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Sample records for proximal femur geometric

  1. The shape of the hominoid proximal femur: a geometric morphometric analysis

    Science.gov (United States)

    Harmon, Elizabeth H

    2007-01-01

    As part of the hip joint, the proximal femur is an integral locomotor component. Although a link between locomotion and the morphology of some aspects of the proximal femur has been identified, inclusive shapes of this element have not been compared among behaviourally heterogeneous hominoids. Previous analyses have partitioned complex proximal femoral morphology into discrete features (e.g. head, neck, greater trochanter) to facilitate conventional linear measurements. In this study, three-dimensional geometric morphometrics are used to examine the shape of the proximal femur in hominoids to determine whether femoral shape co-varies with locomotor category. Fourteen landmarks are recorded on adult femora of Homo, Pan, Gorilla, Pongo and Hylobates. Generalized Procrustes analysis (GPA) is used to adjust for position, orientation and scale among landmark configurations. Principal components analysis is used to collapse and compare variation in residuals from GPA, and thin-plate spline analysis is used to visualize shape change among taxa. The results indicate that knucklewalking African apes are similar to one another in femoral shape, whereas the more suspensory Asian apes diverge from the African ape pattern. The shape of the human and orangutan proximal femur converge, a result that is best explained in terms of the distinct requirements for locomotion in each group. These findings suggest that the shape of the proximal femur is brought about primarily by locomotor behaviour. PMID:17310545

  2. Proximal femur geometry in the adult Kenyan femur and its ...

    African Journals Online (AJOL)

    Background: Numerous orthopaedic procedures are carried out on the proximal femur. For optimal hip function, these procedures must restore the anatomy of the proximal femur to as near normal as possible. There are currently no local studies that have described in detail the normal anatomy of the proximal femur and its ...

  3. proximal femur geometry in the adult kenyan femur and its ...

    African Journals Online (AJOL)

    implications considering that the implants used to treat fractures in the proximal femur would usually traverse the neck and lodge in the femoral head. A very narrow neck may not allow adequate implant placement especially for those implants that employ two proximal locking screws. This has been shown, in a study by ...

  4. Automated Acquisition of Proximal Femur Morphological Characteristics

    Science.gov (United States)

    Tabakovic, Slobodan; Zeljkovic, Milan; Milojevic, Zoran

    2014-10-01

    The success of the hip arthroplasty surgery largely depends on the endoprosthesis adjustment to the patient's femur. This implies that the position of the femoral bone in relation to the pelvis is preserved and that the endoprosthesis position ensures its longevity. Dimensions and body shape of the hip joint endoprosthesis and its position after the surgery depend on a number of geometrical parameters of the patient's femur. One of the most suitable methods for determination of these parameters involves 3D reconstruction of femur, based on diagnostic images, and subsequent determination of the required geometric parameters. In this paper, software for automated determination of geometric parameters of the femur is presented. Detailed software development procedure for the purpose of faster and more efficient design of the hip endoprosthesis that ensures patients' specific requirements is also offered

  5. Dedifferentiated chondrosarcoma of right proximal femur

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    Sachin A Badge

    2016-01-01

    Full Text Available Dedifferentiated chondrosarcoma (DDCS comprises approximately 10% of all chondrosarcomas. The tumor generally occurs after the age of 50 years, with equal distribution among males and females. It is most often located in the bones of the pelvis, the proximal femur or humerus, the distal femur, and the ribs. Regardless of treatment, the prognosis is ominous with 90% of patients dying with distant metastases within 2 years. We report a case of DDCS of right proximal femur in a 73-year-old woman. The most important factors affecting survival are early recognition of the radiographic features, adequate histological sampling, and wide-margin resection of the lesion. So for the correct histopathological diagnosis the biopsy sample should be adequate to visualize both cartilaginous and noncartilaginous sarcomatous component which helps to increase the survival of patients before the distant metastasis occurs.

  6. Adolescent physical activity and bone strength at the proximal femur in adulthood.

    Science.gov (United States)

    Jackowski, Stefan A; Kontulainen, Saija A; Cooper, David M L; Lanovaz, Joel L; Beck, Thomas J; Baxter-Jones, Adam D G

    2014-04-01

    Physical activity (PA) enhances bone structural strength at the proximal femur in adolescence, but whether these benefits are maintained into early adulthood remains unknown. The purpose of this study was to investigate whether males and females, described as active, average, and inactive during adolescence, display differences in structural strength at the proximal femur in early adulthood (20-30 yr). One hundred four participants (55 males and 49 females) from the Pediatric Bone Mineral Accrual Study (PBMAS) were categorized into adolescent PA groupings (inactive, average, and active) using the Physical Activity Questionnaire for Adolescents. Cross-sectional area and section modulus (Z) at the narrow neck, intertrochanter, and femoral shaft (S) sites of the proximal femur were assessed using hip structural analysis in young adulthood from femoral neck dual-energy x-ray absorptiometry scans. Group differences were assessed using ANCOVA, controlling for adult height (Ht), adult weight (Wt), adolescent bone geometry, sex, percentage adult total body lean tissue (LTM%), and adult PA levels. Active adolescents had significantly greater adjusted bone geometric measures at all sites than their inactive classified peers during adolescence (P femur than adult participants who were classified as inactive during adolescence (P femur in young adulthood.

  7. Osteosynthesis of a periprosthetic fracture of the proximal femur with the distal femur LISS system

    DEFF Research Database (Denmark)

    Tarnowski, Jan Robert; Holck, Kim

    2008-01-01

    In this case report, we show how it is possible to perform osteosynthesis using minimal invasive techniques instead of conventional methods. In this instance the osteosynthesis was performed on a patient in poor general condition who had presented a periprosthetic fracture of the proximal femur. ...

  8. Total hip arthroplasty after failed treatment of proximal femur fracture.

    Science.gov (United States)

    Tetsunaga, Tomonori; Fujiwara, Kazuo; Endo, Hirosuke; Noda, Tomoyuki; Tetsunaga, Tomoko; Sato, Toru; Shiota, Naofumi; Ozaki, Toshifumi

    2017-03-01

    Total hip arthroplasty (THA) is a good option as a salvage procedure after failed treatment of proximal femur fracture. The anatomy of the proximal femur, however, makes this surgery complicated and challenging. The purpose of this study was to evaluate the radiographic and clinical outcomes of THA after failed treatment of proximal femur fractures. We retrospectively analysed 50 consecutive THAs (42 women, 8 men; mean age 77 years) after failed treatment of a proximal femur fracture. Mean postoperative follow-up was 58.1 months. Preoperative diagnoses were femoral neck fracture in 18 hips and trochanteric fracture in 32 hips, including three that were infected. Failure resulted from cutout in 22 cases, osteonecrosis in 12, non-union with failed fixation in nine, postoperative osteoarthritis in four, and infection in three. Factors compared included radiographic assessment, complication rate, visual analogue scale (VAS), and Harris Hip Scores (HHS). Radiographic variables included femoral neck anteversion and cup and stem alignment. Absolute values of the differences in femoral neck anteversion between the affected and healthy sides were 6.0° in the femoral neck fracture group and 19.2° in the trochanteric fracture group (p = 0.01). There were no significant differences in cup anteversion (p = 0.20) or stem anteversion (p = 0.08). The complication rate was significantly higher in the trochanteric fracture group than in the femoral neck fracture group (25 vs 0%, p fracture group included three periprosthetic fractures (9.4%), two dislocations (6.3%), two surgical-site infections (6.3%), and one stem penetration (3.1%). Although no significant differences between groups were seen in the VAS or HHS at final follow-up (p = 0.32, 0.09, respectively), these measures were significantly improved at final follow-up in both groups (p fractures requires consideration of complication risk and incorrect femoral neck anteversion.

  9. A method for sex estimation using the proximal femur.

    Science.gov (United States)

    Curate, Francisco; Coelho, João; Gonçalves, David; Coelho, Catarina; Ferreira, Maria Teresa; Navega, David; Cunha, Eugénia

    2016-09-01

    The assessment of sex is crucial to the establishment of a biological profile of an unidentified skeletal individual. The best methods currently available for the sexual diagnosis of human skeletal remains generally rely on the presence of well-preserved pelvic bones, which is not always the case. Postcranial elements, including the femur, have been used to accurately estimate sex in skeletal remains from forensic and bioarcheological settings. In this study, we present an approach to estimate sex using two measurements (femoral neck width [FNW] and femoral neck axis length [FNAL]) of the proximal femur. FNW and FNAL were obtained in a training sample (114 females and 138 males) from the Luís Lopes Collection (National History Museum of Lisbon). Logistic regression and the C4.5 algorithm were used to develop models to predict sex in unknown individuals. Proposed cross-validated models correctly predicted sex in 82.5-85.7% of the cases. The models were also evaluated in a test sample (96 females and 96 males) from the Coimbra Identified Skeletal Collection (University of Coimbra), resulting in a sex allocation accuracy of 80.1-86.2%. This study supports the relative value of the proximal femur to estimate sex in skeletal remains, especially when other exceedingly dimorphic skeletal elements are not accessible for analysis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Three-Dimensional Bone Adaptation of the Proximal Femur

    DEFF Research Database (Denmark)

    Bagge, Mette

    1998-01-01

    The bone remodeling of a three-dimensional model of the proximal femur is considered. The bone adaptation is numerically described as an evolution in time formulated such that the structural change goes in an optimal direction within each time step for the optimal boundary conditions. In the bone...... remodeling scheme is included the memory of past loadings to account for the delay in the bone response to the load changes. In order to get a realistic bone adaptation process, the bone structure at the onset of the remodeling needs to be realistic too. A start design is obtained by structural optimization...

  11. Evaluating accuracy of structural geometry by DXA methods with an anthropometric proximal femur phantom.

    Science.gov (United States)

    Khoo, B C C; Beck, T J; Brown, K; Price, R I

    2013-09-01

    DXA-derived bone structural geometry has been reported extensively but lacks an accuracy standard. In this study, we describe a novel anthropometric structural geometry phantom that simulates the proximal femur for use in assessing accuracy of geometry measurements by DXA or other X-ray methods. The phantom consists of seven different interchangeable neck modules with geometries that span the range of dimensions in an adult human proximal femur, including those representing osteoporosis. Ten repeated hip scans of each neck module using two current DXA scanner models were performed without repositioning. After scanner specific calibration, hip structure analysis was used to derive structural geometry. Scanner performance was similar for the two manufacturers. DXA-derived HSA geometric measurements were highly correlated with values derived directly from phantom geometry and position; R² between DXA and phantom measures were greater than 94% for all parameters, while precision error ranged between 0.3 and 3.9%. Despite high R² there were some systematic geometry errors for both scanners that were small for outer diameter, but increasing with complexity of geometrical parameter; e.g. buckling ratio. In summary, the anthropometric phantom and its fabrication concept were shown to be appropriate for evaluating proximal femoral structural geometry in two different DXA systems.

  12. Concomitant physeal fractures of the distal femur and proximal tibia

    Energy Technology Data Exchange (ETDEWEB)

    Sferopoulos, N.K. [Aristotle University of Thessaloniki, Department of Pediatric Orthopaedics, Thessaloniki (Greece)

    2005-07-01

    Concomitant physeal fractures of the distal femur and proximal tibia are very rare in children and adolescents. They are included in the classification of the ''floating knee'' injuries. Two cases with this combined injury are reported. They were closed injuries and in both patients the fracture of the proximal tibial epiphyseal plate was nondisplaced. In the first, a six-year-old girl, an early diagnosis was made radiographically. The intra-articular femoral fracture was operatively reduced and fixed. No growth abnormality was encountered 12 years later. The second patient, a 16-year-old boy, was conservatively treated for a displaced fracture-separation of the distal femoral epiphysis. Four weeks later there was physeal widening on both sides of the knee which indicated an associated fracture of the proximal tibial epiphyseal plate. One year after injury there was a varus deformity of the knee that was treated with a corrective osteotomy. Ten years later there is normal alignment of the leg. (orig.)

  13. Determination of muscle effort at the proximal femur rotation osteotomy

    Science.gov (United States)

    Sachenkov, O.; Hasanov, R.; Andreev, P.; Konoplev, Yu

    2016-11-01

    The paper formulates the problem of biomechanics of a new method for treatment of Legg-Calve-Perthes disease. Numerical calculations of the rotational flexion osteotomy have been carried out for a constructed mathematical model of the hip joint, taking into account the main set of muscles. The work presents the results of the calculations and their analysis. The results have been compared with the clinical data. The calculations of the reactive forces arising in the acetabulum and the proximal part of the femur allowed us to reveal that this reactive force changes both in value and direction. These data may be useful for assessing the stiffness of an external fixation device used in orthopedic intervention and for evaluating the compression in the joint.

  14. Spinal coronal profiles and proximal femur bone mineral density in adolescent idiopathic scoliosis.

    Science.gov (United States)

    Chen, Rui-Qiang; Watanabe, Kota; Hosogane, Naobumi; Hikata, Tomohiro; Iwanami, Akio; Ishii, Ken; Nakamura, Masaya; Toyama, Yoshiaki; Matsumoto, Morio

    2013-11-01

    Although the occurrence and progression of AIS has been linked to low bone mineral density (BMD), the relationships between spinal curvature and bilateral differences in proximal femur BMD are controversial. Few correlation studies have stratified patients by curve type. The purpose of this study was to evaluate the relationships between spinal coronal profile and bilateral differences in proximal femur BMD in patients with adolescent idiopathic scoliosis (AIS). This study included 67 patients with AIS who underwent posterior correction and fusion surgery between January 2009 and October 2011. The mean age at the time of surgery was 17.4 ± 4.1 years. Bilateral proximal femur BMD was measured before surgery by dual-energy X-ray absorptiometry. We compared the proximal femur BMDs by determining the bilateral BMD ratio (left proximal femur BMD divided by that of the right). We evaluated correlations between coronal parameters, obtained from preoperative radiographs, and the BMD ratio using Pearson's correlation analysis. Patients with Lenke type 1 curve (48; all with a right convex curve) had a mean bilateral proximal femur BMD ratio of 1.00 ± 0.04. Patients with Lenke type 5 curve (19; all with a left convex curve) had a mean bilateral proximal femur BMD ratio of 0.94 ± 0.04, indicating that the BMD in the proximal femur on the right side (concave) was greater than that in the left (convex). Coronal balance was significantly correlated with the BMD ratio in both the Lenke type 1 and type 5 groups, with a correlation coefficient of 0.46 and 0.50, respectively. The bilateral proximal femur BMD ratio was significantly correlated with the coronal balance in AIS patients. When the C7 plumb line was shifted toward one side, the BMD was greater in the contralateral proximal femur.

  15. A muscular imprint on the anterolateral surface of the proximal femurs of the Krapina Neandertal collection.

    Science.gov (United States)

    Belcastro, Maria Giovanna; Mariotti, Valentina

    2017-03-01

    The purpose of this study is to report and interpret a feature on the anterolateral surface of the proximal femurs of the Krapina hominid collection that we briefly described in 2006 (Periodicum Biologorum, 108, 319-329). We recorded the presence or absence of the feature in all the proximal femurs of the Krapina collection (six specimens recordable) and in 622 modern human adult femurs. The feature consists in a series of crests delimitating three raised or depressed areas. This feature has been found in three out of four adult Neandertal femurs observable. The two observable subadult Neandertal femurs do not show this character. None of the modern femurs displayed the feature. We interpret this feature as a muscular imprint, probably representing the m. vastus intermedius origin and discuss a possible interpretation. We did not find any other references for such imprint in the existing literature regarding the Neandertal femurs. © 2017 Wiley Periodicals, Inc.

  16. Uncemented allograft-prosthetic composite reconstruction of the proximal femur

    Directory of Open Access Journals (Sweden)

    Li Min

    2014-01-01

    Full Text Available Background: Allograft-prosthetic composite can be divided into three groups names cemented, uncemented, and partially cemented. Previous studies have mainly reported outcomes in cemented and partially cemented allograft-prosthetic composites, but have rarely focused on the uncemented allograft-prosthetic composites. The objectives of our study were to describe a surgical technique for using proximal femoral uncemented allograft-prosthetic composite and to present the radiographic and clinical results. Materials and Methods: Twelve patients who underwent uncemented allograft-prosthetic composite reconstruction of the proximal femur after bone tumor resection were retrospectively evaluated at an average followup of 24.0 months. Clinical records and radiographs were evaluated. Results: In our series, union occurred in all the patients (100%; range 5-9 months. Until the most recent followup, there were no cases with infection, nonunion of the greater trochanter, junctional bone resorption, dislocation, allergic reaction, wear of acetabulum socket, recurrence, and metastasis. But there were three periprosthetic fractures which were fixed using cerclage wire during surgery. Five cases had bone resorption in and around the greater trochanter. The average Musculoskeletal Tumor Society (MSTS score and Harris hip score (HHS were 26.2 points (range 24-29 points and 80.6 points (range 66.2-92.7 points, respectively. Conclusions: These results showed that uncemented allograft-prosthetic composite could promote bone union through compression at the host-allograft junction and is a good choice for proximal femoral resection. Although this technology has its own merits, long term outcomes are yet not validated.

  17. The effect of modular tapered fluted stems on proximal stress shielding in the human femur.

    Science.gov (United States)

    Hnat, William P; Conway, Justin S; Malkani, Arthur L; Yakkanti, Madhu R; Voor, Michael J

    2009-09-01

    The purpose of this study was to show a change in proximal femur surface strains following total hip arthroplasty and after the addition of BoneSource hydroxyapatite bone cement in the proximal region of an instrumented femur and to measure the surface strain on the proximal body. Seven third-generation composite femurs (Pacific Research Laboratories, Vashon, Wash) were instrumented with 12 uniaxial strain gages, 6 gages on the anterior face, and 6 gages on the posterior face of each femur. All femurs exhibited stress shielding since the strains in the proximal region were drastically reduced. There was a large decrease in strain in the mid-shaft region and small changes in strain in the distal region. The surface strains on the modular implant were relatively low.

  18. Pilot study on proximal femur strains during locomotion and fall-down scenario

    Energy Technology Data Exchange (ETDEWEB)

    Klodowski, Adam, E-mail: adam.klodowski@lut.fi; Valkeapaeae, Antti, E-mail: antti.valkeapaa@lut.fi; Mikkola, Aki, E-mail: aki.mikkola@lut.fi [Lappeenranta University of Technology (Finland)

    2012-09-15

    The most common and severe type of fracture among the elderly is known as a proximal femur fracture. Aging-related bone loss is one of the major contributing factors to increased likelihood of bone fracture. Specific exercises can be used to strain bones and increase bone strength to counter the effects of bone loss. The flexible multibody simulation approach can be used as a non-invasive method for estimating bone strains caused by physical activity. This method was recently used to analyze the strain of locomotion in regard to human femur and tibia leg bones. The current study focuses on strain analysis of the femoral neck. The research test person was a clinically healthy 65-year old Caucasian male. The computed tomography was used to build a geometrically accurate finite element model of the femur with inhomogeneous material properties derived from the voxel data. The anthropometric data was used to model the musculoskeletal system of the test person. The multibody skeletal model was utilized to estimate loading on the femoral neck during walking, which represents a routine daily activity. The flexible multibody simulation results were compared to strains that occurred during a simulated fall onto the greater trochanter of the femur. The fall simulation was made entirely using finite element software. Results from the finite element analysis were compared with the previous study showing that the test person does not belong to the high-risk hip fracture group. Finally, the estimated strains gathered from the walking simulation were compared to the strain values from the simulated fall-down scenario.

  19. ANATOMIC STUDY OF THE PROXIMAL THIRD OF THE FEMUR: FEMOROACETABULAR IMPACT AND THE CAM EFFECT

    OpenAIRE

    Labronici, Pedro José; Alves, Sergio Delmonte; da Silva, Anselmo Fernandes; Giuberti, Gilberto Ribeiro; Azevedo Neto, Justino Nóbrega de; Mezzalira Penedo, Jorge Luiz

    2015-01-01

    To analyze anatomical variations of the proximal end of femur that could cause a femoroacetabular impact. Methods: 199 skeletically mature anatomical specimens of femurs were used. The femurs were measured in order to determine the anteversion angle of the femoral neck, neckshaft angle, sphericity of the femoral head at anteroposterior and superoinferior, angle between epiphysis and the anterior femoral neck, angle between epiphysis and the neck at lateral plane, anteroposterior distance at 5...

  20. The shape of the early hominin proximal femur.

    Science.gov (United States)

    Harmon, Elizabeth H

    2009-06-01

    Postcranial skeletal variation among Plio-Pleistocene hominins has implications for taxonomy and locomotor adaptation. Although sample size constraints make interspecific comparisons difficult, postcranial differences between Australopithecus afarensis and Australopithecus africanus have been reported (McHenry and Berger: J Hum Evol 35 1998 1-22; Richmond et al.: J Hum Evol 43 [2002] 529-548; Green et al.: J Hum Evol 52 2007 187-200). Additional evidence indicates that the early members of the genus Homo show morphology like recent humans (e.g., Walker and Leakey: The Nariokotome Homo erectus skeleton. Cambridge: Harvard, 1993). Using a larger fossil sample than previous studies and novel methods, the early hominin proximal femur is newly examined to determine whether new data alter the current view of femoral evolution and inform the issue of interspecific morphological variation among australopiths. Two- and three-dimensional data are collected from large samples of recent humans, Pan, Gorilla, and Pongo and original fossil femora of Australopithecus, Paranthropus, and femora of African fossil Homo. The size-adjusted shape data are analyzed using principal components, thin plate spline analysis, and canonical variate analysis to assess shape variation. The results indicate that femora of fossil Homo are most similar to modern humans but share a low neck-shaft angle (NSA) with australopiths. Australopiths as a group have ape-like greater trochanter morphology. A. afarensis differs from P. robustus and A. africanus in attributes of the neck and NSA. However, interspecific femoral variation is low and australopiths are generally morphologically similar. Although the differences are not dramatic, when considered in combination with other postcranial evidence, the adaptive differences among australopiths in craniodental morphology may have parallels in the postcranium. Copyright 2009 Wiley-Liss, Inc.

  1. The Effect of Cement Placement on Augmentation of the Osteoporotic Proximal Femur

    OpenAIRE

    Sutter, Edward G.; Wall, Simon J.; Mears, Simon C; Belkoff, Stephen M.

    2010-01-01

    Femoroplasty, the augmentation of the proximal femur, has been shown in biomechanical studies to increase the energy required to produce a fracture and therefore may reduce the risk of such injuries. The purpose of our study was to test the hypotheses that: (1) 15 mL of cement was sufficient to mechanically augment the proximal femur, (2) there was no difference in augmentation effect between cement placement in the intertrochanteric region and in the femoral neck, and (3) cement placement in...

  2. Temporary antibiotic cement-covered gamma nail spacer for an infected nonunion of the proximal femur.

    Science.gov (United States)

    Rodriguez, Hugo; Ziran, Bruce H

    2007-01-01

    We report the case of an infected nonunion of the proximal femoral in an elderly patient. There was extensive involvement of the entire proximal femur precluding salvage. An impromptu use of a cephalomedullary nail coated with antibiotic-laden bone cement is described, followed by reimplantation with a revision-type proximal femoral prosthesis. The patient had resection of the proximal femur, placement of a temporary functional spacer, and reimplantation after a course of antibiotics, with good success. The method we describe is a reasonable alternative when standard off-the-shelf systems or other methods of temporary spacer creation are not available.

  3. Comparative morphometric analysis of the proximal femur of African hominids and felids

    Directory of Open Access Journals (Sweden)

    Andrew Gallagher

    2015-09-01

    Full Text Available Size and shape of the mammalian proximal femur and taxon-specific distinctions in the relative proportions of the proximal articulation, the femoral neck and the proximal femoral diaphysis, are critical determinants in its adaptation to differential biomechanical stresses and observed locomotor habitus in different taxa. The morphometrics of the proximal femur are considered equally critical in the assessment of locomotor habitus of extinct fossil mammals, particularly extinct Miocene anthropoids and Plio-Pleistocene hominins. Analyses of size and shape of k=10 dimensions of the proximal femur were undertaken for a large sample series of two extant mammal families the Felidae and Hominidae using conventional multivariate statistical procedures, commonly used size-correction methods, and post-hoc tests of significance. While significant differences in form do exist, there are equally striking convergences in the functional morphology of extant hominid and felid taxa. Multivariate and bivariate allometric analyses confirm that the proximal femur of these two mammalian families share a common underlying structure manifest in a shared first common principal component. Nevertheless, while considerable convergences in general form of the proximal femur of African hominids and large-bodied felids are apparent, there exist equally discreet distinctions which are consistent with the differential structural demands imposed by their distinct locomotor and behavioural habitus.

  4. Assessment of femur geometrical parameters using EOS™ imaging technology in patients with atypical femur fractures; preliminary results.

    Science.gov (United States)

    Morin, Suzanne N; Wall, Michelle; Belzile, Etienne L; Godbout, Benoit; Moser, Thomas P; Michou, Laëtitia; Ste-Marie, Louis-Georges; de Guise, Jacques A; Rahme, Elham; Brown, Jacques P

    2016-02-01

    Atypical femur fractures (AFF) arise in the subtrochanteric and diaphyseal regions. Because of this unique distribution, we hypothesized that patients with AFF demonstrate specific geometrical variations of their lower limb whereby baseline tensile forces applied to the lateral cortex are higher and might favor the appearance of these rare stress fractures, when exposed to bisphosphonates. Using the low irradiation 2D-3D X-ray scanner EOS™ imaging technology we aimed to characterize and compare femur geometric parameters between women who sustained bisphosphonate-associated AFF and those who had experienced similar duration of exposure to bisphosphonates but did not sustain fractures. Conditional logistic regression models were constructed to estimate the association between selected geometric parameters and the occurrence of AFF. We identified 16 Caucasian women with AFF and recruited 16 ethnicity-, sex-, age-, height- and cumulative bisphosphonate exposure-matched controls from local osteoporosis clinics. Compared to controls, those with AFF had more lateral femur bowing (-3.2° SD [3.4] versus -0.8° SD [1.9] p=0.02). In regression analysis, lateral femur bowing was associated with the risk of AFF (aOR 1.54; 95% CI 1.04-2.28, p=0.03). Women who sustained a subtrochanteric AFF demonstrated a lesser femoral neck shaft angle (varus geometry) than those with a fracture at a diaphyseal site (121.9 [3.6]° versus 127.6 [7.2]°, p=0.07), whereas femur bowing was more prominent in those with a diaphyseal fracture compared to those with a subtrochanteric fracture (-4.3 [3.2]° versus -0.9 [2.7]°, p=0.07). Our analyses support that subjects with AFF exhibit femoral geometry parameters that result in higher tensile mechanical load on the lateral femur. This may play a critical role in the pathogenesis of AFF and requires further evaluation in a larger size population. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Assessment of the individual fracture risk of the proximal femur by using statistical appearance models.

    Science.gov (United States)

    Schuler, Benedikt; Fritscher, Karl D; Kuhn, Volker; Eckstein, Felix; Link, Thomas M; Schubert, Rainer

    2010-06-01

    Standard diagnostic techniques to quantify bone mineral density (BMD) include dual-energy x-ray absorptiometry (DXA) and quantitative computed tomography. However, BMD alone is not sufficient to predict the fracture risk for an individual patient. Therefore, the development of tools, which can assess the bone quality in order to predict individual biomechanics of a bone, would mean a significant improvement for the prevention of fragility fractures. In this study, a new approach to predict the fracture risk of proximal femora using a statistical appearance model will be presented. 100 CT data sets of human femur cadaver specimens are used to create statistical appearance models for the prediction of the individual fracture load (FL). Calculating these models offers the possibility to use information about the inner structure of the proximal femur, as well as geometric properties of the femoral bone for FL prediction. By applying principal component analysis, statistical models have been calculated in different regions of interest. For each of these models, the individual model parameters for each single data set were calculated and used as predictor variables in a multilinear regression model. By this means, the best working region of interest for the prediction of FL was identified. The accuracy of the FL prediction was evaluated by using a leave-one-out cross validation scheme. Performance of DXA in predicting FL was used as a standard of comparison. The results of the evaluative tests demonstrate that significantly better results for FL prediction can be achieved by using the proposed model-based approach (R = 0.91) than using DXA-BMD (R = 0.81) for the prediction of fracture load. The results of the evaluation show that the presented model-based approach is very promising and also comparable to studies that partly used higher image resolutions for bone quality assessment and fracture risk prediction.

  6. Using a statistical appearance model to predict the fracture load of the proximal femur

    Science.gov (United States)

    Schuler, Benedikt; Fritscher, Karl D.; Kuhn, Volker; Eckstein, Felix; Schubert, Rainer

    2009-02-01

    Nowadays clinical diagnostic techniques like e.g. dual-energy X-ray absorptiometry are used to quantify bone quality. However, bone mineral density alone is not sufficient to predict biomechanical properties like the fracture load for an individual patient. Therefore, the development of tools, which can assess the bone quality in order to predicting individual biomechanics of a bone, would mean a significant improvement for the prevention of fractures. In this paper an approach to predict the fracture load of proximal femora by using a statistical appearance model will be presented. For this purpose, 96 CT-datasets of anatomical specimen of human femora are used to create statistical models for the prediction of the individual fracture load. Calculating statistical appearance models in different regions of interest by using principal component analysis (PCA) makes it possible to use geometric as well as structural information about the proximal femur. By regressing the output of PCA against the individual fracture load of 96 femora multi-linear regression models using a leave-one-out cross validation scheme have been created. The resulting correlations are comparable to studies that partly use higher image resolutions.

  7. Computed tomographic evaluation of the proximal femur: A predictive classification in displaced femoral neck fracture management

    Directory of Open Access Journals (Sweden)

    Narender Kumar Magu

    2014-01-01

    Full Text Available Background: Femoral neck fracture is truly an enigma due to the high incidence of avascular necrosis and nonunion. Different methods have been described to determine the size of the femoral head fragment, as a small head has been said to be associated with poor outcome and nonunion due to inadequate implant purchase in the proximal fragment. These methods were two dimensional and were affected by radiography techniques, therefore did not determine true head size. Computed tomography (CT is an important option to measure true head size as images can be obtained in three dimensions. Henceforth, we subjected patients to CT scan of hip in cases with displaced fracture neck of femur. The study aims to define the term "small head or inadequate size femoral head" objectively for its prognostic significance. Materials and Methods: 70 cases of displaced femoral neck fractures underwent CT scan preoperatively for proximal femoral geometric measurements of both hips. Dual energy X-ray absorptiometry scan was done in all cases. Patients were treated with either intertrochanteric osteotomy or lag screw osteosynthesis based on the size of the head fragment on plain radiographs. Results: The average femoral head fragment volume was 57 cu cm (range 28.3-84.91 cu cm; standard deviation 14 cu cm. Proximal fragment volume of >43 cu cm was termed adequate size (type I and of ≤43 cu cm as small femoral head (type II. Fractures which united (n = 54 had a relatively large average head size (59 cu cm when compared to fractures that did not (n = 16, which had a small average head size (49 cu cm and this difference was statistically significant. In type I fractures union rate was comparable in both osteotomy and lag screw groups (P > 0.05. Lag screw fixation failed invariably, while osteotomy showed good results in type II fractures (P < 0.05. Conclusion: Computed tomography scan of the proximal femur is advisable for measuring true size of head fragment. An objective

  8. Maturational timing does not predict HSA estimated adult bone geometry at the proximal femur.

    Science.gov (United States)

    Jackowski, Stefan A; Kontulainen, Saija A; Cooper, David M L; Lanovaz, Joel L; Baxter-Jones, Adam D G

    2011-12-01

    Late maturational timing is documented to be detrimental to bone strength primarily at the distal radius. Studies at the proximal femur have focused on bone mass and the results remain controversial. The purpose of this study was to examine the long term relationship between the onset of maturation and the development of estimated cross sectional area (CSA) and section modulus (Z) at the proximal femur. Two hundred and twenty six individuals (108 males and 118 females) from the Saskatchewan Pediatric Bone Mineral Accrual Study (PBMAS) were classified into maturity groups based on age of attainment of peak height velocity. CSA and Z were serially assessed at the narrow neck (NN), intertrochanter (IT) and proximal shaft (S) sites using hip structural analysis (HSA). Multilevel models were constructed to examine the development of CSA and Z by maturity group. Cross sectional observations indicated that during adolescence, early maturing males had significantly greater CSA and Z than late maturing males at all sites of the proximal femur, while early maturing females had greater Z at the NN and S, and greater CSA at the NN, IT and S sites compared to late maturing females. When age, body size, body composition, physical activity and dietary intake were controlled no significant effects of maturational timing were found at the NN, IT or S regions (p>0.05) in either males or females. In this population of healthy individuals there appears to be no effect of the onset of maturation on estimated CSA and Z development at the proximal femur in both males and females. This may be a result of the proximal femur's loading environment. Future research is required to determine the role of loading on the relationship between maturational timing and bone structure and strength development at the proximal femur. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Magnetic resonance imaging findings of osteoid osteoma of the proximal femur

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    Gaeta, Michele; Minutoli, Fabio; Pandolfo, Ignazio; Vinci, Sergio; Blandino, Alfredo [Department of Radiological Sciences, University of Messina, Policlinico ' ' G. Martino' ' , Via Consolare Valeria, 98100, Messina (Italy); D' Andrea, Letterio [Department of Orthopedics, University of Messina, Policlinico ' ' G. Martino' ' , Via Consolare Valeria, 98100, Messina (Italy)

    2004-09-01

    Osteoid osteoma (OO) is a benign bone tumor whose main radiological finding is nidus. OO of the proximal femur can also result in non-specific findings such as hip joint effusion, perinidal bone marrow edema and soft tissue mass. Since the nidus may be difficult to identify with MR, these non-specific findings can lead to erroneous diagnosis. Therefore, MR imaging technique should be optimized in order to identify nidus. Since MR imaging has assumed increasing importance in the evaluation of disorders of the hip, radiologists must be aware of the spectrum of findings of OO of the proximal femur. The aim of this pictorial review is to show the MR imaging findings of intra-articular and extra-articular OO of the proximal femur. (orig.)

  10. A device for in vivo measurements of quantitative ultrasound variables at the human proximal femur.

    Science.gov (United States)

    Barkmann, Reinhard; Laugier, Pascal; Moser, Urs; Dencks, Stefanie; Klausner, Michael; Padilla, Frédéric; Haïat, Guilleaume; Glüer, Claus-C

    2008-01-01

    Quantitative ultrasound (QUS) at the calcaneus has similar power as a bone mineral density (BMD)- measurement using DXA for the prediction of osteoporotic fracture risk. Ultrasound equipment is less expensive than DXA and free of ionizing radiation. As a mechanical wave, QUS has the potential of measuring different bone properties than dual X-ray absorptiometry (DXA,) which depends on X-ray attenuation and might be developed into a tool of comprehensive assessment of bone strength. However, site-specific DXA at the proximal femur shows best performance in the prediction of hip fractures. To combine the potential of QUS with measurements directly at the femur, we developed a device for in vivo QUS measurements at this site. Methods comprise ultrasound transmission through the bone, reflection from the bone surface, and backscatter from the inner trabecular structure. The complete area of the proximal femur can be scanned except at the femoral head, which interferes with the ilium. To avoid edge artifacts, a subregion of the proximal femur in the trochanteric region was selected as measurement region. First, in vivo measurements demonstrate a good signal to noise ratio and proper depiction of the proximal femur on an attenuation image. Our results demonstrate the feasibility of in vivo measurements. Further improvements can be expected by refinement of the scanning technique and data evaluation method to enhance the potential of the new method for the estimation of bone strength.

  11. A Skeletal Traction Technique for Proximal Femur Fracture Management in an Austere Environment.

    Science.gov (United States)

    Lidwell, David; Meghoo, Colin A

    2016-01-01

    Skeletal traction is a useful technique for managing proximal femur fractures in austere environments where fracture stabilization for this injury is difficult. We present a technique and a construct appropriate for field use that facilitates patient evacuation, and we provide guidelines for the use of this technique by an advanced medical provider managing these injuries. The objectives of this article are to enable to reader to (1) recognize the role of skeletal traction in managing proximal femur fractures in an austere environment, (2) identify the key steps in placing transfemoral skeletal traction pins, and (3) identify options and requirements for building a traction construct in resource-limited environments. 2016.

  12. In vivo measurements of ultrasound transmission through the human proximal femur.

    Science.gov (United States)

    Barkmann, Reinhard; Laugier, Pascal; Moser, Urs; Dencks, Stefanie; Klausner, Michael; Padilla, Frédéric; Haiat, Guillaume; Heller, Martin; Glüer, Claus-C

    2008-07-01

    Quantitative ultrasound (QUS) measurements can be used to estimate osteoporotic fracture risk. The commonly used variables are the speed of sound (SOS) and the frequency dependent sound attenuation (broadband ultrasound attenuation, [BUA]) of a wave propagating through the bone, preferably the calcaneus. The technology, so far, is less suitable for direct measurement in vivo at the spine or the femur for prediction of bone mineral density (BMD) or fracture risk at the main osteoporotic fracture sites. To improve the clinical performance of QUS, we built a device for direct QUS measurements at the human femur in vivo. In vivo images of ultrasound transmission at one of the main fracture sites, the proximal femur, could be acquired. The estimated precision of SOS measurements of 0.5% achieved at the femur is comparable with the precision of peripheral QUS devices.

  13. Physical therapy in the postoperative of proximal femur fracture in elderly. Literature review

    OpenAIRE

    Carneiro,Mariana Barquet; Alves,Débora Pinheiro Lédio; Mercadante, Marcelo Tomanik

    2013-01-01

    The proximal femoral fracture in the elderly is a serious public health problem. Surgical treatment of this fracture is used to reduce morbidity, together with postoperative physical therapy. The objective was to conduct a systematic review of physical therapy protocols in postoperative for fractures of the proximal femur in elderly. We selected randomized controlled trials in elderly in the past 10 years, in Portuguese and English. There were 14 articles in the literature. Physical therapy h...

  14. The best location for proximal locking screw for femur interlocking nailing: A biomechanical study

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    Ahmet A Karaarslan

    2016-01-01

    Conclusion: According to our findings, there is twice as much difference in locking screw bending resistance between these two application levels. To avoid proximal locking screw deformation, locking screws should be placed in the level of the lesser trochanter in nailing of 1/3 middle and distal femur fractures.

  15. Interpretation of hip fracture patterns using areal bone mineral density in the proximal femur.

    Science.gov (United States)

    Hey, Hwee Weng Dennis; Sng, Weizhong Jonathan; Lim, Joel Louis Zongwei; Tan, Chuen Seng; Gan, Alfred Tau Liang; Ng, Jun Han Charles; Kagda, Fareed H Y

    2015-12-01

    Bone mineral density scans are currently interpreted based on an average score of the entire proximal femur. Improvements in technology now allow us to measure bone density in specific regions of the proximal femur. The study attempts to explain the pathophysiology of neck of femur (NOF) and intertrochanteric/basi-cervical (IT) fractures by correlating areal BMD (aBMD) scores with fracture patterns, and explore possible predictors for these fracture patterns. This is a single institution retrospective study on all patients who underwent hip surgeries from June 2010 to August 2012. A total of 106 patients (44 IT/basi-cervical, 62 NOF fractures) were studied. The data retrieved include patient characteristics and aBMD scores measured at different regions of the contralateral hip within 1 month of the injury. Demographic and clinical characteristic differences between IT and NOF fractures were analyzed using Fisher's Exact test and two-sample t test. Relationship between aBMD scores and fracture patterns was assessed using multivariable regression modeling. After adjusted multivariable analysis, T-Troc and T-inter scores were significantly lower in intertrochanteric/basi-cervical fractures compared to neck of femur fractures (P = 0.022 and P = 0.026, respectively). Both intertrochanteric/basi-cervical fractures (mean T.Tot -1.99) and neck of femur fractures (mean T.Tot -1.64) were not found to be associated with a mean T.tot less than -2.5. However, the mean aBMD scores were consistently less than -2.5 for both intertrochanteric/basi-cervical fractures and neck of femur fractures. Gender and calcium intake at the time of injury were associated with specific hip fracture patterns (P = 0.002 and P = 0.011, respectively). Hip fracture patterns following low energy trauma may be influenced by the pattern of reduced bone density in different areas of the hip. Intertrochanteric/basi-cervical fractures were associated with significantly lower T-Troc and T-Inter scores

  16. Acetabular Protrusio and Proximal Femur Fractures in Patients With Osteogenesis Imperfecta.

    Science.gov (United States)

    Trehan, Samir K; Morakis, Emmanouil; Raggio, Cathleen L; Twomey, Kristin D; Green, Daniel W

    2015-09-01

    Osteogenesis imperfect (OI) is a genetic disorder characterized by increased bone fragility, frequent fractures, and extremity deformities among other clinical findings. A frequent radiographic finding in OI patients is acetabular protrusio (AP). We hypothesized that AP incidence would be significant in OI patients and highest among type III OI patients, who have a more severe disease phenotype. In addition, we hypothesized that there would be a correlation between AP and proximal femur fracture incidence. We retrospectively reviewed radiographs and medical records of 49 patients with OI evaluated at our institution. Demographic information and modified Sillence classification were recorded. AP was diagnosed using previously published radiographic criteria using the center-edge angle of Wiberg, acetabulum relative to the iliopectineal line, teardrop figure relative to the ilioischial (Kohler) line, and acetabulum relative to the ilioischial (Kohler) line. Medical record and radiographs were reviewed for evidence of proximal femur or acetabulum fracture. Associations between OI type, AP, and fracture incidence were examined with χ or Fisher exact tests. In this series of 49 OI patients, the overall incidence of AP was 55.1% (27/49) with the highest incidence among patients with type III OI (70.6%). There was an increased incidence of proximal femur, and particularly femoral neck, fractures among patients with AP compared with patients with normal hip anatomy. Overall, patients with AP had a 30% increased risk for proximal femur and acetabulum fractures (P=0.03). AP is a common deformity in OI patients (55.1%) and particularly type III OI (70.6%). Patients with AP have an increased risk for proximal femur fractures and particularly femoral neck fractures. This novel finding adds to the growing body of literature on clinical implications of AP in OI patients. Level IV-Retrospective case series.

  17. Limb-sparing surgery in a dog with osteosarcoma of the proximal femur.

    Science.gov (United States)

    Liptak, Julius M; Pluhar, G Elizabeth; Dernell, William S; Withrow, Stephen J

    2005-01-01

    To report successful limb-sparing surgery in a dog with a proximal femoral osteosarcoma (OSA) using a composite allograft-prosthetic technique. Case report. Client-owned dog. A stage IIB OSA of the proximal aspect of the femur was resected in accordance with oncologic and limb-sparing principles. The osseous defect was reconstructed with a proximal femoral allograft and cemented, long-stemmed femoral prosthesis. Soft tissue reconstruction was achieved by suturing host tendons to their respective allogeneic tendons on the allograft. Coxofemoral joint function was preserved using standard total hip arthroplasty techniques. Limb-sparing surgery of the proximal aspect of the femur using a composite allograft-prosthetic technique resulted in excellent limb function. Postoperative complications included aseptic loosening of the femoral composite graft and allograft nonunion, which required revision, traumatic implant luxation, and local tumor recurrence. Limb function was excellent after surgical stabilization of the allograft nonunion but deteriorated after implant luxation 270 days postlimb-sparing surgery. Pulmonary and skeletal metastases were diagnosed and local tumor recurrence suspected 596 and 650 days postoperatively, respectively. The dog was euthanatized 688 days after limb-sparing surgery as a result of progressive local and metastatic disease. Limb-sparing surgery for dogs with primary bone tumors of the proximal aspect of the femur is feasible with good functional results.

  18. [Gait analysis after rotationplasty hip surgery for malignant tumor of the proximal femur].

    Science.gov (United States)

    Donati, D; Benedetti, M G; Catani, F; Berti, L; Capanna, R

    2004-10-01

    Rotationplasty of the hip joint is a special surgical technique used for the treatment of malignant tumors of the proximal part of the femur. We report a clinical case and gait analysis results before and after rehabilitation training. Evaluation of joint motion, kinetic moments, and the electromyographic findings enabled us to document progressive adaptation of muscle and joint function to their new role in the motor pattern, demonstrating the exceptional strength of rotationplasty. Active control of two fulcrums in the lower limb, the pseudo hip proximally and the pseudo knee intermedially, makes this type of operation extremely advantageous compared to the alternative of hip disarticulation or hemipelvectomy. Total absence of pain together with the preservation of articular and cutaneous proprioception are important advantages. Rotationplasty is an attractive alternative for treatment of malignant tumors of the proximal part of the femur.

  19. Computed tomographic evaluation of the proximal femur: A predictive classification in displaced femoral neck fracture management.

    Science.gov (United States)

    Magu, Narender Kumar; Magu, Sarita; Rohilla, Rajesh Kumar; Batra, Amit; Jaipuria, Abhishek; Singh, Amanpreet

    2014-09-01

    Femoral neck fracture is truly an enigma due to the high incidence of avascular necrosis and nonunion. Different methods have been described to determine the size of the femoral head fragment, as a small head has been said to be associated with poor outcome and nonunion due to inadequate implant purchase in the proximal fragment. These methods were two dimensional and were affected by radiography techniques, therefore did not determine true head size. Computed tomography (CT) is an important option to measure true head size as images can be obtained in three dimensions. Henceforth, we subjected patients to CT scan of hip in cases with displaced fracture neck of femur. The study aims to define the term small head or inadequate size femoral head" objectively for its prognostic significance. 70 cases of displaced femoral neck fractures underwent CT scan preoperatively for proximal femoral geometric measurements of both hips. Dual energy X-ray absorptiometry scan was done in all cases. Patients were treated with either intertrochanteric osteotomy or lag screw osteosynthesis based on the size of the head fragment on plain radiographs. The average femoral head fragment volume was 57 cu cm (range 28.3-84.91 cu cm; standard deviation 14 cu cm). Proximal fragment volume of >43 cu cm was termed adequate size (type I) and of ≤43 cu cm as small femoral head (type II). Fractures which united (n = 54) had a relatively large average head size (59 cu cm) when compared to fractures that did not (n = 16), which had a small average head size (49 cu cm) and this difference was statistically significant. In type I fractures union rate was comparable in both osteotomy and lag screw groups (P > 0.05). Lag screw fixation failed invariably, while osteotomy showed good results in type II fractures (P femoral head size (type I and type II) is proposed. Osteosynthesis should be the preferred method of treatment in type I and osteotomy or prosthetic replacement is the method of choice for

  20. Surgically Relevant Bony and Soft Tissue Anatomy of the Proximal Femur

    Science.gov (United States)

    Philippon, Marc J.; Michalski, Max P.; Campbell, Kevin J.; Goldsmith, Mary T.; Devitt, Brian M.; Wijdicks, Coen A.; LaPrade, Robert F.

    2014-01-01

    Background: Hip endoscopy facilitates the treatment of extra-articular disorders of the proximal femur. Unfortunately, current knowledge of proximal femur anatomy is limited to qualitative descriptions and lacks surgically relevant landmarks. Purpose: To provide a quantitative and qualitative analysis of proximal femur anatomy in reference to surgically relevant bony landmarks. Study Design: Descriptive laboratory study. Methods: Fourteen cadaveric hemipelvises were dissected. A coordinate measuring device measured dimensions and interrelationships of the gluteal muscles, hip external rotators, pectineus, iliopsoas, and joint capsule in reference to osseous landmarks. Results: The vastus tubercle, superomedial border of the greater trochanter, and femoral head-neck junction were distinct and reliable osseous landmarks. The anteroinferior tip of the vastus tubercle was 17.1 mm (95% CI: 14.5, 19.8 mm) anteroinferior to the center of the gluteus medius lateral insertional footprint and was 22.9 mm (95% CI: 20.1, 25.7 mm) inferolateral to the center of the gluteus minimus insertional footprint. The insertions of the piriformis, conjoint tendon of the hip (superior gemellus, obturator internus, and inferior gemellus), and obturator externus were identified relative to the superomedial border of the greater trochanter. The relationship of the aforementioned footprints were 49% (95% CI: 43%, 54%), 42% (95% CI: 33%, 50%), and 64% (95% CI: 59%, 69%) from the anterior (0%) to posterior (100%) margins of the superomedial border of the greater trochanter, respectively. The hip joint capsule attached distally on the proximal femur 18.2 mm (95% CI: 14.2, 22.2 mm) from the head-neck junction medially on average. Conclusion: The vastus tubercle, superomedial border of the greater trochanter, and the femoral head-neck junction were reliable osseous landmarks for the identification of the tendinous and hip capsular insertions on the proximal femur. Knowledge of the

  1. The Analysis of Biomechanical Properties of Proximal Femur after Implant Removal

    Directory of Open Access Journals (Sweden)

    Jae Hyuk Yang

    2016-01-01

    Full Text Available Introduction. To compare the biomechanical stability of the femur following the removal of proximal femoral nail antirotation (PFNA-II and dynamic hip screw (DHS. Material and Methods. 56 paired cadaveric femurs were used as experimental and control groups. In the experimental group, PFNA-II and DHS were randomly inserted into femurs on both sides and then removed. Thereafter, compression load was applied until fracture occurred; biomechanical stability of the femurs and associated fracture patterns were studied. Results. The ultimate load and stiffness of the control group were 6227.8±1694.1 N and 990.5±99.8 N/mm, respectively. These were significantly higher than experimental group (p=0.014, <0.001 following the removal of PFNA-II (4085.6±1628.03 N and 656.3±155.3 N/mm and DHS (4001.9±1588.3 N and 656.3±155.3 N/mm. No statistical differences in these values were found between the 2 device groups (p=0.84, 0.71, regardless of age groups. However, fracture patterns were different between two devices, intertrochanteric and subtrochanteric fractures. Conclusions. Mechanical stability of the proximal femurs does not differ after the removal of 2 different of fixation devices regardless of the age. However, it was significantly lower compared to an intact femur. Different fracture patterns have been shown following the removal of different fixation devices as there are variations in the site of stress risers for individual implants.

  2. The association of distal femur and proximal tibia shape with sex: The Osteoarthritis Initiative.

    Science.gov (United States)

    Wise, Barton L; Liu, Felix; Kritikos, Lisa; Lynch, John A; Parimi, Neeta; Zhang, Yuqing; Lane, Nancy E

    2016-08-01

    Risk of knee osteoarthritis (OA) is much higher in women than in men. Previous studies have shown that bone shape is a risk factor for knee OA. However, few studies have examined whether knee bone shape differs between men and women. The purpose of the present study was to determine whether there are differences between men and women in knee bone shape. We used information from the NIH-funded Osteoarthritis Initiative (OAI), a cohort of persons aged 45-79 at baseline who either had symptomatic knee OA or were at high risk of it. Among participants aged between 45 and 60 years, we randomly sampled 340 knees without radiographic OA (i.e., Kellgren/Lawrence grade of 0 in central readings on baseline radiograph). We characterized distal femur and proximal tibia shape of these selected radiographs using statistical shape modeling (SSM). We performed linear regression analysis to examine the association between sex and each knee shape mode (proximal tibia and distal femur), adjusting for age, race, body mass index (BMI), and clinic site. The mean age was 52.7 years (±4.3 SD) for both men and women. There were 192 female and 147 male knees for the distal femur analysis. Thirteen modes were derived for femoral shape, accounting for 95.5% of the total variance. Distal femur mode 1 had the greatest difference in standardized score of knee shape between females and males (1.04, p femur and proximal tibia that form the knee joint differ by sex. Additional analyses are warranted to assess whether the difference in risk of OA between the sexes arises from bone shape differences. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Validation of subject-specific automated p-FE analysis of the proximal femur.

    Science.gov (United States)

    Trabelsi, Nir; Yosibash, Zohar; Milgrom, Charles

    2009-02-09

    The use of subject-specific finite element (FE) models in clinical practice requires a high level of automation and validation. In Yosibash et al. [2007a. Reliable simulations of the human proximal femur by high-order finite element analysis validated by experimental observations. J. Biomechanics 40, 3688-3699] a novel method for generating high-order finite element (p-FE) models from CT scans was presented and validated by experimental observations on two fresh frozen femurs (harvested from a 30 year old male and 21 year old female). Herein, we substantiate the validation process by enlarging the experimental database (54 year old female femur), improving the method and examine its robustness under different CT scan conditions. A fresh frozen femur of a 54 year old female was scanned under two different environments: in air and immersed in water (dry and wet CT). Thereafter, the proximal femur was quasi-statically loaded in vitro by a 1000N load. The two QCT scans were manipulated to generate p-FE models that mimic the experimental conditions. We compared p-FE displacements and strains of the wet CT model to the dry CT model and to the experimental results. In addition, the material assignment strategy was reinvestigated. The inhomogeneous Young's modulus was represented in the FE model using two different methods, directly extracted from the CT data and using continuous spatial functions as in Yosibash et al. [2007a. Reliable simulations of the human proximal femur by high-order finite element analysis validated by experimental observations. J. Biomechanics 40, 3688-3699]. Excellent agreement between dry and wet FE models was found for both displacements and strains, i.e. the method is insensitive to CT conditions and may be used in vivo. Good agreement was also found between FE results and experimental observations. The spatial functions representing Young's modulus are local and do not influence strains and displacements prediction. Finally, the p-FE results of

  4. SHORTAND MIDDLE-TERM RESULTS OF HIP ARTHROPLASTY FOR TUMORS OF THE PROXIMAL FEMUR

    Directory of Open Access Journals (Sweden)

    R. M. Tikhilov

    2014-01-01

    Full Text Available A purpose of the study was to evaluate the immediate and medium-term outcomes of the treatment of patients with primary tumor lesions of proximal femur after the lesion resection together with total hip arthroplastyby total revision systems. Material and methods. 34 patients with primary tumors of proximal femur [chondrosarcoma - 9 (26.5%,giant cell tumor - II (32.4%,osteosarcoma - 2 (5.8%, other malignancies - 5 (14.7%,benign neoplasms - 7 (20.6%] underwent the conserving surgery at R.R. Vreden Russian Research Institute of Traumatology and Orthopedics since 2003 through 2013. The follow-up was from one to five years. The age of patients ranged from 16 to 70 years, patients younger than 40 years accounted for 61.8%. Acetabulum was replaced by standard components. To replace post-resection defects of proximal femur, in 21 (61.8% patents revision legs of cementless fixation Wagner Revision (Zimmer were used, in 10 (29.4% - “Fenix”, and in 3 (8.8% - Solution (DePuy, J&J. Results. A technique of total hip arthroplasty with the use of revision systems demonstrated excellent and positive results in 32 (94.2% cases. Complications leading to revision surgery occurred in 3 (8.8% patients. Conclusion. The method allows achievement of favorable functional outcomes and early patients’ activation without worsening the oncologic component of treatment and being not inferior to expensive modular systems.

  5. Unusual proximal femur fracture in children treated with PHILOS plate and review of literature

    Directory of Open Access Journals (Sweden)

    Mukesh Kumar

    2017-01-01

    Full Text Available Fractures of the hip are uncommon in children with incidence is less than 1% in all paediatrics fracture. It requires careful attention because of the incidence of complications is high. There is no consensus over ideal treatment of each group, but there are different options for each group has been described in literature, we report a case of unusual proximal femur fracture in ten-year-old girl which is not described in literature in best of our knowledge. A 10 years old girl was brought to us with pain in right hip joint and inability to bear weight on right lower limb after road traffic accident (child was hit by a car while walking on the road. Evaluated and found to have fracture of proximal femur. fracture was fixed with long PHILOS plate, which united in eight weeks duration, implant was removed at 10 month. At present after 14 months, she is able to perform her routine activities comfortably. and her Harris hip score is 95. We propose to add this type of fracture as 5th type of Delbet's classification as the fracture pattern in my patient was not fitting in any group of Delbet's classification and it belongs to proximal femur group and anatomically this fracture pattern was next to type IV fracture. Uncommon fracture of hip in children can be expected, this type of fracture can be added as 5th type in Delbet's classification. Long term outcome and ideal treatment yet to be described.

  6. Asymmetry and structural system analysis of the proximal femur meta-epiphysis: osteoarticular anatomical pathology

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    Baydoun Safaa

    2008-02-01

    Full Text Available Abstract Background The human femur is commonly considered as a subsystem of the locomotor apparatus with four conspicuous levels of organization. This phenomenon is the result of the evolution of the locomotor apparatus, which encompasses both constitutional and individual variability. The work therein reported, therefore, underlies the significance of observing anatomical system analysis of the proximal femur meta-epiphysis in normal conditions, according to the anatomic positioning with respect to the right or left side of the body, and the presence of system asymmetry in the meta-epiphysis structure, thus indicating structural and functional asymmetry. Methods A total of 160 femur bones of both sexes were compiled and a morphological study of 15 linear and angulated parameters of proximal femur epiphysis was produced, thus defining the linear/angulated size of tubular bones. The parameters were divided into linear and angulated groups, while maintaining the motion of the hip joint and transmission of stress to the unwanted parts of the limb. Furthermore, the straight and vertical diameters of the femoral head and the length of the femoral neck were also studied. The angle between the neck and diaphysis, the neck antiversion and angle of rotation of the femoral neck were subsequently measured. Finally, the condylo-diaphyseal angle with respect to the axis of extremity was determined. To visualize the force of intersystem ties, we have used the method of correlation galaxy construction. Results The absolute numeral values of each linear parameter were transformed to relative values. The values of superfluity coefficient for each parameter in the right and left femoral bone groups were estimated and Pearson's correlation coefficient has been calculated (> 0.60. Retrospectively, the observed results have confirmed the presence of functional asymmetry in the proximal femur meta-epiphysis. On the basis of compliance or insignificant difference in

  7. Asymmetry and structural system analysis of the proximal femur meta-epiphysis: osteoarticular anatomical pathology.

    Science.gov (United States)

    Samaha, Ali A; Ivanov, Alexander V; Haddad, John J; Kolesnik, Alexander I; Baydoun, Safaa; Arabi, Maher R; Yashina, Irena N; Samaha, Rana A; Ivanov, Dimetry A

    2008-02-27

    The human femur is commonly considered as a subsystem of the locomotor apparatus with four conspicuous levels of organization. This phenomenon is the result of the evolution of the locomotor apparatus, which encompasses both constitutional and individual variability. The work therein reported, therefore, underlies the significance of observing anatomical system analysis of the proximal femur meta-epiphysis in normal conditions, according to the anatomic positioning with respect to the right or left side of the body, and the presence of system asymmetry in the meta-epiphysis structure, thus indicating structural and functional asymmetry. A total of 160 femur bones of both sexes were compiled and a morphological study of 15 linear and angulated parameters of proximal femur epiphysis was produced, thus defining the linear/angulated size of tubular bones. The parameters were divided into linear and angulated groups, while maintaining the motion of the hip joint and transmission of stress to the unwanted parts of the limb. Furthermore, the straight and vertical diameters of the femoral head and the length of the femoral neck were also studied. The angle between the neck and diaphysis, the neck antiversion and angle of rotation of the femoral neck were subsequently measured. Finally, the condylo-diaphyseal angle with respect to the axis of extremity was determined. To visualize the force of intersystem ties, we have used the method of correlation galaxy construction. The absolute numeral values of each linear parameter were transformed to relative values. The values of superfluidity coefficient for each parameter in the right and left femoral bone groups were estimated and Pearson's correlation coefficient has been calculated (> 0.60). Retrospectively, the observed results have confirmed the presence of functional asymmetry in the proximal femur meta-epiphysis. On the basis of compliance or insignificant difference in the confidence interval of the linear parameters, we

  8. Proximal femur of Australopithecus africanus from Member 4, Makapansgat, South Africa.

    Science.gov (United States)

    Reed, K E; Kitching, J W; Grine, F E; Jungers, W L; Sokoloff, L

    1993-09-01

    A left proximal femur (MLD 46) from Member 4, Makapansgat, South Africa is described and analyzed. It consists of the head, neck, and a small segment of the shaft that extends to just below the lesser trochanter. The femur exhibits degenerative joint disease in the form of marginal osteophyte formation and thus its taxonomic identity has been somewhat obscured. Consideration of all like-sized mammalian femora from Makapansgat suggests that the femur is that of either a felid or hominid. Comparison of MLD 46 to femora of extent and extinct felids reveals that MLD 46 does not possess two morphological features that are characteristic of felids, namely a deep, prolonged trochanteric fossa and a high neck-shaft angle. Simple shape variables (ratios) and multivariate analyses consistently place MLD 46 with modern and fossil hominids, and most closely align it with the australopithecines. We conclude that the femur is most reasonably attributable to Australopithecus africanus, which is the only hominid yet identified from Makapansgat. Despite its pathological condition, MLD 46 is the most complete proximal femur known for A. africanus, thereby permitting further morphological comparisons with homologues of A. afarensis and Paranthropus. Marginal osteophytes of mammalian femoral heads characteristically occur in individuals of advanced age, suggesting that MLD 46 may have lived some time with the disease. Finally, MLD 46 is considerably larger than the previously described specimen, Sts 14, from Sterkfontein Member 4. There may be as great a contrast in body size in A. africanus as there is between the large and small specimens of A. afarensis.

  9. Participation of osteoporosis in femoral neck fracture; Bone mineral measurement of proximal femur using quantitative computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Mizuno, Naoto (Gifu Prefectural Tajimi Hospital (Japan))

    1989-10-01

    Quantitative computed tomography (QCT) was used to measure bone mineral contents of the proximal femur. First, 62 specimens of cancellous bones of the proximal femur obtained at operation were burnt for mineral determination after preoperative QCT measurement to evaluate the relationship between QCT values and ash weight. The findings indicated that QCT measurement of proximal femur was as useful as that of the lumbar spine. Next, 10 groups of 50 men and 50 women ranging in age from the 5th to the 9th decade were tested to define the control mean and range of QCT mineral content of proximal femur, to compare with 32 cases of femoral neck fracture. In women with femoral neck fracture, QCT values of the femoral neck were less than those of the same normal age group except for cases of medial fracture in the 9th decade. This measurement might provide an index for fracture risk. (author).

  10. Pelvis width associated with bone mass distribution at the proximal femur in children 10–11 years old

    Science.gov (United States)

    Cardadeiro, Graça; Baptista, Fátima; Janz, Kathleen F.; Rodrigues, Luís A.; Sardinha, Luís B.

    2015-01-01

    Differences in skeletal geometry may generate different patterns of mechanical loading to bone. Impact and muscle loading during physical activity have been shown to influence skeletal geometry. The purpose of this study was to compare geometric measures of the pelvis and proximal femur (PF) of young children and to analyze the contribution and potential interaction of these geometric measures with physical activity on PF bone mass distribution. Participants were 149 girls and 145 boys, aged 10–11 years. Total body and left hip DXA scans were used to derive pelvic and PF geometric measures and PF bone mineral density (BMD) at the femoral neck (FN), trochanter (TR), and intertrochanter (IT). These subregions were used to represent bone mass distribution via three BMD ratios: FN:PF, TR:PF, and IT:PF. Physical activity was objectively measured using accelerometry, and maturity was estimated as the years of distance from peak height velocity. When compared to boys, girls had a wider pelvic diameter and greater interacetabular distances (p pelvis than boys, which accounted for proportionally greater BMD of the TR than other subregions of the PF. PMID:23744478

  11. Associations of vitamin D deficiency with postoperative gait and mortality among patients with fractures of the proximal femur

    OpenAIRE

    Gumieiro, David Nicoletti [UNESP; Pereira,Gilberto José Cação; Minicucci, Marcos Ferreira [UNESP; Ricciardi, Carlos Eduardo Inácio; Damasceno, Erick Ribeiro; Funayama, Bruno Schiavoni [UNESP

    2015-01-01

    OBJECTIVE: To assess whether serum vitamin D concentration is associated with gait status and mortality among patients with fractures of the proximal femur, six months after suffering the fracture.METHODS: Consecutive patients aged ≥65 years with fractures of the proximal femur, who were admitted to the orthopedics and traumatology ward of our service between January and December 2011, were prospectively evaluated. Clinical, radiological, epidemiological and laboratory analyses were performed...

  12. ANATOMIC STUDY OF THE PROXIMAL THIRD OF THE FEMUR: FEMOROACETABULAR IMPACT AND THE CAM EFFECT.

    Science.gov (United States)

    Labronici, Pedro José; Alves, Sergio Delmonte; da Silva, Anselmo Fernandes; Giuberti, Gilberto Ribeiro; de Azevedo Neto, Justino Nóbrega; Mezzalira Penedo, Jorge Luiz

    2009-01-01

    To analyze anatomical variations of the proximal end of femur that could cause a femoroacetabular impact. 199 skeletically mature anatomical specimens of femurs were used. The femurs were measured in order to determine the anteversion angle of the femoral neck, neckshaft angle, sphericity of the femoral head at anteroposterior and superoinferior, angle between epiphysis and the anterior femoral neck, angle between epiphysis and the neck at lateral plane, anteroposterior distance at 5mm of the head and neck junction and anteroposterior distance of the neck base. we found that the impact subgroup presented a significantly larger junction diameter of 5mm (p = 0.0001) and cam-head (%) (p= 0.0001), while base-cam (%) (p = 0.0001) showed a significantly smaller diameter than the subgroup without impact. It was identified that cam-head (%) ≤ 80 e base-cam (%) ≤ 73 were identified as the optimal impact points. our study showed that the effect cam, caused by anatomical variations of the proximal femoral end focused the head-neck junction and base of the neck-junction head-neck. These rates can be predictive factors of the impact.

  13. Morphometric Evaluation of Korean Femurs by Geometric Computation: Comparisons of the Sex and the Population

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    Ho-Jung Cho

    2015-01-01

    Full Text Available We measured 28 parameters of 202 femurs from Koreans by an automated geometric computation program using 3D models generated from computed tomography images. The measurement parameters were selected with reference to physical and forensic anthropology studies as well as orthopedic implant design studies. All measurements were calculated using 3D reconstructions on a computer using scientific computation language. We also analyzed sex and population differences by comparison with data from previous studies. Most parameters were larger in males than in females. The height, head diameter, head center offset, and chord length of the diaphysis, most parameters in the distal femur, and the isthmic width of the medullary canal were smaller in Koreans than in other populations. However, the neck-shaft angle, subtense, and width of the intercondylar notch in the distal femur were larger than those in other populations. The results of this study will be useful as a reference for physical and forensic anthropology as well as the design of medical devices suitable for Koreans.

  14. A proximal femur aneurysmal bone cyst resulting in amputation: a rare case report.

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    Khodamorad Jamshidi

    2015-02-01

    Full Text Available Aneurysmal bone cyst (ABC is blood filled expansile cystic lesion that most commonly occurs in patients during the second decade of their lives. Traditionally it has been described as a benign lesion but can be locally aggressive and result in the destruction of the involved bone. Treatment methods include surgical excision and curettage with or without bone grafting. We report a proximal femur aneurysmal bone cyst, which resulted in the amputation of the lower extremity, even though all available classic methods of treatment were applied for it.

  15. Radiographic anatomy of the proximal femur: femoral neck fracture vs. transtrochanteric fracture

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    Ana Lecia Carneiro Leão de Araújo Lima

    Full Text Available ABSTRACT OBJECTIVE: To evaluate the correlation between radiographic parameters of the proximal femur with femoral neck fractures or transtrochanteric fractures. METHODS: Cervicodiaphyseal angle (CDA, femoral neck width (FNW, hip axis length (HAL, and acetabular tear drop distance (ATD were analyzed in 30 pelvis anteroposterior view X-rays of patients with femoral neck fractures (n = 15 and transtrochanteric fractures (n = 15. The analysis was performed by comparing the results of the X-rays with femoral neck fractures and with transtrochanteric fractures. RESULTS: No statistically significant differences between samples were observed. CONCLUSION: There was no correlation between radiographic parameters evaluated and specific occurrence of femoral neck fractures or transtrochanteric fractures.

  16. Bone mineral loss at the proximal femur in acute spinal cord injury.

    Science.gov (United States)

    Edwards, W B; Schnitzer, T J; Troy, K L

    2013-09-01

    This study used quantitative computed tomography to assess changes in bone mineral at the proximal femur after acute spinal cord injury (SCI). Individuals with acute SCI experienced a marked loss of bone mineral from a combination of trabecular and endocortical resorption. Targeted therapeutic interventions are thus warranted in this population. SCI is associated with a rapid loss of bone mineral and an increased rate of fragility fracture. Some 10 to 20% of these fractures occur at the proximal femur. The purpose of this study was to quantify changes to bone mineral, geometry, and measures of strength at the proximal femur in acute SCI. Quantitative computed tomography analysis was performed on 13 subjects with acute SCI at serial time points separated by a mean of 3.5 months (range, 2.6-4.8 months). Changes in bone mineral content (BMC) and volumetric bone mineral density (vBMD) were quantified for integral, trabecular, and cortical bone at the femoral neck, trochanteric, and total proximal femur regions. Changes in bone volumes, cross-sectional areas, and surrogate measures of compressive and bending strength were also determined. During the acute period of SCI, subjects experienced a 2.7-3.3%/month reduction in integral BMC (p < 0.001) and a 2.5-3.1 %/month reduction in integral vBMD (p < 0.001). Trabecular BMC decreased by 3.1-4.7 %/month (p < 0.001) and trabecular vBMD by 2.8-4.4 %/month (p < 0.001). A 3.9-4.0 %/month reduction was observed for cortical BMC (p < 0.001), while the reduction in cortical vBMD was noticeably lower (0.8-1.0 %/month; p ≤ 0.01). Changes in bone volume and cross-sectional area suggested that cortical bone loss occurred primarily through endosteal resorption. Declines in bone mineral were associated with a 4.9-5.9 %/month reduction in surrogate measures of strength. These data highlight the need for therapeutic interventions in this population that target both trabecular and endocortical bone mineral

  17. The combination of structural parameters and areal bone mineral density improves relation to proximal femur strength

    DEFF Research Database (Denmark)

    Hansen, Stinus; Jensen, Jens-Erik Beck; Ahrberg, Fabian

    2011-01-01

    -one human proximal femur specimens (8 men and 23 women, median age 74 years, range 50-89) were examined with HR-pQCT at four regions of interest (femoral head, neck, major and minor trochanter) with 82 μm and in a subgroup (n = 17) with 41 μm resolution. Separate analyses of cortical and trabecular geometry...... fractures were confirmed. Geometry, vBMD, microarchitecture, and aBMD correlated significantly with MCS, with Spearman's correlation coefficients up to 0.77, 0.89, 0.90, and 0.85 (P ...

  18. A comparison of bone mineral density in osteoporotic fracture of the proximal femur using dual energy X-ray absorptiometry

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Seok; Yoo, Beong Gyu [Wonkwang Health Science College, Iksan (Korea, Republic of); Kim, Keung Sik [Yonsei University Yong Dong Severance Hospital, Seoul (Korea, Republic of)

    2000-04-15

    There were some controversies about direct cause of hip fracture. We attempted to look at 40 osteoporotic proximal femur fractures in women over 50 years between March in 1999 and February in 2000. The bone density of the fracture group and the healthy 85 control group was measured by Dual Energy X-ray absorptiometry (DEXA). The result was compared using age matched paired T test. The results were as follows: The femoral neck fractures were 14 cases and the trochanteric fractures were 26 cases. Mean age at a fracture was 67.1 years in neck fracture group and 76.5 years in trochanteric fracture. In the control group, the bone density of both side of the proximal femur was measured and it showed statistically no difference between both sides in same person. The bone density of neck, Ward's triangle, trochanter (P<0.05) and lumbar spine (P<0.001) was significantly reduced in the proximal femoral fracture group comparing with the control group. The bone density of neck, Ward's triangle, trochanter (P<0.05) was significantly reduced in the proximal femoral neck fracture group comparing with the control group, but there was no statistical difference in lumbar spine comparing with the control group. The bone density of neck, Ward's triangle, trochanter and lumbar spine (P<0.001) was significantly reduced in the proximal femoral neck fracture group comparing with the control group. We concluded that the bone mineral densities (BMD) of proximal femur and lumbar spine had decreased in hip fractures but that the bone mineral density and T-score % of the proximal femur were statistically lower than that of the lumbar spine. We suggest that measuring the bone mineral density of the proximal femur may reflect the weakness of the proximal femur more precisely than measuring the bone mineral density of the lumbar spine.

  19. The impact of proximal femur geometry on fracture type--a comparison between cervical and trochanteric fractures with two parameters.

    Science.gov (United States)

    Panula, J; Sävelä, M; Jaatinen, P T; Aarnio, P; Kivelä, S-L

    2008-01-01

    Only a few studies have tested the ability of proximal femur geometry parameters to discriminate between cervical hip fractures and those of the trochanter. The main objective of this study was to evaluate the geometrical differences between these two fracture types by measuring the neck shaft angle (NSA) and the femoral neck axis length (FNAL). We also compared the distributions of these parameters and the distributions of fracture type by gender. A retrospective analysis was made in a population-based material of 428 hip fractures collected during a two-year period from 1999 to 2000 (323 women and 105 men aged 65 years or older). NSA and FNAL were manually measured from pelvic radiographs. No significant differences in NSA or FNAL were found between cervical and trochanteric hip fractures in women or in men. Men had significantly higher NSA and FNAL than women. Age was not related to these geometrical parameters. The distributions by fracture type were similar in both genders. The different pathogenesis of cervical and trochanteric hip fractures cannot be explained by NSA or FNAL. A standardized measurement setup is needed when evaluating the role of hip geometry in fracture patients.

  20. Fractures around a previous fixation of proximal femur. A simple solution to a complex problem.

    Directory of Open Access Journals (Sweden)

    Fernando Manuel Bidolegui

    2016-05-01

    Full Text Available The number of hip fractures in the elderly growth with the increase in life expectancy. Therefore meet with a femur fractured, distal to a previously  implant fixation used in intertrochanteric femur fractures as dynamic hip screw or fixed angle plate, is not an uncommon scenario despite year mortality of hip fracture of 30 to 50%. Given this situation, we used a retrograde intramedullary nail associated with extracting screws percutaneously prior implant. We present 8 cases in patients with an average age of 85.6 years, 5 female and 3 male with a time from the proximal femur fixation to the  new fracture average 3.5 years. Will we track 36 months and we evaluated postoperative mobility and pain getting a consolidation of the fracture in all cases. We found this technique effective; capable of achieving stable fixation without adding morbidity due to the possibility of overlapping two implants decreasing the possibility of potential new interimplantes fracture.

  1. Integrated remodeling-to-fracture finite element model of human proximal femur behavior.

    Science.gov (United States)

    Hambli, Ridha; Lespessailles, Eric; Benhamou, Claude-Laurent

    2013-01-01

    The purpose of this work was to develop an integrated remodeling-to-fracture finite element model allowing for the combined simulation of (i) simulation of a human proximal femur remodeling under a given boundary conditions, (ii) followed by the simulation of its fracture behavior (force-displacement curve and fracture pattern) under quasi-static load. The combination of remodeling and fracture simulation into one unified model consists in considering that the femur properties resulting from the remodeling simulation correspond to the initial state for the fracture prediction. The remodeling model is based on phenomenological one based on a coupled strain and fatigue damage stimulus. The fracture model is based on continuum damage mechanics in order to predict the progressive fracturing process which allows to predict the fracture pattern and the complete force-displacement curve under quasi-static load. To prevent mesh-dependence that generally affects the damage propagation rate, regularization technique was applied in the current work. To investigate the potential of the proposed unified remodeling-to-fracture model, we performed remodeling simulations on a 3D proximal femur model for a duration of 365 days under five different daily loading conditions followed by a side fall fracture simulation reproducing previously published experimental tests (de Bakker et al. (2009), case C, male, 72 years old). We show here that the implementation of an integrated remodeling-to-fracture model provides more realistic prediction strategy to assess the bone remodeling effects on the fracture risk of bone. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Computational study of Wolff's law with trabecular architecture in the human proximal femur using topology optimization.

    Science.gov (United States)

    Jang, In Gwun; Kim, Il Yong

    2008-08-07

    In the field of bone adaptation, it is believed that the morphology of bone is affected by its mechanical loads, and bone has self-optimizing capability; this phenomenon is well known as Wolff's law of the transformation of bone. In this paper, we simulated trabecular bone adaptation in the human proximal femur using topology optimization and quantitatively investigated the validity of Wolff's law. Topology optimization iteratively distributes material in a design domain producing optimal layout or configuration, and it has been widely and successfully used in many engineering fields. We used a two-dimensional micro-FE model with 50 microm pixel resolution to represent the full trabecular architecture in the proximal femur, and performed topology optimization to study the trabecular morphological changes under three loading cases in daily activities. The simulation results were compared to the actual trabecular architecture in previous experimental studies. We discovered that there are strong similarities in trabecular patterns between the computational results and observed data in the literature. The results showed that the strain energy distribution of the trabecular architecture became more uniform during the optimization; from the viewpoint of structural topology optimization, this bone morphology may be considered as an optimal structure. We also showed that the non-orthogonal intersections were constructed to support daily activity loadings in the sense of optimization, as opposed to Wolff's drawing.

  3. Generation of an Atlas of the Proximal Femur and Its Application to Trabecular Bone Analysis

    Science.gov (United States)

    Carballido-Gamio, Julio; Folkesson, Jenny; Karampinos, Dimitrios C.; Baum, Thomas; Link, Thomas M.; Majumdar, Sharmila; Krug, Roland

    2013-01-01

    Automatic placement of anatomically corresponding volumes of interest and comparison of parameters against a standard of reference are essential components in studies of trabecular bone. Only recently, in vivo MR images of the proximal femur, an important fracture site, could be acquired with high-spatial resolution. The purpose of this MRI trabecular bone study was two-fold: (1) to generate an atlas of the proximal femur to automatically place anatomically corresponding volumes of interest in a population study and (2) to demonstrate how mean models of geodesic topological analysis parameters can be generated to be used as potential standard of reference. Ten females were used to generate the atlas and geodesic topological analysis models, and 10 females were used to demonstrate the atlas-based trabecular bone analysis. All alignments were based on three-dimensional (3D) multiresolution affine transformations followed by 3D multiresolution free-form deformations. Mean distances less than 1 mm between aligned femora, and sharp edges in the atlas and in fused gray-level images of registered femora indicated that the anatomical variability was well accommodated and explained by the free-form deformations. PMID:21432904

  4. Predicting the biomechanical strength of proximal femur specimens with Minkowski functionals and support vector regression

    Science.gov (United States)

    Yang, Chien-Chun; Nagarajan, Mahesh B.; Huber, Markus B.; Carballido-Gamio, Julio; Bauer, Jan S.; Baum, Thomas; Eckstein, Felix; Lochmüller, Eva-Maria; Link, Thomas M.; Wismüller, Axel

    2014-03-01

    Regional trabecular bone quality estimation for purposes of femoral bone strength prediction is important for improving the clinical assessment of osteoporotic fracture risk. In this study, we explore the ability of 3D Minkowski Functionals derived from multi-detector computed tomography (MDCT) images of proximal femur specimens in predicting their corresponding biomechanical strength. MDCT scans were acquired for 50 proximal femur specimens harvested from human cadavers. An automated volume of interest (VOI)-fitting algorithm was used to define a consistent volume in the femoral head of each specimen. In these VOIs, the trabecular bone micro-architecture was characterized by statistical moments of its BMD distribution and by topological features derived from Minkowski Functionals. A linear multiregression analysis and a support vector regression (SVR) algorithm with a linear kernel were used to predict the failure load (FL) from the feature sets; the predicted FL was compared to the true FL determined through biomechanical testing. The prediction performance was measured by the root mean square error (RMSE) for each feature set. The best prediction result was obtained from the Minkowski Functional surface used in combination with SVR, which had the lowest prediction error (RMSE = 0.939 ± 0.345) and which was significantly lower than mean BMD (RMSE = 1.075 ± 0.279, pfemur specimens with Minkowski Functionals extracted from on MDCT images used in conjunction with support vector regression.

  5. Model-based estimation of quantitative ultrasound variables at the proximal femur.

    Science.gov (United States)

    Dencks, Stefanie; Barkmann, Reinhard; Padilla, Frédéric; Laugier, Pascal; Schmitz, Georg; Glüer, Claus-C

    2008-01-01

    To improve the prediction of the osteoporotic fracture risk at the proximal femur we are developing a scanner for quantitative ultrasound (QUS) measurements at this site. Due to multipath transmission in this complex shaped bone, conventional signal processing techniques developed for QUS measurements at peripheral sites frequently fail. Therefore, we propose a model-based estimation of the QUS variables and analyze the performance of the new algorithm. Applying the proposed method to QUS scans of excised proximal femurs increased the fraction of evaluable signals from approx. 60% (using conventional algorithms) to 97%. The correlation of the standard QUS variables broadband ultrasound attenuation (BUA) and speed of sound (SOS) with the established variable bone mineral density (BMD) reported in previous studies is maintained (BUA/BMD: r(2) = 0.69; SOS/BMD: r(2) = 0.71; SOS+BUA/BMD: r(2) = 0.88). Additionally, different wave types could be clearly detected and characterized in the trochanteric region. The ability to separate superimposed signals with this approach opens up further diagnostic potential for evaluating waves of different sound paths and wave types through bone tissue.

  6. Guided Growth of the Proximal Femur for Hip Displacement in Children With Cerebral Palsy.

    Science.gov (United States)

    Lee, Wei-Chun; Kao, Hsuan-Kai; Yang, Wen-E; Ho, Pei-Chi; Chang, Chia-Hsieh

    2016-01-01

    Guided growth by 1 eccentric transphyseal screw has been used to correct lower limb deformities. Pilot animal studies showed encouraging results in producing varus deformity in the proximal femur. The purpose of this study was to report the preliminary results of guided growth surgery to treat spastic hip displacement. This case series study included consecutive patients who received soft-tissue release and guided growth at the proximal femur from January 2004 to May 2012 with minimal 2-year follow-up. Surgical indications were children with spastic cerebral palsy aged 4 to 10 years, a gross motor function classification system level IV or V, and hip displacement on 1 or both sides. Study outcomes were Reimer's migration percentage (MP) and the head-shaft angle (HSA). Nine children with 13 spastic displaced hips received surgery at the age of 6.2 years and were followed up for a mean of 45.6 months. The mean MP improved significantly from 52.2% preoperatively to 45.8% at 3 months, 40.3% at 1 year, and 37.1% at 2 years after operation. HSA was unchanged in the first 3 months, and deceased from 173.3 to 166.4 degrees at 1 year (Pcoxa valga in spastic hip displacement in nonambulant cerebral palsy children. Level IV-therapeutic, case series.

  7. Size and shape variation in the proximal femur of Australopithecus africanus.

    Science.gov (United States)

    Harmon, Elizabeth

    2009-06-01

    Aside from use as estimates of body mass dimorphism and fore to hind limb joint size comparisons, postcranial elements have not often contributed to assessments of variation in Australopithecus africanus. Meanwhile, cranial, facial, and dental size variation is interpreted to be high or moderately high. Further, the cranial base and face express patterns of structural (shape) variation, which are interpreted by some as evidence for the presence of multiple species. Here, the proximal femur is used to consider postcranial size and shape variation in A. africanus. Original fossils from Makapansgat and Sterkfontein, and samples from Homo, Pan, Gorilla, and Pongo were measured. Size variation was assessed by comparing the A. africanus coefficient of variation to bootstrapped distributions of coefficient of variation samples for each taxon. Shape variation was assessed from isometrically adjusted shape variables. First, the A. africanus standard deviation of log transformed shape variables was compared to bootstrapped distributions of logged standard deviations in each taxon. Second, shape variable based Euclidean distances between fossil pairs were compared to pairwise Euclidean distance distributions in each reference taxon. The degree of size variation in the A. africanus proximal femur is consistent with that of a single species, and is most comparable to Homo and Pan, lower than A. afarensis, and lower than some estimates of cranial and dental variation. Some, but not all, shape variables show more variation in A. africanus than in extant taxa. The degree of shape difference between some fossils exceeds the majority of pairwise differences in the reference taxa. Proximal femoral shape, but not size, variation is consistent with high estimates of A. africanus cranial variation.

  8. Comparison of Percutaneous Cementoplasty with and Without Interventional Internal Fixation for Impending Malignant Pathological Fracture of the Proximal Femur

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Qing-Hua, E-mail: ddqinghua-tian@163.com; He, Cheng-Jian, E-mail: tianhechengjian@163.com; Wu, Chun-Gen, E-mail: 649514608@qq.com; Li, Yong-Dong, E-mail: tianliyongdong@163.com; Gu, Yi-Feng, E-mail: tianyifenggu@163.com; Wang, Tao, E-mail: tianandwangtao@163.com; Xiao, Quan-Ping, E-mail: tianxiaoquanping@163.com; Li, Ming-Hua, E-mail: tianminghuali@163.com [Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Department of Diagnostic and Interventional Radiology (China)

    2016-01-15

    PurposeTo compare the efficacy of percutaneous cementoplasty (PCP) with and without interventional internal fixation (IIF) on malignant impending pathological fracture of proximal femur.MethodsA total of 40 patients with malignant impending pathological fracture of proximal femur were selected for PCP and IIF (n = 19, group A) or PCP alone (n = 21, group B) in this non-randomized prospective study. Bone puncture needles were inserted into the proximal femur, followed by sequential installation of the modified trocar inner needles through the puncture needle sheath. Then, 15–45 ml cement was injected into the femur lesion.ResultsThe overall excellent and good pain relief rate during follow-ups were significantly higher in group A than that in group B (89 vs. 57 %, P = 0.034). The average change of VAS, ODI, KPS, and EFES in group A were significantly higher than those in group B at 1-, 3-, 6-month, 1-year (P < 0.05). Meanwhile, The stability of the treated femur was significantly higher in group A than that in group B (P < 0.05).ConclusionPCP and IIF were not only a safe and effective procedure, but resulted in greater pain relief, bone consolidation, and also reduced the risk of fracture than the currently recommended approach of PCP done on malignant proximal femoral tumor.

  9. Structural patterns of the proximal femur in relation to age and hip fracture risk in women

    Science.gov (United States)

    Carballido-Gamio, Julio; Harnish, Roy; Saeed, Isra; Streeper, Timothy; Sigurdsson, Sigurdur; Amin, Shreyasee; Atkinson, Elizabeth J.; Therneau, Terry M.; Siggeirsdottir, Kristin; Cheng, Xiaoguang; Melton, L. Joseph; Keyak, Joyce; Gudnason, Vilmundur; Khosla, Sundeep; Harris, Tamara B.; Lang, Thomas F.

    2013-01-01

    Fractures of the proximal femur are the most devastating outcome of osteoporosis. It is generally understood that age-related changes in hip structure confer increased risk, but there have been few explicit comparisons of such changes in healthy subjects to those with hip fracture. In this study, we used quantitative computed tomography and tensor-based morphometry (TBM) to identify three-dimensional internal structural patterns of the proximal femur associated with age and with incident hip fracture. A population-based cohort of 349 women representing a broad age range (21–97 years) were included in this study, along with a cohort of 222 older women (mean age 79±7 years) with (n=74) and without (n=148) incident hip fracture. Images were spatially normalized to a standardized space, and age- and fracture-specific morphometric features were identified based on statistical maps of shape features described as local changes of bone volume. Morphometric features were visualized as maps of local contractions and expansions, and significance was displayed as Student’s t-test statistical maps. Significant age-related changes included local expansions of regions low in volumetric bone mineral density (vBMD) and local contractions of regions high in vBMD. Some significant fracture-related features resembled an accentuated aging process, including local expansion of the superior aspect of the trabecular bone compartment in the femoral neck, with contraction of the adjoining cortical bone. However, other features were observed only in the comparison of hip fracture subjects with age-matched controls including focal contractions of the cortical bone at the superior aspect of the femoral neck, the lateral cortical bone just inferior to the greater trochanter, and the anterior intertrochanteric region. Results of this study support the idea that the spatial distribution of morphometric features is relevant to age-related changes in bone and independently to fracture risk. In

  10. QCT of the proximal femur--which parameters should be measured to discriminate hip fracture?

    Science.gov (United States)

    Museyko, O; Bousson, V; Adams, J; Laredo, J -D; Engelke, K

    2016-03-01

    For quantitative computed tomography (QCT), most relevant variables to discriminate hip fractures were determined. A multivariate analysis showed that trabecular bone mineral density (BMD) of the trochanter with "cortical" thickness of the neck provided better fracture discrimination than total hip integral BMD. A slice-by-slice analysis of the neck or the inclusion of strength-based parameters did not improve fracture discrimination. For QCT of the proximal femur, a large variety of analysis parameters describing bone mineral density, geometry, or strength has been considered. However, in each given study, generally just a small subset was used. The aim of this study was to start with a comprehensive set and then select a best subset of QCT parameters for discrimination of subjects with and without acute osteoporotic hip fractures. The analysis was performed using the population of the European Femur Fracture (EFFECT) study (Bousson et al. J Bone Min Res: Off J Am Soc Bone Min Res 26:881-893, 2011). Fifty-six female control subjects (age 73.2 ± 9.3 years) were compared with 46 female patients (age 80.9 ± 11.1 years) with acute hip fractures. The QCT analysis software MIAF-Femur was used to virtually dissect the proximal femur and analyze more than 1000 parameters, predominantly in the femoral neck. A multivariate best-subset analysis was used to extract the parameters best discriminating hip fractures. All results were adjusted for age, height, and weight differences between the two groups. For the discrimination of all proximal hip fractures as well as for cervical fractures alone, the measurement of neck parameters suffices (area under the curve (AUC) = 0.84). Parameters characterizing bone strength are discriminators of hip fractures; however, in multivariate models, only "cortical" cross-sectional area in the neck center remained as a significant contributor. The combination of one BMD parameter, trabecular BMD of the trochanter, and one geometry

  11. Radiographic study on the anatomical characteristics of the proximal femur in Brazilian adults

    Directory of Open Access Journals (Sweden)

    Tércio Henrique Soares de Farias

    2015-02-01

    Full Text Available OBJECTIVE: To ascertain the geometry of the femur in the Brazilian population by means of a radiographic study and to correlate the values with regard to sex and right/left side.METHODS: Five hundred anteroposterior radiographs of the pelvis of skeletally mature patients (250 of each sex who did not present any osteoarthrosis, fractures or tumoral or infectious lesions were analyzed. The length and width of the femoral neck, length of the femoral axis, neck-shaft angle and femoral offset were measured.RESULTS: The following means were observed: 36.54 mm for the length of the femoral neck; 37.48 mm for the width of the femoral neck; 108.42 mm for the length of the femoral axis; 130.47° for the neck-shaft angle; and 44.4 mm for the femoral offset.CONCLUSION: The mean values for the main measurements on the proximal femur in Brazilians differed from those of previous studies. It could also be shown that there was a statistically significant mean difference between men and women for all the variables, both on the left and on the right side, and that the men had greater means than the women.

  12. Development of a balanced experimental-computational approach to understanding the mechanics of proximal femur fractures.

    Science.gov (United States)

    Helgason, B; Gilchrist, S; Ariza, O; Chak, J D; Zheng, G; Widmer, R P; Ferguson, S J; Guy, P; Cripton, P A

    2014-06-01

    The majority of people who sustain hip fractures after a fall to the side would not have been identified using current screening techniques such as areal bone mineral density. Identifying them, however, is essential so that appropriate pharmacological or lifestyle interventions can be implemented. A protocol, demonstrated on a single specimen, is introduced, comprising the following components; in vitro biofidelic drop tower testing of a proximal femur; high-speed image analysis through digital image correlation; detailed accounting of the energy present during the drop tower test; organ level finite element simulations of the drop tower test; micro level finite element simulations of critical volumes of interest in the trabecular bone. Fracture in the femoral specimen initiated in the superior part of the neck. Measured fracture load was 3760N, compared to 4871N predicted based on the finite element analysis. Digital image correlation showed compressive surface strains as high as 7.1% prior to fracture. Voxel level results were consistent with high-speed video data and helped identify hidden local structural weaknesses. We found using a drop tower test protocol that a femoral neck fracture can be created with a fall velocity and energy representative of a sideways fall from standing. Additionally, we found that the nested explicit finite element method used allowed us to identify local structural weaknesses associated with femur fracture initiation. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  13. The chondrogenic response to exercise in the proximal femur of normal and mdx mice

    Directory of Open Access Journals (Sweden)

    Nye David J

    2010-09-01

    Full Text Available Abstract Background Submaximal exercise is used in the management of muscular dystrophy. The effects of mechanical stimulation on skeletal development are well understood, although its effects on cartilage growth have yet to be investigated in the dystrophic condition. The objective of this study was to investigate the chondrogenic response to voluntary exercise in dystrophin-deficient mice. Methods Control and dystrophin-deficient (mdx mice were divided into sedentary and exercise-treated groups and tested for chondral histomorphometric differences at the proximal femur. Results Control mice ran 7 km/week further than mdx mice on average, but this difference was not statistically significant (P > 0.05. However, exercised control mice exhibited significantly enlarged femur head diameter, articular cartilage thickness, articular cartilage tissue area, and area of calcified cartilage relative to sedentary controls and exercised mdx mice (P Conclusions Mdx mice exhibit a reduced chondrogenic response to increased mechanical stimulation relative to controls. However, no significant reduction in articular dimensions was found, indicating loss of chondral tissue may not be a clinical concern with dystrophinopathy.

  14. Surgical Treatment of Undisplaced Femur Neck Fractures in Dementia Patients Using Proximal Femoral Nail Antirotation.

    Science.gov (United States)

    Park, Bong-Ju; Cho, Hong-Man; Min, Woong-Bae

    2015-09-01

    People with dementia have poor mobility and discharge outcomes following hip fractures. The purpose of this study was to evaluate the clinical and radiological results of internal fixation of undisplaced femur neck fractures (Garden types 1 and 2) by proximal femoral nail antirotation (PFNA) in dementia patients. We studied retrospectively 19 patients with undisplaced femur neck fracture. All patients were over 70 years of age, walked independently with a cane or crutches and suffered moderate-to-severe dementia. Patients were treated with PFNA and followed-up for more than 2 years. Revision, loss of fixation, complications, and walking ability outcomes were measured. In walking-ability evaluation, patients showed an average decrease of just 0.2 points at the final follow-up. Walking ability was evaluated from before injury to 4 weeks after surgery and decreased by less than 0.5 points. Radiological bone union was achieved in 17 cases; the average time to bone union was 4.14 months (range, 2.5-7 months). Complications included non-union in two cases and femoral head avascular necrosis in one case of non-union. We found that for patients with osteoporotic bone tissues in their femoral heads or patients (e.g., those suffering dementia) for whom cooperating with medical workers for postoperative walking control or rehabilitation exercises is difficult, implanting a mechanically stable spiral blade for fixation of femoral neck fractures could facilitate walking after surgery.

  15. Fractures of the proximal femur: correlates of radiological evidence of osteoporosis

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Salil H.; Murphy, Kieran P. [Johns Hopkins School of Medicine, Radiology, Baltimore, Maryland (United States)

    2006-04-15

    Fractures of the proximal femur are common sequelae of osteoporosis, and are responsible for significant morbidity and mortality in elderly patients worldwide. Plain film radiographic assessment methods to assess for fracture risk may be of particular value. The authors present the results of biomechanical testing, radiographic imaging, and histologic exam of 20 embalmed human bone specimens, with implications for clinical correlation of radiologic findings. Authors assessed bone architecture using the Singh Index, using a blinded 3-rater system to reduce bias and measure intra-observer reliability. After loading to failure with ultimate tensile strength (UTS), bone specimens were assessed by fracture location type and by trabecular bone volume (TBV). Singh scoring was performed with Inter-Class Correlation of 0.80 (F=0.24, by ICC Portney Model 2). A statistically-significant difference among the UTS distributions was noted for UTS by Fracture Site (F=4.49, p=0.026, by ANOVA). No significant association of Singh Index with TBV, or TBV with UTS, was observed, although a trend toward greater UTS with higher Singh grade was observed. The authors propose that the Singh Index is a valuable and reliable indicator which may reflect structural integrity in trabecular bone. Fracture site along the femur is associated with tensile strength. The authors, in the light of these findings, address the promise and potential impact of prophylactic hip augmentation in populations at risk for femoral neck pathology. (orig.)

  16. [Bone Remodelling in the Proximal Femur after Uncemented Total Hip Arthroplasty in Patients with Osteoporosis].

    Science.gov (United States)

    Lacko, M; Schreierová, D; Čellár, R; Vaško, G

    2015-01-01

    The aim of the study was to investigate the involvement of osteoporosis during remodelling of the proximal femur after uncemented total hip arthroplasty (THA) and the effect of bisphospohonate treatment on these changes. Sixty evaluated patients with non-cemented THA were divided into three groups on the basis of pre-operative densitometric examinations. Group 1 (15 patients with osteoporosis) received a single dose of 5 mg zoledronic acid in infusion during the second post-operative week. Group 2 (15 patients with osteoporosis) were not treated by bisphospohonate. The patients of both groups took oral calcium and vitamin D medication. Group 3 (control) comprised 30 patients with normal bone density who did not take any osteoactive drugs. By measurement of bone mineral density (BMD) at 12 months after surgery, changes in periprosthetic bone of the proximal femur in 7 Gruen zones were recorded by densitometry. In addition, radiological findings on native X-ray images were assessed and the patients' clinical health status was rated by the Harris hip score. No significant differences in either the average age or the body mass index were found between the groups at the time of THA surgery. The mean BMD value in all assessed Gruen zones measured at the first post-operative week was higher in patients with normal bone density than in those with osteoporosis. The mean BMD value measured at 12 months decreased in all Gruen zones in comparison with the initial value, and this was found in all three groups. The lowest values were recorded in the untreated patients (group 2); in comparison with the patients who had normal bone density, the difference was statistically significant in Gruen zones 1, 2, 6 and 7. Although the patients with treated osteoporosis also showed lower BMD values, these were not statistically significant compared to group 3. The worst post-operative outcome in clinical health status was recorded in the patients with untreated osteoporosis. X

  17. Persistent wound drainage after tumor resection and endoprosthetic reconstruction of the proximal femur

    DEFF Research Database (Denmark)

    Hettwer, Werner H; Horstmann, Peter F; Grum-Schwensen, Tomas A

    2014-01-01

    PURPOSE: To examine the prevalence of prolonged wound drainage (PWD) after tumor resection and endoprosthetic reconstruction of the hip. METHODS: Retrospective review of 86 consecutive patients with metastatic bone disease, malignant hematologic bone disease or bone sarcoma, treated with tumor...... resection and subsequent endoprosthetic reconstruction of the proximal femur, between 2010 and 2012, in a single center. RESULTS: PWD for 7 days or more was observed in 41 cases (48%). The wounds only ceased oozing after a mean of 8.4 days, leading to prolonged administration of prophylactic antibiotics...... to be significantly more prevalent in patients undergoing tumor arthroplasty procedures of the hip. Given the potentially increased risk for periprosthetic joint infection (PJI), increased awareness, identification and implementation of adequate strategies for prevention and treatment of this avoidable complication...

  18. Pathological fractures of the proximal femur due to solitary bone cyst: classification, methods of treatment.

    Science.gov (United States)

    Miu, A

    2015-01-01

    Fractures are a very important issue in a child's orthopedic pathology. Neglected a good amount of time, being considered "not too serious", or "rare", having better and faster healing methods and not leaving sequels, like in the case of adults, a child's fractures remain an important chapter of traumatology in general. Because of the raising prevalence of child osteoarticular traumas, as well as new less invasive treatment methods, this theme is always to date. The paper analyzes particular cases of bone fractures that appeared due to minor traumas, on bones with a high brittleness, localized especially on the long bones. Although these fractures on a pathological bone can be seen at all levels of the human skeleton, this paper focuses on fractures located in the proximal third part of the femur. A group of children admitted in the Pediatric Orthopedic Department of "M.S. Curie" Hospital-Bucharest with this diagnostic, were analyzed between 2009 and 2013.

  19. Is endoprosthesis safer than internal fixation for metastatic disease of the proximal femur? A systematic review.

    Science.gov (United States)

    Di Martino, Alberto; Martinelli, Nicolò; Loppini, Mattia; Piccioli, Andrea; Denaro, Vincenzo

    2017-10-01

    Metastases to the proximal femur are usually managed surgically by tumor resection and reconstruction with an endoprosthesis, or by fixation with osteosynthesis. Still controversy remains regarding the most appropriate surgical treatment. We posed the following questions: (1) Is the frequency of surgical revision greater in patients treated with internal fixation than endoprosthetic reconstruction, and (2) Do complications that do not require surgery occur more frequently in patients treated with internal fixation rather than in those with endoprosthetic reconstruction? A systematic review was performed of those studies reporting on surgical revision and complication rates comparing the two surgical methods. Ten studies including 1107 patients met the inclusion criteria, three with high methodological quality, three intermediate, and four with lowquality, according to the STROBE guidelines. At present, prosthetic dislocation is the most common complication observed in patients managed by prosthesis replacement of the proximal femur, while loosening was the main cause of reoperation in the fixation group. Time to reintervention ranged from 3 to 11.6 months for the prosthetic replacement and from 7.8 to 22.3 months for the fixation group. Non surgical complications, (mainly dislocations and infections) were more commonly observed in patients operated on by prosthetic replacement. Implant related complications and surgery-related morbidity should be taken into account in the decision-making process for the surgical management of these patients. These data can improve the surgeon-patient communication and guide further studies on patients' survival and complications with respect to surgery. © 2017 Elsevier Ltd. All rights reserved.

  20. Identify fracture-critical regions inside the proximal femur using statistical parametric mapping.

    Science.gov (United States)

    Li, Wenjun; Kornak, John; Harris, Tamara; Keyak, Joyce; Li, Caixia; Lu, Ying; Cheng, Xiaoguang; Lang, Thomas

    2009-04-01

    We identified regions inside the proximal femur that are most strongly associated with hip fracture. Bone densitometry based on such fracture-critical regions showed improved power in discriminating fracture patients from controls. Hip fractures typically occur in lateral falls, with focal mechanical failure of the sub-volumes of tissue in which the applied stress exceeds the strength. In this study, we describe a new methodology to identify proximal femoral tissue elements with highest association with hip fracture. We hypothesize that bone mineral density (BMD) measured in such sub-volumes discriminates hip fracture risk better than BMD in standard anatomic regions such as the femoral neck and trochanter. We employed inter-subject registration to transform hip QCT images of 37 patients with hip fractures and 38 age-matched controls into a voxel-based statistical atlas. Within voxels, we performed t-tests between the two groups to identify the regions which differed most. We then randomly divided the 75 scans into a training set and a test set. From the training set, we derived a fracture-driven region of interest (ROI) based on association with fracture. In the test set, we measured BMD in this ROI to determine fracture discrimination efficacy using ROC analysis. Additionally, we compared the BMD distribution differences between the 29 patients with neck fractures and the 8 patients with trochanteric fractures. By evaluating fracture discrimination power based on ROC analysis, the fracture-driven ROI had an AUC (area under curve) of 0.92, while anatomic ROIs (including the entire proximal femur, the femoral neck, trochanter and their cortical and trabecular compartments) had AUC values between 0.78 and 0.87. We also observed that the neck fracture patients had lower BMD (p=0.014) in a small region near the femoral neck and the femoral head, and patients with trochanteric fractures had lower BMD in trochanteric regions such as in the internal calcar septum (p=0

  1. Site-specific advantages in skeletal geometry and strength at the proximal femur and forearm in young female gymnasts.

    Science.gov (United States)

    Dowthwaite, Jodi N; Rosenbaum, Paula F; Scerpella, Tamara A

    2012-05-01

    We evaluated site-specific skeletal adaptation to loading during growth, comparing radius (RAD) and femoral neck (FN) DXA scans in young female gymnasts (GYM) and non-gymnasts (NON). Subjects from an ongoing longitudinal study (8-26yr old) underwent annual DXA scans (proximal femur, forearm, total body) and anthropometry, completing maturity and physical activity questionnaires. This cross-sectional analysis used the most recent data meeting the following criteria: gynecological age ≤2.5yr post-menarche; and GYM annual mean gymnastic exposure ≥5.0h/wk in the prior year. Bone geometric and strength indices were derived from scans for 173 subjects (8-17yr old) via hip structural analysis (femoral narrow neck, NN) and similar radius formulae (1/3 and Ultradistal (UD)). Maturity was coded as M1 (Tanner I breast), M2 (pre-menarche, ≥Tanner II breast) or M3 (post-menarche). ANOVA and chi square compared descriptive data. Two factor ANCOVA adjusted for age, height, total body non-bone lean mass and percent body fat; significance was tested for main effects and interactions between gymnastic exposure and maturity. At the distal radius, GYM means were significantly greater than NON means for all variables (padvantages only in M1 and M3; for BMC and buckling ratio, M1 advantages were greatest); 2) 1/3 radius BMC, width, endosteal diameter, cortical cross-sectional area, and section modulus (GYM advantages primarily post-menarche); and 3) UD radius BMC and axial compressive strength (GYM advantages were larger with greater maturity, greatest post-menarche). Maturity-specific comparisons suggested site-specific skeletal adaptation to loading during growth, with greater advantages at the radius versus the proximal femur. At the radius, GYM advantages included greater bone width, cortical cross-sectional area and cortical thickness; in contrast, at the femoral neck, GYM bone tissue cross-sectional area and cortical thickness were greater, but bone width was narrower than

  2. Valgus sliding subtrochanteric osteotomy for neglected fractures of the proximal femur; surgical technique and a retrospective case series.

    Science.gov (United States)

    Gavaskar, Ashok S; Chowdary, Naveen T

    2013-03-15

    Conventional technique of valgus osteotomy of the proximal femur involves removal of a partial or full thickness lateral based wedge from the peritrochanteric region. The purpose of this article is to describe a novel technique of valgus subtrochanteric osteotomy for proximal femur nonunion. 11 patients with proximal femur nonunions {intracapsular fractures--7, extracapsular fractures--4} were treated using a new technique of sliding subtrochanteric osteotomy and DHS fixation. Outcomes analysed include radiological outcome in terms of improvement in Pauwel's angle, neck-shaft angle and evidence of radiological union at the nonunion site and osteotomy site. Other outcomes analysed include, measurement of limb length discrepancy and functional outcome assessment with Oxford hip score. Union at the nonunion site and the osteotomy site was achieved in all patients. There were significant improvements in the postoperative Pauwel's angle, neck shaft angle and Oxford hip score. Limb length discrepancy improved to less than 1 cm in all patients. There was no x ray evidence of avascular necrosis of the femoral head at one year follow-up. The sliding osteotomy technique is simple, does not need extensive pre operative planning or removal of bone from the proximal femur.

  3. Morphological analysis of the proximal femur by computed tomography in Japanese subjects

    Energy Technology Data Exchange (ETDEWEB)

    Hagiwara, Masashi [Chiba Univ. (Japan). School of Medicine

    1995-11-01

    In order to evaluate the morphological features of the proximal femur in the Japanese, 100 femora of normal Japanese subjects (normal group) and 60 femora of 43 Japanese patients with secondary osteoarthrosis of the hip (OA group) were analyzed using CT images. The scans for the dried bones (normal group) were done at a setting of 80 kV and 20 mA, for 2 sec duration. The scans were reconstructed using the soft tissue algorithm built into the GE-9800 scanner. The patient scans (OA group) were done at 120 kV and 170 mA also for 2 sec duration, and reconstructed using the same bone algorithm. The results were as follows: Thinning of the femoral cortex occurred in normal females over 60 years of age. The canal flare index at the proximal part of the femoral diaphysis was negatively correlated with the canal diameter at the isthmus. The index at the upper part was greater than that at the lower part. The two groups showed no statistical difference in this index. In the metaphysis, the canal flare index at the anterior portion was twice that at the posterior portion. In absolute terms, the OA group had a reduced flare or curve along the medial portion. In cross-section, the canal shape of the diaphysis was more elliptical in the OA group than in the normal group. The longitudinal axis of the canal was directed more sagittally in the OA group than in the normal group. (author).

  4. Development and testing of texture discriminators for the analysis of trabecular bone in proximal femur radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Huber, M. B.; Carballido-Gamio, J.; Fritscher, K.; Schubert, R.; Haenni, M.; Hengg, C.; Majumdar, S.; Link, T. M. [Department of Radiology and Biomedical Imaging, University of California, 400 Parnassus Avenue, San Francisco, California 94143 (United States); University of Health Sciences, Medical Informatics and Technology, 6060 Hall (Austria); AO Development Institute, 7270 Davos Platz (Switzerland); Medical University Innsbruck, 6020 Innsbruck (Austria); Department of Radiology and Biomedical Imaging, University of California, 400 Parnassus Avenue, San Francisco, California 94143 (United States)

    2009-11-15

    Purpose: Texture analysis of femur radiographs may serve as a potential low cost technique to predict osteoporotic fracture risk and has received considerable attention in the past years. A further application of this technique may be the measurement of the quality of specific bone compartments to provide useful information for treatment of bone fractures. Two challenges of texture analysis are the selection of the best suitable texture measure and reproducible placement of regions of interest (ROIs). The goal of this in vitro study was to automatically place ROIs in radiographs of proximal femur specimens and to calculate correlations between various different texture analysis methods and the femurs' anchorage strength. Methods: Radiographs were obtained from 14 femoral specimens and bone mineral density (BMD) was measured in the femoral neck. Biomechanical testing was performed to assess the anchorage strength in terms of failure load, breakaway torque, and number of cycles. Images were segmented using a framework that is based on the usage of level sets and statistical in-shape models. Five ROIs were automatically placed in the head, upper and lower neck, trochanteric, and shaft compartment in an atlas subject. All other subjects were registered rigidly, affinely, and nonlinearly, and the resulting transformation was used to map the five ROIs onto the individual femora. Results: In each ROI, texture features were extracted using gray level co-occurence matrices (GLCM), third-order GLCM, morphological gradients (MGs), Minkowski dimensions (MDs), Minkowski functionals (MFs), Gaussian Markov random fields, and scaling index method (SIM). Coefficients of determination for each texture feature with parameters of anchorage strength were computed. In a stepwise multiregression analysis, the most predictive parameters were identified in different models. Texture features were highly correlated with anchorage strength estimated by the failure load of up to R{sup 2

  5. Does a traction-internal rotation radiograph help to better evaluate fractures of the proximal femur?

    Science.gov (United States)

    Koval, Kenneth J; Oh, Chong K; Egol, Kenneth A

    2008-01-01

    The standard radiographic series for evaluation of a suspected hip fracture in most centers includes an anteroposterior (AP) radiograph of the pelvis, as well AP and cross-table lateral views of the hip. The natural femoral neck anteversion, as well as the fracture deformity, however, may make accurate fracture classification difficult. We have noted that inexperienced physicians sometimes misclassify hip fractures based on the initial radiographic series, which may lead to errors both in surgical planning and implant choice. At our institution, we routinely obtain a physician-assisted traction-internal rotation radiograph of the affected hip in all fractures of the proximal femur. The purpose of the current study was to examine the usefulness of the traction-internal rotation radiograph for the classification of hip fractures by junior residents in our department. Forty-seven sets of complete radiographs (AP pelvis, AP hip, cross-table lateral, traction- internal rotation views) of patients who sustained a proximal femur fracture were identified. Fifteen first year orthopaedic residents (PGY2) individually reviewed the cases and classified them as one of six possible choices: 1. nondisplaced femoral neck fracture, 2. displaced femoral neck fracture, 3. stable intertrochanteric fracture, 4. unstable intertrochanteric fracture, 5. intertrochanteric fracture with subtrochanteric extension, or 6. subtrochanteric fracture. Each fracture case was classified after first reviewing the standard hip series (AP pelvis, AP hip, and cross-table lateral). A traction-internal rotation radiograph was then added to each case, and any changes in the initial classification were noted. The resident's classification was then compared with those of the senior investigators (KJK, KAE), who used all four views for classification. Reviewing a traction-internal rotation radiograph led to a statistically significant increase in agreement between the resident and senior investigators

  6. Associations of Age, BMI, and Years of Menstruation with Proximal Femur Strength in Chinese Postmenopausal Women: A Cross-Sectional Study.

    Science.gov (United States)

    Kang, Huili; Chen, Yu-Ming; Han, Guiyuan; Huang, Hua; Chen, Wei-Qing; Wang, Xidan; Zhu, Ying-Ying; Xiao, Su-Mei

    2016-01-23

    This study aimed to elucidate the associations of age, BMI, and years of menstruation with proximal femur strength in Chinese postmenopausal women, which may improve the prediction of hip fracture risk. A cross-sectional study was conducted in 1322 Chinese postmenopausal women recruited from communities. DXA images were used to generate bone mineral density (BMD) and geometric parameters, including cross-sectional area (CSA), outer diameter (OD), cortical thickness (CT), section modulus (SM), buckling ratio (BR) at the narrow neck (NN), intertrochanter (IT), and femoral shaft (FS). Relationships of age, BMI, and years of menstruation with bone phenotypes were analyzed with the adjustment of height, age at menarche, total daily physical activity, education, smoking status, calcium tablet intake, etc. Age was associated with lower BMD, CSA, CT, SM, and higher BR (p menstruation had the positive relationships with proximal femur strength (p menstruation were 0.14%-1.34%, 0.20%-2.70%, and 0.16%-0.98%, respectively. These results supported that bone strength deteriorated with aging and enhanced with higher BMI and longer time of years of menstruation in Chinese postmenopausal women.

  7. Extensively coated revision stems in proximally deficient femur: Early results in 15 patients

    Directory of Open Access Journals (Sweden)

    Marya SKS

    2008-01-01

    intraoperative severe comminuted fracture extending into the supracondylar region while hammering in the stem. Post cerclage wiring, she was put on a long knee brace and her mobilization was delayed to 12 weeks. Conclusions: The extensively coated cementless ( ′Solution™′ femoral stem provides a reasonable ′solution′ to the deficient femur in hip revision. The proximal femoral deficiences can be relatively easily bypassed and distal fixation can be achieved with this stem. Extreme care needs to be taken to avoid fractures and penetration of the femoral shaft, which can, however, be managed by cerclage wiring. Principles of a successful outcome include preservation of the functional continuity of the abduction apparatus, care to recognize and prevent distal extension of fracture while inserting the stem (preemptive cerclage wiring and supervised rehabilitation.

  8. The Outcome in Early Cases of Treatment of Subtrochanteric Fractures with Proximal Femur Locking Compression Plate

    Directory of Open Access Journals (Sweden)

    U Gunadham

    2014-07-01

    Full Text Available The objective of this study was to evaluate the outcome in early treatment of subtrochanteric fractures with proximal femur locking compression plate (PF-LCP.The patients included in this study were those with subtrochanteric fractures (AO type 32A-C treated with PF-LCP (Synthes between Jan 2009 and Jun 2011. The patient characteristics and details of clinical conditions were obtained from records. Clinical and radiographic follow-ups were done at one, two, four and 6 months intervals, and at one year. The primary outcome studied included fracture union and functional ambulatory status. Twenty-six patients were included in the study, 19 of whom were male with a mean age of 42.4 years. Fourteen patients (53.9% had sustained AO type 32B fractures, the majority in motor vehicle accidents. Twenty-two fractures (84.6% achieved union, while sixpatients (23.1% had complications such as broken plate, varus collapse, and broken screw. Four patients (15.4% underwent a second operation. At the end of the follow-ups, 25 patients (96.2% were community ambulators. We conclude that PF-LCP is an effective alternative treatment for subtrochanteric fractures when properly performed.

  9. Aneurysmal Bone Cyst of the Proximal Femur and Its Management - A Case Report.

    Science.gov (United States)

    Kapoor, Chirag; Shah, Malkesh; Soni, Rishit; Patwa, Jagdish; Merh, Aditya; Golwala, Paresh

    2017-01-23

    Aneurysmal bone cyst (ABC) is a benign, expansile, non-neoplastic lesion of the bone, characterized by channels of blood and spaces that are separated by fibrous septae. Giant ABC is an uncommon condition and can be difficult to handle because of the destructive effect of the cyst on the bones and the compressive effect on the nearby structures, especially in weight-bearing bones of the body. We report a case of a giant aneurysmal bone cyst in the proximal femur of a six-year-old child, which was treated with a sclerosing agent and ender's nail fixation first. There was recurrence after 13 months. It was then curetted out extensively, the cavity was filled with bone graft, and fixation with a dynamic hip screw (DHS) was done. At 19 months follow-up, the lesion had subsided and patient was walking pain-free without any deformity. We suggest this method of treatment to be worthwhile for ABC at this site and at this age.

  10. Sensitivity and specificity of CT- and MRI-scanning in evaluation of occult fracture of the proximal femur

    DEFF Research Database (Denmark)

    Haubro, M; Stougaard, C; Torfing, T

    2015-01-01

    and a resident in orthopaedic surgery. Sensitivity and specificity were estimated with MRI as the golden standard. Kappa value was used to assess level of agreement in both MRI and CT finding. RESULTS: 15 fractures of the proximal femur were found (7 intertrochanteric-, 3 femoral neck and 5 fractures......OBJECTIVE: To estimate sensitivity and specificity of CT and MRI examinations in patients with fractures of the proximal femur. To determine the interobserver agreement of the modalities among a senior consulting radiologist, a resident in radiology and a resident in orthopaedics surgery. MATERIALS...... AND METHODS: 67 patients (27 males, 40 females, mean age 80.5) seen in the emergency room with hip pain after fall, inability to stand and a primary X-ray without fracture were evaluated with both CT and MRI. The images were analysed by a senior consulting musculoskeletal radiologist, a resident in radiology...

  11. Deformity of the proximal end of the femur following open reduction for developmental dislocation of the hip

    OpenAIRE

    Ikegami, Koichi; Nakatsuka, Yoichi; Akazawa, Hirofumi; Mitani, Shigeru; Inoue, Hajime

    1997-01-01

    We studied deformity of the proximal end of the femur following open reduction using the wide exposure method for developmental dislocation of the hip. We reviewed radiographs of 22 children with unilateral dislocation of the hip who had undergone open reduction between one and three years of age. Ages at final examination ranged from 14 to 21 years. None of the patients in this study had undergone any additional surgery. Avascular necrosis of the femoral head was not observed in any patients...

  12. Bone mineral density of the proximal femur after hip resurfacing arthroplasty: 1-year follow-up study

    Directory of Open Access Journals (Sweden)

    Anttila Esa

    2011-05-01

    Full Text Available Abstract Background Hip resurfacing arthroplasty (HRA is considered a bone-preserving procedure and may eliminate proximal femoral stress shielding and osteolysis. However, in addition to implant-related stress-shielding factors, various patient-related factors may also have an effect on bone mineral density (BMD of the proximal femur in patients with HRA. Thus, we studied the effects of stem-neck angle, demographic variables, and physical functioning on the BMD of the proximal femur in a one-year follow-up. Methods Thirty three patients (9 females and 24 males with a mean (SD age of 55 (9 years were included in the study. BMD was measured two days and 3, 6, and 12 months postoperatively and 10 regions of interest (ROI were used. Stem-neck angle was analyzed from anteroposterior radiographs. Results Three months postoperatively, BMD decreased in six out of 10 regions of interest (ROI on the side operated on and in one ROI on the control side (p Conclusions After an early drop, the BMD of the upper femur was restored and even exceeded the preoperative level at one year follow-up. From a clinical standpoint, the changes in BMD in these HRA patients could not be explained by stem-neck angle or patient related factors.

  13. Epidemiology of fractures of the proximal third of the femur in elderly patients ☆

    Directory of Open Access Journals (Sweden)

    Daniel Daniachi

    2015-08-01

    Full Text Available ABSTRACTOBJECTIVE: This was an epidemiological study on fractures of the proximal third of the femur in elderly patients who were treated at a teaching hospital in the central region of São Paulo. METHODS: The subjects were patients over the age of 60 years who were attended over a 1-year period. A questionnaire seeking basic sociodemographic data and information on comorbidities presented and medications used was drawn up. The circumstances of the fractures and their characteristics, the treatment instituted and the intra-hospital mortality rate were evaluated. RESULTS: The 113 patients included in the study presented a mean age of 79 years. The ratio between the sexes was three women to each man. Only 30.4% of the patients reported having osteoporosis and only 0.9% had had treatment for the disease. Low-energy trauma was the cause of 92.9% of the fractures. Femoral neck fractures accounted for 42.5% of the fractures and trochanteric fractures, 57.5%. Five patients did not undergo operations; 39 underwent joint replacement; and 69 underwent osteosynthesis. The mean length of hospital stay was 13.5 days and the mean length of waiting time until surgery was 7 days. The intra-hospital mortality rate was 7.1%. CONCLUSION: The patients attended at this institution presented an epidemiological profile similar to what is found in the Brazilian literature. Chronic kidney failure is a significant factor with regard to intra-hospital mortality. Preventive measures such as early diagnosis and treatment of osteoporosis and regular physical activity practices were not implemented.

  14. Shape of growth plate of proximal femur in children and its significance in the aetiology of slipped capital femoral epiphysis.

    Science.gov (United States)

    Kandzierski, Grzegorz; Matuszewski, Lukasz; Wójcik, Anna

    2012-12-01

    The main objective of the study was to present the influence of the morphological shape of the proximal femoral growth plate in children as one of the risk factors for the incidence of slipped capital femoral epiphysis (SCFE) in adolescents. This research is based on the X-ray, computed tomography (CT) and magnetic resonance imaging (MRI) data obtained for 100 children three to 13 years old, all treated at the Children's Orthopaedic Clinic and Rehabilitation Department and Department of Radiology Medical University of Lublin between 2005 and 2009. We took into account 83 children with healthy hip joints and 17 children with SCFE. We also performed morphological analysis of the shape of the proximal femoral growth plate together with X-ray, CT and MRI examinations of the proximal ends of cadaver femurs for two children aged six and 13. In the final findings we present an analysis of the shape of the proximal femoral growth plate in children between the third and 13th years of life and consider a correlation between the shape of the proximal femoral growth plate and its influence on the incidence of SCFE in adolescents. The change of shape of the proximal femoral growth plate from pleated to more spherical is one of the risk factors for the incidence of SCFE in children ten years old and older.

  15. Hemiarthroplasties in young patients with osteonecrosis or a tumour of the proximal femur; an observational cohort study.

    Science.gov (United States)

    van Egmond, Pim W; Taminiau, Antonie H M; van der Heide, Huub J L

    2013-01-17

    The failure scenario in total hip arthroplasty (THA), in younger patients, is dependent on the fixation and wear of the acetabular component. In selected cases, where endoprosthetic replacement of the femoral head is unavoidable for limb salvage or functional recovery, hemiarthroplasty can be chosen as an alternative. The purpose of this study is to evaluate hemiarthroplasty as treatment strategy for young patients with osteonecrosis or a tumour of the proximal femur. Between 1985 and 2008, 42 hemiarthroplasties (unipolar and bipolar) were performed in patients younger than 65 years with osteonecrosis (n=13) or a tumour of the proximal femur (n=29). All patients were seen at yearly follow-up examination and evaluated. Revision or conversion to a THA was regarded as a failure of the implant. A Kaplan Meier analysis was performed. To determine significant differences between categorical groups, the Pearson chi-square test was used. In numerical groups the independent T-test and One-way ANOVA were used. After a mean follow-up of 7.1 years, failure of the hemiarthroplasty occurred 6 times. The Kaplan Meier survival analysis with conversion to THA or revision as endpoint of the bipolar hemiarthroplasties (n=38) shows a 96% survival at 15, and 60% at 20 years. In the unipolar type (n=4) we found a conversion rate of 50% within 3 years. Bipolar hemiarthroplasty is a reasonable alternative in a young patient with osteonecrosis or a tumour of the proximal femur as indication. Because of the high conversion rate after unipolar hemiarthroplasties, we would not recommend this type of prosthesis in the young patient.

  16. Sex specific association of physical activity on proximal femur BMD in 9 to 10 year-old children.

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    Graça Cardadeiro

    Full Text Available The results of physical activity (PA intervention studies suggest that adaptation to mechanical loading at the femoral neck (FN is weaker in girls than in boys. Less is known about gender differences associated with non-targeted PA levels at the FN or other clinically relevant regions of the proximal femur. Understanding sex-specific relationships between proximal femur sensitivity and mechanical loading during non-targeted PA is critical to planning appropriate public health interventions. We examined sex-specific associations between non-target PA and bone mineral density (BMD of three sub-regions of the proximal femur in pre- and early-pubertal boys and girls. BMD at the FN, trochanter (TR and intertrochanter (IT regions, and lean mass of the whole body were assessed using dual-energy x-ray absorptiometry in 161 girls (age: 9.7±0.3 yrs and 164 boys (age: 9.7±0.3 yrs. PA was measured using accelerometry. Multiple linear regression analyses (adjusted for body height, total lean mass and pubertal status revealed that vigorous PA explained 3-5% of the variability in BMD at all three sub-regions in boys. In girls, vigorous PA explained 4% of the variability in IT BMD and 6% in TR BMD. PA did not contribute to the variance in FN BMD in girls. An additional 10 minutes per day of vigorous PA would be expected to result in a ∼1% higher FN, TR, and IT BMD in boys (p<0.05 and a ∼2% higher IT and TR BMD in girls. In conclusion, vigorous PA can be expected to contribute positively to bone health outcomes for boys and girls. However, the association of vigorous PA to sub-regions of the proximal femur varies by sex, such that girlś associations are heterogeneous and the lowest at the FN, but stronger at the TR and the IT, when compared to boys.

  17. The risk assessment of pathological fracture in the proximal femur using a CT-based finite element method.

    Science.gov (United States)

    Kawabata, Yusuke; Matsuo, Kosuke; Nezu, Yutaka; Kamiishi, Takayuki; Inaba, Yutaka; Saito, Tomoyuki

    2017-09-01

    Patients who have lytic bone lesions in their proximal femurs are at risk for pathological fracture. Lesions with high fracture risk are surgically treated using prophylactic osteosynthesis, whereas low-risk lesions are treated conservatively. However, it is difficult to discriminate between high- and low-risk lesions based on clinical and radiographic findings. The computed tomography (CT)-based finite element (FE) models are useful for predicting the fracture load on proximal femoral lytic lesions. FE models were constructed from the quantitative CT scans of the femurs using software that created individual bone shapes and density distributions. Three independent observers measured the lesion size, Mirels' score, and thickness of the proximal femur along the horizontal plane. The predictive risk values of the proximal femur measured using the CT-based FE analysis were statistically compared. The patients were divided into two groups (high and low risk). The mean fracture load was significantly higher in the high-risk group than in the low-risk group (5395 ± 525 N, 2622 ± 364 N, respectively, p = 0.0003). No significant differences in age, body weight, lesion size or Mirels' score were observed between groups. However, the thickness of the medial cortex in the high-risk group according to the FE analysis was significantly thinner than that in the low-risk group. Furthermore, the medial cortex thickness was positively correlated with the predicted fracture load. An optimal cut-off value of 3.67 mm for the thickness of the inner cortex resulted in 100% sensitivity and 75.1% specificity values for classifying the patients based on their fracture risk. Our findings indicate that the FE method is useful for the prediction of the pathological fracture. This method shows a versatile potential for the prediction of pathological fracture and might aid in judging the optimal treatment to prevent fracture. Copyright © 2017 The Japanese Orthopaedic Association

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

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

    2014-10-15

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

  19. A Prospective Study to Evaluate the Management of Sub-trochanteric Femur Fractures with Long Proximal Femoral Nail

    Directory of Open Access Journals (Sweden)

    Kumar M

    2017-11-01

    Full Text Available INTRODUCTION: Sub-trochanteric fractures of the femur remains one of the most challenging fractures faced by orthopaedic surgeons. This study was done to analyse the management and complications of sub-trochanteric fractures using long proximal femoral nail (PFN. MATERIALS AND METHODS: This was a prospective study of 50 patients with sub-trochanteric fractures of femur who were treated with long PFN at a tertiary care center from July 2012 to June 2016. The fractures were classified according to Seinsheimer classification. All patients were assessed functionally by Harris Hip Score. RESULTS: Average duration of union was 17.08 weeks (range 13 to 32 weeks, union was achieved in 92% cases. Closed reduction was achieved in 68% cases and open reduction was required in 32% cases. Various intraoperative complications were seen in 12% and delayed complications in 26% of cases. Good anatomical results were achieved in 86% of cases and 14% were fair. As per Harris Hip score, excellent results were noted in 28% cases, good in 56% cases and fair in 16% cases. CONCLUSION: The long PFN is a reliable implant for sub-trochanteric femur fractures, with high rate of bone union and minimal soft tissue damage. Intramedullary fixation has biological and biomechanical advantages, but the surgery is technically demanding.

  20. Changes of the bone mineral density in proximal femur following total hip resurfacing arthroplasty in osteonecrosis of femoral head.

    Science.gov (United States)

    Lian, Yong-yun; Pei, Fu-xing; Yoo, Myung-chul; Cheng, Jing-qiu; Fatou, Camara-yagouba

    2008-04-01

    Total hip resurfacing arthroplasty (THRA) is being performed with increasing frequency for osteonecrosis of femoral head (ONFH). To evaluate femoral bone remodeling in ONFH after THRA and determine the impact of stem-neck angle (SNA) of inserted femoral component on bone remodeling, we monitored the changes in BMD in proximal femur in 23 patients with ONFH after surgery. Patients were divided into group A (SNA >or= 5 degrees ) and group B (SNA < 5 degrees ). The BMD was measured in seven Gruen zones and two neck zones using dual-energy X-ray absorptiometry preoperatively, then at 3, 6, 12, and 24 months after surgery. At all ROIs, the BMD decreased significantly by 3 months postoperatively. The BMD ceased to decrease and reversed by 6 months. The BMD in neck increased significantly in group A, compared with group B at 24 months. The BMD increased 2% at ROI1 at 24 months in both groups, and at ROI7, the BMD in group A reversed to baseline value by 6 months and increased 5.81% at 24 months. These findings implied that the bone stock of proximal femur in ONFH can be well reserved after total hip resurfacing arthroplasty with valgus positioning of the femoral component.

  1. Uncommon Floating Knee in a Teenager: A Case Report of Ipsilateral Physeal Fractures in Distal Femur and Proximal Tibia.

    Science.gov (United States)

    Othman, Youssef; Hassini, Lassaad; Fekih, Aymen; Aloui, Issam; Abid, Abderrazek

    2017-01-01

    The concomitance of ipsilateral physeal fractures of the distal femur and the proximal tibia is an extremely scarce entity. It is conceptually similar to floating knee in pediatric population. One case with this injury is reported in a 16-year-old teenager. He was treated surgically by close reduction and internal fixation. The diagnosis of the tibial fracture was initially missed and the fracture was seen on the post-operative radiographs. Orthopedic treatment was made for this injury. 2 years after, no angular deformity neither shortening of the limb were found. These rare injuries could have serious immediate and remote complication with a considerable functional impact. The diagnosis of proximal tibia physeal fracture could be missed in the context of a concomitant more impressive distal femur fracture. The possibility of a combination of these two injuries should then be kept in mind. Anatomic reduction should be made as soon as possible using a gentle technique and attention should be given to the diagnosis of the neurovascular complications.

  2. The relationship between osteoarthritis of the knee and bone mineral density of proximal femur: a cross-sectional study from a Korean population in women.

    Science.gov (United States)

    Im, Gun-Il; Kwon, Oh-Jin; Kim, Chang Hee

    2014-12-01

    The relationship between osteoarthritis (OA) and osteoporosis (OP) is complicated and it may differ according to the site or stage of disease. The purpose of this cross-sectional study is to examine the relationship between the severity of radiological knee OA and the degree of OP in the ipsilateral proximal femur as denoted by bone mineral density (BMD) in a Korean population, especially among women. One hundred ninety-five female patients who had knee pain and radiological knee OA were investigated with respect to the relationship of knee OA severity with BMD. The BMD of the proximal femur and spine was measured by dual energy X-ray absorptiometry, and the severity of knee OA was evaluated based on Kellgren-Lawrence (K-L) radiographic criteria, joint space narrowing (JSN) and mechanical axis of knee alignment. Partial correlation analysis and ANCOVA adjusted for confounding factors (age and body mass index) were performed to assess the relationship. There was a statistically significant relationship between the BMD of the proximal femur and JSN, and the BMD of the proximal femur was positively associated with increased joint space width. There was a lack of association between the spine BMD and JSN. The BMD of the proximal femur was also significantly lower in patients who had a higher K-L grade. The radiographic finding of severe OA in the knee is associated with decreased BMD of the ipsilateral proximal femur including the femoral neck, trochanter, intertrochanter, and region of the entire hip (neck, trochanter, and Ward's triangle).

  3. Bone mineral and stiffness loss at the distal femur and proximal tibia in acute spinal cord injury.

    Science.gov (United States)

    Edwards, W B; Schnitzer, T J; Troy, K L

    2014-03-01

    Computed tomography and finite element modeling were used to assess bone mineral and stiffness loss at the knee following acute spinal cord injury (SCI). Marked bone mineral loss was observed from a combination of trabecular and endocortical resorption. Reductions in stiffness were 2-fold greater than reductions in integral bone mineral. SCI is associated with a rapid loss of bone mineral and an increased rate of fragility fracture. The large majority of these fractures occur around regions of the knee. Our purpose was to quantify changes to bone mineral, geometry, strength indices, and stiffness at the distal femur and proximal tibia in acute SCI. Quantitative computed tomography (QCT) and patient-specific finite element analysis were performed on 13 subjects with acute SCI at serial time points separated by a mean of 3.5 months (range 2.6-4.8 months). Changes in bone mineral content (BMC) and volumetric bone mineral density (vBMD) were quantified for integral, trabecular, and cortical bone at epiphyseal, metaphyseal, and diaphyseal regions of the distal femur and proximal tibia. Changes in bone volumes, cross-sectional areas, strength indices and stiffness were also determined. Bone mineral loss was similar in magnitude at the distal femur and proximal tibia. Reductions were most pronounced at epiphyseal regions, ranging from 3.0 % to 3.6 % per month for integral BMC (p < 0.001) and from 2.8 % to 3.4 % per month (p < 0.001) for integral vBMC. Trabecular BMC decreased by 3.1-4.4 %/month (p < 0.001) and trabecular vBMD by 2.7-4.7 %/month (p < 0.001). A 3.8-5.4 %/month reduction was observed for cortical BMC (p < 0.001); the reduction in cortical vBMD was noticeably lower (0.6-0.8 %/month; p ≤ 0.01). The cortical bone loss occurred primarily through endosteal resorption, and reductions in strength indices and stiffness were some 2-fold greater than reductions in integral bone mineral. These findings highlight the need for therapeutic

  4. Recurrent Proximal Femur Fractures in a Teenager With Osteogenesis Imperfecta on Continuous Bisphosphonate Therapy: Are We Overtreating?

    Science.gov (United States)

    Vasanwala, Rashida F; Sanghrajka, Anish; Bishop, Nicholas J; Högler, Wolfgang

    2016-07-01

    Long-term bisphosphonate (BP) therapy in adults with osteoporosis is associated with atypical femoral fractures, caused by increased material bone density and prolonged suppression of bone remodeling which may reduce fracture toughness. In children with osteogenesis imperfecta (OI), long-term intravenous BP therapy improves bone structure and mass without further increasing the already hypermineralized bone matrix, and is generally regarded as safe. Here we report a teenage girl with OI type IV, who was started on cyclical intravenous pamidronate therapy at age 6 years because of recurrent fractures. Transiliac bone biopsy revealed classical structural features of OI but unusually low bone resorption surfaces. She made substantial improvements in functional ability, bone mass, and fracture rate. However, after 5 years of pamidronate therapy she started to develop recurrent, bilateral, nontraumatic, and proximal femur fractures, which satisfied the case definition for atypical femur fractures. Some fractures were preceded by periosteal reactions and prodromal pain. Pamidronate was discontinued after 7 years of therapy, following which she sustained two further nontraumatic femur fractures, and continued to show delayed tibial osteotomy healing. Despite rodding surgery, and very much in contrast to her affected, untreated, and normally mobile mother, she remains wheelchair-dependent. The case of this girl raises questions about the long-term safety of BP therapy in some children, in particular about the risk of oversuppressed bone remodeling with the potential for microcrack accumulation, delayed healing, and increased stiffness. The principal concern is whether there is point at which benefit from BP therapy could turn into harm, where fracture risk increases again. This case should stimulate debate whether current adult atypical femoral fracture guidance should apply to children, and whether low-frequency, low-dose cyclical, intermittent, or oral treatment

  5. Individual-specific multi-scale finite element simulation of cortical bone of human proximal femur

    Science.gov (United States)

    Ascenzi, Maria-Grazia; Kawas, Neal P.; Lutz, Andre; Kardas, Dieter; Nackenhorst, Udo; Keyak, Joyce H.

    2013-07-01

    We present an innovative method to perform multi-scale finite element analyses of the cortical component of the femur using the individual's (1) computed tomography scan; and (2) a bone specimen obtained in conjunction with orthopedic surgery. The method enables study of micro-structural characteristics regulating strains and stresses under physiological loading conditions. The analysis of the micro-structural scenarios that cause variation of strain and stress is the first step in understanding the elevated strains and stresses in bone tissue, which are indicative of higher likelihood of micro-crack formation in bone, implicated in consequent remodeling or macroscopic bone fracture. Evidence that micro-structure varies with clinical history and contributes in significant, but poorly understood, ways to bone function, motivates the method's development, as does need for software tools to investigate relationships between macroscopic loading and micro-structure. Three applications - varying region of interest, bone mineral density, and orientation of collagen type I, illustrate the method. We show, in comparison between physiological loading and simple compression of a patient's femur, that strains computed at the multi-scale model's micro-level: (i) differ; and (ii) depend on local collagen-apatite orientation and degree of calcification. Our findings confirm the strain concentration role of osteocyte lacunae, important for mechano-transduction. We hypothesize occurrence of micro-crack formation, leading either to remodeling or macroscopic fracture, when the computed strains exceed the elastic range observed in micro-structural testing.

  6. A MULTIDISCIPLINARY APPROACH IN THE TREATMENT OF FRACTURES OF THE PROXIMAL FEMUR ON THE BACKGROUND OF SENILE OSTEOPOROSIS

    Directory of Open Access Journals (Sweden)

    N. V. Zagorodniy

    2016-01-01

    Full Text Available The article presents a review of published data on the problem of osteoporosis in patients older than 75 years who have had fractures of the proximal femur. We used descriptive and analytical methods. Search publications have done in accessible to free search databases. Based on our analysis, it was found: the majority of researchers in Russia and abroad are united in the opinion that this issue requires a multidisciplinary approach; surgical treatment should be initiated as early as possible after the onset of fracture, before the complications from side of the internal organs; patients with fractures on the background of senile osteoporosis should receive drugs that affect to the quantitative and qualitative components of bone.

  7. [Our view on the problem of treating patients with fractures of the proximal segment of the femur].

    Science.gov (United States)

    Ternovoi, N K; Samokhin, A V; Grebennikov, K A

    2001-01-01

    The purpose of this study is to elucidate and analyze causes of difficulties encountered in dealing with fractures of the proximal segment of the femur and to set out our idea of solving these problems. An analysis is performed of classifications, an assessment is given of studying the adequate choice of a treatment modality, an attempt is made at formulating a doctrine of delivering qualified and specialized emergency medical service to those persons having been disabled for work, which could take account of all aspects of the injury under study. Indications for hemiarthroplasty are outlined, with the policy of primary sparing the joint elements by atraumatic osteosynthesis techniques being chosen in preference to any other policy.

  8. Influence of Lateral Muscle Loading in the Proximal Femur after Fracture Stabilization with a Trochanteric Gamma Nail (TGN)

    Science.gov (United States)

    Sitthiseripratip, Kriskrai; Mahaisavariya, Banchong; Suwanprateeb, Jintamai; Bohez, Erik; Vander Sloten, Jos

    The purpose of this study was to investigate the influence of lateral muscle loading on the stress/strain distributions of the trochanteric Gamma nail (TGN) fixation within the healed, trochanteric and subtrochanteric femoral fractures by means of a finite element method. The effect of three muscle groups, the abductors (ABD), the vastus lateralis (VL) and the iliotibial band (ITB), were investigated. The analytical results showed that addition of lateral muscle forces, iliotibial band and vastus lateralis, produced compensation of forces and reduction of bending moments in the bone and in the trochanteric Gamma nail especially in the lateral aspect. The iliotibial band produced a higher impact as compared to the vastus lateralis. Therefore in the finite element analysis of the proximal femur with the trochanteric Gamma nail fracture fixation should include the lateral muscle forces to simulate load condition with maximal physiological relevance to the closed nailing technique.

  9. Study of the interactions between proximal femur 3d bone shape, cartilage health, and biomechanics in patients with hip Osteoarthritis.

    Science.gov (United States)

    Pedoia, Valentina; Samaan, Michael A; Inamdar, Gaurav; Gallo, Matthew C; Souza, Richard B; Majumdar, Sharmila

    2017-07-08

    In this study quantitative MRI and gait analysis were used to investigate the relationships between proximal femur 3D bone shape, cartilage morphology, cartilage biochemical composition, and joint biomechanics in subject with hip Osteoarthritis (OA). Eighty subjects underwent unilateral hip MR-imaging: T1ρ and T2 relaxation times were extracted through voxel based relaxometry and bone shape was assessed with 3D MRI-based statistical shape modeling. In addition, 3D gait analysis was performed in seventy-six of the studied subjects. Associations between shape, cartilage lesion presence, severity, and cartilage T1ρ and T2 were analyzed with linear regression and statistical parametric mapping. An ad hoc analysis was performed to investigate biomechanics and shape associations. Our results showed that subjects with a higher neck shaft angle in the coronal plane (higher mode 1, coxa valga), thicker femoral neck and a less spherical femoral head (higher mode 5, pistol grip) exhibited more severe acetabular and femoral cartilage abnormalities, showing different interactions with demographics factors. Subjects with coxa valga also demonstrated a prolongation of T1ρ and T2. Subjects with pistol grip deformity exhibited reduced hip internal rotation angles and subjects with coxa valga exhibited higher peak hip adduction moment and moment impulse. The results of this study establish a clear relationship between 3D proximal femur shape variations and markers of hip joint degeneration-morphological, compositional, well as insight on the possible interactions with demographics and biomechanics, suggesting that 3D MRI-based bone shape maybe a promising biomarker of early hip joint degeneration. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  10. Individual-specific multi-scale finite element simulation of cortical bone of human proximal femur

    Energy Technology Data Exchange (ETDEWEB)

    Ascenzi, Maria-Grazia, E-mail: mgascenzi@mednet.ucla.edu [UCLA/Orthopaedic Hospital, Department of Orthopaedic Surgery, Rehabilitation Bldg, Room 22-69, 1000 Veteran Avenue, University of California, Los Angeles, CA 90095 (United States); Kawas, Neal P., E-mail: nealkawas@ucla.edu [UCLA/Orthopaedic Hospital, Department of Orthopaedic Surgery, Rehabilitation Bldg, Room 22-69, 1000 Veteran Avenue, University of California, Los Angeles, CA 90095 (United States); Lutz, Andre, E-mail: andre.lutz@hotmail.de [Institute of Biomechanics and Numerical Mechanics, Leibniz University Hannover, 30167 Hannover (Germany); Kardas, Dieter, E-mail: kardas@ibnm.uni-hannover.de [ContiTech Vibration Control, Jaedekamp 30 None, 30419 Hannover (Germany); Nackenhorst, Udo, E-mail: nackenhorst@ibnm.uni-hannover.de [Institute of Biomechanics and Numerical Mechanics, Leibniz University Hannover, 30167 Hannover (Germany); Keyak, Joyce H., E-mail: jhkeyak@uci.edu [Department of Radiological Sciences, Medical Sciences I, Bldg 811, Room B140, University of California, Irvine, CA 92697-5000 (United States)

    2013-07-01

    We present an innovative method to perform multi-scale finite element analyses of the cortical component of the femur using the individual’s (1) computed tomography scan; and (2) a bone specimen obtained in conjunction with orthopedic surgery. The method enables study of micro-structural characteristics regulating strains and stresses under physiological loading conditions. The analysis of the micro-structural scenarios that cause variation of strain and stress is the first step in understanding the elevated strains and stresses in bone tissue, which are indicative of higher likelihood of micro-crack formation in bone, implicated in consequent remodeling or macroscopic bone fracture. Evidence that micro-structure varies with clinical history and contributes in significant, but poorly understood, ways to bone function, motivates the method’s development, as does need for software tools to investigate relationships between macroscopic loading and micro-structure. Three applications – varying region of interest, bone mineral density, and orientation of collagen type I, illustrate the method. We show, in comparison between physiological loading and simple compression of a patient’s femur, that strains computed at the multi-scale model’s micro-level: (i) differ; and (ii) depend on local collagen-apatite orientation and degree of calcification. Our findings confirm the strain concentration role of osteocyte lacunae, important for mechano-transduction. We hypothesize occurrence of micro-crack formation, leading either to remodeling or macroscopic fracture, when the computed strains exceed the elastic range observed in micro-structural testing.

  11. A reliable method for measuring proximal tibia and distal femur bone mineral density using dual-energy X-ray absorptiometry

    NARCIS (Netherlands)

    Bakkum, Arjan J. T.; Janssen, Thomas W. J.; Rolf, Marijn P.; Roos, Jan C.; Burcksen, Jos; Knol, Dirk L.; de Groot, Sonja

    Purpose: To assess the intra- and inter-rater reliability of a standardized protocol for measuring proximal tibia and distal femur bone mineral density (BMD) using dual-energy X-ray absorptiometry (DXA). Methods: Ten able-bodied individuals (7 males) participated in this study. During one

  12. Estimation of femoral bone density from trabecular direct wave and cortical guided wave ultrasound velocities measured at the proximal femur in vivo

    DEFF Research Database (Denmark)

    Barkmann, Reinhard; Dencks, Stefanie; Bremer, Alexander

    2008-01-01

    Bone mineral density (BMD) of the proximal femur is a predictor of hip fracture risk. We developed a Quantitative Ultrasound (QUS) scanner for measurements at this site with similar performance (FemUS). In this study we tested if ultrasound velocities of direct waves through trabecular bone and o...

  13. Coffee consumption and CYP1A2 genotype in relation to bone mineral density of the proximal femur in elderly men and women: a cohort study

    Directory of Open Access Journals (Sweden)

    Lind Lars

    2010-02-01

    Full Text Available Abstract Background Drinking coffee has been linked to reduced calcium conservation, but it is less clear whether it leads to sustained bone mineral loss and if individual predisposition for caffeine metabolism might be important in this context. Therefore, the relation between consumption of coffee and bone mineral density (BMD at the proximal femur in men and women was studied, taking into account, for the first time, genotypes for cytochrome P450 1A2 (CYP1A2 associated with metabolism of caffeine. Methods Dietary intakes of 359 men and 358 women (aged 72 years, participants of the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS, were assessed by a 7-day food diary. Two years later, BMD for total proximal femur, femoral neck and trochanteric regions of the proximal femur were measured by Dual-energy X-ray absorptiometry (DXA. Genotypes of CYP1A2 were determined. Adjusted means of BMD for each category of coffee consumption were calculated. Results Men consuming 4 cups of coffee or more per day had 4% lower BMD at the proximal femur (p = 0.04 compared with low or non-consumers of coffee. This difference was not observed in women. In high consumers of coffee, those with rapid metabolism of caffeine (C/C genotype had lower BMD at the femoral neck (p = 0.01 and at the trochanter (p = 0.03 than slow metabolizers (T/T and C/T genotypes. Calcium intake did not modify the relation between coffee and BMD. Conclusion High consumption of coffee seems to contribute to a reduction in BMD of the proximal femur in elderly men, but not in women. BMD was lower in high consumers of coffee with rapid metabolism of caffeine, suggesting that rapid metabolizers of caffeine may constitute a risk group for bone loss induced by coffee.

  14. Does lean tissue mass accrual during adolescence influence bone structural strength at the proximal femur in young adulthood?

    Science.gov (United States)

    Jackowski, S A; Lanovaz, J L; Van Oort, C; Baxter-Jones, A D G

    2014-04-01

    The purpose of this study was to identify whether young adult bone structural strength at the hip is associated with adolescent lean tissue mass (LTM) accrual. It was observed that those individuals who accrued more LTM from adolescence to adulthood had significantly greater adult bone structural strength at the hip. The purpose of this study was to identify whether young adult bone cross-sectional area (CSA), section modulus (Z), and outer diameter (OD) at the hip were associated with adolescent LTM accrual. One hundred three young adult participants (55 males, 48 females) were tertiled into adolescent LTM accrual groupings. LTM accrual was assessed by serial measures using dual energy X-ray absorptiometry (DXA) from adolescence to young adulthood (21.3 ± 1.3 years). CSA, Z, and OD at the narrow neck (NN) and femoral shaft (S) sites of the proximal femur were assessed in young adulthood (21.3 ± 4.5 years), using hip structural analysis. Group differences were assessed using an analysis of covariance, controlling for adult height, weight, sex, and physical activity levels. It was found that individuals with higher adjusted adolescent LTM accrual had significantly greater adult adjusted values of NNCSA (2.49 ± 0.06 vs 2.77 ± 0.07 cm(2)), NN Z (1.18 ± 0.04 vs 1.37 ± 0.04 cm(3)), NN OD (3.07 ± 0.04 vs 3.21 ± 0.04 cm), SCSA (3.45 ± 0.08 vs 3.88 ± 0.09 cm(3)), and SZ (1.77 ± 0.05 vs 2.00 ± 0.05 cm(3)) than individuals with lower LTM accrual (p femur.

  15. Anatomic study of the proximal third of the femur: femoroacetabular impact and the cam effect

    OpenAIRE

    Pedro José Labronici; Sergio Delmonte Alves; Anselmo Fernandes da Silva; Gilberto Ribeiro Giuberti; Rolix Hoffmann; Justino Nóbrega de Azevedo Neto; Jorge Luiz Mezzalira Penedo

    2009-01-01

    OBJETIVO: Analisar as varia��ões anatômicas da extremidade proximal do fêmur que pudessem desenvolver o impacto femoroacetabular. MÉTODOS: Foram utilizados 199 espécimes anatômicos de fêmures esqueleticamente maduros. Os fêmures foram medidos para determinar o ângulo da anteversão do colo femoral, ângulo cervicodiafisário, esfericidade da cabeça femoral em ântero-posterior e súpero-inferior, ângulo entre a epífise e o colo femoral anterior, ângulo entre a epífise e o colo em perfil, distância...

  16. A Study of Inflammatory/Necrosis Biomarkers in the Fracture of the Femur Treated with Proximal Femoral Nail Antirotation

    Directory of Open Access Journals (Sweden)

    Mariapaola Marino

    2015-01-01

    Full Text Available Pertrochanteric fractures are common injuries in adults and source of morbidity and mortality among the elderly. Different surgical techniques were recommended for their treatment but undoubtedly they add an additional inflammatory trauma along the fracture itself. Many attempts to quantify the degree of approach-related trauma are carried out through measurements of systemic inflammatory parameters. In this study we prospectively analyzed laboratory data of 20 patients over eighty with pertrochanteric fracture of the femur treated with proximal femoral nail antirotation (PFNA. This is an excellent device for osteosynthesis because it can be easily and quickly inserted by a mini-incision providing stable fixation and early full mobilization. Serum tumor necrosis factor-alpha (TNF-α, interleukin-6 (IL-6, C-reactive protein (CRP, and plasma creatin kinase (CK were evaluated 1 hour preoperatively and 24 hours postoperatively. Our results show that PFNA did not induce significant increments in serum levels of inflammatory cytokines TNF-α and IL-6; CRP was elevated preoperatively in correlation with waiting time for surgery; CRP and CK showed a significant increment in the first postoperatory day; CK increment was correlated with surgical time length. We conclude that, for the markers we analyzed, PFNA shows a low biomechanical-inflammatory profile that represents an advantage over other techniques.

  17. Using anisotropic 3D Minkowski functionals for trabecular bone characterization and biomechanical strength prediction in proximal femur specimens

    Science.gov (United States)

    Nagarajan, Mahesh B.; De, Titas; Lochmüller, Eva-Maria; Eckstein, Felix; Wismüller, Axel

    2014-04-01

    The ability of Anisotropic Minkowski Functionals (AMFs) to capture local anisotropy while evaluating topological properties of the underlying gray-level structures has been previously demonstrated. We evaluate the ability of this approach to characterize local structure properties of trabecular bone micro-architecture in ex vivo proximal femur specimens, as visualized on multi-detector CT, for purposes of biomechanical bone strength prediction. To this end, volumetric AMFs were computed locally for each voxel of volumes of interest (VOI) extracted from the femoral head of 146 specimens. The local anisotropy captured by such AMFs was quantified using a fractional anisotropy measure; the magnitude and direction of anisotropy at every pixel was stored in histograms that served as a feature vectors that characterized the VOIs. A linear multi-regression analysis algorithm was used to predict the failure load (FL) from the feature sets; the predicted FL was compared to the true FL determined through biomechanical testing. The prediction performance was measured by the root mean square error (RMSE) for each feature set. The best prediction performance was obtained from the fractional anisotropy histogram of AMF Euler Characteristic (RMSE = 1.01 ± 0.13), which was significantly better than MDCT-derived mean BMD (RMSE = 1.12 ± 0.16, p<0.05). We conclude that such anisotropic Minkowski Functionals can capture valuable information regarding regional trabecular bone quality and contribute to improved bone strength prediction, which is important for improving the clinical assessment of osteoporotic fracture risk.

  18. Estimation of Purkait's triangle method and alternative models for sex assessment from the proximal femur in the Spanish population.

    Science.gov (United States)

    Djorojevic, Mirjana; Roldán, Concepción; Botella, Miguel; Alemán, Inmaculada

    2016-01-01

    The current study was undertaken to test the validity and reproducibility of the Purkait triangle method and some alternative proposals for sex prediction from the proximal femur in the adult population of Spain. To that end, sexual dimorphism of the maximum femoral head diameter and the minimum femoral neck diameter were also evaluated. The study was conducted on 186 femora (109 males and 77 females) taken from the San José collection of identified individuals (Southern Spain). Discriminant function analyses (DFA) employing the jackknife procedure for cross-validations were considered. Overall, more than 94% of individuals of both sexes were correctly classified. The most dimorphic single variable from the triangle method was the intertrochanteric apex distance (BC) that reached 85.5% accuracy, falling below those obtained for the femoral head and femoral neck diameter, respectively, (89.8 and 91.9%). Combining BC with the neck diameter, the predictive ability increased to 92.5%; when femoral head diameter was added to the latter two, the classification success rate improved further up to 94.6% (94.1% after cross-validation). We conclude that the classification success rates of the Purkait's method remained considerably below any of those obtained with the models proposed in the present study which proved to be a much better and more reliable choice both as single predictors and in combination with other variables.

  19. The Relationship between Osteoarthritis of the Knee and Bone Mineral Density of Proximal Femur: A Cross-Sectional Study from a Korean Population in Women

    OpenAIRE

    Im, Gun-Il; Kwon, Oh-jin; Kim, Chang Hee

    2014-01-01

    Background The relationship between osteoarthritis (OA) and osteoporosis (OP) is complicated and it may differ according to the site or stage of disease. The purpose of this cross-sectional study is to examine the relationship between the severity of radiological knee OA and the degree of OP in the ipsilateral proximal femur as denoted by bone mineral density (BMD) in a Korean population, especially among women. Methods One hundred ninety-five female patients who had knee pain and radiologica...

  20. Bone loss at the distal femur and proximal tibia in persons with spinal cord injury: imaging approaches, risk of fracture, and potential treatment options.

    Science.gov (United States)

    Cirnigliaro, C M; Myslinski, M J; La Fountaine, M F; Kirshblum, S C; Forrest, G F; Bauman, W A

    2017-03-01

    Persons with spinal cord injury (SCI) undergo immediate unloading of the skeleton and, as a result, have severe bone loss below the level of lesion associated with increased risk of long-bone fractures. The pattern of bone loss in individuals with SCI differs from other forms of secondary osteoporosis because the skeleton above the level of lesion remains unaffected, while marked bone loss occurs in the regions of neurological impairment. Striking demineralization of the trabecular epiphyses of the distal femur (supracondylar) and proximal tibia occurs, with the knee region being highly vulnerable to fracture because many accidents occur while sitting in a wheelchair, making the knee region the first point of contact to any applied force. To quantify bone mineral density (BMD) at the knee, dual energy x-ray absorptiometry (DXA) and/or computed tomography (CT) bone densitometry are routinely employed in the clinical and research settings. A detailed review of imaging methods to acquire and quantify BMD at the distal femur and proximal tibia has not been performed to date but, if available, would serve as a reference for clinicians and researchers. This article will discuss the risk of fracture at the knee in persons with SCI, imaging methods to acquire and quantify BMD at the distal femur and proximal tibia, and treatment options available for prophylaxis against or reversal of osteoporosis in individuals with SCI.

  1. Forecasting Proximal Femur and Wrist Fracture Caused by a Fall to the Side during Space Exploration Missions to the Moon and Mars

    Science.gov (United States)

    Lewandowski, Beth E.; Myers, Jerry G.; Sulkowski, C.; Ruehl, K.; Licata, A.

    2008-01-01

    The possibility of bone fracture in space is a concern due to the negative impact it could have on a mission. The Bone Fracture Risk Module (BFxRM) developed at the NASA Glenn Research Center is a statistical simulation that quantifies the probability of bone fracture at specific skeletal locations for particular activities or events during space exploration missions. This paper reports fracture probability predictions for the proximal femur and wrist resulting from a fall to the side during an extravehicular activity (EVA) on specific days of lunar and Martian exploration missions. The risk of fracture at the proximal femur on any given day of the mission is small and fairly constant, although it is slightly greater towards the end of the mission, due to a reduction in proximal femur bone mineral density (BMD). The risk of wrist fracture is greater than the risk of hip fracture and there is an increased risk on Mars since it has a higher gravitational environment than the moon. The BFxRM can be used to help manage the risk of bone fracture in space as an engineering tool that is used during mission operation and resource planning.

  2. The incidence of fracture of the proximal femur in two million Canadians from 1972 to 1984. Projections for Canada in the year 2006.

    Science.gov (United States)

    Martin, A D; Silverthorn, K G; Houston, C S; Bernhardson, S; Wajda, A; Roos, L L

    1991-05-01

    Reported increases in the number of fractures of the proximal femur in Europe are greater than can be explained by demographic changes alone. This trend was assessed in Canada by examining hospital discharge records from the provinces of Saskatchewan and Manitoba from 1972 to 1984. The annual number of first fractures of the proximal femur in persons older than 50 years of age increased 59.7% in women and 42.2% in men during this time period. In most of the five-year age groups the percentage of increase in the number of fractures exceeded the percentage of increase in population of that age group. Annual age-specific incidences (by five-year age groups) increased exponentially with age, doubling every six years, and reached a maximum value of 4% in women older than 90 years of age. Annual age-adjusted incidences increased significantly over the study period in men and women. For the whole of Canada in 1987, it is estimated that there were 13,193 first fractures of the proximal femur in women and 4610 in men, and that in the year 2006 these will rise to 22,922 and 7846, respectively. The actual increase will be considerably greater if the age-specific incidences continue to increase as they have from 1972 to 1984. The gradual decline in physical activity, which contributes to bone loss, may be one etiological factor of this trend during the last half century.

  3. Coronal subluxation of the proximal tibia relative to the distal femur after opening wedge high tibial osteotomy.

    Science.gov (United States)

    Akamatsu, Yasushi; Ohno, Satoshi; Kobayashi, Hideo; Kusayama, Yoshihiro; Kumagai, Ken; Saito, Tomoyuki

    2017-01-01

    The coronal subluxation of the proximal tibia relative to the distal femur is a common radiological finding in patients with knee osteoarthritis. The purpose was to evaluate whether the coronal subluxation was corrected after opening wedge high tibial osteotomy (OWHTO), and whether this subluxation was one cause of inconsistency between the actual and predicted alignments (correction loss). Fifty-one patients (55 knees) were treated with OWHTO. The change of location between the intersection points of the femoral and tibial axes on the tibial plateau (subluxation-C), the change of location between the lines through the most lateral points of the lateral femoral and tibial condyles (subluxation-L), and joint space angle (JSA) were compared in standing knee radiographs before and one year after OWHTO. The subluxation-C and subluxation-L were converted to a percentage of the tibial plateau width. The mean subluxation-C of 6.5% before OWHTO significantly increased to a mean subluxation-C of 7.3% one year after OWHTO. The mean subluxation-L of 6.3% and JSA of 4.5° before OWHTO significantly decreased to a subluxation-L of 1.8% and JSA of 3.3° one year after OWHTO. The change in subluxation-L correlated with the change in femorotibial angle and correction loss (r=0.634, Pfemur after OWHTO. This medial shift correlated with the correction loss. The coronal subluxation might be one cause of correction loss. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Variable Flip Angle 3D Fast Spin-Echo Sequence Combined with Outer Volume Suppression for Imaging Trabecular Bone Structure of the Proximal Femur

    Science.gov (United States)

    Han, Misung; Chiba, Ko; Banerjee, Suchandrima; Carballido-Gamio, Julio; Krug, Roland

    2014-01-01

    Purpose To demonstrate the feasibility of using a variable flip angle 3D fast spin-echo (3D VFA-FSE) sequence combined with outer volume suppression for imaging of trabecular bone structure at the proximal femur in vivo at 3T. Materials and Methods The 3D VFA-FSE acquisition was optimized to minimize blurring and to provide high signal-to-noise ratio (SNR) from bone marrow. Outer volume suppression was achieved by applying three quadratic-phase radio-frequency pulses. The SNR and trabecular bone structures from 3D VFA-FSE was compared with those from previously demonstrated multiple-acquisition 3D balanced steady-state free precision (bSSFP) using theoretical simulations, ex vivo experiments, and in vivo experiments. Results Our simulation demonstrated that 3D VFA-FSE can provide at least 35% higher SNR than 3D bSSFP, which was confirmed by the ex vivo and in vivo experiments. The ex vivo experiments demonstrated a good correlation and agreement between bone structural paramters obtained with the two sequences. The proposed sequence depicted trabecular bone structure at the proxiaml femur in vivo well without visible suppression artifacts and provided a mean SNR of 11.0. Conclusion The reduced-FOV 3D VFA-FSE sequence can depict the trabecular bone structure of the proximal femur in vivo with minimal blurring and high SNR efficiency. PMID:24956149

  5. What Sport Activity Levels Are Achieved in Patients After Resection and Endoprosthetic Reconstruction for a Proximal Femur Bone Sarcoma?

    Science.gov (United States)

    Hobusch, Gerhard M; Bollmann, Jakob; Puchner, Stephan E; Lang, Nikolaus W; Hofstaetter, Jochen G; Funovics, Philipp T; Windhager, Reinhard

    2017-03-01

    patients available for study, we could not determine that prosthetic failures were associated with sport activity levels. Patients who survive primary malignant bone tumors in the proximal femur reconstructed by megaprostheses are able to perform some sports activities. The estimates of activity levels made in this study probably are best-case estimates, given that some patients were lost to followup; patients unaccounted for might not be doing as well as those represented here. Also, the degree to which sports participation influences implant durability remains, for the most part, unanswered; studies with more patients and longer followup will be needed to determine to what degree prosthesis survivorship relates to sporting activity levels. Most patients perform low-impact sports and at a lower level than they had preoperatively. Because this is a preliminary study of a select group of patients, further information is necessary to weight the benefits of higher sports activity levels against potential risks. If this can be confirmed in a larger number of patients, the information may guide surgeons in their discussion with patients preoperatively and give them some objective assessment of what to expect regarding sports activities. Level IV, therapeutic study.

  6. Quantitative local topological texture properties obtained from radiographs of the proximal femur in patients with pertrochanteric and transcervical hip fractures

    Science.gov (United States)

    Boehm, H. F.; Lutz, J.; Koerner, M.; Notohamiprodjo, M.; Reiser, M.

    2009-02-01

    The incidence of osteoporosis and associated fractures becomes an increasingly relevant issue for the public health institutions of industrialized nations. Fractures of the hip represent the worst complication of osteoporosis with a significantly elevated rate of mortality. Prediction of fracture risk is a major focus of osteoporosis research and, over the years, has been approched from different angles. There exist two distinct subtypes of transcervical and pertrochanteric hip fracture that can be distinguished on the basis of the anatomical location of the injury. While the epidemiology of hip fractures has been well described, typically, little or no distinction is made between the subtypes. The object of this study was to determine whether local topological texture properties based on the Minkowski Functionals (MF) obtained from standard radiographs of the proximal femur in patients with hip fracture can be used to differentiate between the two types of fracture pattern. The texture features were extracted from standardized regions of interest (femoral head, neck, and pertrochanteric region) in clinical radiographs of the hip obtained from 90 post-menopausal women (69.8 +/- 7.9 yrs). 30 of the women had sustained pertrochanteric fractures, 30 had transcervical hip fractures and 30 were age-matched controls. We determined an optimized topological parameter MF2Dloc using an integrative filtering procedure based on a sliding-windows algorithm. Statistical relationship between the fracture type (pertrochanteric/transcervical) and the value of MF2Dloc was assessed by receiver-operator characteristic (ROC) analysis. Depending on the anatomical location of the region of interest for texture analysis correct classification of tanscervial and pertrochanteric fractures ranged from AUC = 0.79 to 0.98. In conclusion, quantitative texture properties of trabecular bone extracted from radiographs of the hip can be used to identify patients with hip fracture and to distinguish

  7. Three-dimensional micro-level computational study of Wolff's law via trabecular bone remodeling in the human proximal femur using design space topology optimization.

    Science.gov (United States)

    Boyle, Christopher; Kim, Il Yong

    2011-03-15

    The law of bone remodeling, commonly referred to as Wolff's Law, asserts that the internal trabecular bone adapts to external loadings, reorienting with the principal stress trajectories to maximize mechanical efficiency creating a naturally optimum structure. The goal of the current study was to utilize an advanced structural optimization algorithm, called design space optimization (DSO), to perform a micro-level three-dimensional finite element bone remodeling simulation on the human proximal femur and analyse the results to determine the validity of Wolff's hypothesis. DSO optimizes the layout of material by iteratively distributing it into the areas of highest loading, while simultaneously changing the design domain to increase computational efficiency. The result is a "fully stressed" structure with minimized compliance and increased stiffness. The large-scale computational simulation utilized a 175 μm mesh resolution and the routine daily loading activities of walking and stair climbing. The resulting anisotropic trabecular architecture was compared to both Wolff's trajectory hypothesis and natural femur samples from literature using a variety of visualization techniques, including radiography and computed tomography (CT). The results qualitatively revealed several anisotropic trabecular regions, that were comparable to the natural human femurs. Quantitatively, the various regional bone volume fractions from the computational results were consistent with quantitative CT analyses. The global strain energy proceeded to become more uniform during optimization; implying increased mechanical efficiency was achieved. The realistic simulated trabecular geometry suggests that the DSO method can accurately predict bone adaptation due to mechanical loading and that the proximal femur is an optimum structure as the Wolff hypothesized. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  8. Bone mineral density measurements of the proximal femur from routine contrast-enhanced MDCT data sets correlate with dual-energy X-ray absorptiometry.

    Science.gov (United States)

    Gruber, M; Bauer, J S; Dobritz, M; Beer, A J; Wolf, P; Woertler, K; Rummeny, E J; Baum, T

    2013-02-01

    To evaluate the utility of femoral bone mineral density (BMD) measurements in routine contrast-enhanced multi-detector computed tomography (ceMDCT) using dual-energy X-ray absorptiometry (DXA) as the reference standard. Forty-one patients (33 women, 8 men) underwent DXA measurement of the proximal femur. Subsequently, transverse sections of routine ceMDCT of these patients were used to measure BMD of the femoral head and femoral neck. The MDCT-to-DXA conversion equations for BMD and T-score were calculated using linear regression analysis. The conversion equations were applied to the MDCT data sets of 382 patients (120 women, 262 men) of whom 74 had osteoporotic fractures. A correlation coefficient of r = 0.84 (P < 0.05) was calculated for BMD(MDCT) values of the femoral head and DXA T-scores of the total proximal femur using the conversion equation T-score = 0.021 × BMD(MDCT) - 5.90. The correlation coefficient for the femoral neck was r = 0.79 (P < 0.05) with the conversion equation T-score = 0.016 × BMD(MDCT) - 4.28. Accordingly, converted T-scores for the femoral neck in patients with versus those without osteoporotic fractures were significantly different (female, -1.83 versus -1.47; male, -1.86 versus -1.47; P < 0.05). BMD measurements of the proximal femur were computed in routine contrast-enhanced MDCT and converted to DXA T-scores, which adequately differentiated patients with and without osteoporotic fractures.

  9. Bone mineral density measurements of the proximal femur from routine contrast-enhanced MDCT data sets correlate with dual-energy X-ray absorptiometry

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, M. [Medical University of Vienna, Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Vienna (Austria); Bauer, J.S.; Dobritz, M.; Woertler, K.; Rummeny, E.J.; Baum, T. [Technische Universitaet Muenchen, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Beer, A.J. [Technische Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Wolf, P. [Technische Universitaet Muenchen, Institute for Medical Statistics and Epidemiology, Munich (Germany)

    2013-02-15

    To evaluate the utility of femoral bone mineral density (BMD) measurements in routine contrast-enhanced multi-detector computed tomography (ceMDCT) using dual-energy X-ray absorptiometry (DXA) as the reference standard. Forty-one patients (33 women, 8 men) underwent DXA measurement of the proximal femur. Subsequently, transverse sections of routine ceMDCT of these patients were used to measure BMD of the femoral head and femoral neck. The MDCT-to-DXA conversion equations for BMD and T-score were calculated using linear regression analysis. The conversion equations were applied to the MDCT data sets of 382 patients (120 women, 262 men) of whom 74 had osteoporotic fractures. A correlation coefficient of r = 0.84 (P < 0.05) was calculated for BMD{sub MDCT} values of the femoral head and DXA T-scores of the total proximal femur using the conversion equation T-score = 0.021 x BMD{sub MDCT} - 5.90. The correlation coefficient for the femoral neck was r = 0.79 (P < 0.05) with the conversion equation T-score = 0.016 x BMD{sub MDCT} - 4.28. Accordingly, converted T-scores for the femoral neck in patients with versus those without osteoporotic fractures were significantly different (female, -1.83 versus -1.47; male, -1.86 versus -1.47; P < 0.05). BMD measurements of the proximal femur were computed in routine contrast-enhanced MDCT and converted to DXA T-scores, which adequately differentiated patients with and without osteoporotic fractures. (orig.)

  10. Age estimation in a sub-adult Western Australian population based on the analysis of the pelvic girdle and proximal femur.

    Science.gov (United States)

    Sullivan, Siobhan; Flavel, Ambika; Franklin, Daniel

    2017-10-16

    The accurate and precise estimation of skeletal age by a forensic anthropologist is both a professional and judicial requirement. When unknown skeletal remains are referred to the anthropologist, the estimation of the requisite biological attributes (e.g., age and sex) should accordingly be based on the application of population-specific standards (statistical data). Deviations from the latter practice may result in reduced accuracy and compromised identification. Towards informing appropriate forensic practice, the aim of the present study is to develop statistically quantified age estimation models for a contemporary sub-adult Western Australian population based on the timing of fusion in the os coxa and proximal femur. The study sample comprises 562 known age and sex MDCT scans (292 male, 270 female) representing contemporary Western Australian individuals birth through 30 years of age. Scans are viewed in multi-planar reconstructed (MPR) and/or three-dimensionally reconstructed images using OsiriX(®). Fusion status is scored according to a three-stage system across a total of nine sites in the proximal femur and os coxae. Observer accordance, bilateral asymmetry and sex-specific variation in fusion timing are statistically quantified. Polynomial regression is used to formulate age prediction models; transition analysis is used to calculate age ranges and determine the mean age for transition between an unfused, fusing and fused status. Observer accordance in stage assignation is acceptable (ϰ=0.79) and there is no significant bilateral variation in fusion timing. It was found that the mean age of commencement of fusion is significantly earlier (∼2 years) in females. The accuracy (SEE) of the polynomial models ranges from ±3.29 to ±3.80 years and the transition analysis shows that fusion of the iliac crest is delayed in comparison to other attributes of os coxa and proximal femur. Results of the present study confirm that the pelvic girdle and proximal

  11. Measurements of bone mineral density in the lumbar spine and proximal femur using lunar prodigy and the new pencil-beam dual-energy X-ray absorptiometry

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Dongil [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Department of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Deog-Yoon [Kyung Hee University, Department of Nuclear Medicine, College of Medicine, Seoul (Korea, Republic of); Han, Chung Soo [Kyung Hee University, Department of Orthopedic Surgery, College of Medicine, Seoul (Korea, Republic of); Kim, Seonwoo [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Samsung Medical Center, Biostatistics Unit, Samsung Biomedical Research Institute, Seoul (Korea, Republic of); Bok, Hae Sook [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Huh, Wooseong [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Division of Nephrology, Samsung Medical Center, Seoul (Korea, Republic of); Ko, Jae-Wook [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Division of Clinical Pharmacology, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Hong, Sung Hwa [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical Center, Seoul (Korea, Republic of)

    2010-11-15

    We evaluated the correlation of the absolute bone mineral density (BMD) values of the lumbar spine and standard sites of the proximal femur obtained from a Lunar Prodigy and the newly developed pencil-beam dual-energy X-ray absorptiometry (Dexxum). Between June 2008 and December 2008, 79 Korean volunteers were enrolled. Measurements were obtained on the same day using both densitometers. The absolute BMD values (g/cm{sup 2}) from the two densitometers were evaluated using Pearson's correlation analysis with Bonferroni's correction for the three clinically important sites. In order to evaluate precision, we performed duplicate Dexxum measurements, and calculated the within-subject coefficient of variation (WSCV). The Pearson's correlation coefficient (r) of BMD values for the total proximal femur, femoral neck, and lumbar spine by the two densitometers were 0.926, 0.948, and 0.955 respectively, and the null hypotheses of r = 0.8 were all rejected (p < 0.001 by one-sided Z-test with Fisher's z-transformation for each site). The T-scores (r {>=} 0.842) and Z-scores (r {>=} 0.709) also showed strong positive correlations. The duplicate BMD values of Dexxum showed a high level of precision (WSCV {<=} 4.27%). Dexxum measurements of BMD, T-scores, and Z-scores showed a strong linear correlation with those measured on Lunar Prodigy. (orig.)

  12. Anatomia radiográfica da região proximal do fêmur: correlação com a ocorrência de fraturas Radiographic anatomy of the proximal femur: correlation with the occurrence of fractures

    Directory of Open Access Journals (Sweden)

    Robinson Esteves Santos Pires

    2012-01-01

    Full Text Available OBJETIVO: Avaliar se existe correlação entre parâmetros radiográficos da anatomia da região proximal do fêmur e a ocorrência de fraturas. MÉTODOS: Trezentas e cinco radiografias digitais da bacia foram analisadas na incidência ântero-posterior. Destas radiografias, vinte e sete apresentavam fratura do colo femoral ou transtrocantérica. Os parâmetros anatômicos analisados foram: Largura do colo femoral (LCF, comprimento do colo femoral (CCF, comprimento do eixo femoral (CEF, ângulo cérvico-diafisário (ACD, distância entre as lágrimas acetabulares (DLA e a distância grande trocânter- sínfise púbica (DGTSP.Foram analisadas, comparativamente, as radiografias com e sem fratura da região proximal do fêmur, para verificar se existem parâmetros radiográficos que estão associados com maior probabilidade de ocorrência de fratura do colo femoral ou transtrocantérica. RESULTADOS: Não foi encontrada diferença entre os parâmetros anatômicos dos grupos com e sem fratura na região proximal do fêmur. CONCLUSÃO: Não foi encontrada nenhuma associação entre alterações anatômicas na região proximal do fêmur e maior susceptibilidade à ocorrência de fraturas. Nível de evidência IV, Estudo Transversal.OBJECTIVE: To evaluate the correlation between radiographic parameters of the proximal femur anatomy and fractures. METHODS: Three hundred and five digital x-rays of the pelvis were analyzed in the anteroposterior view. Of these x-rays, twenty-seven showed femoral neck or transtrochanteric fractures. The anatomical parameters analyzed were: femoral neck width (FNW, femoral neck length (FNL, femoral axis length (FAL, cervicodiaphyseal angle (CDA, acetabular tear-drop distance (ATD and great trochanter-pubic symphysis distance (GTPSD. The analysis was performed by comparing the results of the x-rays with and without proximal femoral fracture, to establish a correlation between them. RESULTS: No differences were found between

  13. A retrospective analysis of the InterTan nail and proximal femoral nail anti-rotation-Asia in the treatment of unstable intertrochanteric femur fractures in the elderly.

    Science.gov (United States)

    Yu, Weiguang; Zhang, Xinchao; Zhu, Xingfei; Hu, Jun; Liu, Yunjiang

    2016-01-15

    The purpose of this study was to compare the clinical outcomes of elderly patients undergoing surgery for treatment of unstable trochanteric fractures receiving either proximal femoral nails anti-rotation-Asia (PFNA-IIs) or InterTan nails (ITs). Between January 1, 2012, and June 31, 2015, 168 elderly patients with unstable intertrochanteric femur fractures enrolled in this study. The only intervention was ITs or PFNA-IIs of the unstable trochanteric femur fractures. Follow-up was at 1, 3, 6, and 12 months postoperatively and yearly thereafter. Intraoperative variables and postoperative complications were compared between the two groups. Eight patients died, six were too infirmed for follow-up, and seven were lost during follow-up, leaving 147 patients meeting the criteria were evaluated at a mean follow-up of 20 months (range 16-26 months). Significant differences were observed between the two groups regarding local complications (IT, n = 10 vs. PFNA-II, n = 20), varus collapse of the head/neck or femoral shaft fractures at the tip of the nail (IT, n = 1 vs. PFNA-II, n = 8), femoral neck shortening (IT, 4.4 ± 1.1 mm vs. PFNA-II, 7.4 ± 2.4 mm), fracture healing time (IT, 14.7 ± 2.1 weeks vs. PFNA-II, 15.7 ± 2.4 weeks), femoral shaft fractures (IT, n = 0 vs. PFNA-II, n = 4), rotational loss of reduction (IT, n = 0 vs. PFNA-II, n = 9), lateral cortex fractures of the proximal femur or lateral greater trochanter fractures (IT, n = 8 vs. PFNA-II, n = 1), operative time (IT, 71.9 ± 6.8 min vs. PFNA-II, 52.3 ± 4.0 min), intraoperative blood loss (IT, 190.6 ± 6.0 mL vs. PFNA-II, 180.9 ± 10.8 mL), fluoroscopy time (IT, 5.0 ± 0.48 min vs. PFNA-II, 2.8 ± 0.33 min), hospital stay (IT, 9.65 ± 0.95 days vs. PFNA-II, 8.58 ± 0.93 days), cut-out (IT, n = 0 vs. PFNA-II, n = 6), and tip-apex distance (IT, 26.7 ± 0.91 mm vs. PFNA-II, 23.2 ± 1.22 mm). No significant differences existed for the other observation indexes (p > 0.05). The IT nail may have more advantage for

  14. Vascularised and modified lower-leg rotationplasty for the treatment of severe infection and bone loss of the proximal femur: a case report.

    Science.gov (United States)

    Fischer, Sebastian; Hirche, Christoph; Heppert, Volkmar G; Grützner, Paul A; Kneser, Ulrich; Kremer, Thomas

    2017-09-19

    We report a reconstructive case in a paraplegic patient, who suffers from a severe proximal femur infection. Aiming at the preservation of the capacity to remain in a seated position to operate a wheelchair, lower leg rotationplasty was considered suitable for reconstruction. Due to severe infection and subclinical femoral artery stenosis, rotationplasty was supercharged by the inferior epigastric artery. Furthermore, extensor tendons of the foot were attached to the acetabulum to facilitate stability of the neo-hip joint. Follow-up examination 1 year after surgery revealed no complications and a satisfied patient. Especially in paraplegic patients, lower leg rotationplasty is a possible treatment option for severe femoral infection. Supercharging provides well-vascularised tissue to the former infection site and improves wound healing.

  15. 3D bone mineral density distribution and shape reconstruction of the proximal femur from a single simulated DXA image: an in vitro study

    Science.gov (United States)

    Whitmarsh, Tristan; Humbert, Ludovic; De Craene, Mathieu; del Río Barquero, Luis M.; Fritscher, Karl; Schubert, Rainer; Eckstein, Felix; Link, Thomas; Frangi, Alejandro F.

    2010-03-01

    Area Bone Mineral Density (aBMD) measured by Dual-energy X-ray Absorptiometry (DXA) is an established criterion in the evaluation of hip fracture risk. The evaluation from these planar images, however, is limited to 2D while it has been shown that proper 3D assessment of both the shape and the Bone Mineral Density (BMD) distribution improves the fracture risk estimation. In this work we present a method to reconstruct both the 3D bone shape and 3D BMD distribution of the proximal femur from a single DXA image. A statistical model of shape and a separate statistical model of the BMD distribution were automatically constructed from a set of Quantitative Computed Tomography (QCT) scans. The reconstruction method incorporates a fully automatic intensity based 3D-2D registration process, maximizing the similarity between the DXA and a digitally reconstructed radiograph of the combined model. For the construction of the models, an in vitro dataset of QCT scans of 60 anatomical specimens was used. To evaluate the reconstruction accuracy, experiments were performed on simulated DXA images from the QCT scans of 30 anatomical specimens. Comparisons between the reconstructions and the same subject QCT scans showed a mean shape accuracy of 1.2mm, and a mean density error of 81mg/cm3. The results show that this method is capable of accurately reconstructing both the 3D shape and 3D BMD distribution of the proximal femur from DXA images used in clinical routine, potentially improving the diagnosis of osteoporosis and fracture risk assessments at a low radiation dose and low cost.

  16. Tibia-hindfoot osteomusculocutaneous rotationplasty with calcaneopelvic arthrodesis for extensive loss of bone from the proximal part of the femur. A report of two cases.

    Science.gov (United States)

    Peterson, C A; Koch, L D; Wood, M B

    1997-10-01

    We report a new technique to create an effective lower extremity weight-bearing stump for two patients who had extensive segmental loss of femoral bone proximal to the distal femoral condyles. One patient had previously had complete resection of the proximal part of the femur because of an infection following the insertion of a custom femoral replacement and hip arthroplasty prosthesis. The other patient had had débridement of the femur from the subcapital line to the femoral condyles because of post-traumatic osteomyelitis after failure of a reconstruction with a massive allograft. Both patients were managed with a tibia-hindfoot osteomusculocutaneous rotationplasty after transtarsal (Chopart) amputation, with calcaneopelvic arthrodesis to create stable fixation of the extremity to the pelvis; this fixation allowed flexion, extension, abduction, and adduction of the hip by means of the retained tibiotalar and subtalar joints. At the time of the latest follow-up (at thirty-three and forty-four months), both patients were bearing full weight, without pain, with the use of a standard above-the-knee-amputation prosthesis. We report this procedure as a useful alternative to disarticulation at the level of the hip in patients who have massive loss of femoral bone and destruction of the hip joint in association with scarred and previously infected soft tissues and are not considered to be candidates for other forms of limb-preservation reconstruction. The patient must be willing to accept the equivalent of a low above-the-knee amputation and recognize the potential value of a weight-bearing stump.

  17. Estudo anatômico do terço proximal do fêmur: impacto femoroacetabular e o efeito cam Anatomic study of the proximal third of the femur: femoroacetabular impact and the cam effect

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    Pedro José Labronici

    2009-04-01

    Full Text Available OBJETIVO: Analisar as varia��ões anatômicas da extremidade proximal do fêmur que pudessem desenvolver o impacto femoroacetabular. MÉTODOS: Foram utilizados 199 espécimes anatômicos de fêmures esqueleticamente maduros. Os fêmures foram medidos para determinar o ângulo da anteversão do colo femoral, ângulo cervicodiafisário, esfericidade da cabeça femoral em ântero-posterior e súpero-inferior, ângulo entre a epífise e o colo femoral anterior, ângulo entre a epífise e o colo em perfil, distância em ântero-posterior a 5mm da junção cabeça e colo e distância em ântero-posterior da base do colo. RESULTADOS: Observou-se que o subgrupo com impacto apresentou diâmetro da junção a 5mm (p = 0,0001 e cam-cabeça (% (p = 0,0001 significativamente maiores e base-cam (% (p = 0,0001 significativamente menor que o subgrupo sem impacto. Identificou-se que cam-cabeça (% > 80 e base-cam (% OBJECTIVE: to analyze anatomical variations of the proximal end of femur that could cause a femoroacetabular impact. METHODS: 199 skeletically mature anatomical specimens of femurs were used. The femurs were measured in order to determine the anteversion angle of the femoral neck, neckshaft angle, sphericity of the femoral head at anteroposterior and superoinferior, angle between epiphysis and the anterior femoral neck, angle between epiphysis and the neck at lateral plane, anteroposterior distance at 5mm of the head and neck junction and anteroposterior distance of the neck base. RESULTS: we found that the impact subgroup presented a significantly larger junction diameter of 5mm (p = 0.0001 and cam-head (% (p= 0.0001, while base-cam (% (p = 0.0001 showed a significantly smaller diameter than the subgroup without impact. It was identified that cam-head (% > 80 e base-cam (% < 73 were identified as the optimal impact points. CONCLUSION: our study showed that the effect cam, caused by anatomical variations of the proximal femoral end focused the

  18. The Influence of High-Impact Exercise on Cortical and Trabecular Bone Mineral Content and 3D Distribution Across the Proximal Femur in Older Men: A Randomized Controlled Unilateral Intervention.

    Science.gov (United States)

    Allison, Sarah J; Poole, Kenneth E S; Treece, Graham M; Gee, Andrew H; Tonkin, Carol; Rennie, Winston J; Folland, Jonathan P; Summers, Gregory D; Brooke-Wavell, Katherine

    2015-09-01

    Regular exercisers have lower fracture risk, despite modest effects of exercise on bone mineral content (BMC). Exercise may produce localized cortical and trabecular bone changes that affect bone strength independently of BMC. We previously demonstrated that brief, daily unilateral hopping exercises increased femoral neck BMC in the exercise leg versus the control leg of older men. This study evaluated the effects of these exercises on cortical and trabecular bone and its 3D distribution across the proximal femur, using clinical CT. Fifty healthy men had pelvic CT scans before and after the exercise intervention. We used hip QCT analysis to quantify BMC in traditional regions of interest and estimate biomechanical variables. Cortical bone mapping localized cortical mass surface density and endocortical trabecular density changes across each proximal femur, which involved registration to a canonical proximal femur model. Following statistical parametric mapping, we visualized and quantified statistically significant changes of variables over time in both legs, and significant differences between legs. Thirty-four men aged mean (SD) 70 (4) years exercised for 12-months, attending 92% of prescribed sessions. In traditional regions of interest, cortical and trabecular BMC increased over time in both legs. Cortical BMC at the trochanter increased more in the exercise than control leg, whereas femoral neck buckling ratio declined more in the exercise than control leg. Across the entire proximal femur, cortical mass surface density increased significantly with exercise (2.7%; p 6%) at anterior and posterior aspects of the femoral neck and anterior shaft. Endocortical trabecular density also increased (6.4%; p 12% at the anterior femoral neck, trochanter, and inferior femoral head. Odd impact exercise increased cortical mass surface density and endocortical trabecular density, at regions that may be important to structural integrity. These exercise-induced changes were

  19. Proximal Femur Bone Density Decreases up to 5 Years After Total Hip Arthroplasty in Young, Active Patients.

    Science.gov (United States)

    Nam, Denis; Barrack, Robert L; Clohisy, John C; Nunley, Ryan M

    2016-12-01

    The number of young, active patients undergoing hip arthroplasty continues to increase. The purpose of this study was to evaluate femoral bone density over a 5-year period after hip arthroplasty in young, active patients. A total of 96 patients (103 hips) with a presymptomatic University of California at Los Angeles (UCLA) score ≥6 who had a total hip arthroplasty (THA; 45 hips) or surface replacement arthroplasty (SRA; 58 hips) were prospectively enrolled. UCLA and Harris Hip Scores were collected preoperatively and postoperatively, and dual energy X-ray absorptiometry scans were performed at 6 weeks, 6 months, 1 year, 2 years, and 5 years postoperatively. Bone density was analyzed for 7 traditional Gruen zones in both groups and 6 femoral neck zones in the SRA group. Bone density ratios were calculated for change in bone density compared with baseline. No differences were present in the preoperative or postoperative UCLA or Harris Hip Scores between the SRA and THA cohorts (P = .07-.7). In the THA group, bone density never returned to baseline during the 5-year period in Gruen zones 1 (91.2% of baseline), 2 (94.8%), 6 (97.3%), and 7 (89.2%). There were no decreases in bone mineral density ratio for the femoral Gruen zones in the SRA group at any interval. Femoral neck bone density after SRA increased on the lateral, tension side up to 5 years postoperatively (P femur in Gruen zones 1, 2, and 7 over time. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Finite element model of the proximal femur under consideration of the hip centralizing forces of the iliotibial tract.

    Science.gov (United States)

    Birnbaum, K; Pandorf, T

    2011-01-01

    the aim of our investigations was the development of a finite element model of the hip joint under consideration of the hip centralizing forces of the iliotibial tract within different femoral neck angles and its influence to the centralizing of the femoral head to the acetabulum. for the development of the finite element model of the femur and the iliotibial tract we utilized the program IDEAS 3D as well as the material/lengthening characteristics of the iliotibial tract. In the following step we developed a hip joint model with different centrum-collum-diaphysis-angles of 115°, 128° and 155° for determination of the IT force and the consequential force on the femoral head. with a coxa vara the force on the femoral head in relation to the physiological centrum-collum-diaphysis-angle and the coxa valga decreased (115°=1601N, 128°=2360N, and 155°=2422N). On the other side the hip centralizing forces of the iliotibial tract within a coxa vara increased in comparison to 128° (physiological) and 155° (valga) (115°=997N, 128°=655,5N, and 155°=438N). Within a coxa valga a higher compressive force on the femoral head and with a coxa vara a decreasing compressive force on the femoral head occurred. the clinical relevance consists in the predictability of an increasing or decreasing band wiring effect of the iliotibial tract in reliance to the centrum-collum-diaphysis-angle of the femoral neck and its importance for the displacement osteotomy of the growing hip. 2010 Elsevier Ltd. All rights reserved.

  1. INTERTAN nail versus proximal femoral nail antirotation-Asia for intertrochanteric femur fractures in elderly patients with primary osteoporosis

    OpenAIRE

    Zhang, Hui; Zeng, Xianshang; Zhang, Nan; Zeng, Dan; Xu, Ping; Zhang, Lili; Chen, Deng; Yu, Weiguang; Zhang, Xinchao

    2017-01-01

    Objectives To compare the long-term functional and radiographic outcomes of the proximal femoral nail antirotation-Asia (PFNA-II) and INTERTAN nail (IT) in the management of intertrochanteric femoral fractures (IFFs) (AO/OTA Type 31A1.1-A2.3) in elderly patients with primary osteoporosis. Methods A retrospective comparative study was performed in our institution. From January 2009 to March 2012, 243 patients with osteoporosis (243 hips) with IFFs (AO/OTA Type 3.1A1.1-A2.3) underwent repair wi...

  2. Fraturas proximais do fêmur em idosos: qual o melhor tratamento? Proximal fracture of the femur on the elderly: what's the best treatment?

    Directory of Open Access Journals (Sweden)

    Lygia Paccini Lustosa

    2009-01-01

    Full Text Available As fraturas proximais do fêmur em idosos representam um sério problema dentro do contexto da saúde pública, devido aos elevados custos econômicos para o tratamento e as suas consequências, assim como pela alta taxa de morbidade e mortalidade. O objetivo desse estudo foi discutir quais os tratamentos mais indicados para esse tipo de fratura, em idosos, por meio de uma revisão da literatura. As bases de dados pesquisadas foram MEDLINE, COCHRANE e PEDro. Os critérios de inclusão foram estudos publicados nos últimos sete anos; nos idiomas português, inglês e espanhol; realizados em seres humanos, sem distinção de gênero e com idade maior que 60 anos; estudos com desenho metodológico de ensaios clínicos, ensaios clínicos aleatorizados e revisões sistemáticas com e sem meta-análise. Foram encontrados sete artigos e após a análise pode se afirmar que não existe um tratamento específico para as fraturas proximais do fêmur em idosos. O tratamento normalmente indicado na maioria dessas fraturas é cirúrgico e requer envolvimento fisioterápico para uma reabilitação adequada. Apesar da dificuldade de comparação entre os estudos, foi observado que uma equipe de profissionais da saúde parece promover uma reabilitação mais efetiva, além de prevenir complicações.The proximal fractures of the femur on the elderly represent a serious problem inside the public health context, because of the high economic costs needed for the treatment and it's consequence, as the high taxes of morbidity and mortality. The goal of this study was to discuss, through a literature revision, which is the most indicated treatment for the proximal fractures of the femur, on the elderly. The researched data bases were MEDLINE, COCHRANE and PEDro. The inclusion criterions were published studies on the last seven years, only on the Portuguese, English and Spanish languages, accomplished on human beings, with no genre distinction and with ages above 60

  3. Malignant tumor of the distal part of the femur or the proximal part of the tibia: endoprosthetic replacement or rotationplasty. Functional outcome and quality-of-life measurements.

    Science.gov (United States)

    Hillmann, A; Hoffmann, C; Gosheger, G; Krakau, H; Winkelmann, W

    1999-04-01

    The present study was performed to determine whether there is a difference, with regard to functional outcome and quality of life, between endoprosthetic replacement and rotationplasty for the treatment of malignant tumors of the distal part of the femur or the proximal part of the tibia. Sixty-seven patients, between the ages of eleven and twenty-four years at the time of the diagnosis, had a malignant tumor of the distal part of the femur or the proximal part of the tibia. A rotationplasty was performed in thirty-three patients, and an endoprosthetic replacement was done in thirty-four patients. The median duration of follow-up was six years and one month (range, two years to sixteen years and two months). The scale developed by the Musculoskeletal Tumor Society was used to evaluate the functional results. Quality-of-life issues were assessed with the questionnaire developed by the European Organization for Research and Treatment of Cancer. The patients who had had a rotationplasty had a mean functional score, according to the system of the Musculoskeletal Tumor Society, of 24 points, and the patients who had had an endoprosthetic replacement had a mean score of 25 points. This difference was not found to be significant, with the numbers available (p = 0.47). Only one patient who had had a rotationplasty used an assistive device when walking long distances, whereas six patients who had had an endoprosthetic replacement used an assistive device. This difference was significant (protationplasty could participate in hobbies such as carpentry and sports as well as in other daily activities to a significantly greater degree than those who had had an endoprosthetic replacement (p = 0.001). Restriction in daily activities due to pain was significantly less common in the group that had had a rotationplasty than it was in the group that had had an endoprosthetic replacement (p = 0.047). Rotationplasty was not associated with any disadvantages with regard to function or

  4. Incidencia y factores de riesgo de la fractura de fémur proximal por osteoporosis Incidence of and risk factors associated with fractures of the proximal femur due to osteoporosis

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    María Teresa Mosquera

    1998-04-01

    Full Text Available Todos los años se producen en el mundo más de un millón de fracturas de fémur proximal, sobre todo en personas de edad avanzada. Dado el continuo envejecimiento de las poblaciones, las fracturas aumentarán año tras año y constituirán un problema cada vez más grave de salud pública. Se espera que el mayor aumento de dichas fracturas ocurra en América Latina alrededor del 2050. Teniendo en cuenta que cerca de 70% de las fracturas atraumáticas en personas mayores de 45 años de edad se deben a osteoporosis, se diseñó un estudio de casos y controles en la ciudad de Mar del Plata, Argentina, para conocer la incidencia de fracturas de fémur proximal por osteoporosis y los factores de riesgo asociados. Entre el 1 de agosto de 1992 y el 31 de julio de 1993 se registraron todos los casos de fracturas de fémur proximal por osteoporosis en personas mayores de 50 años de edad que acudieron a cualquiera de los 30 centros de salud públicos y privados de la ciudad. Se registró un total de 246 casos. La tasa de incidencia por 100 000 habitantes en la población mayor de 50 años fue de 259 en mujeres y de 92 en varones, con una relación de 2,8:1. La incidencia fue siempre mayor a mayor edad y sobre todo a partir de los 75 años. Los factores asociados con aumento del riesgo de fractura de fémur proximal con significación estadística fueron: antecedentes de enfermedades neurológicas, consumo de psicofármacos, consumo de alcohol, fracturas previas, enfermedades cardiovasculares y menor consumo de lácteos. No se observaron diferencias entre los casos y los controles con respecto a edad de inicio de la menopausia, peso, talla, actividad previa, hábito de fumar o exposición al sol, como así tampoco en el porcentaje de mujeres que habían tenido ooforectomías.Every year more than one million fractures of the proximal femur occur in the world, especially in older persons. Given the continuous aging experienced by populations, such

  5. The impact of care pathways for patients with proximal femur fracture: rationale and design of a cluster-randomized controlled trial

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    Vanhaecht Kris

    2012-05-01

    Full Text Available Abstract Background Proximal femur fracture (PFF is associated with considerable morbidity and mortality. The European Quality of Care Pathway (EQCP study on PFF (NCT00962910 was designed to determine how care pathways (CP for hospital treatment of PFF affect consistency of care, adherence to evidence-based key interventions, and clinical outcome. Methods/Design An international cluster-randomized controlled trial (cRCT will be performed in Belgium, Ireland, Italy and Portugal. Based on power analyses, a sample of 44 hospital teams and 437 patients per arm will be included in the study. In the control arm, usual care will be provided. Experimental teams will implement a care pathway which will include three active components: a formative evaluation of quality and organization of the care setting, a set of evidence-based key interventions, and support of the development and implementation of the CP. Main outcome will be the six-month mortality rate. Discussion The EQCP study constitutes the first international cRCT on care pathways. The EQCP project was designed as both a research and a quality improvement project and will provide a real-world framework for process evaluation to improve our understanding of why and when CP can really work. Trial registration number NCT00962910

  6. COMPARATIVE STUDY BETWEEN PROXIMAL FEMORAL NAILING AND DYNAMIC HIP SCREW IN THE MANAGEMENT OF INTERTROCHANTERIC FRACTURES OF FEMUR

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    Penugonda Ravi Shankar

    2015-01-01

    Full Text Available AIMS AND OBJECTIVES : To determine the rate of union, complications, operative risks and functional outcomes in intertrochanteric fractures treated with DHS and PFN , To compare the results obtained and To compare the effectiveness of DHS and PFN in treatment of intertrochanteric fractures. RESULTS : In the present series of 24 cases of Intertrochanteric fractures were treated by proximal femoral nailing and dynamic hip screw, 12 cases in each. Out of 24 there were 13 male and 11 female. Minimum age was 36 years, maximum age 76 years with mean age of 59.25 years. Slip and fall accounted for 75% of cases. BOYD and GRIFFIN type II fracture accounted for 58.3% of cases. Mean duration of hospital stay was 26 days in both PFN and DHS groups. Length of incision was small 5 - 6cm in PFN group compared to 10 - 12cm in DHS group. Mean external blood loss 150ml in PFN group and 315 ml in DHS group. Mean time for full weight bearing was 11.5 weeks for PFN group and 14.3 weeks for DHS group. Radiological union was 12.3 weeks in PFN group and 15.5 weeks in DHS group. Good to excellent results were seen in 91.7% of cases in PFN group and 75% in DHS group. CONCLUSION : From the study, we consider PFN as better alternative to DHS in the treatment of intertrochanteric fractures but is technically difficult procedure and requires more expertise compared to DHS.As learning curve of PFN procedure is steep, with experience gained from each case operative time, radiation exposure and intraoperative complications can be reduced in each case of PFN

  7. INTERTAN nail versus proximal femoral nail antirotation-Asia for intertrochanteric femur fractures in elderly patients with primary osteoporosis.

    Science.gov (United States)

    Zhang, Hui; Zeng, Xianshang; Zhang, Nan; Zeng, Dan; Xu, Ping; Zhang, Lili; Chen, Deng; Yu, Weiguang; Zhang, Xinchao

    2017-08-01

    Objectives To compare the long-term functional and radiographic outcomes of the proximal femoral nail antirotation-Asia (PFNA-II) and INTERTAN nail (IT) in the management of intertrochanteric femoral fractures (IFFs) (AO/OTA Type 31A1.1-A2.3) in elderly patients with primary osteoporosis. Methods A retrospective comparative study was performed in our institution. From January 2009 to March 2012, 243 patients with osteoporosis (243 hips) with IFFs (AO/OTA Type 3.1A1.1-A2.3) underwent repair with either a PFNA-II or IT. Follow-up assessments were performed 1, 3, 6, 9, and 12 months postoperatively and every year thereafter. All implant position changes were noted. Patient-related functional outcomes were evaluated based on the Harris hip score. Results In total, 174 patients with osteoporosis (IT, n = 86; PFNA-II, n = 88) were evaluated during a mean follow-up period of 40 months (range, 38-60 months). An increased risk of femoral shaft fracture after implant removal was observed at month 9 of follow-up in 0.0% and 4.4% of the IT and PFNA-II groups, respectively. This difference remained over time with rates of 1.1% and 6.8%, respectively, at the last follow-up. Conclusion The IT nail appears to be a reliable implant in the management of IFFs (AO/OTA Type 3.1A1.1-A2.3) in elderly patients with primary osteoporosis.

  8. Assessment of the geometry of proximal femur for short cephalomedullary nail placement: An observational study in dry femora and living subjects

    Science.gov (United States)

    Pathrot, Devendra; Ul Haq, Rehan; Aggarwal, Aditya N; Nagar, Mahindra; Bhatt, Shuchi

    2016-01-01

    Background: Intramedullary devices have increasingly become popular and are widely used for fixation of unstable intertrochanteric and subtrochanteric fractures. These implants have been designed taking into consideration of the anthropometry of the western population which varies from those of other ethnic groups. This study was carried out to assess the geometry of proximal femur for the placement of short cephalomedullary nails in our subset of patients and suggest suitable design modifications based on these parameters. Materials and Methods: The study was conducted in the following three groups: (1) Anthropometric study of 101 adult human dry femora, (2) radiographs of the same femora, and (3) radiographs of the contralateral uninjured limb of 102 patients with intertrochanteric or subtrochanteric fractures. In Group 1, standard anthropometric techniques were used to measure neck shaft angle (NSA), minimal neck width (NW), trochanteric offset, and distance from the tip of greater trochanter (GT) to the lower border of lesser trochanter on the femoral shaft axis (distance X). In Group 2 and 3, the NSA, minimal NW, NW at 130° and 135°, trochanteric shaft angle (TSA), trochanteric offset, distance X, distance between the tip of GT and the point where the neck axis crosses the line joining the tip of the GT to the lower border of the lesser trochanter on the femoral shaft axis (distance Y), and canal width at 10, 15, and 20 cm from tip of GT were measured on standard radiographs. The values obtained in these three groups were pooled to obtain mean values. Various parameters of commonly used short cephalomedullary nails available for fixation of pertrochanteric fractures were obtained. These were compared to the results obtained to suggest suitable modifications in the nail designs for our subset of patients. Results: The mean parameters observed were as follows: NSA 128.07° ± 4.97 (range 107°–141°), minimum NW 29.0 ± 2.8 mm (range 22–42 mm), NW at 130

  9. Assessment of the geometry of proximal femur for short cephalomedullary nail placement: An observational study in dry femora and living subjects

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    Devendra Pathrot

    2016-01-01

    Full Text Available Background: Intramedullary devices have increasingly become popular and are widely used for fixation of unstable intertrochanteric and subtrochanteric fractures as well. These implants have been designed taking into consideration the anthropometry of the western population whose anthropometry varies from those of other ethnic groups. This study was carried out to assess the geometry of proximal femur for the placement of short cephalomedullary nails in our subset of patients and suggest suitable design modifications based on these parameters. Materials and Methods: The study was conducted in the following three groups: (1 Anthropometric study of 101 adult human dry femora, (2 radiographs of the same femora, and (3 radiographs of the contralateral uninjured limb of 102 patients with intertrochanteric or subtrochanteric fractures. In Group 1, standard anthropometric techniques were used to measure neck shaft angle (NSA, minimal neck width (NW, trochanteric offset, and distance from the tip of greater trochanter (GT to the lower border of lesser trochanter on the femoral shaft axis (distance X. In Group 2 and 3, the NSA, minimal NW, NW at 130° and 135°, trochanteric shaft angle (TSA, trochanteric offset, distance X, distance between the tip of GT and the point where the neck axis crosses the line joining the tip of the GT to the lower border of the lesser trochanter on the femoral shaft axis (distance Y, and canal width at 10, 15, and 20 cm from tip of GT were measured on standard radiographs. The values obtained in these three groups were pooled to obtain mean values. Various parameters of commonly used short cephalomedullary nails available for fixation of pertrochanteric fractures were obtained. These were compared to the results obtained to suggest suitable modifications in the nail designs for our subset of patients. Results: The mean parameters observed were as follows: NSA 128.07° ± 4.97 (range 107°–141°, minimum NW 29.0 ± 2.8 mm

  10. Frequency of Osteoporosis and Osteopenia According To Bone Mineral Density of Proximal Femur Subregions in Normal and Osteopenic Postmenopausal Women With Respect to Total Hip Bone

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    Murat Ersöz

    2002-09-01

    Full Text Available In this study 29 normal (mean age: 65.6 ± 5.1 years and 33 osteopenic (mean age: 67.6 ± 4.9 years postmenopausal women according to total bone mineral density (BMD of the hip were evaluated for BMD values of subregions of proximal femur. The percentages for osteoporosis and osteopenia with respect to subregions were 13.8% and 58.6% for femoral neck and 20.7% and 41.4% for Ward’s triangle in normal group. In trochanteric and intertrochanteric measurements there were no T scores below –2.5 but 17.2% of the subjects were osteopenic with regard to trochanteric and 6.9% were osteopenic due to intertrochanteric BMD values. The percentages for osteoporosis and osteopenia with respect to subregion measurements were 57.6% and 42.4% for femoral neck, 60.6% and 36.4% for Ward’s triangle, 3% and 78.8% for trochanteric, 9.1% and 87.9% for intertrochanteric regions in osteopenic group according to total hip values. Knowing that hip fracture risk is increasing 2-3 fold for 1 standart deviation decrease from the young adult mean value for all subregions and knowing the relation between cervical hip fractures and BMD values of Ward’s triangle and femoral neck and the relation between intertrochanteric fractures and trochanteric BMD values, it is recommended to evaluate the BMD values of subregions of the hip besides the total hip values in daily practice.

  11. Distribution of bone density in the proximal femur and its association with hip fracture risk in older men: the osteoporotic fractures in men (MrOS) study.

    Science.gov (United States)

    Yang, Lang; Burton, Annabel C; Bradburn, Mike; Nielson, Carrie M; Orwoll, Eric S; Eastell, Richard

    2012-11-01

    This prospective case-cohort study aimed to map the distribution of bone density in the proximal femur and examine its association with hip fracture. We analyzed baseline quantitative computed tomography (QCT) scans in 250 men aged 65 years or older, which comprised a randomly-selected subcohort of 210 men and 40 cases of first hip fracture during a mean follow-up period of 5.5 years. We quantified cortical, trabecular, and integral volumetric bone mineral density (vBMD), and cortical thickness (CtTh) in four quadrants of cross-sections along the length of the femoral neck (FN), intertrochanter (IT), and trochanter (TR). In most quadrants, vBMDs and CtTh were significantly (p fracture, we merged the two quadrants in the medial and lateral aspects of the FN, IT, and TR. At most sites, QCT measurements were associated significantly (p fracture, the hazard ratio (HR) adjusted for age, body mass index (BMI), and clinical site for a 1-SD decrease ranged between 2.28 (95% confidence interval [CI], 1.44-3.63) to 6.91 (95% CI, 3.11-15.53). After additional adjustment for total hip (TH) areal BMD (aBMD), trabecular vBMDs at the FN, TR, and TH were still associated with hip fracture significantly (p fracture significantly (p > 0.05) better than TH aBMD. With an area under the receiver operating characteristic curve (AUC) of 0.901 (95% CI, 0.852-0.950), the regression model combining TH aBMD, age, and trabecular vBMD predicted hip fracture significantly (p fracture risk and highlight trabecular vBMD at the FN and TR as an independent risk factor. Copyright © 2012 American Society for Bone and Mineral Research.

  12. The analysis of densitometric and geometric parameters of bilateral proximal phalanges in horses with the use of peripheral quantitative computed tompgraphy

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    Dzierzęcka Małgorzata

    2012-07-01

    Full Text Available Abstract Background Proximal phalanges in horses are among bones that are most prone to injuries. So far, the detailed analysis of densitometric and geometric parameters of both front legs proximal phalanges in horses has not been investigated. The aim of this study was to compare the densitometric and geometric parameters between proximal phalanges in equine both front legs with the use of peripheral quantitative computed tomography (pQCT. Methods The study material comprised isolated both front legs proximal phalanges derived from 22 horses. The structure analysis of the proximal phalanges was conducted with the pQCT. The following bone parameters were determined: bone mineral content, volumetric bone mineral density, total bone area, trabecular area, cortical area, cortical thickness, periosteal circumference, endocortical circumference, Strength Strain Index. Tomographic analysis of proximal phalanges was conducted at three levels: at 15%, 50% and 85% of the bone length. Results The statistical analysis showed that both the densitometric and geometric parameters of the bone at 50% and 85% of its length, did not present any statistically significant differences for the left or right proximal phalanges of the forelimb. At the same time, all examined parameters measured at 15% of the bone length, in the vicinity of the proximal metaphysis revealed significant statistical differences between both front legs proximal phalanges. Conclusions The proximal phalanx parameters in the forelimbs are significantly different for the left and right proximal phalanx at 15% of the length and they indicate higher Strength Strain Index of the left bone in this location. The densitometric and geometric parameters of the bone at 50% and 85% of its length, did not present any statistically significant differences for the left or right proximal phalanges of the left and right forelimbs. The most serious changes caused by asymmetrical load of the thoracic limbs in

  13. Effect of intertrochanteric osteotomy on the proximal femur of rabbits: assessment with power Doppler sonography and scintigraphy Efeito da osteotomia intertrocantérica no femur proximal de coelhos: avaliação com utra-sonografia power Doppler e cintilografia

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    Andrea S. Doria

    2007-01-01

    Full Text Available OBJECTIVE: In bone injury, repair results in local increased vascularity and bone marrow remodeling. Characterizing the vascular and metabolic imaging patterns of the proximal femur following an intertrochanteric osteotomy may help clinicians decide proper management of the patient. Our objective was to measure Doppler sonography and scintigraphy interval changes in the proximal femur following intertrochanteric osteotomy and compare imaging and histomorphometric measurements in the late post-operative stage (6 weeks after surgery in a rabbit model of bone injury. MATERIALS AND METHODS: Both hips of 12 adult rabbits were imaged with power Doppler sonography and scintigraphy prior to and after (7 days and 6 weeks unilateral osteotomy. Accuracy of the imaging methods was evaluated using hip operative status and histomorphometric results (vascular fractional area and number of vessels per area unit as reference standard measures. RESULTS: A significant difference in the mean number of pixels was noted between operated and non-operated femura in late post-operative power Doppler examinations (P=0.049. Although without reaching statistical significance, the AUC of Doppler measurements (AUC=0.99 was numerically greater than the AUC of scintigraphy measurements (AUC=0.857±0.099 (P=0.15 in differentiating proximal femura with regard to their fractional vascular areas in the late post-operative stage. In contrast, scintigraphy tended to perform better (AUC=0.984±0.022 than Doppler ultrasound (AUC=0.746±0.131 to demonstrate the vascularity intensity per area unit (P=0.07 in the late stage. CONCLUSION: Our results warrant further investigation to determine the value of different imaging modalities for assessment of pathologic changes following hip surgery. Power Doppler sonography demonstrated larger AUCs (representing higher accuracy for the discrimination of vascular fractional areas and scintigraphy, for discrimination of the number of vessels per

  14. Pulsed electromagnetic fields for postmenopausal osteoporosis and concomitant lumbar osteoarthritis in southwest China using proximal femur bone mineral density as the primary endpoint: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Liu, Hui-Fang; He, Hong-Chen; Yang, Lin; Yang, Zhou-Yuan; Yao, Ke; Wu, Yuan-Chao; Yang, Xi-Biao; He, Cheng-Qi

    2015-06-10

    Osteoporosis (OP) and osteoarthritis (OA) are prevalent skeletal disorders among postmenopausal women. Coexistence is common especially that of postmenopausal osteoporosis (PMO) and lumbar OA. An hypothesis has been raised that OP and OA might share the same pathogenic mechanism, and pulsed electromagnetic fields (PEMFs) were reported to have anti-osteoporosis and anti-osteoarthritis properties, but this suggestion was based primarily on biomarker data. Therefore, whether these two effects could take place simultaneously has not yet been investigated. This randomized controlled trial (RCT) is designed to explore the effect of PEMFs for PMO and concomitant lumbar OA. The study will include PMO patients (postmenopausal women; aged between 50 and 70 years; have been postmenopausal for at least 5 years and diagnosed with OP using proximal femur T-score) with concomitant lumbar OA (patients with confounding disorders like diabetes, hypertension, hyperlipidemia, and previous fracture history, etcetera, will be excluded) will be randomly assigned to two arms: PEMFs group and sham PEMFs group. There will be 25 participants in each arm (50 in total) and the outcome assessment, including the primary endpoint (proximal femur bone mineral density), will be performed at 5 weeks, 3 months and 6 months after enrollment. PMO and lumbar OA are prominent public health problem, especially for postmenopausal women. We hope this RCT will provide scientific evidence to primary care of the postmenopausal women regarding the use of these nonpharmaceutical, noninvasive modalities, PEMFs, in managing PMO and lumbar OA. Chinese Clinical Trial Registry: ChiCTR-TRC-14005156 (28 August 2014).

  15. "Death by a thread"--peritonitis due to visceral perforation by a guide wire, during proximal femur osteosynthesis with DHS: a fatal case and legal implications.

    Science.gov (United States)

    Durão, Carlos; Barros, André; Guerreiro, Rui; Pedrosa, Frederico

    2015-04-01

    Iatrogenic intestinal perforations in orthopaedic surgery are very rare. Reports of iatrogenic lesions caused by a guide wire during femur fracture osteosynthesis are even scarcer. There are no similar reports in recent literature. As opposed to what is normally described the lesion documented in this case report was not identified on time resulting in death by peritonitis. The forensic autopsy allowed the identification of an intestinal perforation with faecal leakage to peritoneal space in association with a vesical perforation enabling the reproduction of the guide wire path. In view of the increasing number of osteosynthesis it is essential for the surgeon to be aware of possible complications due to guide wire perforations. Cases like this go unnoticed if the forensic pathologist is not familiarized with the surgical technique which may explain the rarity of such descriptions in literature. Copyright © 2015. Published by Elsevier Ireland Ltd.

  16. The effects of necrotic lesion size and orientation of the femoral component on stress alterations in the proximal femur in hip resurfacing - a finite element simulation.

    Science.gov (United States)

    Tai, Ching-Lung; Chen, Yung-Chou; Hsieh, Pang-Hsin

    2014-08-05

    Due to the advantages of its bone-conserving nature, hip resurface arthroplasty (HRA) has recently gained the interest of orthopedic surgeons for the treatment of young and active patients who have osteonerosis of the femoral head. However, in long-term follow-up studies after HRA, narrowing of the femoral neck has often been found, which may lead to fracture. This phenomenon has been attributed to the stress alteration (stress shielding). Studies addressing the effects of necrotic size and the orientation of the implant on stress alterations are lacking. Computed tomography images of a standard composite femur were used to create a three-dimensional finite-element (FE) intact femur model. Based on the intact model, FE models simulating four different levels of necrotic regions (0°, 60°, 100°, 115°) and three different implant insertion angles (varus 10°, neutral, valgus 10°) were created. The von Mises stress distributions and the displacement of the stem tip of each model were analyzed and compared for loading conditions that simulated a single-legged stance. Stress shielding occurred at the femoral neck after HRA. More severe stress shielding and an increased displacement of the stem tip were found for femoral heads that had a wider necrotic lesion. From a biomechanics perspective, the results were consistent with clinical evidence of femoral neck narrowing after HRA. In addition, a varus orientation of the implant resulted in a larger displacement of the stem tip, which could lead to an increased risk of implant loosening. A femoral head with a wide necrotic lesion combined with a varus orientation of the prosthesis increases the risk of femoral neck narrowing and implant loosening following HRA.

  17. Quantitative CT assessment of proximal femoral bone density. An experimental study concerning its correlation to breaking load for femoral neck fractures; Quantitative CT des proximalen Femurs. Experimentelle Untersuchungen zur Korrelation mit der Bruchlast bei Schenkelhalsfrakturen

    Energy Technology Data Exchange (ETDEWEB)

    Buitrago-Tellez, C.H.; Schulze, C.; Gufler, H.; Langer, M. [Abt. Roentgendiagnostik, Radiologische Universitaetsklinik, Albert-Ludwigs-Univ. Freiburg (Germany); Bonnaire, F.; Hoenninger, A.; Kuner, E. [Abt. Unfallchirurgie, Chirurgische Universitaetsklinik, Albert-Ludwigs-Univ. Freiburg (Germany)

    1997-12-01

    Purpose: In an experimental study, the correlation between the trabecular bone density of the different regions of the proximal femur and the fracture load in the setting of femoral neck fractures was examined. Methods: The bone mineral density 41 random proximal human femora was estimated by single-energy quanitative CT (SE-QCT). The trabecular bone density was measured at the greatest possible extracortical volume at midcapital, midneck and intertrochanteric level and in the 1 cm{sup 3} volumes of the centres of these regions in a standardised 10 mm thick slice in the middle of the femoral neck axis (in mg/ml Ca-hydroxyl apatite). The proximal femora were then isolated and mounted on a compression/bending device under two-legged stand conditions and loaded up to the point when a femoral neck fracture occurred. Results: Statistical analysis revealed a linear correlation between the trabecular bone density and the fracture load for the greater regions, with the highest value in the maximal area of the head (coefficient factor r=0.76). Conclusion: According to our data, the measurement of the trabecular bone by SE-QCT at the femoral head is a more confident adjunct than the neck or trochanteric area to predict a femoral neck fracture. (orig.) [Deutsch] Ziel: In einer experimentellen Versuchsserie wurde der Zusammenhang zwischen der Knochendichte an verschiedenen Lokalisationen des proximalen Femurs und der maximalen Last bei der Entstehung von Schenkelhalsfrakturen (Bruchlast) untersucht. Methode: An 41 frisch entnommenen proximalen Leichenfemora wurde die trabekulaere Knochendichte mit Hilfe der Ein-Energie Quantitativen Computertomographie (SE-QCT) bei einer Schichtdicke von 10 mm in der Mitte der Schenkelhalsachse bestimmt. Erfasst wurden die maximale extrakortikale, zylinderfoermige Messregion im Hueftkopf, Schenkelhals und der Intertrochantaerregion sowie das 1 cm{sup 3} umfassende Zentrum dieser Regionen. Die Praeparate wurden unter Zweibeinstandbedingungen

  18. Correlação entre tempo para o tratamento cirúrgico e mortalidade em pacientes idosos com fratura da extremidade proximal do fêmur Correlation between time until surgical treatment and mortality among elderly patients with fractures at the proximal end of the femur

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    Gustavo Gonçalves Arliani

    2011-04-01

    Full Text Available OBJETIVO: O objetivo primário do estudo é analisar a possível associação entre o atraso para a realização do tratamento cirúrgico e mortalidade em pacientes idosos com fratura da extremidade proximal do fêmur. MÉTODOS: Foram estudados 269 pacientes com fraturas da extremidade proximal do fêmur (fraturas do colo do fêmur e fraturas intertrocanterianas, tratadas cirurgicamente no Hospital São Paulo - Unifesp-SP, no período de janeiro de 2003 a dezembro de 2007. Foram analisados e comparados com a literatura referente ao assunto os seguintes atributos: sexo, idade, tipo de fratura, classificação da mesma, lado acometido, síntese utilizada, mecanismo de trauma, tempo de internação, tempo para cirurgia, comorbidades associadas, hemograma de entrada, tipo de anestesia, necessidade de transfusão sanguínea, dia da semana e estação do ano da fratura. RESULTADOS: O estudo apresentou correlação entre maior número de comorbidades clínicas, maior tempo de internação e utilização de anestesia geral na cirurgia com maior mortalidade dos pacientes. CONCLUSÃO: Não houve associação entre tempo para realização da cirurgia e mortalidade.OBJECTIVE: The primary aim of this study was to analyze the possible association between delay in receiving surgical treatment and mortality among elderly patients with fractures at the proximal end of the femur. METHODS: 269 patients with fractures at the proximal end of the femur (femur neck and intertrochanteric fractures who were treated surgically at Hospital São Paulo, UNIFESP, São Paulo, between January 2003 and December 2007, were studied. Sex, age, type of fracture, classification of the fracture, affected side, synthesis used, trauma mechanism, length of hospitalization, length of surgery, associated comorbidities, hemogram at admission, type of anesthesia, need for blood transfusion, day of the week and season of the year of the fracture were analyzed and compared with the literature

  19. Relationships of trabecular bone structure with quantitative ultrasound parameters: in vitro study on human proximal femur using transmission and backscatter measurements.

    Science.gov (United States)

    Padilla, F; Jenson, F; Bousson, V; Peyrin, F; Laugier, P

    2008-06-01

    The present study was designed to assess the relationships between QUS parameters and bone density or microarchitecture on samples of human femoral trabecular bone. The normalized slope of the frequency-dependent attenuation (nBUA), the speed of sound (SOS) and the broadband ultrasound backscatter coefficient (BUB) were measured on 37 specimens of pure trabecular bones removed from upper parts of fresh human femurs. Bone mineral density (BMD) was assessed using a clinical scanner. Finally, 8 mm diameter cylindrical cores were extracted from the specimens and their microarchitecture was reconstructed after synchrotron radiation microtomography experiments (isotropic resolution of 10 microm). A large number of microarchitectural parameters were computed, describing morphology, connectivity and geometry of the specimens. BMD correlated with all the microarchitectural parameters and the number of significant correlations was found among the architectural parameters themselves. All QUS parameters were significantly correlated to BMD (R=0.83 for nBUA, R=0.81 for SOS and R=0.69 for BUB) and to microarchitectural parameters (R=-0.79 between nBUA and Tb.Sp, R=-0.81 between SOS and Tb.Sp, R=-0.65 between BUB and BS/BV). Using multivariate model, it was found that microstructural parameters adds 10%, 19%, and 4% to the respective BMD alone contribution for the three variables BUA, SOS and BUB. Moreover, the RMSE was reduced by up to 50% for SOS, by up to 21% for nBUA and up to 11% when adding structural variables to BMD in explaining QUS results. Given the sample, which is not osteoporosis-enriched, the added contribution is quite substantial. The variability of SOS was indeed completely explained by a multivariate model including BMD and independent structural parameters (R(2)=0.94). The inverse problem on the data presented here has been addressed using simple and multiple linear regressions. It was shown that the predictions (in terms of R(2) or RMSE) of microarchitectural

  20. Proximal femur geometry in the adult Kenyan femur and its ...

    African Journals Online (AJOL)

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  1. Efeitos do treinamento físico sobre a resistência mecânica do terço proximal do fêmur de ratos Effects of physical training on the mechanical resistance of rat femur proximal thirds

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    Andreo Fernando Aguiar

    2010-01-01

    Full Text Available OBJETIVO: Analisar o comportamento mecânico do terço proximal do fêmur de ratos submetidos ao treinamento aeróbio e resistido crônicos. MÉTODOS: Ratos Wistar machos (80 dias, 300 a 350 g foram divididos em 3 grupos (n=8 por grupo: Treinamento aeróbio/8 semanas (TA, Treinamento resistido/8 semanas (TR e controle/8 semanas (CO. Ao término do período de treinamento os animais foram sacrificados e o fêmur direito coletado. Para análise do comportamento mecânico do fêmur foram realizados ensaios de flexo-compressão. RESULTADOS: O treinamento resistido ocasionou redução significante da força máxima (Fmáx do fêmur. Por outro lado, promoveu um aumento (23,7% relevante, porém não significante, da deformação da força máxima (DFmáx. O treinamento aeróbio não afetou a Fmáx, porém promoveu uma redução (26,6% considerável, também não significante, da DFmáx. CONCLUSÕES: Os resultados demonstram que o treinamento resistido e aeróbio, promoveram redução da Fmáx e da DFmáx óssea, respectivamente. Os dados evidenciam uma ação diferencial de ambos os modelos de treinamento físico sobre as propriedades mecânicas do fêmur de ratos.OBJECTIVE: To analyze the mechanical behavior of rat femur proximal thirds submitted to chronic aerobic and resistance training. METHODS: Male Wistar rats (80 days of age, weighing 300 to 350 g were divided into 3 groups (n=8 per group: control (CO, aerobic training (TA and resistance training (TR. At the end of the training, the animals were euthanized and the right femur was collected. Flexion-compression tests were carried out to analyze the mechanical behavior of the femurs. RESULTS: The resistance training promoted a significant reduction in maximum force (Fmáx of the femur. However, it also promoted a relevant increase (23.7%, though without statistical significance, in maximum force deformation (DFmáx. The aerobic training did not affect maximum force, however, it caused a

  2. Femur fracture repair - discharge

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000166.htm Femur fracture repair - discharge To use the sharing features on this page, please enable JavaScript. You had a fracture (break) in the femur in your leg. It ...

  3. The effect of an external hip joint stabiliser on gait function after surgery for tumours located around the circumference of the pelvis: analysis of seven cases of internal hemipelvectomy or proximal femur resection.

    Science.gov (United States)

    Akiyama, Toru; Saita, Kazuo; Ogura, Koichi; Kawai, Akira; Imanishi, Jungo; Yazawa, Yasuo; Kawashima, Noritaka; Ogata, Toru

    2016-03-01

    Limb-sparing resection of malignant pelvic tumours provides the opportunity for patients to obtain better post-operative mobility. However, because few studies have examined in detail the gait function of patients following pelvic tumour resection, the factors affecting gait performance remain to be clarified. Here, with the laboratory-based computer-assisted gait analysis, we evaluated these patients' gait objectively and the impact of a hip-stabilising supporter on gait improvement was simultaneously examined. Three-dimensional gait analysis was performed to obtain cross-sectional data for seven post-operative patients (mean age, 42.7 years; range, 20-61 years) who underwent various types of resection, including P1/4 internal hemipelvectomy (IH), P1/2/3 IH, and proximal femur resection with prosthetic reconstruction. To assess the immediate effects of a hip joint stabiliser, we instructed subjects to walk at their self-selected preferred speed and compared gait parameters with and without use of the hip stabiliser. At baseline, the average walking speed was 0.75 m/s (95% CI 0.53-0.97). As shown by the intra-subject comparison, the hip stabiliser increased walking speed in all but one subject, increasing both temporal and spatial parameters. Ground reaction force of operated limbs increased for some subjects, while step length increased on at least one side in all subjects. Improvement in the gait parameters is indicative of better control provided by the external hip stabiliser over the affected limb. Moreover, our findings show the potential of a biomechanical approach to improve gait function following pelvic tumour resection.

  4. Avaliação do emprego da haste femoral curta na fratura trocantérica instável do fêmur Evaluating the use of a proximal femoral nail in unstable trochanteric fracture of the femur

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    João Antonio Matheus Guimarães

    2008-09-01

    , devido a uma redução inadequada em varo, ocorreu um cutout que necessitou de revisão cirúrgica. Outro caso de fratura do tipo 31A2, evoluiu para necrose avascular da cabeça femoral, após consolidação da fratura. Por fim, um caso de fratura do tipo 31A3, devido a redução inadequada no plano sagital, evoluiu para retarde de consolidação, com quebra da haste após 13 meses da cirurgia. CONCLUSÃO: A osteossíntese com haste proximal, como tratamento da fratura trocantérica instável do fêmur realizada em pacientes com idade superior a 60 anos, resultou na consolidação da maioria dos casos. As complicações foram distintas nos dois subgrupos estudados. A redução adequada da fratura antes da introdução da haste intramedular é fundamental para o sucesso do procedimento.OBJECTIVE: Identifying the rate of healing of unstable trochanteric fractures submitted to osteosynthesis with a proximal femoral nail (PFN® - AO/ASIF, in patients operated on between November 1999 and March 2004. METHODS: 45 patients were analyzed, ages ranging from 60 to 93, with unstable trochanteric fractures of the femur submitted to osteosynthesis with short PFN®, with indirect reduction in a traction device guided by radioscopy. The fractures were classified according to the AO/OTA classification. Bone quality was evaluated by the Singh index in the post-operative radiographic routine. The quality of the reduction achieved and the positioning of the implant were evaluated by post-operative anteroposterior and profile X-ray of the proximal femur, with analysis of the cervicodiaphyseal angle and the distance between the tip of the sliding nail and the center of the femoral head, the so-called "tip apex distance" (TAD. RESULTS: The mean age of patients studied was 80.8 years (60-93. Females prevailed, with 37 cases (82.2%. The right side was involved in 22 cases (48.89% and the left side, in 23 (51.1%. All fractures were unstable, 22 of them of the type 31A2 (48.8%, and 23, of the

  5. The effectiveness of the implementation of new technologies in the prevention of purulent complications of repeated surgеries for complications of fractures of the proximal femur of patients

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    An. V. Kalashnikov

    2016-06-01

    Full Text Available Despite the latest achievements of modern traumatology, remains quite high percentage of unsatisfactory results of treatment of fractures of the proximal femur (fPf. According to the literature repeated surgery increases the risk of postoperative purulent complications in several times. The authors of the article developed the innovations introduced in practice based on the use of thrombocytopoiesis fibrin gel, which has a high antibacterial activity due to preservation of leukocytes (local antibiotic effect, together with bone shavings during the performing of the operations when performing reactioneze and TEP after performing osteosynthesis, and also at persons of senile and elderly, for prevention of postoperative purulent complications in fPf. A comprehensive clinical study of 120 patients with fPf complications (false joints, aseptic necrosis of the femoral head, axial deformation after osteomyelitis who underwent re-operative intervention was provided. Patients were divided into two groups, first (control group consisted of 60 patients with consequences fPf who underwent total endoprosthesis (TEP of the hip joint (30 patients and locked intramedullary nailing (LIN (30 patients by conventional methods. The second (experimental group consisted of 60 patients with consequences fPf who underwent TEP of the hip joint (30 patients and LIN (30 patients with use developed by authors of innovations. Effectiveness of prevention of septic complications in both groups of observation was evaluated. The observation period was 1 year. There was statistically significant (p≤0.01 decrease in the number of early (4 times and late (3 times postoperative complications in patients of the experimental group in comparison with patients of control group. The new technologies use allows to increase in 8.4% the efficiency of preventive maintenance of purulent complications of surgical treatment of patients with complications after performing osteosynthesis in the

  6. Análisis numérico comparativo de fijadores para el tratamiento de fracturas proximales del fémur // Comparative numerical analysis of fixers for the treatment of proximal fractures of the femur

    Directory of Open Access Journals (Sweden)

    Jorge Bosch-Cabrera

    2011-08-01

    Full Text Available ResumenMúltiples son los dispositivos utilizados para lograr la consolidación de las fracturas proximales delfémur, algunos sufren roturas antes de ser retirados del paciente, ocasionando nuevascomplicaciones al mismo. En esta investigación se presentan los resultados del análisis numéricorealizado a un fijador interno del tipo placa DHS (Dinámic Hip Screw y a un fijador externomonolateral con tornillo cefálico RALCA (Rodrigo Álvarez Cambras, con el propósito de determinarel comportamiento del estado tensional-deformacional de ambos dispositivos durante laconsolidación ósea de fracturas proximales de cadera, bajo la marcha monopodal del paciente. Parala modelación geométrica de los dispositivos en cuestión se empleó el paquete de diseño en 3DSolidWorks y la simulación numérica se realizó con el empleo del paquete de análisis por elementosfinitos Cosmos/Works. Los resultados muestran valores inferiores de las tensiones máximas en elfijador externo en comparación con las tensiones que surgen en la placa dinámica bajo la acción delas cargas actuantes en los modelos, por lo que se concluye que el primero posee mejorescaracterísticas resistivas, siendo recomendable su uso en pacientes de mayor peso corporal o quepodrían realizar actividades físicas más activas durante su recuperación postoperatoria.Palabras claves: elementos finitos, biomecánica, osteosíntesis, fractura de cadera.____________________________________________________________________________AbstractMultiple are devices used to achieve the consolidation of proximal femur fractures, some sufferingbreakage before being removed from the patient, causing new complications to them. This researchpresents the results of the numerical analysis made to an internal fixer type plate DHS (Dinámic HipScrew, and to a monolateral external fixer with RALCA (Rodrigo Alvarez Cambras head screw, withthe purpose of determining the behavior of the tensional

  7. Femur Model Reconstruction Based on Reverse Engineering and Rapid Prototyping

    Science.gov (United States)

    Tang, Tongming; Zhang, Zheng; Ni, Hongjun; Deng, Jiawen; Huang, Mingyu

    Precise reconstruction of 3D models is fundamental and crucial to the researches of human femur. In this paper we present our approach towards tackling this problem. The surface of a human femur was scanned using a hand-held 3D laser scanner. The data obtained, in the form of point cloud, was then processed using the reverse engineering software Geomagic and the CAD/CAM software CimatronE to reconstruct a digital 3D model. The digital model was then used by the rapid prototyping machine to build a physical model of human femur using 3D printing. The geometric characteristics of the obtained physical model matched that of the original femur. The process of "physical object - 3D data - digital 3D model - physical model" presented in this paper provides a foundation of precise modeling for the digital manufacturing, virtual assembly, stress analysis, and simulated surgery of artificial bionic femurs.

  8. Avaliação da apresentação de sinais e sintomas de impacto femoroacetabular após epifisiólise do fêmur proximal Evaluation of presentation of signs and symptoms of femoroacetabular impingement after epiphysiolysis of the proximal femur

    Directory of Open Access Journals (Sweden)

    Fábio Peng Krüger

    2011-04-01

    Full Text Available OBJETIVO: Neste trabalho, procuramos avaliar se existe relação entre o grau de deslizamento da epifisiólise femoral proximal (EFP e a presença de impacto femoroacetabular (IFA. Ainda, analisou-se o arco de movimento do quadril (ADM em relação ao IFA, além de revisar a literatura sobre o assunto. MÉTODO: Foram analisados 19 casos de EFP em 15 pacientes tratados cirurgicamente com epifisiodese in situ com um parafuso canulado, com seguimento médio de 27 meses. Realizou-se a análise do grau de deslizamento da EFP pelos ângulos epimetafisário (âEM e coloepifisário (âCE da radiografia em perfil, dos sinais de impacto radiográficos na incidência anteroposterior, dos sintomas clínicos e do ADM do quadril. RESULTADOS: Evidenciou-se que o grau de deslizamento da EFP (através do âEM apresenta relação inversa estatisticamente significante com a presença de IFA no período médio de seguimento deste estudo. Ou seja, os pacientes que demonstraram um quadro sintomático de IFA apresentaram graus menores de deslizamento. Isso pode ser explicado pelo fato que o tipo de impacto que ocorre na EFP (came de inclusão ou de impacção depende do grau de deslizamento, e estes se apresentam de forma e cronologia diferentes. O ADM do quadril não apresentou relação com o IFA. CONCLUSÃO: Há relação entre o grau de deslizamento e a presença de IFA clínicoradiológica após EFP.OBJECTIVES: In this study, we sought to evaluate whether there is any relationship between the degree of epiphysiolysis of the proximal femur (EPF and the presence of femoroacetabular impingement (FAI. Hip range of motion (ROM was also analyzed in relation to FAI, and the literature on this topic was reviewed. METHODS: Nineteen cases of EPF in fifteen patients who had been treated surgically by means of in situ epiphysiodesis with a cannulated screw were evaluated. The mean follow-up was 27 months. The degree of EPF was analyzed using the epimetaphyseal and neck

  9. Numerical Optimization of the Position in Femoral Head of Proximal Locking Screws of Proximal Femoral Nail System; Biomechanical Study.

    Science.gov (United States)

    Konya, Mehmet Nuri; Verim, Özgür

    2017-09-29

    Proximal femoral fracture rates are increasing due to osteoporosis and traffic accidents. Proximal femoral nails are routinely used in the treatment of these fractures in the proximal femur. To compare various combinations and to determine the ideal proximal lag screw position in pertrochanteric fractures (Arbeitsgemeinschaft für Osteosynthesefragen classification 31-A1) of the femur by using optimized finite element analysis. Biomechanical study. Computed tomography images of patients' right femurs were processed with Mimics. Afterwards a solid femur model was created with SolidWorks 2015 and transferred to ANSYS Workbench 16.0 for response surface optimization analysis which was carried out according to anterior-posterior (-10°0) and posterior-anterior directions of the femur neck significantly increased these stresses. The most suitable position of the proximal lag screw was confirmed as the middle of the femoral neck by using optimized finite element analysis.

  10. Prediction of Pathologic Fracture Risk in Activities of Daily Living and Rehabilitation of Patients With Metastatic Breast Carcinoma of the Pelvis and Femur

    National Research Council Canada - National Science Library

    Inoue, Nozomu

    2002-01-01

    The purpose of the project was to develop a computer model of the pelvis and proximal femur which could be used to predict pathologic fracture risk and study the effects of pelvic and proximal femoral...

  11. Osteoporosis and low bone mass at the femur neck or lumbar spine in older adults: United States, 2005-2008

    Science.gov (United States)

    Many current clinical guidelines recommend that assessment of osteoporosis or low bone mass, as defined by the World Health Organization (WHO) (1), be based on bone mineral density at either the femur neck region of the proximal femur (hip) or the lumbar spine (2,3). This data brief presents the mos...

  12. Association of 3D Geometric Measures Derived From Quantitative Computed Tomography With Hip Fracture Risk in Older Men.

    Science.gov (United States)

    Borggrefe, Jan; de Buhr, Timm; Shrestha, Smriti; Marshall, Lynn M; Orwoll, Eric; Peters, Kathy; Black, Dennis M; Glüer, Claus C

    2016-08-01

    We investigated the associations of 3D geometric measures and volumetric bone mineral density (vBMD) of the proximal femur assessed by quantitative computed tomography (QCT) with hip fracture risk among elderly men. This study was a prospective case-cohort design nested within the Osteoporotic Fractures in Men Study (MrOS) cohort. QCT scans of 230 men (65 with confirmed hip fractures) were evaluated with Mindways' QCTPRO-BIT software. Measures that are indicative of bone strength for the femoral neck (FN) and for the trochanteric region (TR) were defined. Bending strength measures were estimated by minimum section modulus, buckling strength by buckling ratio, and a local thinning index (LTI). Integral and trabecular vBMD measures were also derived. Areal BMD (aBMD) of the total proximal femur from dual-energy X-ray absorptiometry (DXA) is presented for comparison. Associations of skeletal measures with incident hip fracture were estimated with hazard ratios (HR) per standard deviation and their 95% confidence intervals (CI) from Cox proportional hazard regression models with adjustment for age, body mass index (BMI), site, and aBMD. Men with hip fractures were older than men without fracture (77.1 ± 6.0 years versus 73.3 ± 5.7 years, p hip fracture risk, independent of aBMD. QCT-derived 3D geometric indices of instability of the proximal femur were significantly associated with incident hip fractures, independent of DXA aBMD. Buckling of the FN is a relevant failure mode not entirely captured by DXA. Further research to study these relationships in women is warranted. © 2016 American Society for Bone and Mineral Research. © 2016 American Society for Bone and Mineral Research.

  13. [Atypical fractures of the femur: apropos of 3 clinical cases].

    Science.gov (United States)

    Sanduloviciu, Maria; Stoll, Delphine; Lamy, Olivier; Krieg, Marc-Antoine; Aubry-Rozier, Bérengère

    2014-08-06

    Osteoporosis is an increasing public health problem. The bisphophonates are the most useful treatment used through the world to prevent osteoporotic fractures. Their large prescription revealed an unpredictable side effect: the atypical fracture. These fractures appear in the subtrochanteric or diaphysal femoral proximal site, spontaneously or after a low trauma, and could be bilateral. X-rays shows a transversal or oblique fracture with a spur in the cortex and with a diffuse thickening of the cortical of the proximal femur. Expert's recommendations are current in progress to well understand and managed this problem. Here we report three cases of atypical femur fractures occurred in our Centre of bone diseases with some management and treatment propositions.

  14. Cesarean Section and Femur Fracture: A Rare Complication

    Directory of Open Access Journals (Sweden)

    Eyup Zengin

    2013-08-01

    Full Text Available Femoral fracture due to birth trauma which is rare, can ocur during cesarean section. This case represents a new born delivered by cesarean section for breech presentation who sustained proximal fracture of the femur. Then newborn was treated with immobilization in bryant traction. Bryant%u2019s traction for 3 weeks in hospital is a safe method for the treatment of femoral fractures in neonates,and the outcome is good.

  15. Emergency treatment of proximal femural fracture within 48h: The

    Directory of Open Access Journals (Sweden)

    Pellegrino Ferrara

    2017-09-01

    Full Text Available Objective: To study the main aspects of osteoporotic emergency fracture of the hip in the Umbria Region in the years 2006-2011. Methods: The study was conducted from January 1 of 2006 to December 31 of 2011, and included only patients over 49 years of age. Patients who did not habitually reside in the region were excluded. They were collected in each based on the following data: age, sex, place of residence (urban or rural, time of the year, fractured side, type of trauma, history of fracture contralateral and perioperative mortality. Results: From 2006 to 2011, a progressive increase in the number of femoral fracture admissions in regional hospitals was observed, equal to 4.73% per annum. The incidence went from 6.8 to 8.1 for 1.000 ultra-65th residents. The most affected age groups are those between 75-84 years and 85- 94 years. Conclusions: The epidemiology of osteoporotic hip fracture in the Umbria Region follows a pattern similar to that of other Italian regions. The in-hospital mortality of these patients is partly determined by age and number of complications they suffer during admission. The impact of economic resources on patients who break the osteoporotic hip justifies the implementation of programs for the prevention of osteoporosis and fractures.

  16. An Osteometric Study of Proximal and Distal Femur Morphology

    Directory of Open Access Journals (Sweden)

    Sema Ozandac

    2015-09-01

    Results: The mean values of these measurements were found to be 22.2 +/- 3.0 mm, 429.5 +/- 35.0 mm, 306.5 +/- 26.7 mm, 61.9 +/- 5.7 mm, 44.2 +/- 3.8 mm, 121.10 +/- 4.00, 30.8 +/- 3.1 and 2.4 +/- 0.2 cm in the right side respectively. However, in the left side same dimensions were 22.5 +/- 4.4 mm, 431.3 +/-26.2 mm, 299.5 +/- 59.4 mm, 61.4 +/- 5.1 mm, 44.2 +/- 3.3 mm, 121.2 +/- 4.00, 30.0 +/- 2.9 and 2.3 +/- 0.2 cm respectively. Conclusion: The observations presented in the report have defined anatomic parameters that need to be taken into consideration when surgical procedures are performed in hip and knee area for this population. [Cukurova Med J 2015; 40(3.000: 466-473

  17. Pre-operative traction for fractures of the proximal femur.

    Science.gov (United States)

    Parker, M J; Handoll, H H G

    2003-01-01

    Pre-operative traction following an acute hip fracture remains standard practice in some hospitals. To evaluate the effects of traction applied to the injured limb prior to surgery for a fractured hip. Different methods of applying traction (skin or skeletal) were considered. We searched the Cochrane Musculoskeletal Injuries Group's specialised register (February 2003), the Cochrane Controlled Trials Register (The Cochrane Library Issue 1, 2003), MEDLINE (1966 to February 2003), EMBASE (1988 to 2003 Week 8), CINAHL (1982 to February 2003), the National Research Register Issue 1, 2003, conference proceedings and reference lists of articles. Date of most recent search: February 2003. All randomised or quasi-randomised trials comparing either skin or skeletal traction with no traction, or skin with skeletal traction for patients with an acute hip fracture prior to surgery. Both reviewers independently assessed trial quality, using a nine item scale, and extracted data. Additional information was sought from all trialists. Wherever appropriate and possible, the data are presented graphically. Eight randomised trials, mainly of moderate quality, involving a total of 1349 predominantly elderly patients, were identified and included in the review. The inclusion in this review update of a newly available trial resulted in no important change in the results or conclusions. Seven trials compared traction with no traction. Although no data pooling was possible, overall these provided no evidence of benefit from traction, either in the relief of pain, ease of fracture reduction or quality of fracture reduction at time of surgery. One of these trials included both skin and skeletal traction groups. This trial and one other compared skeletal traction with skin traction and found no important differences between these two methods, although the initial application of skeletal traction was noted as being more painful and more costly. From the evidence available, the routine use of traction (either skin or skeletal) prior to surgery for a hip fracture does not appear to have any benefit. However, the evidence is also insufficient to rule out the potential advantages for traction, in particular for specific fracture types, or to confirm additional complications due to traction use. Further, high quality trials would be required to confirm or refute the absence of benefits of traction.

  18. Aloenxerto circunferencial de femur proximal em cirurgia de revisäo de artroplastia total de quadril: relato de casos com seguimento mínimo de 20 anos Circumferential proximal femoral allografts in revision surgery on total hip arthroplasty: case reports with a minimum follow-up of 20 years

    Directory of Open Access Journals (Sweden)

    Bruno Dutra Roos

    2012-01-01

    Full Text Available Dentre as opções para reconstrução femoral em cirurgias de revisão de artroplastia total do quadril (RATQ em defeitos circunferenciais extensos está a utilização de aloenxerto de fêmur proximal. O seu uso permite a correção do mecanismo abdutor do quadril e da discrepância de comprimento dos membros inferiores, além de apresentar potencial osteocondutivo. Os autores relatam os achados clínicos e radiográficos de dois casos de RATQ com uso desta técnica, em seguimento mínimo de 20 anos.Among the options for femoral reconstruction in total hip arthroplasty (THA revision procedures, in cases of extensive circumferential defects, is the use of proximal femoral allografts. This technique makes it possible to correct the hip abductor mechanism and the leg length discrepancy, as well as presenting osteoconductive potential. The authors report the clinical and radiographic results from two cases of THA revision using this technique, with a minimum follow-up of 20 years.

  19. Femur length and biparietal diameter

    African Journals Online (AJOL)

    2014-12-02

    Dec 2, 2014 ... Conclusion: The fetal parameters used in this study were consistently smaller than reported values from European studies up to the 34th week of ... parameters include crown‑rump length, abdominal circumference, femur ... the continuous mid‑line echo is broken by the cavum septi pellucidi, and taken from ...

  20. femur in foetal age determination

    African Journals Online (AJOL)

    Summary. Our objective was to verify ultrasonic measurement of biparietal diameter and femur in foetal age determination in the second and third trimester of pregnancy. The prospec- tive cross sectional study was carried out at the ultrasound department of Aberdeen Maternity Hospital Scotland. The study population ...

  1. A process evaluation of the WHiTE Two trial comparing total hip artroplasty with and without dual mobility component in the treatment of displaced intracapsular fractures of the proximal femur: Can a trial investigating total hip arthroplasty for hip fracture be delivered in the NHS?

    Science.gov (United States)

    Huxley, C; Achten, J; Costa, M L; Griffiths, F; Griffin, X L

    2016-10-01

    The annual incidence of hip fracture is 620 000 in the European Union. The cost of this clinical problem has been estimated at 1.75 million disability-adjusted life years lost, equating to 1.4% of the total healthcare burden in established market economies. Recent guidance from The National Institute for Health and Clinical Excellence (NICE) states that research into the clinical and cost effectiveness of total hip arthroplasty (THA) as a treatment for hip fracture is a priority. We asked the question: can a trial investigating THA for hip fracture currently be delivered in the NHS? We performed a contemporaneous process evaluation that provides a context for the interpretation of the findings of WHiTE Two - a randomised study of THA for hip fracture. We developed a mixed methods approach to situate the trial centre within the context of wider United Kingdom clinical practice. We focused on fidelity, implementation, acceptability and feasibility of both the trial processes and interventions to stakeholder groups, such as healthcare providers and patients. We have shown that patients are willing to participate in this type of research and that surgeons value being part of a team that has a strong research ethos. However, surgical practice does not currently reflect NICE guidance. Current models of service delivery for hip fractures are unlikely to be able to provide timely total hip arthroplasty for suitable patients. Further observational research should be conducted to define the population of interest before future interventional studies are performed.Cite this article: C. Huxley, J. Achten, M. L. Costa, F. Griffiths, X. L. Griffin. A process evaluation of the WHiTE Two trial comparing total hip artroplasty with and without dual mobility component in the treatment of displaced intracapsular fractures of the proximal femur: Can a trial investigating total hip arthroplasty for hip fracture be delivered in the NHS? Bone Joint Res 2016;5:444-452. DOI: 10

  2. Proximal femoral bone geometry in osteoporotic hip fractures in Thailand.

    Science.gov (United States)

    2015-01-01

    A number of different bone geometries have been reported to be correlated with osteoporosis, bone mineral density and fractures. Those correlations are used for diagnosis, treatment and prediction of fracture risk in osteoporosis cases. However there have been no studies of significant bone parameters predicting osteoporosis and hip fracture in Thailand To evaluate the correlation between geometric parameters of the proximal femur and both the Singh index and bone mineral density as well as to investigate the relationship between those two metrics and osteoporotic hip fracture in the Thai population. Forty-four Thai patients with osteoporotic hip fractures andforty-five healthy Thai people matched for age and gender were included in the present study. Bone mineral density and bone geometry from plain hip radiographs of non-fracture sites in the fracture group and proximal femur radiographs of the same site in the healthy group were measured That data were analyzed to determine levels of correlation. Bone geometries were also analyzed to determine hip fracture predictive capacity. Correlation between the Singh index and bone mineral density was significant (p hip fracture (p = 0.014 and p = 0.035, respectively). Each 1 mm reduction in the width of the femoral medial neck cortex increased the osteoporotic hip fracture risk by a factor of 2.7 (OR = 0.37, 95% CI = 0.15-0.93). In the Thai population, bone geometry from plain radiographs can help predict the risk of osteoporotic hip fracture. Osteoporosis is correlated with a low Singh index value. The width of the femoral medial neck cortex is a reliable predictor of hip fracture risk.

  3. Geometric analysis

    CERN Document Server

    Bray, Hubert L; Mazzeo, Rafe; Sesum, Natasa

    2015-01-01

    This volume includes expanded versions of the lectures delivered in the Graduate Minicourse portion of the 2013 Park City Mathematics Institute session on Geometric Analysis. The papers give excellent high-level introductions, suitable for graduate students wishing to enter the field and experienced researchers alike, to a range of the most important areas of geometric analysis. These include: the general issue of geometric evolution, with more detailed lectures on Ricci flow and Kähler-Ricci flow, new progress on the analytic aspects of the Willmore equation as well as an introduction to the recent proof of the Willmore conjecture and new directions in min-max theory for geometric variational problems, the current state of the art regarding minimal surfaces in R^3, the role of critical metrics in Riemannian geometry, and the modern perspective on the study of eigenfunctions and eigenvalues for Laplace-Beltrami operators.

  4. Der umgedrehte Plattenfixateur zur osteosynthetischen Stabilisierung bei erschwerter Frakturheilung am proximalen Femur

    DEFF Research Database (Denmark)

    Mehlhorn, A T; Strohm, P C; Müller, C A

    2009-01-01

    AIM: The aim of the study was to evaluate the application of a locked internal fixator in complex fractures of the proximal femur, in which the internal fixation with standard implants was not possible due to poor quality of bone or already failed internal fixation in the past. METHOD: Ten patien...

  5. Subtrochanteric and diaphyseal femur fractures in patients treated with alendronate: a register-based national cohort study

    DEFF Research Database (Denmark)

    Abrahamsen, Bo; Eiken, Pia; Eastell, Richard

    2009-01-01

    of bone turnover. Two national observational register-based studies were performed: (1) cross-sectional study (N = 11,944) comparing age distribution, exposure, and trauma mechanisms between different types of proximal femur fractures and (2) matched cohort study in patients with prior nonhip fractures (N......Alendronate (aln) is a potent bisphosphonate with a prolonged duration of action. Recent reports have found long-term aln use to be common in patients with subtrochanteric or proximal diaphyseal femur fracture, raising concerns that these fractures could be a consequence of excessive suppression...... = 5187 + 10,374), testing the hypothesis that the increase in the risk of subsequent atypical femur fractures exceeded the increase in typical hip fractures. We also sought evidence of a dose-response relationship, where high adherence to or long-term use of aln led to more atypical femur fractures. We...

  6. A case of acute bilateral femur fracture with vascular injury

    Directory of Open Access Journals (Sweden)

    Slavisa Zagorac

    2016-01-01

    Full Text Available The femoral fractures remain the great challenge for orthopedic surgeons regarding time of fixation and appropriate fixation techniques. There is a bimodal distribution of fractures occurring most frequently in young males after high-energy trauma (motor vehicle accidents and in elderly females after falls from standing. Young patients with femoral fracture are under the great risk of multiple injuries. Hence, the great significance is optimal time of fixation. We present a case of unusual pattern of injury and fixation technique of bilateral proximal femur fracture associated with vascular injury, with very satisfied outcome.

  7. Geometric mechanics

    CERN Document Server

    Muniz Oliva, Waldyr

    2002-01-01

    Geometric Mechanics here means mechanics on a pseudo-riemannian manifold and the main goal is the study of some mechanical models and concepts, with emphasis on the intrinsic and geometric aspects arising in classical problems. The first seven chapters are written in the spirit of Newtonian Mechanics while the last two ones as well as two of the four appendices describe the foundations and some aspects of Special and General Relativity. All the material has a coordinate free presentation but, for the sake of motivation, many examples and exercises are included in order to exhibit the desirable flavor of physical applications.

  8. In vitro ultrasound measurement at the human femur.

    Science.gov (United States)

    Padilla, F; Akrout, L; Kolta, S; Latremouille, C; Roux, C; Laugier, P

    2004-11-01

    Measurements of broadband ultrasonic attenuation (BUA) represent an established means of skeletal status assessment in osteoporosis. Today, the skeletal site that is the most widely used clinically is the calcaneus (heel bone). However, we hypothesized that fracture risk predictions could be improved if ultrasound measurements were performed directly at the main site of fracture, e.g., the proximal femur. The goal of this paper is to demonstrate in vitro the feasibility of quantitative ultra sound (QUS) imaging at the upper part of fee femur, and to investigate the relationships of BUA to bone mineral density (BMD). Forty-four excise human femurs were measured in transmission with a pair of focused 0.5-MHz central frequency transducers. Two-dimensional scans were performed, and the radio frequency (rf) signals were recorded at each measurement point. A data acceptance criterion for region of interest (ROI) selection was established based on the linearity of the frequency-dependent attenuation. Five measurements with repositioning were performed on each sample to determine the reproducibility. Dual energy x-ray absorptiometry (DXA) scans have been performed on the samples for BMD measurements: Three ROIs were selected in the specimens: greater, trochanter intertrochanteric, and femoral neck regions. Coefficient of variations were in the range 1.6% to 2.5%. The determination coefficients (r(2)) between BUA and BMD in site-matched ROIs were 0.81, 0.78, and 0.73, respectively, for the greater trochanteric, intertrochanteric, and femoral neck regions. Our results are consistent with data previously shown at the calcaneus and demonstrate the feasibility of QUS measurements at the femur in vitro, with reasonable reproducibility.

  9. Proximal femoral geometry before and after varus rotational osteotomy in children with cerebral palsy and neuromuscular hip dysplasia.

    Science.gov (United States)

    Davids, Jon R; Gibson, Thomas W; Pugh, Linda I; Hardin, James W

    2013-03-01

    Surgical management of hip dysplasia in children with cerebral palsy (CP) usually includes varus rotational osteotomy (VRO) of the proximal femur. Several techniques of VRO (end-to-end, EE; end-to-side, ES) have been designed to maximize correction and minimize associated deformities. The goals of the current study were to establish the prevalence and contribution of caput valgum to coxa valga deformity in children with CP, compare the geometry of the proximal femur after EE and ES techniques of VRO, and document the response of the proximal femur to subsequent growth after VRO. The records of 75 children with CP (Gross Motor Function Classification System, levels IV and V) with 137 surgically treated hips were retrospectively reviewed. Outcomes were limited to the technical domain (eg, radiographic measurements and surgical complications). Measurements made for each hip (preoperative, operative, and follow-up) included the neck-shaft angle (NSA), head-shaft angle (HSA), and the medialization index. The mean age at the time of surgery was 7 years. The mean follow-up was 5 years and 6 months. Caput valgum was present in all hips, increasing the actual geometric valgus by a mean of 10%. The ES technique was more effective at medializing the femoral shaft; however, this benefit was lost with growth (P = 0.891). The ES technique was more effective at achieving and maintaining correction of the NSA (P = 0.026). Maintenance of correction of the HSA was comparable for both ES and EE surgical techniques (P = 0.099). Subsequent growth of the proximal femur resulted in loss of correction of the NSA (mean 29%) and HSA (mean 21%). Caput valgum is usually present in children with CP who are undergoing surgical hip reconstruction. The ES technique is a reasonable alternative for the correction of neuromuscular hip dysplasia associated with extreme coxa valga and long femoral necks. Recurrence of coronal plane deformity with growth after VRO is common, and further study is

  10. Geometric horizons

    Science.gov (United States)

    Coley, Alan A.; McNutt, David D.; Shoom, Andrey A.

    2017-08-01

    We discuss black hole spacetimes with a geometrically defined quasi-local horizon on which the curvature tensor is algebraically special relative to the alignment classification. Based on many examples and analytical results, we conjecture that a spacetime horizon is always more algebraically special (in all of the orders of specialization) than other regions of spacetime. Using recent results in invariant theory, such geometric black hole horizons can be identified by the alignment type II or D discriminant conditions in terms of scalar curvature invariants, which are not dependent on spacetime foliations. The above conjecture is, in fact, a suite of conjectures (isolated vs dynamical horizon; four vs higher dimensions; zeroth order invariants vs higher order differential invariants). However, we are particularly interested in applications in four dimensions and especially the location of a black hole in numerical computations.

  11. Proximal Hypospadias

    Science.gov (United States)

    Kraft, Kate H.; Shukla, Aseem R.; Canning, Douglas A.

    2011-01-01

    Hypospadias results from abnormal development of the penis that leaves the urethral meatus proximal to its normal glanular position. Meatal position may be located anywhere along the penile shaft, but more severe forms of hypospadias may have a urethral meatus located at the scrotum or perineum. The spectrum of abnormalities may also include ventral curvature of the penis, a dorsally redundant prepuce, and atrophic corpus spongiosum. Due to the severity of these abnormalities, proximal hypospadias often requires more extensive reconstruction in order to achieve an anatomically and functionally successful result. We review the spectrum of proximal hypospadias etiology, presentation, correction, and possible associated complications. PMID:21516286

  12. Increased intrinsic stiffness and mineralization in femurs of adult rats after high intensity treadmill running training.

    Science.gov (United States)

    Bozzini, Clarisa; Viscor, Ginés; Kristjánsson, Juan C Ríos; Picasso, Emilio; Champin, Graciela; Alippi, Rosa M; Bozzini, Carlos E

    2017-01-01

    Physical activity plays a tremendous role in determining bone mechanical behavior, which is superimposed to gravidity. Compare the geometric and material responses of the rat femur to a high intensity treadmill running training of a relatively short duration, as assessed by 3-point mechanical test. Mature male rats (180.0 ± 30 g) were assigned (7 rats/group) to no exercise (NE) or treadmill exercise (EX). After a preconditioning period, the running speed was set at 45 cm.seg-1 during 2 wks, frequency 5 d/wk, 2-hour sessions/day. Body weight and weight of the crural quadriceps were registered at euthanasia. The right femur was mechanically tested through 3-point bending. The left femur was ashed to estimate bone mineral content. Geometric and material bone properties were estimated directly or calculated by appropriate equations. 1) Final body weight was 14% reduced in EX rats, while the crural quadriceps was 47% increased. Yield and fracture loads, and structural stiffness were significantly higher in the EX rats, as were the apparent elastic modulus, the bone mineral content and the degree of mineralization. Geometric properties were not affected. High intensity treadmill running training increases bone strength and stiffness by increasing material stiffness and mineralization, without affecting geometric bone parameters.

  13. The effect of implant overlap on the mechanical properties of the femur.

    Science.gov (United States)

    Harris, Timothy; Ruth, John T; Szivek, John; Haywood, Brett

    2003-05-01

    The most biomechanically stable relationship between the side plate of a compression hip screw (CHS) and retrograde intramedullary (IM) femoral nail has not been described in the literature. This becomes a clinical issue when treating supracondylar femur fractures with a retrograde nail in patients with a history of compression hip screw fixation of intertrochanteric fractures. The proximal end of the nail and the interlocking screws may act as a stress riser in the femoral diaphysis. The purpose of this study is to determine the biomechanical consequences of the amount of implant overlap between a CHS plate and retrograde IM femoral nail. Nine paired fresh-frozen cadaver femora from elderly donors were cleaned of soft tissue and fixed with uniaxial strain gauges. Each femur was loaded three times in a fall-loading configuration to 50 kg at a rate of 1 Hz. The study consisted of two phases. In phase 1, six pair were randomly divided into a control and test femur from each pair. Three states were compared on each test femur: uninstrumented, instrumented with CHS, and instrumented with CHS and retrograde nail. The control femur consisted of the matched femur tested in two states: uninstrumented and instrumented with a CHS. The femora were then loaded to failure. The tests were performed with the retrograde nail and CHS gapped 3 cm, kissing, and overlapping by two screw holes (two pair for each state). In phase 2, each of the remaining three pair were instrumented with a CHS and retrograde nail overlapping in one femur and gapped in the matched femur and tested in the same manner. Data analysis was performed using Pearson's correlation coefficients between groups. Paired samples t tests were used to compare differences within test states and independent samples t tests were used to compare differences between femora. Mean strain at 50-kg load, load-versus-strain patterns, failure patterns, and load and strain at failure were recorded. RESULTS; Correlation coefficients

  14. Association between femur size and a focal defect of the superior femoral neck.

    Science.gov (United States)

    Gee, A H; Treece, G M; Tonkin, C J; Black, D M; Poole, K E S

    2015-12-01

    Within each sex, there is an association between hip fracture risk and the size of the proximal femur, with larger femurs apparently more susceptible to fracture. Here, we investigate whether the thickness and density of the femoral cortex play a role in this association: might larger femurs harbour focal, cortical defects? To answer this question, we used cortical bone mapping to measure the distribution of cortical mass surface density (CMSD, mg/cm(2)) in cohorts of 308 males and 125 females. Principal component analysis of the various femoral surfaces led to a measure of size that is linearly independent from shape. After mapping the data onto a canonical femur surface, we used statistical parametric mapping to identify any regions where CMSD depends on size, allowing for other confounding covariates including shape. Our principal finding was a focal patch on the superior femoral neck, where CMSD is reduced by around 1% for each 1% increase in proximal-distal size (pfracture risk. Copyright © 2015. Published by Elsevier Inc.

  15. Load along the femur shaft during activities of daily living.

    Science.gov (United States)

    D'Angeli, V; Belvedere, C; Ortolani, M; Giannini, S; Leardini, A

    2013-08-09

    A comprehensive knowledge of the loads applied during activities of daily living to the femur shaft is necessary to the design of direct attachments of relevant prostheses. A motion analysis system was used together with an established protocol with skin markers to estimate the three components of the forces and moments acting on ten equidistant points along the full femur shaft. Twenty healthy young volunteers were analyzed while performing three repetitions of the following tasks: level walking at three different speeds, straight-line and with sudden changes of direction to the right and to the left, stairs ascending and descending, squat, rising from a chair and sitting down. Average load patterns, after normalisation for body weight and height, were calculated over subjects for each point, about the three anatomical axes, and for each motor task. These patterns were found consistent over subjects, but different among the anatomical axes and tasks. In general, the moments were observed limitedly influenced by the progression speed, and higher for more proximal points. The moments were also higher in abd/adduction (8.1% body weight*height on average), nearly three times larger than those in flex/extension (2.6) during stair descending. The largest value over all moments was 164.8 N m, abd/adduction in level walking at high speed. The present results should be of value also for a most suitable level for amputation in transfemoral amputation, for in-vitro mechanical tests and for finite element models of the femur. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Pindborg tumor in the distal femur

    OpenAIRE

    Sussela, Alex Oliboni; Alves, Paulo Ricardo Picon; Silva, Vinicius Duval da; Bolze, Carlos Daniel de Garcia; Serafini, Osvaldo André

    2017-01-01

    ABSTRACT To describe a case of possible diagnosis of Pindborg tumor on the distal femur. A 32-years-old female patient, a native of Bolivia, resident in Brazil, arrived to this service for tumor research in the right femur. After biopsies and resection of the lesion, the case was referred to analysis and consultancy in the United States. In a report of review by the Pathology Laboratory, it was characterized the histological appearance and immunohistochemical profile were characteristic of Pi...

  17. Metachronous bilateral subtrochanteric fracture of femur in an osteopetrotic bone: A case report with technical note☆

    Science.gov (United States)

    Kumar, Dharmendra; Jain, Vijay Kumar; lal, Hitesh; Arya, Rajinder Kumar; Sinha, Skand

    2012-01-01

    Osteopetrosis is a rare inherited skeletal disorder characterized by increased density. The increased fragility of such dense bone results in a greater incidence of fractures, especially around hip and proximal femur. The surgical treatment of such fractures is difficult due to hard but brittle structure of bone. Herein we report a case of bilateral subtrochanteric fracture in an osteopetrotic patient. It was fixed using a dynamic hip screw with plate. PMID:26403447

  18. Unilateral proximal focal femoral deficiency, fibular aplasia, tibial ...

    African Journals Online (AJOL)

    ... dominant mutation with possible gonadal mosaicism and with variable expression in the family, as limb anomaly in one child and cyanotic congenital heart disease in another child. Keywords: Short femur; Limb anomaly; FFU syndrome; Proximal focal femoral deficiency; Fibular aplasia; Tibial campomelia; Oligosyndactyly ...

  19. Long‑Term Outcome of Endoprosthetic Replacement for Proximal ...

    African Journals Online (AJOL)

    Giant cell tumor (GCT) represents 5% of neoplasms of bone. It is a benign locally aggressive tumor usually involving the distal end of the femur, proximal tibia and distal radius in young adults.[1-3] The main variables to be considered for planning treatment include the site of involvement and Campanacci stage of the tumor.

  20. Femur ultrasound (FemUS)--first clinical results on hip fracture discrimination and estimation of femoral BMD.

    Science.gov (United States)

    Barkmann, R; Dencks, S; Laugier, P; Padilla, F; Brixen, K; Ryg, J; Seekamp, A; Mahlke, L; Bremer, A; Heller, M; Glüer, C C

    2010-06-01

    A quantitative ultrasound (QUS) device for measurements at the proximal femur was developed and tested in vivo (Femur Ultrasound Scanner, FemUS). Hip fracture discrimination was as good as for DXA, and a high correlation with hip BMD was achieved. Our results show promise for enhanced QUS-based assessment of osteoporosis. Dual X-ray absorptiometry (DXA) at the femur is the best predictor of hip fractures, better than DXA measurements at other sites. Calcaneal quantitative ultrasound (QUS) can be used to estimate the general osteoporotic fracture risk, but no femoral QUS measurement has been introduced yet. We developed a QUS scanner for measurements at the femur (Femur Ultrasound Scanner, FemUS) and tested its in vivo performance. Using the FemUS device, we obtained femoral QUS and DXA on 32 women with recent hip fractures and 30 controls. Fracture discrimination and the correlation with femur bone mineral density (BMD) were assessed. Hip fracture discrimination using the FemUS device was at least as good as with hip DXA and calcaneal QUS. Significant correlations with total hip bone mineral density were found with a correlation coefficient R (2) up to 0.72 and a residual error of about one half of a T-score in BMD. QUS measurements at the proximal femur are feasible and show a good performance for hip fracture discrimination. Given the promising results, this laboratory prototype should be reengineered to a clinical applicable instrument. Our results show promise for further enhancement of QUS-based assessment of osteoporosis.

  1. Femur-mounted navigation system for the arthroscopic treatment of femoroacetabular impingement

    Science.gov (United States)

    Park, S. H.; Hwang, D. S.; Yoon, Y. S.

    2013-07-01

    Femoroacetabular impingement stems from an abnormal shape of the acetabulum and proximal femur. It is treated by resection of damaged soft tissue and by the shaping of bone to resemble normal features. The arthroscopic treatment of femoroacetabular impingement has many advantages, including minimal incisions, rapid recovery, and less pain. However, in some cases, revision is needed owing to the insufficient resection of damaged bone from a misreading of the surgical site. The limited view of arthroscopy is the major reason for the complications. In this research, a navigation method for the arthroscopic treatment of femoroacetabular impingement is developed. The proposed navigation system consists of femur attachable measurement device and user interface. The bone mounted measurement devices measure points on head-neck junction for registration and position of surgical instrument. User interface shows the three-dimensional model of patient's femur and surgical instrument position that is tracked by measurement device. Surgeon can know the three-dimensional anatomical structure of hip joint and surgical instrument position on surgical site using navigation system. Surface registration was used to obtain relation between patient's coordinate at the surgical site and coordinate of three-dimensional model of femur. In this research, we evaluated the proposed navigation system using plastic model bone. It is expected that the surgical tool tracking position accuracy will be less than 1 mm.

  2. Thrust plate prosthesis for proximal femoral deformity: a series of 15 patients

    OpenAIRE

    Karatosun, Vasfi; Ünver, Bayram; Gultekin, Alper; Gunal, Izge

    2011-01-01

    Objectives: Patients with coxarthrosis and proximal femoral deformity experience problems with total hip arthroplasty. A custom-made prosthesis or a proximal osteotomy is required for such cases, and these also increase the rate of complications. The purpose of this study was to evaluate the results of the thrust plate prosthesis (TPP) in patients with deformity of the proximal femur. Methods: Fifteen patients (7 females, 8 males) with a mean age of 56.4 years (range 19-75 years) at the...

  3. GUNSHOT FRACTURES OF TIBIA AND FEMUR - EXCELLENT ...

    African Journals Online (AJOL)

    2011-10-10

    Oct 10, 2011 ... GUNSHOT FRACTURES OF TIBIA AND FEMUR - EXCELLENT RESULTS WITH REAMED BONE MARROW GRAFT. AND INTERLOCKING .... between injury and surgery as well as associated injuries were documented. ..... injection in the treatment. of delayed and non-union in long bones. Singapore Med ...

  4. X-Ray Exam: Femur (Upper Leg)

    Science.gov (United States)

    ... leg, and an image is recorded on special film or a computer. This image shows the soft tissues and the bone in the upper leg, which is called the femur. The X-ray image is black and white. Dense body parts that block the passage of the X- ...

  5. Retrograde Intramedullary Nailing for Distal Femur Fracture with Osteoporosis

    OpenAIRE

    Kim, Jihyeung; Kang, Seung-baik; Nam, Kyungpyo; Rhee, Seung Hwan; Won, Jong Won; Han, Hyuk-Soo

    2012-01-01

    Background The incidence of distal femur fracture in the elderly has been increasing recently, and commonly occurs with osteoporosis. Retrograde intramedullary nailing has been considered a good surgical option for distal femur fracture. The purpose of the present study was to present our surgical results with retrograde intramedullary nailing for distal femur fractures with osteoporosis. Methods Thirteen patients diagnosed with extra-articular distal femur fracture and osteoporosis and manag...

  6. Quantitative ultrasound of cortical bone in the femoral neck predicts femur strength: results of a pilot study.

    Science.gov (United States)

    Grimal, Quentin; Grondin, Julien; Guérard, Sandra; Barkmann, Reinhard; Engelke, Klaus; Glüer, Claus-C; Laugier, Pascal

    2013-02-01

    A significant risk of femoral neck (FN) fracture exists for men and women with an areal bone mineral density (aBMD) higher than the osteoporotic range, as measured with dual-energy X-ray absorptiometry (DXA). Separately measuring the cortical and trabecular FN compartments and combining the results would likely be a critical aspect of enhancing the diagnostic capabilities of a new technique. Because the cortical shell determines a large part of FN strength a novel quantitative ultrasound (QUS) technique that probes the FN cortical compartment was implemented. The sensitivity of the method to variations of FN cortical properties and FN strength was tested. Nine femurs (women, mean age 83 years) were subjected to QUS to measure the through transmission time-of-flight (TOF) at the FN and mechanical tests to assess strength. Quantitative computed tomography (QCT) scans were performed to enable analysis of the dependence of TOF on bone parameters. DXA was also performed for reference. An ultrasound wave propagating circumferentially in the cortical shell was measured in all specimens. Its TOF was not influenced by the properties of the trabecular compartment. Averaged TOF for nine FN measurement positions/orientations was significantly correlated to strength (R2  = 0.79) and FN cortical QCT variables: total BMD (R(2)  = 0.54); regional BMD in the inferoanterior (R2  = 0.90) and superoanterior (R2  = 0.57) quadrants; and moment of inertia (R2  = 0.71). The results of this study demonstrate that QUS can perform a targeted measurement of the FN cortical compartment. Because the method involves mechanical guided waves, the QUS variable is related to the geometric and material properties of the cortical shell (cortical thickness, tissue elasticity, and porosity). This work opens the way to a multimodal QUS assessment of the proximal femur, combining our approach targeting the cortical shell with the existing modality sensitive to the trabecular

  7. Usefullness of three-dimensional templating software to quantify the contact state between implant and femur in total hip arthroplasty.

    Science.gov (United States)

    Inoue, Daisuke; Kabata, Tamon; Maeda, Toru; Kajino, Yoshitomo; Fujita, Kenji; Hasegawa, Kazuhiro; Yamamoto, Takashi; Takagi, Tomoharu; Ohmori, Takaaki; Tsuchiya, Hiroyuki

    2015-12-01

    It would be ideal if surgeons could precisely confirm whether the planned femoral component achieves the best fit and fill of implant and femur. However, the cortico-cancellous interfaces can be difficult to standardize using plain radiography, and therefore, determining the contact state is a subjective decision by the examiner. Few reports have described the use of CT-based three-dimensional templating software to quantify the contact state of stem and femur in detail. The purpose of this study was to use three-dimensional templating software to quantify the implant-femur contact state and develop a technique to analyze the initial fixation pattern of a cementless femoral stem. We conducted a retrospective review of 55 hips in 53 patients using a short proximal fit-and-fill anatomical stem (APS Natural-Hip™ System). All femurs were examined by density mapping which can visualize and digitize the contact state. We evaluated the contact state of implant and femur by using density mapping. The varus group (cases that had changed varus 2° by 3 months after surgery) consisted of 11 hips. The varus group showed no significant difference with regard to cortical contact in the proximal medial portion (Gruen 7), but the contact area in the distal portion (Gruen 3 and Gruen 5) was significantly lower than that of non-varus group. Density mapping showed that the stem only has to be press-fit to the medial calcar, but also must fill the distal portion of the implant in order to achieve the ideal contact state. Our results indicated that quantifying the contact state of implant and femur by using density mapping is a useful technique to accurately analyze the fixation pattern of a cementless femoral stem.

  8. Weakness in the mechanical properties of the femurs of growing female rats exposed to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Brzoska, Malgorzata M.; Moniuszko-Jakoniuk, Janina [Medical University of Bialystok, Department of Toxicology, Bialystok (Poland); Majewska, Katarzyna [University of Warmia and Mazury (Poland). Faculty of Food Science

    2005-09-01

    The study assessed the effect of cadmium (Cd) intoxication on the risk of deformities and fractures of the growing bones of female rats, in order to model human exposure to this metal. For this purpose, bone mineral density and mechanical properties of the proximal and distal ends and diaphysis of the femur were investigated in female Wistar rats exposed to 1, 5 and 50 mg Cd/l in drinking water for 3, 6, 9 and 12 months after the onset of weaning. Daily Cd doses received from drinking water during the treatment period were in the following ranges: 0.059-0.219, 0.236-1.005 and 2.247-9.649 mg/kg body weight at 1, 5 and 50 mg Cd/l, respectively. Biomechanical properties of the femoral proximal and distal ends were evaluated in a compression test, and those of the femoral diaphysis in a cutting test, with loading perpendicular to the longitudinal axis of the bone in all tests. The mineralization and mechanical properties of the bone tissue at various locations on the femur were affected by exposure to Cd in a dose- and duration-dependent manner. Exposure to 1 mg Cd/l (corresponding to low human exposure) during skeletal development weakened the fracture strength of the femoral neck and the trabecular bone at the level of the distal end of the femur and affected the elastic properties of the cortical bone at the femoral diaphysis. At higher levels of Cd exposure, adverse effects were generally observed after a shorter exposure period than for 1 mg Cd/l, and were more advanced. The cadmium-induced weakening of the biomechanical properties of bone at particular sites on the femur correlated with the decreased bone mineralization. The results indicate that even a low exposure to Cd may affect the mineralization and biomechanical properties of growing bone, thus enhancing the risk of fracture. (orig.)

  9. Weakness in the mechanical properties of the femur of growing female rats exposed to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Brzoska, Malgorzata M.; Moniuszko-Jakoniuk, Janina [Medical University of Bialystok, Department of Toxicology, Bialystok (Poland); Majewska, Katarzyna [University of Warmia and Mazury, Olsztyn (Poland). Faculty of Food Science

    2005-05-01

    This study was aimed at assessing the effect of cadmium (Cd) intoxication on the risk of deformities and fractures of the growing bone on a female rat model of human exposure to this metal. For this purpose, bone mineral density (BMD) and mechanical properties of the proximal and distal ends and diaphysis of the femur were investigated in female Wistar rats exposed to 1, 5, and 50 mg Cd L{sup -1} in drinking water for 3, 6, 9, and 12 months since weaning. Daily Cd doses received from the drinking water during the treatment period were in the ranges 0.059-0.219, 0.236-1.005, and 2.247-9.649 mg kg{sup -1} body weight at 1, 5, and 50 mg Cd L{sup -1}, respectively. Biomechanical properties of the femoral proximal and distal ends were evaluated in a compression test and those of the femoral diaphysis in a cutting test with loading perpendicular to the bone longitudinal axis in all tests. Cd dose- and exposure duration-dependently affected the mineralization and mechanical properties of the bone tissue at various locations of the femur. Exposure to 1 mg Cd L{sup -1} (corresponding to low human exposure) during skeletal development weakened the fracture strength of the femoral neck and of the trabecular bone at the level of the distal end of the femur and affected the elastic properties of the cortical bone at the femoral diaphysis. At the higher levels of Cd treatment, the adverse action generally occurred after shorter exposure than at 1 mg Cd L{sup -1} and was more seriously advanced. The Cd-induced weakening in the bone biomechanical properties at particular sites of the femur correlated with the decreased bone mineralization. The results indicate that even low exposure to Cd may affect the mineralization and biomechanical properties of growing bone, thus increasing the risk of fractures. (orig.)

  10. A Validated Open-Source Multisolver Fourth-Generation Composite Femur Model.

    Science.gov (United States)

    MacLeod, Alisdair R; Rose, Hannah; Gill, Harinderjit S

    2016-12-01

    Synthetic biomechanical test specimens are frequently used for preclinical evaluation of implant performance, often in combination with numerical modeling, such as finite-element (FE) analysis. Commercial and freely available FE packages are widely used with three FE packages in particular gaining popularity: abaqus (Dassault Systèmes, Johnston, RI), ansys (ANSYS, Inc., Canonsburg, PA), and febio (University of Utah, Salt Lake City, UT). To the best of our knowledge, no study has yet made a comparison of these three commonly used solvers. Additionally, despite the femur being the most extensively studied bone in the body, no freely available validated model exists. The primary aim of the study was primarily to conduct a comparison of mesh convergence and strain prediction between the three solvers (abaqus, ansys, and febio) and to provide validated open-source models of a fourth-generation composite femur for use with all the three FE packages. Second, we evaluated the geometric variability around the femoral neck region of the composite femurs. Experimental testing was conducted using fourth-generation Sawbones® composite femurs instrumented with strain gauges at four locations. A generic FE model and four specimen-specific FE models were created from CT scans. The study found that the three solvers produced excellent agreement, with strain predictions being within an average of 3.0% for all the solvers (r2 > 0.99) and 1.4% for the two commercial codes. The average of the root mean squared error against the experimental results was 134.5% (r2 = 0.29) for the generic model and 13.8% (r2 = 0.96) for the specimen-specific models. It was found that composite femurs had variations in cortical thickness around the neck of the femur of up to 48.4%. For the first time, an experimentally validated, finite-element model of the femur is presented for use in three solvers. This model is freely available online along with all the supporting validation data.

  11. Cadaveric analysis of capsular attachments of the distal femur related to pin and wire placement.

    Science.gov (United States)

    Lowery, Kathryn; Dearden, Paul; Sherman, Kevin; Mahadevan, Vishy; Sharma, Hemant

    2015-01-01

    Septic arthritis following intra-capsular penetration of the knee by external fixation devices is a complication of traction/fixation devices inserted in the lower extremity [1,2]. The authors were unable to find reference to or exact measurements of the capsular attachments relating to the distal femur documented in the current literature. This study aimed to demonstrate the capsular attachments and reflections of the distal femur to determine safe placements of wires or traction devices. The attachments of the capsule to the distal femur were measured in 10 unembalmed cadaveric knees. Capsular attachments were measured anteriorly at the maximal extension of the supra-patella pouch. Medially and laterally measurements were expressed as percentages related to the maximal AP diameter of the distal femur. Mean distance from the centre of the anterior part of the notch to the superior fold was 79.5mm (Range 48.1-120.7 mm). The medial capsular reflections measured in a plane from the adductor tubercle to the anterior edge of the medial femoral condyle demonstrated the capsular reflection was attached an average of 57% back from the anterior edge (Range 41-74%). Laterally the capsular reflections on a line drawn from the maximal diameter in the sagittal plane were attached an average of 48% from the anterior reference point (Range 33-57%). Measuring the reflections at 45 degrees to the long axis of the femur in the sagittal plane the attachment was an average of 51% from the anterior reference point. Capsular reflections varied among specimens. Medially the capsule attachment was up to 74% of diameter of distal femur at the level of the adductor tubercle. Therefore, the insertion of distal femoral traction pins or similar should be placed proximal to the adductor tubercle and no further than 25% of the distance to the anterior cortex. Care is also needed to ensure pins do not travel to exit too anteriorly on the lateral side as capsular attachments were found to be up

  12. Periosteal osteoid osteoma of the distal femur

    Directory of Open Access Journals (Sweden)

    Mohammed Fahd Amar

    2010-07-01

    Full Text Available Periosteal osteoid osteoma is extremely rare. The diagnosis is not always clear. We report a case of periosteal osteoid osteoma arising from the posterior surface of the right distal femur in a 21-year-old woman. After careful evaluation and excisional biopsy, histological examination confirmed the diagnosis of osteoid osteoma, showing the nidus, surrounding osteosclerosis, and catarrhal synovitis. The lesion was treated successfully with excision of the nidus.

  13. Comparison of morphological features in the femur between femoral neck fractures and femoral intertrochanteric fractures.

    Science.gov (United States)

    Yamauchi, Koun; Naofumi, Mitsuishi; Sumida, Hisashi; Fukuta, Shoji; Hori, Hirohiko

    2016-09-01

    The purpose of this study is to make proximal femur fracture types more predictable by considering morphological features of an acetabulum as well as of a proximal femur in the Japanese population. A retrospective review of radiographs of the proximal femoral fractures was conducted in patients registered from 2010 to 2012, dividing into patients with femoral neck fractures; Group Neck (n = 101), and patients with femoral intertrochanteric fractures; Group IT (n = 99). Intergroup comparison was conducted: age, sex, height, weight, the ratios of femoral intertrochanteric length (IT Length), femoral neck length (Neck Length), femoral neck width (Neck Width), lateral offset length (Offset) to femoral head diameter, neck-shaft angle (N-S angle), and center-edge angle of the acetabulum (C-E angle), adjusting for age. Multiple logistic regression analysis was conducted among these parameters. The Group IT showed significantly older age than the Group Neck. Greater C-E angle in Group IT was observed in the patients in their 80s and 90s years of age. The Group Neck showed greater N-S angle only in the patients in their 80s years of age. In multiple logistic regression analysis, the impact of the age and the C-E angle on the fracture types was similar (odds ratio 1.08, 1.09, respectively, p fracture types.

  14. Negative Impact of Aromatase Inhibitors on Proximal Femoral Bone Mass and Geometry in Postmenopausal Women with Breast Cancer.

    Science.gov (United States)

    Lee, Su Jin; Kim, Kyoung Min; Brown, J Keenan; Brett, Alan; Roh, Yun Ho; Kang, Dae Ryong; Park, Byeong Woo; Rhee, Yumie

    2015-12-01

    Aromatase inhibitors (AIs), the standard therapy for estrogen receptor- or progesterone receptor-positive breast cancer in postmenopausal women, lead to increased hip fractures in breast cancer patients. To investigate the mechanism of increased incidence of hip fractures in breast cancer patients treated with AIs, we evaluated bone mineral density (BMD) in the cortical and trabecular compartments and assessed femoral geometry using quantitative computed tomography (QCT) in breast cancer patients. In total, 249 early breast cancer patients who underwent QCT in their fifties (mean age 54.3 years) were retrospectively analyzed. Proximal femoral BMD and geometrical parameters were compared. In all regions of the proximal femur, cortical areal BMDs were lower in the AI group than in the non-AI group (p modulus and cross-sectional moment of inertia, were significantly lower in the AI group than in the non-AI group (p breast cancer patients is associated with deterioration of femoral cortical BMD and geometry, which could contribute in site-specific weakened bone strength and increased incidence of hip fractures.

  15. Geometric Design Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The mission of the Geometric Design Laboratory (GDL) is to support the Office of Safety Research and Development in research related to the geometric design...

  16. Proximal renal tubular acidosis

    Science.gov (United States)

    Renal tubular acidosis - proximal; Type II RTA; RTA - proximal; Renal tubular acidosis type II ... by alkaline substances, mainly bicarbonate. Proximal renal tubular acidosis (Type II RTA) occurs when bicarbonate is not ...

  17. On the existence of best proximity points for generalized contractions

    Directory of Open Access Journals (Sweden)

    V. Vetrivel

    2014-04-01

    Full Text Available In this article we establish the existence of a unique best proximity point for some generalized non self contractions on a metric space in a simpler way using a geometric result. Our results generalize some recent best proximity point theorems and several fixed point theorems proved by various authors.

  18. Rotationplasty of the lower limb for congenital defects of the femur.

    Science.gov (United States)

    Torode, I P; Gillespie, R

    1983-11-01

    The operative technique for combined fusion of the knee and rotationplasty of the limb in the management of congenital deficiency of the femur is presented. The technique described allows earlier definitive prosthetic fitting of a child with proximal femoral deficiency; it has reduced the number of operative procedures needed to obtain the optimal function from that deficient limb; and it has enabled these procedures to be performed at an earlier age. The technique differs from those previously described and represents a significant improvement in management of the patient with femoral deficiency.

  19. Transverse Stress Fracture of the Proximal Patella

    Science.gov (United States)

    Atsumi, Satoru; Arai, Yuji; Kato, Ko; Nishimura, Akinobu; Nakazora, Shigeto; Nakagawa, Shuji; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Sudo, Akihiro; Kubo, Toshikazu

    2016-01-01

    Abstract Among stress fractures associated with sports activities, patellar stress fracture is rare. Regarding patella stress fractures, so far only distal transverse or lateral longitudinal fractures have been reported, but there are no reports of transverse fractures occurring in the proximal patella. We describe an extremely rare case of transverse stress fracture of proximal patella in a 9-year-old athlete. A 9-year old boy, who participated in sports (sprints and Kendo) presented with left knee pain without any external injury. In plain radiographs, a fracture line was observed in the proximal 1/3 of the left patella, and a patella stress fracture was diagnosed. For treatment, because 7 months of conservative therapy showed no improvement, internal fixation was carried out using Acutrak screws, and bone union was thus achieved. Three months after the operation, he was able to return to his previous level of athletic sports activity. Regarding the mechanism of onset, it is believed that the causes are longitudinal traction force and patellofemoral contact pressure. On the other hand, the contact region of the patella with the femur changes with the flexion angle of the knee. In the current case, the fracture occurred at a site where the patella was in contact with the femur at a flexion angle of >90°, so it is believed that it occurred as a clinical condition from being subjected to repeated longitudinal traction force and patellofemoral contact pressure at a flexion angle of >90°, during the sports activities of sprints and Kendo. The nonunion of the transverse stress fracture of his proximal patella was successfully treated with internal fixation using Acutrak screws. PMID:26871789

  20. Shape Ontogeny of the Distal Femur in the Hominidae with Implications for the Evolution of Bipedality.

    Directory of Open Access Journals (Sweden)

    Melissa Tallman

    Full Text Available Heterochrony has been invoked to explain differences in the morphology of modern humans as compared to other great apes. The distal femur is one area where heterochrony has been hypothesized to explain morphological differentiation among Plio-Pleistocene hominins. This hypothesis is evaluated here using geometric morphometric data to describe the ontogenetic shape trajectories of extant hominine distal femora and place Plio-Pleistocene hominins within that context. Results of multivariate statistical analyses showed that in both Homo and Gorilla, the shape of the distal femur changes significantly over the course of development, whereas that of Pan changes very little. Development of the distal femur of Homo is characterized by an elongation of the condyles, and a greater degree of enlargement of the medial condyle relative to the lateral condyle, whereas Gorilla are characterized by a greater degree of enlargement of the lateral condyle, relative to the medial. Early Homo and Australopithecus africanus fossils fell on the modern human ontogenetic shape trajectory and were most similar to either adult or adolescent modern humans while specimens of Australopithecus afarensis were more similar to Gorilla/Pan. These results indicate that shape differences among the distal femora of Plio-Pleistocene hominins and humans cannot be accounted for by heterochrony alone; heterochrony could explain a transition from the distal femoral shape of early Homo/A. africanus to modern Homo, but not a transition from A. afarensis to Homo. That change could be the result of genetic or epigenetic factors.

  1. Shape Ontogeny of the Distal Femur in the Hominidae with Implications for the Evolution of Bipedality.

    Science.gov (United States)

    Tallman, Melissa

    2016-01-01

    Heterochrony has been invoked to explain differences in the morphology of modern humans as compared to other great apes. The distal femur is one area where heterochrony has been hypothesized to explain morphological differentiation among Plio-Pleistocene hominins. This hypothesis is evaluated here using geometric morphometric data to describe the ontogenetic shape trajectories of extant hominine distal femora and place Plio-Pleistocene hominins within that context. Results of multivariate statistical analyses showed that in both Homo and Gorilla, the shape of the distal femur changes significantly over the course of development, whereas that of Pan changes very little. Development of the distal femur of Homo is characterized by an elongation of the condyles, and a greater degree of enlargement of the medial condyle relative to the lateral condyle, whereas Gorilla are characterized by a greater degree of enlargement of the lateral condyle, relative to the medial. Early Homo and Australopithecus africanus fossils fell on the modern human ontogenetic shape trajectory and were most similar to either adult or adolescent modern humans while specimens of Australopithecus afarensis were more similar to Gorilla/Pan. These results indicate that shape differences among the distal femora of Plio-Pleistocene hominins and humans cannot be accounted for by heterochrony alone; heterochrony could explain a transition from the distal femoral shape of early Homo/A. africanus to modern Homo, but not a transition from A. afarensis to Homo. That change could be the result of genetic or epigenetic factors.

  2. Shape Ontogeny of the Distal Femur in the Hominidae with Implications for the Evolution of Bipedality

    Science.gov (United States)

    Tallman, Melissa

    2016-01-01

    Heterochrony has been invoked to explain differences in the morphology of modern humans as compared to other great apes. The distal femur is one area where heterochrony has been hypothesized to explain morphological differentiation among Plio-Pleistocene hominins. This hypothesis is evaluated here using geometric morphometric data to describe the ontogenetic shape trajectories of extant hominine distal femora and place Plio-Pleistocene hominins within that context. Results of multivariate statistical analyses showed that in both Homo and Gorilla, the shape of the distal femur changes significantly over the course of development, whereas that of Pan changes very little. Development of the distal femur of Homo is characterized by an elongation of the condyles, and a greater degree of enlargement of the medial condyle relative to the lateral condyle, whereas Gorilla are characterized by a greater degree of enlargement of the lateral condyle, relative to the medial. Early Homo and Australopithecus africanus fossils fell on the modern human ontogenetic shape trajectory and were most similar to either adult or adolescent modern humans while specimens of Australopithecus afarensis were more similar to Gorilla/Pan. These results indicate that shape differences among the distal femora of Plio-Pleistocene hominins and humans cannot be accounted for by heterochrony alone; heterochrony could explain a transition from the distal femoral shape of early Homo/A. africanus to modern Homo, but not a transition from A. afarensis to Homo. That change could be the result of genetic or epigenetic factors. PMID:26886416

  3. Bisphosphonates and Atypical Fractures of Femur

    Directory of Open Access Journals (Sweden)

    Tero Yli-Kyyny

    2011-01-01

    Full Text Available Bisphosphonates are the most widely prescribed medicines for the treatment of osteoporosis and have generally been regarded as well-tolerated and safe drugs. Since 2005, there have been numerous case reports about atypical fractures of the femur linked to long-term treatment of osteoporosis with bisphosphonates. Some attempts to characterize pathophysiology and epidemiology of these fractures have been published as well. However, as the American Society for Bone and Mineral Research (ASBMR concluded in their task force report, the subject warrants further studies.

  4. Periosteal osteoblastoma of the distal femur

    Energy Technology Data Exchange (ETDEWEB)

    Nakatani, Tetsuya; Yamamoto, Tetsuji; Akisue, Toshihiro; Marui, Takashi; Hitora, Toshiaki; Kawamoto, Teruya; Nagira, Keiko; Yoshiya, Shinichi; Kurosaka, Masahiro [Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe (Japan); Fujita, Ikuo; Matsumoto, Keiji [Department of Orthopaedic Surgery, Hyogo Medical Center for Adults, Akashi, Hyogo (Japan)

    2004-02-01

    Osteoblastomas located on the surface of the cortical bone, so-called periosteal osteoblastomas, are extremely rare. We report on a case of periosteal osteoblastoma arising from the posterior surface of the right distal femur in a 17-year-old man. Roentgenographic, computed tomographic, magnetic resonance imaging, and histologic features of the case are presented. Periosteal osteoblastoma should be radiologically and histologically differentiated from myositis ossificans, avulsive cortical irregularity syndrome, osteoid osteoma, parosteal osteosarcoma, periosteal osteosarcoma, and high-grade surface osteosarcoma. Although periosteal osteoblastoma is rare, this tumor should be included in the differential diagnosis of surface-type bone tumors. (orig.)

  5. Ipsilateral Fracture Shaft Femur with Neglected Dislocation of Prosthesis: A Case Report

    Directory of Open Access Journals (Sweden)

    Mantu Jain

    2013-10-01

    Full Text Available Introduction: Neglected hip dislocation is rare in today’s world and after prosthesis replacement even rarer finding. However such patients may not report to surgeons until they develop secondary complications. Management of such patient’s is a challenge to the treating surgeon and need to be tailored suiting to patient’s demands, expectations and constraints of financial resources. We did not find a similar case in the electronic and print media and therefore report this case which was innovatively managed. Case Report: A 60 year farmer presented with fracture shaft femur and ipsilateral dislocation prosthesis of right hip. He had a hemiarthroplasty done for fracture neck of femur in the past but used to walk with a lurch since he started to ambulate after discharge. However he was satisfied despite “some problems” which had caused shortening of his limb. The patient was informed of the various treatment options and their possible complications. He expressed his inability to afford a Total Hip Arthroplasty (THA at any stage and consented for other options discussed with him. The patient was positioned supine and adductor tenotomy done. Next he was positioned laterally and the fracture was fixed with heavy duty broad dynamic compression plate and screws. The wound was temporarily closed. Now through the previous scar via posterior approach the hip was exposed. The prosthesis was found to be firmly fixed to the proximal femur. The acetabulum was cleared with fibrous tissue. All attempts the prosthesis to relocate the prosthesis failed after several attempts and it was best decided to leave alone. Post operatively period was uneventful. At follow up he refused for any further manoeuvre in future inform of heavy traction and attempts to reduce the same. At one year when he was walking unaided and his X-rays showed that fracture had well united his SF-36 score was PCS – 49.6 and MCS – 51.9. Conclusion: Ipsilateral shaft femur fracture

  6. Differentially expressed genes strongly correlated with femur strength in rats

    OpenAIRE

    Alam, Imranul; Sun, Qiwei; Koller, Daniel L.; Liu, Lixiang; Liu, Yunlong; Edenberg, Howard J; Li, Jiliang; Foroud, Tatiana; Turner, Charles H.

    2009-01-01

    The region of chromosome 1q33–q54 harbors quantitative trait loci (QTL) for femur strength in COP×DA and F344×LEW F2 rats. The purpose of this study is to identify the genes within this QTL region that contribute to the variation in femur strength. Microarray analysis was performed using RNA extracted from femurs of COP, DA, F344 and LEW rats. Genes differentially expressed in the 1q33–q54 region among these rat strains were then ranked based on the strength of correlation with femur strength...

  7. Biomechanical properties of the mid-shaft femur in middle-aged hypophysectomized rats as assessed by bending test.

    Science.gov (United States)

    Bozzini, Clarisa; Picasso, Emilio O; Champin, Graciela M; Alippi, Rosa María; Bozzini, Carlos E

    2012-10-01

    Both stiffness and strength of bones are thought to be controlled by the "bone mechanostat". Its natural stimuli would be the strains of bone tissue (sensed by osteocytes) that are induced by both gravitational forces (body weight) and contraction of regional muscles. Body weight and muscle mass increase with age. Biomechanical performance of load-bearing bones must adapt to these growth-induced changes. Hypophysectomy in the rat slows the rate of body growth. With time, a great difference in body size is established between a hypophysectomized rat and its age-matched control, which makes it difficult to establish the real effect of pituitary ablation on bone biomechanics. The purpose of the present investigation was to compare mid-shaft femoral mechanical properties between hypophysectomized and weight-matched normal rats, which will show similar sizes and thus will be exposed to similar habitual loads. Two groups of 10 female rats each (H and C) were established. H rats were 12-month-old that had been hypophysectomized 11 months before. C rats were 2.5-month-old normals. Right femur mechanical properties were tested in 3-point bending. Structural (load-bearing capacity and stiffness), geometric (cross-sectional area, cortical sectional area, and moment of inertia), and material (modulus of elasticity and maximum elastic stress) properties were evaluated. The left femur was ashed for calcium content. Comparisons between parameters were performed by the Student's t test. Average body weight, body length, femur weight, femur length, and gastrocnemius weight were not significantly different between H and C rats. Calcium content in ashes was significantly higher in H than in C rats. Cross-sectional area, medullary area, and cross-sectional moment of inertia were higher in C rats, whereas cortical area did not differ between groups. Structural properties (diaphyseal stiffness, elastic limit, and load at fracture) were about four times higher in hypophysectomized rats

  8. Pindborg tumor in the distal femur.

    Science.gov (United States)

    Sussela, Alex Oliboni; Alves, Paulo Ricardo Picon; Silva, Vinicius Duval da; Bolze, Carlos Daniel de Garcia; Serafini, Osvaldo André

    2017-01-01

    To describe a case of possible diagnosis of Pindborg tumor on the distal femur. A 32-years-old female patient, a native of Bolivia, resident in Brazil, arrived to this service for tumor research in the right femur. After biopsies and resection of the lesion, the case was referred to analysis and consultancy in the United States. In a report of review by the Pathology Laboratory, it was characterized the histological appearance and immunohistochemical profile were characteristic of Pindborg tumor. Currently, the patient is being followed-up at the Orthopedics and Traumatology Department of this institution, and presents a good evolution. This study presents the case of a patient with a rare tumor that was investigated for an extensive period and through many tests. Pindborg tumor was suggested as a diagnostic hypothesis due to the characteristics and behavior of the neoplastic lesion. Although this lesion is more commonly observed in odontology, the neoplasia was compatible with the diagnosis. Therefore, despite the fact that this tumor has benign characteristics, long-term monitoring is necessary, given the high rate of tumor recurrence.

  9. Pindborg tumor in the distal femur

    Directory of Open Access Journals (Sweden)

    Alex Oliboni Sussela

    Full Text Available ABSTRACT To describe a case of possible diagnosis of Pindborg tumor on the distal femur. A 32-years-old female patient, a native of Bolivia, resident in Brazil, arrived to this service for tumor research in the right femur. After biopsies and resection of the lesion, the case was referred to analysis and consultancy in the United States. In a report of review by the Pathology Laboratory, it was characterized the histological appearance and immunohistochemical profile were characteristic of Pindborg tumor. Currently, the patient is being followed-up at the Orthopedics and Traumatology Department of this institution, and presents a good evolution. This study presents the case of a patient with a rare tumor that was investigated for an extensive period and through many tests. Pindborg tumor was suggested as a diagnostic hypothesis due to the characteristics and behavior of the neoplastic lesion. Although this lesion is more commonly observed in odontology, the neoplasia was compatible with the diagnosis. Therefore, despite the fact that this tumor has benign characteristics, long-term monitoring is necessary, given the high rate of tumor recurrence.

  10. [Effect of osteotomy metal plate anastomosis with the femur on stimulation of lower femur growth in children].

    Science.gov (United States)

    Wasilewski, K

    2001-01-01

    increase in length during the first 12 months from surgery; (7) Fixation of the osteotomy of the proximal femur in children may be one of the causes of enhancement of growth of the operated extremity. Early removal of the fixation device after healing of the osteotomy may arrest further growth of the extremity; (8) Coexistence of Ehlers-Danlos syndrome does not essentially influence enhancement of growth of the operated extremity.

  11. Population-based epidemiology and incidence of distal femur fractures

    DEFF Research Database (Denmark)

    Elsoe, Rasmus; Ceccotti, Adriano Axel; Larsen, Peter

    2017-01-01

    The literature lacks recent epidemiological studies on the incidence, trauma mechanism and fracture classification of distal femur fractures. The aim of the present study was to provide up-to-date information concerning the incidence of distal femur fractures in a large and complete population...

  12. bilateral recon nailing of comminuted fracture femur in a severely ...

    African Journals Online (AJOL)

    2012-09-06

    Sep 6, 2012 ... Severely comminuted fractures of the femur can be challenging injuries to manage. The incidence of these ... (KNH). Injuries identified included almost identical bilateral fracture femur consisting of high subtrochanteric fracture with .... nailing for ipsilateral femoral neck and shaft fractures. Strategies Trauma ...

  13. Treatment of femur shaft fractures using Perkins' traction at Addis ...

    African Journals Online (AJOL)

    Objectives: To evaluate the outcomes of Perkins' technique in the treatment of adult femur shaft fractures from October 2007 – May 2009. Faculty of Medicine, Black-Lion Hospital (BLH), Addis Ababa University, Ethiopia, The study also aimed at looking into the spectrum of femur shaft fractures referred to BLH. Design: This ...

  14. Geometrization of Quantum Mechanics

    OpenAIRE

    Carinena, J. F.; Clemente-Gallardo, J.; Marmo, G.

    2007-01-01

    We show that it is possible to represent various descriptions of Quantum Mechanics in geometrical terms. In particular we start with the space of observables and use the momentum map associated with the unitary group to provide an unified geometrical description for the different pictures of Quantum Mechanics. This construction provides an alternative to the usual GNS construction for pure states.

  15. Proximal femoral fractures: Principles of management and review of literature

    Science.gov (United States)

    Mittal, Ravi; Banerjee, Sumit

    2012-01-01

    Purpose The purpose of this study was to review the principles involved in the management of proximal femoral fractures as reported in the literature. Methods: A medical literature search in the MEDLINE (PubMed) and Cochrane database was undertaken to review strategies and principles in proximal femoral fracture treatment. Randomized control trials and meta analysis were given preference while case reports/small series were rejected. Results and conclusions: Early anatomical reduction and surgical fixation remains the best option to reduce the risk of complications like non-union and avascular necrosis in treating fracture neck femurs. Cancellous screws continue to be the preferred treatment for fixation of neck femur fractures in younger population until the benefit of using sliding hip screws is validated by large multicentric studies. In the geriatric age group, early prosthetic replacement brings down the mortality and morbidity associated with neck femur fractures. Sliding hip screw (DHS) is the best available option for stable inter trochanteric fractures. The use of intramedullary nails e.g. PFN is beneficial in treating inter trochanteric fractures with comminution and loss of lateral buttress. Intramedullary implants have been proven to have increased success rates in subtrochanteric fractures and should be preferred over extramedullary plate fixation systems. PMID:25983451

  16. Three-dimensional microarchitecture of the proximal femur in osteoarthritis and rheumatoid arthritis

    DEFF Research Database (Denmark)

    Wang, B. L.; Ding, Ming; Overgaard, Søren

    2015-01-01

    BACKGROUND: The main reason for reducing the life of joint prosthesis is prosthetic loosening. In addition to prosthesis design, surgical technique, prosthetic material and the resulting wear particles, bone quality also plays a very important role in prosthetic loosening. Bone tissue microstruct...

  17. Double plating in Vancouver type B1 periprosthetic proximal femur fractures: A biomechanical study.

    Science.gov (United States)

    Wähnert, Dirk; Grüneweller, Niklas; Gehweiler, Dominic; Brunn, Benjamin; Raschke, Michael J; Stange, Richard

    2017-02-01

    Periprosthetic hip fractures are an increasing problem in modern orthopedic and trauma surgery. Many options for the operative treatment are available to the surgeon ranging from modern variable angular systems to standard plates, screws, and cerclages. However, there is no gold standard and therefore, the aim of this study, was to investigate the biomechanical characteristics of double plating versus a lateral standard plate in a Vancouver B1 fracture model. Ten 4th generation composite femora were used to implant cementless total hip prosthesis and create Vancouver B1 periprosthetic fractures. Afterwards, the osteotomies were fixed using the locking compression plate in combination with the locking attachment plate (LCP, LAP, DePuy Synthes, Solothurn, Switzerland)-group I. Group II additionally achieved a 5-hole 4.5/5.0 mm LCP anteriorly. Each construct was cyclically loaded to failure in axial compression. Axial construct stiffness was 50.87 N/mm (SD 1.61) for group I compared to 738.68 N/mm (SD 94.8) for group II, this difference was statistically significant (p = 0.016). The number of cycles to failure was also significant higher for group II (2,375 vs. 13,000 cycles; p = 0.016). Double plating can significantly increase construct stiffness and stability, and thus, is an option in the treatment of complex periprosthetic fractures, in revision surgery and for patients with the inability to partial weight bear. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:234-239, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  18. Disproportional geometry of the proximal femur in patients with Turner syndrome: a cross-sectional study

    DEFF Research Database (Denmark)

    Nissen, Nis; Gravholt, Claus H; Abrahamsen, Bo

    2007-01-01

    OBJECTIVE: Patients with Turner syndrome (TS) have altered growth and increased risk of osteoporosis due to oestrogen deficiency and possibly a host of other factors. Thus, TS patients have a 4.9-fold increased risk of femoral neck fractures. Most patients are treated with oestrogen during puberty...... with healthy controls. PATIENTS: The study population comprised 58 patients with TS (aged 22-67 years) and 60 age-matched healthy women (aged 21-65 years). MEASUREMENTS: Hip axis length (HAL), neck width (NW), neck shaft angle (NSA), and femoral head-radius (HR) on dual-energy X-ray absorptiometry (DXA) screen...... and adolescence to facilitate pubertal development and prevent secondary osteoporosis. The geometry of the hip is a predictor for hip fractures independent of bone mineral density (BMD). The purpose of the present study was to investigate the variation of the geometry of the hip in patients with TS in comparison...

  19. Disproportional geometry of the proximal femur in patients with Turner syndrome: a cross-sectional study

    DEFF Research Database (Denmark)

    Nissen, N; Gravholt, C H; Abrahamsen, B

    2007-01-01

    with healthy controls. PATIENTS: The study population comprised 58 patients with TS (aged 22-67 years) and 60 age-matched healthy women (aged 21-65 years). MEASUREMENTS: Hip axis length (HAL), neck width (NW), neck shaft angle (NSA), and femoral head-radius (HR) on dual-energy X-ray absorptiometry (DXA) screen...... for differences in height, HAL was not significantly different (9.4 +/- 0.5 vs. 9.5 +/- 0.5 cm; NS) in TS compared with controls while NW was significantly increased (3.5 +/- 0.4 cm vs. 3.3 +/- 0.2 cm, P NSA was similar (129 +/- 4 degrees vs. 130 +/- 4 degrees , NS), and HR was significantly decreased...

  20. Pre-operative traction for fractures of the proximal femur in adults.

    Science.gov (United States)

    Parker, M J; Handoll, H H G

    2006-07-19

    Following a hip fracture, traction may be applied to the injured limb before surgery. To evaluate the effects of traction applied to the injured limb prior to surgery for a fractured hip. Different methods of applying traction (skin or skeletal) were considered. We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (March 2006), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to March 2006), EMBASE (1988 to 2006 Week 11), CINAHL (1982 to March 2006), the UK National Research Register (Issue 1, 2006), conference proceedings and reference lists of articles. All randomised or quasi-randomised trials comparing either skin or skeletal traction with no traction, or skin with skeletal traction for patients with an acute hip fracture prior to surgery. Both authors independently assessed trial quality and extracted data. Additional information was sought from all trialists. Wherever appropriate and possible, data were pooled. Ten randomised trials, mainly of moderate quality, involving a total of 1546 predominantly elderly patients with hip fractures, were identified and included in the review. Nine trials compared traction with no traction. Although limited data pooling was possible, overall this provided no evidence of benefit from traction, either in the relief of pain before surgery or ease of fracture reduction or quality of fracture reduction at time of surgery. One of these trials included both skin and skeletal traction groups. This trial and one other compared skeletal traction with skin traction and found no important differences between these two methods, although the initial application of skeletal traction was noted as being more painful and more costly. From the evidence available, the routine use of traction (either skin or skeletal) prior to surgery for a hip fracture does not appear to have any benefit. However, the evidence is also insufficient to rule out the potential advantages for traction, in particular for specific fracture types, or to confirm additional complications due to traction use. Further, high quality trials would be required to confirm or refute the absence of benefits of traction.

  1. Structural Analysis and Optimization of the Support Device Used for a Proximal Fracture of the Femur

    Science.gov (United States)

    2008-12-01

    and 2700 N in the S/I direction. The final loading condition involves the forces of climbing a stair . These forces are applied on the femoral head...perform actions like walk, climbing stairs or lifting. In a dynamic locking distal-screw configuration, the two screws separated by 20 mm yielded the... biomechanics , fluid flow and many more. FEA /FEM are also benefactors of the advancement of technology. As computer processing advancements take place, it

  2. Multiset proximity spaces

    Directory of Open Access Journals (Sweden)

    A. Kandil

    2016-10-01

    Full Text Available A multiset is a collection of objects in which repetition of elements is essential. This paper is an attempt to explore the theoretical aspects of multiset by extending the notions of compact, proximity relation and proximal neighborhood to the multiset context. Examples of new multiset topologies, open multiset cover, compact multiset and many identities involving the concept of multiset have been introduced. Further, an integral examples of multiset proximity relations are obtained. A multiset topology induced by a multiset proximity relation on a multiset M has been presented. Also the concept of multiset δ- neighborhood in the multiset proximity space which furnishes an alternative approach to the study of multiset proximity spaces has been mentioned. Finally, some results on this new approach have been obtained and one of the most important results is: every T4- multiset space is semi-compatible with multiset proximity relation δ on M (Theorem 5.10.

  3. A Babylonian Geometrical Algebra.

    Science.gov (United States)

    Bidwell, James K.

    1986-01-01

    A possible method of derivation of prescriptions for solving problems, found in Babylonian cuneiform texts, is presented. It is a kind of "geometric algebra" based mainly on one figure and the manipulation of or within various areas and segments. (MNS)

  4. Geometric and engineering drawing

    CERN Document Server

    Morling, K

    2010-01-01

    The new edition of this successful text describes all the geometric instructions and engineering drawing information that are likely to be needed by anyone preparing or interpreting drawings or designs with plenty of exercises to practice these principles.

  5. Differential geometric structures

    CERN Document Server

    Poor, Walter A

    2007-01-01

    This introductory text defines geometric structure by specifying parallel transport in an appropriate fiber bundle and focusing on simplest cases of linear parallel transport in a vector bundle. 1981 edition.

  6. Further improving geometric fitting

    OpenAIRE

    Kanatani, Kenichi

    2005-01-01

    We give a formal definition of geometric fitting in a way that suits computer vision applications. We point out that the performance of geometric fitting should be evaluated in the limit of small noise rather than in the limit of a large number of data as recommended in the statistical literature. Taking the KCR lower bound as an optimality requirement and focusing on the linearized constraint case, we compare the accuracy of Kanatani's renormalization with maximum likelihood (ML) approaches ...

  7. Proximal Femoral Geometry and the Risk of Fractures: Literature Review

    Directory of Open Access Journals (Sweden)

    N.V. Grygorieva

    2016-05-01

    Full Text Available This article presents the literature review of the impact of the upper third of the femur geometry (hip axis length, femoral neck angle, inter-trochanteric length, horizontal offset, thickness of the cortical bone, etc. on the risk of fractures. The article demonstrates the capabilities of techniques for measurement of hip geometry, namely conventional X-ray of pelvic bones, dual-energy X-ray absorptiometry, computed tomography. Possible correlation is shown between some genetic markers and features of the geometry of the upper third of the femur. Also, there are presented the results of own researches of age and sex characteristics of proximal hip geometry parameters in patients without fractures, as well as in patients of older age groups with internal and extraarticular femoral fractures.

  8. Hierarchies of geometric entanglement

    Science.gov (United States)

    Blasone, M.; Dell'Anno, F.; de Siena, S.; Illuminati, F.

    2008-06-01

    We introduce a class of generalized geometric measures of entanglement. For pure quantum states of N elementary subsystems, they are defined as the distances from the sets of K -separable states (K=2,…,N) . The entire set of generalized geometric measures provides a quantification and hierarchical ordering of the different bipartite and multipartite components of the global geometric entanglement, and allows discrimination among the different contributions. The extended measures are applied to the study of entanglement in different classes of N -qubit pure states. These classes include W and Greenberger-Horne-Zeilinger (GHZ) states, and their symmetric superpositions; symmetric multimagnon states; cluster states; and, finally, asymmetric generalized W -like superposition states. We discuss in detail a general method for the explicit evaluation of the multipartite components of geometric entanglement, and we show that the entire set of geometric measures establishes an ordering among the different types of bipartite and multipartite entanglement. In particular, it determines a consistent hierarchy between GHZ and W states, clarifying the original result of Wei and Goldbart that W states possess a larger global entanglement than GHZ states. Furthermore, we show that all multipartite components of geometric entanglement in symmetric states obey a property of self-similarity and scale invariance with the total number of qubits and the number of qubits per party.

  9. Safe zones and a technical guide for cerclage wiring of the femur: a computed topographic angiogram (CTA) study.

    Science.gov (United States)

    Apivatthakakul, Theerachai; Siripipattanamongkol, P; Oh, Chang-Wug; Sananpanich, K; Phornphutkul, C

    2017-09-27

    Cerclage wiring for reduction of complex femoral shaft fractures can create iatrogenic vascular injury. To describe the anatomical relation of blood vessels to the femur and develop a technical guide for safe passage of cerclage wire. CT lower-limb angiographs (CTA) of 80 patients were reviewed and analysed to identify the superficial femoral artery (SFA) and the deep femoral artery (DFA) as well as the relation of those arteries to the femoral cortex. The total length of the femur was measured and divided into eight equal segments (seven levels). At each level, the medial half of the femur was divided into eight sectors labelled A through H and the position of the SFA and DFA was recorded. The shortest distance between the femoral cortex and the SFA and DFA at each level was measured. The data was analysed using STATA version 10.0. The average total femoral length from the tip of greater trochanter to lateral joint line was 402.98 ± 26.16 cm. The average distances from the SFA to the femur (d1) for levels 1 through 7 were 37.20 ± 5.0, 32.09 ± 4.74, 27.13 ± 4.19, 27.71 ± 5.46, 23.71 ± 4.40, 13.63 ± 3.59 and 10.08 ± 3.09 mm, respectively. The average distances between the DFA and the femur (d2) for levels 1 through 3 were 26.70 ± 4.13, 14.76 ± 3.27 and 9.58 ± 3.79 mm, respectively. The position of the SFA is located in sectors B through E at levels 1-3 and in sectors E through H at levels 4-7 and the position of the DFA located in sectors B through F at levels 1-3. Cerclage wiring should be started from the posterior intermuscular septum at the linea aspera. The safe area is the proximal half (midshaft) of the femur where the SFA and DFA lie at a safe distance from the femur. Between the midshaft and the distal 1/4, insertion of the passer must be done meticulously with the tip kept close to posteromedial cortex. Below the distal 1/4, the tip of the passer should be kept close to the posterior cortex to avoid injury to the SFA and

  10. Macrodamage Accumulation Model for a Human Femur

    Directory of Open Access Journals (Sweden)

    Farah Hamandi

    2017-01-01

    Full Text Available The objective of this study was to more fully understand the mechanical behavior of bone tissue that is important to find an alternative material to be used as an implant and to develop an accurate model to predict the fracture of the bone. Predicting and preventing bone failure is an important area in orthopaedics. In this paper, the macrodamage accumulation models in the bone tissue have been investigated. Phenomenological models for bone damage have been discussed in detail. In addition, 3D finite element model of the femur prepared from imaging data with both cortical and trabecular structures is delineated using MIMICS and ANSYS® and simulated as a composite structure. The damage accumulation occurring during cyclic loading was analyzed for fatigue scenario. We found that the damage accumulates sooner in the multiaxial than in the uniaxial loading condition for the same number of cycles, and the failure starts in the cortical bone. The damage accumulation behavior seems to follow a three-stage growth: a primary phase, a secondary phase of damage growth marked by linear damage growth, and a tertiary phase that leads to failure. Finally, the stiffness of the composite bone comprising the cortical and trabecular bone was significantly different as expected.

  11. Mechanical evaluation of large-size fourth-generation composite femur and tibia models.

    Science.gov (United States)

    Gardner, Matthew P; Chong, Alexander C M; Pollock, Anthony G; Wooley, Paul H

    2010-03-01

    Composite analogue bone models provide consistent geometric and structural properties that represent a valuable asset in a range of biomechanical analyses and testing procedures. The objective of this study was to evaluate the diaphyseal structural properties of the large-size Fourth-Generation composite analogue femur and tibia models concentrated on mechanical behaviors under axial compression, bending and torsion. Thirty of each large-size composite analogue models (femora and tibiae) were tested under medial-lateral four-point bending, anterior-posterior four-point bending, axial compression and external rotational torque to evaluate flexural rigidity, axial stiffness, torsional rigidity and ultimate failure strength. The composite femur was tested under torsion at both the femoral neck and the mid-diaphyseal areas. Large-size Fourth-Generation composite replicate bones exhibited intra-specimen variations under 10% for all cases and was also found to perform within the biological range of healthy adult bones (age: evaluated and advanced our overall understanding of the capacity of composite analogue bone models mimic the structural properties of average healthy adult human bones.

  12. Proximal Probes Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Proximal Probes Facility consists of laboratories for microscopy, spectroscopy, and probing of nanostructured materials and their functional properties. At the...

  13. Retrograde intramedullary nailing for distal femur fracture with osteoporosis.

    Science.gov (United States)

    Kim, Jihyeung; Kang, Seung-Baik; Nam, Kyungpyo; Rhee, Seung Hwan; Won, Jong Won; Han, Hyuk-Soo

    2012-12-01

    The incidence of distal femur fracture in the elderly has been increasing recently, and commonly occurs with osteoporosis. Retrograde intramedullary nailing has been considered a good surgical option for distal femur fracture. The purpose of the present study was to present our surgical results with retrograde intramedullary nailing for distal femur fractures with osteoporosis. Thirteen patients diagnosed with extra-articular distal femur fracture and osteoporosis and managed with retrograde intramedullary nailing were retrospectively reviewed. Cement augmentation was used in four patients, shape memory alloy was used in eight patients and both were used in one patient. All patients were followed up for more than 2 years. Radiologic alignments were scored and Tegner and the Lysholm activity score was used for a functional assessment. The average time to clinical union was 13 weeks (range, 10 to 15 weeks). In 12 of our cases, the total alignment scores were excellent. At the last follow-up, the mean range of motion was 116° (range, 110° to 125°). The average functional score at postoperative 1 year was 2.6 (range, 1 to 5). Retrograde intramedullary nailing is a good surgical option for distal femur fracture with osteoporosis. Cement augmentation and shape memory alloy can also be used for added mechanical stability. This surgical technique is very useful for distal femur fracture with osteoporosis as it promotes fracture healing and early rehabilitation.

  14. Sex Assessment Using the Femur and Tibia in Medieval Skeletal Remains from Ireland: Discriminant Function Analysis.

    Science.gov (United States)

    Novak, Mario

    2016-04-01

    Sex determination based on discriminant function analysis of skeletal measurements is probably the most effective method for assessment of sex in archaeological and contemporary populations due to various reasons, but it also suffers from limitations such as population specificity. In this paper standards for sex assessment from the femur and tibia in the medieval Irish population are presented. Six femoral and six tibial measurements obtained from 56 male and 45 female skeletons were subjected to discriminant function analysis. Average accuracies obtained by this study range between 87.1 and 97%. The highest level of accuracy (97%) was achieved when using combined variables of the femur and tibia (maximum diameter of femoral head and circumference at tibial nutrient foramen), as well as two variables of the tibia (proximal epiphyseal breadth and circumference at nutrient foramen). Discriminant functions using a single variable provided accuracies between 87.1 and 96% with the circumference at the level of the tibial nutrient foramen providing the best separation. High accuracy rates obtained by this research correspond to the data recorded in other studies thus confirming the importance of discriminant function analysis in assessment of sex in both archaeological and forensic contexts.

  15. Reconstructive vascular surgery in rotationplasty for malignant tumors of the femur.

    Science.gov (United States)

    Sidiropoulos, A; Tjan, T D; Soeparwata, R; Wuismann, P; Winkelmann, W; Scheld, H H

    1994-12-01

    The rotationplasty procedure of the femur, as first described by Borrgreve, is the functional improvement of an abnormally shortened lower limb. In the last 15 years this procedure has been used in its original form and as modification for tumors of the femur and proximal tibia. The reconstruction of the femoral vessels as an important part of the operation has not enough been accentuated. Principally two types of reconstructions can be performed: the vessels are dissected in the adductor canal or a segmental resection and reanastomosis are performed. Between January 1990 and April 1993 classical and modified rotationplasties were performed for malignant tumors in 34 patients in our institution. In all cases a segmental femoral vessel resection with end-to-end anastomosis were performed. No intra- and postoperative vascular related complications occurred. The authors emphasize the advantage of this method: reanastomosing resected femoral vessels by experienced vascular surgeons is a save, time-saving method. In addition, the radicality of the operation increases in order to obtain excellent long term results.

  16. Proximal focal femoral deficiency: evaluation by MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Biko, David M. [National Naval Medical Center, Department of Radiology, Bethesda, MD (United States); Uniformed Services University of Health Sciences, Department of Radiology and Radiological Sciences, Bethesda, MD (United States); Davidson, Richard [The Children' s Hospital of Philadelphia, Department of Orthopedic Surgery, Philadelphia, PA (United States); Pena, Andres; Jaramillo, Diego [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2012-01-15

    Proximal focal femoral deficiency (PFFD) is a rare congenital anomaly characterized by abnormal development of the proximal femur. The most common radiographic classification (Aitken) does not evaluate the cartilaginous and soft-tissue abnormalities. To demonstrate MR findings of PFFD focusing on features not seen with radiographs. Nine MR examinations of the hip and femurs of seven children with PFFD were retrospectively reviewed. Imaging was quantitatively and qualitatively assessed comparing the affected limb to the contralateral limb and age-matched controls. The children were classified via the Aitken classification. All children had at least mild acetabular dysplasia, and one type D patient had no acetabulum. MR demonstrated that 4/6 children had labral hypertrophy with a decreased distance from the greater trochanter to the acetabular rim, suggesting impingement (P < 0.05). The proximal femoral physis was abnormal in all cases. The connection between the femoral head and shaft if present was fibrous or fibrocartilaginous. MRI can help in evaluation of PFFD by defining the anatomy. MR demonstrates features of the acetabulum and cartilaginous femoral epiphysis and depicts ligamentous abnormalities of the knee. (orig.)

  17. Algebraic geometric codes

    Science.gov (United States)

    Shahshahani, M.

    1991-01-01

    The performance characteristics are discussed of certain algebraic geometric codes. Algebraic geometric codes have good minimum distance properties. On many channels they outperform other comparable block codes; therefore, one would expect them eventually to replace some of the block codes used in communications systems. It is suggested that it is unlikely that they will become useful substitutes for the Reed-Solomon codes used by the Deep Space Network in the near future. However, they may be applicable to systems where the signal to noise ratio is sufficiently high so that block codes would be more suitable than convolutional or concatenated codes.

  18. Treatment outcomes of intertrochanteric femur fractures treated with DLT™ nail

    Directory of Open Access Journals (Sweden)

    Mehmet Arıcan

    2015-12-01

    Full Text Available Objective: Intramedullary nails frequently use in proximal femur fractures. In this study, 49 patients with intertrochanteric fractures were evaluated clinical and radiological results treated with dyna locking trochanteric (DLT™ nail retrospectively. Methods: Twenty-two (44.9% patients were male and 27 (55.1% patients were female. Mean age was 74.29±1.98 (28-99 years and Followed up for a mean of 14.35±3.43 (9-24 months. Thirty-seven (75.6% of the fractures resulted from simple falls while 6 (12.2% caused from traffic accidents and 6 (12.2% fall down from height. There were 24 (49.0% left and 25 (51.0% right lower extremities fractured. According to Orthopaedic Trauma Association classification system; 21 (42.9%, 21 (42.9% and 7 (14.2% fractures were classified as 31A1, 31A2, and 31A3 respectively. One (2.0% patient had claviculae fracture, 3 (6.1% patients had radius distal fracture and 1 (2.0% patient had total knee arthroplasty. After surgery, X-ray was used for radiological results and functional outcomes were evaluated according to the Harris hip scoring system. Results: The average waiting time for the surgery was 2.02±0.18 (1-7 days and hospitalization time was 6.23±0.29 (4-15 days. Mean fracture healing time was 11.74±1.82 (8-15 weeks. Three patients had screw cut-out in the follow-up time and performed hemiarthroplasty. The average Harris hip score was 88.02±1.21 (42-97 points and included 29 (59.2% excellent cases, 17 (34.7% good and 3 (6.1% poor. Conclusion: DLT ™ nail is a safe and successful method because of low complication rates, and capability of detection.

  19. Tumeur à cellules géantes du fémur proximal traitée par ...

    African Journals Online (AJOL)

    The authors report the case of a giant cell tumor grade 1 of the proximal femur, diagnosed in a young patient of 18 years. The diagnosis was suspected on a standard x-ray complemented by MRI, it was confirmed on histological examination after biopsy. The tumor was a metaphyseal-epiphyseal location above the level of ...

  20. Mahavira's Geometrical Problems

    DEFF Research Database (Denmark)

    Høyrup, Jens

    2004-01-01

    Analysis of the geometrical chapters Mahavira's 9th-century Ganita-sara-sangraha reveals inspiration from several chronological levels of Near-Eastern and Mediterranean mathematics: (1)that known from Old Babylonian tablets, c. 1800-1600 BCE; (2)a Late Babylonian but pre-Seleucid Stratum, probabl...

  1. Design and Development of Potential Tissue Engineering Scaffolds from Structurally Different Longitudinal Parts of a Bovine-Femur

    Science.gov (United States)

    Pramanik, Sumit; Pingguan-Murphy, Belinda; Cho, Jongman; Osman, Noor Azuan Abu

    2014-07-01

    The complex architecture of the cortical part of the bovine-femur was examined to develop potential tissue engineering (TE) scaffolds. Weight-change and X-ray diffraction (XRD) results show that significant phase transformation and morphology conversion of the bone occur at 500-750°C and 750-900°C, respectively. Another breakthrough finding was achieved by determining a sintering condition for the nucleation of hydroxyapatite crystal from bovine bone via XRD technique. Scanning electron microscopy results of morphological growth suggests that the concentration of polymer fibrils increases (or decreases, in case of apatite crystals) from the distal to proximal end of the femur. Energy-dispersive analysis of X-ray, Fourier transform infrared, micro-computer tomography, and mechanical studies of the actual composition also strongly support our microscopic results and firmly indicate the functionally graded material properties of bovine-femur. Bones sintered at 900 and 1000°C show potential properties for soft and hard TE applications, respectively.

  2. Submuscular bridge plating for length-unstable, pediatric femur fractures.

    Science.gov (United States)

    Samora, Walter P; Guerriero, Michael; Willis, Leisel; Klingele, Kevin E

    2013-12-01

    Submuscular bridge plating has become an acceptable method of treatment for pediatric femur fractures. The purpose of our study was to describe a technique for submuscular bridge plating and review a series of consecutive, length-unstable, pediatric femur fractures treated at a single institution with this technique. We performed a query of hospital records from January 4, 2006, to May 10, 2011, to identify length-unstable femur fractures treated with submuscular bridge plating by 5 pediatric surgeons. Included were patients treated with submuscular bridge plating for a femur fracture. Excluded were patients with incomplete medical records, inadequate radiographs, or follow-up femur fractures. There were 15 left femurs and 18 right femurs, including 1 bilateral fracture patient. Fracture pattern was composed of 13 comminuted, 5 spiral, 9 long oblique, and 6 short oblique. Mechanisms of injury included: fall from height (8), recreation (23), and MVA (2). Mean time for full weightbearing was 8.1 weeks (range, 3 to 17.6 wk). All patients were radiographically healed by their 12-week assessment. There were no intraoperative complications. Implant removal occurred in 26 patients. There were 2 cases of a broken screw discovered upon implant removal. The remnant screw was not removed in either case. The mean follow-up time for those with implant removal was 43.6 weeks (range, 27 to 83 wk). The 11 patients without implant removal had a mean follow-up time of 38.6 weeks (range, 31.6 to 50 wk). There were no cases of varus or valgus malalignment >10 degrees. One patient experienced implant irritation. There were no cases of wound infections. Our technique of surgical intervention has simplified both implantation and removal, and produced comparable and excellent healing rates, low complication rates, and early return to full weightbearing. Level IV, case series.

  3. Evaluation of bone deformities of the femur, tibia, and patella in Toy Poodles with medial patellar luxation using computed tomography.

    Science.gov (United States)

    Yasukawa, Shinji; Edamura, Kazuya; Tanegashima, Koji; Seki, Mamiko; Teshima, Kenji; Asano, Kazushi; Nakayama, Tomohiro; Hayashi, Kei

    2016-01-01

    To evaluate morphological parameters of the femur, tibia, and patella in Toy Poodles with medial patellar luxation (MPL) using three-dimensional (3D) computed tomography (CT) and to compare these parameters between radiography and CT. Thirty-five hindlimbs of Toy Poodles were divided into normal and grade 2 and 4 MPL groups. The anatomical and mechanical lateral proximal femoral angle, anatomical and mechanical lateral distal femoral angle (aLDFA, mLDFA), femoral varus angle (FVA), inclination of the femoral head angle, procurvation angle, anteversion angle (AA), frontal angle of the femoral neck, mechanical medial proximal or distal tibial angle, mechanical cranial proximal or distal tibial angle, tibial plateau angle, tibial torsion angle (TTA), Z angle, relative tibial tuberosity width, ratio of the medial distance of tibial tuberosity to the proximal tibial width (MDTT/PTW), patella size, and the patellar ligament length: patellar length (L:P) ratio were evaluated on radiography and 3D CT. The aLDFA, mLDFA, FVA, and TTA were significantly larger and the AA, MDTT/PTW, and patella were significantly smaller in the grade 4 MPL group. There were significant differences in many parameters between imaging tools, and CT was considered less susceptible to potential artefacts and rotational deformities. Toy Poodles with grade 4 MPL had significant femoral varus deformity, medial displacement of the tibial tuberosity, internal torsion of the proximal tibia, and hypoplasia of the patella.

  4. Biological plating of comminuted fractures of femur and tibia

    Directory of Open Access Journals (Sweden)

    Mohammad Javdan

    2007-08-01

    Full Text Available

    BACKGROUND: The treatment of comminuted fractures in long bones has continued to be a problem in orthopedic surgery. Recently, fixation without exploration of the fracture site, known as "biologic fixation”, has been introduced. This study was performed to assess the results and complications of this method for the treatment of comminuted fractures of the tibia and femur.
    METHODS: The study included 41 patients with comminuted fractures of the tibia and femur treated with biologic plating from 2003 to 2006 (25 femur fractures and 16 tibial fractures. After biological fixation joint motion was started but weight bearing was avoided until radiographic evidence of union was shown.
    RESULTS: The mean time of union in the tibial fractures was 19 ± 2 weeks and 17 ± 2 weeks for the femur fractures. All patients had fracture union without any infection, non-union or implant failure. In one patient with a femur fracture there was a 10° internal rotation deformity. Two of the femoral fractures had shortening of 1 cm, and one patient had shortening of about 2 cm. Compared to similar studies, all results were statistically significant (P<0.05.
    CONCLUSIONS: The biologic plating method is a safe, simple and effective method of fixation for comminuted fractures of long bones. It has a high rate of union with minimal complications.
    KEY WORDS: Biological fixation, plate, comminuted fracture.

  5. Differentially expressed genes strongly correlated with femur strength in rats

    Science.gov (United States)

    Alam, Imranul; Sun, Qiwei; Koller, Daniel L.; Liu, Lixiang; Liu, Yunlong; Edenberg, Howard J.; Li, Jiliang; Foroud, Tatiana; Turner, Charles H.

    2011-01-01

    The region of chromosome 1q33–q54 harbors quantitative trait loci (QTL) for femur strength in COP×DA and F344×LEW F2 rats. The purpose of this study is to identify the genes within this QTL region that contribute to the variation in femur strength. Microarray analysis was performed using RNA extracted from femurs of COP, DA, F344 and LEW rats. Genes differentially expressed in the 1q33–q54 region among these rat strains were then ranked based on the strength of correlation with femur strength in F2 animals derived from these rats. A total of 214 genes in this QTL region were differentially expressed among all rat strains, and 81 genes were found to be strongly correlated (r2>0.50) with femur strength. Of these, 12 candidate genes were prioritized for further validation, and 8 of these genes (Ifit3, Ppp2r5b, Irf7, Mpeg1, Bloc1s2, Pycard, Sec23ip, and Hps6) were confirmed by quantitative PCR (qPCR). Ingenuity Pathway Analysis suggested that these genes were involved in interferon alpha, nuclear factor-kappa B (NFkB), extracellular signal-related kinase (ERK), hepatocyte nuclear factor 4 alpha (HNF4A) and tumor necrosis factor (TNF) pathways. PMID:19482074

  6. Curvature reduces bending strains in the quokka femur

    Directory of Open Access Journals (Sweden)

    Kyle McCabe

    2017-03-01

    Full Text Available This study explores how curvature in the quokka femur may help to reduce bending strain during locomotion. The quokka is a small wallaby, but the curvature of the femur and the muscles active during stance phase are similar to most quadrupedal mammals. Our hypothesis is that the action of hip extensor and ankle plantarflexor muscles during stance phase place cranial bending strains that act to reduce the caudal curvature of the femur. Knee extensors and biarticular muscles that span the femur longitudinally create caudal bending strains in the caudally curved (concave caudal side bone. These opposing strains can balance each other and result in less strain on the bone. We test this idea by comparing the performance of a normally curved finite element model of the quokka femur to a digitally straightened version of the same bone. The normally curved model is indeed less strained than the straightened version. To further examine the relationship between curvature and the strains in the femoral models, we also tested an extra-curved and a reverse-curved version with the same loads. There appears to be a linear relationship between the curvature and the strains experienced by the models. These results demonstrate that longitudinal curvature in bones may be a manipulable mechanism whereby bone can induce a strain gradient to oppose strains induced by habitual loading.

  7. Dynamics in geometrical confinement

    CERN Document Server

    Kremer, Friedrich

    2014-01-01

    This book describes the dynamics of low molecular weight and polymeric molecules when they are constrained under conditions of geometrical confinement. It covers geometrical confinement in different dimensionalities: (i) in nanometer thin layers or self supporting films (1-dimensional confinement) (ii) in pores or tubes with nanometric diameters (2-dimensional confinement) (iii) as micelles embedded in matrices (3-dimensional) or as nanodroplets.The dynamics under such conditions have been a much discussed and central topic in the focus of intense worldwide research activities within the last two decades. The present book discusses how the resulting molecular mobility is influenced by the subtle counterbalance between surface effects (typically slowing down molecular dynamics through attractive guest/host interactions) and confinement effects (typically increasing the mobility). It also explains how these influences can be modified and tuned, e.g. through appropriate surface coatings, film thicknesses or pore...

  8. Geometric group theory

    CERN Document Server

    Bestvina, Mladen; Vogtmann, Karen

    2014-01-01

    Geometric group theory refers to the study of discrete groups using tools from topology, geometry, dynamics and analysis. The field is evolving very rapidly and the present volume provides an introduction to and overview of various topics which have played critical roles in this evolution. The book contains lecture notes from courses given at the Park City Math Institute on Geometric Group Theory. The institute consists of a set of intensive short courses offered by leaders in the field, designed to introduce students to exciting, current research in mathematics. These lectures do not duplicate standard courses available elsewhere. The courses begin at an introductory level suitable for graduate students and lead up to currently active topics of research. The articles in this volume include introductions to CAT(0) cube complexes and groups, to modern small cancellation theory, to isometry groups of general CAT(0) spaces, and a discussion of nilpotent genus in the context of mapping class groups and CAT(0) gro...

  9. Gravity, a geometrical course

    CERN Document Server

    Frè, Pietro Giuseppe

    2013-01-01

    ‘Gravity, a Geometrical Course’ presents general relativity (GR) in a systematic and exhaustive way, covering three aspects that are homogenized into a single texture: i) the mathematical, geometrical foundations, exposed in a self consistent contemporary formalism, ii) the main physical, astrophysical and cosmological applications,  updated to the issues of contemporary research and observations, with glimpses on supergravity and superstring theory, iii) the historical development of scientific ideas underlying both the birth of general relativity and its subsequent evolution. The book is divided in two volumes.   Volume One is dedicated to the development of the theory and basic physical applications. It guides the reader from the foundation of special relativity to Einstein field equations, illustrating some basic applications in astrophysics. A detailed  account  of the historical and conceptual development of the theory is combined with the presentation of its mathematical foundations.  Differe...

  10. Geometric theory of information

    CERN Document Server

    2014-01-01

    This book brings together geometric tools and their applications for Information analysis. It collects current and many uses of in the interdisciplinary fields of Information Geometry Manifolds in Advanced Signal, Image & Video Processing, Complex Data Modeling and Analysis, Information Ranking and Retrieval, Coding, Cognitive Systems, Optimal Control, Statistics on Manifolds, Machine Learning, Speech/sound recognition, and natural language treatment which are also substantially relevant for the industry.

  11. Geometrically Consistent Mesh Modification

    KAUST Repository

    Bonito, A.

    2010-01-01

    A new paradigm of adaptivity is to execute refinement, coarsening, and smoothing of meshes on manifolds with incomplete information about their geometry and yet preserve position and curvature accuracy. We refer to this collectively as geometrically consistent (GC) mesh modification. We discuss the concept of discrete GC, show the failure of naive approaches, and propose and analyze a simple algorithm that is GC and accuracy preserving. © 2010 Society for Industrial and Applied Mathematics.

  12. Geometric measure theory

    CERN Document Server

    Waerden, B

    1996-01-01

    From the reviews: "... Federer's timely and beautiful book indeed fills the need for a comprehensive treatise on geometric measure theory, and his detailed exposition leads from the foundations of the theory to the most recent discoveries. ... The author writes with a distinctive style which is both natural and powerfully economical in treating a complicated subject. This book is a major treatise in mathematics and is essential in the working library of the modern analyst." Bulletin of the London Mathematical Society.

  13. Geometric diffusion of quantum trajectories

    Science.gov (United States)

    Yang, Fan; Liu, Ren-Bao

    2015-07-01

    A quantum object can acquire a geometric phase (such as Berry phases and Aharonov-Bohm phases) when evolving along a path in a parameter space with non-trivial gauge structures. Inherent to quantum evolutions of wavepackets, quantum diffusion occurs along quantum trajectories. Here we show that quantum diffusion can also be geometric as characterized by the imaginary part of a geometric phase. The geometric quantum diffusion results from interference between different instantaneous eigenstate pathways which have different geometric phases during the adiabatic evolution. As a specific example, we study the quantum trajectories of optically excited electron-hole pairs in time-reversal symmetric insulators, driven by an elliptically polarized terahertz field. The imaginary geometric phase manifests itself as elliptical polarization in the terahertz sideband generation. The geometric quantum diffusion adds a new dimension to geometric phases and may have applications in many fields of physics, e.g., transport in topological insulators and novel electro-optical effects.

  14. Complex femur fractures in children: treatment with external fixation.

    Science.gov (United States)

    Kirschenbaum, D; Albert, M C; Robertson, W W; Davidson, R S

    1990-01-01

    External fixation was used to treat complex femur fractures in 10 children. These injuries were associated with head trauma, cerebral palsy, epidermolysis bullosa, open wounds, and failed casting. The duration of external fixation averaged 8 weeks, and the mean follow-up was 5 years 8 months. At follow-up, one patient had 2.6 cm of residual shortening, and two had overgrowth. Complications included one refracture. Three children developed superficial pin site drainage. Although most femur fractures can be treated with traction or casting, external fixation may simplify overall care in children with multiple injuries and is effective in controlling unacceptable femoral shortening and angulation.

  15. Validation of a parametric finite element human femur model.

    Science.gov (United States)

    Klein, Katelyn F; Hu, Jingwen; Reed, Matthew P; Schneider, Lawrence W; Rupp, Jonathan D

    2017-05-19

    Finite element (FE) models with geometry and material properties that are parametric with subject descriptors, such as age and body shape/size, are being developed to incorporate population variability into crash simulations. However, the validation methods currently being used with these parametric models do not assess whether model predictions are reasonable in the space over which the model is intended to be used. This study presents a parametric model of the femur and applies a unique validation paradigm to this parametric femur model that characterizes whether model predictions reproduce experimentally observed trends. FE models of male and female femurs with geometries that are parametric with age, femur length, and body mass index (BMI) were developed based on existing statistical models that predict femur geometry. These parametric FE femur models were validated by comparing responses from combined loading tests of femoral shafts to simulation results from FE models of the corresponding femoral shafts whose geometry was predicted using the associated age, femur length, and BMI. The effects of subject variables on model responses were also compared with trends in the experimental data set by fitting similarly parameterized statistical models to both the results of the experimental data and the corresponding FE model results and then comparing fitted model coefficients for the experimental and predicted data sets. The average error in impact force at experimental failure for the parametric models was 5%. The coefficients of a statistical model fit to simulation data were within one standard error of the coefficients of a similarly parameterized model of the experimental data except for the age parameter, likely because material properties used in simulations were not varied with specimen age. In simulations to explore the effects of femur length, BMI, and age on impact response, only BMI significantly affected response for both men and women, with increasing

  16. The Safe Zone for External Fixator Pins in the Femur

    Science.gov (United States)

    2012-11-01

    anatomy to avoid inad- vertent neurovascular injury and intra-articular pin penetra- tion.7,8 Pins placed into the shaft of the femur can be in a lateral...trochanter (LT), perpendicular to the femoral shaft. The final step involved palpation of the superior border of the patella, which was marked. Using a...with SAS 9.1 (Cary, NC). RESULTS Description of Nerve Anatomy The first branch crossed the femur at an average distance from the ASIS of 107 ± 22 mm

  17. Transverse Stress Fracture of the Proximal Patella: A Case Report.

    Science.gov (United States)

    Atsumi, Satoru; Arai, Yuji; Kato, Ko; Nishimura, Akinobu; Nakazora, Shigeto; Nakagawa, Shuji; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Sudo, Akihiro; Kubo, Toshikazu

    2016-02-01

    Among stress fractures associated with sports activities, patellar stress fracture is rare. Regarding patella stress fractures, so far only distal transverse or lateral longitudinal fractures have been reported, but there are no reports of transverse fractures occurring in the proximal patella. We describe an extremely rare case of transverse stress fracture of proximal patella in a 9-year-old athlete.A 9-year old boy, who participated in sports (sprints and Kendo) presented with left knee pain without any external injury. In plain radiographs, a fracture line was observed in the proximal 1/3 of the left patella, and a patella stress fracture was diagnosed. For treatment, because 7 months of conservative therapy showed no improvement, internal fixation was carried out using Acutrak screws, and bone union was thus achieved. Three months after the operation, he was able to return to his previous level of athletic sports activity.Regarding the mechanism of onset, it is believed that the causes are longitudinal traction force and patellofemoral contact pressure. On the other hand, the contact region of the patella with the femur changes with the flexion angle of the knee. In the current case, the fracture occurred at a site where the patella was in contact with the femur at a flexion angle of >90°, so it is believed that it occurred as a clinical condition from being subjected to repeated longitudinal traction force and patellofemoral contact pressure at a flexion angle of >90°, during the sports activities of sprints and Kendo. The nonunion of the transverse stress fracture of his proximal patella was successfully treated with internal fixation using Acutrak screws.

  18. Current concepts in pediatric femur fracture treatment.

    Science.gov (United States)

    Kanlic, Enes; Cruz, Miguel

    2007-12-01

    Femoral neck fractures require urgent evacuation of intracapsular hematoma, anatomic reduction, and secure fixation with screws and cast immobilization. Extracapsular trochanteric and subtrochanteric fractures are best treated by fixed angle devices (locked plates or dynamic screw and side plate). "Length stable" low energy shaft fractures with minimal displacement or nails. Bridge plating will provide better stability in complex fractures. Children > 12 years have less risk of vascular disturbance to the proximal physis, and should have lateral transtrochanateric entry locked rigid nails. Fractures with severe soft tissue injuries could be temporized with external fixation. Distal physis and epiphyseal injuries require anatomical reduction and smooth wires and/or screw fixation (placed in such a way as to minimize further damage to the physis) and need to be augmented with a brace. Leg-length discrepancy is not a significant clinical problem in operatively treated patients. We recommend hardware removal after complete fracture healing, usually in 6 to 12 months. Implants left in the growing child could become buried deep inside of the bone, or cause "periprosthetic" fractures and/or eventually impede adult reconstruction. Minimal risks are reported for hardware removal in healthy patients with healed fractures (4 cortices bridged).

  19. Geometric Algebra Computing

    CERN Document Server

    Corrochano, Eduardo Bayro

    2010-01-01

    This book presents contributions from a global selection of experts in the field. This useful text offers new insights and solutions for the development of theorems, algorithms and advanced methods for real-time applications across a range of disciplines. Written in an accessible style, the discussion of all applications is enhanced by the inclusion of numerous examples, figures and experimental analysis. Features: provides a thorough discussion of several tasks for image processing, pattern recognition, computer vision, robotics and computer graphics using the geometric algebra framework; int

  20. Geometric phases in physics

    CERN Document Server

    Shapere, Alfred D

    1989-01-01

    During the last few years, considerable interest has been focused on the phase that waves accumulate when the equations governing the waves vary slowly. The recent flurry of activity was set off by a paper by Michael Berry, where it was found that the adiabatic evolution of energy eigenfunctions in quantum mechanics contains a phase of geometric origin (now known as 'Berry's phase') in addition to the usual dynamical phase derived from Schrödinger's equation. This observation, though basically elementary, seems to be quite profound. Phases with similar mathematical origins have been identified

  1. Geometrizing adiabatic quantum computation

    Science.gov (United States)

    Rezakhani, Ali; Kuo, Wan-Jung; Hamma, Alioscia; Lidar, Daniel; Zanardi, Paolo

    2010-03-01

    A time-optimal approach to adiabatic quantum computation (AQC) is formulated. The corresponding natural Riemannian metric is also derived, through which AQC can be understood as the problem of finding a geodesic on the manifold of control parameters. We demonstrate this geometrization through some examples, where we show that it leads to improved performance of AQC, and sheds light on the roles of entanglement and curvature of the control manifold in algorithmic performance. The underlying connection with quantum phase transitions is also explored.

  2. Evaluation of vertebral hidden fractures in patients with proximal femoral fractures

    Directory of Open Access Journals (Sweden)

    André Luís Sebben

    2014-12-01

    Full Text Available Objective: To evaluate the Spine Deformity Index (SDI and serum levels of vitamin D in patients surgically treated for proximal femur fracture and its relationship with osteoporosis. Methods: Between August and November 2013, patients older than 50 years-old with surgical fracture of the proximal femur by low-energy trauma underwent radiographic evaluation of the spine and the vitamin D levels, and enquired about diagnoses and previous treatment of osteoporosis. Results: Sixty-six patients met the inclusion criteria. The mean age was 78 years; the average level of vitamin D was 19 ng/mL. The SDI ranged between zero and 25, with a mean of 8.2. Eighty percent of these patients had never been treated for osteoporosis. Of the patients analyzed, 89.3% had insufficient levels of vitamin D. Of these, 68.1% had also SDI above 5, and only one fifth of them had any treatment for osteoporosis. Statistical significance was found between age and levels of vitamin D as well as age and SDI. Gender was not predictive of the vitamin D levels or the amount of hidden spine fractures. The season of the year had no direct influence on vitamin D levels. Conclusions: Hospitalized patients with surgical fractures of the proximal femur had a higher SDI associated with vitamin D insufficiency, with osteoporosis most often untreated, which results in delayed spinal fractures diagnosis of spinal fractures and increased risk of new fractures.

  3. Functional and oncologic outcome of cemented endoprosthesis for malignant proximal femoral tumors.

    Science.gov (United States)

    Houdek, Matthew T; Watts, Chad D; Wyles, Cody C; Rose, Peter S; Taunton, Michael J; Sim, Franklin H

    2016-09-01

    Cemented endoprosthetic replacement is an option for reconstruction of the proximal femur to achieve limb salvage. Existing outcome studies combine benign and malignant conditions, or group endoprostheses from multiple areas into one cohort. We sought to examine a series of endoprosthetic replacements of the proximal femur for a malignant process. We reviewed 204 patients who underwent an endoprosthesis for a malignant process of the proximal femur with at least 2-year follow-up. Mean age was 59 years, with 55% being male. The most common pathology was metastatic disease (n = 120, 59%). Mean follow-up was 7 years (2-22 years). Mean time to death was 2 years (range 2 weeks-18 years). A bipolar component was used in 93% of patients. 5-year survival was 8% in patients with metastatic disease and 54% for patients with primary disease. Local recurrence and metastatic disease developed in 5 and 19 patients with a primary sarcoma. Following the procedure the mean Harris Hip and Musculoskeletal Tumor Society Scores were 75 and 18. Patients typically succumb to their disease prior to implant failure; however, endoprosthetic replacement provides patients with an acceptable means of functional recovery with an acceptable complication profile. J. Surg. Oncol. 2016;114:501-506. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Bone mineral density changes of lumbar spine and femur in osteoporotic patient treated with bisphosphonates and beta-hydroxy-beta-methylbutyrate (HMB): Case report.

    Science.gov (United States)

    Tatara, Marcin R; Krupski, Witold; Majer-Dziedzic, Barbara

    2017-10-01

    Currently available approaches to osteoporosis treatment include application of antiresorptive and anabolic agents influencing bone tissue metabolism. The aim of the study was to present bone mineral density (BMD) changes of lumbar spine in osteoporotic patient treated with bisphosphonates such as ibandronic acid and pamidronic acid, and beta-hydroxy-beta-methylbutyrate (HMB). BMD and volumetric BMD (vBMD) of lumbar spine were measured during the 6 year observation period with the use of dual-energy X-ray absorptiometry (DEXA) and quantitative computed tomography (QCT). The described case report of osteoporotic patient with family history of severe osteoporosis has shown site-dependent response of bone tissue to antiosteoporotic treatment with bisphosphonates. Twenty-five-month treatment with ibandronic acid improved proximal femur BMD with relatively poor effects on lumbar spine BMD. Over 15-month therapy with pamidronic acid was effective to improve lumbar spine BMD, while in the proximal femur the treatment was not effective. A total of 61-week long oral administration with calcium salt of HMB improved vBMD of lumbar spine in the trabecular and cortical bone compartments when monitored by QCT. Positive effects of nearly 2.5 year HMB treatment on BMD of lumbar spine and femur in the patient were also confirmed using DEXA method. The results obtained indicate that HMB may be applied for the effective treatment of osteoporosis in humans. Further studies on wider human population are recommended to evaluate mechanisms influencing bone tissue metabolism by HMB.

  5. Capacitive proximity sensor

    Science.gov (United States)

    Kronberg, James W.

    1994-01-01

    A proximity sensor based on a closed field circuit. The circuit comprises a ring oscillator using a symmetrical array of plates that creates an oscillating displacement current. The displacement current varies as a function of the proximity of objects to the plate array. Preferably the plates are in the form of a group of three pair of symmetric plates having a common center, arranged in a hexagonal pattern with opposing plates linked as a pair. The sensor produces logic level pulses suitable for interfacing with a computer or process controller. The proximity sensor can be incorporated into a load cell, a differential pressure gauge, or a device for measuring the consistency of a characteristic of a material where a variation in the consistency causes the dielectric constant of the material to change.

  6. Neighborhoods and manageable proximity

    Directory of Open Access Journals (Sweden)

    Stavros Stavrides

    2011-08-01

    Full Text Available The theatricality of urban encounters is above all a theatricality of distances which allow for the encounter. The absolute “strangeness” of the crowd (Simmel 1997: 74 expressed, in its purest form, in the absolute proximity of a crowded subway train, does not generally allow for any movements of approach, but only for nervous hostile reactions and submissive hypnotic gestures. Neither forced intersections in the course of pedestrians or vehicles, nor the instantaneous crossing of distances by the technology of live broadcasting and remote control give birth to places of encounter. In the forced proximity of the metropolitan crowd which haunted the city of the 19th and 20th century, as well as in the forced proximity of the tele-presence which haunts the dystopic prospect of the future “omnipolis” (Virilio 1997: 74, the necessary distance, which is the stage of an encounter between different instances of otherness, is dissipated.

  7. The effect of collar on aseptic loosening and proximal femoral bone resorption in hybrid total hip arthroplasty.

    Science.gov (United States)

    Caglar, Omur; Atilla, Bulent; Tokgozoglu, Mazhar; Alpaslan, Mumtaz

    2008-03-01

    This study compared proximal femoral bone resorption in hybrid total hip arthroplasty cases that had poor or good contact between the collar and proximal medial femoral neck. A total of 94 patients (102 hips) comprised the study group. Mean patient age was 52 years, and mean follow-up was 4.86 years. Bone resorption of the proximal femur was evaluated with immediate postoperative and follow-up anteroposterior and lateral radiographs. Statistical analysis using the Mann-Whitney test showed no significant difference between the groups that had good or poor contact. The collar did not prevent calcar resorption even when ideal contact was achieved.

  8. Treatment of femur shaft fractures using Perkins' traction at Addis ...

    African Journals Online (AJOL)

    60 (88.2%) were males and only 8 (11.8%) were females making the fracture over eight times frequent ... good results with their use of a single rope suspension .... of causes of all adult femur shaft fractures presented to BLH, radiology department. Cause. Frequency. (%). RTA. 202. 47.9. Fall. 126. 29.9. Machine. 28. 6.6.

  9. Bilateral recon nailing of comminuted fracture femur in a severely ...

    African Journals Online (AJOL)

    The patient was mobilized from bed to chair post-operatively. After 4 weeks from the last surgery he was gradually mobilized full weight bearing with a walker. At 4 months follow-up he was walking full weight bearing without support. Recon nails can be employed successfully to treat complex fractures of the femur shaft.

  10. Gunshot fractures of tibia and femur - excellent results with reamed ...

    African Journals Online (AJOL)

    East African Medical Journal ... Objective: To document the outcome of treatment of femur and tibia diaphyseal fractures due to gunshot injury grafted with reamed bone marrow and immobilised with Surgical Implant ... Mean outcome measure: Clinical and radiological evidences of healing of the fracture at six weeks.

  11. Small stem total hip arthroplasty in hypoplasia of the femur

    NARCIS (Netherlands)

    de Man, F. Harald R.; Haverkamp, Daniel; van der Vis, Harm M.; Besselaar, Philip P.; Marti, René K.

    2008-01-01

    Total hip arthroplasty in hypoplastic femurs is technically difficult and the incidence of complications and aseptic loosening is relatively high. Cemented, uncemented, off-the-shelf, and custom-made stems all have been advocated in these cases. From 1978 to 1997, we performed 86 total hip

  12. Subtrochanteric and Distal Femur Fractures in a Patient with ...

    African Journals Online (AJOL)

    This study aims to describe a rare and challenging case of a patient who presented ipsilateral subtrochanteric and distal femur fractures due to low‑energy trauma. The peculiarity of this case is the presence of femoral shaft fracture malunion and knee disarticulation in the same limb resulting from an accident suffered 30 ...

  13. management of bilateral fracture femur with implant failure

    African Journals Online (AJOL)

    . In summary, patients with bilateral fractures of the femur are difficult to treat. These are factures where one must consider strongly the use of operative method of fixation. Further, one needs to choose a means of definite fixation which will ...

  14. Experimental investigation of bone remodelling using composite femurs.

    NARCIS (Netherlands)

    Waide, V.; Cristofolini, L.; Stolk, J.; Verdonschot, N.J.J.; Toni, A.

    2003-01-01

    OBJECTIVE: To determine the load transfer patterns of femurs in the intact, immediate post-operative and long-term (remodelled) post-operative implanted conditions for Lubinus SPII and Muller-Curved cemented hip prostheses, and to examine to what extent remodelling may influence the long-term

  15. Operative treatment of a unilateral bicondylar fracture of the femur

    NARCIS (Netherlands)

    Zeebregts, CJAM; Zimmerman, KW; ten Duis, HJ

    A case of isolated tangential fracture of the dorsal part of both condyles of the femur (bicondylar Hoffa fracture) is described. After open reduction, four lag screws were introduced through the fractured condyles to fur the fragments. A plaster cast was applied for a period of four weeks. Full

  16. Poor relation between biomechanical and clinical studies for the proximal femoral locking compression plate

    DEFF Research Database (Denmark)

    Viberg, Bjarke; Voergård Rasmussen, Katrine Marie; Overgaard, Søren

    2017-01-01

    or higher failure loads for femoral neck fracture, the clinical results were far worse, with a 37% complication rate. There were no biomechanical studies on pertrochanteric fractures. Biomechanical studies on subtrochanteric fractures showed that PF-LCP had a lower failure load than with proximal femoral......Background and purpose — The proximal femur locking compression plate (PF-LCP) is a new concept in the treatment of hip fractures. When releasing new implants onto the market, biomechanical studies are conducted to evaluate performance of the implant. We investigated the relation between...

  17. Atrofia muscular proximal familiar

    Directory of Open Access Journals (Sweden)

    José Antonio Levy

    1962-09-01

    Full Text Available Os autores relatam dois casos de atrofia muscular proximal familiar, moléstia caracterizada por déficit motor e atrofias musculares de distribuição proximal, secundárias a lesão de neurônios periféricos. Assim, como em outros casos descritos na literatura, foi feito inicialmente o diagnóstico de distrofia muscular progressiva. O diagnóstico correto foi conseguido com auxílio da eletromiografia e da biopsia muscular.

  18. Prevalence of abuse among young children with femur fractures: a systematic review

    OpenAIRE

    Wood, Joanne N.; Fakeye, Oludolapo; Mondestin, Valerie; Rubin, David M.; Localio, Russell; Feudtner, Chris

    2014-01-01

    Background Clinical factors that affect the likelihood of abuse in children with femur fractures have not been well elucidated. Consequently, specifying which children with femur fractures warrant an abuse evaluation is difficult. Therefore the purpose of this study is to estimate the proportion of femur fractures in young children attributable to abuse and to identify demographic, injury and presentation characteristics that affect the probability that femur fractures are secondary to abuse....

  19. The Odocoileus virginianus Femur: Mechanical Behavior and Morphology.

    Directory of Open Access Journals (Sweden)

    Mark J Hedgeland

    Full Text Available Biomechanical research relies heavily on laboratory evaluation and testing with osseous animal structures. While many femora models are currently in use, including those of the European red deer (Cervus elaphus, the Odocoileus virginianus femur remains undocumented, despite its regional abundance in North America. The objective of this study was to compare biomechanical and morphological properties of the Odocoileus virginianus femur with those of the human and commonly used animal models. Sixteen pairs of fresh-frozen cervine femora (10 male, 6 female, aged 2.1 ± 0.9 years were used for this study. Axial and torsional stiffnesses (whole bone were calculated following compression and torsion to failure tests (at rates of 0.1 mm/sec and 0.2°/sec. Lengths, angles, femoral head diameter and position, periosteal and endosteal diaphyseal dimensions, and condylar dimensions were measured. The results show that the cervine femur is closer in length, axial and torsional stiffness, torsional strength, and overall morphology to the human femur than many other commonly used animal femora models; additional morphological measurements are comparable to many other species' femora. The distal bicondylar width of 59.3mm suggests that cervine femora may be excellent models for use in total knee replacement simulations. Furthermore, the cervine femoral head is more ovoid than other commonly-used models for hip research, making it a more suitable model for studies of hip implants. Thus, with further, more application-specific investigations, the cervine femur could be a suitable model for biomechanical research, including the study of ballistic injuries and orthopaedic device development.

  20. Is there any relation between distal parameters of the femur and its height and width?

    Science.gov (United States)

    Yazar, Fatih; Imre, Nurcan; Battal, Bilal; Bilgic, Serkan; Tayfun, Cem

    2012-03-01

    The purpose of this study was to reveal the association whether the distal morphometry of femur had a relation with femur height or width. Sixty-six adult (35 right and 31 left) dry femurs from Caucasians were used in this study. Computed tomography (CT) imaging was applied to obtain measurement values of the femur. Femur height (413.29 ± 28.40 mm) and width (29.86 ± 2.72 mm) were all checked one by one to determine the correlation with the parameters obtained. Both values exposed high rates of correlation with height (26 ± 2.34 mm) and width (20.85 ± 2.76 mm) of femur notch; also, measures of epicondylar, bicondylar and condylar diameters of femur were obtained. Measures were checked if there was a correlation with femur height and width. Differences displayed in distal morphometry of femur according to race and sex are due to other morphometric measures of femur rather than race and sex. We believe that displaying the high rates of correlation of distal morphometry of femur with femur height and width will be the factor which determines the selection and production of prosthesis among the long or short individuals of folks.

  1. Determination of femur stature ratio of the Ijaw and Ikwerre ethnic ...

    African Journals Online (AJOL)

    Determination of femur stature ratio of the Ijaw and Ikwerre ethnic groups in Nigeria. H.B. Fawehinmi, T.R. Ogoun, S.C. Okoseimiema. Abstract. The average Femur stature ratio of the Ijaw and the Ikwerre ethnic groups in Nigeria was studied. A formula for identification of the height of these ethnic groups from their femur ...

  2. Chronic skeletal unloading of the rat femur: mechanisms and functional consequences of vascular remodeling.

    Science.gov (United States)

    Stabley, John N; Prisby, Rhonda D; Behnke, Bradley J; Delp, Michael D

    2013-12-01

    Chronic skeletal unloading diminishes hindlimb bone blood flow. The purpose of the present investigation was to determine 1) whether 7 and 14days of skeletal unloading alter femoral bone and marrow blood flow and vascular resistance during reloading, and 2) whether putative changes in bone perfusion are associated with a gross structural remodeling of the principal nutrient artery (PNA) of the femur. Six-month old male Sprague-Dawley rats were assigned to 7-d or 14-d hindlimb unloading (HU) or weight-bearing control groups. Bone perfusion was measured following 10min of standing (reloading) following the unloading treatment. Histomorphometry was used to determine PNA media wall thickness and maximal diameter. Bone blood flow, arterial pressure and PNA structural characteristics were used to calculate arterial shear stress and circumferential wall stress. During reloading, femoral perfusion was lower in the distal metaphyseal region of 7-d HU rats, and in the proximal and distal metaphyses, diaphysis and diaphyseal marrow of 14-d HU animals relative to that in control rats. Vascular resistance was also higher in all regions of the femur in 14-d HU rats during reloading relative to control animals. Intraluminal diameter of PNAs from 14-d HU rats (138±5μm) was smaller than that of control PNAs (162±6μm), and medial wall thickness was thinner in PNAs from 14-d HU (14.3±0.6μm) versus that of control (18.0±0.8μm) rats. Decreases in both shear stress and circumferential stress occurred in the PNA with HU that later returned to control levels with the reductions in PNA maximal diameter and wall thickness, respectively. The results demonstrate that chronic skeletal unloading attenuates the ability to increase blood flow and nutrient delivery to bone and marrow with immediate acute reloading due, in part, to a remodeling of the bone resistance vasculature. © 2013.

  3. Biomechanics and structural adaptations of the rat femur after hindlimb suspension and treadmill running

    Directory of Open Access Journals (Sweden)

    M.M. Shimano

    2009-04-01

    Full Text Available We microscopically and mechanically evaluated the femurs of rats subjected to hindlimb unloading (tail suspension followed by treadmill training. Female Wistar rats were randomly divided into five groups containing 12-14 rats: control I (118 days old, control II (139 days old, suspended (tail suspension for 28 days, suspended-released (released for 21 days after 28 days of suspension, and suspended-trained (trained for 21 days after 28 days of suspension. We measured bone resistance by bending-compression mechanical tests of the entire proximal half of the femur and three-point bending tests of diaphyseal cortical bone. We determined bone microstructure by tetracycline labeling of trabecular and cortical bone. We found that tail suspension weakened bone (ultimate load = 86.3 ± 13.5 N, tenacity modulus = 0.027 ± 0.011 MPa·m vs ultimate load = 101.5 ± 10.5 N, tenacity modulus = 0.019 ± 0.006 MPa·m in control I animals. The tenacity modulus for suspended and released animals was 0.023 ± 0.010 MPa·m vs 0.046 ± 0.018 MPa·m for trained animals and 0.035 ± 0.010 MPa·m for control animals. These data indicate that normal activity and training resulted in recovered bone resistance, but suspended-released rats presented femoral head flattening and earlier closure of the growth plate. Microscopically, we found that suspension inhibited new bone subperiosteal and endosteal formation. The bone disuse atrophy secondary to hypoactivity in rats can be reversed by an early regime of exercising, which is more advantageous than ordinary cage activities alone.

  4. A method for the estimation of femoral bone mineral density from variables of ultrasound transmission through the human femur.

    Science.gov (United States)

    Barkmann, R; Laugier, P; Moser, U; Dencks, S; Padilla, F; Haiat, G; Heller, M; Glüer, C-C

    2007-01-01

    Quantitative ultrasound (QUS) measurements at peripheral sites can be used to estimate osteoporotic fracture risk. However, measurements at these sites are less suitable to predict bone mineral density (BMD) or fracture risk at the central skeleton. We investigated whether direct QUS measurements at the femur would allow to estimate dual X-ray absorptiometry (DXA) BMD of the total proximal femur with errors comparable to established DXA accuracy errors. Two independent sets of femora were measured in Kiel (6 f, 4 m, age: 55-90) and Paris (19 f, 20 m age: 45-95) using different benchtop systems in the two laboratories. The femora were scanned in transverse transmission mode using focused US transducers of 500 kHz center frequency. The QUS values were averaged over a region similar to the total hip region of dual X-ray absorptiometry (DXA) measurements. BMD was measured using DXA. SOS and BMD correlated significantly (p<0.0001) in both data sets (R2=0.81-0.93). Correlations between BUA and BMD were also significant at p<0.001, but correlation coefficients were lower (R2=0.61-0.75). Residual errors for the estimation of BMD were 8%-10% for SOS as predictor, and 14%-16% for BUA as predictor. The residual error of 8 to 10% for the estimation of BMD from SOS is comparable to variabilities among different DXA femur subregions and accuracy errors of femoral DXA measurements caused by the impact of soft tissue. It is substantially smaller than the errors of 13% for the estimation of total femur BMD from spine BMD, 14% for the estimation of total femur BMD from calcaneus SOS or 16% for the estimation of ash weight from DXA. The results of the study show that SOS is able to predict total BMD with adequate accuracy. If femoral BMD could be obtained in vivo with comparable accuracy, femoral QUS would be suited for the assessment of bone status at one of the main osteoporotic fracture sites.

  5. [Experimental proximal carpectomy. Biodynamics].

    Science.gov (United States)

    Kuhlmann, J N

    1992-01-01

    Proximal carpectomy was performed in 10 fresh cadavre wrists. Dynamic x-rays were taken and the forces necessary to obtain different movements before and after the operation were measured. Comparison of these parameters clearly defines the advantages and limitations of carpectomy and indicates the reasons.

  6. Proximate Analysis of Coal

    Science.gov (United States)

    Donahue, Craig J.; Rais, Elizabeth A.

    2009-01-01

    This lab experiment illustrates the use of thermogravimetric analysis (TGA) to perform proximate analysis on a series of coal samples of different rank. Peat and coke are also examined. A total of four exercises are described. These are dry exercises as students interpret previously recorded scans. The weight percent moisture, volatile matter,…

  7. Proximal Tibial Bone Graft

    Science.gov (United States)

    ... the Big Toe Ailments of the Smaller Toes Diabetic Foot Treatments Currently selected Injections and other Procedures Treatments ... from which the bone was taken if the foot/ankle surgeries done at the same time allow for it. ... problems after a PTBG include infection, fracture of the proximal tibia and pain related ...

  8. The Relationship Between Fractures and DXA Measures of BMD in the Distal Femur of Children and Adolescents With Cerebral Palsy or Muscular Dystrophy

    Science.gov (United States)

    Henderson, Richard C; Berglund, Lisa M; May, Ryan; Zemel, Babette S; Grossberg, Richard I; Johnson, Julie; Plotkin, Horacio; Stevenson, Richard D; Szalay, Elizabeth; Wong, Brenda; Kecskemethy, Heidi H; Harcke, H Theodore

    2010-01-01

    Children with limited or no ability to ambulate frequently sustain fragility fractures. Joint contractures, scoliosis, hip dysplasia, and metallic implants often prevent reliable measures of bone mineral density (BMD) in the proximal femur and lumbar spine, where BMD is commonly measured. Further, the relevance of lumbar spine BMD to fracture risk in this population is questionable. In an effort to obtain bone density measures that are both technically feasible and clinically relevant, a technique was developed involving dual-energy X-ray absorptiometry (DXA) measures of the distal femur projected in the lateral plane. The purpose of this study is to test the hypothesis that these new measures of BMD correlate with fractures in children with limited or no ability to ambulate. The relationship between distal femur BMD Z-scores and fracture history was assessed in a cross-sectional study of 619 children aged 6 to 18 years with muscular dystrophy or moderate to severe cerebral palsy compiled from eight centers. There was a strong correlation between fracture history and BMD Z-scores in the distal femur; 35% to 42% of those with BMD Z-scores less than −5 had fractured compared with 13% to 15% of those with BMD Z-scores greater than −1. Risk ratios were 1.06 to 1.15 (95% confidence interval 1.04–1.22), meaning a 6% to 15% increased risk of fracture with each 1.0 decrease in BMD Z-score. In clinical practice, DXA measure of BMD in the distal femur is the technique of choice for the assessment of children with impaired mobility. © 2010 American Society for Bone and Mineral Research PMID:19821773

  9. Geometric phase around exceptional points

    OpenAIRE

    Mailybaev, Alexei; Kirillov, Oleg; Seyranian, Alexander,

    2005-01-01

    A wave function picks up, in addition to the dynamic phase, the geometric (Berry) phase when traversing adiabatically a closed cycle in parameter space. We develop a general multidimensional theory of the geometric phase for (double) cycles around exceptional degeneracies in non-Hermitian Hamiltonians. We show that the geometric phase is exactly $\\pi$ for symmetric complex Hamiltonians of arbitrary dimension and for nonsymmetric non-Hermitian Hamiltonians of dimension 2. For nonsymmetric non-...

  10. EXPERIMENTAL APPROVAL OF COMBINED FIXATION FOR FEMUR LENGTHENING

    Directory of Open Access Journals (Sweden)

    M. A. Stepanov

    2017-01-01

    Full Text Available Elimination of congenital shortening of lower limb still remains a complex and unsolved orthopaedic task which requires an improved fixation technique as well as adjusted tactics of treatment and rehabilitation procedures.Purpose of the study — experimental approval of femur lengthening technique by external fixation with Ilizarov apparatus and internal fixation by plate.Materials and methods. Femur lengthening was performed in 6 mongrel dogs. Average animal age was 1,5±0,3 years, average weight — 20±5 kg, femur length — 22±2 sm. External apparatus with two supports and a titanium plate of an original design were applied under general anesthesia on the right femur of animals. Lengthening was performed manually at a rate of1 mm per day in 4 stages at a distance of 10% from initial segment length. External apparatus was removed on the last day of distraction after locking the plate. X-ray examination was done on the day of surgery, in 7, 14 and 25 days from the onset of distraction as well as in 14, 30, 60 and 90 days after completion of distraction and removal of external apparatus. Three animals were taken out of experiment in 30 days of fixation, remaining three animals — in 90 days. After euthanasia the authors performed autopsy of the organic femur complex and tissues contacting the plate.Results. The use of operated limb was not restricted during the whole distraction period. The authors observed first roentgenological signs of distraction osteogenesis on 7th day of lengthening. By the end of distraction period, at 25th day, shadows of regenerates demonstrated longitudinal striated structures in all cases. Median lucency area of 1–5 mm was located diagonally and across the regenerate or was intermittent. In 60 days of fixation X-rays demonstrated homogeneous regenerate. External fixation index was 13,9±1,5 days/sm (p≤0,05. The authors observed no cases of implants fracture or deformity during the experiment

  11. Three-Dimensional Analysis of the Curvature of the Femoral Canal in 426 Chinese Femurs

    Science.gov (United States)

    Su, Xiu-Yun; Zhao, Zhe; Zhao, Jing-Xin; Zhang, Li-Cheng; Long, An-Hua; Zhang, Li-Hai; Tang, Pei-Fu

    2015-01-01

    Purpose. The human femur has long been considered to have an anatomical anterior curvature in the sagittal plane. We established a new method to evaluate the femoral curvature in three-dimensional (3D) space and reveal its influencing factors in Chinese population. Methods. 3D models of 426 femurs and the medullary canal were constructed using Mimics software. We standardized the positions of all femurs using 3ds Max software. After measuring the anatomical parameters, including the radius of femoral curvature (RFC) and banking angle, of the femurs using the established femur-specific coordinate system, we analyzed and determined the relationships between the anatomical parameters of the femur and the general characteristics of the population. Results. Pearson's correlation analyses showed that there were positive correlations between the RFC and height (r = 0.339, p femur was significantly larger in female than in male. PMID:26640785

  12. Proximal femoral fractures

    DEFF Research Database (Denmark)

    Palm, Henrik; Teixidor, Jordi

    2015-01-01

    -displaced femoral neck fractures and prosthesis for displaced among the elderly; and sliding hip screw for stabile- and intramedullary nails for unstable- and sub-trochanteric fractures) but they are based on a variety of criteria and definitions - and often leave wide space for the individual surgeons' subjective...... guidelines for hip fracture surgery and discuss a method for future pathway/guideline implementation and evaluation. METHODS: By a PubMed search in March 2015 six studies of surgical treatment pathways covering all types of proximal femoral fractures with publication after 1995 were identified. Also we...... searched the homepages of the national heath authorities and national orthopedic societies in West Europe and found 11 national or regional (in case of no national) guidelines including any type of proximal femoral fracture surgery. RESULTS: Pathway consensus is outspread (internal fixation for un...

  13. Proximal humeral fractures

    OpenAIRE

    Mauro, Craig S.

    2011-01-01

    Proximal humeral fractures may present with many different configurations in patients with varying co-morbities and expectations. As a result, the treating physician must understand the fracture pattern, the quality of the bone, other patient-related factors, and the expanding range of reconstructive options to achieve the best functional outcome and to minimize complications. Current treatment options range from non-operative treatment with physical therapy to fracture fixation using percuta...

  14. Intraoperative Periprosthetic Femur Fracture: A Biomechanical Analysis of Cerclage Fixation.

    Science.gov (United States)

    Frisch, Nicholas B; Charters, Michael A; Sikora-Klak, Jakub; Banglmaier, Richard F; Oravec, Daniel J; Silverton, Craig D

    2015-08-01

    Intraoperative periprosthetic femur fracture is a known complication of total hip arthroplasty (THA) and a variety of cerclage systems are available to manage these fractures. The purpose of this study was to examine the in situ biomechanical response of cerclage systems for fixation of periprosthetic femur fractures that occur during cementless THA. We compared cobalt chrome (CoCr) cables, synthetic cables, monofilament wires and hose clamps under axial compressive and torsional loading. Metallic constructs with a positive locking system performed the best, supporting the highest loads with minimal implant subsidence (both axial and angular) after loading. Overall, the CoCr cable and hose clamp had the highest construct stiffness and least reduction in stiffness with increased loading. They were not demonstrably different from each other. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Management von Kombinationsfrakturen des Femurschafts und des proximalen Femurs

    DEFF Research Database (Denmark)

    Schmal, H; Strohm, P C; Mehlhorn, A T

    2008-01-01

    . Also considering the combination of femoral shaft fractures with fractures of the acetabulum and the distal femur (knee), the proportion of chain injuries of the femur was 3.1%. The rate of multiply injured patients in the group of patients with ipsilateral femoral neck and shaft fractures was 64......PURPOSE: The combination of ipsilateral femoral neck and shaft fractures remains a treatment challenge in orthopedic surgery because both fracture types constitute separate entities and require specific treatment concepts. MATERIAL AND METHODS: In a case control study, incidence, treatment...... strategies, and outcomes of this injury were analyzed. All patients with femoral fractures treated between 1 January 2001 and 31 July 2007 at a level I trauma center were included in the study. RESULTS: Twenty-one out of 1,935 patients (1.1%) sustained 22 combined fractures of the femoral neck and shaft...

  16. Temporary hemiepiphysiodesis of the distal medial femur: MPFL in danger.

    Science.gov (United States)

    Bachmann, M; Rutz, E; Brunner, R; Gaston, M S; Hirschmann, M T; Camathias, C

    2014-08-01

    Temporary hemiepiphysiodesis (TH) with plate fixation is a well-accepted and common treatment for correcting leg malalignment in skeletally immature patients. The purpose of this study was to investigate any soft tissue damage caused during TH at the distal medial femur with a plate and two screws. We hypothesized that correct plate placement can affect the integrity of the medial stabilizing structures of the knee, especially the medial patellofemoral ligament (MPFL), the medial collateral ligament (MCL) or result in arthrotomy of the knee joint itself. In eight cadaveric knees of five adult humans a TH was performed with a plate and two cancellous screws at the distal medial femur using a standardized surgical technique. Subsequently the medial capsular and ligamentous structures were systematically exposed and assessed. Capsular and synovial tissue was also inspected for impingement by the plate or screws. In all knees the MPFL was present. In two specimens the MPFL was intact and the plate was lying over the dorsal part of the MPFL close to the MCL. The MPFL was completely cut in two cases in the central part of the ligament. In four cases the MPFL was partially dissected or perforated by a screw and fixed to the femur by the plate. The MCL was intact and not impinged by the implant in any case. In total four of eight knees the capsule was transected or perforated by a screw or by a part of the plate, resulting in intraarticular implant placement. Standard plate placement during TH on the distal medial femur frequently leads to damage to the MPFL, impingement of the MPFL, the capsular and synovial tissues or exposure of the knee joint.

  17. Harmonic and geometric analysis

    CERN Document Server

    Citti, Giovanna; Pérez, Carlos; Sarti, Alessandro; Zhong, Xiao

    2015-01-01

    This book presents an expanded version of four series of lectures delivered by the authors at the CRM. Harmonic analysis, understood in a broad sense, has a very wide interplay with partial differential equations and in particular with the theory of quasiconformal mappings and its applications. Some areas in which real analysis has been extremely influential are PDE's and geometric analysis. Their foundations and subsequent developments made extensive use of the Calderón–Zygmund theory, especially the Lp inequalities for Calderón–Zygmund operators (Beurling transform and Riesz transform, among others) and the theory of Muckenhoupt weights.  The first chapter is an application of harmonic analysis and the Heisenberg group to understanding human vision, while the second and third chapters cover some of the main topics on linear and multilinear harmonic analysis. The last serves as a comprehensive introduction to a deep result from De Giorgi, Moser and Nash on the regularity of elliptic partial differen...

  18. Enhancing geometric reasoning.

    Science.gov (United States)

    Mistretta, R M

    2000-01-01

    Geometry is an important part of the mathematics curriculum. However, students are not demonstrating strong conceptual knowledge of this subject. The research of Van Hiele and Van Hiele-Geldof has focused on the concept of thinking levels in geometry and the role of instruction in raising levels of thinking. This paper describes a field trial of a supplemental geometry unit intended to raise Van Hiele thinking levels in a group of 23 eighth-grade students by having them become more adept at using higher order thinking skills. Sample questions assessing particular Van Hiele thinking levels and attitudes toward geometry, as well as field-tested activities yielding the most positive results, are presented. Educators can benefit from this application of the Van Hiele model of geometric thinking, since the thought processes involved in learning geometry are explained, along with teaching techniques and tools for assessment. By having teachers become more aware of their students' cognitive skills, attitudes, and misconceptions, teaching practices and student achievement can be enhanced.

  19. Noninvasive Femur Bone Volume Estimation Based on X-Ray Attenuation of a Single Radiographic Image and Medical Knowledge

    Science.gov (United States)

    Kiattisin, Supaporn; Chamnongthai, Kosin

    Bone Mineral Density (BMD) is an indicator of osteoporosis that is an increasingly serious disease, particularly for the elderly. To calculate BMD, we need to measure the volume of the femur in a noninvasive way. In this paper, we propose a noninvasive bone volume measurement method using x-ray attenuation on radiography and medical knowledge. The absolute thickness at one reference pixel and the relative thickness at all pixels of the bone in the x-ray image are used to calculate the volume and the BMD. First, the absolute bone thickness of one particular pixel is estimated by the known geometric shape of a specific bone part as medical knowledge. The relative bone thicknesses of all pixels are then calculated by x-ray attenuation of each pixel. Finally, given the absolute bone thickness of the reference pixel, the absolute bone thickness of all pixels is mapped. To evaluate the performance of the proposed method, experiments on 300 subjects were performed. We found that the method provides good estimations of real BMD values of femur bone. Estimates shows a high linear correlation of 0.96 between the volume Bone Mineral Density (vBMD) of CT-SCAN and computed vBMD (all PCT-SCAN.

  20. Predictors of Functional Recovery Following Periprosthetic Distal Femur Fractures.

    Science.gov (United States)

    Ruder, John A; Hart, Gavin P; Kneisl, Jeffrey S; Springer, Bryan D; Karunakar, Madhav A

    2017-05-01

    Treatment options for periprosthetic distal femur fractures include open reduction internal fixation (ORIF) and distal femoral replacement (DFR). The purpose of this study was to evaluate the complications, and functional recovery (ambulatory status, living situation, mortality) in patients undergoing operative treatment (DFR and ORIF) of periprosthetic distal femur fractures. A retrospective review of 58 patients with distal femoral periprosthetic fractures treated with either ORIF or DFR was conducted. Surgical complications, discharge disposition, ambulatory status, living situation at 1 year, and mortality at 1 year were compared between patients treated with ORIF and DFR. Outcomes at 1 year were also compared between patients older and younger than 85 years of age. Fifty-eight patients with a mean age of 80 years (range, 61-95 years) met inclusion criteria. The mean follow-up was 29.5 months (range, 5-81 months). Patients undergoing DFR were significantly older than those who underwent ORIF (83 vs 78, P femur fractures. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Geometric phase and quantum potential

    OpenAIRE

    Dandoloff, R.

    2002-01-01

    We show that the geometric phase of Levy-Leblond arises from a low of parallel transport for wave functions and point out that this phase belongs to a new class of geometric phases due to the presence of a quantum potential.

  2. Geometrical approach to fluid models

    NARCIS (Netherlands)

    Kuvshinov, B. N.; Schep, T. J.

    1997-01-01

    Differential geometry based upon the Cartan calculus of differential forms is applied to investigate invariant properties of equations that describe the motion of continuous media. The main feature of this approach is that physical quantities are treated as geometrical objects. The geometrical

  3. Geometric Modeling for Computer Vision

    Science.gov (United States)

    1974-10-01

    The main contribution of this thesis is the development of a three dimensional geometric modeling system for application to computer vision . In... computer vision geometric models provide a goal for descriptive image analysis, an origin for verification image synthesis, and a context for spatial

  4. {sup 99m}Tc-MDP bone uptake in secondary hyperparathyroidism: comparison among mandible, cranium, radius and femur

    Energy Technology Data Exchange (ETDEWEB)

    Boasquevisque, Edson; Silva, Jorge Wagner Esteves da; Bernardo, Vanessa V. de Albuquerque; Macedo, Sara Mello Santana de; Boasquevisque, Camila S.

    2008-07-01

    Full text: Objective: Evaluating bone involvement in secondary hyperparathyroidism (SHPT) by {sup 99m}Tc-MDP uptake in the mandible, cranium, radius and femur and with data correlation with PTHi serum (Intact Parathyroid Hormone). Materials and Methods: In a prospective study of 54 patients with SHPT due to chronic renal disease and 15 normal individuals (control group), all patients had elevated serum PTHi, concentration and positive {sup 99m}Tc-MDP bone scintigraphy. Bone uptake measurements were carried out drawing regions-of-interest (ROI) on the mandible, posterior cranium, distal radius and proximal femur. Additionally, soft tissue uptake was measured with one region-of-interest on the internal tight soft tissue (BG). The ROI-BG ratio used as the index of normalized bone uptake. Results: The uptake differences from SHPT and control groups mainly for mandible (p = 0,001) and cranium (p = 0,002) were statistically significant, even when the SHPT groups were separated according to serum PTHi levels. There was increased bone uptake with the increased levels of PTHi serum. All of the mandibles of the SHPT patients were abnormal with 33% having focal lesions. Conclusions: The bone uptake in SHPT group was abnormal in all areas evaluated, with high uptake of {sup 99m}Tc-MDP correlated to the increase of PTHi serum concentration. (author)

  5. The potential application of functionally graded material for proximal femoral nail antirotation device.

    Science.gov (United States)

    Gong, He; Wang, Lizhen; Zheng, Dong; Fan, Yubo

    2012-09-01

    Proximal femoral nail antirotation (PFNA) device is an intramedullary nail system designing for the treatment of trochanteric fractures. It is composed of a helical neck blade, a nail and a distal locking bolt. There were some reports of femoral shaft fractures even after the fractures were healed. The stress shielding effects of the PFNA device made of stiff titanium alloy on the bone-remodeling behavior of the host femur and the uneven distribution of interface shear stress may contribute to this complication. Recently, a new class of composite called functionally graded material (FGM) was developed, that consisted a gradual pattern of material composition and/or microstructures, and was introduced in dental implant and cementless hip stem. Accordingly, in this paper, we hypothesized that FGM might be used as the material of the nail in PFNA device with the material composition of the nail gradually shifting from more stiff at the proximal side of the femur to more flexible 'iso-elastic' towards the distal side. This hypothesis can be evaluated from the long-term remodeling behavior of host femur and the stress distributions in the PFNA device and bone. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Diaphyseal Femur Fractures in Osteogenesis Imperfecta: Characteristics and Relationship With Bisphosphonate Treatment.

    Science.gov (United States)

    Trejo, Pamela; Fassier, François; Glorieux, Francis H; Rauch, Frank

    2017-05-01

    Several recent case reports have suggested that bisphosphonate treatment in individuals with osteogenesis imperfecta (OI) is causally related to atypical femur fractures. However, it is not known whether atypical femur fractures are actually more frequent in patients who have received bisphosphonates. In the present study, we retrospectively analyzed 166 femur fractures in 119 children with a diagnosis of OI that had not undergone intramedullary rodding procedures. A total of 130 fractures in 90 patients occurred in femurs with preexisting deformities (age at fracture between 1 month and 19.9 years; 43 girls). Because deformities are a typical cause of fracture in OI, deformed femurs were excluded from the analysis of atypical fractures. However, it was noted that in deformed femurs a transverse fracture pattern (one of the criteria of atypical fractures) was associated with a moderate to severe OI phenotype and not related to bisphosphonate treatment. Of the 36 fractures that occurred in nondeformed femurs (30 individuals; age at fracture between 1 month and 17.4 years; 13 girls), 11 (in nine children) occurred during bisphosphonate treatment. Three of these fractures (27%) resembled atypical femur fractures. Among the 25 femur fractures (23 patients) that occurred in the absence of prior bisphosphonate treatment, 8 (22%) resembled atypical femur fractures. Logistic regression analysis showed that bisphosphonate treatment history was not associated with the occurrence of atypical fractures. In contrast, the presence of moderate to severe OI (defined as any OI type other than OI type I) was strongly associated with atypical femur fractures. Thus, we observed an atypical appearance in about a quarter of nondeformed femur fractures that occurred in children with OI. Such atypical femur fractures seemed to be related to the severity of OI rather than to bisphosphonate treatment history. © 2016 American Society for Bone and Mineral Research. © 2016 American Society

  7. Does cementing the femoral component increase the risk of peri-operative mortality for patients having replacement surgery for a fracture of the neck of femur? Data from the National Hip Fracture Database.

    Science.gov (United States)

    Costa, M L; Griffin, X L; Pendleton, N; Pearson, M; Parsons, N

    2011-10-01

    Concerns have been reported to the United Kingdom National Patient Safety Agency, warning that cementing the femoral component during hip replacement surgery for fracture of the proximal femur may increase peri-operative mortality. The National Hip Fracture Database collects demographic and outcome data about patients with a fracture of the proximal femur from over 100 participating hospitals in the United Kingdom. We conducted a mixed effects logistic regression analysis of this dataset to determine whether peri-operative mortality was increased in patients who had undergone either hemiarthroplasty or total hip replacement using a cemented femoral component. A total of 16,496 patients from 129 hospitals were included in the analysis, which showed a small but significant adjusted survival benefit associated with cementing (odds ratio 0.83, 95% confidence interval 0.72 to 0.96). Other statistically significant variables in predicting death at discharge, listed in order of magnitude of effect, were gender, American Society of Anesthesiologists grade, age, walking accompanied outdoors and arthroplasty. Interaction terms between cementing and these other variables were sequentially added to, but did not improve, the model. This study has not shown an increase in peri-operative mortality as a result of cementing the femoral component in patients requiring hip replacement following fracture of the proximal femur.

  8. Influence of muscle groups' activation on proximal femoral growth tendency.

    Science.gov (United States)

    Yadav, Priti; Shefelbine, Sandra J; Pontén, Eva; Gutierrez-Farewik, Elena M

    2017-12-01

    Muscle and joint contact force influence stresses at the proximal growth plate of the femur and thus bone growth, affecting the neck shaft angle (NSA) and femoral anteversion (FA). This study aims to illustrate how different muscle groups' activation during gait affects NSA and FA development in able-bodied children. Subject-specific femur models were developed for three able-bodied children (ages 6, 7, and 11 years) using magnetic resonance images. Contributions of different muscle groups-hip flexors, hip extensors, hip adductors, hip abductors, and knee extensors-to overall hip contact force were computed. Specific growth rate for the growth plate was computed, and the growth was simulated in the principal stress direction at each element in the growth front. The predicted growth indicated decreased NSA and FA (of about [Formula: see text] over a four-month period) for able-bodied children. Hip abductors contributed the most, and hip adductors, the least, to growth rate. All muscles groups contributed to a decrease in predicted NSA ([Formula: see text]0.01[Formula: see text]-0.04[Formula: see text] and FA ([Formula: see text]0.004[Formula: see text]-[Formula: see text]), except hip extensors and hip adductors, which showed a tendency to increase the FA ([Formula: see text]0.004[Formula: see text]-[Formula: see text]). Understanding influences of different muscle groups on long bone growth tendency can help in treatment planning for growing children with affected gait.

  9. The evaluation of two references for restoring proximal femoral anatomy during total hip arthroplasty.

    Science.gov (United States)

    Unnanuntana, Aasis; Toogood, Paul; Hart, Daniel; Cooperman, Daniel; Grant, Richard E

    2010-04-01

    The morphologic features of the proximal femur are used in preoperative planning prior to total hip arthroplasty (THA). In this study we evaluated two references that have been widely used during THA to restore the normal anatomy of the proximal femur: (1) the distance from the lesser trochanter to the center of femoral head and (2) the anatomic relationship between the greater trochanter and the center of femoral head. We used digital photographs to compare 200 cadaveric femora in individuals who died prior to 40 years of age. Preoperative measurement of the distance from lesser trochanter to the center of femoral head from the contralateral hip is accurate to predict the measurement on the operated hip with correlation coefficients (r(2)) of 0.87. The ratio between femoral head diameter and distance from the lesser trochanter to the center of femoral head was consistent and reliable between genders and sides with an average value of 1.01 +/- 0.12. Thus, when the distance from the lesser trochanter to the center of femoral head is not discernible, this ratio can be used as a guide to determine proximal femoral geometry. Conversely, only 59% of the specimens had femoral head centers within 5 mm of the tip of greater trochanter. The correlation between sides of the relationship between the greater trochanter and the center of femoral head was moderate (r(2) = 0.46). Therefore, this relationship should not be used as the sole method to determine the normal anatomy of proximal femur. 2010 Wiley-Liss, Inc.

  10. The effects of hyperlipidemia on implant osseointegration in the mouse femur.

    Science.gov (United States)

    Keuroghlian, Armand; Barroso, Ana Dilza Viana; Kirikian, Gary; Bezouglaia, Olga; Tintut, Yin; Tetradis, Sotirios; Moy, Peter; Pirih, Flavia; Aghaloo, Tara

    2015-04-01

    A high-fat (HF) diet inducing hyperlipidemia has been associated with the pathophysiology of major diseases, such as atherosclerosis and osteoporosis. A HF diet has significant adverse effects on bone, including lower bone density, volume, and strength. Statins, drugs that lower serum cholesterol levels have beneficial effects on bone metabolism. Since the host's bone quantity, quality, and healing potential play a crucial role in osseointegration of dental implants, we hypothesized that hyperlipidemia may negatively affect implant osseointegration. In the present study, we evaluated the effects of hyperlipidemia on implant osseointegration in mice. Atherosclerosis susceptible C57BL/6J male mice were randomly placed on a control chow or a HF diet. After 12 weeks on the diet, each mouse received a titanium implant in the proximal metaphysis of the femur. The animals were humanely killed at 4 or 8 weeks after the implant surgery. Results showed that the mice fed a HF diet had significantly increased implant loss as well as decreased formation and strength of bone-to-implant interface. These results support the hypothesis that a HF diet can significantly compromise osseointegration, causing poor outcome in dental implant therapy.

  11. Biomechanical comparison of 2 different locking plate fixation methods in vancouver b1 periprosthetic femur fractures.

    Science.gov (United States)

    Pletka, Joshua D; Marsland, Daniel; Belkoff, Stephen M; Mears, Simon C; Kates, Stephen L

    2011-03-01

    Locking plates are commonly used to treat fractures around a well-fixed femoral component. The optimal construct should provide sufficient fixation while minimizing soft-tissue dissection. The purpose of the current study was to determine whether plate length, working length, or bone mineral density affects survival of locking plate fixation for Vancouver type B1 periprosthetic hip fractures. A transverse osteotomy was created just distal to cemented femoral prostheses in 9 pairs of cadaveric femurs. Fractures were stabilized with long (20-hole) or short (12-hole) locking plates that were secured proximally with cables and screws and distally with screws only. Specimens were then cycled 10 000 times at 2500 N of axial force and 15 Nm of torque to simulate full weightbearing. A motion capture system was used to record fracture displacement during cycling. Failure occurred in 5 long and 3 short plates, with no significant differences found in the number of cycles to failure. For the specimens that survived, there were no significant differences found between long and short plates for displacement or rotation observed at the fracture site. A shorter working length was not associated with increased failure rate. Lower bone mineral density was significantly associated with failure (P = .02). We concluded that long locked plates do not appear to offer a biomechanical advantage over short locking plates in terms of fixation survival, and that bone mineral density was a better predictor of failure than was the fixation construct type.

  12. Acute postoperative osteomyelitis in femur fracture: contribution of bone scintilography (case report)

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Natalie Ferreira; Rezende, Cleuza Maria de Faria; Sanchez-Ucros, Natalia; Laguardia, Priscilla [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Escola de Veterinaria; Diniz, Simone Odilia Fernandes; Cardoso, Valbert Nascimento [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Farmacia; Rodrigues, Carlos Jorge Simal [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina; Santos, Raquel Gouvea dos [Centro de Desenvolcimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia

    2009-07-01

    The treatment of bone fractures is aimed at consolidating and returns of function as soon as possible and can be performed by different methods. Treatment with the plate in fractures of the femur in bridge aims not to address the location of fracture and stabilize it, maintaining the anatomical axis by the fixation of proximal and distal segments. Postoperative follow-up of the fracture is necessary to evaluate the irrigation of the bone structure and the effect of the method. The scintigraphy is a method capable of assessing the degree of bone remodeling and the presence or absence of local bone homeostasis. The objective of this report is to present the case of a rabbit, male, which was subjected to osteotomy and fixation of the femoral diaphysis by means of the plate in the bridge. After 10 days the animal was subjected to scintigraphic and radiographic evaluations. The animal came to death and an autopsy was performed on the same when it was observed macroscopy consistent with acute osteomyelitis due to contamination postoperative time. Radiographic evaluation in acute osteomyelitis is unclear. The methods assist in the scintigraphic diagnosis of osteomyelitis by allowing the detection of functional changes in this infectious process. The bone scintigraphy with diphosphonates labeled with technetium-99m shows increased bone turnover in the infected area and its high sensitivity, even in an early stage makes it the method of choice in the diagnosis of acute osteomyelitis in patients without prior bone disease and bone radiologically normal. (author)

  13. Concomitant ipsilateral proximal tibia and femoral Hoffa fractures.

    Science.gov (United States)

    Jain, Anuj; Aggarwal, Prakash; Pankaj, Amite

    2014-01-01

    The aim of this study was to report our experience on concomitant ipsilateral proximal tibia and femoral Hoffa fractures. Nine patients (8 male, 1 female; mean age: 30.9; range: 19-49 years) presented to our emergency room with an ipsilateral proximal tibia and femoral Hoffa fracture, following road traffic accident. Six patients had open fracture. Two patients had ipsilateral femoral shaft fracture, two patients had fracture of intercondylar part of distal femur, one had fracture of patella and one had fracture of both bones of the leg. Out of nine Hoffa's fracture eight involved lateral and one involved medial femoral condyle. There were five type II, two type VI, one type I and one type IV proximal tibial fracture according to Schatzker classification. Mean duration of follow-up was 13 months (range: 9-21 months). At final follow-up, all fractures united. Mean knee society score was 163 (range: 127-182). Mean ROM at knee joint was 97.4 degrees (75°-115°). Our results suggest that in this combination of intraarticular fractures anatomic reduction and rigid fixation followed by early mobilization reveal satisfactory results.

  14. Geometrical method of decoupling

    Directory of Open Access Journals (Sweden)

    C. Baumgarten

    2012-12-01

    Full Text Available The computation of tunes and matched beam distributions are essential steps in the analysis of circular accelerators. If certain symmetries—like midplane symmetry—are present, then it is possible to treat the betatron motion in the horizontal, the vertical plane, and (under certain circumstances the longitudinal motion separately using the well-known Courant-Snyder theory, or to apply transformations that have been described previously as, for instance, the method of Teng and Edwards. In a preceding paper, it has been shown that this method requires a modification for the treatment of isochronous cyclotrons with non-negligible space charge forces. Unfortunately, the modification was numerically not as stable as desired and it was still unclear, if the extension would work for all conceivable cases. Hence, a systematic derivation of a more general treatment seemed advisable. In a second paper, the author suggested the use of real Dirac matrices as basic tools for coupled linear optics and gave a straightforward recipe to decouple positive definite Hamiltonians with imaginary eigenvalues. In this article this method is generalized and simplified in order to formulate a straightforward method to decouple Hamiltonian matrices with eigenvalues on the real and the imaginary axis. The decoupling of symplectic matrices which are exponentials of such Hamiltonian matrices can be deduced from this in a few steps. It is shown that this algebraic decoupling is closely related to a geometric “decoupling” by the orthogonalization of the vectors E[over →], B[over →], and P[over →], which were introduced with the so-called “electromechanical equivalence.” A mathematical analysis of the problem can be traced down to the task of finding a structure-preserving block diagonalization of symplectic or Hamiltonian matrices. Structure preservation means in this context that the (sequence of transformations must be symplectic and hence canonical. When

  15. Geometric Computing for Freeform Architecture

    KAUST Repository

    Wallner, J.

    2011-06-03

    Geometric computing has recently found a new field of applications, namely the various geometric problems which lie at the heart of rationalization and construction-aware design processes of freeform architecture. We report on our work in this area, dealing with meshes with planar faces and meshes which allow multilayer constructions (which is related to discrete surfaces and their curvatures), triangles meshes with circle-packing properties (which is related to conformal uniformization), and with the paneling problem. We emphasize the combination of numerical optimization and geometric knowledge.

  16. Geometric phase shifting digital holography.

    Science.gov (United States)

    Jackin, Boaz Jessie; Narayanamurthy, C S; Yatagai, Toyohiko

    2016-06-01

    A new phase shifting digital holographic technique using a purely geometric phase in Michelson interferometric geometry is proposed. The geometric phase in the system does not depend upon either optical path length or wavelength, unlike dynamic phase. The amount of geometric phase generated is controllable through a rotating wave plate. The new approach has unique features and major advantages in holographic measurement of transparent and reflecting three-dimensional (3D) objects. Experimental results on surface shape measurement and imaging of 3D objects are presented using the proposed method.

  17. [Surgical outcome in pertrochanteric femur fracture: the impact of osteoporosis. Comparison between DHS and percutaneous compression plate].

    Science.gov (United States)

    Knobe, M; Münker, R; Schmidt-Rohlfing, B; Sellei, R M; Schubert, H; Erli, H J

    2008-01-01

    The dynamic hip screw (DHS) often shows an impared outcome and a high incidence of therapeutic failure in patients with osteoporotic pertrochanteric femur fractures. This is caused predominantly by a fracture collapse and appears often in unstable fractures (31A2, 31A3). In a prospectively documented clinical study, we examined whether or not the percutaneous compression plate (PCCP, Gotfried) offers advantages following osteoporotic fractures. From August 2003 to December 2005, 103 patients underwent internal fixation with the DHS (n = 40, age 76.1, ASA 2.9) or with the PCCP (n = 63, age 76.9, ASA 2.8). Proximal femurs were classified with the Singh grading system, which uses six grades of trabecular patterns to describe the degree of osteoporosis. Reexamination of the patients (27 DHS, 43 PCCP) was performed on average 18 months later. The PCCP was implanted into very osteoporotic femurs (Singh 2) in less time than the DHS (47 vs. 79 min). These patients treated with PCCP showed no difference in blood loss, but tended to have better outcomes (Merle d'Aubigné, Harris hip score) than those treated with DHS. Life quality, subjectively measured with the visual analogue score, was significantly better in the PCCP group with high-grade osteoporosis (Singh 2). The outcome after implantation of the PCCP was not correlated to the Singh index in stable or in unstable fractures. Mechanical complications occurred especially in unstable fractures (re-operation rate: DHS 4/18 [22 %], PCCP 3/29 [10 %], p = 0.266), without correlation to the Singh index. Excluding the avoidable complication of loosening of the screw-barrel portion, the re-operation rate for the PCCP was 3 % (cut-out: 1/29, p = 0.042) in unstable fractures. Use of the minimally invasive PCCP technique in osteoporotic pertrochanteric femur fractures provides an alternative to the dynamic hip screw, especially with regard to surgical time and outcome. Advantages occurred also in the re-operation rate following

  18. Is the rotation of the femural head a potential initiation for cutting out? A theoretical and experimental approach

    LENUS (Irish Health Repository)

    Lenich, Andreas

    2011-04-22

    Abstract Background Since cut-out still remains one of the major clinical challenges in the field of osteoporotic proximal femur fractures, remarkable developments have been made in improving treatment concepts. However, the mechanics of these complications have not been fully understood. We hypothesize using the experimental data and a theoretical model that a previous rotation of the femoral head due to de-central implant positioning can initiate a cut-out. Methods In this investigation we analysed our experimental data using two common screws (DHS\\/Gamma 3) and helical blades (PFN A\\/TFN) for the fixation of femur fractures in a simple theoretical model applying typical gait pattern on de-central positioned implants. In previous tests during a forced implant rotation by a biomechanical testing machine in a human femoral head the two screws showed failure symptoms (2-6Nm) at the same magnitude as torques acting in the hip during daily activities with de-central implant positioning, while the helical blades showed a better stability (10-20Nm). To calculate the torque of the head around the implant only the force and the leverarm is needed (N [Nm] = F [N] * × [m]). The force F is a product of the mass M [kg] multiplied by the acceleration g [m\\/s2]. The leverarm is the distance between the center of the head of femur and the implant center on a horizontal line. Results Using 50% of 75 kg body weight a torque of 0.37Nm for the 1 mm decentralized position and 1.1Nm for the 3 mm decentralized position of the implant was calculated. At 250% BW, appropriate to a normal step, torques of 1.8Nm (1 mm) and 5.5Nm (3 mm) have been calculated. Comparing of the experimental and theoretical results shows that both screws fail in the same magnitude as torques occur in a more than 3 mm de-central positioned implant. Conclusion We conclude the center-center position in the head of femur of any kind of lag screw or blade is to be achieved to minimize rotation of the femoral head

  19. Biomechanical effects of harvesting bone graft with the Reamer/Irrigator/Aspirator on the adult femur: a cadaver study.

    Science.gov (United States)

    Silva, Jason A; McCormick, Jeremy J; Reed, Mark A; Morse, Andrew S; Heffernan, Michael J; Lavado, Robert D; Billiar, Kristen; Wixted, John J

    2010-11-01

    Test the biomechanical properties of femurs that have undergone reaming with the Reamer Irrigator Aspirator (RIA) device with an aim to prove no difference in torsional strength between matched pairs. Intact femurs were harvested from embalmed cadavers, representing 19 matched pairs. One femur from each pair was randomly selected to undergo reaming using the RIA to 15 mm. The bones were then cut and potted using a uniform jig for testing. Each specimen was tested in torsion and torsional stiffness was calculated for each pair. Samples were loaded until fracture or 11 3 N·m of torque. Nine of the reamed specimens and 13 of the unreamed samples remained intact until the machine limit of 113 N·m was reached, representing approximately four times the peak torque of 30N·m seen with stair climbing [Garino J, Beredjiklian P. Core Knowledge in Orthopaedics: Adult Reconstruction and Arthroplasty. Chapter 1, page 33. Mosby, 2007]. Mean torsional stiffness for the reamed group was 532.1 N·m/rad (SD = 208.2), and the unreamed was 546.2 N·m/rad (SD=206). Torsional load capacity was calculated for all specimens and compared in groups in which both reamed and unreamed specimens failed. In these five groups, mean load capacity was 80.6 Nm (SD = 9.5) for the reamed group, and 85 Nm (SD = 16.1) for the unreamed group. 17 of our reamed specimens and all of our unreamed specimens withstood normal physiologic load seen with stair climbing. In addition, 16 of 19 reamed specimens remained intact at twice this load. The specimen in the reamed group with the lowest torsional load capacity was eccentrically reamed in the distal anterior cortex highlighting potential complications. Given these findings, reaming the cortex of the femur with the RIA device for the purpose of harvesting bone graft does not appear to dramatically diminish the mechanical properties of the cortex or require postoperative weight bearing restrictions. However, careful attention must be paid to technique as

  20. A Modified Technique of Fixation for Proximal Femoral Valgus Osteotomy in Abnormal Bone: A Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Logheswaren S

    2017-07-01

    Full Text Available The ideal size of intramedullary device to fix corrective osteotomy of proximal femur in abnormal bone in children and small patients may not be easily available. We report the successful use of Rush rod in combination with multiple Kirschner wires to fix the corrective osteotomy of coxa vara and shepherd crook deformity in two patients with osteogenesis imperfecta and fibrous dysplasia. The union was achieved on time, neck shaft angle and rotation were maintained.

  1. Proximal Femoral Fracture in Hip Arthrodesis Treated with Double Reconstruction Plates

    Directory of Open Access Journals (Sweden)

    Shunsuke Asakawa

    2017-01-01

    Full Text Available We present a rare clinical case of a 90-year-old female who sustained a proximal femoral neck fracture following long-standing hip arthrodesis. Since the fracture occurred relatively proximally and involved the pelvis, double-plate fixation was chosen to achieve rigid fixation. The reconstruction plate was placed at the posterior and anterior columns individually through single vertical incision. She was treated successfully, and she attained preinjury activity level. Proximal femoral fractures in arthrodesed hips need to be recognized as a fracture between the pelvis and femur. Rotational stress from the trunk and lower extremity requires rigid fixation to minimize the increase of displacement and the risk for nonunion.

  2. Modified Van Nes rotationplasty for osteosarcoma of the proximal tibia in children.

    Science.gov (United States)

    de Bari, A; Krajbich, J I; Langer, F; Hamilton, E L; Hubbard, S

    1990-11-01

    Above-knee amputation has been the traditional treatment for osteosarcoma of the proximal tibia. Recent advances in chemotherapy have encouraged the development of limb-salvage techniques. Van Nes rotationplasty for malignant lesions of the distal femur has increased in popularity as a reconstructive technique, but no similar procedure has been described for lesions of the proximal tibia. We have developed a modified rotationplasty for this lesion and have performed it in four children. The surgical technique, postoperative management and results of the procedure are described. Two patients had delayed wound healing. No other complications have developed and our patients were disease-free at follow-up, while the appearance of the leg was well accepted by the patients and their parents. This procedure is a useful addition to the armamentarium of the tumour surgeon for the treatment of malignant lesions of the proximal tibia.

  3. Femur fracture classification in women with a history of breast cancer

    OpenAIRE

    Chau, Stephanie; Chandra, Malini; Grimsrud, Christopher D.; Gonzalez, Joel R.; Hui, Rita L; Lo, Joan C.

    2014-01-01

    Purpose: Women with breast cancer are at increased risk for femur fracture. Contributing factors include estrogen deficiency, cancer-related therapies, or direct bone involvement. This study examines fracture subtypes in women with prior breast cancer experiencing a femur fracture. Methods: Women age ≥50 years old with a history of invasive breast cancer who experienced a femur fracture were identified during 2005–2012. Fracture site was classified by hospital diagnosis (for hip) and/or ra...

  4. Simultaneous Periprosthetic Fractures of the Femur and the Acetabulum After Bipolar Hip Arthroplasty

    OpenAIRE

    Verettas, Dionysios-Alexandros; Chloropoulou, Pelagia-Paraskevi; Drosos, Georgios; Vogiatzaki, Theodosia; Tilkeridis, Konstantinos; Kazakos, Konstantinos

    2016-01-01

    Patient: Female, 68 Final Diagnosis: Periprosthetic fractures of the acetabulum and femur after bipolar hip arthroplasty Symptoms: Inability to walk Medication: ? Clinical Procedure: Revision cup and internal fixation femur Specialty: Orhopedics and Traumatology Objective: Rare co-existance of disease or pathology Background: Although periprosthetic fractures of the femur are a recognized complication of total hip arthroplasty, periprosthetic fractures of the acetabulum are rare. Simultaneous...

  5. Geometric inequalities methods of proving

    CERN Document Server

    Sedrakyan, Hayk

    2017-01-01

    This unique collection of new and classical problems provides full coverage of geometric inequalities. Many of the 1,000 exercises are presented with detailed author-prepared-solutions, developing creativity and an arsenal of new approaches for solving mathematical problems. This book can serve teachers, high-school students, and mathematical competitors. It may also be used as supplemental reading, providing readers with new and classical methods for proving geometric inequalities. .

  6. Static or dynamic intramedullary nailing of femur and tibia.

    Science.gov (United States)

    Omerovic, Djemil; Lazovic, Faruk; Hadzimehmedagic, Amel

    2015-04-01

    The basic principle of non-surgical fracture treatment is to restore the original anatomical position of fractured fragments by different techniques, without direct access to the bone and without further traumatizing of tissues. Intramedullary nailing is synthesis and consolidation of fracture fragments with the main goal to gain strength and permanent placement of the implants. Two techniques of intramedullary osteosynthesis are used: with dynamic or with static intramedullary nail. Dynamization include conversion of static nail by removing screws from the longest fragment. The aim of this study is to determine whether there is a difference in the speed and quality of healing of the type A and B fractures of the femur and tibia treated by static or dynamic intramedullary nails and to compare the results. The study was conducted at the Clinic for Orthopaedics and Traumatology, Clinical Center University Sarajevo from January 2004 to June 2009. The study was retrospective-prospective, manipulative, controlled and it was conducted on a total of 129 patients with closed fractures of the diaphysis of the femur and tibia type A and type B, with different segments of bone, regardless of sex and age structure, with the exception of children under 14 years of age. Precisely there were 47 patients with femoral fractures and 82 patients with tibial fractures. The average number of weeks of healing femoral and tibial fractures was slightly in advantage of static intramedullary osteosynthesis, it was 17.08 weeks (SD=3.382). The average number of weeks of healing in 23 patients with fractures of the femur, treated by dynamic intramedullary osteosynthesis was 17.83 (SD=2.978). We can conclude that static intramedullary nailing osteosynthesis unable movements between fragments which directly stimulates bone formation and formation of minimal callus. Static intramedullary osteosynthesis resolve the problem of stabilizing the fracture, limb shortening and rotation of fragments.

  7. Indomethacin induced avascular necrosis of head of femur

    OpenAIRE

    Prathapkumar, K; Smith, I; Attara, G

    2000-01-01

    Chemically induced avascular necrosis of bone is a well documented entity. Indomethacin is one of the causes of this condition but is often difficult to recognise. Review of the literature shows that only one case of indomethacin induced avascular necrosis has been reported in the English language between 1966 and the present.
The case of a young healthy man, who developed avascular necrosis of head of femur after prolonged administration of indomethacin, is reported here.


Keywords: indomet...

  8. Antenna with Dielectric Having Geometric Patterns

    Science.gov (United States)

    Dudley, Kenneth L. (Inventor); Elliott, Holly A. (Inventor); Cravey, Robin L. (Inventor); Connell, John W. (Inventor); Ghose, Sayata (Inventor); Watson, Kent A. (Inventor); Smith, Jr., Joseph G. (Inventor)

    2013-01-01

    An antenna includes a ground plane, a dielectric disposed on the ground plane, and an electrically-conductive radiator disposed on the dielectric. The dielectric includes at least one layer of a first dielectric material and a second dielectric material that collectively define a dielectric geometric pattern, which may comprise a fractal geometry. The radiator defines a radiator geometric pattern, and the dielectric geometric pattern is geometrically identical, or substantially geometrically identical, to the radiator geometric pattern.

  9. Some Properties of Fuzzy Soft Proximity Spaces

    Science.gov (United States)

    Demir, İzzettin; Özbakır, Oya Bedre

    2015-01-01

    We study the fuzzy soft proximity spaces in Katsaras's sense. First, we show how a fuzzy soft topology is derived from a fuzzy soft proximity. Also, we define the notion of fuzzy soft δ-neighborhood in the fuzzy soft proximity space which offers an alternative approach to the study of fuzzy soft proximity spaces. Later, we obtain the initial fuzzy soft proximity determined by a family of fuzzy soft proximities. Finally, we investigate relationship between fuzzy soft proximities and proximities. PMID:25793224

  10. PROXIMITY MANAGEMENT IN CRISIS CONDITIONS

    Directory of Open Access Journals (Sweden)

    Ion Dorin BUMBENECI

    2010-01-01

    Full Text Available The purpose of this study is to evaluate the level of assimilation for the terms "Proximity Management" and "Proximity Manager", both in the specialized literature and in practice. The study has two parts: the theoretical research of the two terms, and an evaluation of the use of Proximity management in 32 companies in Gorj, Romania. The object of the evaluation resides in 27 companies with less than 50 employees and 5 companies with more than 50 employees.

  11. Geometric Mixing, Peristalsis, and the Geometric Phase of the Stomach.

    Science.gov (United States)

    Arrieta, Jorge; Cartwright, Julyan H E; Gouillart, Emmanuelle; Piro, Nicolas; Piro, Oreste; Tuval, Idan

    2015-01-01

    Mixing fluid in a container at low Reynolds number--in an inertialess environment--is not a trivial task. Reciprocating motions merely lead to cycles of mixing and unmixing, so continuous rotation, as used in many technological applications, would appear to be necessary. However, there is another solution: movement of the walls in a cyclical fashion to introduce a geometric phase. We show using journal-bearing flow as a model that such geometric mixing is a general tool for using deformable boundaries that return to the same position to mix fluid at low Reynolds number. We then simulate a biological example: we show that mixing in the stomach functions because of the "belly phase," peristaltic movement of the walls in a cyclical fashion introduces a geometric phase that avoids unmixing.

  12. High strain rate response of rabbit femur bones.

    Science.gov (United States)

    Shunmugasamy, Vasanth Chakravarthy; Gupta, Nikhil; Coelho, Paulo G

    2010-11-16

    Strain rate dependence of the mechanical response of hard tissues has led to a keen interest in their dynamic properties. The current study attempts to understand the high strain rate characteristics of rabbit femur bones. The testing was conducted using a split-Hopkinson pressure bar equipped with a high speed imaging system to capture the fracture patterns. The bones were also characterized under quasi-static compression to enable comparison with the high strain rate results. The quasi-static compressive moduli of the epiphyseal and diaphyseal regions were measured to be in the range of 2-3 and 5-7GPa, respectively. Under high strain rate loading conditions the modulus is observed to increase with strain rate and attains values as high as 15GPa for epiphyseal and 30GPa for diaphyseal regions of the femur. The strength at high strain rate was measured to be about twice the quasi-static strength value. A large number of small cracks initiated on the specimen surface close to the incident bar. Coalescence of crack branches leading to fewer large cracks resulted in specimen fragmentation. In comparison, the quasi-static failure was due to shear cracking. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Combined spinal epidural anesthesia in achondroplastic dwarf for femur surgery

    Directory of Open Access Journals (Sweden)

    Rochana Girish Bakhshi

    2011-11-01

    Full Text Available Achondroplasia is the commonest form of short-limbed dwarfism and occurs in 1:26,000- 40,000 live births. This is an autosomal dominant disorder with abnormal endochondral ossification whereas periosteal and intramembranous ossification are normal. The basic abnormality is a disturbance of cartilage formation mainly at the epiphyseal growth plates and at the base of the skull. The anesthetic management of achondroplastic dwarfs is a challenge to the anesthesiologist. Both regional as well as general anesthesia have their individual risks and consequences. We report a case of an achondroplastic dwarf in whom combined spinal epidural anesthesia was used for fixation of a fractured femur. The patient had undergone previous femur surgery under general anesthesia since he had been informed that spinal anesthesia could be very problematic. There was no technical difficulty encountered during the procedure and an adequate level was achieved with low-dose local anesthetics without any problem. Postoperative pain relief was offered for three consecutive postoperative days using epidural tramadol. We discuss the anesthetic issues and highlight the role of combined spinal epidural anesthesia with low-dose local anesthetics in this patient. This approach also helped in early ambulation and postoperative pain relief.

  14. All-polyethylene tibial components in distal femur limb-salvage surgery: a finite element analysis based on promising clinical outcomes.

    Science.gov (United States)

    Tang, Fan; Zhou, Yong; Zhang, Wenli; Min, Li; Shi, Rui; Luo, Yi; Duan, Hong; Tu, Chongqi

    2017-04-04

    Whether all-polyethylene tibial (APT) components are beneficial to patients who received distal femur limb-salvage surgery lacks high-quality clinical follow-up and mechanical evidence. This study aimed to investigate the biomechanics of the distal femur reconstructed with APT tumor knee prostheses using finite element (FE) analysis based on our previous, promising clinical outcome. Three-dimensional FE models that use APT and metal-backed tibial (MBT) prostheses to reconstruct distal femoral bone defects were developed and input into the Abaqus FEA software version 6.10.1. Mesh refinement tests and gait simulation with a single foot both in the upright and 15°-flexion positions with mechanical loading were conducted. Stress distribution analysis was compared between APT and MBT at the two static positions. For both prosthesis types, the stress was concentrated on the junction of the stem and shaft, and the maximum stress in the femoral axis base was more than 100 Mpa. The stress on the tibial surface was relatively distributed, which was 1-19 MPa. The stress on the tibial bone-cement layer of the APT prosthesis was approximately 20 times higher than that on the MBT prosthesis in the same region. The stress on the proximal tibial cancellous bone and cortical bone of the APT prosthesis was 3-5 times greater than that of the MBT prosthesis, and it was more distributed. Although the stress of bone-cement around the APT component is relatively high, the stress was better distributed at the polyethylene-cement-bone interface in APT than in MBT prosthesis, which effectively protects the proximal tibia in distal femur tumor knee prosthesis replacement. These results should be considered when selecting the appropriate tibial component for a patient, especially under the foreseeable conditions of osteoporosis.

  15. A hybrid FDTD-Rayleigh integral computational method for the simulation of the ultrasound measurement of proximal femur.

    Science.gov (United States)

    Cassereau, Didier; Nauleau, Pierre; Bendjoudi, Aniss; Minonzio, Jean-Gabriel; Laugier, Pascal; Bossy, Emmanuel; Grimal, Quentin

    2014-07-01

    The development of novel quantitative ultrasound (QUS) techniques to measure the hip is critically dependent on the possibility to simulate the ultrasound propagation. One specificity of hip QUS is that ultrasounds propagate through a large thickness of soft tissue, which can be modeled by a homogeneous fluid in a first approach. Finite difference time domain (FDTD) algorithms have been widely used to simulate QUS measurements but they are not adapted to simulate ultrasonic propagation over long distances in homogeneous media. In this paper, an hybrid numerical method is presented to simulate hip QUS measurements. A two-dimensional FDTD simulation in the vicinity of the bone is coupled to the semi-analytic calculation of the Rayleigh integral to compute the wave propagation between the probe and the bone. The method is used to simulate a setup dedicated to the measurement of circumferential guided waves in the cortical compartment of the femoral neck. The proposed approach is validated by comparison with a full FDTD simulation and with an experiment on a bone phantom. For a realistic QUS configuration, the computation time is estimated to be sixty times less with the hybrid method than with a full FDTD approach. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Energy absorption during impact on the proximal femur is affected by body mass index and flooring surface.

    Science.gov (United States)

    Bhan, Shivam; Levine, Iris C; Laing, Andrew C

    2014-07-18

    Impact mechanics theory suggests that peak loads should decrease with increase in system energy absorption. In light of the reduced hip fracture risk for persons with high body mass index (BMI) and for falls on soft surfaces, the purpose of this study was to characterize the effects of participant BMI, gender, and flooring surface on system energy absorption during lateral falls on the hip with human volunteers. Twenty university-aged participants completed the study with five men and five women in both low BMI (27.5 kg/m(2)) groups. Participants underwent lateral pelvis release experiments from a height of 5 cm onto two common floors and four safety floors mounted on a force plate. A motion-capture system measured pelvic deflection. The energy absorbed during the initial compressive phase of impact was calculated as the area under the force-deflection curve. System energy absorption was (on average) 3-fold greater for high compared to low BMI participants, but no effects of gender were observed. Even after normalizing for body mass, high BMI participants absorbed 1.8-fold more energy per unit mass. Additionally, three of four safety floors demonstrated significantly increased energy absorption compared to a baseline resilient-rolled-sheeting system (% increases ranging from 20.7 to 28.3). Peak system deflection was larger for high BMI persons and for impacts on several safety floors. This study indicates that energy absorption may be a common mechanism underlying the reduced risk of hip fracture for persons with high BMI and for those who fall on soft surfaces. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  17. Does Fracture Affect the Healing Time or Frequency of Recurrence in a Simple Bone Cyst of the Proximal Femur?

    National Research Council Canada - National Science Library

    Cha, Soo Min; Shin, Hyun Dae; Kim, Kyung Cheon; Park, Jung Woo

    2014-01-01

    ... fracture in terms of (1) healing time, (2) frequency and timing of recurrence, and (3) complications.From 1995 to 2005, 54 patients diagnosed with femoral simple bone cysts were treated and followed for a minimum of 8 years...

  18. Geometric procedures for civil engineers

    CERN Document Server

    Tonias, Elias C

    2016-01-01

    This book provides a multitude of geometric constructions usually encountered in civil engineering and surveying practice.  A detailed geometric solution is provided to each construction as well as a step-by-step set of programming instructions for incorporation into a computing system. The volume is comprised of 12 chapters and appendices that may be grouped in three major parts: the first is intended for those who love geometry for its own sake and its evolution through the ages, in general, and, more specifically, with the introduction of the computer. The second section addresses geometric features used in the book and provides support procedures used by the constructions presented. The remaining chapters and the appendices contain the various constructions. The volume is ideal for engineering practitioners in civil and construction engineering and allied areas.

  19. Geometric group theory an introduction

    CERN Document Server

    Löh, Clara

    2017-01-01

    Inspired by classical geometry, geometric group theory has in turn provided a variety of applications to geometry, topology, group theory, number theory and graph theory. This carefully written textbook provides a rigorous introduction to this rapidly evolving field whose methods have proven to be powerful tools in neighbouring fields such as geometric topology. Geometric group theory is the study of finitely generated groups via the geometry of their associated Cayley graphs. It turns out that the essence of the geometry of such groups is captured in the key notion of quasi-isometry, a large-scale version of isometry whose invariants include growth types, curvature conditions, boundary constructions, and amenability. This book covers the foundations of quasi-geometry of groups at an advanced undergraduate level. The subject is illustrated by many elementary examples, outlooks on applications, as well as an extensive collection of exercises.

  20. 'Pathological' fracture of the femur -a complication of failed total hip ...

    African Journals Online (AJOL)

    Ten patients with a major femur fracture complicating total hip arthroplasty were seen at the Princess Alice Orthopaedic Hospital between June 1986 and May 1988. Four cases were intra-operative fractures sustained at revision surgery and 6 were late postoperative fractures of the femur associated with minimal trauma, ...

  1. Femur fracture classification in women with a history of breast cancer

    Directory of Open Access Journals (Sweden)

    Stephanie Chau

    2014-05-01

    Conclusion: Most femur fractures in women with prior breast cancer occurred in the hip. Among younger women and those experiencing diaphyseal fractures, a larger proportion were pathologic and some were found to be atypical. Further studies should examine risk factors for femur fracture in women with breast cancer with specific attention to fracture subtype and pharmacologic exposures.

  2. Pipkin Fractures: Fracture of the Head of Femur A Case Report ...

    African Journals Online (AJOL)

    Pipkin fracture is the fracture of the head of the femur. It can be associated with neck of femur fracture or / and posterior dislocation of the hip. This fracture is very rare fracture and has not been reported at our sub- region. We present this fracture in a 26 year old with a type I Pipkin fracture treated with closed reduction and ...

  3. Evaluation of the isometry of different points of the patella and femur for medial patellofemoral ligament reconstruction.

    Science.gov (United States)

    Gobbi, Riccardo Gomes; Pereira, César Augusto Martins; Sadigursky, David; Demange, Marco Kawamura; Tírico, Luis Eduardo Passarelli; Pécora, José Ricardo; Camanho, Gilberto Luis

    2016-10-01

    The location of patellar and femoral fixation of the graft in medial patellofemoral ligament reconstructions has been widely discussed. This study aimed to assess the distances between different patellar and femoral fixation points to identify the least anisometric pairs of points. Ten cadaver knees were attached to an apparatus that simulated an active range of motion of 120°, with three metallic markers fixed onto the medial side of the patella, and seven markings onto the medial epicondyle. The examined points included the proximal patella pole (1), the patellar center (3), the midpoint between points 1 and 3 (2), a point directly on the epicondyle (6), points 5mm anterior (5) and posterior (7) to the epicondyle, points 5mm anterior to point 5 (4) and 5mm posterior to point 7 (8), and points 5mm proximal (9) and distal (10) to the epicondyle. The distances between patella and femur points were measured by a photogrammetry system at 15° intervals. The pair of points that exhibited the lowest average variability in distance, and hence was the most isometric, was the patella center combined with the anterior to the medial femoral epicondyle. The pairs of points that exhibited the highest average variability in distance, and hence were the least isometric, were the ones located distal or posterior to the medial femoral epicondyle, with less influence by the patellar location. Surgeons should avoid positioning the graft distally or posterior to the epicondyle due to the increase in anisometry. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Geometric Langlands From Six Dimensions

    CERN Document Server

    Witten, Edward

    2010-01-01

    Geometric Langlands duality is usually formulated as a statement about Riemann surfaces, but it can be naturally understood as a consequence of electric-magnetic duality of four-dimensional gauge theory. This duality in turn is naturally understood as a consequence of the existence of a certain exotic supersymmetric conformal field theory in six dimensions. The same six-dimensional theory also gives a useful framework for understanding some recent mathematical results involving a counterpart of geometric Langlands duality for complex surfaces. (This article is based on a lecture at the Raoul Bott celebration, Montreal, June 2008.)

  5. Asymptotic geometric analysis, part I

    CERN Document Server

    Artstein-Avidan, Shiri

    2015-01-01

    The authors present the theory of asymptotic geometric analysis, a field which lies on the border between geometry and functional analysis. In this field, isometric problems that are typical for geometry in low dimensions are substituted by an "isomorphic" point of view, and an asymptotic approach (as dimension tends to infinity) is introduced. Geometry and analysis meet here in a non-trivial way. Basic examples of geometric inequalities in isomorphic form which are encountered in the book are the "isomorphic isoperimetric inequalities" which led to the discovery of the "concentration phenomen

  6. Catching homologies by geometric entropy

    Science.gov (United States)

    Felice, Domenico; Franzosi, Roberto; Mancini, Stefano; Pettini, Marco

    2018-02-01

    A geometric entropy is defined in terms of the Riemannian volume of the parameter space of a statistical manifold associated with a given network. As such it can be a good candidate for measuring networks complexity. Here we investigate its ability to single out topological features of networks proceeding in a bottom-up manner: first we consider small size networks by analytical methods and then large size networks by numerical techniques. Two different classes of networks, the random graphs and the scale-free networks, are investigated computing their Betti numbers and then showing the capability of geometric entropy of detecting homologies.

  7. A geometric approach to complexity.

    Science.gov (United States)

    Ay, Nihat; Olbrich, Eckehard; Bertschinger, Nils; Jost, Jürgen

    2011-09-01

    We develop a geometric approach to complexity based on the principle that complexity requires interactions at different scales of description. Complex systems are more than the sum of their parts of any size and not just more than the sum of their elements. Using information geometry, we therefore analyze the decomposition of a system in terms of an interaction hierarchy. In mathematical terms, we present a theory of complexity measures for finite random fields using the geometric framework of hierarchies of exponential families. Within our framework, previously proposed complexity measures find their natural place and gain a new interpretation.

  8. Prosthetic management 56 years after rotationplasty due to proximal femoral focal deficiency (PFFD).

    Science.gov (United States)

    Roux, N; Pieters, S

    2007-09-01

    Proximal femoral focal deficiency (PFFD) is a rare congenital anomaly of the femur. Rotationplasty has been described as a reconstructive procedure in the management of PFFD. A 68-year-old woman with PFFD of the right leg and rotationplasty at the age of 12 years had prosthetic fitting problems after a fall. The authors describe the analysis of the prosthetic fitting problems and the considerations made in prosthetic management. Following a fall, 56 years after rotationplasty, this woman has a good prosthetic fitting and a satisfying level of functioning.

  9. [Progress on tantalum rod implanting for the treatment of femur head necrosis].

    Science.gov (United States)

    Tang, Xiao-kang; Ye, Fu-sheng; Tong, Pei-jian; Fan, Yan-hua; Li, Min; Ying, Hang; Xiao, Lu-wei

    2013-07-01

    Incorrect treatment for femur head necrosis can cause collapse of femoral head and tresult in severe harm for the patients (especially for the patient with middle-aged and young). The structure and mechanics characteristics of tantalum rod is similar to bone tissue, it higher strength and can adapt the internal environment of organism, so it has a large potency in treating femur head necrosis. Treatment of early femur head necrosis with tantalum rod implanting had alreadly widey applied at home and abroad, the method has the advantages of simple operation, little risk, less complication and beseems the patient with stage I - II of ARCO. But reasons that the difficult diagnosis of early femur head necrosis, localized effect of tantalum rod, different experience of medical worker,caused the contentions about effect of tantalum rod implanting. With development of science, tantalum rod implanting combined with correlative biotechnology should raise the effect in treating femur head necrosis.

  10. Simultaneous Periprosthetic Fractures of the Femur and the Acetabulum After Bipolar Hip Arthroplasty.

    Science.gov (United States)

    Verettas, Dionysios-Alexandros; Chloropoulou, Pelagia-Paraskevi; Drosos, Georgios; Vogiatzaki, Theodosia; Tilkeridis, Konstantinos; Kazakos, Konstantinos

    2016-12-22

    BACKGROUND Although periprosthetic fractures of the femur are a recognized complication of total hip arthroplasty, periprosthetic fractures of the acetabulum are rare. Simultaneous periprosthetic fractures of both the acetabulum and the femur have not been reported, to our knowledge. CASE REPORT We report a simultaneous fracture of the acetabulum and the femur in a 68-year-old female patient who had previously sustained a subcapital fracture of the femur, treated with a bipolar uncemented prosthesis. We discuss the possible mechanism of this combination of fractures. CONCLUSIONS Simultaneous periprosthetic fractures of the femur and the acetabulum can occur if, in the presence of osteoporotic bone, the metallic femoral head has migrated medially in the acetabulum while the femoral stem is not loose.

  11. Osteoporosis or Low Bone Mass at the Femur Neck or Lumbar Spine in Older Adults: United States, 2005-2008

    Science.gov (United States)

    ... Order from the National Technical Information Service NCHS Osteoporosis or Low Bone Mass at the Femur Neck ... Survey, 2005–2008. What is the prevalence of osteoporosis or low bone mass at the femur neck ...

  12. Retrograde nailing for distal femur fractures in the elderly

    Directory of Open Access Journals (Sweden)

    Giddie Jasdeep

    2015-01-01

    Full Text Available Introduction: We report the results of treating a series of 56 fractures in 54 elderly patients with a distal femur fracture with a retrograde femoral nail. Methods: Fifty-four of the nails were inserted percutaneously with a closed reduction. After surgery all patients were allowed to weight bear as tolerated. Four fractures were supported in a temporary external splint. Results: The mean age of patients was 80.6 years (range 51–103 years, 52/54 (96% were females. There were no cases of nail related complications and no re-operations were required. One patient was lost to follow up. The 30-day mortality was 5/54 (9.3% and the one year mortality was 17/54 (31.5%. Conclusions: Distal femoral nail fixation provides a good method of fixation allowing immediate mobilisation for this group of patients.

  13. Primary desmoplastic small round cell tumor of the femur

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Akihiko; Garcia, Joaquin [Memorial Sloan-Kettering Cancer Center, Department of Pathology, New York, NY (United States); Edgar, Mark A. [Memorial Sloan-Kettering Cancer Center, Department of Pathology, New York, NY (United States); Weill Medical College of Cornell University, New York, NY (United States); Meyers, Paul A. [Weill Medical College of Cornell University, New York, NY (United States); Memorial Sloan-Kettering Cancer Center, Department of Pediatrics, New York, NY (United States); Morris, Carol D. [Weill Medical College of Cornell University, New York, NY (United States); Memorial Sloan-Kettering Cancer Center, Department of Surgery, Orthopaedic Service, New York, NY (United States); Panicek, David M. [Weill Medical College of Cornell University, New York, NY (United States); Memorial Sloan-Kettering Cancer Center, Department of Radiology, New York, NY (United States)

    2008-09-15

    Desmoplastic small round cell tumor (DSRCT) is a rare malignant neoplasm typically involving the abdominal cavity of a young male. Extra-abdominal occurrence of this tumor is very rare. We report a 10-year-old girl with primary DSRCT arising within the left femur. The patient presented with knee pain, and radiological findings were strongly suggestive of osteogenic sarcoma. In addition to the typical microscopic appearance and immunophenotype, RT-PCR demonstrated the chimeric transcript of EWS-WT1, which is diagnostic of DSRCT. Pulmonary metastases were present at initial staging studies, but no abdominal or pelvic lesion was present. Despite chemotherapy and complete tumor excision, the patient developed progressive lung and bone metastases and died 3 years after initial presentation. This is the second reported case of primary DSRCT of bone with genetic confirmation. (orig.)

  14. Stress Analysis of Human Femur under Different Loadings

    Science.gov (United States)

    Aghili, A. Latif; Hojjati, M. H.; Goudarzi, A. Moazemi; Rabiee, M.

    2011-12-01

    Stress fracture is a type of biomechanical failure of bone caused by loads during intense physical training. This failure is very important for aged persons and athletics. Because of cell death, in some cases after emergency surgery the injured person may suffer from lifelong disability. In this research, a three-dimensional finite element model of human femur has been created and analyzed under single, expanded and partial expanded loads. Analysis has been performed using commercially available software. The material is assumed to have isotropic elastic characteristics. The results indicated that the maximum stress occurred at the inferior root of the femoral neck. The magnitude of the strain shows good agreement with the published experimental results. This verifies the finite element modeling and the simplified model used.

  15. Foetal biometry in polyhydramnios: Does femur length fall behind?

    Science.gov (United States)

    Ipek, Ali; Idilman, Ilkay S; Kurt, Aydın; Cay, Nurdan; Unal, Ozlem; Erdogan, Beyza Doganay; Keskin, Huseyin Levent; Arslan, Halil

    2016-01-01

    We aimed to identify the growth patterns in polyhydramnios, and therefore evaluated 108 singleton pregnancies complicated with polyhydramnios according to the changes in biparietal diameter (BPD), abdominal circumference (AC) and femur length (FL) percentiles. The pregnancy outcomes according to the growth features were analysed. In the study population, BPD and AC percentiles exhibited a significant increase (p = 0.023 and 0.05, respectively), although FL percentiles showed a significant decrease (p = 0.006) according to the changes in third trimester relative to second trimester. In the overgrown group (n = 52), the FL/BPD ratio was lower (p polyhydramnios. However, we observed a shorter FL and a lower FL/BPD ratio without associated skeletal dysplasia in overgrown foetuses.

  16. Components of Geometric Analogy Solution.

    Science.gov (United States)

    Mulholland, Timothy M.; And Others

    1980-01-01

    Adults' geometric analogy solution was investigated as a function of systematic variations in the information structure of items. Latency data from verification of true and false items were recorded. A model incorporating assumptions about the form of item representation, working memory factors, and processing components and strategies was…

  17. Celestial mechanics with geometric algebra

    Science.gov (United States)

    Hestenes, D.

    1983-01-01

    Geometric algebra is introduced as a general tool for Celestial Mechanics. A general method for handling finite rotations and rotational kinematics is presented. The constants of Kepler motion are derived and manipulated in a new way. A new spinor formulation of perturbation theory is developed.

  18. Vergence, Vision, and Geometric Optics

    Science.gov (United States)

    Keating, Michael P.

    1975-01-01

    Provides a definition of vergence in terms of the curvature of the wave fronts, and gives examples to illustrate the advantages of this approach. The vergence treatment of geometrical optics provides both conceptual and algebraic advantages, particularly for the life science student, over the traditional object distance-image distance-focal length…

  19. Experimentally accessible geometrical separability criteria

    Energy Technology Data Exchange (ETDEWEB)

    Badziag, Piotr [Alba Nova Fysikum, University of Stockholm, S-106 91 Stockholm (Sweden); Brukner, Caslav; Paterek, Tomasz [Institute for Quantum Optics and Quantum Information, Austrian Academy of Sciences, Boltzmanngasse 3, A-1090 Vienna (Austria); Laskowski, Wieslaw; Zukowski, Marek [Institute of Theoretical Physics and Astrophysics, University of Gdansk, ul.Wita Stwosza 57, PL-80-952 Gdansk (Poland)], E-mail: wieslaw.laskowski@univ.gda.pl

    2009-07-15

    We present an intuitive geometrical approach to entanglement detection. It allows one to formulate simple and experimentally feasible sufficient conditions for entanglement. Within the approach we derive the necessary and sufficient condition for separability and discuss its relation with entanglement witnesses and positive maps.

  20. Metastable vacua and geometric deformations

    CERN Document Server

    Amariti, A; Girardello, L; Mariotti, A

    2008-01-01

    We study the geometric interpretation of metastable vacua for systems of D3 branes at non isolated toric deformable singularities. Using the L^{aba} examples, we investigate the relations between the field theoretic susy breaking and restoration and the complex deformations of the CY singularities.

  1. Is clinical measurement of anatomic axis of the femur adequate?

    Science.gov (United States)

    Wu, Chi-Chuan

    2017-08-01

    Background and purpose - The accuracy of using clinical measurement from the anterior superior iliac spine (ASIS) to the center of the knee to determine an anatomic axis of the femur has rarely been studied. A radiographic technique with a full-length standing scanogram (FLSS) was used to assess the adequacy of the clinical measurement. Patients and methods - 100 consecutive young adult patients (mean age 34 (20-40) years) with chronic unilateral lower extremity injuries were studied. The pelvis and intact contralateral lower extremity images in the FLSS were selected for study. The angles between the tibial axis and the femoral shaft anatomic axis (S-AA), the piriformis anatomic axis (P-AA), the clinical anatomic axis (C-AA), and the mechanical axis (MA) were compared between sexes. Results - Only the S-AA and C-AA angles were statistically significantly different in the 100 patients (3.6° vs. 2.8°; p = 0.03). There was a strong correlation between S-AA, P-AA, and C-AA angles (r > 0.9). The average intersecting angle between MA and S-AA in the femur in the 100 patients was 5.5°, and it was 4.8° between MA and C-AA. Interpretation - Clinical measurement of an anatomic axis from the ASIS to the center of the knee may be an adequate and acceptable method to determine lower extremity alignment. The optimal inlet for antegrade femoral intramedullary nailing may be the lateral edge of the piriformis fossa.

  2. Semi-automatic segmentation of femur based on harmonic barrier.

    Science.gov (United States)

    Zou, Zheng; Liao, Sheng-Hui; Luo, San-Ding; Liu, Qing; Liu, Shi-Jian

    2017-05-01

    Segmentation of the femur from the hip joint in computed tomography (CT) is an important preliminary step in hip surgery planning and simulation. However, this is a time-consuming and challenging task due to the weak boundary, the varying topology of the hip joint, and the extremely narrow or blurred space between the femoral head and the acetabulum. To address these problems, this study proposed a semi-automatic segmentation framework based on harmonic fields for accurate segmentation. The proposed method comprises three steps. First, with high-level information provided by the user, shape information provided by neighboring slices as well as the statistical information in the mask, a region selection method is proposed to effectively locate joint space for the harmonic field. Second, incorporated with an improved gradient, the harmonic field is used to adaptively extract a curve as the barrier that separates the femoral head from the acetabulum accurately. Third, a divide and conquer segmentation strategy based on the harmonic barrier is used to combine the femoral head part and body part as the final segmentation result. We have tested 40 hips with considerately narrow or disappeared joint spaces. The experimental results are evaluated based on Jaccard, Dice, directional cut discrepancy (DCD) and receiver operating characteristic (ROC), and we achieve the higher Jaccard of 84.02%, Dice of 85.96%, area under curve (AUC) of 89.3%, and the lower error with DCD of 0.52mm. The effective ratio of our method is 79.1% even for cases with severe malformation. The results show that our method performs best in terms of effectiveness and accuracy on the whole data set. The proposed method is efficient to segment femurs with narrow joint space. The accurate segmentation results can assist the physicians for osteoarthritis diagnosis in future. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Widening of the femoral proximal diaphysis--metaphysis angle in fetuses with achondroplasia.

    Science.gov (United States)

    Khalil, A; Morales-Roselló, J; Morlando, M; Bhide, A; Papageorghiou, A; Thilaganathan, B

    2014-07-01

    It has recently been reported that fetuses with achondroplasia have a wider than expected femoral proximal diaphysis-metaphysis angle (femoral angle). The aim of this case-control study was to investigate this finding. Cases with confirmed achondroplasia (n = 6), small-for-gestational-age fetuses (n = 70) and a group of normal fetuses (n = 377) were included in this study. The ultrasound image of the femur was examined by two independent experienced observers blinded to the diagnosis, who measured the femoral angle. These values were converted into multiples of the expected median (MoM), after adjustment for gestational age and femur length. Prevalence of various prenatal ultrasound signs of achondroplasia was determined in affected fetuses. Intra- and interobserver agreement of measurement of femoral angle was assessed using 95% limits of agreement and kappa statistics. The femoral angle can be measured accurately by ultrasound, and increases with both increasing gestational age and increasing femur length. The femoral angle-MoM was significantly higher in fetuses with achondroplasia than in the control group (1.36 vs 1.00 MoM, P achondroplasia (83.3%), which was the most consistent finding other than shortening of the long bones. The femoral angle is wider in fetuses with achondroplasia. This new ultrasound sign appears promising as an additional discriminatory marker when clinicians are faced with a case of short long bones in the third trimester. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

  4. [Effect of intramedullary reaming and nailing on the production of growth factors in the femur fracture callus in rats].

    Science.gov (United States)

    Mingo-Robinet, J; Valle-Cruz, J A; Ortega-Medina, L; Fuentes-Ferrer, M; López-Durán Stern, L

    2013-01-01

    Many studies have been conducted to determine the different effects that reaming or intramedullary nailing have on fracture healing, but there is no evidence in the literature of the effect of intramedullary reaming on osteogenesis. We performed a prospective study to analyse the effect of intramedullary reaming and nailing on the production of growth factors during the process of fracture healing in the femur of rats. A transverse mid-shaft non-comminuted femur fracture was produced in 64 rats; 34 rats did not receive any treatment, and a standardized surgical procedure was performed on 30 rats, by exposing the left knee, reaming the medullary canal from distal to proximal, and then fixing the fracture with a steel pin. The rats were sacrificed at the 24th hour, 4th, 7th and 15th days after the fracture. The amount of growth factors that appeared in the callus fracture was measured using histopathology studies. The primary categorical variables analysed were PDGFA, TGF2 and TGFβ-R2. These variables were analysed in each group at the different sacrifice times. The results of the primary variables of the study, stratified by the time until sacrifice, showed no statistically significant differences. Even if the presence of an intramedullary wire facilitates the fracture repair and the stabilising the bridge of bone between both edges of the fracture site, no evidence was found that reaming changes the expression of the growth factors studied (PDGFA, TGFβ-R2 and TGFβ2) during the callus formation in rats. © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  5. Geometric comparison of popular mixture-model distances.

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Scott A.

    2010-09-01

    Statistical Latent Dirichlet Analysis produces mixture model data that are geometrically equivalent to points lying on a regular simplex in moderate to high dimensions. Numerous other statistical models and techniques also produce data in this geometric category, even though the meaning of the axes and coordinate values differs significantly. A distance function is used to further analyze these points, for example to cluster them. Several different distance functions are popular amongst statisticians; which distance function is chosen is usually driven by the historical preference of the application domain, information-theoretic considerations, or by the desirability of the clustering results. Relatively little consideration is usually given to how distance functions geometrically transform data, or the distances algebraic properties. Here we take a look at these issues, in the hope of providing complementary insight and inspiring further geometric thought. Several popular distances, {chi}{sup 2}, Jensen - Shannon divergence, and the square of the Hellinger distance, are shown to be nearly equivalent; in terms of functional forms after transformations, factorizations, and series expansions; and in terms of the shape and proximity of constant-value contours. This is somewhat surprising given that their original functional forms look quite different. Cosine similarity is the square of the Euclidean distance, and a similar geometric relationship is shown with Hellinger and another cosine. We suggest a geodesic variation of Hellinger. The square-root projection that arises in Hellinger distance is briefly compared to standard normalization for Euclidean distance. We include detailed derivations of some ratio and difference bounds for illustrative purposes. We provide some constructions that nearly achieve the worst-case ratios, relevant for contours.

  6. Fractures of the proximal humerus

    DEFF Research Database (Denmark)

    Brorson, Stig

    2013-01-01

    . The bandages were further supported by splints made of wood or coarse grass. Healing was expected in forty days. Different fracture patterns have been discussed and classified since Ancient Greece. Current classification of proximal humeral fractures mainly relies on the classifications proposed by Charles......, classification of proximal humeral fractures remains a challenge for the conduct, reporting, and interpretation of clinical trials. The evidence for the benefits of surgery in complex fractures of the proximal humerus is weak. In three systematic reviews I studied the outcome after locking plate osteosynthesis......Fractures of the proximal humerus have been diagnosed and managed since the earliest known surgical texts. For more than four millennia the preferred treatment was forceful traction, closed reduction, and immobilization with linen soaked in combinations of oil, honey, alum, wine, or cerate...

  7. Translational Imaging Spectroscopy for Proximal Sensing.

    Science.gov (United States)

    Rogass, Christian; Koerting, Friederike M; Mielke, Christian; Brell, Maximilian; Boesche, Nina K; Bade, Maria; Hohmann, Christian

    2017-08-11

    Proximal sensing as the near field counterpart of remote sensing offers a broad variety of applications. Imaging spectroscopy in general and translational laboratory imaging spectroscopy in particular can be utilized for a variety of different research topics. Geoscientific applications require a precise pre-processing of hyperspectral data cubes to retrieve at-surface reflectance in order to conduct spectral feature-based comparison of unknown sample spectra to known library spectra. A new pre-processing chain called GeoMAP-Trans for at-surface reflectance retrieval is proposed here as an analogue to other algorithms published by the team of authors. It consists of a radiometric, a geometric and a spectral module. Each module consists of several processing steps that are described in detail. The processing chain was adapted to the broadly used HySPEX VNIR/SWIR imaging spectrometer system and tested using geological mineral samples. The performance was subjectively and objectively evaluated using standard artificial image quality metrics and comparative measurements of mineral and Lambertian diffuser standards with standard field and laboratory spectrometers. The proposed algorithm provides highly qualitative results, offers broad applicability through its generic design and might be the first one of its kind to be published. A high radiometric accuracy is achieved by the incorporation of the Reduction of Miscalibration Effects (ROME) framework. The geometric accuracy is higher than 1 μpixel. The critical spectral accuracy was relatively estimated by comparing spectra of standard field spectrometers to those from HySPEX for a Lambertian diffuser. The achieved spectral accuracy is better than 0.02% for the full spectrum and better than 98% for the absorption features. It was empirically shown that point and imaging spectrometers provide different results for non-Lambertian samples due to their different sensing principles, adjacency scattering impacts on the signal

  8. The infrastructure of psychological proximity

    DEFF Research Database (Denmark)

    Nickelsen, Niels Christian Mossfeldt

    2015-01-01

    ). The experience of psychological proximity between patient and nurse is provided through confidence, continuity and the practical set-up. This constitutes an important enactment of skillfulness, which may render telemedicine a convincing health service in the future. Methodology: The study draws on a pilot...... (Langstrup & Winthereik 2008). This study contributes by showing the infrastructure of psychological proximity, which is provided by way of device, confidence, continuity and accountability....

  9. Three-Dimensional Analysis of the Curvature of the Femoral Canal in 426 Chinese Femurs

    Directory of Open Access Journals (Sweden)

    Xiu-Yun Su

    2015-01-01

    Full Text Available Purpose. The human femur has long been considered to have an anatomical anterior curvature in the sagittal plane. We established a new method to evaluate the femoral curvature in three-dimensional (3D space and reveal its influencing factors in Chinese population. Methods. 3D models of 426 femurs and the medullary canal were constructed using Mimics software. We standardized the positions of all femurs using 3ds Max software. After measuring the anatomical parameters, including the radius of femoral curvature (RFC and banking angle, of the femurs using the established femur-specific coordinate system, we analyzed and determined the relationships between the anatomical parameters of the femur and the general characteristics of the population. Results. Pearson’s correlation analyses showed that there were positive correlations between the RFC and height (r=0.339, p<0.001 and the femoral length and RFC (r=0.369, p<0.001 and a negative correlation between the femoral length and banking angle (r=-0.223, p<0.001. Stepwise linear regression analyses showed that the most relevant factors for the RFC and banking angle were the femoral length and gender, respectively. Conclusions. This study concluded that the banking angle of the femur was significantly larger in female than in male.

  10. Ossification of the femur and tibia of the post-hatching Japanese quail.

    Science.gov (United States)

    Ahmed, Yasser A; Soliman, Soha A; Abdel-Hafez, Enas A

    2013-09-01

    The current study aimed to describe the histological changes of the femur and tibia of the post-hatching quail. Femur and tibia from 1-day- to 6-weeks post-hatching quail were processed for light microscopy. Histological examination revealed that endochondral ossification was a delayed process in the development of femur and tibia preceded by periosteal ossification. Femur and tibia of 1-day-post-hatching quail consisted of growth cartilage enclosed in a tube of periosteal bone collar. The collar extended toward the epiphysis dividing it into articular cartilage proper and lateral articular cartilage. Down to the articular cartilage, there was a physeal growth cartilage, in which the chondrocytes were organized into resting, proliferative and hypertrophic zones. Focal areas of hypertrophic chondrocytes were observed in the epiphysis of the tibia but not of the femur, which acted as a nidus for formation of the secondary ossification centre after in 2-week-posthathcing quail. Primary ossification centre was seen in both femur and tibia after 2 weeks and ossification continued replacing the cartilage until the 6th week when only permanent articular cartilage remained. Cartilage canals were present in both femur and tibia starting from the day 1, but chondrified and completely disappeared after the 6th week. The current study suggests that the periosteal ossification preceded the endochondral ossification and plays an important role in quail long bones development.

  11. The accuracy of gestational age predicted from femur and humerus length in Saanen goats using ultrasonography

    Directory of Open Access Journals (Sweden)

    Mohamed Abdelghafar Rihab

    2012-01-01

    Full Text Available Serial transabdominal ultrasonographic scanning was performed to measure femur and humerus length of foetuses of Saanen goats to establish their gestational stage. Data were obtained from 38 goats that became pregnant after artificial insemination. Animals were restrained in a supine position on a special table designed for this purpose. Humerus and femur length were measured at weekly intervals starting from week 8 of gestation till the end of gestation. Real-time ultrasound scanner equipped with switchable frequency (5-7.5 MHz micro convex probe was used in the present study. Humerus and femur length showed strong positive correlation with gestational age (r2 = 0.95. Measurements of humerus and femur of foetuses are useful indicators to predict gestational age at the 2nd and 3rd trimesters in Saanen goats. Measuring of only one bone length is quite enough. Incorporating of both measurements within a multiple regression equation did not improve predictive capacity of the bones. The results of the study were used to construct reference charts and gestational equations in Saanen goats utilizing humerus and femur measurements. In Sudan, this is the first study utilizing measurements of the femur and humerus and the first study comparing the length of the humerus and femur for predicting gestational age in Saanen goats.

  12. Effect of triple pelvic osteotomy on the proximal femoral geometry in dysplastic dogs.

    Science.gov (United States)

    Sarierler, Murat; Yildirim, Ismail Gokce; Ocal, Mehmet Kamil

    2012-02-01

    Triple pelvic osteotomy (TPO) is one of the surgical procedures for use to try to reduce subsequent degenerative joint disease or modify the progress of hip dysplasia in young dogs. Joint force and pressure distribution were changed by this procedure. Therefore, the aim of this study was to find out whether the remodeling of proximal femur exists or not after TPO in dysplastic dogs. Ten femora from five young dysplastic mongrel dogs, treated unilaterally with TPO using 20° canine pelvic osteotomy plates, were used. One year after TPO, neck-proximal shaft angle, femoral head, neck, diaphyseal and mid-shaft diameters, total femoral, femoral neck axis, and intertrochanteric, femoral head offset lengths as well as the lengths from head center to lateral margin of greater trochanter and to proximal femoral axis were measured from the bone. The significant differences between treatment and control side were determined in Norberg angle, neck-proximal shaft angle, neck diameter, diaphyseal diameter, mid-shaft diameter, length from head center to proximal femoral axis and femoral head offset length. In conclusion, although small number of cases was used, it was determined that the aforementioned variables are affected by TPO. So, these variables may be supply additional information about the changes to the joint following TPO in dysplastic dogs. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Efficiency of the Lausanne clinical pathway for proximal femoral fractures

    Directory of Open Access Journals (Sweden)

    Nicole eFleury

    2015-02-01

    Full Text Available Purpose/Introduction: The number of hip fractures is rising, due to increases in life expectancy. In such cases patients are at risk from post-operative complications and subsequently the average length of hospitalisation may be extended. In 2011, we established a clinical pathway (CP, a specific model of care for patient-care management, to improve the clinical and economic outcomes of proximal femoral fracture management in elderly patients. The goal was to evaluate the CP using clinical, process and financial indicators.Methods: We included all surgical patients aged 65 and over, admitted to the emergency department with a fracture of the proximal femur following a fall. Assessment parameters included three performance indicators: clinical, process and financial. The clinical indicators were the presence or absence of acute delirium on the third post-operative day, diagnosis of nosocomial pneumonia, and the number of patients fulfilling at least 75% of their nutritional requirements at the end of the hospitalisation period. The process indicator was the time interval between arrival at the emergency department and surgery. The financial indicator was based on the number of days spent in hospital.Results: From 2011 to 2013, 669 patients were included in the CP. We observed that the average length of stay in hospital decreased as soon as the CP was implemented and stabilised afterwards. The goal of 90% of patients undergoing surgery within 48 hours of arrival in the emergency department was surpassed in 2013 (93.1%. Furthermore, we observed an improvement in the clinical indicators. Conclusions: The application of a CP allowed an improvement in the qualitative and quantitative efficiency of proximal femoral fracture management in elderly patients, in terms of clinical, process and financial factors.

  14. Biomechanical comparison of a 3.5-mm conical coupling plating system and a 3.5-mm locking compression plate applied as plate-rod constructs to an experimentally created fracture gap in femurs of canine cadavers.

    Science.gov (United States)

    Tremolada, Giovanni; Lewis, Daniel D; Paragnani, Ken Luka; Conrad, Bryan P; Kim, Stanley E; Pozzi, Antonio

    2017-06-01

    OBJECTIVE To compare stiffness and resistance to cyclic fatigue of two 3.5-mm locking system plate-rod constructs applied to an experimentally created fracture gap in femurs of canine cadavers. SAMPLE 20 femurs from cadavers of 10 mixed-breed adult dogs. PROCEDURES 1 femur from each cadaver was stabilized with a conical coupling plating system-rod construct, and the contralateral femur was stabilized with a locking compression plate (LCP)-rod construct. An intramedullary Steinmann pin was inserted in each femur. A 40-mm gap then was created; the gap was centered beneath the central portion of each plate. Cyclic axial loading with increasing loads was performed. Specimens that did not fail during cyclic loading were subjected to an acute load to failure. RESULTS During cyclic loading, significantly more LCP constructs failed (6/10), compared with the number of conical coupling plating system constructs that failed (1/10). Mode of failure of the constructs included fracture of the medial or caudal aspect of the cortex of the proximal segment with bending of the plate and pin, bending of the plate and pin without fracture, and screw pullout. Mean stiffness, yield load, and load to failure were not significantly different between the 2 methods of stabilization. CONCLUSIONS AND CLINICAL RELEVANCE Both constructs had similar biomechanical properties, but the conical coupling plating system was less likely to fail than was the LCP system when subjected to cyclic loading. These results should be interpreted with caution because testing was limited to a single loading mode.

  15. Prevalence of abuse among young children with femur fractures: a systematic review.

    Science.gov (United States)

    Wood, Joanne N; Fakeye, Oludolapo; Mondestin, Valerie; Rubin, David M; Localio, Russell; Feudtner, Chris

    2014-07-02

    Clinical factors that affect the likelihood of abuse in children with femur fractures have not been well elucidated. Consequently, specifying which children with femur fractures warrant an abuse evaluation is difficult. Therefore the purpose of this study is to estimate the proportion of femur fractures in young children attributable to abuse and to identify demographic, injury and presentation characteristics that affect the probability that femur fractures are secondary to abuse. We conducted a systematic review of published articles written in English between January 1990 and July 2013 on femur fracture etiology in children less than or equal to 5 years old based on searches in PubMed/MEDLINE and CINAHL databases. Data extraction was based on pre-defined data elements and included study quality indicators. A meta-analysis was not performed due to study population heterogeneity. Across the 24 studies reviewed, there were a total of 10,717 children less than or equal to 60 months old with femur fractures. Among children less than 12 months old with all types of femur fractures, investigators found abuse rates ranging from 16.7% to 35.2%. Among children 12 months old or greater with femur fractures, abuse rates were lower: from 1.5% - 6.0%. In multiple studies, age less than 12 months, non-ambulatory status, a suspicious history, and the presence of additional injuries were associated with findings of abuse. Diaphyseal fractures were associated with a lower abuse incidence in multiple studies. Fracture side and spiral fracture type, however, were not associated with abuse. Studies commonly find a high proportion of abuse among children less than 12 months old with femur fractures. The reported trauma history, physical examination findings and radiologic results must be examined for characteristics that increase or decrease the likelihood of abuse determination.

  16. Femur Fractures in Parkinsonism: Analysis of a National Sample Cohort in South Korea

    Science.gov (United States)

    An, Soo Jeong; Lee, Seo-Young; Kwon, Jae-Woo; Lee, Seung-Joon; Kim, Young-Ju

    2017-01-01

    Background and Purpose Falling with a femur fracture is a serious event that negatively affects the quality of life of elderly individuals as well as patients with parkinsonism. This study investigated the association between parkinsonism and femur fracture and compared the risk of femur fracture between subjects with and without parkinsonism. Methods This study examined a population-based matched cohort constructed using the National Sample Cohort data set, which comprises approximately one million subscribers to medical insurance and aid in South Korea. Subjects with parkinsonism during 2003–2013 were identified as the exposed group, and up to five individuals matched for age, sex, and index years were identified as the controls for each parkinsonism subject. The risk of femur fracture for parkinsonism was evaluated using Cox regression. Results The incidence of femur fracture according to age, sex, and body mass index varied significantly between subjects with parkinsonism and controls (pfemur fractures for males [hazard ratio (HR)=2.85, 95% confidence interval [CI]=1.87–4.34], subjects younger than 65 years (HR=2.89, 95% CI=1.64–5.11), and underweight subjects (HR=3.90, 95% CI=1.82–8.35). The adjusted HR for femur fracture with parkinsonism was highest within 2 years of the disease diagnosis (HR=3.10, 95% CI=2.12–4.53). Conclusions Our study found that the presence of parkinsonism is more strongly related to femur fracture in males, and increases the influence of traditional risk factors on femur fracture. It is necessary to consider how factors associated with the amount of ambulatory activity–even in an early diagnosed state–can play an important role in femur fracture in subjects with parkinsonism. PMID:29057630

  17. Prevalence of abuse among young children with femur fractures: a systematic review

    Science.gov (United States)

    2014-01-01

    Background Clinical factors that affect the likelihood of abuse in children with femur fractures have not been well elucidated. Consequently, specifying which children with femur fractures warrant an abuse evaluation is difficult. Therefore the purpose of this study is to estimate the proportion of femur fractures in young children attributable to abuse and to identify demographic, injury and presentation characteristics that affect the probability that femur fractures are secondary to abuse. Methods We conducted a systematic review of published articles written in English between January 1990 and July 2013 on femur fracture etiology in children less than or equal to 5 years old based on searches in PubMed/MEDLINE and CINAHL databases. Data extraction was based on pre-defined data elements and included study quality indicators. A meta-analysis was not performed due to study population heterogeneity. Results Across the 24 studies reviewed, there were a total of 10,717 children less than or equal to 60 months old with femur fractures. Among children less than 12 months old with all types of femur fractures, investigators found abuse rates ranging from 16.7% to 35.2%. Among children 12 months old or greater with femur fractures, abuse rates were lower: from 1.5% - 6.0%. In multiple studies, age less than 12 months, non-ambulatory status, a suspicious history, and the presence of additional injuries were associated with findings of abuse. Diaphyseal fractures were associated with a lower abuse incidence in multiple studies. Fracture side and spiral fracture type, however, were not associated with abuse. Conclusions Studies commonly find a high proportion of abuse among children less than 12 months old with femur fractures. The reported trauma history, physical examination findings and radiologic results must be examined for characteristics that increase or decrease the likelihood of abuse determination. PMID:24989500

  18. Height and Tilt Geometric Texture

    DEFF Research Database (Denmark)

    Andersen, Vedrana; Desbrun, Mathieu; Bærentzen, Jakob Andreas

    2009-01-01

    We propose a new intrinsic representation of geometric texture over triangle meshes. Our approach extends the conventional height field texture representation by incorporating displacements in the tangential plane in the form of a normal tilt. This texture representation offers a good practical...... compromise between functionality and simplicity: it can efficiently handle and process geometric texture too complex to be represented as a height field, without having recourse to full blown mesh editing algorithms. The height-and-tilt representation proposed here is fully intrinsic to the mesh, making...... texture editing and animation (such as bending or waving) intuitively controllable over arbitrary base mesh. We also provide simple methods for texture extraction and transfer using our height-and-field representation....

  19. On chromatic and geometrical calibration

    DEFF Research Database (Denmark)

    Folm-Hansen, Jørgen

    1999-01-01

    The main subject of the present thesis is different methods for the geometrical and chromatic calibration of cameras in various environments. For the monochromatic issues of the calibration we present the acquisition of monochrome images, the classic monochrome aberrations and the various sources...... to design calibration targets for both geometrical and chromatic calibration are described. We present some possible systematical errors on the detection of the objects in the calibration targets, if viewed in a non orthogonal angle, if the intensities are uneven or if the image blurring is uneven. Finally...... of non-uniformity of the illumination of the image plane. Only the image deforming aberrations and the non-uniformity of illumination are included in the calibration models. The topics of the pinhole camera model and the extension to the Direct Linear Transform (DLT) are described. It is shown how...

  20. Geometrical interpretation of optical absorption

    Energy Technology Data Exchange (ETDEWEB)

    Monzon, J. J.; Barriuso, A. G.; Sanchez-Soto, L. L. [Departamento de Optica, Facultad de Fisica, Universidad Complutense, E-28040 Madrid (Spain); Montesinos-Amilibia, J. M. [Departamento de Geometria y Topologia, Facultad de Matematicas, Universidad Complutense, E-28040 Madrid (Spain)

    2011-08-15

    We reinterpret the transfer matrix for an absorbing system in very simple geometrical terms. In appropriate variables, the system appears as performing a Lorentz transformation in a (1 + 3)-dimensional space. Using homogeneous coordinates, we map that action on the unit sphere, which is at the realm of the Klein model of hyperbolic geometry. The effects of absorption appear then as a loxodromic transformation, that is, a rhumb line crossing all the meridians at the same angle.

  1. Science, Art and Geometrical Imagination

    OpenAIRE

    Luminet, J. -P.

    2009-01-01

    From the geocentric, closed world model of Antiquity to the wraparound universe models of relativistic cosmology, the parallel history of space representations in science and art illustrates the fundamental role of geometric imagination in innovative findings. Through the analysis of works of various artists and scientists like Plato, Durer, Kepler, Escher, Grisey or the present author, it is shown how the process of creation in science and in the arts rests on aesthetical principles such as ...

  2. On chromatic and geometrical calibration

    OpenAIRE

    Folm-Hansen, Jørgen

    1999-01-01

    The main subject of the present thesis is different methods for the geometrical and chromatic calibration of cameras in various environments. For the monochromatic issues of the calibration we present the acquisition of monochrome images, the classic monochrome aberrations and the various sources of non-uniformity of the illumination of the image plane. Only the image deforming aberrations and the non-uniformity of illumination are included in the calibration models. The topics of the pinhole...

  3. Geometrical Aspects of Venus Transit

    CERN Document Server

    Bertuola, Alberto C; Magalhães, N S; Filho, Victo S

    2016-01-01

    We obtained two astronomical values, the Earth-Venus distance and Venus diameter, by means of a geometrical treatment of photos taken of Venus transit in June of 2012. Here we presented the static and translational modelsthat were elaborated taking into account the Earth and Venus orbital movements. An additional correction was also added by considering the Earth rotation movement. The results obtained were compared with the values of reference from literature, showing very good concordance.

  4. Geometrical quantization in Fock space

    CERN Document Server

    Maslov, V P

    1995-01-01

    We investigate an infinite dimensional analog of the theory of Lagrangian manifolds with complex germs. To such a manifold we assign a canonical operator that depends on creation and annihilation operators. This operator is by definition the geometrical quantization for these isotropic manifolds with complex germs. We prove that for secondary quantized equations this quantization is the asymptotics for the Cauchy problem. Results of Berezin are used thouroughly in the construction of the canonical operator and in proofs of the theorems.

  5. [Total hip replacement in elderly and senile patients with initial femur neck fractures].

    Science.gov (United States)

    Ternovoĭ, N K; Samokhin, A V; Grebennikov, K A

    2003-12-01

    We carried out researches with the purpose of comparison of operative treatment results of femur neck fractures in elderly and senile patients with those in other countries. Total hip replacement technique was used over the period of 1991-2002 yy. for 123 patients with femur neck fractures. We have used "Smith & Nephews" or "Zimmer" prostheses with "Polacos" or "Osteobond" acrylcements. Surgical approach tactics is very important for prophylaxis of early and late postoperative complications. Active and of sound mind patients with femur neck fractures should undergo total hip replacement procedure. Rehabilitation is also an important factor in preventive early and late postoperative complications.

  6. Compartment syndrome of the thigh complicating surgical treatment of ipsilateral femur and ankle fractures

    Science.gov (United States)

    Moore, M. R.; Garfin, S. R.; Hargens, A. R.

    1987-01-01

    A 26-year-old man presented with ipsilateral femur and ankle fractures. The patient was treated with interlocking nail of his femur fracture, followed by open reduction and internal fixation of his ankle fracture under tourniquet control. Postoperatively, the patient developed compartment syndrome of his thigh with elevated pressures, requiring decompressive fasciotomies. This case illustrates the possible complication of treating a femur fracture with intramedullary nailing and then immediately applying a tourniquet to treat an ipsilateral extremity fracture. Because of the complication with this patient, we feel the procedure should be staged, or a tourniquet should be avoided if possible.

  7. Riemannian geometry and geometric analysis

    CERN Document Server

    Jost, Jürgen

    2017-01-01

    This established reference work continues to provide its readers with a gateway to some of the most interesting developments in contemporary geometry. It offers insight into a wide range of topics, including fundamental concepts of Riemannian geometry, such as geodesics, connections and curvature; the basic models and tools of geometric analysis, such as harmonic functions, forms, mappings, eigenvalues, the Dirac operator and the heat flow method; as well as the most important variational principles of theoretical physics, such as Yang-Mills, Ginzburg-Landau or the nonlinear sigma model of quantum field theory. The present volume connects all these topics in a systematic geometric framework. At the same time, it equips the reader with the working tools of the field and enables her or him to delve into geometric research.  The 7th edition has been systematically reorganized and updated. Almost no page has been left unchanged. It also includes new material, for instance on symplectic geometry, as well as the B...

  8. Geometric Tachyon and Warm Inflation

    Science.gov (United States)

    Bhattacharjee, Anindita; Deshamukhya, Atri

    2013-03-01

    The inflationary models developed in presence of a background radiation can be a solution to the reheating problem faced by common cold (isentropic) inflationary scenario. A D-brane system comprising of k Neuvo-Schwarz (NS) 5-branes with a transverse circle and BPS D3-branes with world volume parallel to the NS 5-branes, placed at a point on the transverse circle diametrically to NS 5-brane has a point of unstable equilibrium and the D3-brane has a geometric tachyonic mode associated with displacement of the brane along the circle. Cold inflationary scenario has been studied in connection with this geometric tachyon [S. Panda, M. Sami and S. Tsujikawa, Phys. Rev. D73, 023515 (2006)] where it was found that one needs a background of minimum 104 branes to realize a viable inflationary model. In this piece of work, we have tried to study a model of inflation driven by this geometric tachyon in presence of radiation. We have found that compared to the isentropic scenario, to satisfy the observational bounds, the number of background branes required in this case reduces drastically and a viable model can be obtained with even six to seven NS 5-branes in the background. In this context, we have also analyzed the non-gaussianity associated with the model and observed that the concerned parameter lies well within the observation limit.

  9. Thrust plate prosthesis for proximal femoral deformity: a series of 15 patients.

    Science.gov (United States)

    Karatosun, Vasfi; Unver, Bayram; Gültekin, Alper; Günal, Izge

    2010-01-01

    Patients with coxarthrosis and proximal femoral deformity experience problems with total hip arthroplasty. A custom-made prosthesis or a proximal osteotomy is required for such cases, and these also increase the rate of complications. The purpose of this study was to evaluate the results of the thrust plate prosthesis (TPP) in patients with deformity of the proximal femur. Fifteen patients (7 females, 8 males) with a mean age of 56.4 years (range 19-75 years) at the time of the surgery were included in the study. The etiology was traumatic coxarthrosis in 12, and nonunion of a femoral neck fracture with osteonecrosis of the femoral head in the remaining three. While the femoral component was a third-generation TPP in all patients, the acetabular component was a Protek expansion cup in 12, and a cementless standard cup in three patients. All operations were performed through a Hardinge approach. Patients were followed up for at least 3 years (range 36-116 months) and evaluated clinically with the Harris Hip Score. The mean preoperative Harris Hip Score increased from 51.2 (range 15-79) to 92.7 (range 60-100) at the latest assessment. In two cases, loosening of the femoral component was observed in zone 3, both 12 months postoperatively. One was replaced by an intramedullary prosthesis, and the other was asymptomatic. TPP is a good alternative for patients with malformations of the proximal femur. The use of TPP avoids technical difficulties and a custom-made prosthesis.

  10. Scaling of form and function in the xenarthran femur: a 100-fold increase in body mass is mitigated by repositioning of the third trochanter.

    Science.gov (United States)

    Milne, Nick; O'Higgins, Paul

    2012-09-07

    How animals cope with increases in body size is a key issue in biology. Here, we consider scaling of xenarthrans, particularly how femoral form and function varies to accommodate the size range between the 3 kg armadillo and its giant relative the 300 kg glyptodont. It has already been noted that femoral morphology differs between these animals and suggested that this reflects a novel adaptation to size increase in glyptodont. We test this idea by applying a finite element analysis of coronal plane forces to femoral models of these animals, simulating the stance phase in the hind limb; where the femur is subject to bending owing to longitudinal compressive as well as abduction loads on the greater trochanter. We use these models to examine the hypothesis that muscles attaching on the third trochanter (T3) can reduce this bending in the loaded femur and that the T3 forces are more effective at reducing bending in glyptodont where the T3 is situated at the level of the knee. The analysis uses traditional finite element methods to produce strain maps and examine strains at 200 points on the femur. The coordinates of these points before and after loading are also used to carry out geometric morphometric (GM) analyses of the gross deformation of the model in different loading scenarios. The results show that longitudinal compressive and abductor muscle loading increases bending in the coronal plane, and that loads applied to the T3 reduce that bending. In the glyptodont model, the T3 loads are more effective and can more readily compensate for the bending owing to longitudinal and abductor loads. This study also demonstrates the usefulness of GM methods in interpreting the results of finite element analyses.

  11. Proximal femoral physis shear in slipped capital femoral epiphysis--a finite element study.

    Science.gov (United States)

    Fishkin, Zair; Armstrong, Douglas G; Shah, Hardik; Patra, Abani; Mihalko, William M

    2006-01-01

    The following finite element study was conducted to determine whether increased body weight, femoral retroversion, and varus hip loading could sufficiently raise physeal shear strains and stresses above the yield point and predispose an adolescent hip to a slip. A computer tomography scan of a 13-year-old child with slipped capital femoral epiphysis was used to generate a solid model of the proximal femur and physis. The model was parameterized using 3-dimensional software to generate three difference angles of femoral neck version-neutral, 15 degrees retroversion, and 15 degrees anteversion. Loads of 2.7 times body weight in a 46- and 86-kg child were applied to the proximal femur to model stance on one leg. In addition, the loading vector was reoriented at various degrees of varus to study the effect of varus loading on physis shear. The results demonstrated that physis stress, strain, and displacement increased with greater body weight, retroversion, and varus displacement of the loading vector. Physis shear strain in hips with a combination of varus loading and femoral neck retroversion exceeded the reported ultimate strain values for cartilaginous soft tissues. The finite element models suggest that in an overweight child, the combination of retroversion and varus hip load may be sufficient to increase physeal strains above the yield point and result in a slip.

  12. Geometric Phase and Classical-Quantum Correspondence

    OpenAIRE

    Satija, Indubala I.; Balakrishnan, Radha

    2004-01-01

    We study the geometric phase factors underlying the classical and the corresponding quantum dynamics of a driven nonlinear oscillator exhibiting chaotic dynamics. For the classical problem, we compute the geometric phase factors associated with the phase space trajectories using Frenet-Serret formulation. For the corresponding quantum problem, the geometric phase associated with the time evolution of the wave function is computed. Our studies suggest that the classical geometric phase may be ...

  13. Geometrical Visualisation--Epistemic and Emotional

    Science.gov (United States)

    Rodd, Melissa

    2010-01-01

    A well-documented experience of students of elementary Euclidean geometry is "seeing" a geometric result and being sure about its truth; this sort of experience gives rise to the notion of geometrical visualisation that is developed here. In this essay a philosophical argument for the epistemic potential of geometrical visualisation is reviewed,…

  14. Design and Optimization of Sinusoidal Formed Femur Prosthesis

    Directory of Open Access Journals (Sweden)

    Ahmet Zafer ŞENALP

    2015-01-01

    Full Text Available One of the major problems in hip replacement surgery is the hip replacement loosening. Hip replacement loosening occurs over time after the surgery and it is related to the discretization between the bone cement and prosthesis. The underlying factors of this situation are the stress occurring in the bone cement and the shape of the prosthesis. In this study, cortical and trabecular layers of the femur, bone cement and prosthesis were modeled. The models of bone cement and prosthesis were constructed parametrically and two different sinusoidal formed prostheses were developed unlike the former prostheses shapes. Analyses were conducted for these two different sinusoidal forms by using finite element method and optimization was conducted to obtain the appropriate prosthesis stem shape and bone cement thickness by using parametric modeling in finite element analyses. For finite element analyses and optimization, Ansys Workbench software was used and analyses were conducted for 316LS stainless steel material. Finally, the optimum prosthesis stem shape and bone cement thickness was determined by using the results of the analyses in the first stage

  15. Total Femur Replacement After Tumor Resection: Limb Salvage Usually Achieved But Complications and Failures are Common.

    Science.gov (United States)

    Sevelda, Florian; Schuh, Reinhard; Hofstaetter, Jochen Gerhard; Schinhan, Martina; Windhager, Reinhard; Funovics, Philipp Theodor

    2015-06-01

    Primary bone or soft tissue tumors of the femur sometimes present with severe and extensive bone destruction, leaving few limb-salvage options other than total femur replacement. However, there are few data available regarding total femur replacement and, in particular, regarding implant failures. We asked: (1) What are the revision-free and overall implant survival rates of conventional total femur replacements in patients treated for sarcoma of the femur or soft tissues? (2) What are the revision-free and overall implant survival rates of expandable total femur replacements in skeletally immature patients? (3) Using the comprehensive International Society of Limb Salvage failure-mode classification, what types of complications occur with conventional and expandable total femur replacements? Our retrospective, single-center cohort study was based on data prospectively collected for 50 patients who received a total femur replacement after tumor resection for indications other than carcinoma or metastatic disease. Of the 50 patients, six (12%) were lost to followup before 6 months. Ten of the remaining 44 patients received expandable implants. The mean followup was 57 months (range, 1-280 months) and 172 months (range, 43-289 months) for patients who underwent conventional and expandable total femur replacements, respectively. For implant survival, competing risk analyses were used. At 5 years, revision-free implant survival of conventional total femur replacements was 48% (95% CI, 0.37-0.73), and overall implant survival was 97% (95% CI, 0.004-0.20). Five-year revision-free implant survival of expandable total femur replacements was 30% (95% CI, 0.47-1.00) and overall implant survival was 100%. With conventional total femur replacements soft tissue failures occurred in 13 of 34 patients, structural failures in three, infection in six, and local tumor progression in one. No patient had aseptic loosening with conventional total femur replacements, but hip

  16. Autologous grafts of double-strut fibular cortical bone plate to treat the fractures and defects of distal femur: a case report and review of literature

    Directory of Open Access Journals (Sweden)

    CHEN Xu

    2012-02-01

    Full Text Available 【Abstract】We reported a 23-year-old man who was involved in a high-speed motorcycle accident. He sustained a closed fracture at the right distal femur. The primary fracture happened on February 2008. He underwent open reduction and internal fixation with cloverleaf plate. And one hundred days after the surgery, the proximal screws were pulled-out, but the bone union was not achieved. Treatment consisted of exchanging the cloverleaf plate with a locking compression plate and using an auto-iliac bone graft to fill the nonunion gap. In July 2009, the patient had a sharp pain in the right lower limb. The X-ray revealed that the plate implanted last year was broken, causing a nonunion at the fracture site. Immediately the plate and screws were removed and an intramedullary nail was inserted reversely from the distal femur as well as a 7 cm long bone from the right fibula was extracted and longitudinally split into two pieces to construct cortical bone plates. Then we placed them laterally and medially to fracture site, drilled two holes respectively, and fastened them with suture. We carried on auto-iliac bone grafting with the nonunion bone grafts. The follow-up at 15 months after operation showed that the treatment was successful, X-ray confirmed that there was no rotation and no angular or short deformity. We briefly reviewed the literature regarding such an unusual presentation and discussed in details the possible etiology and the advantages of autologous double-strut fibular grafts to cope with such an intractable situation. Key words: Femur; Transplantation, autologous; Bone screws

  17. Cubesat Proximity Operations Demonstration (CPOD)

    Science.gov (United States)

    Villa, Marco; Martinez, Andres; Petro, Andrew

    2015-01-01

    The CubeSat Proximity Operations Demonstration (CPOD) project will demonstrate rendezvous, proximity operations and docking (RPOD) using two 3-unit (3U) CubeSats. Each CubeSat is a satellite with the dimensions 4 inches x 4 inches x 13 inches (10 centimeters x 10 centimeters x 33 centimeters) and weighing approximately 11 pounds (5 kilograms). This flight demonstration will validate and characterize many new miniature low-power proximity operations technologies applicable to future missions. This mission will advance the state of the art in nanosatellite attitude determination,navigation and control systems, in addition to demonstrating relative navigation capabilities.The two CPOD satellites are scheduled to be launched together to low-Earth orbit no earlier than Dec. 1, 2015.

  18. An Assessment of Femur Growth Parameters in Human Fetuses and Their Relationship to Gestational Age

    OpenAIRE

    ZİYLAN, Taner

    2014-01-01

    Fetal femur length assessment has been the subject of numerous investigations. Skeletal growth disturbances, estimation of fetal gestational age, developmental abnormality and detection of certain fetal congenital anomalies, and determination of population growth characteristics have been the objectives of different investigators' studies. The purpose of this study was to evaluate the relationships between the crown-rump length (CRL) and fetal femur growth parameters and the gestatio...

  19. A histopathological and morphometrical study of femur head cartilage in Wistar rats treated with prednisolone

    OpenAIRE

    Barrueco, J. L.; Gázquez, A; Redondo, E.; Roncero, V; Durán, E.

    1989-01-01

    An analysis was made of histopathological developments in femur head cartilage in a group of Wistar rats receiving a daily intra-muscular injection of 2.5 mg prednisolone. This group was divided into four experimental batches, each consisting of 6 rats. Batches were sacrificed at 15,30,60 and 90 days after the start of the experiment. Degeneration of the femur head cartilage was observed from the start of the experiment (15 days), and gave rise to chondrocy...

  20. Intraoperative Distal Femoral Fine Wire Traction to Facilitate Intramedullary Nailing of the Femur.

    Science.gov (United States)

    Githens, Michael; Alton, Timothy B; Firoozabadi, Reza; Bishop, Julius A

    2016-01-01

    Many techniques have been employed to facilitate intramedullary nailing of femur fractures. Maintaining limb length during the operation can be difficult. The authors describe the use of distal femoral fine wire skeletal traction as a technique to maintain reduction while allowing intramedullary nailing of femur fractures. This technique is safe, is effective, and negates the need for a fracture table or an assistant. Copyright 2016, SLACK Incorporated.

  1. Outcome of fetuses with short femur length detected at second trimester malformation scan - a national survey

    DEFF Research Database (Denmark)

    Mathiesen, Jonathan Michael; Aksglaede, Lise; Skibsted, Lillian

    2014-01-01

    To assess the relationship between fetal femur diaphysis length (FL) below the 5th percentile at the second trimester scan and pregnancy outcome, in a population where more than 90 % of women attend first trimester screening.......To assess the relationship between fetal femur diaphysis length (FL) below the 5th percentile at the second trimester scan and pregnancy outcome, in a population where more than 90 % of women attend first trimester screening....

  2. Constrained ballistics and geometrical optics

    CERN Document Server

    Epstein, Marcelo

    2014-01-01

    The problem of constant-speed ballistics is studied under the umbrella of non-linear non-holonomic constrained systems. The Newtonian approach is shown to be equivalent to the use of Chetaev's rule to incorporate the constraint within the initially unconstrained formulation. Although the resulting equations are not, in principle, obtained from a variational statement, it is shown that the trajectories coincide with those of geometrical optics in a medium with a suitably chosen refractive index, as prescribed by Fermat's principle of least time. This fact gives rise to an intriguing mechano-optical analogy. The trajectories are further studied and discussed.

  3. Geometric Rationalization for Freeform Architecture

    KAUST Repository

    Jiang, Caigui

    2016-06-20

    The emergence of freeform architecture provides interesting geometric challenges with regards to the design and manufacturing of large-scale structures. To design these architectural structures, we have to consider two types of constraints. First, aesthetic constraints are important because the buildings have to be visually impressive. Sec- ond, functional constraints are important for the performance of a building and its e cient construction. This thesis contributes to the area of architectural geometry. Specifically, we are interested in the geometric rationalization of freeform architec- ture with the goal of combining aesthetic and functional constraints and construction requirements. Aesthetic requirements typically come from designers and architects. To obtain visually pleasing structures, they favor smoothness of the building shape, but also smoothness of the visible patterns on the surface. Functional requirements typically come from the engineers involved in the construction process. For exam- ple, covering freeform structures using planar panels is much cheaper than using non-planar ones. Further, constructed buildings have to be stable and should not collapse. In this thesis, we explore the geometric rationalization of freeform archi- tecture using four specific example problems inspired by real life applications. We achieve our results by developing optimization algorithms and a theoretical study of the underlying geometrical structure of the problems. The four example problems are the following: (1) The design of shading and lighting systems which are torsion-free structures with planar beams based on quad meshes. They satisfy the functionality requirements of preventing light from going inside a building as shad- ing systems or reflecting light into a building as lighting systems. (2) The Design of freeform honeycomb structures that are constructed based on hex-dominant meshes with a planar beam mounted along each edge. The beams intersect without

  4. Field guide to geometrical optics

    CERN Document Server

    Greivenkamp, John E

    2004-01-01

    This Field Guide derives from the treatment of geometrical optics that has evolved from both the undergraduate and graduate programs at the Optical Sciences Center at the University of Arizona. The development is both rigorous and complete, and it features a consistent notation and sign convention. This volume covers Gaussian imagery, paraxial optics, first-order optical system design, system examples, illumination, chromatic effects, and an introduction to aberrations. The appendices provide supplemental material on radiometry and photometry, the human eye, and several other topics.

  5. Science, art and geometrical imagination

    Science.gov (United States)

    Luminet, Jean-Pierre

    2011-06-01

    From the geocentric, closed world model of Antiquity to the wraparound universe models of relativistic cosmology, the parallel history of space representations in science and art illustrates the fundamental rôle of geometric imagination in innovative findings. Through the analysis of works of various artists and scientists like Plato, Dürer, Kepler, Escher, Grisey or the author, it is shown how the process of creation in science and in the arts rests on aesthetical principles such as symmetry, regular polyhedra, laws of harmonic proportion, tessellations, group theory, etc., as well as on beauty, conciseness and an emotional approach of the world.

  6. A history of geometrical methods

    CERN Document Server

    Coolidge, Julian Lowell

    2013-01-01

    Full and authoritative, this history of the techniques for dealing with geometric questions begins with synthetic geometry and its origins in Babylonian and Egyptian mathematics; reviews the contributions of China, Japan, India, and Greece; and discusses the non-Euclidean geometries. Subsequent sections cover algebraic geometry, starting with the precursors and advancing to the great awakening with Descartes; and differential geometry, from the early work of Huygens and Newton to projective and absolute differential geometry. The author's emphasis on proofs and notations, his comparisons betwe

  7. The Effect of Weight-Bearing Exercise on the Strength of Femur Bone in Ovariectomized Rats

    Directory of Open Access Journals (Sweden)

    GH Sharifi

    2011-08-01

    Full Text Available Introduction & Objective: Fractures due to osteoporosis after menopause in women is widespread. Osteoporosis may occur in case of inadequate lack of physical activity .The aim of this study was to determine the effect of running training on femur bone strength in ovariectomized rats. Materials & Methods Forty matured Sprague Dawley rats were chosen for this study. A group of 10 were killed randomly to measure their initial femur strength. The remaining rats had ovarian surgery. After three months, in order to reach menopause period, they were randomly divided into 3 groups, including pre test, running training and control groups. The running training program was carried out for one hour a day, five days a week, for eight weeks. Femur bone strength was measured by HOUNSFIELD system. Data was analyzed by using one-way analysis of variance and dependent T- tests by the SPSS software. Results: Results of this study showed that ovariectomy leads to significant decrease of femur bone strength. On the other hand the eight weeks running training lead to significant increase of femur bone strength. Conclusion: The results of this study suggest that life style is important factors in preventing of osteoporosis and running training program had an inhibitory or reversal effect on decrease of menopause-induced femur bone strength.

  8. Long-term radiographic follow-up of bisphosphonate-associated atypical femur fractures

    Energy Technology Data Exchange (ETDEWEB)

    Favinger, Jennifer L. [University of Washington, Department of Radiology, 1959 N.E. Pacific Street, Box 357115, Seattle, WA (United States); Hippe, Daniel [University of Washington, Department of Radiology, Seattle, WA (United States); Ha, Alice S. [University of Washington, Department of Radiology, 4245 Roosevelt Way NE, Box 354755, Seattle, WA (United States)

    2016-05-15

    To evaluate the appearance of bisphosphonate-related femur insufficiency fractures on long-term follow-up radiographic studies and to describe the rate of fracture line obscuration and cortical beak healing over time. In this retrospective study, bisphosphonate-related femur fracture radiographs were reviewed by two radiologists for the presence of a fracture line, callus, and the characteristic cortical beak. Kaplan-Meier curves were used to analyze the time to first indication of healing. Femurs were also subdivided into those who underwent early versus late surgical fixation and those who underwent early versus late discontinuation of bisphosphonate. Clinical data including pain level and medication history were collected. Forty-seven femurs with a bisphosphonate-related femur fracture were identified in 28 women. Eighty-five percent took a bisphosphonate for greater than 5 years and 59 % for greater than 10 years. The median time to beak healing was 265 weeks and the median time to fracture line healing was 56 weeks in the 31 femurs with a baseline fracture. No statistically significant difference was identified between surgical fixation and conservative management. Bisphosphonate-related fractures demonstrate notably prolonged healing time on long-term follow-up. (orig.)

  9. Image understanding using geometric context

    Science.gov (United States)

    Zhang, Xiaochun; Liu, Chuancai

    2017-07-01

    A Gibbs Sampler based topic model for image annotation, which takes into account the interaction between visual geometric context and related topic, is presented. Most of the existing topic models for scene annotation use segmentation-based algorithm. However, topic models using segmentation algorithm alone sometimes can produce erroneous results when used to annotate real-life scene pictures. Therefore, our algorithm makes use of peaks of image surface instead of segmentation regions. Existing approaches use SIFT algorithm and treat the peaks as round blob features. In this paper, the peaks are treated as anisotropic blob features, which models low level visual elements more precisely. In order to better utilize visual features, our model not only takes into consideration visual codeword, but also considers influence of visual properties to topic formation, such as orientation, width, length and color. The basic idea is based on the assumption that different topics will produce distinct visual appearance, and different visual appearance is helpful to distinguish topics. During the learning stage, each topic will be associated with a set of distributions of visual properties, which depicts appearance of the topic. This paper considers more geometric properties, which will reduce topic uncertainty and learn the images better. Tested with Corel5K, SAIAPR-TC12 and Espgame100k Datasets, our method performs moderately better than some state of the arts methods.

  10. Geometric decompositions of collective motion

    Science.gov (United States)

    Mischiati, Matteo; Krishnaprasad, P. S.

    2017-04-01

    Collective motion in nature is a captivating phenomenon. Revealing the underlying mechanisms, which are of biological and theoretical interest, will require empirical data, modelling and analysis techniques. Here, we contribute a geometric viewpoint, yielding a novel method of analysing movement. Snapshots of collective motion are portrayed as tangent vectors on configuration space, with length determined by the total kinetic energy. Using the geometry of fibre bundles and connections, this portrait is split into orthogonal components each tangential to a lower dimensional manifold derived from configuration space. The resulting decomposition, when interleaved with classical shape space construction, is categorized into a family of kinematic modes-including rigid translations, rigid rotations, inertia tensor transformations, expansions and compressions. Snapshots of empirical data from natural collectives can be allocated to these modes and weighted by fractions of total kinetic energy. Such quantitative measures can provide insight into the variation of the driving goals of a collective, as illustrated by applying these methods to a publicly available dataset of pigeon flocking. The geometric framework may also be profitably employed in the control of artificial systems of interacting agents such as robots.

  11. SHORT COMMUNICATION PROXIMATE COMPOSITION, MINERAL ...

    African Journals Online (AJOL)

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    SHORT COMMUNICATION. PROXIMATE COMPOSITION, MINERAL CONTENT AND ANTINUTRITIONAL. FACTORS OF SOME CAPSICUM (Capsicum annum) VARIETIES GROWN IN. ETHIOPIA. Esayas K.1, Shimelis A.2, Ashebir F.3, Negussie R.3, Tilahun B.4 and Gulelat D.4*. 1Hawassa University, Department of Food ...

  12. Arterial Injury to the Profunda Femoris Artery following Internal Fixation of a Neck of Femur Fracture with a Compression Hip Screw

    Directory of Open Access Journals (Sweden)

    Simon Craxford

    2013-01-01

    Full Text Available We report the case of an 82-year-old woman who developed extensive proximal thigh swelling and persistent anaemia following internal fixation of an extracapsular neck of femur fracture with a dynamic hip screw (DHS. This was revealed to be a pseudoaneurysm of a branch of profunda femoris artery on angiography. Her case was further complicated by a concurrent pulmonary embolism (PE. She underwent endovascular coil embolisation of the pseudoaneurysm. An IVC filter was inserted and the patient was fully anticoagulated once it had been ensured that there was no active bleeding. In this case, we review the potential for anatomical variations in the blood supply to this region and discuss treatment options for a complicated patient. We recommend that a pseudoaneurysm should be part of a differential diagnosis for postoperative patients with anaemia refractory to blood transfusion so as not to miss this rare but potentially serious complication.

  13. Reducing returns to theatre for neck of femur fracture patients.

    Science.gov (United States)

    Graham, Selina; Dahill, Mark; Robinson, Derek

    2017-01-01

    The Royal United Hospital, Bath, admits approximately 550 patients with neck of femur fractures per year. The risks from returning to theatre for this patient group are often life-threatening. Post-operative wound ooze was noted to cause a significant rate of return to theatre, with increased lengths of stay and patient morbidity. A wound closure protocol was agreed by the consultant body. This information was disseminated by email and teaching sessions to all members of the multidisciplinary team, including surgeons, theatre staff and ortho-geriatricians. The plan-do-study-act model for improvement was used to reduce rates of returns to theatre for wound ooze. Interventions included cyclical teaching during each trainee rotation, updated inductions, posters, email reminders and scrub team involvement to open the protocol sutures unprompted. The primary outcome measure was returns to theatre for wound complications. Baseline data showed 4 returns to theatre over a two month period (4.40% of patients). Length of stay for each patient affected by wound ooze was also compared to the departmental mean. In the 6 month intervention period there was one return to theatre (0.36% of patients). The observed reduction saved the department an estimated £13,831 in length of stay alone. The standardisation of wound closure protocol, with continued reinforcement to all members of the multidisciplinary team, improves patient outcome in this group. Mobilising a group of clinicians across a variety of specialities, with one common goal, is highly effective for patients, improves multidisciplinary working and reduces cost.

  14. Systemic treatment with telmisartan improves femur fracture healing in mice.

    Science.gov (United States)

    Zhao, Xiong; Wang, Jia-xing; Feng, Ya-fei; Wu, Zi-xiang; Zhang, Yang; Shi, Lei; Tan, Quan-chang; Yan, Ya-bo; Lei, Wei

    2014-01-01

    Recent clinical studies indicated that angiotensin receptor blockers (ARBs) would decrease the risk of bone fractures in the elderly populations. There is little known about the role of the ARBs in the process of fracture healing. The purpose of the present study was to verify the hypothesis that systemic treatment with telmisartan has the ability to promote fracture healing. In this study, femur fractures were produced in 96 mature male BALB/c mice. Animals were treated with the ARBs telmisartan or vehicle. Fracture healing was analysed after 2, 5 and 10 weeks postoperatively using X-ray, biomechanical testing, histomorphometry, immunohistochemistry and micro-computed tomography (micro-CT). Radiological analysis showed the diameter of the callus in the telmisartan treated animals was significantly increased when compared with that of vehicle treated controls after two weeks of fracture healing. The radiologically observed promotion of callus formation was confirmed by histomorphometric analyses, which revealed a significantly increased amount of bone formation when compared with vehicle-treated controls. Biomechanical testing further showed a significantly greater peak torque at failure, and a higher torsional stiffness in telmisartan-treated animals compared with controls. There was an increased fraction of PCNA-positive cells and VEGF-positive cells in telmisartan-treated group compared with vehicle-treated controls. From the three-dimensional reconstruction of the bony callus, telmisartan-treated group significantly increased the values of BV/TV by 21.7% and CsAr by 26.0% compared to the vehicle-treated controls at 5 weeks post-fracture. In summary, we demonstrate in the current study that telmisartan could promote fracture healing in a mice model via increasing mechanical strength and improving microstructure. The most mechanism is probably by an increase of cell proliferation and neovascularization associated with a decreased VEGF expression in hypertrophic

  15. Systemic Treatment with Telmisartan Improves Femur Fracture Healing in Mice

    Science.gov (United States)

    Wu, Zi-xiang; Zhang, Yang; Shi, Lei; Tan, Quan-chang; Yan, Ya-bo; Lei, Wei

    2014-01-01

    Recent clinical studies indicated that angiotensin receptor blockers (ARBs) would decrease the risk of bone fractures in the elderly populations. There is little known about the role of the ARBs in the process of fracture healing. The purpose of the present study was to verify the hypothesis that systemic treatment with telmisartan has the ability to promote fracture healing. In this study, femur fractures were produced in 96 mature male BALB/c mice. Animals were treated with the ARBs telmisartan or vehicle. Fracture healing was analysed after 2, 5 and 10 weeks postoperatively using X-ray, biomechanical testing, histomorphometry, immunohistochemistry and micro-computed tomography (micro-CT). Radiological analysis showed the diameter of the callus in the telmisartan treated animals was significantly increased when compared with that of vehicle treated controls after two weeks of fracture healing. The radiologically observed promotion of callus formation was confirmed by histomorphometric analyses, which revealed a significantly increased amount of bone formation when compared with vehicle-treated controls. Biomechanical testing further showed a significantly greater peak torque at failure, and a higher torsional stiffness in telmisartan-treated animals compared with controls. There was an increased fraction of PCNA-positive cells and VEGF-positive cells in telmisartan-treated group compared with vehicle-treated controls. From the three-dimensional reconstruction of the bony callus, telmisartan-treated group significantly increased the values of BV/TV by 21.7% and CsAr by 26.0% compared to the vehicle-treated controls at 5 weeks post-fracture. In summary, we demonstrate in the current study that telmisartan could promote fracture healing in a mice model via increasing mechanical strength and improving microstructure. The most mechanism is probably by an increase of cell proliferation and neovascularization associated with a decreased VEGF expression in hypertrophic

  16. Pertrochanteric osteotomy and distraction femoral neck lengthening for treatment of proximal hip ischemic deformities in children.

    Science.gov (United States)

    Teplenky, Mikhail; Mekki, Waleed

    2016-02-01

    Proximal femoral ischemic deformities in the pediatric population is a challenging pathological situation. Many surgical techniques have been proposed to treat this problem, with variable reported results. We believe that a C-shaped pertrochanteric osteotomy plus neck lengthening utilizing distraction osteogenesis principles would restore the femoral anatomical ratios between neck, shaft, and the head, and redress the biomechanics of the proximal femur with resultant sufficient containment of the femoral head within the acetabulum. We reviewed the results of 19 patients divided into two groups with proximal femoral ischemic deformities. Between 2002 and 2009, preoperative and postoperative clinical examination and radiographs were assessed measuring the neck-shaft angle (NSA), neck-epiphyseal angle (NEA), articulo-trochanteric distance (ATD), lateralization of the greater trochanter (LT), the angle of Wiberg (CEA), index of lateral head displacement by Reimers (IM), and lateral angle of displacement (LDA). All patients were followed prospectively. Clinical outcome was assessed using Colton's criteria, which showed average good improvement in function (58.9 %). Radiological indicators were assessed using Kruczynski's criteria. For group I, the postoperative NSA, NEA, and CEA showed significant change (p < 0.01, p < 0.001, and p < 0.001, respectively). For group II, the postoperative NSA, NEA, and CEA showed significant change (p < 0.001, p < 0.001, and p < 0.001, respectively). The midterm functional results are favorable for the implementation of pertrochanteric osteotomy and distraction osteogenesis to treat proximal femoral ischemic deformities in the pediatric population.

  17. Hip abductor moment arm - a mathematical analysis for proximal femoral replacement

    Directory of Open Access Journals (Sweden)

    Temple H Thomas

    2011-01-01

    Full Text Available Abstract Background Patients undergoing proximal femoral replacement for tumor resection often have compromised hip abductor muscles resulting in a Trendelenberg limp and hip instability. Commercially available proximal femoral prostheses offer several designs with varying sites of attachment for the abductor muscles, however, no analyses of these configurations have been performed to determine which design provides the longest moment arm for the hip abductor muscles during normal function. Methods This study analyzed hip abductor moment arm through hip adduction and abduction with a trigonometric mathematical model to evaluate the effects of alterations in anatomy and proximal femoral prosthesis design. Prosthesis dimensions were taken from technical schematics that were obtained from the prosthesis manufacturers. Manufacturers who contributed schematics for this investigation were Stryker Orthopaedics and Biomet. Results Superior and lateral displacement of the greater trochanter increased the hip abductor mechanical advantage for single-leg stance and adduction and preserved moment arm in the setting of Trendelenberg gait. Hip joint medialization resulted in less variance of the abductor moment arm through coronal motion. The Stryker GMRS endoprosthesis provided the longest moment arm in single-leg stance. Conclusions Hip abductor moment arm varies substantially throughout the hip's range of motion in the coronal plane. Selection of a proximal femur endoprosthesis with an abductor muscle insertion that is located superiorly and laterally will optimize hip abductor moment arm in single-leg stance compared to one located inferiorly or medially.

  18. Effects of ligation of lateral intermuscular septum perforating vessels on blood supply to the femur.

    Science.gov (United States)

    Grob, K; Manestar, M; Lang, A; Ackland, T; Gilbey, H; Kuster, M S

    2015-12-01

    With a subvastus approach to the femur, the vessels that perforate the lateral intermuscular septum (LISP-vessels) must be ligated. The effect on the blood supply to the femur remains unclear. The purpose of the current study was to investigate the effect of ligation of the LISP-Vessels on the blood supply and to examine the anatomy of the LISP-vessels and the anastomoses around the femur. In six human cadavers the LISP vessels were ligated by a lateral subvastus approach on one side. The contralateral side served as control group. After bilateral injection of different coloured silicon dyes into the lateral and medial circumflex femoral artery (green), deep femoral artery (red) and the superficial femoral artery (blue) dissection was performed bilaterally. The arterial perfusion on both sides was compared and the anatomy of the LISP vessels studied. The medullary perfusion of the femur was not altered by the ligation of the LISP vessels. It did also not lead to a decrease in periosteal vessel filling. The LISP vessels were shown to be a part of a complex and rich anastomotic network and play an important role in the perfusion of the femur and quadriceps muscle group. The ligature could be compensated for by this anastomotic network. Branches to the periosteum separate from the LISP vessels immediately after perforating the lateral intermuscular septum. The linea aspera turned out to be an important area for the femoral blood supply. Exposure of the femur through a lateral subvastus approach with ligation of LISP vessels causes a certain degree of soft tissue trauma. However, by using a gentle surgical technique the periostal perfusion of the femur can be preserved by a potent anastomotic network after ligation of the LISP vessels if they are not ligated to close to the lateral intermuscular septum and the linea aspera is not unnecessarily exposed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Geometrical charged-particle optics

    CERN Document Server

    Rose, Harald

    2012-01-01

    This second edition is an extended version of the first edition of Geometrical Charged-Particle Optics. The updated reference monograph is intended as a guide for researchers and graduate students who are seeking a comprehensive treatment of the design of instruments and beam-guiding systems of charged particles and their propagation in electromagnetic fields. Wave aspects are included in this edition for explaining electron holography, the Aharanov-Bohm effect and the resolution of electron microscopes limited by diffraction. Several methods for calculating the electromagnetic field are presented and procedures are outlined for calculating the properties of systems with arbitrarily curved axis. Detailed methods are presented for designing and optimizing special components such as aberration correctors, spectrometers, energy filters monochromators, ion traps, electron mirrors and cathode lenses. In particular, the optics of rotationally symmetric lenses, quadrupoles, and systems composed of these elements are...

  20. Geometric Methods in Physics XXXV

    CERN Document Server

    Odzijewicz, Anatol; Previato, Emma

    2018-01-01

    This book features a selection of articles based on the XXXV Białowieża Workshop on Geometric Methods in Physics, 2016. The series of Białowieża workshops, attended by a community of experts at the crossroads of mathematics and physics, is a major annual event in the field. The works in this book, based on presentations given at the workshop, are previously unpublished, at the cutting edge of current research, typically grounded in geometry and analysis, and with applications to classical and quantum physics. In 2016 the special session "Integrability and Geometry" in particular attracted pioneers and leading specialists in the field. Traditionally, the Białowieża Workshop is followed by a School on Geometry and Physics, for advanced graduate students and early-career researchers, and the book also includes extended abstracts of the lecture series.

  1. Adaptive Bone Remodeling of the Femoral Bone After Tumor Resection Arthroplasty With an Uncemented Proximally Hydroxyapatite-Coated Stem

    DEFF Research Database (Denmark)

    Andersen, Mikkel R.; Petersen, Michael M.

    2016-01-01

    -fluted 125-mm uncemented press-fit titanium alloy stem with hydroxyapatite coating of the proximal part of the stem. Measurements of bone mineral density (BMD; g/cm2) were done postoperatively and after 3, 6, and 12 mo in the part of the femur bone containing the Global Modular Replacement System stem using...... of 8%-9% during the first postoperative year was seen along the femoral stem, but in the bone containing the hydroxyapatite-coated part of the stem, the decrease in BMD was 14%, thus indicating that stress shielding of this part of the bone may play a role for the adaptive bone remodeling....

  2. Geometrical factors in the perception of sacredness

    DEFF Research Database (Denmark)

    Costa, Marco; Bonetti, Leonardo

    2016-01-01

    Geometrical and environmental factors in the perception of sacredness, dominance, and attractiveness were assessed by 137 participants in five tests. In the first test, a two-alternative forced-choice paradigm was used to test the perception of sacredness, dominance, and attractiveness in geometr......Geometrical and environmental factors in the perception of sacredness, dominance, and attractiveness were assessed by 137 participants in five tests. In the first test, a two-alternative forced-choice paradigm was used to test the perception of sacredness, dominance, and attractiveness...... in geometrical figures differing in shape, verticality, size, and symmetry. Verticality, symmetry, and convexity were found to be important factors in the perception of sacredness. In the second test, participants had to mark the point inside geometrical surfaces that was perceived as most sacred, dominant....... Geometrical factors in the perception of sacredness, dominance, and attractiveness were largely overlapping....

  3. Guide to Geometric Algebra in Practice

    CERN Document Server

    Dorst, Leo

    2011-01-01

    This highly practical "Guide to Geometric Algebra in Practice" reviews algebraic techniques for geometrical problems in computer science and engineering, and the relationships between them. The topics covered range from powerful new theoretical developments, to successful applications, and the development of new software and hardware tools. This title: provides hands-on review exercises throughout the book, together with helpful chapter summaries; presents a concise introductory tutorial to conformal geometric algebra (CGA) in the appendices; examines the application of CGA for the d

  4. Geometric Analogue of Holographic Reduced Representation

    OpenAIRE

    Aerts, Diederik; Czachor, Marek; De Moor, Bart

    2007-01-01

    Holographic reduced representations (HRR) are based on superpositions of convolution-bound $n$-tuples, but the $n$-tuples cannot be regarded as vectors since the formalism is basis dependent. This is why HRR cannot be associated with geometric structures. Replacing convolutions by geometric products one arrives at reduced representations analogous to HRR but interpretable in terms of geometry. Variable bindings occurring in both HRR and its geometric analogue mathematically correspond to two ...

  5. Geometric magnetism in open quantum systems

    OpenAIRE

    Campisi, Michele; Denisov, Sergey; Hänggi, Peter

    2012-01-01

    An isolated classical chaotic system, when driven by the slow change of several parameters, responds with two reaction forces: geometric friction and geometric magnetism. By using the theory of quantum fluctuation relations we show that this holds true also for open quantum systems, and provide explicit expressions for those forces in this case. This extends the concept of Berry curvature to the realm of open quantum systems. We illustrate our findings by calculating the geometric magnetism o...

  6. Photoactivated In Vivo Proximity Labeling.

    Science.gov (United States)

    Beck, David B; Bonasio, Roberto

    2017-06-19

    Identification of molecular interactions is paramount to understanding how cells function. Most available technologies rely on co-purification of a protein of interest and its binding partners. Therefore, they are limited in their ability to detect low-affinity interactions and cannot be applied to proteins that localize to difficult-to-solubilize cellular compartments. In vivo proximity labeling (IPL) overcomes these obstacles by covalently tagging proteins and RNAs based on their proximity in vivo to a protein of interest. In IPL, a heterobifunctional probe comprising a photoactivatable moiety and biotin is recruited by a monomeric streptavidin tag fused to a protein of interest. Following UV irradiation, candidate interacting proteins and RNAs are covalently biotinylated with tight spatial and temporal control and subsequently recovered using biotin as an affinity handle. Here, we describe experimental protocols to discover novel protein-protein and protein-RNA interactions using IPL. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  7. Geometrical and Graphical Solutions of Quadratic Equations.

    Science.gov (United States)

    Hornsby, E. John, Jr.

    1990-01-01

    Presented are several geometrical and graphical methods of solving quadratic equations. Discussed are Greek origins, Carlyle's method, von Staudt's method, fixed graph methods and imaginary solutions. (CW)

  8. Geometric Aspects of Iterated Matrix Multiplication

    DEFF Research Database (Denmark)

    Gesmundo, Fulvio

    2016-01-01

    This paper studies geometric properties of the Iterated Matrix Multiplication polynomial and the hypersurface that it defines. We focus on geometric aspects that may be relevant for complexity theory such as the symmetry group of the polynomial, the dual variety and the Jacobian loci of the hyper......This paper studies geometric properties of the Iterated Matrix Multiplication polynomial and the hypersurface that it defines. We focus on geometric aspects that may be relevant for complexity theory such as the symmetry group of the polynomial, the dual variety and the Jacobian loci...

  9. Prox-1 Automated Proximity Operations

    Science.gov (United States)

    2016-01-13

    on demonstrating the functionality required to meet minimum mission success criteria. The minimum mission includes on- orbit spacecraft checkout of...also includes deployment of LightSail-B from the P-POD, and imaging of LightSail-B for 20 minutes as it recedes from Prox-1. small satellite ; proximity...criteria. The minimum mission includes on- orbit spacecraft checkout of all spacecraft subsystems, including flight qualification of the following new

  10. Poly-N-acetyl glucosamine fibers activate bone regeneration in a rabbit femur injury model.

    Science.gov (United States)

    Muise-Helmericks, Robin C; Demcheva, Marina; Vournakis, John N; Seth, Arun

    2011-08-01

    The purpose of this study was to evaluate the ability of a membrane material, consisting only of short poly-N-acetyl glucosamine (sNAG) nanofibers, to regenerate bone tissue after implantation into circular holes in the rabbit femur. Three circular holes were created in the femurs of five male New Zealand white rabbits. The holes were ∼ 2.0 mm in diameter. Three holes in the left femur were implanted with the comparative control substance (Bone Wax; Ethicon, Inc.); three holes in the right femur were implanted with the sNAG membrane test article. Animals were killed 4 weeks after surgery, and macroscopic evaluation of the implant sites was made. Hematoxylin and eosin histology was performed on both control and test sites. All control (bone wax) sites had visible holes (defects) at the 28-day end point of the study and showed no evidence of new bone formation. All the 15 sNAG test sites were found to have new bone tissue present in the bone hole defects. Hematoxylin and eosin histology of the sNAG-treated test sites showed the presence of osteoblasts, osteocytes, and trabecula of new bone formation at the 28-day end point of the study. The sNAG membrane test material activated the regeneration of new bone tissue in a rabbit femur bone model after 28 days of implantation, whereas the control bone wax material did not.

  11. Establishing the 3-D finite element solid model of femurs in partial by volume rendering.

    Science.gov (United States)

    Zhang, Yinwang; Zhong, Wuxue; Zhu, Haibo; Chen, Yun; Xu, Lingjun; Zhu, Jianmin

    2013-01-01

    It remains rare to report three-dimensional (3-D) finite element solid model of femurs in partial by volume rendering method, though several methods of femoral 3-D finite element modeling are already available. We aim to analyze the advantages of the modeling method by establishing the 3-D finite element solid model of femurs in partial by volume rendering. A 3-D finite element model of the normal human femurs, made up of three anatomic structures: cortical bone, cancellous bone and pulp cavity, was constructed followed by pretreatment of the CT original image. Moreover, the finite-element analysis was carried on different material properties, three types of materials given for cortical bone, six assigned for cancellous bone, and single for pulp cavity. The established 3-D finite element of femurs contains three anatomical structures: cortical bone, cancellous bone, and pulp cavity. The compressive stress primarily concentrated in the medial surfaces of femur, especially in the calcar femorale. Compared with whole modeling by volume rendering method, the 3-D finite element solid model created in partial is more real and fit for finite element analysis. Copyright © 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  12. Discrete geometric structures for architecture

    KAUST Repository

    Pottmann, Helmut

    2010-06-13

    The emergence of freeform structures in contemporary architecture raises numerous challenging research problems, most of which are related to the actual fabrication and are a rich source of research topics in geometry and geometric computing. The talk will provide an overview of recent progress in this field, with a particular focus on discrete geometric structures. Most of these result from practical requirements on segmenting a freeform shape into planar panels and on the physical realization of supporting beams and nodes. A study of quadrilateral meshes with planar faces reveals beautiful relations to discrete differential geometry. In particular, we discuss meshes which discretize the network of principal curvature lines. Conical meshes are among these meshes; they possess conical offset meshes at a constant face/face distance, which in turn leads to a supporting beam layout with so-called torsion free nodes. This work can be generalized to a variety of multilayer structures and laid the ground for an adapted curvature theory for these meshes. There are also efforts on segmenting surfaces into planar hexagonal panels. Though these are less constrained than planar quadrilateral panels, this problem is still waiting for an elegant solution. Inspired by freeform designs in architecture which involve circles and spheres, we present a new kind of triangle mesh whose faces\\' in-circles form a packing, i.e., the in-circles of two triangles with a common edge have the same contact point on that edge. These "circle packing (CP) meshes" exhibit an aesthetic balance of shape and size of their faces. They are closely tied to sphere packings on surfaces and to various remarkable structures and patterns which are of interest in art, architecture, and design. CP meshes constitute a new link between architectural freeform design and computational conformal geometry. Recently, certain timber structures motivated us to study discrete patterns of geodesics on surfaces. This

  13. Generalized Geometric Quantum Speed Limits

    Directory of Open Access Journals (Sweden)

    Diego Paiva Pires

    2016-06-01

    Full Text Available The attempt to gain a theoretical understanding of the concept of time in quantum mechanics has triggered significant progress towards the search for faster and more efficient quantum technologies. One of such advances consists in the interpretation of the time-energy uncertainty relations as lower bounds for the minimal evolution time between two distinguishable states of a quantum system, also known as quantum speed limits. We investigate how the nonuniqueness of a bona fide measure of distinguishability defined on the quantum-state space affects the quantum speed limits and can be exploited in order to derive improved bounds. Specifically, we establish an infinite family of quantum speed limits valid for unitary and nonunitary evolutions, based on an elegant information geometric formalism. Our work unifies and generalizes existing results on quantum speed limits and provides instances of novel bounds that are tighter than any established one based on the conventional quantum Fisher information. We illustrate our findings with relevant examples, demonstrating the importance of choosing different information metrics for open system dynamics, as well as clarifying the roles of classical populations versus quantum coherences, in the determination and saturation of the speed limits. Our results can find applications in the optimization and control of quantum technologies such as quantum computation and metrology, and might provide new insights in fundamental investigations of quantum thermodynamics.

  14. Simulating geometrically complex blast scenarios

    Directory of Open Access Journals (Sweden)

    Ian G. Cullis

    2016-04-01

    Full Text Available The effects of blast waves generated by energetic and non-energetic sources are of continuing interest to the ballistics research community. Modern conflicts are increasingly characterised by asymmetric urban warfare, with improvised explosive devices (IEDs often playing a dominant role on the one hand and an armed forces requirement for minimal collateral effects from their weapons on the other. These problems are characterised by disparate length- and time-scales and may also be governed by complex physics. There is thus an increasing need to be able to rapidly assess and accurately predict the effects of energetic blast in topologically complex scenarios. To this end, this paper presents a new QinetiQ-developed advanced computational package called EAGLE-Blast, which is capable of accurately resolving the generation, propagation and interaction of blast waves around geometrically complex shapes such as vehicles and buildings. After a brief description of the numerical methodology, various blast scenario simulations are described and the results compared with experimental data to demonstrate the validation of the scheme and its ability to describe these complex scenarios accurately and efficiently. The paper concludes with a brief discussion on the use of the code in supporting the development of algorithms for fast running engineering models.

  15. Geometric Computations On Indecisive Points

    DEFF Research Database (Denmark)

    Jørgensen, Allan Grønlund; Phillips, Jeff; Loffler, Maarten

    2011-01-01

    We study computing with indecisive point sets. Such points have spatial uncertainty where the true location is one of a finite number of possible locations. This data arises from probing distributions a few times or when the location is one of a few locations from a known database. In particular,......-hard. We generalize our polynomial-time algorithm to all LP-type problems. We also utilize our indecisive framework to deterministically and approximately compute on a more general class of uncertain data where the location of each point is given by a probability distribution.......We study computing with indecisive point sets. Such points have spatial uncertainty where the true location is one of a finite number of possible locations. This data arises from probing distributions a few times or when the location is one of a few locations from a known database. In particular......, we study computing distributions of geometric functions such as the radius of the smallest enclosing ball and the diameter. Surprisingly, we can compute the distribution of the radius of the smallest enclosing ball exactly in polynomial time, but computing the same distribution for the diameter is #P...

  16. Geometric reasoning about assembly tools

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, R.H.

    1997-01-01

    Planning for assembly requires reasoning about various tools used by humans, robots, or other automation to manipulate, attach, and test parts and subassemblies. This paper presents a general framework to represent and reason about geometric accessibility issues for a wide variety of such assembly tools. Central to the framework is a use volume encoding a minimum space that must be free in an assembly state to apply a given tool, and placement constraints on where that volume must be placed relative to the parts on which the tool acts. Determining whether a tool can be applied in a given assembly state is then reduced to an instance of the FINDPLACE problem. In addition, the author presents more efficient methods to integrate the framework into assembly planning. For tools that are applied either before or after their target parts are mated, one method pre-processes a single tool application for all possible states of assembly of a product in polynomial time, reducing all later state-tool queries to evaluations of a simple expression. For tools applied after their target parts are mated, a complementary method guarantees polynomial-time assembly planning. The author presents a wide variety of tools that can be described adequately using the approach, and surveys tool catalogs to determine coverage of standard tools. Finally, the author describes an implementation of the approach in an assembly planning system and experiments with a library of over one hundred manual and robotic tools and several complex assemblies.

  17. Engineering Design by Geometric Programming

    Directory of Open Access Journals (Sweden)

    Chia-Hui Huang

    2013-01-01

    Full Text Available A geometric program (GP is a type of mathematical optimization problem characterized by objective and constraint functions, where all functions are of signomial form. The importance of GP comes from two relatively recent developments: (i new methods can solve even large-scale GP extremely efficiently and reliably; (ii a number of practical problems have recently been found to be equivalent to or approximated by GP. This study proposes an optimization approach for solving GP. Our approach is first to convert all signomial terms in GP into convex and concave terms. Then the concave terms are further treated with the proposed piecewise linearization method where only binary variables are used. It has the following features: (i it offers more convenient and efficient means of expressing a piecewise linear function; (ii fewer 0-1 variables are used; (iii the computational results show that the proposed method is much more efficient and faster than the conventional one, especially when the number of break points becomes large. In addition, the engineering design problems are illustrated to evaluate the usefulness of the proposed methods.

  18. Geometric Phase Generated Optical Illusion.

    Science.gov (United States)

    Yue, Fuyong; Zang, Xiaofei; Wen, Dandan; Li, Zile; Zhang, Chunmei; Liu, Huigang; Gerardot, Brian D; Wang, Wei; Zheng, Guoxing; Chen, Xianzhong

    2017-09-12

    An optical illusion, such as "Rubin's vase", is caused by the information gathered by the eye, which is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source. Metasurfaces are metamaterials of reduced dimensionality which have opened up new avenues for flat optics. The recent advancement in spin-controlled metasurface holograms has attracted considerate attention, providing a new method to realize optical illusions. We propose and experimentally demonstrate a metasurface device to generate an optical illusion. The metasurface device is designed to display two asymmetrically distributed off-axis images of "Rubin faces" with high fidelity, high efficiency and broadband operation that are interchangeable by controlling the helicity of the incident light. Upon the illumination of a linearly polarized light beam, the optical illusion of a 'vase' is perceived. Our result provides an intuitive demonstration of the figure-ground distinction that our brains make during the visual perception. The alliance between geometric metasurface and the optical illusion opens a pathway for new applications related to encryption, optical patterning, and information processing.

  19. Use of oral anticoagulants after intramedullary nailing of femur and tibial fractures in trauma department

    Directory of Open Access Journals (Sweden)

    A. K. Dulaev

    2014-01-01

    Full Text Available The authors evaluated of the effectiveness of new oral anticoagulants in patients with diaphyseal fractures of the femur and tibia.We analyzed the effectiveness of thromboprophylaxis in 85 patients with diaphyseal fractures of the femur and tibia in the early postoperative period. Patients were divided into 3 groups: group 1 - patients, who was taking enoxaparin, group 2 - dabigatran etexilate, group 3 - rivaroxaban. We evaluated the frequency of thromboembolic complications and bleeding for 4 weeks after intramedullary nailing of femur and tibia.The lowest frequency of postoperative bleeding was observed in patients treated with dabigatran etexilate. In addition, the minimum frequency of complications was observed among patients of the second group of the study (9.7% in the group receiving dabigatran etexilati compared with 27.8% for the combined group I and III.Statistically significant differences between groups of patients taking oral or parenteral anticoagulants was not obtained.

  20. PROXIMATE AND ELEMENTAL COMPOSITION OF WHITE GRUBS

    African Journals Online (AJOL)

    DR. AMINU

    PROXIMATE AND ELEMENTAL COMPOSITION OF WHITE GRUBS. 1 Alhassan, A. J. 1M .S. Sule, 1J. ... ABSTRACT. This study determined the proximate and mineral element composition of whole white grubs using standard methods of analysis. Proximate ... days, before pulverized to powder and kept in plastic container.

  1. Geometric optical optimization of the corneal lens of Notonecta glauca.

    Science.gov (United States)

    Horváth, G

    1989-08-09

    The optimal shape of the corneal lens of the water bug backswimmer (Notonecta glauca) and the optimal shape and position of the thin transition layer between the distal and proximal units of its cornea are theoretically determined. Using a geometric optical method, first the shape of a geometric interface between the lens units is determined, which eliminates the longitudinal spherical aberration. This interface is investigated for differently formed thick lenses when the medium in contact with the entrance surface of the lens is water or air. The optimal transition layer for the amphibious backswimmer is that, the boundaries of which are the theoretical interfaces for water and air, and the refractive index varies continuously in it. The optimal shape of the corneal lens is determined, with the disadvantageous lenses, with respect to the possible minimal spherical aberration and amount of reflected light from the transition layer, being rejected. The optimal position of the transition layer in the cornea can be obtained from the minimization of the amount of diffracted light on the marginal connection of the layers. The optimal corneal lens for backswimmer has ellipsoid boundary surfaces; the optimal transition layer in it is thin bell-shaped, at the marginal connection of which there is no dimple, the maximum of the layer is on the margin of the cornea. The shape of the theoretically optimal corneal lens, the shape and position of the theoretically optimal transition layer agree well with those of Notonecta glauca. The question posed, the geometric optical method used and the results presented are of general importance, and not only with respect to vision in the bug Notonecta, but also in the fossil trilobites, or in the wave guide theories which have been employed in similar modelling problems, in design of system of lenses without spherical aberration, for example.

  2. Preoperative assessment of the cancellous bone mineral density of the proximal humerus using CT data

    Energy Technology Data Exchange (ETDEWEB)

    Krappinger, Dietmar; Roth, Tobias; Gschwentner, Martin; Suckert, Armin; Blauth, Michael; Hengg, Clemens; Kralinger, Franz [Innsbruck Medical University, Department of Trauma Surgery and Sports Medicine, Innsbruck (Austria)

    2012-03-15

    Osteoporotic fractures of the proximal humerus show an increasing incidence. Osteoporosis not only influences the fracture risk after low-energy trauma, but also affects the mechanical stability of internal fixation. Preoperative assessment of the local bone quality may be useful in the surgical treatment of patients sustaining these injuries. The aim of the present study was to present a method for the preoperative assessment of the local cancellous bone mineral density (BMD) of the proximal humerus using CT data. In the first part of the study, CT scans of 30 patients with unilateral fractures of the proximal humerus after low-energy trauma were used. The local BMD was assessed on the contralateral uninjured side. All 30 patients additionally underwent dual-emission X-ray absorptiometry (DXA) of the lumbar spine, proximal femur, and forearm of the side of the uninjured proximal humerus within 6 weeks after trauma. Three independent trauma surgeons performed measurements on the uninjured proximal humerus twice with a time interval of 4 weeks in order to assess the inter- and intraobserver reliability of the method. In the second part of the study, the local BMD of 507 patients with either proximal humerus fractures or chronic shoulder instability was assessed by a single trauma surgeon. In both parts, the average HU values in standardized ROIs of the humeral head were automatically calculated after correcting for HU values below the water equivalent. A linear calibration equation was computed for the calculation from HU to BMD using a calibration device (EFP). The intra- and interobserver reliability was high (ICC > 0.95). Correlation coefficients between the local BMD of the proximal humerus and other anatomical sites were between 0.35 (lumbar spine) and 0.64 (forearm). We found a high correlation between the local BMD and age. The BMD in the fracture group was significantly lower than in the instability group. These patients were significantly older and more

  3. Geometric integrators for stochastic rigid body dynamics

    KAUST Repository

    Tretyakov, Mikhail

    2016-01-05

    Geometric integrators play an important role in simulating dynamical systems on long time intervals with high accuracy. We will illustrate geometric integration ideas within the stochastic context, mostly on examples of stochastic thermostats for rigid body dynamics. The talk will be mainly based on joint recent work with Rusland Davidchak and Tom Ouldridge.

  4. Parabolas: Connection between Algebraic and Geometrical Representations

    Science.gov (United States)

    Shriki, Atara

    2011-01-01

    A parabola is an interesting curve. What makes it interesting at the secondary school level is the fact that this curve is presented in both its contexts: algebraic and geometric. Being one of Apollonius' conic sections, the parabola is basically a geometric entity. It is, however, typically known for its algebraic characteristics, in particular…

  5. GEOMETRIC IDENTITIES IN STEREOLOGICAL PARTICLE ANALYSIS

    Directory of Open Access Journals (Sweden)

    Stephan Kötzer

    2011-05-01

    Full Text Available The paper reviews recent findings about geometric identities in integral geometry and geometric tomography, and their statistical application to stereological particle analysis. Open questions are discussed. This survey can also serve as an introduction to modern stereological particle analysis for readers who are interested in the mathematical background of the new methods.

  6. Geometric phases in discrete dynamical systems

    Energy Technology Data Exchange (ETDEWEB)

    Cartwright, Julyan H.E., E-mail: julyan.cartwright@csic.es [Instituto Andaluz de Ciencias de la Tierra, CSIC–Universidad de Granada, E-18100 Armilla, Granada (Spain); Instituto Carlos I de Física Teórica y Computacional, Universidad de Granada, E-18071 Granada (Spain); Piro, Nicolas, E-mail: nicolas.piro@epfl.ch [École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne (Switzerland); Piro, Oreste, E-mail: piro@imedea.uib-csic.es [Departamento de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Tuval, Idan, E-mail: ituval@imedea.uib-csic.es [Mediterranean Institute for Advanced Studies, CSIC–Universitat de les Illes Balears, E-07190 Mallorca (Spain)

    2016-10-14

    In order to study the behaviour of discrete dynamical systems under adiabatic cyclic variations of their parameters, we consider discrete versions of adiabatically-rotated rotators. Parallelling the studies in continuous systems, we generalize the concept of geometric phase to discrete dynamics and investigate its presence in these rotators. For the rotated sine circle map, we demonstrate an analytical relationship between the geometric phase and the rotation number of the system. For the discrete version of the rotated rotator considered by Berry, the rotated standard map, we further explore this connection as well as the role of the geometric phase at the onset of chaos. Further into the chaotic regime, we show that the geometric phase is also related to the diffusive behaviour of the dynamical variables and the Lyapunov exponent. - Highlights: • We extend the concept of geometric phase to maps. • For the rotated sine circle map, we demonstrate an analytical relationship between the geometric phase and the rotation number. • For the rotated standard map, we explore the role of the geometric phase at the onset of chaos. • We show that the geometric phase is related to the diffusive behaviour of the dynamical variables and the Lyapunov exponent.

  7. Morphometrical and Topographical Anatomy of Position of Nutrient Foramen on Fully Ossified Left Femur

    Directory of Open Access Journals (Sweden)

    Tanvir Hossain Parash

    2013-05-01

    Full Text Available Background: The femur is the typical long bone of lower limb which extends from the pelvis to the knee. It forms the skeleton of the thigh, bears body weight, supports movement of legs; provide attachment to muscles, form blood cells and acts as a store house for calcium and phosphate. The nutrient foramina are cavities that conduct the nutrient arteries and the peripheral nerves. The majority blood supply for femur originates from the nutrient arteries, mainly during the growing period and during the early phase of ossification. In bone grafts the nutrient blood supply is crucial and it should be preserved in order to promote the fracture healing.Objective: The anatomy of nutrient foramen of femur is very essential for orthopedic & vascular surgeons as well as to radiologists for planning of treatment.Materials and method: This cross sectional study was carried out in the department of Anatomy, Sir Salimullah Medical College, Dhaka, Bangladesh from July 2011 to June 2012. The study comprised 199 fully ossified left sided dry femur of both sex (n=89 male, n=110 female. Sampling technique was purposive. Morphometric and topographic study was carried out on all samples by direct physical and photographic methods.Results: The most common position of nutrient foramen on the shaft of femur was found on the middle 1/5th in both male and female femur (50.78% in male and 56.86% in female respectively.Conclusion: The anatomical knowledge about this study might be useful in certain surgical procedures as well as micro vascular bone transfer to preserve the circulation.

  8. Geometric entanglement in the Laughlin wave function

    Science.gov (United States)

    Zhang, Jiang-Min; Liu, Yu

    2017-08-01

    We study numerically the geometric entanglement in the Laughlin wave function, which is of great importance in condensed matter physics. The Slater determinant having the largest overlap with the Laughlin wave function is constructed by an iterative algorithm. The logarithm of the overlap, which is a geometric quantity, is then taken as a geometric measure of entanglement. It is found that the geometric entanglement is a linear function of the number of electrons to a good extent. This is especially the case for the lowest Laughlin wave function, namely the one with filling factor of 1/3. Surprisingly, the linear behavior extends well down to the smallest possible value of the electron number, namely, N = 2. The constant term does not agree with the expected topological entropy. In view of previous works, our result indicates that the relation between geometric entanglement and topological entropy is very subtle.

  9. Geometric covers, graph orientations, counter games

    DEFF Research Database (Denmark)

    Berglin, Edvin

    2017-01-01

    Geometric Cover is a large family of NP-complete special cases of the broader Set Cover problem. Unlike the general problem, Geometric Cover involves objects that exist in a geometric setting, consequently implying that they are all restricted to obeying some inherent structure. The archetypal...... example is Line Cover, also known as Point-Line Cover, where a set of points in a geometric space are to be covered by placing a restricted number of lines. We present new FPT algorithms for the sub-family Curve Cover (which includes Line Cover), as well as for Hyperplane Cover restricted to R 3 (i.......e. Plane Cover), with improved time complexity compared to the previous best results. Our improvements are derived from a more careful treatment of the geometric properties of the covering objects than before, and invoking incidence bounds from pure geometry. An orientation of an un-directed graph...

  10. Extreme femoral valgus and patella dislocation following lateral plate fixation of a pediatric femur fracture.

    Science.gov (United States)

    Ezzat, Ahmed; Iobst, Christopher

    2016-07-01

    A 15-year-old boy presented with a 35° femoral valgus deformity, leg-length discrepancy, painful retained hardware, and a lateral dislocation of the patella 4 years after undergoing lateral plate fixation of a distal femur fracture. Femoral valgus is a possible complication of lateral plate fixation in up to 30% of pediatric distal femur fractures. With this patient's unusual combination of deformities as an example, we suggest early hardware removal after fracture union to prevent the development of deformity. If plate removal is not chosen, then continued close monitoring of the patient is necessary until skeletal maturity.

  11. Bilateral simultaneous neck femur fracture following domestic fall in an elderly patient: a rare case report

    Directory of Open Access Journals (Sweden)

    Mayank Vijayvargiya

    Full Text Available ABSTRACT Simultaneous bilateral neck femur fracture is a rare entity that has been associated with underlying bone disease, various metabolic diseases, high-energy trauma, and seizure disorders. Its occurrence following minimal trauma is very rare. This article presents the case of a 66-year-old female who sustained bilateral intracapsular fracture neck femur following a slip and fall at home. Single-stage bilateral cemented total hip replacement was done using a direct lateral approach with alternate right and left lateral positions. The authors report a satisfactory outcome, with Harris hip score of 98 at one year, which persisted until her last follow-up at 30 months.

  12. ASYMMETRICAL BILATERAL HIP DISLOCATION WITH SEGMENTAL FRACTURE FEMUR: AN UNUSUAL CASE REPORT AND LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    Ramesh

    2015-01-01

    Full Text Available Bilateral traumatic hip dislocation is rarely seen. A unique case is presented, consisting of asymmetric bilateral hip dislocation with associated segmental fracture femur, resulting from fall from bus. This case represents an unusual, severe combination of injuries resulting from the fall from bus under influence of alcohol. Traumatic hip dislocation represents a true orthopaedic emergency . Given the severity of associated complications, every effort should be made to ensure pr ompt diagnosis and immediate therapy. We report our experience in the management of this complex injury pattern and review the pertinent literature on this subject. Keywords: Bilateral hip dislocation , Asymmetric hip dislocation , Segmental femur fracture , Closed reduction , Fall from bus .

  13. Chronic Osteomyelitis of the Femur with Segmental Bone Defect: Concepts and Treatment

    Directory of Open Access Journals (Sweden)

    Mohd. Y. Bajuri

    2017-04-01

    Full Text Available Chronic osteomyelitis of the femur has always been a challenging scenario for the treating surgeon. It leads to morbidity to the patient as it interferes with the patient's rehabilitation and mobilisation. This is further complicated with the presence of a segmental bone loss following debridement due to the infection. We present a case of a young man who had a femur fracture which was initially treated with intramedullary nailing and subsequently was complicated with deep surgical site infection leading to chronic osteomyelitis.

  14. Femur ontogeny in humans and great apes: heterochronic implications for hominid évolution

    Science.gov (United States)

    Tardieu, Christine

    1997-12-01

    Did the first hominids have a short developmental period similar to that of the great apes, or a longer period closer to that of modern humans? Some morphological modifications undergone by the human femur during growth are shown to be excellent markers of different developmental stages. The femur of the first hominids ( Australopithecus afarensis) shows only features of infantile growth, whereas characters of both infantile and adolescent growth are typical of later hominids ( Homo). In the first australopithecines the period of peripubertal growth would have still been short. The prolongation of the adolescent period appears to be a characteristic of Homo.

  15. Case report 473: Tuberculosis of the distal metaphysis of the femur

    Energy Technology Data Exchange (ETDEWEB)

    Abdelwahab, I.F.; Gould, E.; Present, D.A.; Klein, M.J.; Nelson, J.

    1988-04-01

    In summary, a case of tuberculous osteomyelitis of the femur in a 16-month-old male child has been presented. The parents illegally immigrated to the United States from Central America before the birth of their child. Both parents had active pulmonary tuberculosis and the child presented with calcified granulomas in his lungs in addition to the lesion in the femur. This presentation is uncommon among the white population in the United States and Europe and is usually limited to non-white immigrants. (orig./SHA).

  16. The Reliability of Classifications of Proximal Femoral Fractures with 3-Dimensional Computed Tomography: The New Concept of Comprehensive Classification

    Directory of Open Access Journals (Sweden)

    Hiroaki Kijima

    2014-01-01

    Full Text Available The reliability of proximal femoral fracture classifications using 3DCT was evaluated, and a comprehensive “area classification” was developed. Eleven orthopedists (5–26 years from graduation classified 27 proximal femoral fractures at one hospital from June 2013 to July 2014 based on preoperative images. Various classifications were compared to “area classification.” In “area classification,” the proximal femur is divided into 4 areas with 3 boundary lines: Line-1 is the center of the neck, Line-2 is the border between the neck and the trochanteric zone, and Line-3 links the inferior borders of the greater and lesser trochanters. A fracture only in the first area was classified as a pure first area fracture; one in the first and second area was classified as a 1-2 type fracture. In the same way, fractures were classified as pure 2, 3-4, 1-2-3, and so on. “Area classification” reliability was highest when orthopedists with varying experience classified proximal femoral fractures using 3DCT. Other classifications cannot classify proximal femoral fractures if they exceed each classification’s particular zones. However, fractures that exceed the target zones are “dangerous” fractures. “Area classification” can classify such fractures, and it is therefore useful for selecting osteosynthesis methods.

  17. Finger Proximal Interphalangeal Joint Dislocation.

    Science.gov (United States)

    Ramponi, Denise; Cerepani, Mary Jo

    2015-01-01

    Finger dislocations are common injuries that are often managed by emergency nurse practitioners. A systematic physical examination following these injuries is imperative to avoid complications. Radiographic views, including the anteroposterior, lateral, and oblique views, are imperative to evaluate these finger dislocations. A dorsal dislocation of the proximal interphalangeal (PIP) joint is the most common finger dislocation type often easily reduced. A volar PIP dislocation can often be difficult to reduce and may result in finger deformity. Finger dislocations should be reduced promptly. Referral to an orthopedic hand specialist is required if the dislocation is unable to be reduced or if the finger joint is unstable following reduction attempts.

  18. Equilibrium properties of proximity effect

    Energy Technology Data Exchange (ETDEWEB)

    Esteve, D.; Pothier, H.; Gueron, S.; Birge, N.O.; Devoret, M.

    1996-12-31

    The proximity effect in diffusive normal-superconducting (NS) nano-structures is described by the Usadel equations for the electron pair correlations. We show that these equations obey a variational principle with a potential which generalizes the Ginzburg-Landau energy functional. We discuss simple examples of NS circuits using this formalism. In order to test the theoretical predictions of the Usadel equations, we have measured the density of states as a function of energy on a long N wire in contact with a S wire at one end, at different distances from the NS interface. (authors). 12 refs.

  19. The Hounsfield value for cortical bone geometry in the proximal humerus - an in vitro study

    Energy Technology Data Exchange (ETDEWEB)

    Lim Fat, Daren; Kennedy, Jim; Galvin, Rose; O' Brien, Fergal; Mc Grath, Frank; Mullett, Hannan [Royal College of Surgeons in Ireland, Investigations Carried Out at Anatomy Lab, Dublin (Ireland)

    2012-05-15

    Fractures of the proximal humerus represent a major osteoporotic burden. Recent developments in CT imaging have emphasized the importance of cortical bone thickness distribution in the prevention and management of fragility fractures. We aimed to experimentally define the CT density of cortical bone in the proximal humerus for building cortical geometry maps. With ethical approval, we used ten fresh-frozen human proximal humeri. These were stripped of all soft tissue and high-resolution CT images were then taken. The humeral heads were then subsequently resected to allow access to the metaphyseal area. Using curettes, cancellous bone was removed down to hard cortical bone. Another set of CT images of the reamed specimen was then taken. Using CT imaging software and a CAD interface, we then compared cortical contours at different CT density thresholds to the reference inner cortical contour of our reamed specimens. Working with 3D model representations of these cortical maps, we were able to accurately make distance comparison analyses based on different CT thresholds. We could compute a single closest value at 700 HU. No difference was found in the HU-based contours generated along the 500-900 HU pixels (p = 1.000). The contours were significantly different from those generated at 300, 400, 1,000, and 1,100 HU. A Hounsfield range of 500-900 HU can accurately depict cortical bone geometry in the proximal humerus. Thresholding outside this range leads to statistically significant inaccuracies. Our results concur with a similar range reported in the literature for the proximal femur. Knowledge of regional variations in cortical bone thickness has direct implications for basic science studies on osteoporosis and its treatment, but is also important for the orthopedic surgeon since our decision for treatment options is often guided by local bone quality. (orig.)

  20. [Partial and total joint replacement in femur head necrosis].

    Science.gov (United States)

    Fink, B; Rüther, W

    2000-05-01

    In literature, the results of hip arthroplasty in patients with avascular osteonecrosis of the femoral head vary. The main reason may be the nonhomogeneous patient groups concerning etiology of the femoral head necrosis (FHN). Analyzing the results of hip endoprosthesis in relation to the etiology of FHN leads to the assumption that steroid-induced FHN and FHN with underlying systemic bone diseases (renal osteodystrophy, sickle-cell hemoglobinopathy) have the highest loosening rates. Diseases with immunosuppressive medication and sickle-cell hemoglobinopathy have the highest risk of joint infection. Therefore etiology plays an important role in the long-term results of hip endoprostheses in FHN. Modern cement techniques of the second generation and new non-cemented total hip endoprostheses seem to have better results than older prostheses and cement techniques. We followed-up 52 non-cemented thrust plate prostheses in 45 patients with FHN, prospectively, for at least 2 years (3.7 +/- 1.6 years). The revision rate was 9.6% (two aseptic loosenings in one patient with renal osteodystrophy and one patient with alcohol abuse, as well as three late infections in one patient with alcohol abuse and two patients with renal osteodystrophy). Additionally, five prostheses showed radiologic lines of a minimum of 2 mm. Future studies with longer follow-up are needed to find out whether these prosthetic designs with proximal fixation of the femoral component preserving the diaphysial bone have advantages in young FHN patients.

  1. Fitting a geometric graph to a protein-protein interaction network.

    Science.gov (United States)

    Higham, Desmond J; Rasajski, Marija; Przulj, Natasa

    2008-04-15

    Finding a good network null model for protein-protein interaction (PPI) networks is a fundamental issue. Such a model would provide insights into the interplay between network structure and biological function as well as into evolution. Also, network (graph) models are used to guide biological experiments and discover new biological features. It has been proposed that geometric random graphs are a good model for PPI networks. In a geometric random graph, nodes correspond to uniformly randomly distributed points in a metric space and edges (links) exist between pairs of nodes for which the corresponding points in the metric space are close enough according to some distance norm. Computational experiments have revealed close matches between key topological properties of PPI networks and geometric random graph models. In this work, we push the comparison further by exploiting the fact that the geometric property can be tested for directly. To this end, we develop an algorithm that takes PPI interaction data and embeds proteins into a low-dimensional Euclidean space, under the premise that connectivity information corresponds to Euclidean proximity, as in geometric-random graphs. We judge the sensitivity and specificity of the fit by computing the area under the Receiver Operator Characteristic (ROC) curve. The network embedding algorithm is based on multi-dimensional scaling, with the square root of the path length in a network playing the role of the Euclidean distance in the Euclidean space. The algorithm exploits sparsity for computational efficiency, and requires only a few sparse matrix multiplications, giving a complexity of O(N(2)) where N is the number of proteins. The algorithm has been verified in the sense that it successfully rediscovers the geometric structure in artificially constructed geometric networks, even when noise is added by re-wiring some links. Applying the algorithm to 19 publicly available PPI networks of various organisms indicated that: (a

  2. Catastrophic cement reaction following cementation for megaprosthesis for proximal femoral fracture.

    Science.gov (United States)

    Baig, Muhammad Nouman; Curtin, William; Callaghan, Michael Andrew; Murphy, Colin G

    2017-09-23

    Bone cement implantation syndrome (BCIS) is a well-described and potentially fatal complication of orthopaedic surgery involving pressurised bone cement. Although also described for certain spinal procedures, it is most commonly associated with cemented hip and knee arthroplasty and with cemented hemiarthroplasty following neck of femur fracture in particular.Donaldson et alproposed the definition of BCIS as a syndrome "characterized by hypoxia, hypotension or both and/or unexpected loss of consciousness occurring around the time of cementation, prosthesis insertion, reduction of the joint or, occasionally, limb tourniquet deflation in a patient undergoing cemented bone surgery". Other features include increased vascular resistance, cardiac arrhythmias and cardiac arrest post cement use.We describe a case of a patient who suffered a catastrophic reaction to cement during surgery for a comminuted proximal femoral fracture. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  3. CGAlgebra: a Mathematica package for conformal geometric algebra

    OpenAIRE

    Aragon, Jose L.

    2017-01-01

    A tutorial of the Mathematica package CGAlgebra, for conformal geometric algebra calculations is presented. Using rule-based programming, the 5-dimensional conformal geometric algebra is implemented and defined functions simplify the calculations of geometric, outer and inner products, as well as many other calculations related with geometric transformations. CGAlgebra is available from https://github.com/jlaragonvera/Geometric-Algebra

  4. Six months of disuse during hibernation does not increase intracortical porosity or decrease cortical bone geometry, strength, or mineralization in black bear (Ursus americanus) femurs.

    Science.gov (United States)

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Bunnell, Kevin; Auger, Janene; Black, Hal L; Donahue, Seth W

    2009-07-22

    Disuse typically uncouples bone formation from resorption, leading to bone loss which compromises bone mechanical properties and increases the risk of bone fracture. Previous studies suggest that bears can prevent bone loss during long periods of disuse (hibernation), but small sample sizes have limited the conclusions that can be drawn regarding the effects of hibernation on bone structure and strength in bears. Here we quantified the effects of hibernation on structural, mineral, and mechanical properties of black bear (Ursus americanus) cortical bone by studying femurs from large groups of male and female bears (with wide age ranges) killed during pre-hibernation (fall) and post-hibernation (spring) periods. Bone properties that are affected by body mass (e.g. bone geometrical properties) tended to be larger in male compared to female bears. There were no differences (p>0.226) in bone structure, mineral content, or mechanical properties between fall and spring bears. Bone geometrical properties differed by less than 5% and bone mechanical properties differed by less than 10% between fall and spring bears. Porosity (fall: 5.5+/-2.2%; spring: 4.8+/-1.6%) and ash fraction (fall: 0.694+/-0.011; spring: 0.696+/-0.010) also showed no change (p>0.304) between seasons. Statistical power was high (>72%) for these analyses. Furthermore, bone geometrical properties and ash fraction (a measure of mineral content) increased with age and porosity decreased with age. These results support the idea that bears possess a biological mechanism to prevent disuse and age-related osteoporoses.

  5. A Geometrical View of Higgs Effective Theory

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    A geometric formulation of Higgs Effective Field Theory (HEFT) is presented. Experimental observables are given in terms of geometric invariants of the scalar sigma model sector such as the curvature of the scalar field manifold M. We show how the curvature can be measured experimentally via Higgs cross-sections, W_L scattering, and the S parameter. The one-loop action of HEFT is given in terms of geometric invariants of M. The distinction between the Standard Model (SM) and HEFT is whether M is flat or curved, with the curvature a signal of the scale of new physics.

  6. 3D Architecture of Trabecular Bone in the Pig Mandible and Femur: Inter-Trabecular Angle Distributions.

    Science.gov (United States)

    Ben-Zvi, Yehonatan; Reznikov, Natalie; Shahar, Ron; Weiner, Steve

    2017-09-01

    Cancellous bone is an intricate network of interconnected trabeculae, to which analysis of network topology can be applied. The inter-trabecular angle (ITA) analysis - an analysis of network topological parameters and regularity of network-forming nodes, was previously carried out on human proximal femora and showed that trabecular bone follows two main principles: sparsity of the network connectedness (prevalence of nodes with low connectivity in the network) and maximal space spanning (angular offset of connected elements is maximal for their number and approximates the values of geometrically symmetric shapes). These observations suggest that 3D organization of trabecular bone, irrespective of size and shape of individual elements, reflects a tradeoff between minimal metabolic cost of maintenance and maximal network stability under conditions of multidirectional loading. In this study we validate the ITA application using additional 3D structures (cork and 3D-printed metal lattices), analyze the ITA parameters in porcine proximal femora and mandibles and carry out a spatial analysis of the most common node type in the porcine mandibular condyle. The validation shows that the ITA application reliably detects designed or evolved topological parameters. The ITA parameters of porcine trabecular bones are similar to those of human bones. We demonstrate functional adaptation in the pig mandibular condyle by showing that the planar nodes with 3 edges are preferentially aligned in relation to the muscle forces that are applied to the condyle. We conclude that the ITA topological parameters are remarkable conserved, but locally do adapt to applied stresses.

  7. Evaluation of cortical index in the femur of young adults in Port ...

    African Journals Online (AJOL)

    There was no significant difference between the index of the males and females. This study provides an easy and objective means of diagnosing and assessing osteoporosis but can not be used for gender identification of long bone in anthropological research. Keywords: Femur, Cortical Index, Osteoporosis, Radiograph ...

  8. A PTH-responsive circadian clock operates in ex vivo mouse femur fracture healing site.

    Science.gov (United States)

    Kunimoto, Tatsuya; Okubo, Naoki; Minami, Yoichi; Fujiwara, Hiroyoshi; Hosokawa, Toshihiro; Asada, Maki; Oda, Ryo; Kubo, Toshikazu; Yagita, Kazuhiro

    2016-02-29

    The circadian clock contains clock genes including Bmal1 and Period2, and it maintains an interval rhythm of approximately 24 hours (the circadian rhythm) in various organs including growth plate and articular cartilage. As endochondral ossification is involved not only in growth plate but also in fracture healing, we investigated the circadian clock functions in fracture sites undergoing healing. Our fracture models using external fixation involved femurs of Period2::Luciferase knock-in mice which enables the monitoring of endogenous circadian clock state via bioluminescence. Organ culture was performed by collecting femurs, and fracture sites were observed using bioluminescence imaging systems. Clear bioluminescence rhythms of 24-hour intervals were revealed in fracture healing sites. When parathyroid hormone (PTH) was administered to fractured femurs in organ culture, peak time of Period2::Luciferase activity in fracture sites and growth plates changed, indicating that PTH-responsive circadian clock functions in the mouse femur fracture healing site. While PTH is widely used in treating osteoporosis, many studies have reported that it contributes to improvement of fracture healing. Future studies of the role of this local clock in wound healing may reveal a novel function of the circadian timing mechanism in skeletal cells.

  9. Case-only designs for studying the association of antidepressants and hip or femur fracture.

    NARCIS (Netherlands)

    Groot, M.C.H. de; Candore, G.; Uddin, M.J.; Souverein, P.C.; Ali, M.S.; Belitser, S.V.; Huerta, C.; Groenwold, R.H.H.; Alvarez, Y.; Slattery, J.; Korevaar, J.; Hoes, A.W.; Roes, K.C.B.; Boer, A. de; Douglas, I.J.; Schlienger, R.G.; Reynolds, R.; Klungel, O.H.; Gardarsdottir, H.

    2016-01-01

    Purpose: The purpose of this study is to evaluate the performance and validity of the case-crossover (CCO) and self-controlled case-series (SCCS) designs when studying the association between hip/femur fracture (HF) and antidepressant (AD) use in general practitioner databases. In addition,

  10. The effect of distal femur bony morphology on in vivo knee translational and rotational kinematics.

    Science.gov (United States)

    Hoshino, Yuichi; Wang, Joon Ho; Lorenz, Stephan; Fu, Freddie H; Tashman, Scott

    2012-07-01

    Tibio-femoral kinematics are clearly influenced by the bony morphology of the femur. Previous morphological studies have not directly evaluated relationships between morphology and knee kinematics. Therefore, the purpose of this study was to examine the relationship between distal femur bony morphology and in vivo knee kinematics during running. It was hypothesized that the posterior offset of the transcondylar axis would be related to the magnitude of anterior/posterior tibio-femoral translation and that the rotational angle of the transcondylar axis would be related to the magnitude of internal/external knee rotation. Seventeen contralateral (uninjured) knees of ACL-reconstructed patients were used. Distal femoral geometry was analyzed from 3D-CT data by determining the anteroposterior location (condyle offset ratio--COR) and rotational angle (condylar twist angle--CTA) of the femoral transcondylar axis. Six degree-of-freedom knee kinematics were obtained during running using a dynamic stereo radiograph system. Knee kinematics were correlated with the femoral morphologic measures (COR and CTA) to investigate the influence of femoral geometry on dynamic knee function. Significant correlations were identified between distal femur morphology and knee kinematics. Anterior tibial translation was positively correlated with the condyle offset ratio (R(2) = 0.41, P femur shape on dynamic knee function. III.

  11. Adaptation of the lateral distal femur DXA scan technique to adults with disabilities.

    Science.gov (United States)

    Henderson, Richard C; Henderson, Brent A; Kecskemethy, Heidi H; Hidalgo, Sebastian T; Nikolova, Beth Ann; Sheridan, Kevin; Harcke, H Theodore; Thorpe, Deborah E

    2015-01-01

    The technique that best addresses the challenges of assessing bone mineral density in children with neuromuscular impairments is a dual-energy X-ray absorptiometry (DXA) scan of the lateral distal femur. The purpose of this study was to adapt this technique to adults with neuromuscular impairments and to assess the reproducibility of these measurements. Thirty-one adults with cerebral palsy had both distal femurs scanned twice, with the subject removed and then repositioned between each scan (62 distal femurs, 124 scans). Each scan was independently analyzed twice by 3 different technologists of varying experience with DXA (744 analyses). Precision of duplicate analyses of the same scan was good (range: 0.4%-2.3%) and depended on both the specific region of interest and the experience of the technologist. Precision was reduced when comparing duplicate scans, ranging from 7% in the metaphyseal (cancellous) region to 2.5% in the diaphyseal (cortical) region. The least significant change was determined as recommended by the International Society for Clinical Densitometry for each technologist and each region of interest. Obtaining reliable, reproducible, and clinically relevant assessments of bone mineral density in adults with neuromuscular impairments can be challenging. The technique of obtaining DXA scans of the lateral distal femur can be successfully applied to this population but requires a commitment to developing the necessary expertise. Copyright © 2015 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  12. Does Computer-Assisted Femur First THR Improve Musculoskeletal Loading Conditions?

    NARCIS (Netherlands)

    Weber, Tim A.; Dendorfer, Sebastian; Grifka, Joachim; Verkerke, Gijsbertus J.; Renkawitz, Tobias

    2015-01-01

    We have developed a novel, computer-assisted operation method for minimal-invasive total hip replacement (THR) following the concept of " femur first/combined anteversion," which incorporates various aspects of performing a functional optimization of the prosthetic stem and cup position (CAS FF).

  13. Case-only designs for studying the association of antidepressants and hip or femur fracture

    NARCIS (Netherlands)

    De Groot, Mark C H; Candore, Gianmario; Uddin, Md Jamal; Souverein, Patrick C.; Ali, M. Sanni; Belitser, Svetlana V.; Huerta, Consuelo; Groenwold, Rolf H H; Alvarez, Yolanda; Slattery, Jim; Korevaar, Joke; Hoes, Arno W.; Roes, Kit C B; de Boer, Anthonius; Douglas, Ian J.; Schlienger, Raymond G.; Reynolds, Robert; Klungel, Olaf H.; Gardarsdottir, Helga

    2016-01-01

    PURPOSE: The purpose of this study is to evaluate the performance and validity of the case-crossover (CCO) and self-controlled case-series (SCCS) designs when studying the association between hip/femur fracture (HF) and antidepressant (AD) use in general practitioner databases. In addition,

  14. Case-only designs for studying the association of antidepressants and hip or femur fracture

    NARCIS (Netherlands)

    De Groot, Mark C. H.; Candore, Gianmario; Uddin, Jamal; Souverein, Patrick; Ali, M. Sanni; Belitser, S.; Huerta, Consuelo; Groenwold, Rolf H. H.; Alvarez, Yolanda; Slattery, Jim; Korevaar, Joke; Hoes, Arno W.; Roes, Kit C. B.; de Boer, Anthonius; Douglas, Ian J.; Schlienger, Raymond G.; Reynolds, Robert; Klungel, Olaf H.; Gardarsdottir, Helga

    2016-01-01

    Purpose: The purpose of this study is to evaluate the performance and validity of the case-crossover (CCO) and self-controlled case-series (SCCS) designs when studying the association between hip/femur fracture (HF) and antidepressant (AD) use in general practitioner databases. In addition,

  15. Bone Morphology in 46 BXD Recombinant Inbred Strains and Femur-Tibia Correlation

    Directory of Open Access Journals (Sweden)

    Yueying Zhang

    2015-01-01

    Full Text Available We examined the bone properties of BXD recombinant inbred (RI mice by analyzing femur and tibia and compared their phenotypes of different compartments. 46 BXD RI mouse strains were analyzed including progenitor C57BL/6J (n=16 and DBA/2J (n=15 and two first filial generations (D2B6F1 and B6D2F1. Strain differences were observed in bone quality and structural properties (P<0.05 in each bone profile (whole bone, cortical bone, or trabecular bone. It is well known that skeletal phenotypes are largely affected by genetic determinants and genders, such as bone mineral density (BMD. While genetics and gender appear expectedly as the major determinants of bone mass and structure, significant correlations were also observed between femur and tibia. More importantly, positive and negative femur-tibia associations indicated that genetic makeup had an influence on skeletal integrity. We conclude that (a femur-tibia association in bone morphological properties significantly varies from strain to strain, which may be caused by genetic differences among strains, and (b strainwise variations were seen in bone mass, bone morphology, and bone microarchitecture along with bone structural property.

  16. Implant failure caused by non-union of bisphosphonate-associated subtrochanteric femur fracture.

    LENUS (Irish Health Repository)

    O'Neill, Barry James

    2014-04-03

    Bisphosphonate use has been identified as a contributory factor in atypical subtrochanteric fracture of the femur. These fractures are commonly treated with an intramedullary device. We present a case of implant failure of an intrameduallary device caused by non-union of an atypical subtrochanteric fracture.

  17. J-splint use for temporizing management of pediatric femur fractures: a review of 18 cases.

    Science.gov (United States)

    Ritterman, Scott A; Daniels, Alan H; Kane, Patrick M; Eberson, Craig P; Born, Christopher T

    2014-08-01

    Pediatric femoral fractures are common injuries encountered in the field and in emergency departments. Currently described temporizing management strategies include skeletal traction, skin traction, traction splinting, and posterior splinting, all of which are suboptimal in some instances. J-splinting femur fractures may be advantageous in temporizing management of pediatric femur fractures. The objective of this study was to evaluate the safety and effectiveness of J-splint use for temporizing management of pediatric femur fractures. This study used a retrospective review of 18 pediatric patients with femur fractures treated with J-splinting in the emergency department. Patient age, weight, and presplinting and postsplinting pain scale ratings were recorded, as well as presplint and postsplint anteroposterior and lateral radiographic fracture angulation. Pain before and after J-splinting was compared using a paired t test. The mean age of this cohort was 5.4 years (range, 6 months-13 y), with a mean weight of 21.1 kg (range, 7.7-57 kg). In this cohort, there was a significant reduction in pain after reduction and splinting from a mean of 6 to a mean of 1 (P < 0.001). No significant difference in fracture alignment was noted after J-splinting. No complications were noted. The J-splint is a reliable, simple, and rapidly applied splint that prevents many of the complications and downfalls of other described temporizing measures and helps to provide excellent pain management in the acute setting.

  18. anthropometry of the distal femur in a kenyan population and its ...

    African Journals Online (AJOL)

    Conclusion: The dimensions of the distal femur of the adult Kenyan differs from other ethnic populations. Of the implants sampled, most had dimensions that did not closely match those of the femora studied. Local clinical studies are needed to determine the clinical significance of the mismatch on the outcome of total knee.

  19. Anthropometry of the distal femur in a Kenyan population and its ...

    African Journals Online (AJOL)

    Conclusion: The dimensions of the distal femur of the adult Kenyan differs from other ethnic populations. Of the implants sampled, most had dimensions that did not closely match those of the femora studied. Local clinical studies are needed to determine the clinical significance of the mismatch on the outcome of total knee ...

  20. INTRACAPSULAR FRACTURE OF NECK OF FEMUR (IC#NF - OSTEOSYNTHESIS BY CANNULATED CANCELLOUS SCREW FIXATION

    Directory of Open Access Journals (Sweden)

    L. Lokanadha Rao

    2016-09-01

    Full Text Available Fractures of neck of femur have always presented great challenges to the orthopaedic surgeons. This remains, even today, an unsolved fracture as far as treatment and results are concerned. Results depend upon the extent of injury, timing of surgery and adequacy of reduction and fixation. Fixation with cannulated cancellous screws is usually adequate for femoral neck fractures. Lateral cortex plays a very important role in screw fixation. AIMS AND OBJECTIVES To study the effectiveness of cannulated cancellous screw fixation for treatment of fracture of neck of femur in adults. MATERIALS AND METHODS This study was conducted at Andhra Medical College, King George Hospital, Visakhapatnam, AP from Nov 2013 to Oct 2015. The patients with intracapsular fracture of neck of femur are evaluated with pre-operative X-rays of pelvis with both hips and X-ray of the concerned hip joint both in anteroposterior and lateral views and their outcome was evaluated postoperatively after fixation with cancellous screws. The outcome is evaluated in terms of pain relief, extent of ambulation achieved after surgery. The classifications we followed are Pauwel’s and Garden’s classification of fracture of neck of femur. The patients were followed up to one year to assess the functional outcome. OBSERVATION AND RESULTS A good result was obtained in 66.1% of the patients, excellent in 23.2%, fair in 3.8% and poor result in 6.9% of the patients. Complications such as Non-union & avascular necrosis in one case, Non-union and Extrusion of screws in one case, Cut through of screws into articular surface leading to painful joint in one case. Most of the cases of intracapsular neck of femur were in the age group of 31-40 years. There was male preponderance as shown in this study (69%. CONCLUSION By the usage of multiple cannulated cancellous lag screws, compression effect at the fracture site is achieved, it also avoids re-displacement and rotations. The implant occupies less