVA and Tukey post-hoc test (α= 0.05. Results: Transverse strength values for all repaired groups were significantly lower than those for the control group ( P < 0.001 (88.77 MPa, with exception of round surface design repaired with glass fiber reinforced repair resin (89.92 MPa which was significantly superior to the other joint surface contours ( P < 0.001. Glass fiber reinforced resin significantly improved the repaired denture base resins as compared to the plain repair resin ( P < 0.001. Conclusion: Specimens repaired with glass fiber reinforced resin and round surface design exhibited highest transverse strength; hence, it can be advocated for repair of denture base resins.

  1. En bloc joystick reduction of a comminuted intra-articular distal radius fracture: a technical trick.

    Science.gov (United States)

    Siegall, Evan; Ziran, Bruce

    2014-08-01

    A patient with a 1-month-old intra-articular distal radius fracture (treated closed in a splint) presented with an unacceptable degree of pain and stiffness caused by shortening and dorsal angulation of the distal radius. The fracture was comminuted with 4 or 5 distinct fragments, several involving the articular surface. Surgical correction was attempted. During the procedure, it was noted that, though the distal radius was shortened and angulated, there was actually acceptable congruity of the articular surface itself, despite the intra-articular nature of the fracture. Bone quality was poor and healing incomplete. Thus, we were concerned the currently congruous articular surface would fall apart with manipulation. Given this situation, we used a unique scaffolding technique with Kirschner wires placed in perpendicular fashion to both hold the articular surface intact and manipulate it en bloc. This technique is a simple way to turn a complex fracture into an easily reduced 2-part fracture.

  2. 腺病毒携带骨形态发生蛋白14基因转染脂肪干细胞修复损伤关节软骨%Adipose-derived stem cells transfected with adenovirus carrying bone morphogenetic protein 14 for repair of articular cartilage injury

    Institute of Scientific and Technical Information of China (English)

    马洪斌; 李运祥; 王铭伦

    2015-01-01

    BACKGROUND:The articular cartilage has weak self-repair ability, mainly due to its lack of trophoblast cels in blood vessels and slow cel metabolism. Current treatment methods cannot restore the original function of the cartilage tissue, and cartilage tissue engineering in recent years has garnered increasing attention. OBJECTIVE:To observe the effect of adipose-derived stem cels transfected with bone morphogenetic protein 14 combined with type I colagen sponge scaffold on the repair of articular cartilage injury in the knee of rabbits. METHODS: Adipose-derived stem cels were isolated and cultured from rabbit subcutaneous adipose tissue, and transfected with Ad-CMV-BMP-14-IRES-hrGFP-1. Type I colagen sponge scaffold with the transfected adipose-derived stem cels was used to repair articular cartilage injury in the knee of rabbits. Twelve weeks after operation, the articular tissue was taken for gross assessment and histological evaluation. RESULTS AND CONCLUSION: The expressions of bone morphogenetic protein 14, type II colagen and Sox-9 were higher in cels transfected with bone morphogenetic protein 14 than untransfected ones. At 12 weeks after operation, adipose-derived stem cels transfected with bone morphogenetic protein 14 combined with type I colagen sponge scaffold had good repair effect on articular cartilage injuries, and the injured cartilage tissues were smooth and had good texture, color and integration junction; adipose-derived stem cels combined with type I colagen sponge scaffold could partialy repair the injured cartilage tissues that had similar color and texture to normal tissues, and there was a remarkable boundary between the repaired tissue and normal cartilage tissue;simple type I colagen sponge scaffold was almost colapsed, and no hyaline cartilage tissue formed. These findings indicate that transfection of bone morphogenetic protein 14 can strengthen the ability of adipose-derived stem cels dramaticaly to repair cartilage injuries.%背景

  3. Effects of surface conditioning on repair bond strengths of non-aged and aged microhybrid, nanohybrid, and nanofilled composite resins

    NARCIS (Netherlands)

    Rinastiti, Margareta; Siswomihardjo, Widowati; Busscher, Henk J.; Ozcan, Mutlu

    2011-01-01

    This study evaluates effects of aging on repair bond strengths of microhybrid, nanohybrid, and nanofilled composite resins and characterizes the interacting surfaces after aging. Disk-shaped composite specimens were assigned to one of three aging conditions: (1) thermocycling (5,000x, 5-55 degrees

  4. Effects of surface conditioning on repair bond strengths of non-aged and aged microhybrid, nanohybrid, and nanofilled composite resins

    NARCIS (Netherlands)

    Rinastiti, Margareta; Siswomihardjo, Widowati; Busscher, Henk J.; Ozcan, Mutlu

    2011-01-01

    This study evaluates effects of aging on repair bond strengths of microhybrid, nanohybrid, and nanofilled composite resins and characterizes the interacting surfaces after aging. Disk-shaped composite specimens were assigned to one of three aging conditions: (1) thermocycling (5,000x, 5-55 degrees C

  5. New Surface-Treatment Technique of Concrete Structures Using Crack Repair Stick with Healing Ingredients.

    Science.gov (United States)

    Ahn, Tae-Ho; Kim, Hong-Gi; Ryou, Jae-Suk

    2016-08-04

    This study focused on the development of a crack repair stick as a new repair method along with self-healing materials that can be used to easily repair the cracks in a concrete structure at the construction site. In developing this new repair technique, the self-healing efficiency of various cementitious materials was considered. Likewise, a crack repair stick was developed to apply to concrete structures with 0.3 mm or lower crack widths. The crack repair stick was made with different materials, such as cement, an expansive material (C12A₇), a swelling material, and calcium carbonate, to endow it with a self-healing property. To verify the performance of the crack repair stick for concrete structures, two types of procedures (field experiment and field absorption test) were carried out. As a result of such procedures, it was concluded that the developed crack repair stick could be used on concrete structures to reduce repair expenses and for the improved workability, usability, and serviceability of such structures. On the other hand, to evaluate the self-healing performance of the crack repair stick, various tests were conducted, such as the relative dynamic modulus of elasticity test, the water tightness test, the water permeability test, observation via a microscope, and scanning electron microscope (SEM) analysis. From the results, it is found that water leakage can be prevented and that the durability of a concrete structure can be improved through self-healing. Also, it was verified that the cracks were perfectly closed after 28 days due to application of the crack repair stick. These results indicate the usability of the crack repair stick for concrete structures, and its self-healing efficiency.

  6. New Surface-Treatment Technique of Concrete Structures Using Crack Repair Stick with Healing Ingredients

    Directory of Open Access Journals (Sweden)

    Tae-Ho Ahn

    2016-08-01

    Full Text Available This study focused on the development of a crack repair stick as a new repair method along with self-healing materials that can be used to easily repair the cracks in a concrete structure at the construction site. In developing this new repair technique, the self-healing efficiency of various cementitious materials was considered. Likewise, a crack repair stick was developed to apply to concrete structures with 0.3 mm or lower crack widths. The crack repair stick was made with different materials, such as cement, an expansive material (C12A7, a swelling material, and calcium carbonate, to endow it with a self-healing property. To verify the performance of the crack repair stick for concrete structures, two types of procedures (field experiment and field absorption test were carried out. As a result of such procedures, it was concluded that the developed crack repair stick could be used on concrete structures to reduce repair expenses and for the improved workability, usability, and serviceability of such structures. On the other hand, to evaluate the self-healing performance of the crack repair stick, various tests were conducted, such as the relative dynamic modulus of elasticity test, the water tightness test, the water permeability test, observation via a microscope, and scanning electron microscope (SEM analysis. From the results, it is found that water leakage can be prevented and that the durability of a concrete structure can be improved through self-healing. Also, it was verified that the cracks were perfectly closed after 28 days due to application of the crack repair stick. These results indicate the usability of the crack repair stick for concrete structures, and its self-healing efficiency.

  7. Intra-articular capacity of the elbow joint.

    Science.gov (United States)

    Van Den Broek, Mathias; Van Riet, Roger

    2017-09-01

    The intra-articular capacity of the elbow joint is reported to be 23 ± 4 ml on cadaveric elbows. During years, this value was the standard. The aim of this observational study was to reanalyze the volume of the elbow joint on live patients. Measurement of the intra-articular capacity and pressure of the elbow joint was performed on 30 patients (mean age: 43.8 years) undergoing elbow arthroscopy. Intra-articular capacity was recorded when the elbow moved to the maximum lose packed position and/or when there was a sudden drop in pressure, indicating a capsular rupture (maximum capacity). Indications for arthroscopy were loose bodies, osteoarthritis, synovitis, radial head resection, and lateral collateral ligament repair. Mean intra-articular capacity and pressure were 35.8 ml and 557.5 mm Hg, respectively. Mean maximal capacity was 40.5 ml. We conclude that the intra-articular capacity of the elbow joint is substantially greater than reported in previous studies. Clin. Anat. 30:795-798, 2017. © 2017Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. Enhanced cartilage repair in 'healer' mice-New leads in the search for better clinical options for cartilage repair.

    Science.gov (United States)

    Fitzgerald, Jamie

    2017-02-01

    Adult articular cartilage has a poor capacity to undergo intrinsic repair. Current strategies for the repair of large cartilage defects are generally unsatisfactory because the restored cartilage does not have the same resistance to biomechanical loading as authentic articular cartilage and degrades over time. Recently, an exciting new research direction, focused on intrinsic cartilage regeneration rather than fibrous repair by external means, has emerged. This review explores the new findings in this rapidly moving field as they relate to the clinical goal of restoration of structurally robust, stable and non-fibrous articular cartilage following injury.

  9. Effects of surface conditioning on repair bond strengths of non-aged and aged microhybrid, nanohybrid, and nanofilled composite resins.

    Science.gov (United States)

    Rinastiti, Margareta; Özcan, Mutlu; Siswomihardjo, Widowati; Busscher, Henk J

    2011-10-01

    This study evaluates effects of aging on repair bond strengths of microhybrid, nanohybrid, and nanofilled composite resins and characterizes the interacting surfaces after aging. Disk-shaped composite specimens were assigned to one of three aging conditions: (1) thermocycling (5,000 ×, 5-55 °C), (2) storage in water at 37 °C for 6 months, or (3) immersion in citric acid at 37 °C, pH 3 for 1 week; a non-aged group acted as the control. Two surface conditionings were selected: intermediate adhesive resin application (IAR-application) and chairside silica coating followed by silanization and its specific IAR-application (SC-application). Composite resins, of the same kind as their substrate, were adhered onto the substrates, and repair shear bond strengths were determined, followed by failure type evaluation. Filler particle exposure was determined by X-ray photoelectron spectroscopy and surface roughness analyzed using scanning electron and atomic force microscopy. Surface roughness increased in all composite resins after aging, but filler particle exposure at the surface only increased after thermocycling and citric acid immersion. Composite resin type, surface conditioning, and aging method significantly influenced the repair bond strengths (p water storage. Repair bond strengths in aged composite resins after IAR-application were always lower in non-aged ones, while SC-application led to higher bond strengths than IAR-application after thermocycling and water storage. In addition, SC-application led to more cohesive failures than after IAR-application, regardless the aging method.

  10. [Structure of the articular cartilage in the middle aged].

    Science.gov (United States)

    Kop'eva, T N; Mul'diiarov, P Ia; Bel'skaia, O B; Pastel', V B

    1983-10-01

    In persons 17-83 years of age having no articular disorders 39 samples of the patellar articular cartilage, the articulated surface and the femoral head have been studied histochemically, histometrically and electron microscopically. Age involution of the articular cartilage is revealed after 40 years of age as a progressive decrease in chondrocytes density in the superficial and (to a less degree) in the intermediate zones. This is accompanied with a decreasing number of 3- and 4-cellular lacunae and with an increasing number of unicellular and hollow lacunae. In some chondrocytes certain distrophic and necrotic changes are revealed. In the articular matrix the zone with the minimal content of glycosaminoglycans becomes thicker and keratansulfate content in the territorial matrix of the cartilage deep zone grows large.

  11. Effect of four different surface treatments on shear bond strength of three porcelain repair systems: An in vitro study

    Directory of Open Access Journals (Sweden)

    Ritesh Gourav

    2013-01-01

    Full Text Available Background: Ceramic fracture in metal ceramic restorations are serious and pose an aesthetic and functional dilemma both for the patients and the dentist. This has created a demand for the development of practical repair options which do not necessitate the removal and remake of entire restorations. Aim: To evaluate and compare the effect of four different surface treatments on shear bond strength of metal ceramic specimens with three commercially available porcelain repair systems. Materials and Methods: Specimens were fabricated with a base-metal ceramic alloy and divided into three groups, to evaluate three porcelain repair systems. Each group was divided into four subgroups based on surface treatment (A sandblasting, (B sandblasting followed by etching with 9% HF (Hydrofluoric acid on surrounding ceramic, (C Use of a diamond bur on exposed metal followed by etching with 37% H 3 PO 4 and (D Control groups (D 1 , D 2 , D 3 for three groups of porcelain repair system which was not subjected to further treatment after finishing with 240 grit silicon carbide paper grinding. Shear bond strength of each group of specimens based on surface treatment were evaluated with a universal testing machine after storing in distilled water for 7 days. One way ANOVA and Tukey-HSD procedure were used to compare the mean values between and among the groups. Results: The mean shear bond strength of group III (10.402 ± 1.055 were significantly higher than group I (8.647 ± 0.990 and group II (8.099 ± 0.600 for all surface treatments. However the mean values of shear bond strength of sub-group A were significantly higher than sub-group C and D but were not significantly higher than sub-group B. Conclusion: The results of this study suggest that in fractured metal ceramic restorations the exposed metal surface treated with sandblasting or sandblasting and etching the surrounding ceramic surface with HF can increase the shear bond strength of the repaired metal

  12. The use of compliant layer prosthetic components in orthopedic joint repair and replacement: a review.

    Science.gov (United States)

    St John, Kenneth R

    2014-08-01

    The surgical repair or treatment of degenerative joint disease has traditionally involved the substitution of synthetic materials for one or both surfaces of the joint. Engineering thermoplastics, metals, and ceramics have either been widely accepted or experimentally evaluated for use as bearing surfaces in these prostheses. When engineering thermoplastics are used, the opposing surface is a metal or a ceramic, but metal-on-metal, metal-on-ceramic, and ceramic-on-ceramic have also been used or tested. Researchers have sought the opportunity to utilize materials with compressive mechanical properties more closely matching those of the natural articular cartilage. This review discusses the theory, testing, and application of elastomers for one bearing component of articular joint prostheses.

  13. Repair of articular cartilage defects in rabbits through tissue-engineered cartilage constructed with chitosan hydrogel and chondrocytes%新型壳聚糖水凝胶结合软骨细胞修复兔关节软骨缺损的实验研究

    Institute of Scientific and Technical Information of China (English)

    Ming ZHAO; Zhu CHEN; Kang LIU; Yu-qing WAN; Xu-dong LI; Xu-wei LUO; Yi-guang BAI; Ze-long YANG; Gang FENG

    2015-01-01

    Objective: In our previous work, we prepared a type of chitosan hydrogel with excelent biocompatibility. In this study, tissue-engineered cartilage constructed with this chitosan hydrogel and costal chondrocytes was used to repair the articular cartilage defects. Methods: Chitosan hydrogels were prepared with a crosslinker formed by com-bining 1,6-disocyanatohexane and polyethylene glycol. Chitosan hydrogel scaffold was seeded with rabbit chondro-cytes that had been cultured for one weekin vitro to form the preliminary tissue-engineered cartilage. This preliminary tissue-engineered cartilage was then transplanted into the defective rabbit articular cartilage. There were three treatment groups: the experimental group received preliminary tissue-engineered cartilage; the blank group received pure chitosan hydrogels; and, the control group had received no implantation. The knee joints were harvested at predetermined time. The repaired cartilage was analyzed through gross morphology, histologicaly and immuno-histochemicaly. The repairs were scored according to the international cartilage repair society (ICRS) standard. Results: The gross morphology results suggested that the defects were repaired completely in the experimental group after twelve weeks. The regenerated tissue connected closely with subchondral bone and the boundary with normal tissue was fuzzy. The cartilage lacuna in the regenerated tissue was similar to normal cartilage lacuna. The results of ICRS gross and histological grading showed that there were significant differences among the three groups (P  创新点:利用自主研发的具有良好生物相容性和稳定性的壳聚糖水凝胶与软骨细胞,在体外初步构建组织工程软骨,并尝试利用其修复缺损的关节软骨,从而为关节软骨缺损的修复提供了一种新的治疗方法。  方法:取兔肋软骨体外培养扩增,获得P2代软骨细胞,将其种植到冻干的壳聚糖水凝胶上,体

  14. Surface treatments for repair of feldspathic, leucite - and lithium disilicate-reinforced glass ceramics using composite resin.

    Science.gov (United States)

    Neis, Christian Alencar; Albuquerque, Nadine Luísa Guimarães; Albuquerque, Ivo de Souza; Gomes, Erica Alves; Souza-Filho, Celso Bernardo de; Feitosa, Victor Pinheiro; Spazzin, Aloisio Oro; Bacchi, Atais

    2015-01-01

    The aim of this study was to evaluate the efficacy of different surface conditioning methods on the microtensile bond strength of a restorative composite repair in three types of dental ceramics: lithium disilicate-reinforced, leucite-reinforced and feldspathic. Twelve blocks were sintered for each type of ceramic (n=3) and stored for 3 months in distilled water at 37 °C. The bonding surface of ceramics was abraded with 600-grit SiC paper. Surface treatments for each ceramic were: GC (control) - none; GDB - diamond bur #30 µm; GHF - hydrofluoric acid (10%); GT- tribochemical silica coating (45-μm size particles). Treatments were followed by cleaning with phosphoric acid 37% for 20 s + silane + adhesive. The composite resin was used as restorative material. After repair, samples were subjected to thermocycled ageing (10,000 cycles between 5 °C and 55 °C for 30 s). Thereafter, the samples were sectioned into 1.0 mm2 sticks and tested for microtensile bond strength with 0.5 mm/min crosshead speed. Data were compared by two-way ANOVA and Tukey's test (α=0.05). The superficial wear with diamond bur proved to be suitable for feldspathic porcelain and for leucite-reinforced glass ceramic while hydrofluoric acid-etching is indicated for repairs in lithium disilicate-reinforced ceramic; tribochemical silica coating is applicable to leucite-reinforced ceramic. Predominance of adhesive failures was observed (>85% in all groups). In conclusion, the success of surface treatments depends on the type of ceramic to be repaired.

  15. Effect of surface treatments on the tensile bond strength of repaired water-aged anterior restorative micro-fine hybrid resin composite.

    Science.gov (United States)

    Fawzy, Amr S; El-Askary, Farid S; Amer, Mohamed A

    2008-12-01

    The purpose of this study was to characterize changes in surface topography associated with different surface treatments and their effect on tensile bond strength (TBS) of repaired water-aged anterior restorative micro-fine hybrid resin composite. The TBS of repaired resin-based composite slabs either non-treated or exposed to different mechanical and/or chemical surface treatment procedures were measured. The cohesive tensile strength of non-repaired intact slabs was used as a control group. The topographical effects of acid etching, grinding, and grinding followed by acid etching were characterized by AFM and SEM. All repaired groups showed significantly lower TBS than the control group. The TBS of repaired groups was ranged from 15% to 59% of the cohesive tensile strength of the control group (18.8+/-4.5MPa). The surface roughness of the non-treated aged specimens was significantly higher than other treated specimens. Specimens treated by acid etching showed significant increase in surface area compared to the non-treated and treated specimens. Aging process resulted in the formation of degradable surface layer which adversely affects the repair bond strength. The use of silane primer prior to the application of the adhesive after mechanical grinding, with or without the use of 37% phosphoric acid etching; improves the repair bond strength.

  16. Matrix metalloproteinase-3 inhibitor I accelerates the early-stage repair of full-thickness articular cartilage defects in the knee of rats%膝关节软骨早期缺损修复中的基质金属蛋白酶3抑制剂Ⅰ

    Institute of Scientific and Technical Information of China (English)

    董福; 宋锦旗; 姜楠; 陆春

    2016-01-01

    BACKGROUND:The biomechanical properties of naturaly regenerated damaged articular cartilage that belongs to the fibrovascular tissue are far worse than those of the normal cartilage so that they cannot meet the requirements for joint function, leading to traumatic arthritis and loss of joint function. OBJECTIVE:To evaluate the effects of matrix metaloproteinase-3 (MMP-3) inhibitor I with different concentrations on the early-stage repair of ful-thickness articular cartilage defects in the knee of rats. METHODS: Twenty-four Sprague Dawley rats were randomized into control, defect (DEF), and defect combined with low-(D+L) and high-dose inhibitor (D+H) groups (n=6 for each group), respectively. Full-thickness articular cartilage defects followed by intraarticular injection of low- and high-dose MMP-3 inhibitor I for 4 weeks was administered in the later two groups. Serum MMP-3 was detected using ELISA method before and after experiment, respectively. Femoral trochleas were collected to observe characteristics of repaired tissue by gross appearance scoring and O’Driscoll histological scoring with Safranine O-Fast Green staining, and to measure type II colagen by immunohistochemistry after experiment. RESULTS AND CONCLUSION:Rats in the D+H group had obvious repair similarly to hyaline articular cartilage, while creamy white cartilage tissue and fibrous tissue repair were observed in D+L group and in DEF group. D+H group obtained the best repair results according to gross appearance scoring and O’Driscol histological scoring and the highest content of type II colagen (P  目的:评价不同水平基质金属蛋白酶3抑制剂Ⅰ对大鼠膝关节软骨早期缺损促进修复的作用。  方法:24只SD大鼠随机选取6只作为空白对照组,另18只大鼠制备膝关节软骨缺损模型后随机分为缺损组、缺损+低浓度抑制剂组及缺损+高浓度抑制剂组,后2组大鼠每周分别进行膝关节腔内注射不

  17. Effects of different surface treatments and accelerated artificial aging on the bond strength of composite resin repairs

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Veiga de Melo

    2011-12-01

    Full Text Available The purpose of the present study was to assess the bond strength of composite resin repairs subjected to different surface treatments and accelerated artificial aging. 192 cylindrical samples (CSs were prepared and divided into 24 groups (n = 8. Half of the CSs were stored in water for 24 h, and the other half were subjected to C-UV accelerated aging for non-metallic specimens. The treatments were phosphoric acid + silane + adhesive (PSA; phosphoric acid + adhesive (PA; diamond bur + phosphoric acid + silane + adhesive (DPSA; diamond bur + phosphoric acid + adhesive (DPA; air abrasion + phosphoric acid + silane + adhesive (APSA; and air abrasion + phosphoric acid + adhesive (APA. The repair was performed and the specimens were again aged as described above. A control group (n = 8 was established and did not receive any type of aging or surface treatment. The specimens were loaded to failure in shear mode with a crosshead speed of 0.5 mm/min until fracture. Data were analyzed by one-way ANOVA/Tukey's test (p < 0.05. No statistically significant differences were found among DPSA, DPA, APSA, APA, and the control group. The aged PSA and PA achieved low bonding values and were statistically different from the control group, whereas the non-aged PSA and PA presented no statistically significant difference from the control group. Repairs with the proposed surface treatments were viable on both recent and aged restorations; however, phosphoric acid + adhesive alone were effective only on recent restorations.

  18. 组织工程化软骨细胞和骨髓间充质干细胞用于修复同种异体关节软骨缺损%Tissue engineered chondrocytes and bone marrow mesenchymal stem cells for the repair of articular cartilage defects

    Institute of Scientific and Technical Information of China (English)

    孙皓; 左健

    2012-01-01

    BACKGROUND: As the articular cartilage almost has no self-repair capacity, and in clinic, the repair on it mainly depends on the autologous or allogenic cartilage transplantation, perichondrium or periosteal transplantation and the chondrocytes transplantation. The limitation of autologous cartilage source and the chronic immune rejection of allograft cartilage may eventually lead to the poor prognosis. The cartilage repaired by perichondrium or periosteum transplantation is easy to degenerate which may lead to a poor repair result.OBJECTIVE: To review the research progress of tissue engineered chondrocytes , bone marrow mesenchymal stem cells and the co-culture of them on the repair of allogeneic cartilage defects.METHODS: A computer-based search on the PubMed database and CNKI database from January 1994 to January 2012 was performed for the articles on tissue engineered chondrocytes and bone marrow mesenchymal stem cells for the repair of allograft articular cartilage defects. The English key words were "cartilage defect, allograft, chondrocyte, mesenchymal stem cells, bone marrow mesenchymal stem cells" and the Chinese keywords were "cartilage defect, allograft, chondrocyte, bone marrow mesenchymal stem cells". The repetitive articles and the articles not in English or Chinese were eliminated, and finally, a total of 35 articles were included to review.RESULTS AND CONCLUSION: With the continuous improvement of in vitro cell culture methods, chondrocytes can be isolated from the tough cartilage, and a large number of high-purity chondrocytes and new chondrocytes can be obtained. Due to the low proliferative capacity of the chondrocytes, subculture may easily lead to aging and dedifferentiation; however, the content of bone marrow mesenchymal stem cells is low in adult bone marrow, with the increasing of the passages number, the chondrogenic potential is significantly decreased. When the bone marrow mesenchymal stem cells co-cultured with chondrocytes, they can

  19. Evaluation of an extracellular matrix-derived acellular biphasic scaffold/cell construct in the repair of a large articular high-load-bearing osteochondral defect in a canine model

    Institute of Scientific and Technical Information of China (English)

    YANG Qiang; MA Xin-long; HU Yong-cheng; XU Bao-shan; PENG Jiang; LU Shi-bi; GUO Quan-yi; ZHAO Bin; ZHANG Li; WANG Ai-yuan; XU Weng-jing; XIA Qun

    2011-01-01

    Background Osteochondral lesion repair is a challenging area of orthopedic surgery.Here we aimed to develop an extraceliular matrix-derived,integrated,biphasic scaffold and to investigate the regeneration potential of the scaffold loaded with chondrogenically-induced bone marrow-derived mesenchymal stem cells (BMSCs) in the repair of a large,high-load-bearing,osteochondral defect in a canine model.Methods The biphasic scaffolds were fabricated by combining a decellularization procedure with a freeze-drying technique and characterized by scanning electron microscopy (SEM) and micro-computed tomography (micro-CT).Osteochondral constructs were fabricated in vitro using chondrogenically-induced BMSCs and a biphasic scaffold,then assessed by SEM for cell attachment.Osteochondral defects (4.2 mm (diameter) x 6 mm (depth)) were created in canine femoral condyles and treated with a construct of the biphasic scaffold/chondrogenically-induced BMSCs or with a cell-free scaffold (control group).The repaired defects were evaluated for gross morphology and by histological,biochemical,biomechanical and micro-CT analyses at 3 and 6 months post-implantation.Results The osteochondral defects of the experimental group showed better repair than those of the control group.Statistical analysis demonstrated that the macroscopic and histologic grading scores of the experimental group were always higher than those of the control group,and that the scores for the experimental group at 6 months were significantly higher than those at 3 months.The cartilage stiffness in the experimental group (6 months) was (6.95±0.79)N/mm,70.77% of normal cartilage; osteochondral bone stiffness in the experimental group was (158.16±94.30) N/mm,74.95% of normal tissue; glycosaminoglycan content of tissue-engineered neocartilage was (218±21.6) μg/mg (dry weight),84.82% of native cartilage.Micro-CT analysis of the subchondral bone showed mature trabecular bone regularly formed at 3 and 6 months

  20. Resin composite repair: Quantitative microleakage evaluation of resin-resin and resin-tooth interfaces with different surface treatments.

    Science.gov (United States)

    Celik, Cigdem; Cehreli, Sevi Burcak; Arhun, Neslihan

    2015-01-01

    The aim was to evaluate the effect of different adhesive systems and surface treatments on the integrity of resin-resin and resin-tooth interfaces after partial removal of preexisting resin composites using quantitative image analysis for microleakage testing protocol. A total of 80 human molar teeth were restored with either of the resin composites (Filtek Z250/GrandioSO) occlusally. The teeth were thermocycled (1000×). Mesial and distal 1/3 parts of the restorations were removed out leaving only middle part. One side of the cavity was finished with course diamond bur and the other was air-abraded with 50 μm Al2O3. They were randomly divided into four groups (n = 10) to receive: Group 1: Adper Single Bond 2; Group 2: All Bond 3; Group 3: ClearfilSE; Group 4: BeautiBond, before being repaired with the same resin composite (Filtek Z250). The specimens were re-thermocycled (1000×), sealed with nail varnish, stained with 0.5% basic fuchsin, sectioned mesiodistally and photographed digitally. The extent of dye penetration was measured by image analysis software (ImageJ) for both bur-finished and air-abraded surfaces at resin-tooth and resin-resin interfaces. The data were analyzed statistically. BeautiBond exhibited the most microleakage at every site. Irrespective of adhesive and initial composite type, air-abrasion showed less microleakage except for BeautiBond. The type of initial repaired restorative material did not affect the microleakage. BeautiBond adhesive may not be preferred in resin composite repair in terms of microleakage prevention. Surface treatment with air-abrasion produced the lowest microleakage scores, independent of the adhesive systems and the pre-existing resin composite type. Pre-existing composite type does not affect the microleakage issue. All-in-one adhesive resin (BeautiBond) may not be preferred in resin composite repair in terms of microleakage prevention.

  1. Effect of different surface treatments on the composite-composite repair bond strength.

    Science.gov (United States)

    Rathke, Andreas; Tymina, Yana; Haller, Bernd

    2009-09-01

    The aim of this study was to investigate the effect of different mechanical and adhesive treatments on the bond strength between pre-existing composite and repair composite using two aging times of the composite to be repaired. Standardized cylinders were made of a microhybrid composite (Spectrum TPH) and stored in saline at 37 degrees C for 24 h (n = 140) or 6 months (n = 140). Three types of mechanical roughening were selected: diamond-coated bur followed by phosphoric acid etching, mini sandblaster with 50-microm aluminum oxide powder, and 30-microm silica-coated aluminum oxide powder (CoJet Sand), respectively. Adhesive treatment was performed with the components of a multi-step bonding system (OptiBond FL) or with a one-bottle primer-adhesive (Excite). In the CoJet Sand group, the effect of a silane coupling agent (Monobond-S) was also investigated. The repair composite (Spectrum TPH) was applied into a mould in three layers of 1 mm, each separately light-cured for 40 s. Repair tensile bond strengths were determined after 24-h storage. Mechanical and adhesive treatment had significant effects on repair bond strength (P OptiBond FL Adhesive), adhesive treatments significantly increased repair bond strengths to 6-month-old composite when compared to the controls without adhesive. Adhesive treatment of the mechanically roughened composite is essential for achieving acceptable repair bond strengths. The more complicated use of silica-coated particles for sandblasting followed by a silane coupling agent had no advantage over common bonding systems.

  2. Arthroscopic optical coherence tomography provides detailed information on articular cartilage lesions in horses.

    Science.gov (United States)

    te Moller, N C R; Brommer, H; Liukkonen, J; Virén, T; Timonen, M; Puhakka, P H; Jurvelin, J S; van Weeren, P R; Töyräs, J

    2013-09-01

    Arthroscopy enables direct inspection of the articular surface, but provides no information on deeper cartilage layers. Optical coherence tomography (OCT), based on measurement of reflection and backscattering of light, is a diagnostic technique used in cardiovascular surgery and ophthalmology. It provides cross-sectional images at resolutions comparable to that of low-power microscopy. The aim of this study was to determine if OCT is feasible for advanced clinical assessment of lesions in equine articular cartilage during diagnostic arthroscopy. Diagnostic arthroscopy of 36 metacarpophalangeal joints was carried out ex vivo. Of these, 18 joints with varying degrees of cartilage damage were selected, wherein OCT arthroscopy was conducted using an OCT catheter (diameter 0.9 mm) inserted through standard instrument portals. Five sites of interest, occasionally supplemented with other locations where defects were encountered, were arthroscopically graded according to the International Cartilage Repair Society (ICRS) classification system. The same sites were evaluated qualitatively (ICRS classification and morphological description of the lesions) and quantitatively (measurement of cartilage thickness) on OCT images. OCT provided high resolution images of cartilage enabling determination of cartilage thickness. Comparing ICRS grades determined by both arthroscopy and OCT revealed poor agreement. Furthermore, OCT visualised a spectrum of lesions, including cavitation, fibrillation, superficial and deep clefts, erosion, ulceration and fragmentation. In addition, with OCT the arthroscopically inaccessible area between the dorsal MC3 and P1 was reachable in some cases. Arthroscopically-guided OCT provided more detailed and quantitative information on the morphology of articular cartilage lesions than conventional arthroscopy. OCT could therefore improve the diagnostic value of arthroscopy in equine orthopaedic surgery.

  3. Chondrocytes, Mesenchymal Stem Cells, and Their Combination in Articular Cartilage Regenerative Medicine.

    Science.gov (United States)

    Nazempour, A; Van Wie, B J

    2016-05-01

    Articular cartilage (AC) is a highly organized connective tissue lining, covering the ends of bones within articulating joints. Its highly ordered structure is essential for stable motion and provides a frictionless surface easing load transfer. AC is vulnerable to lesions and, because it is aneural and avascular, it has limited self-repair potential which often leads to osteoarthritis. To date, no fully successful treatment for osteoarthritis has been reported. Thus, the development of innovative therapeutic approaches is desperately needed. Autologous chondrocyte implantation, the only cell-based surgical intervention approved in the United States for treating cartilage defects, has limitations because of de-differentiation of articular chondrocytes (AChs) upon in vitro expansion. De-differentiation can be abated if initial populations of AChs are co-cultured with mesenchymal stem cells (MSCs), which not only undergo chondrogenesis themselves but also support chondrocyte vitality. In this review we summarize studies utilizing AChs, non-AChs, and MSCs and compare associated outcomes. Moreover, a comprehensive set of recent human studies using chondrocytes to direct MSC differentiation, MSCs to support chondrocyte re-differentiation and proliferation in co-culture environments, and exploratory animal intra- and inter-species studies are systematically reviewed and discussed in an innovative manner allowing side-by-side comparisons of protocols and outcomes. Finally, a comprehensive set of recommendations are made for future studies.

  4. 高纯度猪软骨Ⅱ型胶原修复兔膝关节软骨缺损的实验研究%The experimental study on the repair of articular cartilage defects of the knee in rabbits with type Ⅱ collagen

    Institute of Scientific and Technical Information of China (English)

    李斯明; 杨小红; 方力; 叶春婷; 李小华; 梁佩红

    2008-01-01

    Objective To investigate the feasibility of repairing articular cartilage defects with type Ⅱ collagen prepared in our institute.Methods Forty adult male New Zealand white rabbits were used for preparing models of cartilage defects at the knee joint.The rabbits were randomly divided into 2 even groups. In Group A,the cartilage defects at the knee joint of 20 rabbits were filled with type collagen.In Group B, the cartilage defects at the knee joints of the other 20 rabbits were not treatedcontrols.The tissue samples of the kneejoint were collected and examined by H&E,Safranin 0 and Masson staining and type Ⅱ collagen immunostaining at 2,4,8,12 and 24 weeks postoperatively. Results H&E and Masson staining examinations revealed regeneration of cartilage in Group A 2 weeks postoperatively.The newborn ehondrocytes grew into the defect resion along the collagen fiber net.The new cartilage tissue filled up the whole defect region in Group A 12 weeks postoperatively,while only fibrous tissues could be found in the defect region in Group B 24 weeks postoperatively.Type Ⅱ collagen immunohistochemistry examination verified that the regenerated ehondrocytes exhibited a normal phenotype in Group A.The Safranin 0 examination also confirmed that the regenerated chondrocytes had a normal function of secreting cartilage matrix in Group A. Condusions Type Ⅱ collagen can induce regeneration of chondrecytes and promote healing of articular cartilage defects.The regenerated ehondrocytes induced by type Ⅱ collagen exhibit normal phenotype and function. Therefore,it may be a valuable stuffing biomaterial for repairing articular cartilage defects.%目的 研制高纯度猪软骨Ⅱ型胶原海绵,探讨其修复关节软骨缺损的可行性.方法 将40只成年雄性新西兰兔制成膝关节软骨缺损模型,随机分成两组.A组20只兔的缺损区植入Ⅱ型胶原海绵,B组20只兔的缺损区旷置,不植入胶原作为对照.于术后2、4、8、12、24

  5. 膝关节镜检查结合关节外微创技术对膝关节多韧带损伤的分期修复效果分析%Effect Analysis on the Staged Repair of Knee Joint Multi-ligament Injuries by Knee Arthroscopy in Combination with Extra-articular Minimally Invasive Technique

    Institute of Scientific and Technical Information of China (English)

    曹辉; 陶海; 张向阳; 叶佳; 赵迎春; 郑剑; 陶凤华

    2016-01-01

    目的:分析膝关节镜检查结合关节外微创技术对膝关节多韧带损伤的分期修复的临床效果。方法:收集2012年1月-2014年3月于笔者所在医院接受治疗的膝关节多韧带损伤患者42例(52膝),均给予膝关节镜检查结合关节外微创技术治疗,手术后均给予Lysholm与IKDC量表评分,评价膝关节修复效果。结果:Lysholm评分:平均分数为89.1分。IKDC评级:31个膝关节A级,17个膝关节B级,4个膝关节C级。Lachman试验:32个膝关节(-),16个膝关节(+),4个膝关节(++)。侧方应力试验:52个膝关节的活动度均得到有效恢复,其屈曲受限均<10°,伸直受限均<5°。52个膝关节内、外侧应力试验均表现(-)。结论:采用膝关节镜检查结合关节外微创技术治疗膝关节多韧带损伤,具有良好的临床疗效,值得临床推广应用。%Objective:To analyze the clinical effect on the staged repair of multi-ligament injuries by knee arthroscopy in combination with extra-articular minimally invasive technique.Method:A total of 42 patients(52 knee joints) with knee joint multi-ligament injuries admitted to our hospital from January 2012 to March 2014 were selected as subjects,they all received knee arthroscopy in combination with extra-articular minimally invasive technique.Lysholm scale and IKDC scale were used after operation to evaluate the repair effect of knee joint.Result:The average Lysholm score was 89.1 points.As for the IKDC grading,31 knee joints were classified as grade A,17 knee joints were classified as grade B and 4 knee joints were classified as grade C.The results of Lachman test were as follows:32 knee joints were (-),16 knee joints were (+) and 4 knee joints were (++).According to the lateral stress test,the motion range of 52 knee joints was effectively improved,with flexion limitation<10° and extension limitation<5°.All the 52 knee joints showed negative results (-) in the internal and

  6. Finite element model of distal tibial articular surface defect:Biomechanical analysis%胫骨远端关节面缺损有限元模型的生物力学分析

    Institute of Scientific and Technical Information of China (English)

    余华; 李少星; 赵长义; 闫金成

    2013-01-01

    BACKGROUND:Finite element analysis has been widely used for the research of bone and joint biomechanics, but the reports about finite element analysis of distal tibial articular surface defect are rare at home and abroad. OBJECTIVE:To establish ankle three-dimensional finite element model, produce distal tibial articular surface defects with different areas, and to simulate the distal tibial articular surface deformation and displacement under the different phases, thus predict the maximum al owable degree of distal tibial articular surface defect and explore the mechanics pathogenesis of ankle traumatic arthritis. METHODS:Continuous tomographic images were obtained by multi-slice spiral CT scan of a normal adult male ankle, and then the images were imported into the Mimics medicine modeling software to generate a entity model;the large general-purpose finite element analysis software ANSYS 13.0 was used for meshing, material property assignment and generating a finite element model. Restricted boundary conditions and simulated ankle distal end axial force, and then the stress distribution and displacement results of distal tibial articular surface in different phases were obtained. RESULTS AND CONCLUSION:The total number of units of the established finite element model of ankle joint was 157 990, and the total number of nodes was 193 801. On three phases, with the increase of the distal tibial defect area, the contact area was gradual y decreased, especial y in plantar flexion with the defect diameter of 13 mm, the change of the area was most obvious;The contact area of the neutral position was largest;with the increase of the distal tibial defect area in the neutral position and dorsiflexion, the peak stress was increased gradual y, and significantly increased after the diameter changed into 11-13 mm;in the neutral position and 10° of dorsiflexion, the peak stress mainly concentrated in the posteromedial and posterolateral quadrant;in 10° of plantar flexion

  7. Effect of different mechanical and chemical surface treatments on the repaired bond strength of an indirect composite resin.

    Science.gov (United States)

    Kimyai, Soodabeh; Oskoee, Siavash Savadi; Mohammadi, Narmin; Rikhtegaran, Sahand; Bahari, Mahmoud; Oskoee, Parnian Alizadeh; Vahedpour, Hafez

    2015-02-01

    This study compared the effects of two mechanical surface preparation techniques, air abrasion and Nd:YAG laser, with the use of two adhesive systems, self-etch and etch and rinse, on the repair bond strengths of an indirect composite resin. One hundred fifty cylindrical samples of an indirect composite resin were prepared and randomly divided into six groups (n = 25). In groups 1-3, the composite resin surfaces were respectively prepared as follows: no roughening, roughening by air abrasion, and roughening by Nd:YAG laser, followed by application of an etch-and-rinse adhesive. In groups 4-6, the preparation techniques were respectively the same as those in groups 1-3, followed by application of a self-etch adhesive. Subsequently, a direct composite resin was added and repair bond strengths were measured. Data were analyzed with two-way ANOVA and post hoc Tukey's test. Mean bond strength value was significant based on the preparation technique (P composite resin with air abrasion and Nd:YAG laser resulted in a significant increase in the repair bond strength, with air abrasion being more effective. There were no significant differences in bond strength between the two adhesives.

  8. A comparative effect of various surface chemical treatments on the resin composite-composite repair bond strength

    Directory of Open Access Journals (Sweden)

    Shaloo Gupta

    2015-01-01

    Full Text Available Aim: The aim of this in vitro study was an attempt to investigate the effect of different surface treatments on the bond strength between pre-existing composite and repair composite resin. Materials and Methods: Forty acrylic blocks were prepared in a cuboidal mould. In each block, a well of 5 mm diameter and 5 mm depth was prepared to retain the composite resin (Filtek™ Z350, 3M/ESPE. Aging of the composite discs was achieved by storing them in water at 37°C for 1 week, and after that were divided into 5 groups (n = 8 according to surface treatment: Group I- 37% phosphoric acid, Group II-10% hydrofluoric acid, Group III-30% citric acid, Group IV-7% maleic acid and Group V- Adhesive (no etchant. The etched surfaces were rinsed and dried followed by application of bonding agent (Adper™ Single Bond 2. 3M/ESPE. The repair composite was placed on aged composite, light-cured for 40 seconds and stored in water at 37°C for 1 week. Shear bond strength between the aged and the new composite resin was determined with a universal testing machine (crosshead speed of 0.5 mm/min. Statistical Analysis: The compressive shear strengths were compared for differences using ANOVA test followed by Tamhane′s T2 post hoc analysis. Results: The surface treatment with 10% hydrofluoric acid showed the maximum bond strength followed by 30% citric acid, 7% maleic acid and 37% phosphoric acid in decreasing order. Conclusion: The use of 10% hydrofluoric acid can be a good alternative for surface treatment in repair of composite resin restoration as compared to commonly used 37% orthophosphoric acid.

  9. Biomechanical characteristics of distal tibial articular surface defect of the ankle joint:three-dimensional finite element analysis%踝关节胫骨远端关节面缺损生物力学特征的三维有限元分析

    Institute of Scientific and Technical Information of China (English)

    宋作成; 闫小龙

    2016-01-01

    BACKGROUND:Studies found that three-dimensional finite element analysis can be used in the study of ankle biomechanics, but research on distal tibial articular surface defect was few. OBJECTIVE:To analyze the biomechanics of distal tibial articular surface defect with three-dimensional finite element, and provide the basis for mechanism of ankle injury related diseases. METHODS:We established ankle three-dimensional finite element model, and set different diameters of distal tibial articular surface defect, observed the peak stress of distal tibial articular surface at load of 1 400 N and the flexor of 14°, at load of 700 N and neutral position, at load 2 100 N and dorsiflexion of 10°, and contact area of tibial astragaloid joint surface at different postures and different defect diameters. RESULTS AND CONCLUSION:(1) At load of 1 400 N and plantar flexion of 14°, the distal tibial articular surface front quadrant stress peak was smal est when the distal tibial articular surface defect diameter was 8 mm, and was maximum when defect diameter was 16 mm;the distal tibial articular surface front inner quadrant stress peak was smal est when the distal tibial articular surface defect diameter was 12 mm, and maximum when defect diameter was 16 mm;the distal tibial articular surface posterior quadrant stress peak was smal est when defect diameter was 12 mm, distal tibial articular surface posterior inner quadrant stress peak was smal est when defect diameter was 0 mm;the distal tibial exterior stress peak was maximum when defect diameter was 16 mm. (2) At load of 700 N and neutral position, exterior front quadrant, front inner quadrant, posterior quadrant and posterior inner quadrant stress peaks increased with the distal tibial articular surface defect increases;the distal tibial articular surface defect stress peak was maximum when defect diameter was 16 mm. (3) At load of 2 100 N and dorsiflexion of 10°, the distal tibial articular surface stress peak was maximum

  10. Influence of surface treatment and cyclic loading on the durability of repaired all-ceramic crowns

    Directory of Open Access Journals (Sweden)

    Ahmed Attia

    2010-04-01

    Full Text Available OBJECTIVE: This study investigated the durability of repaired all-ceramic crowns after cyclic loading. MATERIAL AND METHODS: Eighty In-ceram zirconia crowns were fabricated to restore prepared maxillary premolars. Resin cement was used for cementation of crowns. Palatal cusps were removed to simulate fracture of veneering porcelain and divided into 4 groups (n = 20. Fracture site was treated before repair as follows: roughening with diamond bur, (DB; air abrasion using 50 µm Al2O3, (AA and silica coating using Cojet system followed by silane application, (SC. Control group (CG 20 specimens were left without fracture. Palatal cusps were repaired using composite resin. Specimens were stored in water bath at 37ºC for one week. Ten specimens of each group were subjected to cyclic loading. Fracture load (N was recorded for each specimen using a universal testing machine. Two-way analysis of variance (ANOVA and Tukey honestly significant difference (HSD test (a=.05 were used for statistical analysis. RESULTS: There was statistically significant difference between control and tested groups, (p<0.001. Post Hoc analysis with the Tukey HSD test showed that cyclic loading fatigue significantly decreased means fracture load of control and test groups as follows (CG, 950.4±62.6 / 872.3±87.4, P = 0.0004, (DB, 624.2 ±38 / 425.5± 31.7, P <.001, (AA, 711.5 ±15.5 / 490 ± 25.2, p <0.001 and (SC, 788.7 ± 18.1 / 610.2 ± 25.2, P <.001, while silica coating and silane application significantly increased fracture load of repaired crowns (p<0.05. CONCLUSION: Repair of fractured In-ceram zirconia crowns after chairside treatment of the fracture site by silica coating and silane application could improve longevity of repaired In-ceram zirconia crowns.

  11. Human Adipose-Derived Mesenchymal Progenitor Cells Engraft into Rabbit Articular Cartilage

    Directory of Open Access Journals (Sweden)

    Wen Wang

    2015-05-01

    Full Text Available Mesenchymal stem cells (MSCs are known to have the potential for articular cartilage regeneration, and are suggested for the treatment of osteoarthritis (OA. Here, we investigated whether intra-articular injection of xenogeneic human adipose-derived mesenchymal progenitor cells (haMPCs promoted articular cartilage repair in rabbit OA model and engrafted into rabbit articular cartilage. The haMPCs were cultured in vitro, and phenotypes and differentiation characteristics of cells were evaluated. OA was induced surgically by anterior cruciate ligament transection (ACLT and medical meniscectomy of knee joints. At six weeks following surgery, hyaluronic acid (HA or haMPCs was injected into the knee joints, the contralateral knee served as normal control. All animals were sacrificed at the 16th week post-surgery. Assessments were carried out by macroscopic examination, hematoxylin/eosin (HE and Safranin-O/Fast green stainings and immunohistochemistry. The data showed that haMPC treatment promoted cartilage repair. Signals of human mitochondrial can be directly detected in haMPC treated cartilage. The haMPCs expressed human leukocyte antigen I (HLA-I but not HLA-II-DR in vivo. These results suggest that intra-articular injection of haMPCs promotes regeneration of articular cartilage in rabbit OA model, and support the notion that MPCs are transplantable between HLA-incompatible individuals.

  12. The Application of Polysaccharide Biocomposites to Repair Cartilage Defects

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2014-01-01

    Full Text Available Owing to own nature of articular cartilage, it almost has no self-healing ability once damaged. Despite lots of restore technologies having been raised in the past decades, no repair technology has smoothly substituted for damaged cartilage using regenerated cartilage tissue. The approach of tissue engineering opens a door to successfully repairing articular cartilage defects. For instance, grafting of isolated chondrocytes has huge clinical potential for restoration of cartilage tissue and cure of chondral injury. In this paper, SD rats are used as subjects in the experiments, and they are classified into three groups: natural repair (group A, hyaluronic acid repair (group B, and polysaccharide biocomposites repair (hyaluronic acid hydrogel containing chondrocytes, group C. Through the observation of effects of repairing articular cartilage defects, we concluded that cartilage repair effect of polysaccharide biocomposites was the best at every time point, and then the second best was hyaluronic acid repair; both of them were better than natural repair. Polysaccharide biocomposites have good biodegradability and high histocompatibility and promote chondrocytes survival, reproduction, and spliting. Moreover, polysaccharide biocomposites could not only provide the porous network structure but also carry chondrocytes. Consequently hyaluronic acid-based polysaccharide biocomposites are considered to be an ideal biological material for repairing articular cartilage.

  13. 伴踝关节面损伤的胫骨下1/3骨折的治疗%Fractures of Distal Third of the Tibia with Involvement of the Articular Surface of the Ankle

    Institute of Scientific and Technical Information of China (English)

    王亚梓; 郑涛; 刘津浩; 陆宸照

    2001-01-01

    目的通过对伴有踝关节面骨折的胫骨下1/3骨折的诊断和治疗,提出闭合手术复位的固定原则。方法在34例胫骨下1/3骨折患者的髓内钉手术中,6例伴有踝关节面损伤于髓内钉手术后,经皮加用拉力螺钉固定关节面骨折片。结果经过治疗的病人均获得满意的效果,没有骨折移位皮肤坏死的并发症,踝关节功能基本正常。结论胫骨下1/3骨折伴有踝关节面损伤的病例即使手术前未发现经关节面的骨折,也要在髓内钉手术中和手术后加以排除;在胫骨的髓内钉固定手术中,无论踝关节面的骨片移位与否,都应用拉力螺钉固定。%Objective We reviewed six patients with fractures of the distal tibia and metaphyse is with displaced extension into the ankle joint, and recommended a biological surgical solution using closed locked intramedullary nailing and additional percutaneous interfragrnentary screw fixation Methods During 34 tibia intramedullary nailing operations, we found 6 patients with fractures of the distal tibial ar- ticular surface which requied additional inter-articular-fragmentary screw fixation. Results All pa- tients had good results and normal range of ankle motion. There were not fracture displacement and soft tissue complications. Conclusion Fractures of the distal third of the tibia may be associated with articu- lar fracture which may be neglected. We must examine the ankle carefully at operation and post operation. Fractures of the distal tibia involving the articular surface with or without displacement should be fixed by lag screws during operation.

  14. Quantitative assessment of optical properties in healthy cartilage and repair tissue by optical coherence tomography and histology (Conference Presentation)

    Science.gov (United States)

    Jansen, Sanne M. A.; Cernohorsky, Paul; de Bruin, Daniel M.; van der Pol, Edwin; Savci-Heijink, Cemile D.; Strackee, Simon D.; Faber, Dirk J.; van Leeuwen, Ton G.

    2016-02-01

    Quantification of the OCT signal is an important step toward clinical implementation of a diagnostic tool in cartilage imaging. Discrimination of structural cartilage differences in patients with osteoarthritis is critical, yet challenging. This study assesses the variation in the optical attenuation coefficient (μOCT) between healthy cartilage, repair tissue, bone and layers within repair tissue in a controlled setting. OCT and histology was used to assess goat talus articular surfaces in which central osteochondral defects were created. Exact matches of OCT and histology were selected for research. μOCT measurements were taken from healthy cartilage, repair tissue and bone. Measured μOCT in healthy cartilage was higher compared to both repair tissue and bone tissue. Two possible mechanisms for the difference in attenuation were investigated. We studied morphological parameters in terms of nucleus count, nucleus size and inter-nucleus distance. Collagen content in healthy cartilage and repair tissue was assessed using polarization microscopy. Quantitative analysis of the nuclei did not demonstrate a difference in nucleus size and count between healthy cartilage and repair tissue. In healthy cartilage, cells were spaced farther apart and had a lower variation in local nuclear density compared to repair tissue. Polarization microscopy suggested higher collagen content in healthy cartilage compared to repair tissue. μOCT measurements can distinguish between healthy cartilage, repair tissue and bone. Results suggest that cartilage OCT attenuation measurements could be of great impact in clinical diagnostics of osteoarthritis.

  15. Enhanced cartilage repair in ‘healer’ mice—New leads in the search for better clinical options for cartilage repair

    Science.gov (United States)

    Fitzgerald, Jamie

    2016-01-01

    Adult articular cartilage has a poor capacity to undergo intrinsic repair. Current strategies for the repair of large cartilage defects are generally unsatisfactory because the restored cartilage does not have the same resistance to biomechanical loading as authentic articular cartilage and degrades over time. Recently, an exciting new research direction, focused on intrinsic cartilage regeneration rather than fibrous repair by external means, has emerged. This review explores the new findings in this rapidly moving field as they relate to the clinical goal of restoration of structurally robust, stable and non-fibrous articular cartilage following injury. PMID:27130635

  16. Mapping the Articular Contact Area of the Long Head of the Biceps Tendon on the Humeral Head

    Directory of Open Access Journals (Sweden)

    Brent J. Morris

    2014-01-01

    Full Text Available The purpose of this investigation was to calculate the contact surface area of the long head of the biceps (LHB in neutral position and abduction. We sought to determine whether the LHB articulates with the humeral head in a consistent pattern comparing articular contact area in neutral position and abduction. Eleven fresh frozen matched cadaveric shoulders were analyzed. The path of the biceps tendon on the articular surface of the humeral head and the total articular surface were digitized using a MicronTracker 2 H3-60 three-dimensional optical tracker. Contact surface area was significantly less in abduction than in neutral position (P=0.002 with a median ratio of 41% (36%, 47.5%. Ratios of contact area in neutral position to full articular surface area were consistent between left and right shoulders (rho=1, P=0.017 as were ratios of abduction area to full articular surface area (rho= 0.97, P=0.005. The articular contact surface area is significantly greater in neutral position than abduction. The ratios of articular contact surface areas to total humeral articular surface areas have a narrow range and are consistent between left and right shoulders of the same cadaver.

  17. Contact characteristics of articular surfaces for talus during gait-a finite element analysis%正常步态下距骨关节面接触特征的有限元分析

    Institute of Scientific and Technical Information of China (English)

    卢昌怀; 余斌; 陈辉强; 林庆荣

    2011-01-01

    [目的]通过有限元法分析正常步态下距骨各关节面软骨应力变化,了解各关节面软骨应力分布的生物力学特征.[方法]利用正常男性的足踝部螺旋 CT 扫描数据,运用三维建模软件,建立足踝部三维几何模型,并对其进行有限元网格划分,分析正常步态下距骨各关节面接触应力及 Von Mises 应力分布.[结果]建立包括骨、软骨、韧带在内的正常人体足踝部三维有限元模型,共21 865 个节点、73 440 个单元,较客观地反映了人体足踝的解剖结构和力学特性.不同位相距骨各关节面接触应力及 Von Mises 应力分布区域和应力值不同.[结论]采用有限元法分析关节软骨应力的生物力学特征是一种可行、有效的方法.%[ Objective] To construct a three- dimensional finite element model (FEM) of normal adult human ankle in order to supply a digital platform for biomechanical research of talar cartilage stress during gait, and understand the stress distribution of cartilage biomechanical characteristics. [ Methods] A three - dimensional FEM of normal adult human ankle was established through helical CT images and meshed, for analysis of contact pressure and Von Mises stress distribution of cartilage during gait. [ Results] An ankle model was constructed including bones, cartilage, ligaments, which was composed of 21 865 nodes, 73 440 elements. The articular surface contact stress and the Von Mises stress distribution and stress values were different in different stance phases. [ Conclusion] The application of FEM is valid and reasonable. It could be optimized by the interference of anatomical data and biomechanical experiments and used in further articular cartilage biomechanics research.

  18. Autologous chondrocyte implantation: superior biologic properties of hyaline cartilage repairs.

    Science.gov (United States)

    Henderson, Ian; Lavigne, Patrick; Valenzuela, Herminio; Oakes, Barry

    2007-02-01

    Information regarding the quality of autologous chondrocyte implantation repair is needed to determine whether the current autologous chondrocyte implantation surgical technology and the subsequent biologic repair processes are capable of reliably forming durable hyaline or hyaline-like cartilage in vivo. We report and analyze the properties and qualities of autologous chondrocyte implantation repairs. We evaluated 66 autologous chondrocyte implantation repairs in 57 patients, 55 of whom had histology, indentometry, and International Cartilage Repair Society repair scoring at reoperation for mechanical symptoms or pain. International Knee Documentation Committee scores were used to address clinical outcome. Maximum stiffness, normalized stiffness, and International Cartilage Repair Society repair scoring were higher for hyaline articular cartilage repairs compared with fibrocartilage, with no difference in clinical outcome. Reoperations revealed 32 macroscopically abnormal repairs (Group B) and 23 knees with normal-looking repairs in which symptoms leading to arthroscopy were accounted for by other joint disorders (Group A). In Group A, 65% of repairs were either hyaline or hyaline-like cartilage compared with 28% in Group B. Autologous chondrocyte repairs composed of fibrocartilage showed more morphologic abnormalities and became symptomatic earlier than hyaline or hyaline-like cartilage repairs. The hyaline articular cartilage repairs had biomechanical properties comparable to surrounding cartilage and superior to those associated with fibrocartilage repairs.

  19. Ruidos articulares en estudiantes universitarios

    OpenAIRE

    Mafla-Chamorro, Ana Cristina; Zambrano-Muñoz, Diana Carolina; Gómez-Díaz, Yeimy; Dorado-Díaz, Luz Andrea; Bastidas-Eraso, Carlos Eduardo; Chicaiza, Oswaldo Esteban

    2014-01-01

    Introducción: determinar la prevalencia de ruidos articulares en estudiantes universitarios de 20 años de edad en San Juan de Pasto, Nariño, Colombia. Métodos: la muestra consistió de 173 individuos (77 hombres y 96 mujeres), quienes fueron evaluados de acuerdo con los Criterios Diagnósticos para la Investigación de Trastornos Temporomandibulares (RDC/TMD versión española) Eje I. Resultados: 36 individuos (20,8%) tuvieron ruidos articulares; 32 (18,8%) fueron clicking y 4 (2%), crepitación. L...

  20. Similar hyaline-like cartilage repair of osteochondral defects in rabbits using isotropic and anisotropic collagen scaffolds.

    Science.gov (United States)

    de Mulder, Eric L W; Hannink, Gerjon; van Kuppevelt, Toin H; Daamen, Willeke F; Buma, Pieter

    2014-02-01

    Lesions in knee joint articular cartilage (AC) have limited repair capacity. Many clinically available treatments induce a fibrous-like cartilage repair instead of hyaline cartilage. To induce hyaline cartilage repair, we hypothesized that type I collagen scaffolds with fibers aligned perpendicular to the AC surface would result in qualitatively better tissue repair due to a guided cellular influx from the subchondral bone. By specific freezing protocols, type I collagen scaffolds with isotropic and anisotropic fiber architectures were produced. Rabbits were operated on bilaterally and two full thickness defects were created in each knee joint. The defects were filled with (1) an isotropic scaffold, (2) an anisotropic scaffold with pores parallel to the cartilage surface, and (3) an anisotropic scaffold with pores perpendicular to the cartilage surface. Empty defects served as controls. After 4 (n=13) and 12 (n=13) weeks, regeneration was scored qualitatively and quantitatively using histological analysis and a modified O'Driscoll score. After 4 weeks, all defects were completely filled with partially differentiated hyaline cartilage tissue. No differences in O'Driscoll scores were measured between empty defects and scaffold types. After 12 weeks, all treatments led to hyaline cartilage repair visualized by increased glycosaminoglycan staining. Total scores were significantly increased for parallel anisotropic and empty defects over time (phyaline-like cartilage repair. Fiber architecture had no effect on cartilage repair.

  1. One-stage vs two-stage cartilage repair: a current review

    Directory of Open Access Journals (Sweden)

    Daniel Meyerkort

    2010-10-01

    Full Text Available Daniel Meyerkort, David Wood, Ming-Hao ZhengCenter for Orthopaedic Research, School of Surgery and Pathology, University of Western Australia, Perth, AustraliaIntroduction: Articular cartilage has a poor capacity for regeneration if damaged. Various methods have been used to restore the articular surface, improve pain, function, and slow progression to osteoarthritis.Method: A PubMed review was performed on 18 March, 2010. Search terms included “autologous chondrocyte implantation (ACI” and “microfracture” or “mosaicplasty”. The aim of this review was to determine if 1-stage or 2-stage procedures for cartilage repair produced different functional outcomes.Results: The main procedures currently used are ACI and microfracture. Both first-generation ACI and microfracture result in clinical and functional improvement with no significant differences. A significant increase in functional outcome has been observed in second-generation procedures such as Hyalograft C, matrix-induced ACI, and ChondroCelect compared with microfracture. ACI results in a higher percentage of patients with clinical improvement than mosaicplasty; however, these results may take longer to achieve.Conclusion: Clinical and functional improvements have been demonstrated with ACI, microfracture, mosaicplasty, and synthetic cartilage constructs. Heterogeneous products and lack of good-quality randomized-control trials make product comparison difficult. Future developments involve scaffolds, gene therapy, growth factors, and stem cells to create a single-stage procedure that results in hyaline articular cartilage.Keywords: autologous chondrocyte implantation, microfracture, cartilage repair

  2. Charpy Impact Response of the Cracked Aluminum Plates Repaired with FML Patches using the Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Faramarz Ashenai Ghasemi

    2016-09-01

    Full Text Available Here, the effect of fiber metal laminate (FMLs patches was studied for repairing of single-sided cracked aluminum plates experimentally to see their response to Charpy impact tests. The main desired parameters were composite patch lay-up, crack length, and crack angle each one in three levels. All experimental attempts generated and followed based on the design of experiments method by using of response surface methodology. The predicted energy absorption values obtained from the model were in good agreement with the experimental results. No matter the specimens were repaired or not, as the crack length was increased the energy absorption of the structure was decreased. The experimental results also showed that for lengthen cracks, increasing of the crack angle had more effect on energy absorption. Also it was observed that the patch lay-up effective on the impact response of the specimens. The more the metal layer was departed from the aluminum plate and the FML patches interfacial surface, the less energy was absorbed in the structure.

  3. 壳聚糖水凝胶复合脂肪间充质干细胞修复兔关节软骨缺损%Chitosan hydrogel composite with adipose-derived stem cells for repair of rabbit articular cartilage defect

    Institute of Scientific and Technical Information of China (English)

    林涛; 陈竹; 袁德超; 刘康; 向小聪; 周玉川; 冯刚

    2016-01-01

    Objective To fabricate a novel tissue-engineered cartilage with adipose-derived stem cells (ADSCs) seeded on the chitosan hydrogel scaffold to repair articular cartilage defect.Methods Adipose tissue and costal cartilage were harvested from New Zealand rabbits,and ADSCs in passage one and chondrocytes were obtained after the samples were digested and cultured in vitro.ADSCs were digested,suspended,seeded onto the sterile chitosan gel,and cultured in vitro for 1 week to fabricate the tissue-engineered cartilage.The defects were respectively filled with the tissue-engineered cartilage (composite group),chondrocyte suspension (cell group),chitosan gel (material group) and nothing at all (control group).At postoperative 12 weeks,cartilage repair was evaluated using the gross examination,histological staining,immunohistochemical staining and international cartilage repair society (ICRS) histological score.Results Effect of cartilage repair in composite group was significantly better compared to other groups.The regenerated tissue in composite group seemed tightly bound in normal tissue,with similar structure and extracellular matrix secretion.ICRS histological score in composite group was (13.89 ± 0.14) points,which differed significantly from (7.06 ± 0.19) points in control group,(7.14 ± 0.22) points in cell group and (7.46 ± 0.26) points in material group (P <0.01).Conclusion The tissue-engineered cartilage with ADSCs seeded onto the chitosan hydrogel is effective for repair of articular cartilage defect.%目的 探讨利用脂肪间充质干细胞(ADSCs)复合壳聚糖水凝胶支架构建的组织工程软骨修复兔关节软骨缺损的效果. 方法 分别取新西兰大白兔皮下脂肪和肋软骨,消化后体外扩增培养分别得到P1代ADSCs和软骨细胞.将ADSCs消化后制成细胞悬液,并种植于灭菌后的壳聚糖水凝胶上,体外培养1周构建组织工程软骨,将构建的组织工程软骨植入到兔的关节软骨缺损处.实

  4. Cartilage repair and joint preservation: medical and surgical treatment options.

    Science.gov (United States)

    Madry, Henning; Grün, Ulrich Wolfgang; Knutsen, Gunnar

    2011-10-01

    Articular cartilage defects are most often caused by trauma and osteoarthritis and less commonly by metabolic disorders of the subchondral bone, such as osteonecrosis and osteochondritis dissecans. Such defects do not heal spontaneously in adults and can lead to secondary osteoarthritis. Medications are indicated for symptomatic relief. Slow-acting drugs in osteoarthritis (SADOA), such as glucosamine and chondroitin, are thought to prevent cartilage degeneration. Reconstructive surgical treatment strategies aim to form a repair tissue or to unload compartments of the joint with articular cartilage damage. In this article, we selectively review the pertinent literature, focusing on original publications of the past 5 years and older standard texts. Particular attention is paid to guidelines and clinical studies with a high level of evidence, along with review articles, clinical trials, and book chapters. There have been only a few randomized trials of medical versus surgical treatments. Pharmacological therapies are now available that are intended to treat the cartilage defect per se, rather than the associated symptoms, yet none of them has yet been shown to slow or reverse the progression of cartilage destruction. Surgical débridement of cartilage does not prevent the progression of osteoarthritis and is thus not recommended as the sole treatment. Marrow-stimulating procedures and osteochondral grafts are indicated for small focal articular cartilage defects, while autologous chondrocyte implantationis mainly indicated for larger cartilage defects. These surgical reconstructive techniques play a lesser role in the treatment of osteoarthritis. Osteotomy near the knee joint is indicated for axial realignment when unilateral osteoarthritis of the knee causes axis deviation. Surgical reconstructive techniques can improve joint function and thereby postpone the need for replacement of the articular surface with an artificial joint.

  5. Postnatal development of articular cartilage

    NARCIS (Netherlands)

    Turnhout, van M.C.

    2010-01-01

    Articular cartilage (AC) is the thin layer of tissue that covers the ends of the bones in the synovial joints in mammals. Functional adult AC has depth-dependent mechanical properties that are not yet present at birth. These depth-dependent mechanical properties in adult life are the result of a

  6. Postnatal development of articular cartilage

    NARCIS (Netherlands)

    Turnhout, van M.C.

    2010-01-01

    Articular cartilage (AC) is the thin layer of tissue that covers the ends of the bones in the synovial joints in mammals. Functional adult AC has depth-dependent mechanical properties that are not yet present at birth. These depth-dependent mechanical properties in adult life are the result of a dep

  7. 不同材料人工髋关节关节面磨损对无菌性松动的影响%Effect of articular surface wear of different-material artificial hip joints on aseptic loosening

    Institute of Scientific and Technical Information of China (English)

    肖瑾瑛; 肖小燕; 唐方根; 刘建庭

    2011-01-01

    目的:分析各种人工髋关节假体材料在实际应用中的优势和存在的问题,对不同材料人工髋关节关节面的磨损对无菌性松动的影响进行评价.方法:以"生物材料,人工髋关节,假体,髋关节表面置换"为中文关键词,"biological materials,hip,prosthesis,hip resurfacing"为英文关键词,采用计算机检索1990-01/2009-12相关文章.纳入与不同材料人工髋关节关节面的磨损对无菌性松动的影响相关的文章;排除重复研究或Meta分析类文章.结果:人工髋关节的寿命和关节面的磨损密切相关,人工髋关节置换在临床应用研究过程中,出现无菌性松动等问题,这些问题的产生不但与假体的设计有关,而且与假体所用材料有着密切的关系,比较了不同人工髋关节假体材料的性能,为临床选择一种具耐磨损、生物相容性好的理想人工髋关节假体材料提供依据.结论:髋关节假体材料的表面改性和人体髋关节生物摩擦行为是未来研究的热点,髋关节假体材料性能评价体系的完善是亟待解决的问题.%OBJECTIVE: To analyze the advantage and problems of artificial hip joints made of different materials in clinical applications, andto evaluate the effects of articular surface wear on aseptic loosening.METHODS: A computer search of relevant articles published from January 1990 to December 2009 was performed by using thekeywords of “biological materials, hip, prosthesis, hip resurfacing” in Chinese and English. Repetitive studies or Meta analysis wereexcluded.RESULTS: The life of artificial hip joints is closely related to the articular surface wear. The appearance of aseptic loosening is notonly related to the design of prostheses, but also associated with prosthetic materials. Based on the comparison of different hipprosthesis material properties, we provide the basis for the selection of an ideal hip prosthesis material with good wear resistanceand biocompatibility

  8. Photographic-Based Optical Evaluation of Tissues and Biomaterials Used for Corneal Surface Repair: A New Easy-Applied Method.

    Directory of Open Access Journals (Sweden)

    Miguel Gonzalez-Andrades

    Full Text Available Tissues and biomaterials used for corneal surface repair require fulfilling specific optical standards prior to implantation in the patient. However, there is not a feasible evaluation method to be applied in clinical or Good Manufacturing Practice settings. In this study, we describe and assess an innovative easy-applied photographic-based method (PBM for measuring functional optical blurring and transparency in corneal surface grafts.Plastic compressed collagen scaffolds (PCCS and multilayered amniotic membranes (AM samples were optically and histologically evaluated. Transparency and image blurring measures were obtained by PBM, analyzing photographic images of a standardized band pattern taken through the samples. These measures were compared and correlated to those obtained applying the Inverse Adding-Doubling (IAD technique, which is the gold standard method.All the samples used for optical evaluation by PBM or IAD were histological suitable. PCCS samples presented transmittance values higher than 60%, values that increased with increasing wavelength as determined by IAD. The PBM indicated that PCCS had a transparency ratio (TR value of 80.3 ± 2.8%, with a blurring index (BI of 50.6 ± 4.2%. TR and BI obtained from the PBM showed a high correlation (ρ>|0.6| with the diffuse transmittance and the diffuse reflectance, both determined using the IAD (p<0.005. The AM optical properties showed that there was a largely linear relationship between the blurring and the number of amnion layers, with more layers producing greater blurring.This innovative proposed method represents an easy-applied technique for evaluating transparency and blurriness of tissues and biomaterials used for corneal surface repair.

  9. Arthroscopic Bony Bankart Repair Using Double-Threaded Headless Screw: A Case Report

    Directory of Open Access Journals (Sweden)

    Takeshi Kokubu

    2012-01-01

    Full Text Available We present a case of arthroscopic fixation for bony Bankart lesion using a double-threaded cannulated screw. A 39-year-old man sustained a left shoulder injury from a motorcycle accident. Radiographs showed bony Bankart lesion and CT revealed 40% defect of glenoid articular surface. Arthroscopic fixation was performed using double-threaded cannulated screw after the bony fragment was reduced by suturing the labrum at the edge with a suture anchor. Arthroscopic bony Bankart repair using double-threaded cannulated screw fixation is effective because compression force could be applied between bony fragments and the screw head is not exposed in the glenohumeral joint.

  10. Effect of surface conditioning modalities on the repair bond strength of resin composite to the zirconia core / veneering ceramic complex.

    Science.gov (United States)

    Ozcan, Mutlu; Valandro, Luiz Felipe; Pereira, Sarina Maciel; Amaral, Regina; Bottino, Marco Antonio; Pekkan, Gurel

    2013-06-01

    This study evaluated the effect of different surface conditioning protocols on the repair strength of resin composite to the zirconia core / veneering ceramic complex, simulating the clinical chipping phenomenon. Forty disk-shaped zirconia core (Lava Zirconia, 3M ESPE) (diameter: 3 mm) specimens were veneered circumferentially with a feldspathic veneering ceramic (VM7, Vita Zahnfabrik) (thickness: 2 mm) using a split metal mold. They were then embedded in autopolymerizing acrylic with the bonding surfaces exposed. Specimens were randomly assigned to one of the following surface conditioning protocols (n = 10 per group): group 1, veneer: 4% hydrofluoric acid (HF) (Porcelain Etch) + core: aluminum trioxide (50-µm Al2O3) + core + veneer: silane (ESPE-Sil); group 2: core: Al2O3 (50 µm) + veneer: HF + core + veneer: silane; group 3: veneer: HF + core: 30 µm aluminum trioxide particles coated with silica (30 µm SiO2) + core + veneer: silane; group 4: core: 30 µm SiO2 + veneer: HF + core + veneer: silane. Core and veneer ceramic were conditioned individually but no attempt was made to avoid cross contamination of conditioning, simulating the clinical intraoral repair situation. Adhesive resin (VisioBond) was applied to both the core and the veneer ceramic, and resin composite (Quadrant Posterior) was bonded onto both substrates using polyethylene molds and photopolymerized. After thermocycling (6000 cycles, 5°C-55°C), the specimens were subjected to shear bond testing using a universal testing machine (1 mm/min). Failure modes were identified using an optical microscope, and scanning electron microscope images were obtained. Bond strength data (MPa) were analyzed statistically using the non-parametric Kruskal-Wallis test followed by the Wilcoxon rank-sum test and the Bonferroni Holm correction (α = 0.05). Group 3 demonstrated significantly higher values (MPa) (8.6 ± 2.7) than those of the other groups (3.2 ± 3.1, 3.2 ± 3, and 3.1 ± 3.5 for groups 1, 2, and 4

  11. Toward patient-specific articular contact mechanics.

    Science.gov (United States)

    Ateshian, Gerard A; Henak, Corinne R; Weiss, Jeffrey A

    2015-03-18

    The mechanics of contacting cartilage layers is fundamentally important to understanding the development, homeostasis and pathology of diarthrodial joints. Because of the highly nonlinear nature of both the materials and the contact problem itself, numerical methods such as the finite element method are typically incorporated to obtain solutions. Over the course of five decades, we have moved from an initial qualitative understanding of articular cartilage material behavior to the ability to perform complex, three-dimensional contact analysis, including multiphasic material representations. This history includes the development of analytical and computational contact analysis methods that now provide the ability to perform highly nonlinear analyses. Numerical implementations of contact analysis based on the finite element method are rapidly advancing and will soon enable patient-specific analysis of joint contact mechanics using models based on medical image data. In addition to contact stress on the articular surfaces, these techniques can predict variations in strain and strain through the cartilage layers, providing the basis to predict damage and failure. This opens up exciting areas for future research and application to patient-specific diagnosis and treatment planning applied to a variety of pathologies that affect joint function and cartilage homeostasis.

  12. Horizontal intra-articular patellar dislocation resulting in quadriceps avulsion and medial patellofemoral ligament tear: a case report.

    Science.gov (United States)

    Kramer, Dennis E; Simoni, Michael K

    2013-07-01

    Intra-articular patellar dislocations are rare. We present a 13-year-old boy who sustained a complete horizontal intra-articular patellar dislocation following blunt trauma to the flexed knee. Closed reduction was unsuccessful and open reduction indicated a repairable quadriceps avulsion and medial patellofemoral ligament tear. He is the youngest patient to sustain a quadriceps rupture and the only patient to sustain a medial patellofemoral ligament tear to date. His flexed knee and the horizontally positioned patella (seen on lateral radiograph) were indicative of a complete rotational injury with extensor mechanism involvement. Open reduction allowed for the repair of both injuries and a favorable outcome.

  13. 骨形态发生蛋白、碱性成纤维细胞生长因子生物材料在关节软骨缺损修复中的生物性能%Biological properties of bone morphogenetic proteins and basic fibroblast growth factor in biological materials for repair of articular cartilage defect

    Institute of Scientific and Technical Information of China (English)

    董君博

    2016-01-01

    BACKGROUND:Articular cartilage regeneration can be regulatedbyautocrineorparacrinesecretionof various cytokines. OBJECTIVE:To analyze biological properties of bone morphogenetic proteins and basic fibroblast growth factor in biological materials for repair of articular cartilage defect. METHODS:Forty New Zealand white rabbits were used and equaly randomized intofourgroups: fibrin, basic fibroblast growth factor, bone morphogenetic protein, and combined treatment (basic fibroblast growth factor combined with bone morphogenetic protein) groups, respectively.Bioactivescaffolds with fibrin, basic fibroblast growth factor,bone morphogenetic protein, and basic fibroblast growth factor combined with bone morphogenetic protein were injected to repair the articular cartilage defect. Therapeutic effect andbiological properties of biological materials were compared. RESULTS AND CONCLUSION:(1) Inthefibrin group,tworabbits appearedto havelimps. Inthebasic fibroblast growth factor group hand functionwaslimited inonerabbit. Inthebone morphogenetic protein group, one had a limpandonewasin a limitation of activity. Inthecombined treatment group,rabbitsrecovered wel andshowedno differencesintheknee joint before and aftersurgery (P  目的:分析骨形态发生蛋白、碱性成纤维细胞生长因子生物材料在关节软骨缺损修复中的生物性能。  方法:选取40只新西兰家兔,随机分为4组,纤维蛋白组、碱性成纤维细胞生长因子组、骨形态发生蛋白组、复合组(骨形态发生蛋白+碱性成纤维细胞生长因子),每组10只。建立兔关节软骨缺损模型,止血彻底后将纤维蛋白、碱性成纤维细胞生长因子、骨形态发生蛋白以及骨形态发生蛋白、碱性成纤维细胞生长因子复合等材料组成的支架分别植入缺损部位。比较不同注射材料在家兔关节软骨缺损中的效果及复合材料的生物性能。  结果与结论:①关节软骨缺损修复情

  14. A novel collagen film with micro-rough surface structure for corneal epithelial repair fabricated by freeze drying technique

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yang [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China); Ren, Li, E-mail: psliren@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China); Wang, Yingjun, E-mail: imwangyj@163.com [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China)

    2014-05-01

    Highlights: • Collagen film with micro-rough surface is fabricated by freeze drying technique. • The film has suitable water uptake capability and toughness performance. • The film has good optical performance. • Human corneal epithelial cells studies confirmed the biocompatibility of the film. - Abstract: Corneal epithelial defect is a common disease and keratoplasty is a common treatment method. A collagen film with micro-rough surface was fabricated through a simple freeze drying technique in this study. Compared with the air-dried collagen film (AD-Col), this freeze-dried collagen film (FD-Col) has a more suitable water uptake capability (about 85.5%) and toughness performance. Both of the two films have good optical properties and the luminousness of them is higher than 80%. Besides, the adhesion and proliferation rate of human corneal epithelial cells on the micro-rough surface of FD-Col film is higher than that on the smooth surface of AD-Col film. The results indicate that this FD-Col film may have potential applications for corneal epithelial repair.

  15. Lubrication of Articular Cartilage.

    Science.gov (United States)

    Jahn, Sabrina; Seror, Jasmine; Klein, Jacob

    2016-07-11

    The major synovial joints such as hips and knees are uniquely efficient tribological systems, able to articulate over a wide range of shear rates with a friction coefficient between the sliding cartilage surfaces as low as 0.001 up to pressures of more than 100 atm. No human-made material can match this. The means by which such surfaces maintain their very low friction has been intensively studied for decades and has been attributed to fluid-film and boundary lubrication. Here, we focus especially on the latter: the reduction of friction by molecular layers at the sliding cartilage surfaces. In particular, we discuss such lubrication in the light of very recent advances in our understanding of boundary effects in aqueous media based on the paradigms of hydration lubrication and of the synergism between different molecular components of the synovial joints (namely hyaluronan, lubricin, and phospholipids) in enabling this lubrication.

  16. Strategies for Zonal Cartilage Repair using Hydrogels

    NARCIS (Netherlands)

    Klein, Travis J.; Rizzi, Simone C.; Reichert, Johannes C.; Georgi, Nicole; Malda, Jos; Schuurman, Wouter; Crawford, Ross W.; Hutmacher, Dietmar W.

    2009-01-01

    Articular cartilage is a highly hydrated tissue with depth-dependent cellular and matrix properties that provide low-friction load bearing in joints. However, the structure and function are frequently lost and there is insufficient repair response to regenerate high-quality cartilage. Several hydrog

  17. Classification of primary articular chondrocalcinosis.

    Science.gov (United States)

    Zitnan, D; Sitaj, S

    1979-01-01

    Based on long-term observations the authors submit a categorization of primary (hereditary and solitary) articular chondrocalcinosis into three different sub-populations. Attention is drawn to the fact that the extent of the qualitative disorder of the articular cartilage, obviously conditioned genetically, is linked with the age factor and determines the quantitative differences of pyrophosphate arthropathy in primary chondrocalcinosis. In young age, as a rule in the third decade, severe polyarticular condrocalcinosis (first sub-population) develops which causes relatively soon invalidity, in middle age (5th and 6th decade) milder condrocalcinosis develops (second sub-population) which combines with extraarticular, tendinous and tissue calcifacations, and finally in advanced age oligoarticular chondrocalcinosis develops (third sub-population) which is usually associated with ankylosing hyperostosis of the spine. Articular chondrocalcinosis (CCA) which we described by this term as a special metabolic arthropathy which occurs in families and solitary and which we defined as a special nosological unit (35, 36,) has become generally known and firmly established in rheumatology. As ensues from numerous publications, primary (idiopathic) CCA which comprises the hereditary and solitary (sporadic) form is characterized by pyrophosphate arthropathy which develops on articular cartilages not damaged by another process (13, 25, 26, 37); on the other hand as secondary CCA we consider pyrophosphate arthropathies which are associated with metabolic, endocrine or other diseases (9, 30). The common sign of both basic forms of CCA is the presence of microcrystals of calcium pyrophosphate dihydrate (CaPD) in articular cartilages, synovial fluid, or other articular structures (capsules, tendons, ligaments), characterized originally by McCarty et al. (11, 18) and later by other authors (2, 23, 27, 32). In addition to semantic (terminological) problems there were also questions of the

  18. Analysis of self-repair films on friction surface lubricated with nano-Cu additive

    Institute of Scientific and Technical Information of China (English)

    LIU Qian; XU Yi; SHI Pei-jing; YU He-long; XU Bin-shi

    2005-01-01

    The surface modified nanocopper particles were prepared with chemical reduction method. The wear test was carried out on a T-11 ball-on-plate friction and wear tester made in Poland. The material of the upper sample was GCr15 and the counterpart was AISI-1045 steel. The morphologies of the worn surfaces of the samples were observed by optical microscope and scanning electron microscope, while the element distributions on the worn surfaces were determined by means of electron microprobe analysis. As the results, a film mainly made of Cu is formed on the worn surface. The film on the surface of the still upper sample is thicker than that formed on the revolving coun terpart. At the edge of the groove of the worn surface made by the milling before test there is Cu element observed obviously, but there is not any Cu element in the bottom of the groove. A possible action mechanism of the film is suggested. The friction movement can induce reactivity of the metal and continuously produce activation surface. It benefits the film formed by nano-Cu in lubricant on the worn surface. Hardness and modulus of nano-Cu films were successfully measured and analyzed by the nanoindentation instrument. The results show that the hardness and modulus of the films are lower than those of the initial surface.

  19. Bioinspired self-repairing slippery surfaces with pressure-stable omniphobicity.

    Science.gov (United States)

    Wong, Tak-Sing; Kang, Sung Hoon; Tang, Sindy K Y; Smythe, Elizabeth J; Hatton, Benjamin D; Grinthal, Alison; Aizenberg, Joanna

    2011-09-21

    Creating a robust synthetic surface that repels various liquids would have broad technological implications for areas ranging from biomedical devices and fuel transport to architecture but has proved extremely challenging. Inspirations from natural nonwetting structures, particularly the leaves of the lotus, have led to the development of liquid-repellent microtextured surfaces that rely on the formation of a stable air-liquid interface. Despite over a decade of intense research, these surfaces are, however, still plagued with problems that restrict their practical applications: limited oleophobicity with high contact angle hysteresis, failure under pressure and upon physical damage, inability to self-heal and high production cost. To address these challenges, here we report a strategy to create self-healing, slippery liquid-infused porous surface(s) (SLIPS) with exceptional liquid- and ice-repellency, pressure stability and enhanced optical transparency. Our approach-inspired by Nepenthes pitcher plants-is conceptually different from the lotus effect, because we use nano/microstructured substrates to lock in place the infused lubricating fluid. We define the requirements for which the lubricant forms a stable, defect-free and inert 'slippery' interface. This surface outperforms its natural counterparts and state-of-the-art synthetic liquid-repellent surfaces in its capability to repel various simple and complex liquids (water, hydrocarbons, crude oil and blood), maintain low contact angle hysteresis (<2.5°), quickly restore liquid-repellency after physical damage (within 0.1-1 s), resist ice adhesion, and function at high pressures (up to about 680 atm). We show that these properties are insensitive to the precise geometry of the underlying substrate, making our approach applicable to various inexpensive, low-surface-energy structured materials (such as porous Teflon membrane). We envision that these slippery surfaces will be useful in fluid handling and

  20. The effect of tissue surface modification with collagenase and addition of TGF-beta 3 on the healing potential of meniscal tears repaired with tissue glues in vitro

    NARCIS (Netherlands)

    Bochynska, Agnieszka Izabela; Hannink, Gerjon; Verhoeven, Renate; Grijpma, Dirk W.; Buma, Pieter

    The aim of the current in vitro study was to investigate if tissue surface modification with collagenase and addition of the TGF-beta 3 can increase the number of cells present in meniscus tears repaired with the use of newly developed tissue adhesives based on isocyanate-terminated block

  1. Intra-articular chondroma of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Talwalkar, S.C.; Kambhampati, S.B.S.; Lang Stevenson, A.I. [Oldchurch Hospital, Romford, Essex (United Kingdom); Whitehouse, R. [Manchester University, Department of Radiology, Manchester (United Kingdom); Freemont, A. [University of Manchester, Department of Osteoarticular Pathology, Manchester (United Kingdom)

    2005-06-01

    Chondromas are tumours that develop in relation to the periosteum and, although they are common around the knee, most reports deal with soft tissue chondromas in para-articular locations or intracortical tumours in extra-articular regions. We report a rare case of an intra-articular chondroma in a 16-year-old boy of Asian origin developing in the region of the medial femoral condyle of the femur and extending into the femoral sulcus and the patellofemoral joint. (orig.)

  2. TIBIAL LANDMARKS IN ACL ANATOMIC REPAIR

    Directory of Open Access Journals (Sweden)

    M. V. Demesсhenko

    2016-01-01

    Full Text Available Purpose: to identify anatomical landmarks on tibial articular surface to serve as reference in preparing tibial canal with respect to the center of ACL footprint during single bundle arthroscopic repair.Materials and methods. Twelve frozen knee joint specimens and 68 unpaired macerated human tibia were studied using anatomical, morphometric, statistical methods as well as graphic simulation.Results. Center of the tibial ACL footprint was located 13,1±1,7 mm anteriorly from posterior border of intercondylar eminence, at 1/3 of the distance along the line connecting apexes of internal and external tubercles and 6,1±0,5 mm anteriorly along the perpendicular raised to this point.Conclusion. Internal and external tubercles, as well as posterior border of intercondylar eminence can be considered as anatomical references to determine the center of the tibial ACL footprint and to prepare bone canals for anatomic ligament repair.

  3. Cell-Based Treatment for the Management of Articular Cartilage Injuries Where Are We?

    Science.gov (United States)

    Rossy, William; Strauss, Eric

    2017-01-01

    Articular cartilage is a specialized tissue that lines the surface of joints. Injuries to articular cartilage pose challenges due to poor healing potential. Focal cartilage defects are typically the result of high impact or repetitive loads to the articular surface. They tend to occur in the younger, active population and have been shown to cause swelling, pain, and joint dysfunction. Although the natural history of these lesions has never been definitively elucidated in the literature, clinical experience suggests that if left untreated, these lesions will demonstrate an inability to heal and may lead to prolonged increased articular peak stresses, which in turn may lead to pain and significant limitations in the future. The purpose of the present review is to provide the most current treatment options for these injuries and review the literature supporting their use.

  4. [Intra-articular injection of cortisone].

    Science.gov (United States)

    Hammer, M; Schwarz, T; Ganser, G

    2015-11-01

    Intra-articular injections with glucocorticoids are standard procedures according to therapy guidelines in many rheumatic conditions. There is increasing evidence from clinical trials on the treatment of rheumatoid arthritis that more patients will attain the target of remission using a combination of systemic medication and intra-articular injections with glucocorticoids compared to systemic medication alone. Intra-articular injections with glucocorticoids play an important role in the therapeutic management of pediatric rheumatic diseases. In many countries competency in performing intra-articular injections is among the important skills necessary for certification as a specialist in rheumatology.

  5. An in vitro study of the effect of design of repair surface on the ...

    African Journals Online (AJOL)

    2013-03-23

    Mar 23, 2013 ... Materials and Methods: Sixty specimens of heat-cured acrylic resin of dimension 65 mm x 20 mm x .... to the specimen through 2.5 mm diameter hardened steel rod. .... without surface chemical treatment using ethyl acetate.

  6. Surgical management of the failed SLAP repair.

    Science.gov (United States)

    Weber, Stephen C

    2010-09-01

    Repair of superior labral tears anterior to posterior (SLAP) lesions has become an increasingly common procedure, despite the low incidence rates reported in the literature. As the incidence of these procedures increases, the surgeons will be increasingly confronted with patients with painful shoulders after SLAP repair. Persistent pain after SLAP repair is multifactorial; careful preoperative workup is necessary to elucidate the cause of pain. Simple failure of the prior SLAP repair will rarely be the cause of persistent pain. Use of tacks is especially worrisome, and suture anchor repair is preferable. Articular cartilage injuries because of either bioabsorbable or metal hardware will often create significant residual disability. Recent literature suggests that older patients may be better served by primary biceps tenodesis rather than SLAP repair.

  7. Articular Cartilage Repair Through Muscle Cell-Based Tissue Engineering

    Science.gov (United States)

    2011-03-01

    32–36). Surgically induced OAmodels may be more clinically relevant than chemically induced models with regard to the patho- physiology of OA. However...Am J Pathol 1989;135:1001–14. 33. Guingamp C, Gegout-Pottie P, Philippe L, Terlain B, Netter P, Gillet P. Mono-iodoacetate–induced experimental

  8. Articular Cartilage Repair Through Muscle Cell-Based Tissue Engineering

    Science.gov (United States)

    2010-03-01

    fferentiation of s tem c ells is also an i mportant i ssue t o c onsider e specially f or t he persistence of the regenerate cartilage. Based on these...tap water for 10 minutes and counterstained with nuclear fast red. Differentiation of MDSCs into chondrocytes. Pellets in OCT blocks were sectioned and...into Alcian blue solution for 30 minutes. The slides were rinsed with running tap water for 10 minutes and counterstained with nuclear fast red

  9. 一期获取自体脂肪干细胞复合可缓释诱导因子支架修复猪膝关节软骨缺损的初步研究%Defects of porcine articular cartilage of the knee repaired at one stage by autologous adipose-derived stem cells and collagen I scaffolds with slow-release inducing factors

    Institute of Scientific and Technical Information of China (English)

    刘宪民; 杜明昌; 刘松波; 王琪; 田竞; 陈语; 项良碧; 王洋

    2012-01-01

    Objective To investigate the feasibility of repairing at one stage defects of porcine articular cartilage of the knee with autologous adipose-derived stem cells (ADSCs) and collagen Ⅰ scaffolds with slow-release inducing factors.Methods We first made collagen Ⅰ scaffolds with slow-release inducing factors using freeze drying technology.The concentrations of slow-release inducing factors(transformation growth factor-β2,insulin-like growth factor-l) were evaluated by Elisa.The porcine ADSCs,obtained by density gradient centrifugation,were seeded onto the collagen Ⅰ scaffolds with slow-release inducing factors for in vitro culture for 3 weeks to observe the cellular distribution and secretion of type Ⅱ collagen and aggrecan within the scaffold.Porcine models of full thickness defects of the knee articular cartilage were created,7 ×7mm in size.ADSCs and collagen Ⅰ scaffolds were implanted into the cartilage defects in the experimental group (3 pigs) while micro-fractures were made in the subchondral bone and treated with absorbable membranes in the control group (3 pigs).Gross observation and histological analyses were conducted 2 and 4months after operation to assess defect healing in the 2 groups.Results The inducing factors were slowly released in the scaffolds with slowly reduced concentrations.The ADSCs distributed extensively and expressions of type Ⅱ collagen and aggrecan were observed in the scaffolds after 3-week in vitro culture.In the experimental group,edges of the articular cartilage defects were filled with reparative hyaline cartilage after 2 months,and the whole defects were repaired by the hyaline cartilage 4 months later.HE staining showed typical cartilaginous structure in the repaired area,though its cellular density was higher than in the normal cartilage.In the control group,defects were not repaired but filled with fibrous tissue.Conclusions Enough autologous porcine ADSCs can be obtained at one stage for implantation.ADSCs seeded

  10. Low-intensity pulsed ultrasound (LIPUS) and pulsed electromagnetic field (PEMF) treatments affect degeneration of cultured articular cartilage explants

    NARCIS (Netherlands)

    Tan, Lijun; Ren, Yijin; Kooten, van Theo G.; Grijpma, Dirk W.; Kuijer, Roel

    2015-01-01

    Purpose: Articular cartilage has some capacity for self-repair. Clinically used low-intensity pulsed ultrasound (LIPUS) and pulsed electromagnetic field (PEMF) treatments were compared in their potency to prevent degeneration using an explant model of porcine cartilage. Methods: Explants of porcine

  11. Sonographic evaluation of femoral articular cartilage in the knee

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sung Hwan [College of Medicine, Hallym University, Seoul (Korea, Republic of); Kong Keun Young; Chung, Hye Won; Choi, Young Ho; Song, Yeong Wook; Kang, Heung Sik [College of Medicine and the Institute of Radiation Medicine, Seoul National University, Seoul (Korea, Republic of)

    2000-06-01

    To investigate the usefulness of sonography for the evaluation of osteoarthritic articular cartilage. Ten asymptomatic volunteers and 20 patients with osteoarthritis of the knee underwent sonographic evaluation. For this, the knee was maintained of full flexion in order to expose the deep portion of femoral condylar cartilage. Both transverse and longitudinal scans were obtained in standardized planes. Sonographic images of the articular cartilages were analyzed in terms of surface sharpness, echogenicity and thickness, along with associated bone changes. Normal cartilages showed a clearly-defined surface, homogeneously low echogenicity and regular thickness. Among 20 patients, the findings for medial and lateral condyles, respectively, were as follows: poorly defined cartilage surface, 16 (80%) and ten (50%); increased echogenicity of cartilage, 17 (85%) and 16 (80%); cartilage thinning, 16 (80%) and 14 (70%) (two medial condyles demonstrated obvious cartilage thickening); the presence of thick subchondral hyperechoic bands, five (25%) and four (20%); the presence of osteophytes, 13 (65%) and 12 (60%). Sonography is a convenient and accurate modality for the evaluation of femoral articular cartilage. In particular, it can be useful for detecting early degenerative cartilaginous change and for studying such change during clinical follow-up. (author)

  12. Environmental impact of highway construction and repair materials on surface and ground waters. Case study: crumb rubber asphalt concrete.

    Science.gov (United States)

    Azizian, Mohammad F; Nelson, Peter O; Thayumanavan, Pugazhendhi; Williamson, Kenneth J

    2003-01-01

    The practice of incorporating certain waste products into highway construction and repair materials (CRMs) has become more popular. These practices have prompted the National Academy of Science, National Cooperative Highway Research Program (NCHRP) to research the possible impacts of these CRMs on the quality of surface and ground waters. State department of transportations (DOTs) are currently experimenting with use of ground tire rubber ( crumb rubber) in bituminous construction and as a crack sealer. Crumb rubber asphalt concrete (CR-AC) leachates contain a mixture of organic and metallic contaminants. Benzothiazole and 2(3H)-benzothiazolone (organic compounds used in tire rubber manufacturing) and the metals mercury and aluminum were leached in potentially harmful concentrations (exceeding toxic concentrations for aquatic toxicity tests). CR-AC leachate exhibited moderate to high toxicity for algae ( Selenastrum capriconutum) and moderate toxicity for water fleas ( Daphnia magna). Benzothiazole was readily removed from CR-AC leachate by the environmental processes of soil sorption, volatilization, and biodegradation. Metals, which do not volatilize or photochemically or biologically degrade, were removed from the leachate by soil sorption. Contaminants from CR-AC leachates are thus degraded or retarded in their transport through nearby soils and ground waters.

  13. Similar hyaline-like cartilage repair of osteochondral defects in rabbits using isotropic and anisotropic collagen scaffolds

    NARCIS (Netherlands)

    Mulder, E.L.W. de; Hannink, G.J.; Kuppevelt, T.H. van; Daamen, W.F.; Buma, P.

    2014-01-01

    Lesions in knee joint articular cartilage (AC) have limited repair capacity. Many clinically available treatments induce a fibrous-like cartilage repair instead of hyaline cartilage. To induce hyaline cartilage repair, we hypothesized that type I collagen scaffolds with fibers aligned perpendicular

  14. The Regulatory Role of Signaling Crosstalk in Hypertrophy of MSCs and Human Articular Chondrocytes.

    Science.gov (United States)

    Zhong, Leilei; Huang, Xiaobin; Karperien, Marcel; Post, Janine N

    2015-08-14

    Hypertrophic differentiation of chondrocytes is a main barrier in application of mesenchymal stem cells (MSCs) for cartilage repair. In addition, hypertrophy occurs occasionally in osteoarthritis (OA). Here we provide a comprehensive review on recent literature describing signal pathways in the hypertrophy of MSCs-derived in vitro differentiated chondrocytes and chondrocytes, with an emphasis on the crosstalk between these pathways. Insight into the exact regulation of hypertrophy by the signaling network is necessary for the efficient application of MSCs for articular cartilage repair and for developing novel strategies for curing OA. We focus on articles describing the role of the main signaling pathways in regulating chondrocyte hypertrophy-like changes. Most studies report hypertrophic differentiation in chondrogenesis of MSCs, in both human OA and experimental OA. Chondrocyte hypertrophy is not under the strict control of a single pathway but appears to be regulated by an intricately regulated network of multiple signaling pathways, such as WNT, Bone morphogenetic protein (BMP)/Transforming growth factor-β (TGFβ), Parathyroid hormone-related peptide (PTHrP), Indian hedgehog (IHH), Fibroblast growth factor (FGF), Insulin like growth factor (IGF) and Hypoxia-inducible factor (HIF). This comprehensive review describes how this intricate signaling network influences tissue-engineering applications of MSCs in articular cartilage (AC) repair, and improves understanding of the disease stages and cellular responses within an OA articular joint.

  15. The Regulatory Role of Signaling Crosstalk in Hypertrophy of MSCs and Human Articular Chondrocytes

    Directory of Open Access Journals (Sweden)

    Leilei Zhong

    2015-08-01

    Full Text Available Hypertrophic differentiation of chondrocytes is a main barrier in application of mesenchymal stem cells (MSCs for cartilage repair. In addition, hypertrophy occurs occasionally in osteoarthritis (OA. Here we provide a comprehensive review on recent literature describing signal pathways in the hypertrophy of MSCs-derived in vitro differentiated chondrocytes and chondrocytes, with an emphasis on the crosstalk between these pathways. Insight into the exact regulation of hypertrophy by the signaling network is necessary for the efficient application of MSCs for articular cartilage repair and for developing novel strategies for curing OA. We focus on articles describing the role of the main signaling pathways in regulating chondrocyte hypertrophy-like changes. Most studies report hypertrophic differentiation in chondrogenesis of MSCs, in both human OA and experimental OA. Chondrocyte hypertrophy is not under the strict control of a single pathway but appears to be regulated by an intricately regulated network of multiple signaling pathways, such as WNT, Bone morphogenetic protein (BMP/Transforming growth factor-β (TGFβ, Parathyroid hormone-related peptide (PTHrP, Indian hedgehog (IHH, Fibroblast growth factor (FGF, Insulin like growth factor (IGF and Hypoxia-inducible factor (HIF. This comprehensive review describes how this intricate signaling network influences tissue-engineering applications of MSCs in articular cartilage (AC repair, and improves understanding of the disease stages and cellular responses within an OA articular joint.

  16. Ultrasonic quantitation of superficial degradation of articular cartilage.

    Science.gov (United States)

    Saarakkala, Simo; Töyräs, Juha; Hirvonen, Jani; Laasanen, Mikko S; Lappalainen, Reijo; Jurvelin, Jukka S

    2004-06-01

    Ultrasound (US) has been suggested as a means for the quantitative detection of early osteoarthrotic changes in articular cartilage. In this study, the ability of quantitative US 2-D imaging (20 MHz) to reveal superficial changes in bovine articular cartilage after mechanical or enzymatic degradation was investigated in vitro. Mechanical degradation was induced by grinding samples against an emery paper with the grain size of 250 microm, 106 microm, 45 microm or 23 microm. For enzymatic degradation, samples were digested with collagenase, trypsin or chondroitinase ABC. Variations of the US reflection coefficient induced by the degradation were investigated. Furthermore, two novel parameters, the US roughness index (URI) and the spatial variation of the US reflection coefficient (SVR), were established to quantitate the integrity of the cartilage surface. Statistically significant decreases (p < 0.05) in US reflection coefficient were observed after mechanical degradations or enzymatic digestion with collagenase. Increases (p < 0.05) in URI were also revealed after these treatments. We conclude that quantitative US imaging may be used to detect collagen disruption and increased roughness in the articular surface. These structural damages are typical of early osteoarthrosis.

  17. Aircraft Metal Skin Repair and Honeycomb Structure Repair; Sheet Metal Work 3: 9857.02.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    The course helps students determine types of repairs, compute repair sizes, and complete the repair through surface protection. Course content includes goals, specific objectives, protection of metals, repairs to metal skin, and honeycomb structure repair. A bibliography and post-test are appended. A prerequisite for this course is mastery of the…

  18. Progression of articular cartilage degeneration after application of muscle stretch.

    Science.gov (United States)

    Dias, Carolina Náglio Kalil; Renner, Adriana Frias; dos Santos, Anderson Amaro; Vasilceac, Fernando Augusto; Mattiello, Stela Márcia

    2012-01-01

    The aim of study was to evaluate the progression of the ankle articular cartilage alterations after a post-immobilization muscle stretching. Twenty-nine Wistar rats were separated into five groups: C--control, S--stretched, SR--stretch recovery, IS--immobilized and stretched, and ISR--immobilized stretched recovery. The immobilization was maintained for 4 weeks and the left ankle was then stretched manually through a full dorsal flexion for 10 times for 60 s with a 30 s interval between each 60 s period, 7 days/week for 3 weeks. The recovery period was of 7 weeks. At the end of the experiment, the left ankles were removed, processed in paraffin, and stained in hematoxylin-eosin and safranin O. Two blinded observers evaluated the articular cartilage using the Mankin grading system (cellularity, chondrocyte cloning, and proteoglycan content) through light microscopy, and performed the morphometry (cellularity, total thickness, non-calcified thickness, and calcified thickness measures). Both the Mankin grading system and the morphometric analysis showed that the ISR group presented the most increased cellularity among the groups. The IS and SR groups showed the highest proteoglycan loss, and the ISR group showed the same content of proteoglycan observed in the C group. No significant differences were found in the chondrocyte cloning, the total cartilage thickness, the non-calcified cartilage thickness, and the calcified cartilage thickness among the groups. The results suggest that the cartilage can recover the proteoglycan loss caused by immobilization and stretching, probably because of the increased chondrocyte density. Therefore, the ankle articular cartilage responded as to repair the metabolic deficits.

  19. Hydrogels as a Replacement Material for Damaged Articular Hyaline Cartilage

    Directory of Open Access Journals (Sweden)

    Charlotte M. Beddoes

    2016-06-01

    Full Text Available Hyaline cartilage is a strong durable material that lubricates joint movement. Due to its avascular structure, cartilage has a poor self-healing ability, thus, a challenge in joint recovery. When severely damaged, cartilage may need to be replaced. However, currently we are unable to replicate the hyaline cartilage, and as such, alternative materials with considerably different properties are used. This results in undesirable side effects, including inadequate lubrication, wear debris, wear of the opposing articular cartilage, and weakening of the surrounding tissue. With the number of surgeries for cartilage repair increasing, a need for materials that can better mimic cartilage, and support the surrounding material in its typical function, is becoming evident. Here, we present a brief overview of the structure and properties of the hyaline cartilage and the current methods for cartilage repair. We then highlight some of the alternative materials under development as potential methods of repair; this is followed by an overview of the development of tough hydrogels. In particular, double network (DN hydrogels are a promising replacement material, with continually improving physical properties. These hydrogels are coming closer to replicating the strength and toughness of the hyaline cartilage, while offering excellent lubrication. We conclude by highlighting several different methods of integrating replacement materials with the native joint to ensure stability and optimal behaviour.

  20. Determination of the heating temperature of potholes surface on road pavement in the process of repairs using hot asphalt concrete mixes

    Directory of Open Access Journals (Sweden)

    Giyasov Botir Iminzhonovich

    2014-12-01

    Full Text Available In the process of roads construction the necessary transport and operational characteristics should be achieved, which depend on the quality of the applied, material and technologies. Under the loads of transport means and the influence of weather conditions on the road pavement deformations and destructions occur, which lead to worsening of transport and operational characteristics, decrease of operational life of the road and they are often the reason of road accidents. According to the data of the Strategic Research Center of "Rosgosstrah" more than 20 % of road accidents in Russia occur due to bad quality of road pavement. One of the main directions in traffic security control and prolongation of operational life for road pavement of non-rigid type is road works, as a result of which defects of pavement are eliminated and in case of timely repairs of high quality the operational life of the road increases for several years. The most widely used material for non-rigid pavement repairs is hot road concrete mixes and in case of adherence to specifications they provide high quality of works. The authors investigate the problems of hot asphalt concrete mixes for repairs of road surfaces of non-rigid type. The results of the study hot asphalt concrete mix’s temperature regimes are offered in case of repair works considering the temperature delivered to the work site and the ambient temperature depending on the type of mix and class of bitumen.

  1. Estabilidade articular: abordagem biomecânica

    OpenAIRE

    Alex Sandra Oliveira de Cerqueira Soares

    2015-01-01

    A instabilidade articular é responsável pelo desenvolvimento de lesões degenerativas incapacitantes que comprometem o desempenho funcional. Compreender os processos desenvolvidos para estabilização dinâmica articular é um desafio para pesquisadores das mais diversas áreas. O presente estudo propõe o uso da abordagem Biomecânica para reconhecer os mecanismos relacionadas ao processo de estabilização dinâmica articular, por meio de três diferentes condições experimentais. No experimento 1 foi a...

  2. The effect of different surface treatments on repair of CAD/CAM hybrid ceramic with resin composite

    Directory of Open Access Journals (Sweden)

    Özlem Acar

    2016-08-01

    Full Text Available OBJECTIVE: The aim of this study was to evaluate the shear bond strength of novel hybrid ceramic material repaired with a composite resin. MATERIALS and METHOD: CAD/CAM hybrid ceramic (VITA Enamic specimens were prepared. The bonding surface was abraded with 600, 800 and 1200 grit SiC papers, and treated with air abrasion of 50 µm alumina particles. The specimens were assigned to four groups (n=12. G1: etching with 34% phosphoric acid + bonding with Adper Single Bond 2, G2: etching with 8% hydrofluoric acid + silane application + bonding with Adper Single Bond 2, G3: etching with 34% phosphoric acid + bonding with Single Bond Universal, G4: etching with 8% hydrofluoric acid + silane application + bonding with Single Bond Universal. Composite resin was build up on pretreated specimens and light-polymerized. The specimens were thermocycled 1000 times between 5±2 °C and 55±2 °C. Shear bond strength test was done by using a universal testing machine at a 1 mm/min crosshead speed. Data were statistically analyzed with One Way ANOVA and post-hoc Tukey HSD tests. Results: Comparison of the shear bond strength among groups revealed statistically significant differences (p<0.05. No statistically significant difference was found between G1 and G3 (p=0.591. Statistically significant differences were found between G1 and G2 (p=0.024, and G1 and G4 (p=0.013. Adhesive failure was observed in all groups. Conclusion: Hydrofluoric acid etching reduced the composite resin to hybrid ceramic shear bond strength. Etching with phosphoric acid followed by bonding with Adper Single Bond 2 or Single Bond Universal positively influenced the bond strength of composite resin to hybrid ceramic.

  3. Imaging of intra-articular osteoid osteoma

    Energy Technology Data Exchange (ETDEWEB)

    Allen, S.D.; Saifuddin, A. E-mail: asaifuddin@aol.com

    2003-11-01

    Intra-articular osteoid osteoma accounts for approximately 13% of all osteoid osteomas and presents as a monoarthropathy. Radiographs commonly do not identify the nidus, and in this event, MRI is likely to be the next imaging investigation. MRI may show a variety of appearances depending upon the age of the lesion. This article illustrates the imaging features of intra-articular osteoid osteoma, with emphasis on MRI. CT remains the investigation of choice for identifying the nidus.

  4. Incisuroplastia troclear e estabilização articular após transecção do ligamento cruzado cranial: Estudo clínico e radiográfico em cães Intercondylar notchplasty and fascial strip repair following transection of the cranial cruciate ligament: Clinical and radiographic aspects in the dog

    Directory of Open Access Journals (Sweden)

    André Luis Selmi

    2007-10-01

    Full Text Available Avaliaram-se as alterações clínicas e radiográficas em nove cães adultos, após a transecção do ligamento cruzado cranial (LCCr seguida da substituição ligamentar por retalho de fáscia lata, associada ou não à incisuroplastia troclear (ITR. O joelho direito (GI foi submetido à ITR e posterior estabilização articular, e o esquerdo somente à substituição ligamentar (GC. Os animais foram avaliados nos períodos pré-operatório, pós-operatório (po imediato e aos 30, 90 e 180 dias de po, período coincidente com o momento de eutanásia de subgrupos de três cães. A instabilidade articular e o grau de claudicação diminuíram significativamente durante o período de avaliação, apesar da instabilidade persistir durante a flexão articular. Observou-se decréscimo significativo do perímetro muscular da coxa aos 30 e 90 dias p.o. em ambos os grupos. Não foram evidenciadas alterações nos graus de extensão e flexão articulares, na rotação interna da tíbia, na amplitude de movimento articular ou de doença articular degenerativa (DAD durante o período de avaliação em ambos os grupos. Conclui-se que a ITR, associada à técnica de estabilização articular, não produz alterações em nenhuma das variáveis estudadas em cães, quando comparada à estabilização intra-articular, isoladamente.Clinical and radiographic changes associated with intercondylar notchplasty (IN after transection of the cranial cruciate ligament (CCL followed by a fascial strip reconstruction were studied in nine adult dogs. The right stifle was submitted to IN followed by fascial strip reconstruction of the CCL (GI while in the left IN was not performed (GC. Dogs were evaluated the day prior to surgery, on the immediate postoperative day and at 30, 90 and 180 days after surgery, time at which a subgroup of three dogs were euthanatized. Instability and lameness significantly decreased throughout the evaluation period, although instability was

  5. Articular manifestations in patients with Lyme disease.

    Science.gov (United States)

    Vázquez-López, María Esther; Díez-Morrondo, Carolina; Sánchez-Andrade, Amalia; Pego-Reigosa, Robustiano; Díaz, Pablo; Castro-Gago, Manuel

    To determine the percentage of Lyme patients with articular manifestations in NW Spain and to know their evolution and response to treatment. A retrospective study (2006-2013) was performed using medical histories of confirmed cases of Lyme disease showing articular manifestations. Clinical and laboratory characteristics, together with the treatment and evolution of the patients, were analysed. Seventeen out of 108 LD confirmed patients (15.7%) showed articular manifestations. Regarding those 17 patients, 64.7%, 29.4% and 5.9% presented arthritis, arthralgia and bursitis, respectively. The knee was the most affected joint. Articular manifestations were often associated to neurological, dermatological and cardiac pathologies. Otherwise, most patients were in Stage III. The 11.8% of the cases progressed to a recurrent chronic arthritis despite the administration of an appropriate treatment. Lyme disease patients showing articular manifestations should be included in the diagnosis of articular affections in areas of high risk of hard tick bite, in order to establish a suitable and early treatment and to avoid sequels. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  6. Human stem cells and articular cartilage regeneration.

    Science.gov (United States)

    Inui, Atsuyuki; Iwakura, Takashi; Reddi, A Hari

    2012-11-05

    The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES) cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS) cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  7. Human Stem Cells and Articular Cartilage Regeneration

    Directory of Open Access Journals (Sweden)

    A. Hari Reddi

    2012-11-01

    Full Text Available  The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  8. Biochemical composition of the superficial layer of articular cartilage.

    Science.gov (United States)

    Crockett, R; Grubelnik, A; Roos, S; Dora, C; Born, W; Troxler, H

    2007-09-15

    To gain more information on the mechanism of lubrication in articular joints, the superficial layer of bovine articular cartilage was mechanically removed in a sheet of ice that formed on freezing the cartilage. Freeze-dried samples contained low concentrations of chondroitin sulphate and protein. Analysis of the protein by SDS PAGE showed that the composition of the sample was comparable to that of synovial fluid (SF). Attenuated total reflection infrared (ATR-IR) spectroscopy of the dried residue indicated that the sample contained mostly hyaluronan. Moreover, ATR-IR spectroscopy of the upper layer of the superficial layer, adsorbed onto silicon, showed the presence of phospholipids. A gel could be formed by mixing hyaluronan and phosphatidylcholine in water with mechanical properties similar to those of the superficial layer on cartilage. Much like the superficial layer of natural cartilage, the surface of this gel became hydrophobic on drying out. Thus, it is proposed that the superficial layer forms from hyaluronan and phospholipids, which associate by hydrophobic interactions between the alkyl chains of the phospholipids and the hydrophobic faces of the disaccharide units in hyaluronan. This layer is permeable to material from the SF and the cartilage, as shown by the presence of SF proteins and chondroitin sulphate. As the cartilage dries out after removal from the joint, the phospholipids migrate towards the surface of the superficial layer to reduce the surface tension. It is also proposed that the highly efficient lubrication in articular joints can, at least in part, be attributed to the ability of the superficial layer to adsorb and hold water on the cartilage surface, thus creating a highly viscous boundary protection.

  9. OPERATIVE MANAGEMENT OF INTRA-ARTICULAR DISTAL HUMERAL FRACTURES WITH LOCKING PLATES

    Directory of Open Access Journals (Sweden)

    Abhilekh

    2015-11-01

    Full Text Available BACKGROUND: Intra-articular distal humeral fractures are common, but complex elbow injuries. To obtain good results, anatomical reduction with rigid fixation and early range of mobilization is required. Treatment of these fractures with conventional plates is associated with many complications such as non-anatomic reduction of articular surfaces, malunion, non-union, loosening of implant, residual stiffness of the elbow and post-traumatic osteoarthrosis. In this situation the application of locking plates having a fixed angle plate screw construct can minimise most of the above complications. OBJECTIVE: To evaluate radiological and functional outcome of locking plate application for the management of intra-articular distal humeral fractures. MATERIAL AND METHODS: This prospective study was conducted from January 2013 to December 2014. We operated 20 patients of AO type-C intra-articular distal humeral fractures. Fracture was exposed using modified Campbell’s posterior approach in less comminuted fractures and a V-shaped Olecranon osteotomy was done to get better exposure of the articular surface in cases with severe articular comminution. The fracture was stabilized using an intercondylar screw, pre-contoured locking compression plates and/or locking reconstruction plates as per preoperative planning. Patients were reviewed at monthly interval for clinical-radiological evaluation. Final outcome measures included radiological assessment, range of motion and Mayo elbow performance score (MEPS. RESULTS: All the fractures were united at an average 12 weeks. Two patients developed numbness in the distribution of ulnar nerve and one patient developed superficial infection in immediate postoperative period. None of the patients had malunion and loosening of implant. The average arc of flexion-extension was 105`, although no patient had loss of supination/pronation. Mayo Elbow Performance Score was excellent in 15 (75%, good in 3 (15%, fair in 1 (5

  10. Cartilage regeneration and repair testing in a surrogate large animal model.

    Science.gov (United States)

    Simon, Timothy M; Aberman, Harold M

    2010-02-01

    The aging human population is experiencing increasing numbers of symptoms related to its degenerative articular cartilage (AC), which has stimulated the investigation of methods to regenerate or repair AC. However, the seemingly inherent limited capacity for AC to regenerate persists to confound the various repair treatment strategies proposed or studied. Animal models for testing AC implant devices and reparative materials are an important and required part of the Food and Drug Administration approval process. Although final testing is ultimately performed in humans, animal testing allows for a wider range of parameters and combinations of test materials subjected to all the biological interactions of a living system. We review here considerations, evaluations, and experiences with selection and use of animal models and describe two untreated lesion models useful for testing AC repair strategies. These created lesion models, one deep (6 mm and through the subchondral plate) the other shallow (to the level of the subchondral bone plate) were placed in the middle one-third of the medial femoral condyle of the knee joints of goats. At 1-year neither the deep nor the shallow full-thickness chondral defects generated a repair that duplicated natural AC. Moreover, progressive deleterious changes occurred in the AC surrounding the defects. There are challenges in translation from animals to humans as anatomy and structures are different and immobilization to protect delicate repairs can be difficult. The tissues potentially generated by proposed cartilage repair strategies must be compared with the spontaneous changes that occur in similarly created untreated lesions. The prevention of the secondary changes in the surrounding cartilage and subchondral bone described in this article should be addressed with the introduction of treatments for repairs of the articulating surface.

  11. Tendon repair

    Science.gov (United States)

    Repair of tendon ... Tendon repair can be performed using: Local anesthesia (the immediate area of the surgery is pain-free) ... a cut on the skin over the injured tendon. The damaged or torn ends of the tendon ...

  12. Mesenchymal stem cells as a potent cell source for articular cartilage regeneration

    Institute of Scientific and Technical Information of China (English)

    Mohamadreza; Baghaban; Eslaminejad; Elham; Malakooty; Poor

    2014-01-01

    Since articular cartilage possesses only a weak capac-ity for repair, its regeneration potential is considered one of the most important challenges for orthopedic surgeons. The treatment options, such as marrow stimulation techniques, fail to induce a repair tissue with the same functional and mechanical properties of native hyaline cartilage. Osteochondral transplantation is considered an effective treatment option but is as-sociated with some disadvantages, including donor-site morbidity, tissue supply limitation, unsuitable mechani-cal properties and thickness of the obtained tissue. Although autologous chondrocyte implantation results in reasonable repair, it requires a two-step surgical pro-cedure. Moreover, chondrocytes expanded in culture gradually undergo dedifferentiation, so lose morpho-logical features and specialized functions. In the search for alternative cells, scientists have found mesenchymal stem cells(MSCs) to be an appropriate cellular mate-rial for articular cartilage repair. These cells were origi-nally isolated from bone marrow samples and further investigations have revealed the presence of the cells in many other tissues. Furthermore, chondrogenic dif-ferentiation is an inherent property of MSCs noticedat the time of the cell discovery. MSCs are known to exhibit homing potential to the damaged site at which they differentiate into the tissue cells or secrete a wide spectrum of bioactive factors with regenerative proper-ties. Moreover, these cells possess a considerable im-munomodulatory potential that make them the general donor for therapeutic applications. All of these topics will be discussed in this review.

  13. Canine articular cartilage regeneration using mesenchymal stem cells seeded on platelet rich fibrin

    Science.gov (United States)

    Shams Asenjan, K.; Dehdilani, N.; Parsa, H.

    2017-01-01

    Objectives Mesenchymal stem cells have the ability to differentiate into various cell types, and thus have emerged as promising alternatives to chondrocytes in cell-based cartilage repair methods. The aim of this experimental study was to investigate the effect of bone marrow derived mesenchymal stem cells combined with platelet rich fibrin on osteochondral defect repair and articular cartilage regeneration in a canine model. Methods Osteochondral defects were created on the medial femoral condyles of 12 adult male mixed breed dogs. They were either treated with stem cells seeded on platelet rich fibrin or left empty. Macroscopic and histological evaluation of the repair tissue was conducted after four, 16 and 24 weeks using the International Cartilage Repair Society macroscopic and the O’Driscoll histological grading systems. Results were reported as mean and standard deviation (sd) and compared at different time points between the two groups using the Mann-Whitney U test, with a value regeneration. It is postulated that platelet rich fibrin creates a suitable environment for proliferation and differentiation of stem cells by releasing endogenous growth factors resulting in creation of a hyaline-like reparative tissue. Cite this article: D. Kazemi, K. Shams Asenjan, N. Dehdilani, H. Parsa. Canine articular cartilage regeneration using mesenchymal stem cells seeded on platelet rich fibrin: Macroscopic and histological assessments. Bone Joint Res 2017;6:98–107. DOI: 10.1302/2046-3758.62.BJR-2016-0188.R1. PMID:28235767

  14. Chondrogenic Differentiation of Human Adipose-Derived Stem Cells: A New Path in Articular Cartilage Defect Management?

    Directory of Open Access Journals (Sweden)

    Jan-Philipp Stromps

    2014-01-01

    Full Text Available According to data published by the Centers for Disease Control and Prevention, over 6 million people undergo a variety of medical procedures for the repair of articular cartilage defects in the U.S. each year. Trauma, tumor, and age-related degeneration can cause major defects in articular cartilage, which has a poor intrinsic capacity for healing. Therefore, there is substantial interest in the development of novel cartilage tissue engineering strategies to restore articular cartilage defects to a normal or prediseased state. Special attention has been paid to the expansion of chondrocytes, which produce and maintain the cartilaginous matrix in healthy cartilage. This review summarizes the current efforts to generate chondrocytes from adipose-derived stem cells (ASCs and provides an outlook on promising future strategies.

  15. Articular Cartilage Changes in Maturing Athletes

    Science.gov (United States)

    Luria, Ayala; Chu, Constance R.

    2014-01-01

    Context: Articular cartilage has a unique functional architecture capable of providing a lifetime of pain-free joint motion. This tissue, however, undergoes substantial age-related physiologic, mechanical, biochemical, and functional changes that reduce its ability to overcome the effects of mechanical stress and injury. Many factors affect joint function in the maturing athlete—from chondrocyte survival and metabolism to structural composition and genetic/epigenetic factors governing cartilage and synovium. An evaluation of age-related changes for joint homeostasis and risk for osteoarthritis is important to the development of new strategies to rejuvenate aging joints. Objective: This review summarizes the current literature on the biochemical, cellular, and physiologic changes occurring in aging articular cartilage. Data Sources: PubMed (1969-2013) and published books in sports health, cartilage biology, and aging. Study Selection: Keywords included aging, athlete, articular cartilage, epigenetics, and functional performance with age. Study Design: Systematic review. Level of Evidence: Level 3. Data Extraction: To be included, research questions addressed the effect of age-related changes on performance, articular cartilage biology, molecular mechanism, and morphology. Results: The mature athlete faces challenges in maintaining cartilage health and joint function due to age-related changes to articular cartilage biology, morphology, and physiology. These changes include chondrocyte loss and a decline in metabolic response, alterations to matrix and synovial tissue composition, and dysregulation of reparative responses. Conclusion: Although physical decline has been regarded as a normal part of aging, many individuals maintain overall fitness and enjoy targeted improvement to their athletic capacity throughout life. Healthy articular cartilage and joints are needed to maintain athletic performance and general activities. Genetic and potentially reversible

  16. Results of Latarjet Coracoid Transfer to Revise Failed Arthroscopic Instability Repairs

    Science.gov (United States)

    Nicholson, Gregory P.; Rahman, Zain; Verma, Nikhil N.; Romeo, Anthony A.; Cole, Brian J.; Gupta, Anil Kumar; Bruce, Benjamin

    2014-01-01

    Objectives: Arthroscopic instability repair has supplanted open techniques to anatomically reconstruct anteroinferior instability pathology. Arthroscopic technique can fail for a variety of reasons. We have utilized the Latarjet as a revision option in failed arthroscopic instability repairs when there is altered surgical anatomy, capsular deficiency and/or glenoid bone compromise and recurrent glenohumeral instability. Methods: We reviewed 51 shoulders (40 ♀, 11♂) that underwent Latarjet coracoid transfer for the revision of failed previous arthroscopic instability repair. The avg. age was 32.6 yrs (16-58). All patients had recurrent symptomatic anterior instability after previous arthroscopic surgery, and avg. time from arthroscopic repair to Latarjet was 13 months (4-40 mn). All had either CT or MRI that revealed suture anchor material in the glenoid, labral and capsular stripping, and anteroinferior glenoid bone loss or erosion. Advanced bone loss percentage analysis was not performed for this study. We excluded all patients that had a previous open repair, a seizure disorder, or if the Latarjet was a primary procedure. Outcome scores pre-operatively avg: SST: 6.7 (1-12); VAS: 3 (0-8); ASES: 63 (32-89). Coracoid transfer was performed thru a subscapularis split in 38, and with tendon takedown in 13. The coracoid was osteotomized along its long axis parallel to the undersurface of the lateral aspect. This provided at least 2.5 to 3.5 cm of graft with the conjoined tendon attached. The coracoacromial (CA) ligament was incised leaving a 1 cm. stump. The transfer was affixed flush with the articular surface but not lateral to it, with two 3.5 mm cortical screws in lag fashion overdrilling the coracoid with the CA ligament directed laterally. The capsule was then repaired to the CA ligament to make the transfer extra-articular. Results: At avg. 4 yr (2-7 yrs) follow-up stability had been maintained in 51 (100%).without further instability surgery. There were no

  17. Articular chondrocyte metabolism and osteoarthritis

    Energy Technology Data Exchange (ETDEWEB)

    Leipold, H.R.

    1989-01-01

    The three main objectives of this study were: (1) to determine if depletion of proteoglycans from the cartilage matrix that occurs during osteoarthritis causes a measurable increase of cartilage proteoglycan components in the synovial fluid and sera, (2) to observe what effect intracellular cAMP has on the expression of matrix components by chondrocytes, and (3) to determine if freshly isolated chondrocytes contain detectable levels of mRNA for fibronectin. Canine serum keratan sulfate and hyaluronate were measured to determine if there was an elevation of these serum glycosaminoglycans in a canine model of osteoarthritis. A single intra-articular injection of chymopapain into a shoulder joint increased serum keratan sulfate 10 fold and hyaluronate less than 2 fold in 24 hours. Keratan sulfate concentrations in synovial fluids of dogs about one year old were unrelated to the presence of spontaneous cartilage degeneration in the joints. High keratan sulfate in synovial fluids correlated with higher keratan sulfate in serum. The mean keratan sulfate concentration in sera of older dogs with osteoarthritis was 37% higher than disease-free controls, but the difference between the groups was not statistically significant. Treatment of chondrocytes with 0.5 millimolar (mM) dibutyryl cAMP (DBcAMP) caused the cells to adopt a more rounded morphology. There was no difference between the amount of proteins synthesized by cultures treated with DBcAMP and controls. The amount of fibronectin (FN) in the media of DBcAMP treated cultures detected by an ELISA was specifically reduced, and the amount of {sup 35}S-FN purified by gelatin affinity chromatography decreased. Moreover, the percentage of FN containing the extra domain. A sequence was reduced. Concomitant with the decrease in FN there was an increase in the concentration of keratan sulfate.

  18. Inverse Kinematics and Model Calibration Optimization of a Five-D.O.F. Robot for Repairing the Surface Profiles of Hydraulic Turbine Blades

    Directory of Open Access Journals (Sweden)

    Jose Mauricio S.T. Motta

    2016-06-01

    Full Text Available This paper presents and discusses the results of an ongoing R&D project aiming to design and build a fully automated prototype of a specialized spherical robotic welding system for repairing hydraulic turbine surfaces eroded by cavitation pitting and/or cracks produced by cyclic loading. The system has an embedded vision sensor built to acquire range images by laser scanning over the blade’s surface and produce 3D models to locate the damaged spots to be registered in a 3D coordinate system into the robot controller, enabling the robot to repair the flaws automatically by welding in layers. The paper is focused on the robot kinematic model and describes an iterative algorithm to process the inverse kinematics with only five degrees-of-freedom. The algorithm makes use of data collected from a vision sensor to ensure that the welding gun axis is perpendicular to the blade’s surface. Besides this, it proposes a modelling and optimization mathematical routine for more efficient robot calibration, which can be used with any type of robot. This robot calibration optimization scheme finds the optimal error parameter vector based on the condition number of the manipulator transformation composed from the partial derivatives of the error parameters. Experimental results proved both the iterative algorithm to perform the inverse kinematics and the technique to optimize robot calibration to be very efficient.

  19. System and method for laser-based, non-evaporative repair of damage sites in the surfaces of fused silica optics

    Energy Technology Data Exchange (ETDEWEB)

    Adams, John J.; Bolourchi, Masoud; Bude, Jeffrey D.; Guss, Gabriel M.; Jarboe, Jeffery A.; Matthews, Manyalibo J.; Nostrand, Michael C; Wegner, Paul J.

    2016-09-06

    A method for repairing a damage site on a surface of an optical material is disclosed. The method may involve focusing an Infrared (IR) laser beam having a predetermined wavelength, with a predetermined beam power, to a predetermined full width ("F/W") 1/e.sup.2 diameter spot on the damage site. The focused IR laser beam is maintained on the damage site for a predetermined exposure period corresponding to a predetermined acceptable level of downstream intensification. The focused IR laser beam heats the damage site to a predetermined peak temperature, which melts and reflows material at the damage site of the optical material to create a mitigated site.

  20. Equine articular synovial cysts: 16 cases.

    Science.gov (United States)

    Lacourt, Mathieu; MacDonald, Melinda; Rossier, Yves; Laverty, Sheila

    2013-01-01

    To report the clinical findings, diagnosis, treatment and outcome of equine patients with articular synovial cysts. Retrospective case series. Horses (n = 16) with articular synovial cysts. Horses diagnosed with articular synovial cysts (1988-2009) at 2 veterinary teaching hospitals were studied. Signalment, history, clinical signs, diagnostic methods and treatment were retrieved and telephone follow-up was obtained. Sixteen horses with articular synovial cysts were identified. Lameness was the reason for referral in most (n = 9) horses. Diagnosis was based on a combination of palpation and imaging studies, including radiography, ultrasonography and/or arthrography. Excision of the cyst was performed in 8 horses. Outcome was available for 4 surgically and 2 conservatively treated horses. Lameness resolved in 3 horses treated surgically and the 4th died for unrelated reasons. The 2 conservatively treated horses performed satisfactorily for the rest of their career. Equine articular synovial cysts are rare and can be associated with lameness. The cysts had a synovial lining in all horses where it was assessed. Surgical excision may be successful in resolving the lameness and allowing selected horses to return to work. © Copyright 2012 by The American College of Veterinary Surgeons.

  1. Imaging of the cervical articular pillar

    Energy Technology Data Exchange (ETDEWEB)

    Yeomans, E. [Orange Base Hospital, Orange, NSW (Australia)

    1998-12-01

    The cervical articular pillar, due to the complex anatomical structure of the cervical spine, is not well demonstrated in routine plain radiographic views. Dedicated views have been devised to demonstrate the pillar, yet their performance has abated considerably since the inception of Computed Tomography (CT) in the 1970`s. It is the consideration that CT does not image the articular pillar with a 10 per cent accuracy that poses the question: Is there still a need for plain radiography of the cervical articular pillar? This paper studies the anatomy, plain radiography, and incidence of injury to the cervical articular pillar. It discusses (with reference to current and historic literature) the efficacy of current imaging protocols in depicting this injury. It deals with plain radiography, CT, complex tomography, and Magnetic Resonance Imaging (MRI) of the cervical spine to conclude there may still be a position in current imaging protocols for plain radiography of the cervical articular pillar. Copyright (1998) Australian Institute of Radiography 43 refs., 5 figs.

  2. Progression of Gene Expression Changes following a Mechanical Injury to Articular Cartilage as a Model of Early Stage Osteoarthritis.

    Science.gov (United States)

    McCulloch, R S; Ashwell, M S; Maltecca, C; O'Nan, A T; Mente, P L

    2014-01-01

    An impact injury model of early stage osteoarthritis (OA) progression was developed using a mechanical insult to an articular cartilage surface to evaluate differential gene expression changes over time and treatment. Porcine patellae with intact cartilage surfaces were randomized to one of three treatments: nonimpacted control, axial impaction (2000 N), or a shear impaction (500 N axial, with tangential displacement to induce shear forces). After impact, the patellae were returned to culture for 0, 3, 7, or 14 days. At the appropriate time point, RNA was extracted from full-thickness cartilage slices at the impact site. Quantitative real-time PCR was used to evaluate differential gene expression for 18 OA related genes from four categories: cartilage matrix, degradative enzymes and inhibitors, inflammatory response and signaling, and cell apoptosis. The shear impacted specimens were compared to the axial impacted specimens and showed that shear specimens more highly expressed type I collagen (Col1a1) at the early time points. In addition, there was generally elevated expression of degradative enzymes, inflammatory response genes, and apoptosis markers at the early time points. These changes suggest that the more physiologically relevant shear loading may initially be more damaging to the cartilage and induces more repair efforts after loading.

  3. Bladder exstrophy repair

    Science.gov (United States)

    Bladder birth defect repair; Everted bladder repair; Exposed bladder repair; Repair of bladder exstrophy ... Bladder exstrophy repair involves two surgeries. The first surgery is to repair the bladder and the second one is to attach ...

  4. Development of artificial articular cartilage

    Indian Academy of Sciences (India)

    Biswajit Bera

    2009-10-01

    The present study describes the development of artificial articular cartilage on the basis of mimicking structural gel properties and mechanical gel properties of natural articular cartilage. It is synthesized from PVA/Si nanocomposite containing 20% Tetra ethoxy silane (TEOS) by sol–gel method. Mechanical strength of Poly(vinyl alcohol), PVA is improved up to 35 MPa. Manufacturing method is adopted considering colloidal stability of nano silica particle in PVA sol at specific pH = 1. An adhesive is also prepared from PVA/Si nanocomposite containing 40% TEOS for firm attachment of artificial articular cartilage on underlying bone with high bond strength.

  5. Label-free characterization of articular cartilage in osteoarthritis model mice by Raman spectroscopy

    Science.gov (United States)

    Oshima, Yusuke; Akehi, Mayu; Kiyomatsu, Hiroshi; Miura, Hiromasa

    2017-02-01

    Osteoarthritis (OA) is very common joint disease in the aging population. Main symptom of OA is accompanied by degenerative changes of articular cartilage. Cartilage contains mostly type II collagen and proteoglycans, so it is difficult to access the quality and morphology of cartilage tissue in situ by conventional diagnostic tools (X-ray, MRI and echography) directly or indirectly. Raman spectroscopy is a label-free technique which enables to analyze molecular composition in degenerative cartilage. In this study, we generated an animal OA model surgically induced by knee joint instability, and the femurs were harvested at two weeks after the surgery. We performed Raman spectroscopic analysis for the articular cartilage of distal femurs in OA side and unaffected side in each mouse. In the result, there is no gross findings in the surface of the articular cartilage in OA. On the other hand, Raman spectral data of the articular cartilage showed drastic changes in comparison between OA and control side. The major finding of this study is that the relative intensity of phosphate band (960 cm-1) increases in the degenerative cartilage. This may be the result of exposure of subchondral bone due to thinning of the cartilage layer. In conclusion, Raman spectroscopic technique is sufficient to characterize articular cartilage in OA as a pilot study for Raman application in cartilage degeneration and regeneration using animal models and human subjects.

  6. Intra-articular angiolipoma of the knee: a case report

    Directory of Open Access Journals (Sweden)

    Nishimori Makoto

    2010-04-01

    Full Text Available Abstract We report a case of intra-articular angiolipoma of the knee. This case report describes our experience in excising an intra-articular angiolipoma of the knee joint. Complete resection under arthroscopy was performed in a 30-year-old man. Two years after the surgery, no evidence of recurrence was seen. Intra-articular angiolipomas should be considered in the differential diagnosis of intra-articular masses in adolescents with recurrent hemarthrosis without trauma.

  7. INCREASING EFFICIENCY OF REPAIRING, MANUFACTURING AND OPERATION OF THE TPP FACILITIES BY TECHNOLOGY OF GAS-THERMAL COATING AND LASER SURFACE MELTING

    Directory of Open Access Journals (Sweden)

    O. E. Grachev

    2015-01-01

    Full Text Available The article considers effectiveness increase of the TPP heat-mechanical equipment repair, manufacturing and maintenance as exemplified by gas-thermal technique for hardening laststages rotor blades of the steam turbines. The rotor blades work under conditions of intense power loading, their airfoil being erosion-corrosion destructed by the action of the moist-steam flow. Repairing companies employ quite a number of technologies to restore some of erosion-worn rotor blades. Inter alia, argon-arc, plasma and gas-powder weld deposition of the original material with subsequent machining, stellite protection recovery, electrical spark alloying the entry edge mat surface, spraying ion-plasma coating on the blade airfoil surface. In domestic turbine building, rotor blades of the steam turbines last stages are manufactured of martensitic class stainless steel. The key condition for successful blade restoration is thermal effect minimizing on the base material for excluding the slag areas possible forming. The laser surface coating technology provides these conditions. They coat the surface of an item being processed by way of melting the base and the adding material. In as much the base melts smallest, the coating characteristics depend mainly on the properties of adding material. The procedure of laser coating passes through several stages including physical contact creation, chemical interaction (laser radiation absorption, volumetrical processes resulting in formation of stable bonds in volume of the materials that have reacted. For the low-pressure cylinder rotor blades supplementary protection against erosion destruction, LLC ‘Technological Systems of Protective Coating’ developed technology of the blade airfoil protective finish by method of high-speed gas-flame sputter. The company realized this technology in 2012 during K-200-12,8 turbine (of the Leningrad Metallurgical Works – LMZ repairing in Zainsk SDPP by JSC ‘Tatenergo’. The

  8. Preparation of Articular Cartilage Specimens for Scanning Electron Microscopy.

    Science.gov (United States)

    Stupina, T A

    2016-08-01

    We developed and adapted a technology for preparation of articular cartilage specimens for scanning electron microscopy. The method includes prefixation processing, fixation, washing, and dehydration of articular cartilage specimens with subsequent treatment in camphene and air-drying. The technological result consists in prevention of deformation of the articular cartilage structures. The method is simpler and cheaper than the known technologies.

  9. A comparison of healthy human and swine articular cartilage dynamic indentation mechanics.

    Science.gov (United States)

    Ronken, S; Arnold, M P; Ardura García, H; Jeger, A; Daniels, A U; Wirz, D

    2012-05-01

    Articular cartilage is a multicomponent, poroviscoelastic tissue with nonlinear mechanical properties vital to its function. A consequent goal of repair or replacement of injured cartilage is to achieve mechanical properties in the repair tissue similar to healthy native cartilage. Since fresh healthy human articular cartilage (HC) is not readily available, we tested whether swine cartilage (SC) could serve as a suitable substitute for mechanical comparisons. To a first approximation, cartilage tissue and surgical substitutes can be evaluated mechanically as viscoelastic materials. Stiffness measurements (dynamic modulus, loss angle) are vital to function and are also a non-destructive means of evaluation. Since viscoelastic material stiffness is strongly strain rate dependent, stiffness was tested under different loading conditions related to function. Stiffness of healthy HC and SC specimens was determined and compared using two non-destructive, mm-scale indentation test modes: fast impact and slow sinusoidal deformation. Deformation resistance (dynamic modulus) and energy handling (loss angle) were determined. For equivalent anatomic locations, there was no difference in dynamic modulus. However, the HC loss angle was ~35% lower in fast impact and ~12% higher in slow sinusoidal mode. Differences seem attributable to age (young SC, older HC) but also to species anatomy and biology. Test mode-related differences in human-swine loss angle support use of multiple function-related test modes. Keeping loss angle differences in mind, swine specimens could serve as a standard of comparison for mechanical evaluation of e.g. engineered cartilage or synthetic repair materials.

  10. Salvage hypospadias repairs

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    Sripathi V

    2008-01-01

    Full Text Available Aim: Review of our experience and to develop an algorithm for salvage procedures in the management of hypospadias cripples and treatment of urethral strictures following hypospadias repair. Methods: This is a retrospective review of hypospadias surgeries over a 41-month period. Out of a total 168 surgeries, 20 were salvage/re-operative repairs. In three children a Duplay repair was feasible, while in four others a variety of single-stage repairs could be done. The repair was staged in seven children - buccal mucosal grafts (BMGs in five, buccal mucosal tube in one, and skin graft in one. Five children with dense strictures were managed by dorsal BMG inlay grafting in one, vascularized tunical onlay grafting on the ventrum in one, and a free tunical patch in one. Three children were treated by internal urethrotomy and stenting for four weeks with a poor outcome. Results: The age of children ranged from 1.5-15 years (mean 4.5. Follow-up ranged from 3 months to 3.5 years. Excellent results were obtained in 10 children (50% with a well-surfaced erect penis and a slit-like meatus. Glans closure could not be achieved and meatus was coronal in three. Two children developed fistulae following a Duplay repair and following a staged BMG. Three repairs failed completely - a composite repair broke down, a BMG tube stenosed with a proximal leak, and a stricture recurred with loss of a ventral free tunical graft. Conclusions: In salvage procedures performed on hypospadias cripples, a staged repair with buccal mucosa as an inlay in the first stage followed by tubularization 4-6 months later provides good results. A simple algorithm to plan corrective surgery in failed hypospadias cases and obtain satisfactory results is devised.

  11. Comparative Study of the Use of Intra-articular and Systemic Meloxicam to Control Experimentally Induced Osteoarthritis in Rabbit Knees

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    Valeria Trombini Vidotto

    2013-12-01

    Full Text Available Objective: This study aimed to evaluate morphologic changes, as well as chondroprotective and intra-articular effects of meloxicam on joint repair in rabbits induced by experimental trochleoplasty, minimizing possible adverse side effects. Methods: Thirty-five rabbits were divided into four groups: the control group, which did not undergo surgery, and operated groups, which used different ways of administering the anti-inflammatory agent: systemic, 0.2 mg/kg; intra-articular, 0.5 mg/kg; positive group control, without meloxicam. Each operated group was divided according to the periods of 7 or 30 days evaluation after surgery. Results: Regarding macroscopic and histological evaluation of cartilage, after 30 days, most animals showed almost complete joint repair, the presence of few or no inflammatory cells; whereas part of the animals treated with meloxicam presented necrosis in the trochlear ridge and absence of inflammatory cells after 7 days. In positive control group, it was observed moderate inflammation and connective tissue proliferation. None of the animals in the operated groups showed irregularities 30 days after surgery. Conclusion: Either intra-articular or systemic, meloxicam revealed to be favorable to be used for joint repair and control of inflammatory reaction.

  12. Does joint architecture influence the nature of intra-articular fractures?

    Science.gov (United States)

    Steer, R A; Smith, S D; Lang, A; Hohmann, E; Tetsworth, K D

    2015-07-01

    The architecture of joints has potentially the greatest influence on the nature of intra-articular fractures. We analysed a large number of intra-articular fractures with two aims: (1) to determine if the pattern of injuries observed supports our conjecture that the local skeletal architecture is an important factor and (2) to investigate whether associated dislocations further affect the fracture pattern. A retrospective study of intra-articular fractures over a 3.5-year period; 1003 joints met inclusion criteria and were analysed. Three independent investigators determined if fractures affected the convex dome, the concave socket, or if both joint surfaces were involved. Further review determined if a joint dislocation occurred with the initial injury. Statistical analysis was performed using a one-way frequency table, and the χ(2) test was used to compare the frequencies of concave and convex surface fractures. The odds ratios (ORs) were calculated to establish the association between the frequencies of concave and convex surface fractures, as well as between dislocation and either fracture surface involvement. Of the 1003 fractures analysed, 956 (95.3%) involved only the concavity of the joint; in 21 fractures (2.1%) both joint surfaces were involved; and in 26 fractures (2.6%) only the convexity was involved (χ(2)=1654.9, df=2, parchitecture of joints clearly plays a highly significant role in determining the nature of intra-articular fractures. Intra-articular fractures involving the convexity are much more likely to be associated with a concurrent joint dislocation. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  13. Increasing lateral tibial slope: is there an association with articular cartilage changes in the knee?

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Nasir; Shepel, Michael; Leswick, David A.; Obaid, Haron [University of Saskatchewan, Department of Medical Imaging, Royal University Hospital, and College of Medicine, Saskatoon, Saskatchewan (Canada)

    2014-04-15

    The geometry of the lateral tibial slope (LTS) plays an important role in the overall biomechanics of the knee. Through this study, we aim to assess the impact of LTS on cartilage degeneration in the knee. A retrospective analysis of 93 knee MRI scans (1.5 T or 3 T) for patients aged 20-45 years with no history of trauma or knee surgery, and absence of internal derangement. The LTS was calculated using the circle method. Chondropathy was graded from 0 (normal) to 3 (severe). Linear regression analysis was used for statistical analysis (p < 0.05). In our cohort of patients, a statistically significant association was seen between increasing LTS and worsening cartilage degenerative changes in the medial patellar articular surface and the lateral tibial articular surface (p < 0.05). There was no statistically significant association between increasing LTS and worsening chondropathy of the lateral patellar, medial trochlea, lateral trochlea, medial femoral, lateral femoral, and medial tibial articular surfaces. Our results show a statistically significant association between increasing LTS and worsening cartilage degenerative changes in the medial patella and the lateral tibial plateau. We speculate that increased LTS may result in increased femoral glide over the lateral tibial plateau with subsequent increased external rotation of the femur predisposing to patellofemoral articular changes. Future arthroscopic studies are needed to further confirm our findings. (orig.)

  14. Serial variation in histological character of articular soft tissue in young human adult temporomandibular joint condyles.

    Science.gov (United States)

    Bibb, C A; Pullinger, A G; Baldioceda, F

    1993-04-01

    Histological variation was studied in serial sections, in contrast to previous studies which have generalized from representative sections. The sample consisted of consecutive serial sagittal sections from the central third of nine condyles, plus an accompanying stone cast showing the intact articular surface before sectioning. The thickness of the articular soft tissue and its fibrous connective tissue and cartilage components was measured, and the presence of undifferentiated mesenchymal (UM) cells was assessed by low-power light microscopy. Components of variance analysis showed that section-to-section variation in thickness was of the same order as differences between joints, each explaining approx. 50% of the variance in both connective tissue and cartilage thickness. The fibrous connective tissue contributed as much to the overall variation in soft tissue thickness as did the cartilage component (SD 0.0946 versus 0.0909 mm for the superior sector). Serial UM cell variability was common, and the UM cells were often distributed in islands rather than uniformly across the articular tissue. Condyles with the greatest surface irregularity were characterized by greater serial variability in fibrous connective tissue thickness, more frequent absence of cartilage, and more areas of UM cell depletion. These results suggest that serial variation in histological character may be more important than mean values in the description of surface contours and articular tissue relations in the temporomandibular joint. This should influence the design of future investigations.

  15. Experience of high-nitrogenous steel powder application in repairs and surface hardening of responsible parts for power equipment by plasma spraying

    Science.gov (United States)

    Kolpakov, A. S.; Kardonina, N. I.

    2016-02-01

    The questions of the application of novel diffusion-alloying high-nitrogenous steel powders for repair and surface hardening of responsible parts of power equipment by plasma spraying are considered. The appropriateness of the method for operative repair of equipment and increasing its service life is justified. General data on the structure, properties, and manufacture of nitrogen-, aluminum-, and chromium-containing steel powders that are economically alloyed using diffusion are described. It is noted that the nitrogen release during the decomposition of iron nitrides, when heating, protects the powder particles from oxidation in the plasma jet. It is shown that the coating retains 50% of nitrogen that is contained in the powder. Plasma spraying modes for diffusion-alloying high-nitrogenous steel powders are given. The service properties of plasma coatings based on these powders are analyzed. It is shown that the high-nitrogenous steel powders to a nitrogen content of 8.9 wt % provide the necessary wear resistance and hardness of the coating and the strength of its adhesion to the substrate and corrosion resistance to typical aggressive media. It is noted that increasing the coating porosity promotes stress relaxation and increases its thickness being limited with respect to delamination conditions in comparison with dense coatings on retention of the low defectiveness of the interface and high adhesion to the substrate. The examples of the application of high-nitrogenous steel powders in power engineering during equipment repairs by service companies and overhaul subdivisions of heat power plants are given. It is noted that the plasma spraying of diffusion-alloyed high-nitrogenous steel powders is a unique opportunity to restore nitrided steel products.

  16. Body weight independently affects articular cartilage catabolism.

    Science.gov (United States)

    Denning, W Matt; Winward, Jason G; Pardo, Michael Becker; Hopkins, J Ty; Seeley, Matthew K

    2015-06-01

    Although obesity is associated with osteoarthritis, it is unclear whether body weight (BW) independently affects articular cartilage catabolism (i.e., independent from physiological factors that also accompany obesity). The primary purpose of this study was to evaluate the independent effect of BW on articular cartilage catabolism associated with walking. A secondary purpose was to determine how decreased BW influenced cardiovascular response due to walking. Twelve able-bodied subjects walked for 30 minutes on a lower-body positive pressure treadmill during three sessions: control (unadjusted BW), +40%BW, and -40%BW. Serum cartilage oligomeric matrix protein (COMP) was measured immediately before (baseline) and after, and 15 and 30 minutes after the walk. Heart rate (HR) and rate of perceived exertion (RPE) were measured every three minutes during the walk. Relative to baseline, average serum COMP concentration was 13% and 5% greater immediately after and 15 minutes after the walk. Immediately after the walk, serum COMP concentration was 14% greater for the +40%BW session than for the -40%BW session. HR and RPE were greater for the +40%BW session than for the other two sessions, but did not differ between the control and -40%BW sessions. BW independently influences acute articular cartilage catabolism and cardiovascular response due to walking: as BW increases, so does acute articular cartilage catabolism and cardiovascular response. These results indicate that lower-body positive pressure walking may benefit certain individuals by reducing acute articular cartilage catabolism, due to walking, while maintaining cardiovascular response. Key pointsWalking for 30 minutes with adjustments in body weight (normal body weight, +40% and -40% body weight) significantly influences articular cartilage catabolism, measured via serum COMP concentration.Compared to baseline levels, walking with +40% body weight and normal body weight both elicited significant increases in

  17. Magnetic Resonance Imaging of Cartilage Repair

    Science.gov (United States)

    Trattnig, Siegfried; Winalski, Carl S.; Marlovits, Stephan; Jurvelin, Jukka S.; Welsch, Goetz H.; Potter, Hollis G.

    2011-01-01

    Articular cartilage lesions are a common pathology of the knee joint, and many patients may benefit from cartilage repair surgeries that offer the chance to avoid the development of osteoarthritis or delay its progression. Cartilage repair surgery, no matter the technique, requires a noninvasive, standardized, and high-quality longitudinal method to assess the structure of the repair tissue. This goal is best fulfilled by magnetic resonance imaging (MRI). The present article provides an overview of the current state of the art of MRI of cartilage repair. In the first 2 sections, preclinical and clinical MRI of cartilage repair tissue are described with a focus on morphological depiction of cartilage and the use of functional (biochemical) MR methodologies for the visualization of the ultrastructure of cartilage repair. In the third section, a short overview is provided on the regulatory issues of the United States Food and Drug Administration (FDA) and the European Medicines Agency (EMEA) regarding MR follow-up studies of patients after cartilage repair surgeries. PMID:26069565

  18. Effect of gradual weight-bearing on regenerated articular cartilage after joint distraction and motion in a rabbit model.

    Science.gov (United States)

    Nishino, Tomofumi; Ishii, Tomoo; Chang, Fei; Yanai, Takaji; Watanabe, Arata; Ogawa, Takeshi; Mishima, Hajime; Nakai, Kenjiro; Ochiai, Naoyuki

    2010-05-01

    The purpose of this study was to clarify the effect of gradual weight bearing (GWB) on regenerating cartilage. We developed a novel external fixation device (EFD) with a controllable weight-bearing system and continuous passive motion (CPM). A full-thickness defect was created by resection of the entire articular surface of the tibial plateau after the EFD was fixed in the rabbit's left knee. In the GWB group (n=6), GWB was started 6 weeks after surgery. In the CPM group (n=6), CPM with EFD was applied in the same manner without GWB. The control group (n=5) received only joint distraction. All rabbits were sacrificed 9 weeks after surgery. The central one-third of the regenerated tissue was assessed and scored blindly using a grading scale modified from the International Cartilage Repair Society visual histological assessment scale. The areas stained by Safranin-O and type II collagen antibody were measured, and the percentage of each area was calculated. There was no significant difference in the histological assessment scale among the groups. The percentage of the type II collagen-positive area was significantly larger in the GWB group than in the CPM group. The present study suggests that optimal mechanical stress, such as GWB, may affect regeneration of cartilage, in vivo.

  19. An investigation of abrasive wear and corrosion behavior of surface repair of gray cast iron by SMAW

    Directory of Open Access Journals (Sweden)

    Alireza Sadeghi

    2017-01-01

    Full Text Available In this work, improving the abrasion–corrosion behavior of gray cast iron used in centrifugal pumps was studied. These pumps are usually made of gray cast iron (BS:1452Gr220 and are repaired by Shielded Metal Arc Welding (SMAW. Three different typical welding electrodes including Ni electrode (DIN8563, Carbon Steel electrode (DIN1913, and Hardening electrode (DIN8555 were used to compare the weldability of the base metal. Microstructural differences for three types of electrodes were studied and forming of different phases was analyzed. Corrosion and abrasion tests were conducted and related to welding conditions. Experimental results showed that using Ni substrate electrode reduce the unwanted phases (martensitic and carbides. Furthermore, in comparison with the base metal, the abrasion behavior of all weldments was improved. It was also determined that the carbon steel electrode has a higher corrosion resistance in zero-resistance ammeter (ZRA test compared to other electrodes.

  20. BMP receptor signaling is required for postnatal maintenance of articular cartilage.

    Directory of Open Access Journals (Sweden)

    Ryan B Rountree

    2004-11-01

    Full Text Available Articular cartilage plays an essential role in health and mobility, but is frequently damaged or lost in millions of people that develop arthritis. The molecular mechanisms that create and maintain this thin layer of cartilage that covers the surface of bones in joint regions are poorly understood, in part because tools to manipulate gene expression specifically in this tissue have not been available. Here we use regulatory information from the mouse Gdf5 gene (a bone morphogenetic protein [BMP] family member to develop new mouse lines that can be used to either activate or inactivate genes specifically in developing joints. Expression of Cre recombinase from Gdf5 bacterial artificial chromosome clones leads to specific activation or inactivation of floxed target genes in developing joints, including early joint interzones, adult articular cartilage, and the joint capsule. We have used this system to test the role of BMP receptor signaling in joint development. Mice with null mutations in Bmpr1a are known to die early in embryogenesis with multiple defects. However, combining a floxed Bmpr1a allele with the Gdf5-Cre driver bypasses this embryonic lethality, and leads to birth and postnatal development of mice missing the Bmpr1a gene in articular regions. Most joints in the body form normally in the absence of Bmpr1a receptor function. However, articular cartilage within the joints gradually wears away in receptor-deficient mice after birth in a process resembling human osteoarthritis. Gdf5-Cre mice provide a general system that can be used to test the role of genes in articular regions. BMP receptor signaling is required not only for early development and creation of multiple tissues, but also for ongoing maintenance of articular cartilage after birth. Genetic variation in the strength of BMP receptor signaling may be an important risk factor in human osteoarthritis, and treatments that mimic or augment BMP receptor signaling should be

  1. Correlation between radiographic findings of osteoarthritis and arthroscopic findings of articular cartilage degeneration within the patellofemoral joint

    Energy Technology Data Exchange (ETDEWEB)

    Kijowski, Richard; Blankenbaker, Donna; Stanton, Paul; De Smet, Arthur [University of Wisconsin Hospital Clinical Science Center-E3/311, Department of Radiology, Madison, WI (United States); Fine, Jason [University of Wisconsin Clinical Science Center-K6/4675, Department of Statistics, Madison, WI (United States)

    2006-12-15

    To correlate radiographic findings of osteoarthritis on axial knee radiographs with arthroscopic findings of articular cartilage degeneration within the patellofemoral joint in patients with chronic knee pain. The study group consisted of 104 patients with osteoarthritis of the patellofemoral joint and 30 patients of similar age with no osteoarthritis of the patellofemoral joint. All patients in the study group had an axial radiograph of the knee performed prior to arthroscopic knee surgery. At the time of arthroscopy, each articular surface of the patellofemoral joint was graded using the Noyes classification system. Two radiologists retrospectively reviewed the knee radiographs to determine the presence of marginal osteophytes, joint-space narrowing, subchondral sclerosis, and subchondral cysts. The sensitivity and specificity of the various radiographic features of osteoarthritis for the detection of articular cartilage degeneration within the patellofemoral joint were determined. The sensitivity of marginal osteophytes, joint-space narrowing, subchondral sclerosis, and subchondral cysts for the detection of articular cartilage degeneration within the patellofemoral joint was 73%, 37%, 4%, and 0% respectively. The specificity of marginal osteophytes, joint-space narrowing, subchondral sclerosis, and subchondral cysts for the detection of articular cartilage degeneration within the patellofemoral joint was 67%, 90%, 100%, and 100% respectively. Marginal osteophytes were the most sensitive radiographic feature for the detection of articular cartilage degeneration within the patellofemoral joint. Joint-space narrowing, subchondral sclerosis, and subchondral cysts were insensitive radiographic features of osteoarthritis, and rarely occurred in the absence of associated osteophyte formation. (orig.)

  2. Effect of low-level helium-neon laser therapy on histological and ultrastructural features of immobilized rabbit articular cartilage.

    Science.gov (United States)

    Bayat, Mohammad; Ansari, Enayatallah; Gholami, Narges; Bayat, Aghdas

    2007-05-25

    The present study investigates whether low-level helium-neon laser therapy can increase histological parameters of immobilized articular cartilage in rabbits or not. Twenty five rabbits were divided into three groups: the experiment group, which received low-level helium-neon laser therapy with 13J/cm(2) three times a week after immobilization of their right knees; the control group which did not receive laser therapy after immobilization of their knees; and the normal group which received neither immobilization nor laser therapy. Histological and electron microscopic examinations were performed at 4 and 7 weeks after immobilization. Depth of the chondrocyte filopodia in four-week immobilized experiment group, and depth of articular cartilage in seven-week immobilized experiment group were significantly higher than those of relevant control groups (exact Fisher test, p=0.001; student's t-test, p=0.031, respectively). The surfaces of articular cartilages of the experiment group were relatively smooth, while those of the control group were unsmooth. It is therefore concluded that low-level helium-neon laser therapy had significantly increased the depth of the chondrocyte filopodia in four-week immobilized femoral articular cartilage and the depth of articular cartilage in seven-week immobilized knee in comparison with control immobilized articular cartilage.

  3. Geometry of the articular facets of the lateral atlanto-axial joints in the case of occipitalization.

    Science.gov (United States)

    Ryniewicz, A M; Skrzat, J; Ryniewicz, A; Ryniewicz, W; Walocha, J

    2010-08-01

    This study investigates if atlanto-occipital fusion affects the size and geometrical configuration of the articular facets of the atlanto-axial joint. Morphometric analysis was performed on the male adult skull, the occipital bone of which is assimilated with the first cervical vertebrae (the atlas). The perimeter, Feret's diameter, surface area, and circularity of the inferior articular fa-cets were measured. However, we did not observe significant bilateral differences in size of the inferior articular facets of the assimilated atlas compared to normal first cervical vertebrae. Geometrical conformation of the articular facets of the atlas and axis was assessed using a coordinate measuring machine (PMM - 12106, Leitz). The results obtained from this machine indicated that the inferior articular facets of the assimilated atlas presented asymmetrical orientation compared to the normal anatomy of the atlas. Hence, in the case of occipitalization, the gap between the articulating facets of the atlas and the axis was measured to be greater than in the normal atlanto-axial joint. Computer assisted tomography was applied to visualise the anatomical relationship between the inferior articular facets of the assimilated atlas and the corresponding facets located on the axis. In this case, radiographic examination revealed that the bilaterally articulating facets (inferior and superior) showed disproportion in their adjustment within the lateral atlanto-axial joints. Thus, we concluded that the fusion of the atlas with the occipital bone altered the geometry of the inferior articular facets of the atlas and influenced the orientation of the superior articular facets of the axis.

  4. 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.

  5. Osteochondral defect repair using a polyvinyl alcohol-polyacrylic acid (PVA-PAAc) hydrogel.

    Science.gov (United States)

    Bichara, David A; Bodugoz-Sentruk, Hatice; Ling, Doris; Malchau, Erik; Bragdon, Charles R; Muratoglu, Orhun K

    2014-08-01

    Poly(vinyl alcohol) (PVA) hydrogels can be candidates for articular cartilage repair due to their high water content. We synthesized a PVA-poly(acrylic acid) (PAAc) hydrogel formulation and determined its ability to function as a treatment option for condylar osteochondral (OC) defects in a New Zealand white rabbit (NZWR) model for 12 weeks and 24 weeks. In addition to hydrogel OC implants, tensile bar-shaped hydrogels were also implanted subcutaneously to evaluate changes in mechanical properties as a function of in vivo duration. There were no statistically significant differences (p > 0.05) in the water content measured in the OC hydrogel implant that was harvested after 12 weeks and 24 weeks, and non-implanted controls. There were no statistically significant differences (p > 0.05) in the break stress, strain at break or modulus of the tensile bars either between groups. Histological analysis of the OC defect, synovial capsule and fibrous tissue around the tensile bars determined hydrogel biocompatibility. Twelve-week hydrogels were found to be in situ flush with the articular cartilage; meniscal tissue demonstrated an intact surface. Twenty-four week hydrogels protruded from the defect site due to lack of integration with subchondral tissue, causing fibrillation to the meniscal surface. Condylar micro-CT scans ruled out osteolysis and bone cysts of the subchondral bone, and no PVA-PAAc hydrogel contents were found in the synovial fluid. The PVA-PAAc hydrogel was determined to be fully biocompatible, maintained its properties over time, and performed well at the 12 week time point. Physical fixation of the PVA-PAAc hydrogel to the subchondral bone is required to ensure long-term performance of hydrogel plugs for OC defect repair.

  6. Parathyroid hormone-related protein is induced by hypoxia and promotes expression of the differentiated phenotype of human articular chondrocytes.

    Science.gov (United States)

    Pelosi, Michele; Lazzarano, Stefano; Thoms, Brendan L; Murphy, Chris L

    2013-11-01

    PTHrP (parathyroid hormone-related protein) is crucial for normal cartilage development and long bone growth and acts to delay chondrocyte hypertrophy and terminal differentiation in the growth plate. After growth plate closure adult HACs (human articular chondrocytes) still produce PTHrP, suggesting a possible role for this factor in the permanent articular cartilage. However, the expression regulation and function of PTHrP in the permanent articular cartilage is unknown. Human articular cartilage is an avascular tissue and functions in a hypoxic environment. The resident chondrocytes have adapted to hypoxia and use it to drive their tissue-specific functions. In the present study, we explored directly in normal articular chondrocytes isolated from a range of human donors the effect of hypoxia on PTHrP expression and whether PTHrP can regulate the expression of the permanent articular chondrocyte phenotype. We show that in HACs PTHrP is up-regulated by hypoxia in a HIF (hypoxia-inducible factor)-1α and HIF-2α-dependent manner. Using recombinant PTHrP, siRNA-mediated depletion of endogenous PTHrP and by blocking signalling through its receptor [PTHR1 (PTHrP receptor 1)], we show that hypoxia-induced PTHrP is a positive regulator of the key cartilage transcription factor SOX9 [SRY (sex determining region on the Y chromosome)-box 9], leading to increased COL2A1 (collagen type II, α1) expression. Our findings thus identify PTHrP as a potential factor for cartilage repair therapies through its ability to promote the differentiated HAC phenotype.

  7. Hypospadias repair

    Science.gov (United States)

    ... the problem. If the repair is not done, problems may occur later on such as: Difficulty controlling and directing urine stream A curve in the penis during erection Decreased fertility Embarrassment about appearance of penis Surgery ...

  8. Arthroscopic laser in intra-articular knee cartilage disorders

    Science.gov (United States)

    Nosir, Hany R.; Siebert, Werner E.

    1996-12-01

    Different assemblies have endeavored to develop arthroscopic laser surgery. Various lasers have been tried in the treatment of orthopaedic problems, and the most useful has turned out to be the Hol-YAG laser 2.1 nm which is a near- contact laser. By using the laser as a powerful tool, and cutting back on the power level, one is able to better achieve the desired treatment effect. Clinical studies to evaluating the role of the laser in different arthroscopic knee procedures, comparing to conventional techniques, showed that the overall outcome attains a momentous confidence level which is shifted to the side of the laser versus the conventional for all maneuvers, barring meniscectomy where there is not perceiving disparity between laser versus the conventional. Meniscectomy continues to be one of the most commonly performed orthopaedic procedures. Laser provides a single tool which can ablate and debride meniscal rims with efficiency and safety. Chondroplasty can also be accomplished with ease using defocused laser energy. Both lateral release and soft tissue cermilization benefit from the cutting effect of laser along with its hemostatic effect. Synovial reduction with a defocused laser is also easily accomplished. By one gadget, one can cut, ablate, smooth, coagulate, congeal and with authentic tissue depth control The future of laser arthroscopic surgery lies in its ability to weld or repair tissues. Our research study has shown that laser activated photoactive dyes can produce a molecular bonding of collagen fibers, and therefore a repair 'weld' can be achieved with both meniscal tissues and with articular cartilage lesions.

  9. What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

    Science.gov (United States)

    Bonnan, Matthew F; Wilhite, D Ray; Masters, Simon L; Yates, Adam M; Gardner, Christine K; Aguiar, Adam

    2013-01-01

    Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods) plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators), showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.

  10. What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

    Directory of Open Access Journals (Sweden)

    Matthew F Bonnan

    Full Text Available Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators, showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.

  11. The minor collagens in articular cartilage

    DEFF Research Database (Denmark)

    Luo, Yunyun

    2017-01-01

    Articular cartilage is a connective tissue consisting of a specialized extracellular matrix (ECM) that dominates the bulk of its wet and dry weight. Type II collagen and aggrecan are the main ECM proteins in cartilage. However, little attention has been paid to less abundant molecular components......, especially minor collagens, including type IV, VI, IX, X, XI, XII, XIII, and XIV, etc. Although accounting for only a small fraction of the mature matrix, these minor collagens not only play essential structural roles in the mechanical properties, organization, and shape of articular cartilage, but also...... fulfil specific biological functions. Genetic studies of these minor collagens have revealed that they are associated with multiple connective tissue diseases, especially degenerative joint disease. The progressive destruction of cartilage involves the degradation of matrix constituents including...

  12. Pure waterjet drilling of articular bone

    OpenAIRE

    Biskup, Christian; Dunnen, Steven den; Kraaij, Gert; Kerkhoffs, Gino M. M. J.; Tuijthof, Gabrielle J. M.

    2015-01-01

    The clinical application of waterjet technology for machining tough human tissues, such as articular bone, has advantages, as it produces clean sharp cuts without tissue heating. Additionally, water supply is possible via flexible tubing, which enables minimally invasive surgical access. This pilot study investigates whether drilling bony tissue with pure waterjets is feasible. Water pressures between 20 and 120 MPa with an orifice of 0.6 mm were used to create waterjets to drill blind boring...

  13. Oxygen, nitric oxide and articular cartilage

    Directory of Open Access Journals (Sweden)

    B Fermor

    2007-04-01

    Full Text Available Molecular oxygen is required for the production of nitric oxide (NO, a pro-inflammatory mediator that is associated with osteoarthritis and rheumatoid arthritis. To date there has been little consideration of the role of oxygen tension in the regulation of nitric oxide production associated with arthritis. Oxygen tension may be particularly relevant to articular cartilage since it is avascular and therefore exists at a reduced oxygen tension. The superficial zone exists at approximately 6% O2, while the deep zone exists at less than 1% O2. Furthermore, oxygen tension can alter matrix synthesis, and the material properties of articular cartilage in vitro.The increase in nitric oxide associated with arthritis can be caused by pro-inflammatory cytokines and mechanical stress. Oxygen tension significantly alters endogenous NO production in articular cartilage, as well as the stimulation of NO in response to both mechanical loading and pro-inflammatory cytokines. Mechanical loading and pro-inflammatory cytokines also increase the production of prostaglandin E2 (PGE2. There is a complex interaction between NO and PGE2, and oxygen tension can alter this interaction. These findings suggest that the relatively low levels of oxygen within the joint may have significant influences on the metabolic activity, and inflammatory response of cartilage as compared to ambient levels. A better understanding of the role of oxygen in the production of inflammatory mediators in response to mechanical loading, or pro-inflammatory cytokines, may aid in the development of strategies for therapeutic intervention in arthritis.

  14. Intra-articular temperatures of the knee in sports – An in-vivo study of jogging and alpine skiing

    Directory of Open Access Journals (Sweden)

    Cerulli Guiliano

    2008-04-01

    Full Text Available Abstract Background Up to date, no information exists about the intra-articular temperature changes of the knee related to activity and ambient temperature. Methods In 6 healthy males, a probe for intra-articular measurement was inserted into the notch of the right knee. Each subject was jogging on a treadmill in a closed room at 19°C room temperature and skiing in a ski resort at -3°C outside temperature for 60 minutes. In both conditions, temperatures were measured every fifteen minutes intra-articulary and at the skin surface of the knee. A possible influence on joint function and laxity was evaluated before and after activity. Statistical analysis of intra-articular and skin temperatures was done using nonparametric Wilcoxon's sign rank sum test and Mann-Whitney's-U-Test. Results Median intra-articular temperatures increased from 31.4°C before activity by 2.1°C, 4°C, 5.8°C and 6.1°C after 15, 30, 45 and 60 min of jogging (all p ≤ 0.05. Median intra-articular temperatures dropped from 32.2°C before activity by 0.5°C, 1.9°C, 3.6°C and 1.1°C after 15, 30, 45 and 60 min of skiing (all n.s.. After 60 minutes of skiing (jogging, the median intra-articular temperature was 19.6% (8.7% higher than the skin surface temperature at the knee. Joint function and laxity appeared not to be different before and after activity within both groups. Conclusion This study demonstrates different changes of intra-articular and skin temperatures during sports in jogging and alpine skiing and suggests that changes are related to activity and ambient temperature.

  15. The effect of surface roughness on repair bond strength of light-curing composite resin to polymer composite substrate.

    Science.gov (United States)

    Kallio, Timo T; Tezvergil-Mutluay, Arzu; Lassila, Lippo V J; Vallittu, Pekka K

    2013-01-01

    The purpose of this study was to analyze the shear bond strength of a new composite resin to polymer-based composite substrates using various surface roughnesses and two kinds of polymer matrices. Particulate filler composite resin with cross-linked polymer matrix and fiber-reinforced composite with semi-interpenetrating polymer matrix were used as bonding substrates after being ground to different roughnesses. Substrates were aged in water for one week before bonding to new resin composites. Twelve specimens in the substrate groups were ground with grinding papers of four grits; 320, 800, 1200 and 2400. Corresponding values of surface roughness (Ra) varied from 0.09 to 0.40 for the particulate filler composite resin and 0.07 to 0.96 for the fiber-reinforced composite resin. Characteristic shear bond strength between the new resin and particulate filler composite resin was highest (27.8 MPa) with the roughest surface (Weibull modulus: 2.085). Fiber-reinforced composite showed the highest bond strength (20.8 MPa) with the smoothest surface (Weibull modulus: 4.713). We concluded that surface roughness did not increase the bonding of new resin to the substrate of IPN based fiber-reinforced composite, whereas the roughness contributed to bonding the new resin to the particulate filler composite resin with a cross-linked polymer matrix.

  16. Noncontact evaluation of articular cartilage degeneration using a novel ultrasound water jet indentation system.

    Science.gov (United States)

    Lu, M-H; Zheng, Y P; Huang, Q-H; Ling, C; Wang, Q; Bridal, L; Qin, L; Mak, A

    2009-01-01

    We previously reported a noncontact ultrasound water jet indentation system for measuring and mapping tissue mechanical properties. The key idea was to utilize a water jet as an indenter as well as the coupling medium for high-frequency ultrasound. In this paper, the system was employed to assess articular cartilage degeneration, using stiffness ratio as an indicator of the mechanical properties of samples. Both the mechanical and acoustical properties of intact and degenerated bovine patellar articular cartilage (n = 8) were obtained in situ. It was found that the stiffness ratio was reduced by 44 +/- 17% after the articular cartilage was treated by 0.25% trypsin at 37 degrees C for 4 h while no significant difference in thickness was observed between the intact and degenerated samples. A significant decrease of 36 +/- 20% in the peak-to-peak amplitude of ultrasound echoes reflected from the cartilage surface was also found for the cartilage samples treated by trypsin. The results also showed that the stiffness obtained with the new method highly correlated with that measured using a standard mechanical testing protocol. A good reproducibility of the measurements was demonstrated. The present results showed that the ultrasound water jet indentation system may provide a potential tool for the non-destructive evaluation of articular cartilage degeneration by simultaneously obtaining mechanical properties, acoustical properties, and thickness data.

  17. Evaluation of influence of proteoglycans on hydration of articular cartilage with the use of ultrasound

    Directory of Open Access Journals (Sweden)

    Yi-yi YANG

    2015-04-01

    Full Text Available Objective To monitor the changes in hydration behaviour of articular cartilage induced by degradation of proteoglycans, and to explore the effect of proteoglycans on hydration behaviour of articular cartilage by using high-frequency ultrasound. Methods Twelve porcine patellae with smooth cartilage surface were prepared and equally divided into two groups: normal group without any enzyme treatment, and trypsin group they were treated with 0.25% trypsin for 8h to digest proteoglycan in the cartilage. The hydration behaviour of the cartilage tissue was scanned by high-frequency ultrasound system with a central frequency of 25MHz. Parameters including cartilage hydration strain and cartilage thickness were measured. The histopathological changes in the articular cartilage were observed under a light microscope. Results It took approximately 20min to reach equilibrium during the hydration process in the normal cartilages, while proteoglycan-degraded cartilage took only about 5min to achieve equilibrium. The equilibrium strain of normal cartilage was 3.5%±0.5%. The degradation of proteoglycans induced a significant decrease in equilibrium strain (1.8%±0.2%, P0.05. Conclusion Proteoglycans play an important role in hydration behaviour of articular cartilage. The degradation of proteoglycans could induce degeneration of cartilage structure and decrease in hydration behaviour after dehydration. DOI: 10.11855/j.issn.0577-7402.2015.03.03

  18. Effect of low-power helium-neon laser irradiation on 13-week immobilized articular cartilage of rabbits.

    Science.gov (United States)

    Bayat, Mohammad; Ansari, Anayatallah; Hekmat, Hossien

    2004-09-01

    Influence of low-power (632.8 nm, Helium-Neon, 13 J/cm2, three times a week) laser on 13-week immobilized articular cartilage was examined with rabbits knee model. Number of chondrocytes and depth of articular cartilage of experimental group were significantly higher than those of sham irradiated group. Surface morphology of sham-irradiated group had rough prominences, fibrillation and lacunae but surface morphology of experimental group had more similarities to control group than to sham irradiated group. There were marked differences between ultrastructure features of control group and experimental group in comparison with sham irradiated group. Low-power Helium-Neon laser irradiation on 13-week immobilized knee joints of rabbits neutrilized adverse effects of immobilization on articular cartilage.

  19. Effects of intra articular tramadol on articular cartilage and synovium of rats

    OpenAIRE

    Musa Kola; Sennur Uzun; Naciye Dilara Zeybek; Fatma Sarıcaoğlu; Seda Banu Akıncı; Ülkü Aypar; Esin Asan

    2015-01-01

    Objective: To investigate the effects of intra articular tramadol injection on articular cartilage and synovium in rat knee joint.Methods: After Animal Ethical Committee approval, a total of 20 Sprague-Dawley rats were used and divided into 4 groups. Each group was composed of 5 rats. 0.2 ml of tramadol HCl was injected into the right knee joints and left knee joints of all the rats were considered as control. Control side joints received saline injection. Rats were sacrificed with ketamin on...

  20. Femoral hernia repair

    Science.gov (United States)

    Femorocele repair; Herniorrhaphy; Hernioplasty - femoral ... During surgery to repair the hernia, the bulging tissue is pushed back in. The weakened area is sewn closed or strengthened. This repair ...

  1. Undescended testicle repair

    Science.gov (United States)

    Orchidopexy; Inguinal orchidopexy; Orchiopexy; Repair of undescended testicle; Cryptorchidism repair ... first year of life without treatment. Undescended testicle repair surgery is recommended for patients whose testicles do ...

  2. Intra-Articular Osteoid Osteoma Mimicking Juvenile Arthritis

    Directory of Open Access Journals (Sweden)

    Sidi Yaya Traore

    2014-01-01

    Full Text Available In case of intra-articular osteoid osteoma, misdiagnosis as juvenile arthritis may occur, delaying adequate treatment. We report cases of intra-articular osteoid osteomas in children that were misdiagnosed and initially inappropriately treated with intra-articular corticoid injection. Diagnosis of osteoid osteoma was finally given by CT-scan and appropriate treatment by radiofrequency ablation or surgical ablation was performed. Clinicians and radiologists should be aware of the potentially confusing clinical and imaging findings associated with intra-articular osteoid osteoma.

  3. A retrospective analysis of two independent prospective cartilage repair studies : autogenous perichondrial grafting versus subchondral drilling 10 years post-surgery

    NARCIS (Netherlands)

    Bouwmeester, PSJM; Homminga, GN; Bulstra, SK; Geesink, RGT; Kuijer, Roelof

    Background: Experimental data indicate that perichondrial grafting to restore articular cartilage defects will result in repair with hyaline-like cartilage, In contrast, debridement and drilling results in repair with fibro-cartilage. In this retrospective study the long-term clinical results of

  4. T-style keratoprosthesis based on surface-modified poly (2-hydroxyethyl methacrylate) hydrogel for cornea repairs

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Jun [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Sun, Jianguo [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); State Key Laboratory of Molecular Engineering of Polymers, Fudan University (China); Hong, Jiaxu [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Wang, Wentao [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Wei, Anji [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Le, Qihua [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Xu, Jianjiang, E-mail: jianjiang-xu@163.com [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China)

    2015-05-01

    Corneal disease is a common cause of blindness, and keratoplasty is considered as an effective treatment method. However, there is a severe shortage of donor corneas worldwide. This paper presents a novel T-style design of a keratoprosthesis and its preparation methods, in which a mechanically and structurally effective artificial cornea is made based on a poly(2-hydroxyethyl methacrylate) hydrogel. The porous skirt was modified with hyaluronic acid and cationized gelatin, and the bottom of the optical column was coated with poly(ethylene glycol). The physical properties of the T-style Kpro were analyzed using ultraviolet and visible spectrophotometry and electron scanning microscopy. The surface chemical properties were characterized using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface modification in the spongy skirt promoted cell adhesion and produced a firm bond between the corneal tissue and the implant device, while the surface modification in the optic column resisted cell adhesion and prevented retroprosthetic membrane formation. Through improved surgical techniques, the novel T-style keratoprosthesis provides enough mechanical stability to facilitate long-term biointegration with the host environment. In vivo implantation experiments showed that the T-style keratoprosthesis is a promising cornea alternative for patients with severe limbal stem cell deficiency and corneal opacity. - Highlights: • T-style keratoprosthesis was designed and prepared based on a PHEMA hydrogel. • Selective surface modifications effectively regulated cells' selective adhesion. • T-style keratoprosthesis provides enough mechanical stability to facilitate long-term biointegration with host tissues.

  5. DOD Initiatives to Rapidly Transition Advanced Coating and Surface Finishing Technologies for Military Turbine Engine Manufacture and Repair

    Science.gov (United States)

    2005-03-21

    of PEWG Projects Involving Plating, Coating, and Surface Finishing • Advanced thermal spray coatings (HVOF) • Electrospark deposition • Laser...EWI, GEAE, P&W, Rolls-Royce FUNDING SOURCES RTOC STATUS OC-ALC request for FY06 Funding 3/21/2005 22 Other Technologies • Electrospark Deposition for...Aircraft Engines PEWG MANAGER Chuck Alford, Anteon Corp TECHNOLOGY OPPORTUNITY ADVANTAGES: Kinetic spray technologies deposit thick coatings with a

  6. Resin composite repair: Quantitative microleakage evaluation of resin-resin and resin-tooth interfaces with different surface treatments

    OpenAIRE

    Celik, Cigdem; Cehreli, Sevi Burcak; Arhun, Neslihan

    2015-01-01

    Objective: The aim was to evaluate the effect of different adhesive systems and surface treatments on the integrity of resin-resin and resin-tooth interfaces after partial removal of preexisting resin composites using quantitative image analysis for microleakage testing protocol. Materials and Methods: A total of 80 human molar teeth were restored with either of the resin composites (Filtek Z250/GrandioSO) occlusally. The teeth were thermocycled (1000×). Mesial and distal 1/3 parts of the res...

  7. Surface functionalisation of polypropylene hernia-repair meshes by RF-activated plasma polymerisation of acrylic acid and silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Nisticò, Roberto, E-mail: roberto.nistico@unito.it [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy); Rosellini, Andrea [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy); Rivolo, Paola [Politecnico di Torino, Dipartimento di Scienza Applicata e Tecnologia, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Faga, Maria Giulia [CNR-IMAMOTER, Strada delle Cacce 73, 10135 Torino (Italy); Lamberti, Roberta; Martorana, Selanna [Herniamesh S.r.l., Via F.lli Meliga 1/C, 10034 Chivasso (Italy); Castellino, Micaela [Center for Space Human Robotics, Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Virga, Alessandro; Mandracci, Pietro [Politecnico di Torino, Dipartimento di Scienza Applicata e Tecnologia, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Malandrino, Mery; Magnacca, Giuliana [University of Torino, Department of Chemistry and NIS Research Centre, Via P. Giuria 7, 10125 Torino (Italy)

    2015-02-15

    Graphical abstract: - Highlights: • Polypropylene meshes for hernioplasty were surface functionalised via plasma-polymerisation to confer adhesive properties. • Subsequently, silver nanoparticles were loaded to add antibacterial activity. • Materials were physico-chemical characterised and adhesive properties evaluated. - Abstract: Hernia diseases are among the most common and diffuse causes of surgical interventions. Unfortunately, still nowadays there are different phenomena which can cause the hernioplasty failure, for instance post-operative prostheses displacements and proliferation of bacteria in the surgical site. In order to limit these problems, commercial polypropylene (PP) and polypropylene/Teflon (PP/PTFE) bi-material meshes were surface functionalised to confer adhesive properties (and therefore reduce undesired displacements) using polyacrylic acid synthesized by plasma polymerisation (PPAA). A broad physico-chemical and morphological characterisation was carried out and adhesion properties were investigated by means of atomic force microscopy (AFM) used in force/distance (F/D) mode. Once biomedical devices surface was functionalised by PPAA coating, metallic silver nanoparticles (AgNPs) with antimicrobial properties were synthesised and loaded onto the polymeric prostheses. The effect of the PPAA, containing carboxylic functionalities, adhesive coating towards AgNPs loading capacity was verified by means of X-ray photoelectron spectroscopy (XPS). Preliminary measurement of the Ag loaded amount and release in water were also investigated via inductively coupled plasma atomic emission spectroscopy (ICP-AES). Promising results were obtained for the functionalised biomaterials, encouraging future in vitro and in vivo tests.

  8. Viscosupplementation with intra-articular hyaluronic acid for treatment of osteoarthritis in the elderly.

    Science.gov (United States)

    Abate, M; Pulcini, D; Di Iorio, A; Schiavone, C

    2010-01-01

    Osteoarthritis (OA) is very disabling condition in the elderly. The current therapeutic approaches (analgesics, NSAIDs, COX-2 inhibitors, steroids) do not delay the OA progression or reverse joint damage. Moreover, they may cause relevant systemic side effects. Hyaluronic acid (HA) is a physiologic component of the synovial fluid and is reduced in OA joints. Therefore, intra-articular injection of HA, due to its viscoelastic properties and protective effect on articular cartilage and soft tissue surfaces of joints, can restore the normal articular homoeostasis. These effects are evident when HA is properly administered into the articular space; therefore, the use of "image-guided" infiltration techniques is mandatory. Viscosupplementation (VS), with different HA preparations (Low and High molecular weight), can be considered when the patient has not found pain relief from other therapies or is intolerant to analgesics or NSAIDs. A 3-5 doses regimen is usually recommended with 1 week interval between each injection. Several studies have shown the efficacy of HA for the treatment of knee OA, with positive effects on pain, articular function (Western Ontario and Mc Master Universities Osteoarthritis Index [WOMAC], Lequesne Index [LI], Range of Motion [ROM]), subjective global assessment and reduction in NSAIDs consumption. In general, the benefit is evident within 3 months and persists in the following 6-12 months. Encouraging but inconclusive results have also been observed for the treatment of shoulder, carpo-metacarpal, hip and ankle OA. However there is the need of better designed studies to prove the effectiveness of these medications, in order to rule out a placebo effect. The therapy is well tolerated with absence of systemic side effects and only with limited local discomfort.

  9. RESEARCH PROGRESS OF ARTICULAR CARTILAGE SCAFFOLD FOR TISSUE ENGINEERING%关节软骨组织工程支架的研究进展

    Institute of Scientific and Technical Information of China (English)

    刘清宇; 王富友; 杨柳

    2012-01-01

    Objective To review the research progress of articular cartilage scaffold materials and look into the future development prospects. Methods Recent literature about articular cartilage scaffold for tissue engineering was reviewed, and the results from experiments and clinical application about natural and synthetic scaffold materials were analyzed. Results The design of articular cartilage scaffold for tissue engineering is vital to articular cartilage defects repair. The ideal scaffold can promote the progress of the cartilage repair, but the scaffold materials still have their limitations. Conclusion It is necessary to pay more attention to the research of the articular cartilage scaffold, which is significant to the repair of cartilage defects in the future.%目的 对软骨组织工程支架材料的研究现状进行综述,并对其发展前景进行展望.方法 广泛查阅近年来关节软骨组织工程支架的相关文献,并对多种天然生物支架材料和人工合成支架材料的相关实验及临床应用效果进行分析总结.结果 软骨组织工程支架的设计对软骨组织损伤修复成功与否至关重要,理想的软骨支架可以引导并促进新生软骨组织的形成.目前所应用的支架材料均有其局限性.结论 进一步深入研究软骨组织工程支架,对未来临床软骨损伤的修复具有重要意义.

  10. Intestinal obstruction repair

    Science.gov (United States)

    Repair of volvulus; Intestinal volvulus - repair; Bowel obstruction - repair ... Intestinal obstruction repair is done while you are under general anesthesia . This means you are asleep and DO NOT feel pain. ...

  11. Aortic aneurysm repair - endovascular

    Science.gov (United States)

    EVAR; Endovascular aneurysm repair - aorta; AAA repair - endovascular; Repair - aortic aneurysm - endovascular ... Endovascular aortic repair is done because your aneurysm is very large, growing quickly, or is leaking or bleeding. You may have ...

  12. Motorcycle Repair.

    Science.gov (United States)

    Hein, Jim; Bundy, Mike

    This motorcycle repair curriculum guide contains the following ten areas of study: brake systems, clutches, constant mesh transmissions, final drives, suspension, mechanical starting mechanisms, electrical systems, fuel systems, lubrication systems, and overhead camshafts. Each area consists of one or more units of instruction. Each instructional…

  13. Intra-articular membranous interposition detected by MRI in developmental dysplasia of the hip

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, W.; Itoi, Eiji; Sato, Kozo [Akita Univ. (Japan). Dept. of Orthopedic Surgery

    2000-12-01

    Intra-articular membranous interposition was detected by MRI in the hip joint with residual subluxation of a girl aged 5 years 10 months. This structure, which had low signal intensity on both T1- and T2-weighted images, separated the femoral head from the acetabulum. Histological examination revealed chondrometaplasia, which suggested that this interposition might be transformed to a surface cartilaginous tissue of the secondary acetabulum often observed in residual subluxation of the hip. (orig.)

  14. Arthroscopic Knotless Peripheral Ulnar-Sided TFCC Repair.

    Science.gov (United States)

    Geissler, William B

    2015-05-01

    This article describes the indications and technique for all-arthroscopic knotless repair of a peripheral tear to the triangular fibrocartilage complex (TFCC). The advantage of this technique is that it allows repair of the articular disk back to the fovea of the ulna without any suture knots to irritate the patient. The learning curve is steep, but once learned, this technique can be performed very quickly and is faster. There are no knots to irritate the patient, and in the author's opinion, there is quicker pain relief than with other techniques.

  15. Turbine repair process, repaired coating, and repaired turbine component

    Energy Technology Data Exchange (ETDEWEB)

    Das, Rupak; Delvaux, John McConnell; Garcia-Crespo, Andres Jose

    2015-11-03

    A turbine repair process, a repaired coating, and a repaired turbine component are disclosed. The turbine repair process includes providing a turbine component having a higher-pressure region and a lower-pressure region, introducing particles into the higher-pressure region, and at least partially repairing an opening between the higher-pressure region and the lower-pressure region with at least one of the particles to form a repaired turbine component. The repaired coating includes a silicon material, a ceramic matrix composite material, and a repaired region having the silicon material deposited on and surrounded by the ceramic matrix composite material. The repaired turbine component a ceramic matrix composite layer and a repaired region having silicon material deposited on and surrounded by the ceramic matrix composite material.

  16. Hyaluronic acid-coated bovine serum albumin nanoparticles loaded with brucine as selective nanovectors for intra-articular injection

    Directory of Open Access Journals (Sweden)

    Chen Z

    2013-10-01

    Full Text Available Zhipeng Chen,* Juan Chen,* Li Wu, Weidong Li, Jun Chen, Haibo Cheng, Jinhuo Pan, Baochang CaiDepartment of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, People's Republic of China*These authors contributed equally to this workObjective: To evaluate the potential of hyaluronic acid (HA-coated bovine serum albumin nanoparticles (BSANPs as a novel chondrocyte-targeting drug-delivery nanomedicine.Methods: The HA-BSANPs were characterized by dynamic light scattering, transmission electron microscopy, differential scanning calorimetry, and X-ray diffraction. Fluorescence imaging was used to visualize the distribution of nanoparticles after intra-articular injection. The chondrocyte-targeting efficiency and cellular uptake mechanism of HA-BSANPs were investigated using endocytic inhibitors.Results: HA-BSANPs were successfully prepared with HA coating the surface and amorphous drug in the core. Compared with BSANPs, HA-BSANPs exhibited improved uptake by chondrocytes through a receptor-mediated active uptake mechanism. The endocytosis process of BSANPs and HA-BSANPs involved clathrin-mediated endocytosis, caveolae-mediated endocytosis, and macropinocytosis. No apparent thickening or hyperplasia of the synovium was observed in either BSANPs or HA-BSANPs. The HA-BSANPs could reside in the articular cavity of rats for more than 14 days, which was significantly longer than BSANPs.Conclusion: HA-BSANPs are a promising carrier for articular-related diseases due to elongated articular residence and improved chondrocytic accumulation.Keywords: chondrocyte, intra-articular injection, hyaluronic acid, BSA, nanoparticles

  17. Mechanical properties of hyaline and repair cartilage studied by nanoindentation.

    Science.gov (United States)

    Franke, O; Durst, K; Maier, V; Göken, M; Birkholz, T; Schneider, H; Hennig, F; Gelse, K

    2007-11-01

    Articular cartilage is a highly organized tissue that is well adapted to the functional demands in joints but difficult to replicate via tissue engineering or regeneration. Its viscoelastic properties allow cartilage to adapt to both slow and rapid mechanical loading. Several cartilage repair strategies that aim to restore tissue and protect it from further degeneration have been introduced. The key to their success is the quality of the newly formed tissue. In this study, periosteal cells loaded on a scaffold were used to repair large partial-thickness cartilage defects in the knee joint of miniature pigs. The repair cartilage was analyzed 26 weeks after surgery and compared both morphologically and mechanically with healthy hyaline cartilage. Contact stiffness, reduced modulus and hardness as key mechanical properties were examined in vitro by nanoindentation in phosphate-buffered saline at room temperature. In addition, the influence of tissue fixation with paraformaldehyde on the biomechanical properties was investigated. Although the repair process resulted in the formation of a stable fibrocartilaginous tissue, its contact stiffness was lower than that of hyaline cartilage by a factor of 10. Fixation with paraformaldehyde significantly increased the stiffness of cartilaginous tissue by one order of magnitude, and therefore, should not be used when studying biomechanical properties of cartilage. Our study suggests a sensitive method for measuring the contact stiffness of articular cartilage and demonstrates the importance of mechanical analysis for proper evaluation of the success of cartilage repair strategies.

  18. Research progress of the effects of compression stimulation on the metabolism of articular chondrocytes and ;mechanical properties%压缩刺激影响关节软骨细胞代谢和力学特性的研究进展

    Institute of Scientific and Technical Information of China (English)

    苑伟; 段王平; 卫小春

    2013-01-01

    Articular cartilages endure a variety of dynamic stresses in a complex physiological environment. As the main force of normal human articular movement, the pressure can change the biological and mechanical properties of chondrocytes, including changes in the stress and strain of articular cartilage tissues, hydrostatic pressure, interstitial fluid flow, flow energy, osmotic pressure, changes of transferring between tissues and cell deformations and so on. Because of the specificity of the mechanical environment, the changes of the mechanical properties of chondrocytes will have an effect on the physiological functions of articular cartilages. It is difficult for articular cartilage injuries caused by many factors to repair themselves, which has brought great difficulties to the clinical treatment. There are many traditional methods of repairing cartilage defects clinically, while some shortcomings exist. Thanks to the development of tissue engineering technology, there is a new idea and method for the regeneration and repair of articular cartilage defects. Scaffold materials are mainly utilized to provide a space structure for the proliferation and matrix secretion of chondrocytes, and a kind of structure is formed similar to normal cartilage tissues to transplant and repair articular cartilage defects. Many factors get involved in the construction of tissue-engineered cartilages with good functions, such as seed cells, scaffold materials, culture conditions and so on, among which mechanical stimulation has a particularly important effect on the metabolism of articular cartilage matrixes and their mechanical properties. Therefore, an intensive study of the mechanical properties of chondrocytes will further clarify a series of processes needed to maintain normal physiological functions, such as the stress conditions and responses. There will be positive signiifcance for the understanding of the biological properties of chondrocytes, the effects of compression

  19. Directing and Potentiating Stem Cell-Mediated Angiogenesis and Tissue Repair by Cell Surface E-Selectin Coating.

    Science.gov (United States)

    Liu, Zhao-Jun; Daftarian, Pirouz; Kovalski, Letícia; Wang, Bo; Tian, Runxia; Castilla, Diego M; Dikici, Emre; Perez, Victor L; Deo, Sapna; Daunert, Sylvia; Velazquez, Omaida C

    2016-01-01

    Stem cell therapy has emerged as a promising approach for treatment of a number of diseases, including delayed and non-healing wounds. However, targeted systemic delivery of therapeutic cells to the dysfunctional tissues remains one formidable challenge. Herein, we present a targeted nanocarrier-mediated cell delivery method by coating the surface of the cell to be delivered with dendrimer nanocarriers modified with adhesion molecules. Infused nanocarrier-coated cells reach to destination via recognition and association with the counterpart adhesion molecules highly or selectively expressed on the activated endothelium in diseased tissues. Once anchored on the activated endothelium, nanocarriers-coated transporting cells undergo transendothelial migration, extravasation and homing to the targeted tissues to execute their therapeutic role. We now demonstrate feasibility, efficacy and safety of our targeted nanocarrier for delivery of bone marrow cells (BMC) to cutaneous wound tissues and grafted corneas and its advantages over conventional BMC transplantation in mouse models for wound healing and neovascularization. This versatile platform is suited for targeted systemic delivery of virtually any type of therapeutic cell.

  20. PRP and Articular Cartilage: A Clinical Update

    Science.gov (United States)

    Rossi, Roberto; Castoldi, Filippo; Michielon, Gianni

    2015-01-01

    The convincing background of the recent studies, investigating the different potentials of platelet-rich plasma, offers the clinician an appealing alternative for the treatment of cartilage lesions and osteoarthritis. Recent evidences in literature have shown that PRP may be helpful both as an adjuvant for surgical treatment of cartilage defects and as a therapeutic tool by intra-articular injection in patients affected by osteoarthritis. In this review, the authors introduce the trophic and anti-inflammatory properties of PRP and the different products of the available platelet concentrates. Then, in a complex scenario made of a great number of clinical variables, they resume the current literature on the PRP applications in cartilage surgery as well as the use of intra-articular PRP injections for the conservative treatment of cartilage degenerative lesions and osteoarthritis in humans, available as both case series and comparative studies. The result of this review confirms the fascinating biological role of PRP, although many aspects yet remain to be clarified and the use of PRP in a clinical setting has to be considered still exploratory. PMID:26075244

  1. PRP and Articular Cartilage: A Clinical Update

    Directory of Open Access Journals (Sweden)

    Antonio Marmotti

    2015-01-01

    Full Text Available The convincing background of the recent studies, investigating the different potentials of platelet-rich plasma, offers the clinician an appealing alternative for the treatment of cartilage lesions and osteoarthritis. Recent evidences in literature have shown that PRP may be helpful both as an adjuvant for surgical treatment of cartilage defects and as a therapeutic tool by intra-articular injection in patients affected by osteoarthritis. In this review, the authors introduce the trophic and anti-inflammatory properties of PRP and the different products of the available platelet concentrates. Then, in a complex scenario made of a great number of clinical variables, they resume the current literature on the PRP applications in cartilage surgery as well as the use of intra-articular PRP injections for the conservative treatment of cartilage degenerative lesions and osteoarthritis in humans, available as both case series and comparative studies. The result of this review confirms the fascinating biological role of PRP, although many aspects yet remain to be clarified and the use of PRP in a clinical setting has to be considered still exploratory.

  2. [Extra-articular manifestations of seronegative spondylarthritis].

    Science.gov (United States)

    Cammelli, Daniele

    2006-05-01

    Seronegative spondylarthritis are frequently characterised by extra-articular manifestations. They are frequently in recurrent uveitis. Between the cutaneous manifestations should be mentioned erythema nodosum, typical of inflammatory bowel diseases, and keratoderma blenorrhagicum, in the Reiter's syndrome. Cardiac complications in ankylosing spondylitis (AS) include aortic valvular regurgitation and arrhythmia and, more rarely, mitral valvulopathy, cardiomyopathy and pericarditis. Pulmonary involvement in AS includes ventilatory restrictive syndrome and fibro-bullous disease of the apex. Vertebral osteoporosis is a very important extra-articular manifestation because of the possibility of spontaneous fractures of the vertebrae. Central neurological manifestations include medullary compression from cervical sub-luxation while the most important peripheral involvements are lumbar stenosis and the cauda equina syndrome. Type AA amyloidosis is a rare late complication of the AS, possible cause of death especially in patients with aggressive disease. Kidney complications can be observed as consequences of prolonged anti-inflammatory therapy, but the most frequent renal complications are amyloidosis and mesangial IgA segmental and focal glomerulonephritis.

  3. Combination of plate screw and Steinmann pin in repair of comminuted calcaneal intra-articular and posterosuperior fractures%钢板螺钉结合斯氏针内固定修复粉碎性跟骨关节内伴后上方骨折

    Institute of Scientific and Technical Information of China (English)

    李广峰; 张鑫; 彭勇; 吴献民; 王思成; 杨国庆; 张友忠; 曹中华; 何国云; 尹志峰; 杨笑宇

    2014-01-01

    背景:目前跟骨关节内粉碎性骨折的治疗方案一般选择钢板螺钉内固定,但对于伴有跟骨后上方骨折的病例,往往因为跟腱牵拉及钢板螺钉内固定的薄弱导致骨折复位困难或者复位难以保持。目的:探讨切开复位钢板螺钉结合斯氏针置入内固定在粉碎性跟骨关节内移位骨折伴后上方骨折中的疗效。方法:选取2009年12月至2013年12月上海中冶医院骨科收治的粉碎性跟骨关节内骨折伴跟骨后上方骨折患者40例,随机分为2组。对照组予切开复位钢板螺钉内固定,试验组予切开复位钢板螺钉结合斯氏针内固定。分别于术前、术后4周测量患者GISSANE角、BOHLER角,末次随访时进行MARYLAND足部评分,并进行组内及组间比较。结果与结论:所有患者均获随访,时间9-23个月。两组患者术后4周BOHLER角、GISSANE角均显著大于术前(P <0.05);术后4周试验组BOHLER角、GISSANE角均显著大于对照组(P <0.05)。末次随访时MARYLAND足部评分试验组平均78分,优良率为80%;对照组平均67分,优良率为73%,试验组优良率显著高于对照组(P<0.05)。提示钢板螺钉内固定辅助斯氏针置入固定修复粉碎性跟骨骨折伴有跟骨后上方骨折,可较单纯钢板螺钉置入内固定取得更为满意的关节内骨折及后上方骨折复位,固定牢靠,可早期功能锻炼,术后患肢功能恢复较单纯钢板螺钉内固定较好。%BACKGROUND:The therapeutic regimen of intraarticular calcaneal comminuted fractures commonly selects plate and screw fixation. However, for case of posterosuperior calcaneal fracture, the weakness of achil es tendon stretch and plate screw fixation results in difficulty or maintenance of reduction. OBJECTIVE:To investigate the therapeutic effects of open reduction and internal fixation with steel screw and Steinmann pins for comminuted calcaneal intra-articular and posterosuperior

  4. Serum-free media for articular chondrocytes in vitro expansion

    Institute of Scientific and Technical Information of China (English)

    SHAO Xin-xin; Neil A.Duncan; LIN Lin; FU Xin; ZHANG Ji-ying; YU Chang-long

    2013-01-01

    Background In vitro chondrocyte expansion is a major challenge in cell-based therapy for human articular cartilage repair.Classical culture conditions usually use animal serum as a medium supplement,which raises a number of undesirable questions.In the present study,two kinds of defined,serum-free media were developed to expand chondrocytes in monolayer culture for the purpose of cartilage tissue engineering.Methods Bovine chondrocytes were expanded in serum-free media supplemented with fibroblast growth factor-2 and platelet-derived growth factor or fibroblast growth factor-2 and insulin-like growth factor.Expansion culture in a conventional 10% fetal bovine serum (FBS) medium served as control.Fibronectin coating was used to help cell adhesion in serum-free medium.Next,in vitro three-dimensional pellet culture was used to evaluate the chondrocyte capacity.Cell pellets were expanded in different media to re-express the differentiated phenotype (re-differentiation) and to form cartilaginous tissue.The pellets were assessed by glycosaminoglycans contents,collagen II,collagen I and collagen X immunohistological staining.Results Chondrocytes cultured in serum-free media showed no proliferation difference than cells grown with 10% FBS medium.In addition,chondrocytes expanded in both serum-free media expressed more differentiated phenotypes at the end of monolayer culture,as indicated by higher gene expression ratios of collagen type Ⅱ to collagen type Ⅰ.Pellets derived from chondrocytes cultured in both serum-free media displayed comparable chondrogenic capacities to pellets from cells expanded in 10% FBS medium.Conclusion These findings provide alternative culture approaches for chondrocytes in vitro expansion,which may benefit the clinical use of autologous chondrocytes implantation.

  5. La influencia de la superficie articular y la membrana sinovial en la evolución de pacientes afectos por bloqueo crónico de la articulación temporomandibular tratados mediante artroscopia Influence of the joint surface and the synovial membrane on the evolution of patients affected by chronic temporomandibular joint block who were treated with arthroscopic surgery

    Directory of Open Access Journals (Sweden)

    R. González-García

    2010-03-01

    Full Text Available Introducción: Se ha referido la artroscopia de la articulación temporomandibular (ATM como una técnica efectiva en el tratamiento del bloqueo crónico (BC articular. El propósito del presente estudio es evaluar si el estado de la superficie articular y la membrana sinovial directamente visualizados por artroscopia pueden determinar el resultado posoperatorio de pacientes afectos por BC de la ATM. Pacientes y método: Doscientos cincuenta y siete de 500 pacientes (344 articulaciones cumplieron los criterios de inclusión para BC de la ATM. Para el presente estudio se seleccionaron 172 pacientes con afectación unilateral. Se eligieron los parámetros "sinovitis" y "condromalacia" para la evaluación de la membrana sinovial y la superficie articular, respectivamente. Se establecieron dos grupos de pacientes: a pacientes con afectación leve: sinovitis grados I/II más condromalacia I/II, y b pacientes con afectación grave: sinovitis grados III/IV más condromalacia grados III/IV. Se eligieron el dolor y la máxima apertura oral (MAO interincisal como variables dependientes. Todos los pacientes se revisaron de modo posoperatorio al mes, 3, 6, 12 y 24 meses. Se utilizó la prueba de la "t" de Student para muestras pareadas para comparar los valores medios de dolor (escala visual analógica, EVA y función (MAO, de modo preoperatorio y posoperatorio. Se utilizó la "t" de Student para muestras independientes para la comparación de los diferentes grupos establecidos. Se consideró estadísticamente significativo un valor de p Introduction: Arthroscopy of the temporomandibular joint (TMJ has been considered an effective technique to treat close lock (CL. The purpose of this study is to evaluate if the status of the joint surface and the synovial membrane directly seen via arthroscopy can determine the post operative results of patients with chronic block of the TMJ. Patients and methods: Two hundred and fifty-seven out of the 500 patients (344

  6. Bond strength of repaired amalgam restorations.

    Science.gov (United States)

    Rey, Rosalia; Mondragon, Eduardo; Shen, Chiayi

    2015-01-01

    This in vitro study investigated the interfacial flexural strength (FS) of amalgam repairs and the optimal combination of repair materials and mechanical retention required for a consistent and durable repair bond. Amalgam bricks were created, each with 1 end roughened to expose a fresh surface before repair. Four groups followed separate repair protocols: group 1, bonding agent with amalgam; group 2, bonding agent with composite resin; group 3, mechanical retention (slot) with amalgam; and group 4, slot with bonding agent and amalgam. Repaired specimens were stored in artificial saliva for 1, 10, 30, 120, or 360 days before being loaded to failure in a 3-point bending test. Statistical analysis showed significant changes in median FS over time in groups 2 and 4. The effect of the repair method on the FS values after each storage period was significant for most groups except the 30-day storage groups. Amalgam-amalgam repair with adequate condensation yielded the most consistent and durable bond. An amalgam bonding agent could be beneficial when firm condensation on the repair surface cannot be achieved or when tooth structure is involved. Composite resin can be a viable option for amalgam repair in an esthetically demanding region, but proper mechanical modification of the amalgam surface and selection of the proper bonding system are essential.

  7. Diffusion and near-equilibrium distribution of MRI and CT contrast agents in articular cartilage

    Science.gov (United States)

    Silvast, Tuomo S.; Kokkonen, Harri T.; Jurvelin, Jukka S.; Quinn, Thomas M.; Nieminen, Miika T.; Töyräs, Juha

    2009-11-01

    Charged contrast agents have been used both in vitro and in vivo for estimation of the fixed charge density (FCD) in articular cartilage. In the present study, the effects of molecular size and charge on the diffusion and equilibrium distribution of several magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents were investigated. Full thickness cartilage disks (Ø = 4.0 mm, n = 64) were prepared from fresh bovine patellae. Contrast agent (gadopentetate: Magnevist®, gadodiamide: Omniscan™, ioxaglate: Hexabrix™ or sodium iodide: NaI) diffusion was allowed either through the articular surface or through the deep cartilage. CT imaging of the samples was conducted before contrast agent administration and after 1, 5, 9, 16, 25 and 29 h (and with three samples after 2, 3, 4 and 5 days) diffusion using a clinical peripheral quantitative computed tomography (pQCT) instrument. With all contrast agents, the diffusion through the deep cartilage was slower when compared to the diffusion through the articular surface. With ioxaglate, gadopentetate and gadodiamide it took over 29 h for diffusion to reach the near-equilibrium state. The slow diffusion of the contrast agents raise concerns regarding the validity of techniques for FCD estimation, as these contrast agents may not reach the equilibrium state that is assumed. However, since cartilage composition, i.e. deep versus superficial, had a significant effect on diffusion, imaging of the nonequilibrium diffusion process might enable more accurate assessment of cartilage integrity.

  8. La influencia de la superficie articular y la membrana sinovial en la evolución de pacientes afectos por bloqueo crónico de la articulación temporomandibular tratados mediante artroscopia Influence of the joint surface and the synovial membrane on the evolution of patients affected by chronic temporomandibular joint block who were treated with arthroscopic surgery

    OpenAIRE

    R. González-García; J. Sastre-Pérez; F.J. Rodríguez-Campo

    2010-01-01

    Introducción: Se ha referido la artroscopia de la articulación temporomandibular (ATM) como una técnica efectiva en el tratamiento del bloqueo crónico (BC) articular. El propósito del presente estudio es evaluar si el estado de la superficie articular y la membrana sinovial directamente visualizados por artroscopia pueden determinar el resultado posoperatorio de pacientes afectos por BC de la ATM. Pacientes y método: Doscientos cincuenta y siete de 500 pacientes (344 articulaciones) cumpliero...

  9. Evaluation of magnesium alloys with alternative surface finishing for the proliferation and chondro-differentiation of human mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Trinidad, J; Arruebarrena, G; De Argandona, E Saenz; De Eguino, G Ruiz; Infante, A; RodrIguez, C I, E-mail: jtrinidad@eps.mondragon.edu

    2010-11-01

    Articular cartilage has little capacity for self-repair. As a result, continuous mechanical stress can lead to the degradation of articular cartilage, culminating in progressive damage and joint degeneration. Tissue engineering has arisen as a promising therapeutic approach to cartilage repair. Magnesium alloys are one of the most important metallic biomaterials emerging in this area due to their biocompatibility, bio-absorbability and especially to their mechanical properties. These properties make magnesium alloys a promising biomaterial in the regeneration of cartilage tissue. Objective. This study was undertaken to analyze the influence of surface characteristics of magnesium alloys in the adhesion, proliferation and differentiation of human mesenchymal stem cells (MSCs). Methods. Two commercial magnesium alloys (AZ31B and ZM21) were subjected to different treatments in order to obtain four different surfaces in each alloy. Human MSCs were seeded into the magnesium alloys and analyzed for their proliferation and chondrogenesis differentiation ability. Results. Human MSCs showed a greater proliferation and chondro-differentiation when cultured in the ZM21 magnesium alloy with a surface finishing of fine sanding, polishing, and etching.

  10. Ultrasound elastomicroscopy using water jet and osmosis loading: potentials for assessment for articular cartilage.

    Science.gov (United States)

    Zheng, Yong-Ping; Lu, Min-Hua; Wang, Qing

    2006-12-22

    Research in elasticity imaging typically relies on 1-10 MHz ultrasound. Elasticity imaging at these frequencies can provide strain maps with a resolution in the order of millimeters, but this is not sufficient for applications to skin, articular cartilage, or other fine structures. In this paper, we introduced two methods of ultrasound elastomicroscopy using water jet and osmosis loading for imaging the elasticity of biological soft tissues with high resolutions. In the first system, the specimens were compressed using water jet compression. A water jet was used to couple a focused 20 MHz ultrasound beam into the specimen and meanwhile served as a "soft" indenter. Because there was no additional attenuation when propagating from the ultrasound transducer to the specimen, the ultrasound signal with high signal-to-noise ratio could be collected from the specimens simultaneously with compressing process. The compression was achieved by adjusting the water flow. The pressure measured inside the water pipe and that on the specimen surface was calibrated. This system was easily to apply C-scan over sample surfaces. Experiments on the phantoms showed that this water jet indentation method was reliable to map the tissue stiffness distribution. Results of 1D and 2D scanning on phantoms with different stiffness are reported. In the second system, we used osmotic pressure caused by the ion concentration change in the bathing solutions for the articular cartilage to deform them. When bovine articular cartilage specimens were immerged in solutions with different salt concentration, a 50 MHz focused ultrasound beam was used to monitor the dynamic swelling or shrinkage process. Results showed that the system could reliably map the strain distribution induced by the osmotic loading. We extract intrinsic layered material parameters of the articular cartilage using a triphasic model. In addition to biological tissues, these systems have potential applications for the assessment of

  11. Effects of intra articular tramadol on articular cartilage and synovium of rats

    Directory of Open Access Journals (Sweden)

    Musa Kola

    2015-12-01

    Full Text Available Objective: To investigate the effects of intra articular tramadol injection on articular cartilage and synovium in rat knee joint. Methods: After Animal Ethical Committee approval, a total of 20 Sprague-Dawley rats were used and divided into 4 groups. Each group was composed of 5 rats. 0.2 ml of tramadol HCl was injected into the right knee joints and left knee joints of all the rats were considered as control. Control side joints received saline injection. Rats were sacrificed with ketamin on 1st, 7th, 14th and 21st days and knee joints were removed. Obtained tissue samples were decalcified and were dyed with Hematoxylin-eosin and Masson’s trichrome stain and examined by light microscopy for the presence of inflammation in periarticular area and synovia. Results: Congestion of synovial veins and perivascular cell infiltration were observed in tramadol group on days 1 and 7 (P < 0.05. The inflammation process was replaced by fibrosis on day 14 and fibrosis was significantly decreased on day 21. Conclusion: Intra articular tramadol should be used cautiously, keeping in mind that it may cause synovial inflammation in early phases and fibrosis in late phases. J Clin Exp Invest 2015; 6 (4: 337-342

  12. Scarf Repair of Composite Laminates

    Directory of Open Access Journals (Sweden)

    Xie Zonghong

    2016-01-01

    Full Text Available The use of composite materials, such as carbon-fiber reinforced plastic (CFRP composites, aero-structures has led to an increased need of advanced assembly joining and repair technologies. Adhesive bonded repairs as an alternative to recover full or part of initial strength were investigated. Tests were conducted with the objective of evaluating the effectiveness of techniques used for repairing damage fiber reinforced laminated composites. Failure loads and failure modes were generated and compared with the following parameters: scarf angles, roughness of grind tool and number of external plies. Results showed that scarf angle was the critical parameter and the largest tensile strength was observed with the smallest scarf angle. Besides, the use of external plies at the outer surface could not increase the repairs efficiency for large scarf angle. Preparing the repair surfaces by sanding them with a sander ranging from 60 to 100 grit number had significant effect on the failure load. These results allowed the proposal of design principles for repairing CFRP structures.

  13. Mechanical vibrations increase the proliferation of articular chondrocytes in high-density culture.

    Science.gov (United States)

    Kaupp, J A; Waldman, S D

    2008-07-01

    Tissue engineering is a promising approach for articular cartilage repair; however, it still has proven a challenge to produce tissue from the limited number of cells that can be extracted from a single individual. Relatively few cell expansion methods exist without the problems of dedifferentiation and/or loss of potency. Previously, it has been shown that mechanical vibrations can enhance chondrocyte proliferation in monolayer culture. Thus, it was hypothesized that chondrocytes grown in high-density culture would respond in a similar fashion while maintaining phenotypic stability. Isolated bovine articular chondrocytes were seeded in high-density culture on Millicell filters and subjected to mechanical vibrations 48 h after seeding. Mechanical vibrations enhanced chondrocyte proliferation at frequencies above 350 Hz, with the peak response occurring at a 1g amplitude for a duration of 30 min. Under these conditions, the gene expression of cartilage-specific and dedifferentiation markers (collagen II, collagen I, and aggrecan) were unchanged by the imposed stimulus. To determine the effect of accumulated extracellular matrix (ECM) on this proliferative response, selected cultures were stimulated under the same conditions after varying lengths of preculture. The amount of accumulated ECM (collagen and proteoglycans) decreased this proliferative response, with the cultures becoming insensitive to the stimulus after 1 week of preculture. Thus, mechanical vibration can serve as an effective means preferentially to stimulate the proliferation of chondrocytes during culture, but its effects appear to be limited to the early stages where ECM accumulation is at a minimum.

  14. Corrective osteotomy assisted by computer simulation for a malunited intra-articular fracture of the distal humerus: two case reports.

    Science.gov (United States)

    Oura, Keiichiro; Kunihiro, Oka; Okada, Kiyoshi; Tanaka, Hiroyuki; Murase, Tsuyoshi

    2016-11-01

    Intra-articular malunion after fractures of the distal humerus can cause pain, stiffness and, consequently, osteoarthritis in the long run. Although corrective osteotomy for intra-articular malunion has been reported, it is still technically challenging and needs careful preoperative evaluation and planning. Here, we present two cases of corrective osteotomy assisted by preoperative three-dimensional (3-D) computer simulation. We present two cases of malunited intra-articular fracture of the distal humerus, which was treated by corrective osteotomy with the aid of 3-D computer simulation. One case was initially treated with closed reduction and pinning, and the other was initially treated with open reduction and internal fixation. Both of them had pain and severely limited range of motion in the elbow due to intra-articular malunion. 3-D models of the bilateral humeri were created on a computer using computed tomography (CT) data. The deformity was analyzed by superimposing the model of the affected humerus on the mirrored model of the contralateral normal humerus. Osteotomy, reduction and fixation were simulated preoperatively on the computer. The actual surgery was performed exactly according to the preoperative 3-D computer simulation. The operative procedures were performed successfully according to the computer simulation. Range-of-motion exercises started 3 days and immediately after the surgery in cases 1 and 2, respectively. Two years after surgery, there were no complaints of pain or instability. The range of elbow motion was 5°-140° and 15°-125° in cases 1 and 2, respectively. Plain radiographs and CT scans showed good reconstruction of the articular surface. 3-D computer simulations can be useful in preoperative planning for intra-articular corrective osteotomy for complex malunion of the distal humerus.

  15. Temporomandibular Joint Condylar Changes Following Maxillomandibular Advancement and Articular Disc Repositioning

    Science.gov (United States)

    Goncalves, Joao Roberto; Wolford, Larry Miller; Cassano, Daniel Serra; da Porciuncula, Guilherme; Paniagua, Beatriz; Cevidanes, Lucia Helena

    2014-01-01

    Purpose To evaluate condylar changes 1 year after bimaxillary surgical advancement with or without articular disc repositioning using longitudinal quantitative measurements in 3-dimensional (3D) temporomandibular joint (TMJ) models. Methods Twenty-seven patients treated with maxillomandibular advancement (MMA) underwent cone-beam computed tomography before surgery immediately after surgery and at 1-year follow-up. All patients underwent magnetic resonance imaging before surgery to assess disc displacements. Ten patients without disc displacement received MMA only. Seventeen patients with articular disc displacement received MMA with simultaneous TMJ disc repositioning (MMA-Drep). Pre- and postsurgical 3D models were superimposed using a voxel-based registration on the cranial base. Results The location, direction, and magnitude of condylar changes were displayed and quantified by graphic semitransparent overlays and 3D color-coded surface distance maps. Rotational condylar displacements were similar in the 2 groups. Immediately after surgery, condylar translational displacements of at least 1.5 mm occurred in a posterior, superior, or mediolateral direction in patients treated with MMA, whereas patients treated with MMA-Drep presented more marked anterior, inferior, and mediolateral condylar displacements. One year after surgery, more than half the patients in the 2 groups presented condylar resorptive changes of at least 1.5 mm. Patients treated with MMA-Drep presented condylar bone apposition of at least 1.5 mm at the superior surface in 26.4%, the anterior surface in 23.4%, the posterior surface in 29.4%, the medial surface in 5.9%, or the lateral surface in 38.2%, whereas bone apposition was not observed in patients treated with MMA. Conclusions One year after surgery, condylar resorptive changes greater than 1.5 mm were observed in the 2 groups. Articular disc repositioning facilitated bone apposition in localized condylar regions in patients treated with MMA

  16. [Familial articular chondrocalcinosis: study of an Alsatian family].

    Science.gov (United States)

    Netter, P; Loeuille, D; Jouzeau, J Y; Gillet, P; Peterschmitt, J; Pourel, J; Gaucher, A

    2001-01-01

    Familial articular chondrocalcinosis is a chronic articular disease characterized by acute intermittent attacks of arthritis, presence of calcium pyrophosphate dihydrate crystal in synovial fluid, cartilage and periarticular soft tissue and by x rays calcium deposition in articular cartilage. A family originating from Alsace, with an autosomal dominant transmission has been studied. As in English and Argentinean families, a linkage to the short arm of chromosome 5p has been found. These results suggest that a defective gene at this location may be related to the chondrocalcinosis in these families.

  17. Diamond-like Carbon Film and Its Application on Articular Surface of Artificial Joint for Increasing Wear Resistance%类金刚石薄膜在人工关节摩擦配副表面改性的应用

    Institute of Scientific and Technical Information of China (English)

    邓乔元; 张腾飞; 武冰洁; 李仕莎; 冷永祥; 黄楠

    2016-01-01

    , we proposed to control the formation of biofilm on the surface of the artificial joints through the use of metal ions to promote protein denaturation and decomposition. And this biofilm could prevent corrosion me-dium (Cl-, PO43-) from penetrating into the interface of film and substrate. So the crevice and interface corrosion would be re-strained. And the lifetime of DLC film would be prolonged.

  18. Research on Hot Gunning Repairing in Laboratory

    Institute of Scientific and Technical Information of China (English)

    CAO Feng; LONG Shigang; MENG Qingmin; SUN Jialin; HONG Yanruo

    2003-01-01

    The lining of blast furnace may be damaged partly,so that gunning repair is needed. The bonding strength of boundary surface between the repairing layer and remained lining of blast furnace has been studied by thermal simulation.The factors influencing the bonding strength are the ingredient gunning repair temperature,remained lining condition and water content of gunning refractory.The bonding strength decreases with the increases of remained lining temperature.

  19. Fast spin-echo MR of the articular cartilage in the osteoarthrotic knee. Correlation of MR and arthroscopic findings

    Energy Technology Data Exchange (ETDEWEB)

    Kawahara, Y. [Omura Municipal Establishment Hospital (Japan). Dept. of Radiology; Uetani, M.; Hayashi, K. [Dept. of Radiology, Nagasaki Univ. School of Medicine (Japan); Nakahara, N.; Futagawa, S.; Kinoshita, Y. [Isahaya Insurance General Hospital (Japan). Dept. of Radiology; Doiguchi, Y.; Nishiguchi, M. [Isahaya Insurance General Hospital (Japan). Dept. of Orthopedic Surgery

    1998-03-01

    Purpose: The objective was to assess the efficacy of fast spin-echo (FSE) imaging in the detection of articular cartilage abnormality in osteoarthrosis of the knee. Material and Methods: We studied 356 articular surfaces in 73 knees that had been examined by both MR imaging and arthroscopy. The MR images were obtained with FSE imaging (TR/TE 4200/100) on a 0.5 T unit. The surface abnormalities of the articular cartilage that were detected by MR imaging were compared with the arthroscopic findings. Results: The overall sensitivity and specificity of MR in detecting chondral abnormalities were 60.5% (158/261) and 93.7% (89/95) respectively. MR imaging was more sensitive to the higher grade lesions: 31.8% (34/107) in grade 1; 72.4% (71/98) in grade 2; 93.5% (43/46) in grade 3; and 100% (10/10) in grade 4. The MR and arthroscopic grades were the same in 46.9% (167/356), and differed by no more than 1 grade in 90.2% (321/356) and 2 grades in 99.2% (353/356). The correlation between arthroscopic and MR grading scores was highly significant with a correlation coefficient of 0.705 (p<0.0001). Conclusion: FSE sequence was less sensitive to mild cartilage abnormality but useful in detecting moderate to severe abnormality and in evaluating the degree of articular cartilage abnormality. (orig.).

  20. Intra-articular injection of tenoxicam following temporomandibular joint arthrocentesis: a pilot study.

    Science.gov (United States)

    Aktas, I; Yalcin, S; Sencer, S

    2010-05-01

    This study examined the clinical and radiological effects of intra-articular tenoxicam injection following arthrocentesis and compared them with arthrocentesis alone in patients with disc displacement without reduction (DDwoR). 24 temporomandibular joints (TMJs) in 21 patients with DDwoR were studied. Patients were divided randomly into Group A in which only arthrocentesis was performed (14 TMJs in 14 patients) and Group AT which received arthrocentesis plus intra-articular injection of tenoxicam (10 TMJs in 7 patients). Patients were evaluated before the procedure, on postoperative day 7, then 2, 3, 4 weeks, and 2, 3, 4, 5, 6 months postoperatively. Intensity of joint pain was assessed using a visual analog scale. Maximum mouth opening was recorded at each follow-up. TMJ sounds and palpation scores were noted as positive or negative. Magnetic resonance imaging (MRI) was performed before and 6 months after treatment in both groups. Disc form, disc location during neutral position, reduction with movement, joint effusion, structures of the articular surfaces, and bone marrow anomalies were evaluated all in MRIs. Both treatments succesfully increased maximum mouth opening and reduced TMJ pain; there were no complications. Difference between the groups was not statistically significant and a larger controlled study is necessary to clarify this use of tenoxicam.

  1. T2* mapping of articular cartilage: current status of research and first clinical applications.

    Science.gov (United States)

    Andreisek, Gustav; Weiger, Markus

    2014-01-01

    T2* mapping is a relatively new method for the compositional assessment of the articular cartilage. Typically, a multigradient echo or an ultrashort echo time imaging technique with a range of short and very short echo times is used. In most studies, imaging is performed at a high field strength, that is, 3 and 7 T. Postprocessing includes exponential fitting of relaxation decay and manual region-of-interest-based measurements of T2* times on T2* maps. Detailed analyses of T2* times of articular cartilage have shown distinct T2* components with shorter and longer T2* times. Moreover, there is a zonal distribution with a significant depthwise gradient of T2*, with relatively short times near the osteochondral junction and relatively long times at the cartilage's surface. T2* times of normal articular cartilage at the knee are, when averaged over the whole cartilage thickness and using monoexponential fitting, approximately 20 milliseconds. The results of recent studies have shown a good test-retest as well as interreader and intrareader reliabilities for T2* mapping. This article provides a descriptive review of the current literature, briefly discusses the technique itself, and provides an outlook on future research questions and possible clinical applications.

  2. Eye muscle repair - discharge

    Science.gov (United States)

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  3. Ventral hernia repair

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007661.htm Ventral hernia repair To use the sharing features on this page, please enable JavaScript. Ventral hernia repair is surgery to repair a ventral hernia. ...

  4. Brain aneurysm repair

    Science.gov (United States)

    ... aneurysm repair; Dissecting aneurysm repair; Endovascular aneurysm repair - brain; Subarachnoid hemorrhage - aneurysm ... Your scalp, skull, and the coverings of the brain are opened. A metal clip is placed at ...

  5. The study on the mechanical characteristics of articular cartilage in simulated microgravity

    Institute of Scientific and Technical Information of China (English)

    Hai-Jun Niu; Qing Wang; Yue-Xiang Wang; Ang Li; Lian-Wen Sun; Yan Yan; Fan Fan; De-Yu Li; Yu-Bo Fan

    2012-01-01

    The microgravity environment of a long-term space flight may induce acute changes in an astronaut's musculo-skeletal systems.This study explores the effects of simulated microgravity on the mechanical characteristics of articular cartilage.Six rats underwent tail suspension for 14 days and six additional rats were kept under normal earth gravity as controls.Swelling strains were measured using high-frequency ultrasound in all cartilage samples subject to osmotic loading.Site-specific swelling strain data were used in a triphasic theoretical model of cartilage swelling to determine the uniaxial modulus of the cartilage solid matrix.No severe surface irregularities were found in the cartilage samples obtained from the control or tail-suspended groups.For the tail-suspended group,the thickness of the cartilage at a specified site,as determined by ultrasound echo,showed a minor decrease.The uniaxial modulus of articular cartilage at the specified site decreased significantly,from (6.31 ± 3.37) MPa to (5.05 ± 2.98) MPa (p < 0.05).The histology-stained image of a cartilage sample also showed a reduced number of chondrocytes and decreased degree of matrix staining.These results demonstrated that the 14 d simulated microgravity induced significant effects on the mechanical characteristics of articular cartilage.This study is the first attempt to explore the effects of simulated microgravity on the mechanical characteristics of articular cartilage using an osmotic loading method and a triphasic model.The conclusions may provide reference information for manned space flights and a better understanding of the effects of microgravity on the skeletal system.

  6. The study on the mechanical characteristics of articular cartilage in simulated microgravity

    Science.gov (United States)

    Niu, Hai-Jun; Wang, Qing; Wang, Yue-Xiang; Li, Ang; Sun, Lian-Wen; Yan, Yan; Fan, Fan; Li, De-Yu; Fan, Yu-Bo

    2012-10-01

    The microgravity environment of a long-term space flight may induce acute changes in an astronaut's musculo-skeletal systems. This study explores the effects of simulated microgravity on the mechanical characteristics of articular cartilage. Six rats underwent tail suspension for 14 days and six additional rats were kept under normal earth gravity as controls. Swelling strains were measured using high-frequency ultrasound in all cartilage samples subject to osmotic loading. Site-specific swelling strain data were used in a triphasic theoretical model of cartilage swelling to determine the uniaxial modulus of the cartilage solid matrix. No severe surface irregularities were found in the cartilage samples obtained from the control or tail-suspended groups. For the tail-suspended group, the thickness of the cartilage at a specified site, as determined by ultrasound echo, showed a minor decrease. The uniaxial modulus of articular cartilage at the specified site decreased significantly, from (6.31 ± 3.37)MPa to (5.05 ± 2.98)MPa ( p < 0.05). The histology-stained image of a cartilage sample also showed a reduced number of chondrocytes and decreased degree of matrix staining. These results demonstrated that the 14 d simulated microgravity induced significant effects on the mechanical characteristics of articular cartilage. This study is the first attempt to explore the effects of simulated microgravity on the mechanical characteristics of articular cartilage using an osmotic loading method and a triphasic model. The conclusions may provide reference information for manned space flights and a better understanding of the effects of microgravity on the skeletal system.

  7. Viscoelastic properties of bovine articular cartilage attached to subchondral bone at high frequencies

    Directory of Open Access Journals (Sweden)

    Shepherd Duncan ET

    2009-06-01

    Full Text Available Abstract Background Articular cartilage is a viscoelastic material, but its exact behaviour under the full range of physiological loading frequencies is unknown. The objective of this study was to measure the viscoelastic properties of bovine articular cartilage at loading frequencies of up to 92 Hz. Methods Intact tibial plateau cartilage, attached to subchondral bone, was investigated by dynamic mechanical analysis (DMA. A sinusoidally varying compressive force of between 16 N and 36 N, at frequencies from 1 Hz to 92 Hz, was applied to the cartilage surface by a flat indenter. The storage modulus, loss modulus and phase angle (between the applied force and the deformation induced were determined. Results The storage modulus, E', increased with increasing frequency, but at higher frequencies it tended towards a constant value. Its dependence on frequency, f, could be represented by, E' = Aloge (f + B where A = 2.5 ± 0.6 MPa and B = 50.1 ± 12.5 MPa (mean ± standard error. The values of the loss modulus (4.8 ± 1.0 MPa mean ± standard deviation were much less than the values of storage modulus and showed no dependence on frequency. The phase angle was found to be non-zero for all frequencies tested (4.9 ± 0.6°. Conclusion Articular cartilage is viscoelastic throughout the full range of frequencies investigated. The behaviour has implications for mechanical damage to articular cartilage and the onset of osteoarthritis. Storage modulus increases with frequency, until the plateau region is reached, and has a higher value than loss modulus. Furthermore, loss modulus does not increase with loading frequency. This means that more energy is stored by the tissue than is dissipated and that this effect is greater at higher frequencies. The main mechanism for this excess energy to be dissipated is by the formation of cracks.

  8. Clinical and Laboratory Predictors of Articular Disorders Among HIV ...

    African Journals Online (AJOL)

    population and prevalence rate of articular disorders among. HIV patients in Kenya of 17%. ..... globally, available reports are on the rate of positivity to HIV antibodies among .... dysregulation and the wear and tear that goes with aging may.

  9. Chitosan-glycerol phosphate/blood implants improve hyaline cartilage repair in ovine microfracture defects.

    Science.gov (United States)

    Hoemann, Caroline D; Hurtig, Mark; Rossomacha, Evgeny; Sun, Jun; Chevrier, Anik; Shive, Matthew S; Buschmann, Michael D

    2005-12-01

    Microfracture is a surgical procedure that is used to treat focal articular cartilage defects. Although joint function improves following microfracture, the procedure elicits incomplete repair. As blood clot formation in the microfracture defect is an essential initiating event in microfracture therapy, we hypothesized that the repair would be improved if the microfracture defect were filled with a blood clot that was stabilized by the incorporation of a thrombogenic and adhesive polymer, specifically, chitosan. The objectives of the present study were to evaluate (1) blood clot adhesion in fresh microfracture defects and (2) the quality of the repair, at six months postoperatively, of microfracture defects that had been treated with or without chitosan-glycerol phosphate/blood clot implants, using a sheep model. In eighteen sheep, two 1-cm2 full-thickness chondral defects were created in the distal part of the femur and treated with microfracture; one defect was made in the medial femoral condyle, and the other defect was made in the trochlea. In four sheep, microfracture defects were created bilaterally; the microfracture defects in one knee received no further treatment, and the microfracture defects in the contralateral knee were filled with chitosan-glycerol phosphate/autologous whole blood and the implants were allowed to solidify. Fresh defects in these four sheep were collected at one hour postoperatively to compare the retention of the chitosan-glycerol phosphate/blood clot with that of the normal clot and to define the histologic characteristics of these fresh defects. In the other fourteen sheep, microfracture defects were made in only one knee and either were left untreated (control group; six sheep) or were treated with chitosan-glycerol phosphate/blood implant (treatment group; eight sheep), and the quality of repair was assessed histologically, histomorphometrically, and biochemically at six months postoperatively. In the defects that were examined

  10. Magnetic Resonance Imaging of Cartilage Repair: A Review.

    Science.gov (United States)

    Trattnig, Siegfried; Winalski, Carl S; Marlovits, Stephan; Jurvelin, Jukka S; Welsch, Goetz H; Potter, Hollis G

    2011-01-01

    Articular cartilage lesions are a common pathology of the knee joint, and many patients may benefit from cartilage repair surgeries that offer the chance to avoid the development of osteoarthritis or delay its progression. Cartilage repair surgery, no matter the technique, requires a noninvasive, standardized, and high-quality longitudinal method to assess the structure of the repair tissue. This goal is best fulfilled by magnetic resonance imaging (MRI). The present article provides an overview of the current state of the art of MRI of cartilage repair. In the first 2 sections, preclinical and clinical MRI of cartilage repair tissue are described with a focus on morphological depiction of cartilage and the use of functional (biochemical) MR methodologies for the visualization of the ultrastructure of cartilage repair. In the third section, a short overview is provided on the regulatory issues of the United States Food and Drug Administration (FDA) and the European Medicines Agency (EMEA) regarding MR follow-up studies of patients after cartilage repair surgeries.

  11. The Frictional Coefficient of Bovine Knee Articular Cartilage

    Institute of Scientific and Technical Information of China (English)

    Qian Shan-hua; Ge Shi-rong; Wang Qing-liang

    2006-01-01

    The normal displacement of articular cartilage was measured under load and in sliding, and the coefficient of friction during sliding was measured using a UMT-2 Multi-Specimen Test System. The maximum normal displacement under load and the start-up frictional coefficient have similar tendency of variation with loading time. The sliding speed does not significantly influence the frictional coefficient of articular cartilage.

  12. Blends and Nanocomposite Biomaterials for Articular Cartilage Tissue Engineering

    Science.gov (United States)

    Doulabi, Azadehsadat Hashemi; Mequanint, Kibret; Mohammadi, Hadi

    2014-01-01

    This review provides a comprehensive assessment on polymer blends and nanocomposite systems for articular cartilage tissue engineering applications. Classification of various types of blends including natural/natural, synthetic/synthetic systems, their combination and nanocomposite biomaterials are studied. Additionally, an inclusive study on their characteristics, cell responses ability to mimic tissue and regenerate damaged articular cartilage with respect to have functionality and composition needed for native tissue, are also provided. PMID:28788131

  13. The effect of surface chemical treatment on the fiexural strength of repaired acrylic resins%表面处理对义齿基托修理弯曲强度的影响

    Institute of Scientific and Technical Information of China (English)

    余辉; 阎召民; 郭天文

    2001-01-01

    Objective: To investigate the effect of etching acrylic resin by chemical surface treatment on repair strength. Methods: Forty-eight rectangular specimens(65mm×10mm×2.5mm)were fabricated using heat-cured acrylic resin according to the manufacturer's recommendations for processing, then fractured using a material testing machine. The fractured specimens were divided into six groups equally and randomly. After the fractured surfaces were prepared using a dental bur, the surfaces were treated with three methods, none as controls, painted with a MMA monomer liquid and acetone liquid for 30 seconds. Then half of the fractured specimens were repaired using a heat-cured acrylic resin, the other were repaired using a cold-cured acryic resin. The fiexural strengths were measured using the same testing machine. Results: The flexural strengths of the acetone-treated groups repaired using heat-cured and cold-cured resin respectively were higher than the non-treated and MMA-treated groups repaired using the same kind of resin (P<0.01).The percent age of strength recovery of the strongest group, treated with acetone and repaired by the heat-cured method, was about 94.14%. Repaired with the heat-cured and cold-cured methods, the flexural strengths of the non-treated groups were not significantly different from the MMA-treated groups(P>0.05). The percent age of strength recovery of these groups were ranged from 50%to 60%. Conclusions: Treating the fractured surface of the acrylic resin denture base chemically with acetone can improve the repair strength efficiently.%目的:观察义齿基托树脂断面丙酮化学处理对树脂粘接修理后的弯曲强度的影响。方法:制作48个65mm×10mm×2.5mmPMMA热凝树脂试样,进行上三点弯曲试验,将压断后的试样随机分为6组,断面经常规预备后采用三种表面处理方法:无处理、MMA单体涂刷30s、丙酮涂刷30s,分别用自凝和热凝树脂修理,然后在材料试验机

  14. Difference in vascular patterns between transosseous-equivalent and transosseous rotator cuff repair.

    Science.gov (United States)

    Urita, Atsushi; Funakoshi, Tadanao; Horie, Tatsunori; Nishida, Mutsumi; Iwasaki, Norimasa

    2017-01-01

    Vascularity is the important factor of biologic healing of the repaired tissue. The purpose of this study was to clarify sequential vascular patterns of repaired rotator cuff by suture techniques. We randomized 21 shoulders in 20 patients undergoing arthroscopic rotator cuff repair into 2 groups: transosseous-equivalent repair (TOE group, n = 10) and transosseous repair (TO group, n = 11). Blood flow in 4 regions inside the cuff (lateral articular, lateral bursal, medial articular, and medial bursal), in the knotless suture anchor in the TOE group, and in the bone tunnel in the TO group was measured using contrast-enhanced ultrasound at 1 month, 2 months, 3 months, and 6 months postoperatively. The sequential vascular pattern inside the repaired rotator cuff was different between groups. The blood flow in the lateral articular area at 1 month, 2 months, and 3 months (P = .002, .005, and .025) and that in the lateral bursal area at 2 months (P = .031) in the TO group were significantly greater than those in the TOE group postoperatively. Blood flow was significantly greater for the bone tunnels in the TO group than for the knotless suture anchor in the TOE group at 1 month and 2 months postoperatively (P = .041 and .009). This study clarified that the sequential vascular pattern inside the repaired rotator cuff depends on the suture technique used. Bone tunnels through the footprint may contribute to biologic healing by increasing blood flow in the repaired rotator cuff. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  15. Tribology approach to the engineering and study of articular cartilage.

    Science.gov (United States)

    Wimmer, Markus A; Grad, Sibylle; Kaup, Thomas; Hänni, Markus; Schneider, Erich; Gogolewski, Sylwester; Alini, Mauro

    2004-01-01

    This study has been based on the assumption that articular motion is an important aspect of mechanotransduction in synovial joints. For this reason a new bioreactor concept, able to reproduce joint kinematics more closely, has been designed. The prototype consists of a rotating scaffold and/or cartilage pin, which is pressed onto an orthogonally rotating ball. By oscillating pin and ball in phase difference, elliptical displacement trajectories are generated that are similar to the motion paths occurring in vivo. Simultaneously, dynamic compression may be applied with a linear actuator, while two-step-motors generate the rotation of pin and ball. The whole apparatus is placed in an incubator. The control station is located outside. Preliminary investigations at the gene expression level demonstrated promising results. Compared with free-swelling control and/or simply compression-loaded samples, chondrocyte-seeded scaffolds as well as nasal cartilage explants exposed to interface motion both showed elevated levels of cartilage oligomeric matrix protein mRNA. The final design of the bioreactor will include four individual stations in line, which will facilitate the investigation of motion-initiated effects at the contacting surfaces in more detail.

  16. A study of crystalline biomaterials for articular cartilage bioengineering

    Energy Technology Data Exchange (ETDEWEB)

    Gross-Aviv, Talia [Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Beer Sheva, 84105 (Israel)], E-mail: taliag@bgu.ac.il; DiCarlo, Bryan B. [Department of Bioengineering, Rice University, Houston, TX 77003 (United States)], E-mail: bdicarlo@rice.edu; French, Margaret M. [Department of Bioengineering, Rice University, Houston, TX 77003 (United States)], E-mail: mmfrench@rice.edu; Athanasiou, Kyriacos A. [Department of Bioengineering, Rice University, Houston, TX 77003 (United States)], E-mail: athanasiou@rice.edu; Vago, Razi [Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Beer Sheva, 84105 (Israel)], E-mail: rvago@bgu.ac.il

    2008-12-01

    This study examines the suitability of marine origin coral species, Porites lutea (POR) and the hydrozoan Millepora dichotoma (MIL), for use as novel three dimensional growth matrices in the field of articular cartilage tissue engineering. Therefore, mesenchymal stem cells (MSCs) and chondrocytes were grown on the skeletal material obtained from each of these two organisms to investigate their potential use as three dimensional scaffolding for cartilage tissue growth. Chondrogenic induction of MSCs was achieved by addition of transforming growth factor-{beta}1 (TGF-{beta}1) and insulin growth factor-I (IGF-I). Cell adherence, proliferation, differentiation and tissue development were investigated through six weeks of culture. Cartilage tissue growth and chondrocytic phenotype maintenance of each cell type were examined by cell morphology, histochemical analyses, expression of collagen type II and quantitative measures of glycosaminoglycan (GAG) content. The MSCs and the chondrocytes were shown good adherence to the scaffolds and maintenance of the chondrocytic phenotype in the initial stages of culture. However after two weeks of culture on MIL and three weeks on POR these cultures began to exhibit signs of further differentiation and phenotypic loss. The shown results indicated that POR was a better substrate for chondrocytes phenotype maintenance than MIL. We believe that surface modification of POR combined with mechanical stimuli will provide a suitable environment for chondrogenic phenotype maintenance. Further investigation of POR and other novel coralline biomatrices is indicated and warranted in the field of cartilage tissue engineering applications.

  17. Early health economic modelling of single-stage cartilage repair. Guiding implementation of technologies in regenerative medicine.

    NARCIS (Netherlands)

    de Windt, T.S.; Sorel, J.C.; Vonk, L.A.; Kip, Michelle Maria Aleida; IJzerman, Maarten Joost; Saris, Daniël B.F.

    2016-01-01

    Both the complexity of clinically applied tissue engineering techniques for articular cartilage repair – such as autologous chondrocyte implantation (ACI) – plus increasing healthcare costs, and market competition, are forcing a shift in focus from two-stage to single-stage interventions that are

  18. Mobilidade articular dos dedos não lesados pós-reparo em lesão dos tendões flexores da mão Joint range of motion of uninjured fingers after repairs to flexor tendon injuries of the hand

    Directory of Open Access Journals (Sweden)

    RB Rabelo

    2007-10-01

    Full Text Available OBJETIVO: Verificar a amplitude de movimento (ADM em mãos que sofreram reparo tendinoso dos músculos flexores superficial e profundo dos dedos, comparando os dados de cada dedo na mão lesada e entre mãos lesadas e não lesadas. MÉTODOS: Foi realizada a goniometria ativa em 15 pacientes e 120 dedos, 60 dedos de mãos lesadas e 60 de mãos controle não lesadas. Os sujeitos foram avaliados no momento da retirada da tala gessada, tendo sido realizada a movimentação precoce pelo método de Duran modificado. A partir dos dados goniométricos, foram registrados os valores do índice TAM (Total Active Motion dos dedos nas mãos lesadas e controle. Para análise dos dados, foi acessada a fórmula de índices funcionais proposta pela American Society for Surgery of the Hand (ASSH e para cálculo estatístico, foi escolhido o Modelo de Efeitos Mistos. RESULTADOS: A fórmula da ASSH para os dedos lesados mostrou que 18,33% tiveram a classificação do movimento "bom", 18,33%, "regular" e 63,34%, "pobre". Foram comparadas as médias das medidas em graus de todos os dedos entre si dentro de cada grupo, controle ou lesado, e as médias das medidas entre os grupos, encontrando-se um p-valor significante apenas entre os grupos controle e lesado. Não houve diferença estatística entre o TAM de cada dedo na mão lesada. CONCLUSÃO: Independente de quantos dedos tenham sofrido lesão tendinosa em uma mão, os dedos não lesados também terão suas ADMs ativas diminuídas no período logo após a retirada da imobilização.OBJECTIVE: To assess the range of motion (ROM in hands that underwent tendon repair in the flexor digitorum superficialis and flexor digitorum profundus muscles of the fingers, comparing the data between the fingers on the injured hand, and between the injured and uninjured hands. METHOD: Active goniometry was performed on 15 patients, making a total of 120 fingers (60 on injured hands and 60 on noninjured control hands. The patients

  19. Articular cartilage tissue engineering with plasma-rich in growth factors and stem cells with nano scaffolds

    Science.gov (United States)

    Montaser, Laila M.; Abbassy, Hadeer A.; Fawzy, Sherin M.

    2016-09-01

    The ability to heal soft tissue injuries and regenerate cartilage is the Holy Grail of musculoskeletal medicine. Articular cartilage repair and regeneration is considered to be largely intractable due to the poor regenerative properties of this tissue. Due to their low self-repair ability, cartilage defects that result from joint injury, aging, or osteoarthritis, are the most often irreversible and are a major cause of joint pain and chronic disability. However, current methods do not perfectly restore hyaline cartilage and may lead to the apparition of fibro- or continue hypertrophic cartilage. The lack of efficient modalities of treatment has prompted research into tissue engineering combining stem cells, scaffold materials and environmental factors. The field of articular cartilage tissue engineering, which aims to repair, regenerate, and/or improve injured or diseased cartilage functionality, has evoked intense interest and holds great potential for improving cartilage therapy. Plasma-rich in growth factors (PRGF) and/or stem cells may be effective for tissue repair as well as cartilage regenerative processes. There is a great promise to advance current cartilage therapies toward achieving a consistently successful approach for addressing cartilage afflictions. Tissue engineering may be the best way to reach this objective via the use of stem cells, novel biologically inspired scaffolds and, emerging nanotechnology. In this paper, current and emergent approach in the field of cartilage tissue engineering is presented for specific application. In the next years, the development of new strategies using stem cells, in scaffolds, with supplementation of culture medium could improve the quality of new formed cartilage.

  20. The treatment of the olecranon comminuted fracture by angle stability principle combined with support under the artic-ular surface%角稳定钢板结合关节面下支撑治疗关节面粉碎的尺骨鹰嘴骨折

    Institute of Scientific and Technical Information of China (English)

    王世龙; 汤超亮; 张权; 陈文钧

    2014-01-01

    Objective To evaluate the treatment effects of the olecranon comminuted fracture by the angle stability prin-ciple combined with support under the articular surface. Methods From November 2008 to June 2012, 13 patients (7 male and 6 female, aged from 20 to 77 years) suffered from olecranon comminuted fracture were treated with Synthes anatomy locking com-pression plate and screws combined with Kirschner wires supporting under the articular surface through the posterior median ap-proach. Fractures occurred in the left elbow in 9 and in the right elbow in 4. According to the Mayo classification, 11 cases were classified as Mayo type IIB and 2 as IIIB. According to the Schatzker-Schmeling classification, 2 fractures were type A2, 9 type C, and 2 type D. One patient with type C fracture also had type I coronoid fracture according to Regan and Morrey classification. The Mayo elbow performance index (MEPI) and the shortened disabilities of the arm shoulder and hand (Quick-DASH) were employed to evaluate the functions. All patients took the satisfaction survey and X-ray during the follow-up. Results All patients were fol-lowed-up for 8 to 41 months. The mean ROM of the elbow joint was 112° (range, 65°-140° ), and the mean rotation angle of the forearm was 170° (range, 150°-180°). The mean score for the MEPI was 96 (range, 85-100), excellent 12, good 1. The mean score for the Quick-DASH was 6.2 (range, 0-16.7). In the satisfaction survey, 8 patients were very satisfied, 4 satisfied, 1 common level. All patients took the X-ray during the follow-up and all of them had achieved fracture union completely with the mean time period as 12.7 weeks (range, 11-24 weeks). No cubitus varus, valgus, and instability were found in all patients. No complication, such as infection, ulnar nerve injuries and etc. was found. Five patients complained about mild discomfort caused by internal fixation at 3 months after surgery. Three of them were diagnosed as joint stiffness because of ROM

  1. Binding and lubrication of biomimetic boundary lubricants on articular cartilage.

    Science.gov (United States)

    Samaroo, Kirk J; Tan, Mingchee; Putnam, David; Bonassar, Lawrence J

    2017-03-01

    The glycoprotein, lubricin, is the primary boundary lubricant of articular cartilage and has been shown to prevent cartilage damage after joint injury. In this study, a library of eight bottle-brush copolymers were synthesized to mimic the structure and function of lubricin. Polyethylene glycol (PEG) grafted onto a polyacrylic acid (pAA) core mimicked the hydrophilic mucin-like domain of lubricin, and a thiol terminus anchored the polymers to cartilage surfaces much like lubricin's C-terminus. These copolymers, abbreviated as pAA-g-PEG, rapidly bound to cartilage surfaces with binding time constants ranging from 20 to 39 min, and affected lubrication under boundary mode conditions with coefficients of friction ranging from 0.140 ± 0.024 to 0.248 ± 0.030. Binding and lubrication were highly correlated (r(2)  = 0.89-0.99), showing that boundary lubrication in this case strongly depends on the binding of the lubricant to the surface. Along with time-dependent and dose-dependent behavior, lubrication and binding of the lubricin-mimetics also depended on copolymer structural parameters including pAA backbone length, PEG side chain length, and PEG:AA brush density. Polymers with larger backbone sizes, brush sizes, or brush densities took longer to bind (p lubricate and protect cartilage in vivo. In copolymers with shorter pAA backbones, increasing hydrodynamic size inhibited lubrication (p lubricating efficacy as recombinant lubricins and as such have potential for in vivo treatment of post-traumatic osteoarthritis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:548-557, 2017.

  2. Treatment and Prevention of (Early) Osteoarthritis Using Articular Cartilage Repair—Fact or Fiction? A Systematic Review

    Science.gov (United States)

    de Windt, Tommy S.; Vonk, Lucienne A.; Brittberg, Mats

    2013-01-01

    Early osteoarthritis (OA) is increasingly being recognized in patients who wish to remain active while not accepting the limitations of conservative treatment or joint replacement. The aim of this systematic review was to evaluate the existing evidence for treatment of patients with early OA using articular cartilage repair techniques. A systematic search was performed in EMBASE, MEDLINE, and the Cochrane collaboration. Articles were screened for relevance and appraised for quality. Nine articles of generally low methodological quality (mean Coleman score 58) including a total of 502 patients (mean age range = 36-57 years) could be included. In the reports, both radiological and clinical criteria for early OA were applied. Of all patients included in this review, 75% were treated with autologous chondrocyte implantation. Good short-term clinical outcome up to 9 years was shown. Failure rates varied from 8% to 27.3%. The conversion to total knee arthroplasty rate was 2.5% to 6.5%. Although a (randomized controlled) trial in this patient category with long-term follow-up is needed, the literature suggests autologous chondrocyte implantation could provide good short- to mid-term clinical outcome and delay the need for total knee arthroplasty. The use of standardized criteria for early OA and implementation of (randomized) trials with long-term follow-up may allow for further expansion of the research field in articular cartilage repair to the challenging population with (early) OA. PMID:26069664

  3. Arthoscopy La artroscopia y las lesiones articulares

    Directory of Open Access Journals (Sweden)

    Raúl J. Naranjo

    1991-01-01

    Full Text Available

    A general view is presented on arthroscopy; its history, indications and limitations are described and analyzed; its advantages in comparison with open surgery are emphasized.

    La artroscopia es un procedimiento que permite, mediante un instrumento óptico, evaluar el Interior de las cavidades articulares. Comenzó a desarrollarse como un procedimiento diagnóstico y pronto sus grandes ventajas frente a las exploraciones abiertas aceleraron el desarrollo de las técnicas y del instrumental. La minimización del trauma a los tejidos y la menor morbilidad posoperatoria permiten que la deambulación y la recuperación funcional sean precoces lo cual, sumado a un mejor resultado estético, ha colocado a la artroscopia como procedimiento de elección para el diagnóstico y el tratamiento de múltiples estados patológicos intraarticulares.

  4. Cartilage repair: surgical techniques and tissue engineering using polysaccharide- and collagen-based biomaterials.

    Science.gov (United States)

    Galois, L; Freyria, A M; Grossin, L; Hubert, P; Mainard, D; Herbage, D; Stoltz, J F; Netter, P; Dellacherie, E; Payan, E

    2004-01-01

    Lesions of articular cartilage have a large variety of causes among which traumatic damage, osteoarthritis and osteochondritis dissecans are the most frequent. Replacement of articular defects in joints has assumed greater importance in recent years. This interest results in large part because cartilage defects cannot adequately heal themselves. Many techniques have been suggested over the last 30 years, but none allows the regeneration of the damaged cartilage, i.e. its replacement by a strictly identical tissue. In the first generation of techniques, relief of pain was the main concern, which could be provided by techniques in which cartilage was replaced by fibrocartilage. Disappointing results led investigators to focus on more appropriate bioregenerative approaches using transplantation of autologous cells into the lesion. Unfortunately, none of these approaches has provided a perfect final solution to the problem. The latest generation of techniques, currently in the developmental or preclinical stages, involve biomaterials for the repair of chondral or osteochondral lesions. Many of these scaffolds are designed to be seeded with chondrocytes or progenitor cells. Among natural and synthetic polymers, collagen- and polysaccharide-based biomaterials have been extensively used. For both these supports, studies have shown that chondrocytes maintain their phenotype when cultured in three dimensions. In both types of culture, a glycosaminoglycan-rich deposit is formed on the surface and in the inner region of the cultured cartilage, and type II collagen synthesis is also observed. Dynamic conditions can also improve the composition of such three-dimensional constructs. Many improvements are still required, however, in a number of key aspects that so far have received only scant attention. These aspects include: adhesion/integration of the graft with the adjacent native cartilage, cell-seeding with genetically-modified cell populations, biomaterials that can be

  5. Reduction and fixation via posteromedial and anterolateral approaches for complex tibial fractures associated with collapse of posterolateral articular surface%后内侧联合前外侧入路复位固定治疗后外侧关节面塌陷的复杂胫骨平台骨折

    Institute of Scientific and Technical Information of China (English)

    丁浩亮; 薛子超; 胡传真; 秦晖; 安智全

    2015-01-01

    Objective To explore the treatment of complex tibial fractures associated with collapse of posterolateral articular surface (Schatzker types Ⅵ and Ⅴ) using reduction via posteromedial and anterolateral approaches.Methods From July 2010 to September 2012,19 patients with complex tibial fracture were treated and followed up by our department.They were 11 males and 8 females,with an average age of 49.5 years (range,from 30 to 65 years).Their fractures were classified as Schatzker type Ⅴ in 14 cases and Schatzker type Ⅵ in 5.All fractures involved the posterolateral tibial plateau.They were all reduced via the posteromedial and anterolateral approaches.The posterolateral cortical fragments were pushed anteriorly and a curved reconstruction plate was used to maintain the reduction via the posteromedial approach.An anatomically designed plate was lastly placed on the anterolateral side of the proximal tibia to fix the lateral articular surface of the proximal tibia.The knee function was evaluated by The Hospital fou Special Surgery Score(HSS) at the last follow-ups.Results The mean operation time was 164.7 min (range,from 120 to 280 min).All fractures united clinically and radiographically after an average time of 15.2 weeks (range,from 12 to 18 weeks).No nonunion,injury to the common peroneal nerve,varus deformity,implant failure,or no deep wound infection occurred.At immediate postoperation and one year postoperation,the mean tibial plateau angle (TPA) was 87.2°± 1.0° and 87.1°± 1.1°,and the mean posterior slope angle (PSA) was 7.0° ± 1.1° and 7.0° ± 1.0°,respectively,showing no significant difference between the 2 time points (P > 0.05).At one year postoperation,the average motion of the affected knee was 128.7° (range,from 0 to 135°).The posterolateral tibial articular malreduction (≤2 mm step-off) was seen in 2 patients.The mean HSS score at the last follow-ups was 92.6 (range,from 88 to 97).Conclusions Posterolateral fragments in complex

  6. Wear and damage of articular cartilage with friction against orthopedic implant materials.

    Science.gov (United States)

    Oungoulian, Sevan R; Durney, Krista M; Jones, Brian K; Ahmad, Christopher S; Hung, Clark T; Ateshian, Gerard A

    2015-07-16

    The objective of this study was to measure the wear response of immature bovine articular cartilage tested against glass or alloys used in hemiarthroplasties. Two cobalt chromium alloys and a stainless steel alloy were selected for these investigations. The surface roughness of one of the cobalt chromium alloys was also varied within the range considered acceptable by regulatory agencies. Cartilage disks were tested in a configuration that promoted loss of interstitial fluid pressurization to accelerate conditions believed to occur in hemiarthroplasties. Results showed that considerably more damage occurred in cartilage samples tested against stainless steel (10 nm roughness) and low carbon cobalt chromium alloy (27 nm roughness) compared to glass (10 nm) and smoother low or high carbon cobalt chromium (10 nm). The two materials producing the greatest damage also exhibited higher equilibrium friction coefficients. Cartilage damage occurred primarily in the form of delamination at the interface between the superficial tangential zone and the transitional middle zone, with much less evidence of abrasive wear at the articular surface. These results suggest that cartilage damage from frictional loading occurs as a result of subsurface fatigue failure leading to the delamination. Surface chemistry and surface roughness of implant materials can have a significant influence on tissue damage, even when using materials and roughness values that satisfy regulatory requirements.

  7. Clinical benefits of intra-articular anakinra for arthrofibrosis.

    Science.gov (United States)

    Brown, Christopher A; Toth, Alison P; Magnussen, Bob

    2010-12-01

    Postoperative inflammation and stiffness, as well as the struggle to achieve full range of motion (ROM), following knee surgery is a significant clinical challenge. Interleukin-1 is a crucial mediator of the inflammatory response and development of pathological conditions leading to chronic inflammation. We hypothesized that intra-articular injection of intra-articular anakinra, an IL-1 antagonist, would result in sustained improvements of chronic refractory arthrofibrosis and limited arthrofibrosis of the knee joint. We retrospectively reviewed 8 patients who underwent injection of intra-articular anakinra, 200 mg. Four patients (3 women, 1 man) had intra-articular anakinra for treatment of chronic refractory arthrofibrosis, and 4 patients (4 women) had intra-articular anakinra for limited arthrofibrosis. All 4 of the refractory arthrofibrosis patients had failed conservative treatment with intensive physical therapy, corticosteroid injections, and anti-inflammatory medication. Three of the 4 patients had failed a prior manipulation under anesthesia with lysis of adhesions. All 4 reported improvement in ROM (10°-45°) and swelling, with 75% reporting improvement in pain. Seventy-five percent of these patients returned to prior activity level. All 4 of the limited arthrofibrosis also failed similar attempts at conservative treatment, and 2 of the 4 had failed a prior manipulation under anesthesia with lysis of adhesions. After intra-articular anakinra, all 4 reported improvement in ROM (20°-45°) and swelling, with 80% reporting improvement in pain. Seventy-five percent of these patients were able to return to prior activity level. We found intra-articular anakinra to be effective in this small cohort of patients with refractory arthrofibrosis and limited arthrofibrosis. Copyright 2010, SLACK Incorporated.

  8. Adaptive mechanically controlled lubrication mechanism found in articular joints.

    Science.gov (United States)

    Greene, George W; Banquy, Xavier; Lee, Dong Woog; Lowrey, Daniel D; Yu, Jing; Israelachvili, Jacob N

    2011-03-29

    Articular cartilage is a highly efficacious water-based tribological system that is optimized to provide low friction and wear protection at both low and high loads (pressures) and sliding velocities that must last over a lifetime. Although many different lubrication mechanisms have been proposed, it is becoming increasingly apparent that the tribological performance of cartilage cannot be attributed to a single mechanism acting alone but on the synergistic action of multiple "modes" of lubrication that are adapted to provide optimum lubrication as the normal loads, shear stresses, and rates change. Hyaluronic acid (HA) is abundant in cartilage and synovial fluid and widely thought to play a principal role in joint lubrication although this role remains unclear. HA is also known to complex readily with the glycoprotein lubricin (LUB) to form a cross-linked network that has also been shown to be critical to the wear prevention mechanism of joints. Friction experiments on porcine cartilage using the surface forces apparatus, and enzymatic digestion, reveal an "adaptive" role for an HA-LUB complex whereby, under compression, nominally free HA diffusing out of the cartilage becomes mechanically, i.e., physically, trapped at the interface by the increasingly constricted collagen pore network. The mechanically trapped HA-LUB complex now acts as an effective (chemically bound) "boundary lubricant"--reducing the friction force slightly but, more importantly, eliminating wear damage to the rubbing/shearing surfaces. This paper focuses on the contribution of HA in cartilage lubrication; however, the system as a whole requires both HA and LUB to function optimally under all conditions.

  9. DNA repair. [UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Setlow, R.

    1978-01-01

    Some topics discussed are as follows: difficulty in extrapolating data from E. coli to mammalian systems; mutations caused by UV-induced changes in DNA; mutants deficient in excision repair; other postreplication mechanisms; kinds of excision repair systems; detection of repair by biochemical or biophysical means; human mutants deficient in repair; mutagenic effects of UV on XP cells; and detection of UV-repair defects among XP individuals. (HLW)

  10. Genetic evidence of the regulatory role of parathyroid hormone-related protein in articular chondrocyte maintenance in an experimental mouse model.

    Science.gov (United States)

    Macica, Carolyn; Liang, Guoying; Nasiri, Ali; Broadus, Arthur E

    2011-11-01

    Parathyroid hormone-related protein (PTHrP) regulates the rate of differentiation of growth chondrocytes and is also expressed in articular chondrocytes. This study tested the hypothesis that PTHrP might have a regulatory role in articular chondrocyte maintenance. Control sequences of growth differentiation factor 5 were used to delete PTHrP from articular chondrocytes in the mid-region of mouse articular cartilage. Mice with conditional deletion of PTHrP (knockout [KO]) and littermate control mice were evaluated for degenerative changes using both a time-course design and destabilization of the medial meniscus (DMM) technique. A total histologic score of degenerative changes was determined for the femoral and tibial articular surfaces (total maximum score of 60). The time-course study revealed degenerative changes in only a minority of the KO mice. In the DMM model, male KO mice were highly susceptible to DMM-induced degenerative changes (mean ± SEM total histologic score 45 ± 2.7 in KO mice versus 23 ± 1.4 in controls; P PTHrP normally functions in a feedback loop with Indian hedgehog (IHH), in which a reduction in one signaling partner induces a compensatory increase in the other. A number of phenotypic and functional markers were documented in KO mice to suggest that the IHH-PTHrP axis is capable of compensating in response to a partial Cre-driven PTHrP deletion, a finding that underscores the need to subject the mouse articular cartilage to a destabilizing challenge in order to elicit frankly degenerative findings. PTHrP may regulate articular chondrocyte maintenance in mice. Copyright © 2011 by the American College of Rheumatology.

  11. Method of repairing discontinuity in fiberglass structures

    Science.gov (United States)

    Gelb, L. L.; Helbert, W. B., Jr.; Enie, R. B.; Mulliken, R. F. (Inventor)

    1974-01-01

    Damaged fiberglass structures are repaired by substantially filling the irregular surfaced damaged area with a liquid, self-curing resin, preferably an epoxy resin mixed with chopped fiberglass, and then applying to the resin surface the first of several woven fiberglass swatches which has stitching in a zig-zag pattern parallel to each of its edges and a fringe of warp and fill glass fibers about the edges outward of the stitching. The method is especially applicable to repair of fiberglass rocket engine casings and is particularly advantageous since it restores the repaired fiberglass structure to substantially its original strength without any significant changes in the geometry or mass of the structure.

  12. Neurophysiological basis for neurogenic-mediated articular cartilage anabolism alteration.

    Science.gov (United States)

    Gouze-Decaris, E; Philippe, L; Minn, A; Haouzi, P; Gillet, P; Netter, P; Terlain, B

    2001-01-01

    This study was designed to investigate the pathways involved in neurogenic-mediated articular cartilage damage triggered by a nonsystemic distant subcutaneous or intra-articular inflammation. The cartilage damage was assessed 24 h after subcutaneous or intra-articular complete Freund's adjuvant (CFA) injection measuring patellar proteoglycan (PG) synthesis (ex vivo [Na(2)(35)SO(4)] incorporation) in 96 Wistar rats. Unilateral subcutaneous or intra-articular injection of CFA induced significant decrease (25-29%) in PG synthesis in both patellae. Chronic administration of capsaicin (50 mg. kg(-1). day(-1) during 4 days), which blunted the normal response of C fiber stimulation, prevented the bilateral significant decrease in cartilage synthesis. Similarly, intrathecal injection of MK-801 (10 nmol/day during 5 days), which blocked the glutamatergic synaptic transmission at the dorsal horn of signal originating in primary afferent C fibers, eliminated the CFA-induced PG synthesis decrease in both patellae. Chemical sympathectomy, induced by guanethidine (12.5 mg. kg(-1). day(-1) during 6 wk), also prevented PG synthesis alteration. Finally, compression of the spinal cord at the T3-T5 level had a similar protective effect on the reduction of [Na(2)(35)SO(4)] incorporation. It is concluded that the signal that triggers articular cartilage synthesis damage induced by a distant local inflammation 1) is transmitted through the afferent C fibers, 2) makes glutamatergic synaptic connections with the preganglionic neurons of the sympathetic system, and 3) involves spinal and supraspinal pathways.

  13. Extra-articular Mimickers of Lateral Meniscal Tears

    Science.gov (United States)

    Barker, Joseph U.; Strauss, Eric J.; Lodha, Sameer; Bach, Bernard R.

    2011-01-01

    Context: Lateral meniscus tears are a common entity seen in sports medicine. Although lateral-side knee pain is often the result of a meniscus injury, several extra-articular pathologies share signs and symptoms with a meniscus tear. It is critical for the clinician to be able to identify and understand extra-articular pathologies that can present similar to a lateral meniscus tear. Evidence Acquisition: Data were collected through a thorough review of the literature conducted through a MEDLINE search for all relevant articles between 1980 and February 2010. Study Type: Clinical review. Results: Common extra-articular pathologies that can mimic lateral meniscal tears include iliotibial band syndrome, proximal tibiofibular joint instability, snapping biceps femoris or popliteus tendons, and peroneal nerve compression syndrome or neuritis. The patient history, physical examination features, and radiographic findings can be used to separate these entities from the more common intra-articular knee pathologies. Conclusions: In treating patients who present with lateral-sided knee pain, clinicians should be able to recognize and treat extra-articular pathologies that can present in a similar fashion as lateral meniscus tears. PMID:23015995

  14. Periarticular dextrose prolotherapy instead of intra-articular injection for pain and functional improvement in knee osteoarthritis

    Directory of Open Access Journals (Sweden)

    Rezasoltani Z

    2017-05-01

    groups. Difficulty in walking on flat surfaces or climbing stairs, and sitting and standing pain, were all improved in both groups from 1 to 5 months after treatment.Limitations: WOMAC scores are subjective and could be a limitation of the study.Conclusion: Periarticular prolotherapy has comparable effects on pain and disability due to knee OA to intra-articular injections, while avoiding risks of complications. Keywords: prolotherapy, knee, osteoarthritis, periarticular, acupuncture

  15. Postnatal changes to the mechanical properties of articular cartilage are driven by the evolution of its collagen network

    Directory of Open Access Journals (Sweden)

    AR Gannon

    2015-01-01

    Full Text Available While it is well established that the composition and organisation of articular cartilage dramatically change during skeletal maturation, relatively little is known about how this impacts the mechanical properties of the tissue. In this study, digital image correlation was first used to quantify spatial deformation within mechanically compressed skeletally immature (4 and 8 week old and mature (1 and 3 year old porcine articular cartilage. The compressive modulus of the immature tissue was relatively homogeneous, while the stiffness of mature articular cartilage dramatically increased with depth from the articular surface. Other, well documented, biomechanical characteristics of the tissue also emerged with skeletal maturity, such as strain-softening and a depth-dependent Poisson’s ratio. The most significant changes that occurred with age were in the deep zone of the tissue, where an order of magnitude increase in compressive modulus (from 0.97 MPa to 9.4 MPa for low applied strains was observed from 4 weeks postnatal to skeletal maturity. These temporal increases in compressive stiffness occurred despite a decrease in tissue sulphated glycosaminoglycan content, but were accompanied by increases in tissue collagen content. Furthermore, helium ion microscopy revealed dramatic changes in collagen fibril alignment through the depth of the tissue with skeletal maturity, as well as a fivefold increase in fibril diameter with age. Finally, computational modelling was used to demonstrate how both collagen network reorganisation and collagen stiffening play a key role in determining the final compressive mechanical properties of the tissue. Together these findings provide a unique insight into evolving structure-function relations in articular cartilage.

  16. Controversies in the management of intra-articular fractures of distal humerus in adults

    Directory of Open Access Journals (Sweden)

    Sudhir Babhulkar

    2011-01-01

    cases and these patients did not achieve full flexion and extension. However, all these patients had useful range of function, with 20΀-110΀ of flexion and full pronation-supination. As per the staging system of Caja et al., the results were in the range of excellent to good in 72% cases (n=67, fair in 19% (n=18, and poor in 9% patients (n=9. In the second part of study (n=90 dual plate fixation of both columns by orthogonal methods (n=80 and parallel plate fixation in 10 patients was performed. The results were excellent to good in 78 patients (86%. Conclusions: The high rate of union can be achieved in complex intra-articular fractures of distal humerus if the proper principles of stable fracture fixation are followed, i.e., a posterior transolecranon approach and dual fixation of both columns and restoration of the continuity of articular surface. The stability achieved by this technique permits institution of early intensive physiotherapy to restore elbow function.

  17. Chondroitin sulphate and heparan sulphate sulphation motifs and their proteoglycans are involved in articular cartilage formation during human foetal knee joint development.

    Science.gov (United States)

    Melrose, James; Isaacs, Marc D; Smith, Susan M; Hughes, Clare E; Little, Christopher B; Caterson, Bruce; Hayes, Anthony J

    2012-09-01

    Novel sulphation motifs within the glycosaminoglycan chain structure of chondroitin sulphate (CS) containing proteoglycans (PGs) are associated with sites of growth, differentiation and repair in many biological systems and there is compelling evidence that they function as molecular recognition sites that are involved in the binding, sequestration or presentation of soluble signalling molecules (e.g. morphogens, growth factors and cytokines). Here, using monoclonal antibodies 3B3(-), 4C3 and 7D4, we examine the distribution of native CS sulphation motifs within the developing connective tissues of the human foetal knee joint, both during and after joint cavitation. We show that the CS motifs have broad, overlapping distributions within the differentiating connective tissues before the joint has fully cavitated; however, after cavitation, they all localise very specifically to the presumptive articular cartilage tissue. Comparisons with the labelling patterns of heparan sulphate (HS), HS-PGs (perlecan, syndecan-4 and glypican-6) and FGF-2, molecules with known signalling roles in development, indicate that these also become localised to the future articular cartilage tissue after joint cavitation. Furthermore, they display interesting, overlapping distributions with the CS motifs, reflective of early tissue zonation. The overlapping expression patterns of these molecules at this site suggests they are involved, or co-participate, in early morphogenetic events underlying articular cartilage formation; thus having potential clinical relevance to mechanisms involved in its repair/regeneration. We propose that these CS sulphation motifs are involved in modulating the signalling gradients responsible for the cellular behaviours (proliferation, differentiation, matrix turnover) that shape the zonal tissue architecture present in mature articular cartilage.

  18. REGENERATION OF ARTICULAR CARTILAGE UNDER THE IMPLANTATION OF BONE MATRIX

    Directory of Open Access Journals (Sweden)

    Yuri M. Iryanov, Nikolay A. Kiryanov, Olga V. Dyuriagina , Tatiana Yu. Karaseva, Evgenii A. Karasev

    2015-07-01

    Full Text Available Background: The damage or loss of articular cartilage is costly medical problem. The purpose of this work – morphological analysis of reparative chondrogenesis when implanted in the area of the knee joint cartilage of granulated mineralized bone matrix. Material and Methods: The characteristic features of the knee cartilage regeneration studied experimentally in pubertal Wistar rats after modeling a marginal perforated defect and implantation of granulated mineralized bone matrix obtained according to original technology without heat and demineralizing processing into the injury zone. Results: This biomaterial established to have pronounced chondro- and osteoinductive properties, and to provide prolonged activation of reparative process, accelerated organotypical remodeling and restoration of the articular cartilage injured. Conclusion: The data obtained demonstrate the efficacy of МВМ in clinical practice for the treatment of diseases and injuries of the articular cartilage.

  19. Mesenchymal stem cells in regenerative medicine: Focus on articular cartilage and intervertebral disc regeneration.

    Science.gov (United States)

    Richardson, Stephen M; Kalamegam, Gauthaman; Pushparaj, Peter N; Matta, Csaba; Memic, Adnan; Khademhosseini, Ali; Mobasheri, Reza; Poletti, Fabian L; Hoyland, Judith A; Mobasheri, Ali

    2016-04-15

    Musculoskeletal disorders represent a major cause of disability and morbidity globally and result in enormous costs for health and social care systems. Development of cell-based therapies is rapidly proliferating in a number of disease areas, including musculoskeletal disorders. Novel biological therapies that can effectively treat joint and spine degeneration are high priorities in regenerative medicine. Mesenchymal stem cells (MSCs) isolated from bone marrow (BM-MSCs), adipose tissue (AD-MSCs) and umbilical cord (UC-MSCs) show considerable promise for use in cartilage and intervertebral disc (IVD) repair. This review article focuses on stem cell-based therapeutics for cartilage and IVD repair in the context of the rising global burden of musculoskeletal disorders. We discuss the biology MSCs and chondroprogenitor cells and specifically focus on umbilical cord/Wharton's jelly derived MSCs and examine their potential for regenerative applications. We also summarize key components of the molecular machinery and signaling pathways responsible for the control of chondrogenesis and explore biomimetic scaffolds and biomaterials for articular cartilage and IVD regeneration. This review explores the exciting opportunities afforded by MSCs and discusses the challenges associated with cartilage and IVD repair and regeneration. There are still many technical challenges associated with isolating, expanding, differentiating, and pre-conditioning MSCs for subsequent implantation into degenerate joints and the spine. However, the prospect of combining biomaterials and cell-based therapies that incorporate chondrocytes, chondroprogenitors and MSCs leads to the optimistic view that interdisciplinary approaches will lead to significant breakthroughs in regenerating musculoskeletal tissues, such as the joint and the spine in the near future.

  20. Foetal and postnatal equine articular cartilage development: magnetic resonance imaging and polarised light microscopy

    Directory of Open Access Journals (Sweden)

    C Cluzel

    2013-08-01

    Full Text Available Adult articular cartilage (AC has a well described multizonal collagen structure. Knowledge of foetal AC organisation and development may provide a prototype for cartilage repair strategies, and improve understanding of structural changes in developmental diseases such as osteochondrosis (OC. The objective of this study was to describe normal development of the spatial architecture of the collagen network of equine AC using 1.5 T magnetic resonance imaging (MRI and polarised light microscopy (PLM, at sites employed for cartilage repair studies or susceptible to OC. T2-weighted fast-spin echo (FSE sequences and PLM assessment were performed on distal femoral epiphyses of equine foetuses, foals and adults. Both MRI and PLM revealed an early progressive collagen network zonal organisation of the femoral epiphyses, beginning at 4 months of gestation. PLM revealed that the collagen network of equine foetal AC prior to birth was already organised into an evident anisotropic layered structure that included the appearance of a dense tangential zone in the superficial AC in the youngest specimens, with the progressive development of an underlying transitional zone. A third, increasingly birefringent, radial layer developed in the AC from 6 months of gestation. Four laminae were observed on the MR images in the last third of gestation. These included not only the AC but also the superficial growth plate of the epiphysis. These findings provide novel data on normal equine foetal cartilage collagen development, and may serve as a template for cartilage repair studies in this species or a model for developmental studies of OC.

  1. Intra-Articular Osteotomy for Distal Humerus Malunion

    Directory of Open Access Journals (Sweden)

    René K. Marti

    2009-01-01

    Full Text Available Intra-articular osteotomy is considered in the rare case of malunion after a fracture of the distal humerus to restore humeral alignment and gain a functional arc of elbow motion. Traumatic and iatrogenic disruption of the limited blood flow to the distal end of the humerus resulting in avascular necrosis of capitellum or trochlea is a major pitfall of the this technically challenging procedure. Two cases are presented which illustrate the potential problems of intra-articular osteotomy for malunion of the distal humerus.

  2. bFGF influences human articular chondrocyte differentiation

    DEFF Research Database (Denmark)

    Schmal, H; Zwingmann, J; Fehrenbach, M

    2007-01-01

    FGF concentrations in supernatants of primary human articular chondrocytes peaked immediately after isolation and then declined. In a dose-dependent manner, bFGF enhanced cell amplification and viability. BFGF induced a decrease in the apoptotic cell population, while the number of proliferating cells remained......BACKGROUND: The possible functional role of basic fibroblast growth factor (bFGF) in regulating the mitotic and metabolic activity of primary human articular chondrocytes was investigated. METHODS: [EF1]Chondrocytes were enzymatically isolated from femoral head cartilage, and were cultured in vitro...

  3. El concepto de contacto articular alternativo de la rodilla

    OpenAIRE

    1994-01-01

    La observación radioscópica de la interlínea articular de rodillas de cadáveres sin anomalías anatómicas durante movimientos de abducción y adducción, realizada en estudios previos del autor, permitió apreciar la aparición de pérdida de contacto entre las superficies articulares mediales o laterales respectivamente. El presente artículo tuvo como objetivo rememorar dichos estudios y documentar las apreciaciones visuales mediante el análisis de neumoartrografías seriada...

  4. Articular Contact Mechanics From an Asymptotic Modeling Perspective: a Review

    Directory of Open Access Journals (Sweden)

    Ivan Argatov

    2016-11-01

    Full Text Available In the present paper we review the current state-of-the-art in asymptotic modeling of articular contact. Particular attention has been given to the knee joint contact mechanics with a special emphasis on implications drawn from the asymptotic models, including average characteristics for articular cartilage layer. By listing a number of complicating effects such as transverse anisotropy, nonhomogeneity, variable thickness, nonlinear deformations, shear loading, and bone deformation, which may be accounted for by asymptotic modeling, some unsolved problems and directions for future research are also discussed.

  5. Reemplazo articular temporomandibular debido a queratoquiste odontogénico

    OpenAIRE

    Pedro Angel Peñón Vivas; Humberto Sarracent Pérez; Patricia Moreira Rodríguez

    2013-01-01

    Existen disímiles condiciones que hacen necesario el reemplazo articular temporomandibular; dentro de las más frecuentes se encuentran la anquilosis, la osteoatrosis, estadíos avanzados del Síndrome de disfunción temporomandibular, daño articular postrauma y procesos neoplásicos o tumorales. Los queratoquistes odontógenos que se agrupan para su estudio dentro de los quistes odontogénicos del desarrollo, representan cerca del 7 al 10 por ciento de todos los quistes maxilo-mandibulares. Se dice...

  6. Isolation and characterization of human articular chondrocytes from surgical waste after total knee arthroplasty (TKA)

    Science.gov (United States)

    Gradišnik, Lidija; Gorenjak, Mario; Vogrin, Matjaž

    2017-01-01

    Background Cartilage tissue engineering is a fast-evolving field of biomedical engineering, in which the chondrocytes represent the most commonly used cell type. Since research in tissue engineering always consumes a lot of cells, simple and cheap isolation methods could form a powerful basis to boost such studies and enable their faster progress to the clinics. Isolated chondrocytes can be used for autologous chondrocyte implantation in cartilage repair, and are the base for valuable models to investigate cartilage phenotype preservation, as well as enable studies of molecular features, nature and scales of cellular responses to alterations in the cartilage tissue. Methods Isolation and consequent cultivation of primary human adult articular chondrocytes from the surgical waste obtained during total knee arthroplasty (TKA) was performed. To evaluate the chondrogenic potential of the isolated cells, gene expression of collagen type 2 (COL2), collagen 1 (COL1) and aggrecan (ACAN) was evaluated. Immunocytochemical staining of all mentioned proteins was performed to evaluate chondrocyte specific production. Results Cartilage specific gene expression of COL2 and ACAN has been shown that the proposed protocol leads to isolation of cells with a high chondrogenic potential, possibly even specific phenotype preservation up to the second passage. COL1 expression has confirmed the tendency of the isolated cells dedifferentiation into a fibroblast-like phenotype already in the second passage, which confirms previous findings that higher passages should be used with care in cartilage tissue engineering. To evaluate the effectiveness of our approach, immunocytochemical staining of the evaluated chondrocyte specific products was performed as well. Discussion In this study, we developed a protocol for isolation and consequent cultivation of primary human adult articular chondrocytes with the desired phenotype from the surgical waste obtained during TKA. TKA is a common and very

  7. Isolation and characterization of human articular chondrocytes from surgical waste after total knee arthroplasty (TKA

    Directory of Open Access Journals (Sweden)

    Jakob Naranda

    2017-03-01

    Full Text Available Background Cartilage tissue engineering is a fast-evolving field of biomedical engineering, in which the chondrocytes represent the most commonly used cell type. Since research in tissue engineering always consumes a lot of cells, simple and cheap isolation methods could form a powerful basis to boost such studies and enable their faster progress to the clinics. Isolated chondrocytes can be used for autologous chondrocyte implantation in cartilage repair, and are the base for valuable models to investigate cartilage phenotype preservation, as well as enable studies of molecular features, nature and scales of cellular responses to alterations in the cartilage tissue. Methods Isolation and consequent cultivation of primary human adult articular chondrocytes from the surgical waste obtained during total knee arthroplasty (TKA was performed. To evaluate the chondrogenic potential of the isolated cells, gene expression of collagen type 2 (COL2, collagen 1 (COL1 and aggrecan (ACAN was evaluated. Immunocytochemical staining of all mentioned proteins was performed to evaluate chondrocyte specific production. Results Cartilage specific gene expression of COL2 and ACAN has been shown that the proposed protocol leads to isolation of cells with a high chondrogenic potential, possibly even specific phenotype preservation up to the second passage. COL1 expression has confirmed the tendency of the isolated cells dedifferentiation into a fibroblast-like phenotype already in the second passage, which confirms previous findings that higher passages should be used with care in cartilage tissue engineering. To evaluate the effectiveness of our approach, immunocytochemical staining of the evaluated chondrocyte specific products was performed as well. Discussion In this study, we developed a protocol for isolation and consequent cultivation of primary human adult articular chondrocytes with the desired phenotype from the surgical waste obtained during TKA. TKA is a

  8. Normalization of glenohumeral articular contact pressures after Latarjet or iliac crest bone-grafting.

    Science.gov (United States)

    Ghodadra, Neil; Gupta, Aman; Romeo, Anthony A; Bach, Bernard R; Verma, Nikhil; Shewman, Elizabeth; Goldstein, Jordan; Provencher, Matthew T

    2010-06-01

    Multiple bone-grafting procedures have been described for patients with glenoid bone loss and shoulder instability. The purpose of this study was to investigate the alterations in glenohumeral contact pressure associated with the placement and orientation of Latarjet or iliac crest bone graft augmentation and to compare the amount of glenoid bone reconstruction with two coracoid face orientations. Twelve fresh-frozen cadaver shoulders were tested in static positions of humeral abduction (30 degrees , 60 degrees , and 60 degrees with 90 degrees of external rotation) with a 440-N compressive load. Glenohumeral contact pressure and area were determined sequentially for (1) the intact glenoid; (2) a glenoid with an anterior bone defect involving 15% or 30% of the glenoid surface area; (3) a 30% glenoid defect treated with a Latarjet or iliac crest bone graft placed 2 mm proud, placed flush, or recessed 2 mm in relation to the level of the glenoid; and (4) a Latarjet bone block placed flush and oriented with either the lateral (Latarjet-LAT) or the inferior (Latarjet-INF) surface of the coracoid as the glenoid face. The amount of glenoid bone reconstructed was compared between the Latarjet-LAT and Latarjet-INF conditions. Bone grafts in the flush position restored the mean peak contact pressure to 116% of normal when the iliac crest bone graft was used (p Latarjet-INF bone block was used (p Latarjet-LAT bone block was used (p Latarjet-LAT bone block resulted in mean peak pressures that were significantly higher than those associated with the iliac crest bone graft (p Latarjet-INF bone block (p Latarjet-LAT bone block led to restoration of the glenoid articular contact surface from the 30% defect state to a 5% defect state. Augmentation of the 30% glenoid defect with the Latarjet-INF bone block resulted in complete restoration to the intact glenoid articular surface area. Glenohumeral contact pressure is optimally restored with a flush iliac crest bone graft or with a

  9. MRI findings in injured articular cartilage of the knee correlated with surgical findings

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-ming; PENG Wen-jia; WU Hua; Kacher Daniel; XIA Li-ming; AI Fei; LI Feng; XIONG Wei

    2009-01-01

    Background There is a strong need for quick noninvasive diagnostic technique that can give a valid estimate of the status of the cartilage reliably,discriminating intact cartilage from various grades of impaired cartilage.The goal of this study was to assess the incidence of knee cartilage injuries and compare the accuracy of two-dimension spin echo(2D SE)and fast spin echo(FSE)(conventional MRI),three-dimensional spoiled gradient echo(3D SPGR),three-dimensional fast imaging employing steady state acquisition(3D FIESTA)MR imaging sequences with surgical examination of the articular cartilage.Methods One hundred and thirty-eight knees with history of knee trauma received conventional MRI,3D SPGR and 3D FIESTA MRI examination before surgery,and surgical examination of articular cartilage was used as reference standard.A modified version of the Noyes classification system was applied for the evaluation of the lateral femoral condyle(LFC),medial femoral condyle(MFC),lateral tibial plateau(LTP),medial tibial plateau(MTP),trochlea and patella.The incidence and distributions of different injured grades at different articular surfaces of knee were assessed.A series of assessment indeces of 3D SPGR,3D FIESTA,and the combination of the conventional MRI and 3D SPGR imaging were calculated.Results The incidence of cartilage defects(grade 2 to 4)was 22%(183/828),according to surgical examination.Grade 3 and 4 lesions were absent at the medial tibial plateau.The rates of exact match between the grading results of different MRI procedures and surgical examination were 49% of 3D SPGR,61% of 3D FIESTA,and 82% of the combination of 3D SPGR and conventional MRI.Also,the combination of 3D SPGR and conventional MR imaging provided the highest sensitivity,specificity,accuracy,positive and negative predictive values,at 71%,97%,90%,90% and 90%,respectively.Conclusions For all the articular surfaces of the traumatic knees,about one fifth(22%)were cartilage defects.Both 3D SPGR and 3D

  10. Pectus excavatum repair

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002949.htm Pectus excavatum repair To use the sharing features on this page, please enable JavaScript. Pectus excavatum repair is surgery to correct pectus excavatum . This ...

  11. Magnetic resonance imaging of the femoral trochlea: evaluation of anatomical landmarks and grading articular cartilage in cadaveric knees

    Energy Technology Data Exchange (ETDEWEB)

    Muhle, Claus [Marienhospital Vechta, Department of Radiology, Vechta (Germany); Veterans Affairs Medical Center, Department of Radiology, San Diego, CA (United States); Mo Ahn, Joong [University of Iowa, Department of Radiology, Iowa, IA (United States); Trudell, Debra; Resnick, Donald [Veterans Affairs Medical Center, Department of Radiology, San Diego, CA (United States)

    2008-06-15

    The purpose of the study was to define magnetic resonance imaging (MRI) findings before and after contrast medium opacification of the knee joint in cadaveric specimens to demonstrate anatomical landmarks of the trochlear surface in relation to the neighboring structures, and to evaluate different MRI sequences in the detection of cartilage defects of the trochlear and patellar surface of the knee. The morphology and relationship of the proximal trochlear surface to the prefemoral fat of the distal femur were investigated by use of different MR sequences before and after intra-articular gadolinium administration into the knee joint in ten cadaveric knees. Anatomic sections were subsequently obtained. In addition, evaluation of the articular surface of the trochlea was performed by two independent observers. The cartilage surfaces were graded using a 2-point system, and results were compared with macroscopic findings. Of 40 cartilage surfaces evaluated, histopathologic findings showed 9 normal surfaces, 20 containing partial-thickness defects, and 11 containing full-thickness defects. Compared with macroscopic data, sensitivity of MR sequences for the two reviewers was between 17 and 90%; specificity, 75 and 100%; positive predictive value, 75 and 100%; negative predictive value, 20 and 100%, depending on patellar or trochlea lesions. Interobserver variability for the presence of disease, which was measured using the kappa statistic, was dependent on the MR sequence used between 0.243 and 0.851. Magnetic resonance imaging sequences can be used to evaluate the cartilage of the trochlear surface with less accuracy when compared with the results of grading the articular cartilage of the patella. (orig.)

  12. Correlation between polarization sensitive optical coherence tomography and SHG microscopy in articular cartilage

    Science.gov (United States)

    Zhou, Xin; Ju, Myeong Jin; Huang, Lin; Tang, Shuo

    2017-02-01

    Polarization-sensitive optical coherence tomography (PS-OCT) and second harmonic generation (SHG) microscopy are two imaging modalities with different resolutions, field-of-views (FOV), and contrasts, while they both have the capability of imaging collagen fibers in biological tissues. PS-OCT can measure the tissue birefringence which is induced by highly organized fibers while SHG can image the collagen fiber organization with high resolution. Articular cartilage, with abundant structural collagen fibers, is a suitable sample to study the correlation between PS-OCT and SHG microscopy. Qualitative conjecture has been made that the phase retardation measured by PS-OCT is affected by the relationship between the collagen fiber orientation and the illumination direction. Anatomical studies show that the multilayered architecture of articular cartilage can be divided into four zones from its natural surface to the subchondral bone: the superficial zone, the middle zone, the deep zone, and the calcified zone. The different zones have different collagen fiber orientations, which can be studied by the different slopes in the cumulative phase retardation in PS-OCT. An algorithm is developed based on the quantitative analysis of PS-OCT phase retardation images to analyze the microstructural features in swine articular cartilage tissues. This algorithm utilizes the depth-dependent slope changing of phase retardation A-lines to segment structural layers. The results show good consistency with the knowledge of cartilage morphology and correlation with the SHG images measured at selected depth locations. The correlation between PS-OCT and SHG microscopy shows that PS-OCT has the potential to analyze both the macro and micro characteristics of biological tissues with abundant collagen fibers and other materials that may cause birefringence.

  13. In Vivo Dynamic Deformation of Articular Cartilage in Intact Joints Loaded by Controlled Muscular Contractions.

    Directory of Open Access Journals (Sweden)

    Ziad Abusara

    Full Text Available When synovial joints are loaded, the articular cartilage and the cells residing in it deform. Cartilage deformation has been related to structural tissue damage, and cell deformation has been associated with cell signalling and corresponding anabolic and catabolic responses. Despite the acknowledged importance of cartilage and cell deformation, there are no dynamic data on these measures from joints of live animals using muscular load application. Research in this area has typically been done using confined and unconfined loading configurations and indentation testing. These loading conditions can be well controlled and allow for accurate measurements of cartilage and cell deformations, but they have little to do with the contact mechanics occurring in a joint where non-congruent cartilage surfaces with different material and functional properties are pressed against each other by muscular forces. The aim of this study was to measure in vivo, real time articular cartilage deformations for precisely controlled static and dynamic muscular loading conditions in the knees of mice. Fifty and 80% of the maximal knee extensor muscular force (equivalent to approximately 0.4N and 0.6N produced average peak articular cartilage strains of 10.5±1.0% and 18.3±1.3% (Mean ± SD, respectively, during 8s contractions. A sequence of 15 repeat, isometric muscular contractions (0.5s on, 3.5s off of 50% and 80% of maximal muscular force produced cartilage strains of 3.0±1.1% and 9.6±1.5% (Mean ± SD on the femoral condyles of the mouse knee. Cartilage thickness recovery following mechanical compression was highly viscoelastic and took almost 50s following force removal in the static tests.

  14. Forearm articular proportions and the antebrachial index in Homo sapiens, Australopithecus afarensis and the great apes.

    Science.gov (United States)

    Williams, Frank L'Engle; Cunningham, Deborah L; Amaral, Lia Q

    2015-12-01

    When hominin bipedality evolved, the forearms were free to adopt nonlocomotor tasks which may have resulted in changes to the articular surfaces of the ulna and the relative lengths of the forearm bones. Similarly, sex differences in forearm proportions may be more likely to emerge in bipeds than in the great apes given the locomotor constraints in Gorilla, Pan and Pongo. To test these assumptions, ulnar articular proportions and the antebrachial index (radius length/ulna length) in Homo sapiens (n=51), Gorilla gorilla (n=88), Pan troglodytes (n=49), Pongo pygmaeus (n=36) and Australopithecus afarensis A.L. 288-1 and A.L. 438-1 are compared. Intercept-adjusted ratios are used to control for size and minimize the effects of allometry. Canonical scores axes show that the proximally broad and elongated trochlear notch with respect to size in H. sapiens and A. afarensis is largely distinct from G. gorilla, P. troglodytes and P. pygmaeus. A cluster analysis of scaled ulnar articular dimensions groups H. sapiens males with A.L. 438-1 ulna length estimates, while one A.L. 288-1 ulna length estimate groups with Pan and another clusters most closely with H. sapiens, G. gorilla and A.L. 438-1. The relatively low antebrachial index characterizing H. sapiens and non-outlier estimates of A.L. 288-1 and A.L. 438-1 differs from those of the great apes. Unique sex differences in H. sapiens suggest a link between bipedality and forearm functional morphology.

  15. In Vivo Dynamic Deformation of Articular Cartilage in Intact Joints Loaded by Controlled Muscular Contractions.

    Science.gov (United States)

    Abusara, Ziad; Von Kossel, Markus; Herzog, Walter

    2016-01-01

    When synovial joints are loaded, the articular cartilage and the cells residing in it deform. Cartilage deformation has been related to structural tissue damage, and cell deformation has been associated with cell signalling and corresponding anabolic and catabolic responses. Despite the acknowledged importance of cartilage and cell deformation, there are no dynamic data on these measures from joints of live animals using muscular load application. Research in this area has typically been done using confined and unconfined loading configurations and indentation testing. These loading conditions can be well controlled and allow for accurate measurements of cartilage and cell deformations, but they have little to do with the contact mechanics occurring in a joint where non-congruent cartilage surfaces with different material and functional properties are pressed against each other by muscular forces. The aim of this study was to measure in vivo, real time articular cartilage deformations for precisely controlled static and dynamic muscular loading conditions in the knees of mice. Fifty and 80% of the maximal knee extensor muscular force (equivalent to approximately 0.4N and 0.6N) produced average peak articular cartilage strains of 10.5±1.0% and 18.3±1.3% (Mean ± SD), respectively, during 8s contractions. A sequence of 15 repeat, isometric muscular contractions (0.5s on, 3.5s off) of 50% and 80% of maximal muscular force produced cartilage strains of 3.0±1.1% and 9.6±1.5% (Mean ± SD) on the femoral condyles of the mouse knee. Cartilage thickness recovery following mechanical compression was highly viscoelastic and took almost 50s following force removal in the static tests.

  16. Research Progress in Tissue Engineered Articular Cartilage%组织工程化关节软骨研究进展

    Institute of Scientific and Technical Information of China (English)

    来灿钢; 张泽宇; 李青; 俞燕飞; 厉驹

    2016-01-01

    Articular cartilage is a non-vascular tissue ,the inflammation of articular cartilage is induced by cartilage cels, synovial tissue secretion of cytokines.The way to repair of cartilage defects is always a great chalenge in clinical practice,because of the limited regenerative capacity.Therefore,preferable repair of articular cartilage has been the focus of reconstructive surgery.This article reviews the advancements of the tissue engineered articular cartilage. Construction of tissue-engineered articular cartilage refers to three key factors,including seed cels,scaffolds and cytokines,al of them must be coordinated development and mutual beneift.Research of tissue engineered articular cartilage has made great progress,the tissue engineered articular cartilage has been successfuly applied to clinical, obvious effects have been achieved.Recent development of research on materials,the new material of tissue engineered articular cartilage wil be beter meet the biological characteristics and make breakthrough on damaged cartilage repair.%关节软骨属于无血管的组织,炎症的反应是由软骨细胞、滑膜组织分泌的细胞因子所介导。关节软骨损伤后自身修复能力有限,损伤后的修复成为临床急需解决的问题。因此,关节软骨损伤修复成为研究者和临床工作者的研究热点,本文就目前关节软骨组织工程研究进展作一综述。种子细胞、支架和细胞因子是关节软骨组织工程的三大要素,三者必须协调发展和互利。现阶段组织工程方法修复关节软骨损伤的研究已取得很大进展,组织工程修复关节软骨损伤这项技术已成功应用于临床,取得了明显的效果。随着新材料的不断研发,新的组织工程软骨修复材料将兼顾材料学和生物学的需要,使其更接近机体自身组织生物学特性,使关节软骨损伤修复取得突破性进展。

  17. 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.

  18. When "Other" Initiate Repair.

    Science.gov (United States)

    Schegloff, Emanuel A.

    2000-01-01

    Elaborates on the locus of other-initiated repair, and reports on a number of environments in which others initiate repair turns later than the one directly following the trouble-source turn. Describes several ways that other initiation of repair, which occurs in next-turn position, may be delayed within that position. (Author/VWL)

  19. Wound repair in Pocillopora

    Science.gov (United States)

    Rodríguez-Villalobos, Jenny Carolina; Work, Thierry M.; Calderon-Aguileraa, Luis Eduardo

    2016-01-01

    Corals routinely lose tissue due to causes ranging from predation to disease. Tissue healing and regeneration are fundamental to the normal functioning of corals, yet we know little about this process. We described the microscopic morphology of wound repair in Pocillopora damicornis. Tissue was removed by airbrushing fragments from three healthy colonies, and these were monitored daily at the gross and microscopic level for 40 days. Grossly, corals healed by Day 30, but repigmentation was not evident at the end of the study (40 d). On histology, from Day 8 onwards, tissues at the lesion site were microscopically indistinguishable from adjacent normal tissues with evidence of zooxanthellae in gastrodermis. Inflammation was not evident. P. damicornis manifested a unique mode of regeneration involving projections of cell-covered mesoglea from the surface body wall that anastomosed to form gastrovascular canals.

  20. Autologous, allogeneic, induced pluripotent stem cell or a combination stem cell therapy? Where are we headed in cartilage repair and why: a concise review

    NARCIS (Netherlands)

    Vonk, L.A.; Windt, de T.S.; Slaper-Cortenbach, Ineke C.M.; Saris, D.B.F.

    2015-01-01

    The evolution of articular cartilage repair procedures has resulted in a variety of cell-based therapies that use both autologous and allogeneic mesenchymal stromal cells (MSCs). As these cells are increasingly available and show promising results both in vitro and in vivo, cell-based strategies, wh

  1. Computational aspects in mechanical modeling of the articular cartilage tissue.

    Science.gov (United States)

    Mohammadi, Hadi; Mequanint, Kibret; Herzog, Walter

    2013-04-01

    This review focuses on the modeling of articular cartilage (at the tissue level), chondrocyte mechanobiology (at the cell level) and a combination of both in a multiscale computation scheme. The primary objective is to evaluate the advantages and disadvantages of conventional models implemented to study the mechanics of the articular cartilage tissue and chondrocytes. From monophasic material models as the simplest form to more complicated multiscale theories, these approaches have been frequently used to model articular cartilage and have contributed significantly to modeling joint mechanics, addressing and resolving numerous issues regarding cartilage mechanics and function. It should be noted that attentiveness is important when using different modeling approaches, as the choice of the model limits the applications available. In this review, we discuss the conventional models applicable to some of the mechanical aspects of articular cartilage such as lubrication, swelling pressure and chondrocyte mechanics and address some of the issues associated with the current modeling approaches. We then suggest future pathways for a more realistic modeling strategy as applied for the simulation of the mechanics of the cartilage tissue using multiscale and parallelized finite element method.

  2. Intra-articular regional migratory osteoporosis of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Wambeek, N.; Munk, P.L.; Lee, M.J. [Dept. of Radiology, Vancouver General Hospital, BC (Canada); University of British Columbia, Vancouver (Canada); Meek, R.N. [Department of Orthopedic Surgery, Vancouver General Hospital, Vancouver (Canada)

    2000-02-01

    We report a case of lntra-articular regional migratory osteoporosis of the knee in a 53-year-old man. The case demonstrates an unusual pattern of migration of the marrow edema within the knee joint. This phenomenon has received scant attention in the radiological literature. (orig.)

  3. Vitamin D and Its Effects on Articular Cartilage and Osteoarthritis.

    Science.gov (United States)

    Garfinkel, Rachel J; Dilisio, Matthew F; Agrawal, Devendra K

    2017-06-01

    Osteoarthritis (OA) currently affects 10% of the American population. There has been a recent push to determine exactly what causes OA and how it can be treated most effectively. Serum vitamin D levels have been associated with OA and may have an effect on articular cartilage remodeling. To critically review the published research on the effect of vitamin D on articular cartilage and the development of OA as well as on the mechanism behind cartilage regeneration and degeneration. Review. A systematic search of PubMed and the Web of Science was performed for relevant studies published in the English language through April 30, 2016, using the terms vitamin D, articular cartilage, and osteoarthritis. On a molecular level, 1α,25(OH)2D3, the activated form of vitamin D, plays a role in articular cartilage degeneration. Vitamin D binds to vitamin D receptors, triggering a signaling cascade that leads to chondrocyte hypertrophy. In clinical trials, vitamin D deficiency poses a risk factor for OA, and those with decreased cartilage thickness are more likely to be vitamin D-insufficient. The role of vitamin D supplementation in the treatment or prevention of OA remains uncertain. More research is needed to reconcile these conflicting findings.

  4. The epidemiology of extra-articular manifestations in ankylosing spondylitis

    DEFF Research Database (Denmark)

    Stolwijk, Carmen; Essers, Ivette; van Tubergen, Astrid

    2015-01-01

    OBJECTIVE: To assess the incidence and risks of common extra-articular manifestations (EAMs), that is, acute anterior uveitis (AAU), psoriasis and inflammatory bowel disease (IBD), in patients with ankylosing spondylitis (AS) compared with population-based controls. METHODS: All incident patients...

  5. Sarcoma sinovial extra-articular em cão

    OpenAIRE

    França,S.A.; Serakides,R.; Silva,A.E.; Rachid,M.A.; J.R.C. Moraes; Lavalle,G.E.; Ocarino,N.M.

    2004-01-01

    One four-year-old, female, Collie, dog presented subcutaneous enlarged mass at the lateral aspect of the left hindlimb, close to the knee joint. Based on the anatomopathological and immunohistochemical findings it was confirmed the diagnosis of extra-articular bifasic synovial sarcoma - grade II.

  6. Clinical Outcome Scoring of Intra-articular Calcaneal Fractures

    NARCIS (Netherlands)

    T. Schepers (Tim); M.J. Heetveld (Martin); P.G.H. Mulder (Paul); P. Patka (Peter)

    2008-01-01

    textabstractOutcome reporting of intra-articular calcaneal fractures is inconsistent. This study aimed to identify the most cited outcome scores in the literature and to analyze their reliability and validity. A systematic literature search identified 34 different outcome scores. The most cited outc

  7. Surgery for extra-articular trismus : a systematic review

    NARCIS (Netherlands)

    Bouman, M. A.; Dijkstra, P. U.; Reintsema, H.; Roodenburg, J. L. N.; Werkera, P. M. N.

    The aim of this systematic review was to identify operations that are used to improve mouth opening in patients with extra-articular trismus (caused by cancer and its treatment, oral submucous fibrosis, or noma) and to find out if they work. We searched the electronic databases PubMed, Embase,

  8. Chondrogenic potential of articular chondrocytes depends on their original location

    NARCIS (Netherlands)

    Bekkers, Joris E J; Saris, Daniel B F; Tsuchida, Anika Iris; van Rijen, Mattie H P; Dhert, Wouter J A; Creemers, Laura B

    2014-01-01

    OBJECTIVE: This study aimed to investigate the regenerative capacity of chondrocytes derived from debrided defect cartilage and healthy cartilage from different regions in the joint to determine the best cell source for regenerative cartilage therapies. METHODS: Articular cartilage was obtained from

  9. Percutaneous treatment of displaced intra-articular calcaneal fractures

    NARCIS (Netherlands)

    T. Schepers (Tim); I.B. Schipper (Inger); L.M.M. Vogels (Lucas); A.Z. Ginai (Abida); P.G.H. Mulder (Paul); M.J. Heetveld (Martin); P. Patka (Peter)

    2007-01-01

    textabstractBackground. The outcome after displaced intra-articular calcaneal fractures is influenced by the condition of the surrounding soft tissues. To avoid secondary soft tissue complications after surgical treatment, several less-invasive procedures for reduction and fixation have been

  10. Clinical Outcome Scoring of Intra-articular Calcaneal Fractures

    NARCIS (Netherlands)

    T. Schepers (Tim); M.J. Heetveld (Martin); P.G.H. Mulder (Paul); P. Patka (Peter)

    2008-01-01

    textabstractOutcome reporting of intra-articular calcaneal fractures is inconsistent. This study aimed to identify the most cited outcome scores in the literature and to analyze their reliability and validity. A systematic literature search identified 34 different outcome scores. The most cited

  11. Subtalar versus triple arthrodesis after intra-articular calcaneal fractures

    NARCIS (Netherlands)

    T. Schepers (Tim); B.C.T. Kieboom (Brenda); J.H.J.M. Bessems (Gert); L.M.M. Vogels (Lucas); E.M.M. van Lieshout (Esther); P. Patka (Peter)

    2010-01-01

    textabstractDepending upon initial treatment, between 2 and 30% of patients with a displaced intra-articular calcaneal fracture require a secondary arthrodesis. The aim of this study was to investigate the effect of subtalar versus triple arthrodesis on functional outcome. A total of 33 patients

  12. Surgery for extra-articular trismus : a systematic review

    NARCIS (Netherlands)

    Bouman, M A; Dijkstra, P U; Reintsema, H; Roodenburg, J L N; Werker, P M N

    2015-01-01

    The aim of this systematic review was to identify operations that are used to improve mouth opening in patients with extra-articular trismus (caused by cancer and its treatment, oral submucous fibrosis, or noma) and to find out if they work. We searched the electronic databases PubMed, Embase, Cinah

  13. Surgery for extra-articular trismus : a systematic review

    NARCIS (Netherlands)

    Bouman, M. A.; Dijkstra, P. U.; Reintsema, H.; Roodenburg, J. L. N.; Werkera, P. M. N.

    2016-01-01

    The aim of this systematic review was to identify operations that are used to improve mouth opening in patients with extra-articular trismus (caused by cancer and its treatment, oral submucous fibrosis, or noma) and to find out if they work. We searched the electronic databases PubMed, Embase, Cinah

  14. Evidence for a negative Pasteur effect in articular cartilage.

    Science.gov (United States)

    Lee, R B; Urban, J P

    1997-01-01

    Uptake of external glucose and production of lactate were measured in freshly-excised bovine articular cartilage under O2 concentrations ranging from 21% (air) to zero (N2-bubbled). Anoxia (O2 concentration Pasteur effect in bovine articular cartilage. Anoxia also suppressed glycolysis in articular cartilage from horse, pig and sheep. Inhibitors acting on the glycolytic pathway (2-deoxy-D-glucose, iodoacetamide or fluoride) strongly decreased aerobic lactate production and ATP concentration, consistent with the belief that articular cartilage obtains its principal supply of ATP from substrate-level phosphorylation in glycolysis. Azide or cyanide lowered the ATP concentration in aerobic cartilage to approximately the same extent as did anoxia but, because glycolysis (lactate production) was also inhibited by these treatments, the importance of any mitochondrial ATP production could not be assessed. A negative Pasteur effect would make chondrocytes particularly liable to suffer a shortage of energy under anoxic conditions. Incorporation of [35S]sulphate into proteoglycan was severely curtailed by treatments, such as anoxia, which decreased the intracellular concentration of ATP.

  15. Doxycycline inhibits collagen synthesis by differentiated articular chondrocytes.

    NARCIS (Netherlands)

    TeKoppele, J.M.; Beekman, B.; Verzijl, N.; Koopman, J.L.; Groot, J. de; Bank, R.A.

    1998-01-01

    Doxycycline (DOX) profoundly inhibited collagen synthesis by differentiated articular chondrocytes. At 25 microM, the rate of collagen synthesis was suppressed by more than 50% without affecting cell proliferation (DNA levels) and general protein synthesis (35S-Met and 35S-Cys incorporation). Steady

  16. A cell-free scaffold-based cartilage repair provides improved function hyaline-like repair at one year.

    Science.gov (United States)

    Siclari, Alberto; Mascaro, Gennaro; Gentili, Chiara; Cancedda, Ranieri; Boux, Eugenio

    2012-03-01

    Bone marrow stimulation techniques in cartilage repair such as drilling are limited by the formation of fibrous to hyaline-like repair tissue. It has been suggested such techniques can be enhanced by covering the defect with scaffolds. We present an innovative approach using a polyglycolic acid (PGA)-hyaluronan scaffold with platelet-rich-plasma (PRP) in drilling. We asked whether (1) PRP immersed in a cell-free PGA-hyaluronan scaffold improves patient-reported 1-year outcomes for the Knee injury and Osteoarthritis Score (KOOS), and (2) implantation of the scaffold in combination with bone marrow stimulation leads to the formation of hyaline-like cartilage repair tissue. We reviewed 52 patients who had arthroscopic implantation of the PGA-hyaluronan scaffold immersed with PRP in articular cartilage defects of the knee pretreated with Pridie drilling. Patients were assessed by KOOS. At 9 months followup, histologic staining was performed in specimens obtained from five patients to assess the repair tissue quality. The KOOS subscores improved for pain (55 to 91), symptoms (57 to 88), activities of daily living (69 to 86), sports and recreation (36 to 70), and quality of life (38 to 73). The histologic evaluation showed a homogeneous hyaline-like cartilage repair tissue. The cell-free PGA-hyaluronan scaffold combined with PRP leads to cartilage repair and improved patient-reported outcomes (KOOS) during 12 months of followup. Histologic sections showed morphologic features of hyaline-like repair tissue. Long-term followup is needed to determine if the cartilage repair tissue is durable. Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

  17. Repair bond strength of resin composite to a novel CAD/CAM hybrid ceramic using different repair systems.

    Science.gov (United States)

    Elsaka, Shaymaa E

    2015-01-01

    This study evaluated the repair bond strength of a nanohybrid resin composite to a novel CAD/CAM hybrid ceramic based on four intraoral ceramic repair systems. Vita Enamic (VE) CAD/CAM hybrid ceramic was used in this study. Specimens were divided into five test groups according to the repair method performed on the ceramic surface: Gr C (No treatment; control); Gr CZ (Cimara Zircon); Gr PR (Porcelain Repair); Gr CR (Clearfil Repair); and Gr CS (CoJet system). Nanohybrid resin composite (GrandioSO) was packed onto treated ceramic surfaces for adhesion testing using microtensile bond strength test. Debonded specimens were examined with a stereomicroscope and SEM to determine the fracture mode. Data were analyzed using ANOVA and Tukey's HSD test. PR and CZ repair systems significantly enhanced the bond strength of nanohybrid resin composite to VE CAD/CAM hybrid ceramic when compared with the other tested repair systems.

  18. Evolution of Autologous Chondrocyte Repair and Comparison to Other Cartilage Repair Techniques

    Directory of Open Access Journals (Sweden)

    Ashvin K. Dewan

    2014-01-01

    Full Text Available Articular cartilage defects have been addressed using microfracture, abrasion chondroplasty, or osteochondral grafting, but these strategies do not generate tissue that adequately recapitulates native cartilage. During the past 25 years, promising new strategies using assorted scaffolds and cell sources to induce chondrocyte expansion have emerged. We reviewed the evolution of autologous chondrocyte implantation and compared it to other cartilage repair techniques. Methods. We searched PubMed from 1949 to 2014 for the keywords “autologous chondrocyte implantation” (ACI and “cartilage repair” in clinical trials, meta-analyses, and review articles. We analyzed these articles, their bibliographies, our experience, and cartilage regeneration textbooks. Results. Microfracture, abrasion chondroplasty, osteochondral grafting, ACI, and autologous matrix-induced chondrogenesis are distinguishable by cell source (including chondrocytes and stem cells and associated scaffolds (natural or synthetic, hydrogels or membranes. ACI seems to be as good as, if not better than, microfracture for repairing large chondral defects in a young patient’s knee as evaluated by multiple clinical indices and the quality of regenerated tissue. Conclusion. Although there is not enough evidence to determine the best repair technique, ACI is the most established cell-based treatment for full-thickness chondral defects in young patients.

  19. Induction of spontaneous hyaline cartilage regeneration using a double-network gel: efficacy of a novel therapeutic strategy for an articular cartilage defect.

    Science.gov (United States)

    Kitamura, Nobuto; Yasuda, Kazunori; Ogawa, Munehiro; Arakaki, Kazunobu; Kai, Shuken; Onodera, Shin; Kurokawa, Takayuki; Gong, Jian Ping

    2011-06-01

    A double-network (DN) gel, which was composed of poly-(2-acrylamido-2-methylpropanesulfonic acid) and poly-(N,N'-dimetyl acrylamide) (PAMPS/PDMAAm), has the potential to induce chondrogenesis both in vitro and in vivo. To establish the efficacy of a therapeutic strategy for an articular cartilage defect using a DN gel. Controlled laboratory study. A 4.3-mm-diameter osteochondral defect was created in rabbit trochlea. A DN gel plug was implanted into the defect of the right knee so that a defect 2 mm in depth remained after surgery. An untreated defect of the left knee provided control data. The osteochondral defects created were examined by histological and immunohistochemical evaluations, surface assessment using confocal laser scanning microscopy, and real-time polymerase chain reaction (PCR) analysis at 4 and 12 weeks. Samples were quantitatively evaluated with 2 scoring systems reported by Wayne et al and O'Driscoll et al. The DN gel-implanted defect was filled with a sufficient volume of the hyaline cartilage tissue rich in proteoglycan and type 2 collagen. Quantitative evaluation using the grading scales revealed a significantly higher score in the DN gel-implanted defects compared with the untreated control at each period (P cartilage at 12 weeks (P = .0106), while there was no statistical difference between the DN gel-implanted and normal knees. This study using the mature rabbit femoral trochlea osteochondral defect model demonstrated that DN gel implantation is an effective treatment to induce cartilage regeneration in vivo without any cultured cells or mammalian-derived scaffolds. This study has prompted us to develop a potential innovative strategy to repair cartilage lesions in the field of joint surgery.

  20. The Effectiveness of Ultrasound-Guided Steroid Injection for Femoroacetabular Impingement: A Comparison between the Extra-Articular and Intra-Articular Approaches

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Chang Ho; Lee, Joon Woo [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2013-03-15

    To assess the effectiveness of pain control using ultrasound-guided steroid injection by the extra-articular and intra-articular approaches to femoroacetabular impingement patients. From September through December 2010, 18 patients with clinical suspicion of femoroacetabular impingement syndrome underwent ultrasound-guided steroid and local anesthetics injection: a total of 20 cases, including 16 cases of ipsilateral and 2 cases of bilateral injection. Extra-articular or intra-articular approach was selected for each patient, randomly and alternately. Nine cases were performed by extra-articular approach and 11 cases were performed by intra-articular approach. Every patient was observed in the outpatient clinic and visual analogue scale (VAS) was taken and compared before and after the procedure in all patients. Pre-injection average VAS value of extra-articular approached cases was 5.22 {+-} 1.99 and post-injection average VAS value was 4.11 {+-} 1.96, which is statistically insignificant (p < 0.156). The average VAS value of intra-articular approached cases was decreased from 5.72 {+-} 2.15 to 2.91 {+-} 2.30 after injection, which is statistically significant (p < 0.006). Ultrasound guided intra-articular approached steroid and local anesthetics injection could be effective in controlling pain for patients with femoroacetabular impingement syndrome.

  1. Effect of highly purified capsaicin on articular cartilage and rotator cuff tendon healing: An in vivo rabbit study.

    Science.gov (United States)

    Friel, Nicole A; McNickle, Allison G; DeFranco, Michael J; Wang, FanChia; Shewman, Elizabeth F; Verma, Nikhil N; Cole, Brian J; Bach, Bernard R; Chubinskaya, Susan; Kramer, Susan M; Wang, Vincent M

    2015-12-01

    Highly purified capsaicin has emerged as a promising injectable compound capable of providing sustained pain relief following a single localized treatment during orthopedic surgical procedures. To further assess its reliability for clinical use, the potential effect of highly purified capsaicin on articular cartilage metabolism as well as tendon structure and function warrants clarification. In the current study, rabbits received unilateral supraspinatus transection and repair with a single 1 ml injection of capsaicin (R+C), PEG-only placebo (R+P), or saline (R+S) into the glenohumeral joint (GHJ). An additional group received 1 ml capsaicin onto an intact rotator cuff (I+C). At 18 weeks post-op, cartilage proteoglycan (PG) synthesis and content as well as cell viability were similar (p>0.05) across treatment groups. Biomechanical testing revealed no differences (p>0.05) among tendon repair treatment groups. Similarly, histologic features of both cartilage and repaired tendons showed minimal differences across groups. Hence, in this rabbit model, a single injection of highly purified capsaicin into the GHJ does not induce a deleterious response with regard to cartilage matrix metabolism and cell viability, or rotator cuff healing. These data provide further evidence supporting the use of injectable, highly purified capsaicin as a safe alternative for management of postoperative pain following GHJ surgery.

  2. Sarcoma sinovial extra-articular em cão Extra-articular synovial sarcoma in a dog

    Directory of Open Access Journals (Sweden)

    S.A. França

    2004-10-01

    Full Text Available One four-year-old, female, Collie, dog presented subcutaneous enlarged mass at the lateral aspect of the left hindlimb, close to the knee joint. Based on the anatomopathological and immunohistochemical findings it was confirmed the diagnosis of extra-articular bifasic synovial sarcoma - grade II.

  3. Percutaneous mitral valve repair.

    Science.gov (United States)

    Gillinov, A Marc; Liddicoat, John R

    2006-01-01

    Surgical mitral valve repair is the procedure of choice to treat mitral regurgitation of all etiologies. Whereas annuloplasty is the cornerstone of mitral valve repair, a variety of other surgical techniques are utilized to correct dysfunction of the leaflets and subvalvular apparatus; in most cases, surgical repair entails application of multiple repair techniques in each patient. Preclinical studies and early human experience have demonstrated that some of these surgical repair techniques can be performed using percutaneous approaches. Specifically, there has been great progress in the development of novel technology to facilitate percutaneous annuloplasty and percutaneous edge-to-edge repair. The objectives of this report were to (1) discuss the surgical foundations for these percutaneous approaches; (2) review device design and experimental and clinical results of percutaneous valve repair; and (3) address future directions, including the key challenges of patient selection and clinical trial design.

  4. Cartilage repair: Generations of autologous chondrocyte transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Marlovits, Stefan [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)]. E-mail: stefan.marlovits@meduniwien.ac.at; Zeller, Philip [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Singer, Philipp [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Resinger, Christoph [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Vecsei, Vilmos [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2006-01-15

    Articular cartilage in adults has a limited capacity for self-repair after a substantial injury. Surgical therapeutic efforts to treat cartilage defects have focused on delivering new cells capable of chondrogenesis into the lesions. Autologous chondrocyte transplantation (ACT) is an advanced cell-based orthobiologic technology used for the treatment of chondral defects of the knee that has been in clinical use since 1987 and has been performed on 12,000 patients internationally. With ACT, good to excellent clinical results are seen in isolated post-traumatic lesions of the knee joint in the younger patient, with the formation of hyaline or hyaline-like repair tissue. In the classic ACT technique, chondrocytes are isolated from small slices of cartilage harvested arthroscopically from a minor weight-bearing area of the injured knee. The extracellular matrix is removed by enzymatic digestion, and the cells are then expanded in monolayer culture. Once a sufficient number of cells has been obtained, the chondrocytes are implanted into the cartilage defect, using a periosteal patch over the defect as a method of cell containment. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. Further improvements in tissue engineering have contributed to the next generation of ACT techniques, where cells are combined with resorbable biomaterials, as in matrix-associated autologous chondrocyte transplantation (MACT). These biomaterials secure the cells in the defect area and enhance their proliferation and differentiation.

  5. Partial restoration of immobilization-induced softening of canine articular cartilage after remobilization of the knee (stifle) joint.

    Science.gov (United States)

    Jurvelin, J; Kiviranta, I; Säämänen, A M; Tammi, M; Helminen, H J

    1989-01-01

    The restoration of the biomechanical properties of articular cartilage was studied after 15 weeks of remobilization of the knee joint in beagles previously immobilized with a cast for 11 weeks. The shear moduli were determined with an indentation creep test immediately after load application and at equilibrium at six predefined test points of femoral, tibial, and patellar cartilages. Permeability of the cartilage was estimated from the creep measurements. The values were compared with nontreated, age-matched (55 weeks) controls and with cartilage collected immediately after immobilization. Remobilization reduced the high creep rates created by immobilization and shifted the depressed equilibrium shear moduli towards those of the controls. However, in the femoral condylar cartilage, the equilibrium shear modulus remained at lower level (p less than 0.05) and permeability at higher level (p less than 0.05) as compared with the controls. We conclude that articular cartilage, showing signs of atrophy after long-term immobilization, was capable of restoring its biomechanical properties during remobilization. This repair was not, however, completed in all parts of the knee joint by the end of the observation period.

  6. Coralline hydroxyapatite is a suitable bone graft substitute in an intra-articular goat defect model.

    Science.gov (United States)

    Koëter, S; Tigchelaar, S J; Farla, P; Driessen, L; van Kampen, A; Buma, P

    2009-07-01

    Intra-articular defects can be filled with an autologous bone graft taken from the iliac crest. This can be indicated after trauma or following correcting osteotomy. Patients may encounter donor site morbidity after this procedure. In this in vivo study, we studied if coralline hydroxyapatite (CHA) is a suitable material to replace autologous bone graft to fill a defect in the femoral trochlea of goats. CHA did not evoke any negative reaction in the synovium, and the articular cartilage was comparable to controls. In the bone graft group, we found scattered areas of (enchondral formed) bone. Most bone graft had been resorbed or remodeled, and the scarce remnants were incorporated into new bone. Resorption of CHA was limited or absent and most CHA was surrounded by new bone. In areas with fragmented CHA, close to the joint surface, numerous giant cells were found. The study shows that in this animal model, CHA inserted in a defect that directly communicates with the joint space incorporates into bone. This study did not show any negative effects of CHA in a joint environment.

  7. Deginerative changes of femoral articular cartilage in the knee : comparative study of specimen sonography and pathology

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ju Youn; Hong, Sung Hwan; Sohn, Jin Hee; Wee, Young Hoon; Chang, Jun Dong; Park, Hong Seok; Lee, Eil Seoung; Kang Ik Won [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

    2001-04-01

    To determine the sonographic findings of degenerative change in femoral articular cartilage of the knee by comparative study of specimen sonography and pathology. We obtained 40 specimens of cartilage of the femur (20 medial and 20 lateral condylar) from 20 patients with osteoarthritis of the knee who had undergone total knee replacement. The specimens were placed in a saline-filled container and sonography was performed using a 10-MHz linear transducer. Sonographic abnormalities were evaluated at the cartilage surface, within the cartilage, and at the bone-cartilage interface, and were compared with the corresponding pathologic findings. In addition, cartilage thickness was measured at a representative portion of each femoral cartilage specimen and was compared with the thickness determined by sonography. 'Dot' lesions, irregularity or loss of the hyperechoic line, were demonstrated by sonography at the saline-cartilage interface of 14 cartilages. Pathologic examination showed that these findings corresponded to cleft, detachment, erosion, and degeneration. Irregularities in the hyperechoic line at the bone-cartilage interface were revealed by sonography in eight cartilages and were related to irregularity or loss of tidemark, downward displacement of the cartilage, and subchondral callus formation. Dot lesions, corresponding to cleft and degeneration, were noted within one cartilage. Cartilage thickness measured on specimen and by sonography showed no significant difference (p=0.446). Specimen sonography suggested that articular cartilage underwent degenerative histopathological change. Cartilage thickness measured by sonography exactly reflected real thickness.

  8. 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.

  9. In-laboratory diffraction-enhanced X-ray imaging for articular cartilage.

    Science.gov (United States)

    Muehleman, Carol; Fogarty, Daniel; Reinhart, Benjamin; Tzvetkov, Tochko; Li, Jun; Nesch, Ivan

    2010-07-01

    The loss of articular cartilage characteristic of osteoarthritis can only be diagnosed by joint space narrowing when conventional radiography is used. This is due to the lack of X-ray contrast of soft tissues. Whereas conventional radiography harnesses the X-ray attenuation properties of tissues, Diffraction Enhanced Imaging (DEI), a novel radiographic technique, allows the visualization of soft tissues simultaneous with calcified tissues by virtue of its ability to not only harness X-ray attenuation but also the X-ray refraction from tissue boundaries. Previously, DEI was dependent upon synchrotron X-rays, but more recently, the development of nonsynchrotron DEI units has been explored. These developments serve to elaborate the full potential of radiography. Here, we tested the potential of an in-laboratory DEI system, called Diffraction-Enhanced X-ray Imaging (DEXI), to render images of articular cartilage displaying varying degrees of degradation, ex vivo. DEXI allowed visualization of even early stages of cartilage degeneration such as surface fibrillation. This may be of eventual clinical significance for the diagnosis of early stages of degeneration, or at the very least, to visualize soft tissue degeneration simultaneous with bone changes.

  10. Incomplete restoration of immobilization induced softening of young beagle knee articular cartilage after 50-week remobilization.

    Science.gov (United States)

    Haapala, J; Arokoski, J; Pirttimäki, J; Lyyra, T; Jurvelin, J; Tammi, M; Helminen, H J; Kiviranta, I

    2000-01-01

    The aim of this study was to characterize the biomechanical and structural changes in canine knee cartilage after an initial 11-week immobilization and subsequent remobilization period of 50 weeks. Cartilage from the immobilized and remobilized knee was compared with the tissue from age-matched control animals. Compressive stiffness, in the form of instant shear modulus (ISM) and equilibrium shear modulus (ESM) of articular cartilage, was investigated using an in situ indentation creep technique. The local variations in cartilage of glycosaminoglycan (GAG) concentration were measured with a microspectrophotometer after safranin O staining of histological sections. Using a computer-based quantitative polarized light microscopy method, collagen-related optical retardation, gamma, of cartilage zones were performed to investigate the collagen network of cartilage. Macroscopically, cartilage surfaces of the knee joint remained intact both after immobilization and remobilization periods. Immobilization caused significant softening of the lateral femoral and tibial cartilages, as expressed by ESM (up to 30%, p test points. The changes of ESM were positively correlated with the alterations in GAG content of the superficial and deep zones after immobilization and remobilization. This confirms the key role of protoglycans in the regulation of the equilibrium stiffness of articular cartilage. As a conclusion, immobilization of the joint of a young individual may cause long-term, if not permanent, alterations of cartilage biomechanical properties. This may predispose joint to degenerative changes later in life.

  11. Poly(dopamine) coating of scaffolds for articular cartilage tissue engineering.

    Science.gov (United States)

    Tsai, Wei-Bor; Chen, Wen-Tung; Chien, Hsiu-Wen; Kuo, Wei-Hsuan; Wang, Meng-Jiy

    2011-12-01

    A surface modification technique based on poly(dopamine) deposition developed from oxidative polymerization of dopamine is known to promote cell adhesion to several cell-resistant substrates. In this study this technique was applied to articular cartilage tissue engineering. The adhesion and proliferation of rabbit chondrocytes were evaluated on poly(dopamine)-coated polymer films, such as polycaprolactone, poly(L-lactide), poly(lactic-co-glycolic acid) and polyurethane, biodegradable polymers that are commonly used in tissue engineering. Cell adhesion was significantly increased by merely 15 s of dopamine incubation, and 4 min incubation was enough to reach maximal cell adhesion, a 1.35-2.69-fold increase compared with that on the untreated substrates. Cells also grew much faster on the poly(dopamine)-coated substrates than on untreated substrates. The increase in cell affinity for poly(dopamine)-coated substrates was demonstrated via enhancement of the immobilization of serum adhesive proteins such as fibronectin. When the poly(dopamine)-coating technique was applied to three-dimensional (3-D) polyurethane scaffolds, the proliferation of chondrocytes and the secretion of glycosaminoglycans were increased compared with untreated scaffolds. Our results show that the deposition of a poly(dopamine) layer on 3-D porous scaffolds is a simple and promising strategy for articular cartilage tissue engineering, and may be applied to other types of tissue engineering.

  12. Proteoglycan concentrations in healthy and diseased articular cartilage by Fourier transform infrared imaging and principal component regression

    Science.gov (United States)

    Yin, Jianhua; Xia, Yang

    2014-12-01

    Fourier transform infrared imaging (FTIRI) combining with principal component regression (PCR) analysis were used to determine the reduction of proteoglycan (PG) in articular cartilage after the transection of the anterior cruciate ligament (ACL). A number of canine knee cartilage sections were harvested from the meniscus-covered and meniscus-uncovered medial tibial locations from the control joints, the ACL joints at three time points after the surgery, and their contralateral joints. The PG loss in the ACL cartilage was related positively to the durations after the surgery. The PG loss in the contralateral knees was less than that of the ACL knees. The PG loss in the meniscus-covered cartilage was less than that of the meniscus-uncovered tissue in both ACL and contralateral knees. The quantitative mapping of PG loss could monitor the disease progression and repair processes in arthritis.

  13. Suppression of adverse angiogenesis in an albumin-based hydrogel for articular cartilage and intervertebral disc regeneration

    Directory of Open Access Journals (Sweden)

    B Scholz

    2010-07-01

    Full Text Available An injectable polyethylene glycol-crosslinked albumin gel (AG supplemented with hyaluronic acid as a matrix for autologous chondrocyte implantation was evaluated with regard to its impact on angiogenesis. Healthy articular cartilage and intervertebral discs (IVD are devoid of blood vessels, whereas pathological blood vessel formation augments degeneration of both theses tissues. In contrast to human endothelial cells, primary human articular chondrocytes encapsulated in the AG retained their viability. Endothelial cells did not adhere to the gel surface to a significant extent nor did they proliferate in vitro. The AG did not release any diffusible toxic components. Contrary to MatrigelTM employed as positive control, the AG prevented endothelial chemoinvasion in Transwell filter assays even in the presence of a chemotactic gradient of vascular endothelial growth factor. In ovo, the AG exhibited a barrier function for blood vessels of the chick chorioallantoic membrane. Subcutaneous implantation of human IVD chondrocytes enclosed in the albumin gel into immunodeficient mice revealed a complete lack of angiogenesis inside the gel after two weeks. At the same time, the IVD chondrocytes within the gel remained vital and displayed a characteristic gene expression pattern as judged from aggrecan, collagen type I and type II mRNA levels. In summary, aiming at articular cartilage and IVD regeneration the albumin gel promises to be a beneficial implant matrix for chondrocytes simultaneously exhibiting non-permissive properties for adverse endothelial cells.

  14. Effect of retaining articular capsule in total hip arthroplasty through posterior approach on hip stability%经后侧入路人工全髋关节置换保留关节囊对关节稳定性的影响

    Institute of Scientific and Technical Information of China (English)

    吴慧敏; 何爱咏

    2008-01-01

    BACKGROUND:Articular capsule ligaments can lead articular surface to move normally and limit the excessive movement, especially to prevent any non-physiological movement. They are the important structures for stabilizing hip joints. It was previously thought that articular capsule should be routinely resected in the total hip arthroplasty (THA). OBJECTIVE: This study was designed to investigate the effect of retaining articular capsule in THA through posterior approach on maintaining hip stability. DESIGN, TIME AND SETTING: This study, a retrospective case analysis, was performed on 61 patients with femoral neck fracture, who received treatment in the Department of Orthopedics, Xiangya Second Hospital of Central South between January 2005 and December 2006. PARTICIPANTS: Twenty-nine patients who underwent THA with retaining articular capsule from January to December 2006 were included as retaining group, and thirty-two patients who underwent THA with routine resection of partial articular capsule were included as routine group. The two groups were kept identical in case selection, prosthesis selection, post-surgery processing and operators. METHODS: Four holes were drilled on greater trochanter on the proximal femoral bone. The superior part of articular capsule valve was sutured to the superior part of original articular capsule using No.1-0 absorbing thread, then sutured to base of femoral neck in mattress manner, and the suture was not ligated. The inferior part of articular capsule valve was sutured to the inferior part of original articular capsule using another suture. And the suture passed through two bone holes on base of femoral neck. The lower limbs were externally rotated and the suture was ligated. Subsequently, the excised extortor was repaired. Prior to and subsequent to suture, hip was slowly bent for 90° and femur was internally rotated for45°to investigate the suture of articular capsule on strengthening articular stability. MAI OUTCOME MEASURES

  15. Repair of rabbit cartilage defect based on the fusion of rabbit bone marrow stromal cells and Nano-HA/PLLA composite material.

    Science.gov (United States)

    Zhu, Weimin; Guo, Daiqi; Peng, Liangquan; Chen, Yun Fang; Cui, Jiaming; Xiong, Jianyi; Lu, Wei; Duan, Li; Chen, Kang; Zeng, Yanjun; Wang, Daping

    2017-02-01

    Objective To assess the effect of the fusion of rabbit bone marrow stromal cells (rBMSCs) and Nano-hydroxyapatite/poly (l-lactic acid) (Nano-HA/PLLA) in repairing the rabbit knee joint with full-thickness cartilage defect. Method The rBMSCs were isolated and cultured in vitro, and the third generation of rBMSCs was co-cultured with the Nano-HA/PLLA to construct the tissue-engineered cartilage (TEC). Eighteen New Zealand white rabbits were selected and randomly divided into three groups, namely, TEC group, Nano-HA/PLLA group, and control group. A cartilage defect model with the diameter of 4.5 mm and depth of 5 mm was constructed on the articular surface of medial malleolus of rabbit femur. General observation, histological observation, and Wakitani's histological scoring were conducted in the 12th and 24th week postoperatively. Results The results of TEC group indicated that new cartilage tissue was formed on the defect site and subchondral bone achieved physiological integration basically. Histological and immunohistochemical analyses indicated the generation of massive extracellular matrix. In contrast, limited regeneration and reconstruction of cartilage was achieved in the Nano-HA/PLLA group and control group, with a significant difference from the TEC group (p Nano-HA/PLLA combined with BMSCs promoted the repair of weight-bearing bone of adult rabbit's knee joint with cartilage defect.

  16. Nanofibrous poly(3-hydroxybutyrate)/poly(3-hydroxyoctanoate) scaffolds provide a functional microenvironment for cartilage repair.

    Science.gov (United States)

    Ching, Kuan Y; Andriotis, Orestis G; Li, Siwei; Basnett, Pooja; Su, Bo; Roy, Ipsita; Tare, Rahul S; Sengers, Bram G; Stolz, Martin

    2016-07-01

    Articular cartilage defects, when repaired ineffectively, often lead to further deterioration of the tissue, secondary osteoarthritis and, ultimately, joint replacement. Unfortunately, current surgical procedures are unable to restore normal cartilage function. Tissue engineering of cartilage provides promising strategies for the regeneration of damaged articular cartilage. As yet, there are still significant challenges that need to be overcome to match the long-term mechanical stability and durability of native cartilage. Using electrospinning of different blends of biodegradable poly(3-hydroxybutyrate)/poly(3-hydroxyoctanoate), we produced polymer scaffolds and optimised their structure, stiffness, degradation rates and biocompatibility. Scaffolds with a poly(3-hydroxybutyrate)/poly(3-hydroxyoctanoate) ratio of 1:0.25 exhibit randomly oriented fibres that closely mimic the collagen fibrillar meshwork of native cartilage and match the stiffness of native articular cartilage. Degradation of the scaffolds into products that could be easily removed from the body was indicated by changes in fibre structure, loss of molecular weight and a decrease in scaffold stiffness after one and four months. Histological and immunohistochemical analysis after three weeks of culture with human articular chondrocytes revealed a hyaline-like cartilage matrix. The ability to fine tune the ultrastructure and mechanical properties using different blends of poly(3-hydroxybutyrate)/poly(3-hydroxyoctanoate) allows to produce a cartilage repair kit for clinical use to reduce the risk of developing secondary osteoarthritis. We further suggest the development of a toolbox with tailor-made scaffolds for the repair of other tissues that require a 'guiding' structure to support the body's self-healing process.

  17. Optimality in DNA repair.

    Science.gov (United States)

    Richard, Morgiane; Fryett, Matthew; Miller, Samantha; Booth, Ian; Grebogi, Celso; Moura, Alessandro

    2012-01-07

    DNA within cells is subject to damage from various sources. Organisms have evolved a number of mechanisms to repair DNA damage. The activity of repair enzymes carries its own risk, however, because the repair of two nearby lesions may lead to the breakup of DNA and result in cell death. We propose a mathematical theory of the damage and repair process in the important scenario where lesions are caused in bursts. We use this model to show that there is an optimum level of repair enzymes within cells which optimises the cell's response to damage. This optimal level is explained as the best trade-off between fast repair and a low probability of causing double-stranded breaks. We derive our results analytically and test them using stochastic simulations, and compare our predictions with current biological knowledge.

  18. One intra-articular injection of hyaluronan prevents cell death and improves cell metabolism in a model of injured articular cartilage in the rabbit

    NARCIS (Netherlands)

    Jansen, Edwin J. P.; Ernans, Pieter J.; Douw, Conny M.; Guidemond, Nick A.; Van Rhijn, Lodewijk W.; Bulstra, Sjoerd K.; Kuijer, Roell

    2008-01-01

    The purpose of this study was to determine the effect of one intra-articular injection of hyaluronan on chondrocyte death and metabolism in injured cartilage. Twenty-three 6-month-old rabbits received partial-thickness articular cartilage defects created on each medial femoral condyle. In order to e

  19. Epidemiology of extra-articular manifestations in rheumatoid arthritis.

    Science.gov (United States)

    Turesson, C; Jacobsson, L T H

    2004-01-01

    Extra-articular RA (ExRA) includes a wide variety of disease manifestations. Although rheumatologists in general are aware that such events are clinically important, the heterogeneity of available data, including discrepancies in case definitions, has complicated constructive discussions on this aspect of the RA disease phenotype. In recent years, there has been a growing recognition of the importance of co-morbidity in patients with RA. ExRA manifestations are not uncommon, explain excess mortality in RA and are predicted by smoking and autoantibodies. Further studies of the mechanisms underlying these associations are likely to be important in improving our understanding of the systemic nature of RA. This article discusses the methodological issues involved in the study of ExRA manifestations, presents suggested criteria that have been used in clinical studies, and reviews important surveys of the epidemiology of extra-articular RA.

  20. Autologous chondrocyte transplantation for the treatment of articular cartilage defects in the knee joint. Techniques and results; Autologe Chondrozytentransplantation zur Behandlung von Knorpeldefekten des Kniegelenks. Techniken und Ergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Marlovits, S.; Kutscha-Lissberg, F.; Aldrian, S.; Resinger, C.; Singer, P.; Zeller, P.; Vecsei, V. [Universitaetsklinik fuer Unfallchirurgie, Medizinische Universitaet Wien (Austria)

    2004-08-01

    Currently the use of autologous chondrocytes as a cartilage-repair procedure for the repair of injured articular cartilage of the knee joint, is recommended. This review presents the technique of autologous chondrocyte transplantation (ACT) and their modifications as matrix-associated autologous chondrocyte transplantation (MACT). Beside the surgical procedure the experimental and clinical results are discussed. Furthermore the major complications and the indication guidelines are presented. Articular cartilage in adults has a poor ability to self-repair after a substantial injury. Surgical therapeutic efforts in treating cartilage defects have focused on bringing new cells capable of chondrogenesis into the lesions. With ACT good to excellent clinical results are seen in isolated posttraumatic lesions of the knee joint in the younger patient with the formation of hyalinelike repair tissue. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. The current limitations include osteoarthritic defects and higher patient age. With the right indication and operative technique ACT is an effective and save option for the treatment of large full thickness cartilage defect of the knee joint. (orig.) [German] Zur Behandlung umschriebener Defekte des artikulaeren Kniegelenkgelenkknorpels wird der Einsatz autologer Knorpelzellen zunehmend als neue biologische Methode empfohlen. Die Technik der autologen Chondrozytentransplantation (ACT) und deren Modifikationen als matrixassoziierte autologe Chondrozytentransplantation (MACT) werden dargestellt. Es erfolgt ein Ueberblick ueber die experimentellen und klinischen Ergebnisse mit der Darstellung der haeufigsten Komplikationen und den derzeit gueltigen Indikationsrichtlinien. Unter Verwendung qualitativ hochwertiger Zellen zeigen besonders posttraumatische Knorpeldefekte bei juengeren Patienten eine hohe Erfolgsquote mit der Ausbildung eines hyalinartigen