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Femoral Fractures (femoral + fractures)
Selected AbstractsPERIPROSTHETIC FEMORAL FRACTURES: A GROWING BUT POTENTIALLY AVOIDABLE PROBLEM?ANZ JOURNAL OF SURGERY, Issue 6 2007FAOrthA, FRACS, Peter Choong MD No abstract is available for this article. [source] Modulation of Wnt signaling influences fracture repairJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 7 2010David E. Komatsu Abstract While the importance of Wnt signaling in skeletal development and homeostasis is well documented, little is known regarding its function in fracture repair. We hypothesized that activation and inactivation of Wnt signaling would enhance and impair fracture repair, respectively. Femoral fractures were generated in Lrp5 knockout mice (Lrp5,/,) and wild-type littermates (Lrp5+/+), as well as C57BL/6 mice. Lrp5,/, and Lrp5+/+ mice were untreated, while C57BL/6 mice were treated 2×/week with vehicle or anti-Dkk1 antibodies (Dkk1 Ab) initiated immediately postoperatively (Day 0) or 4 days postoperatively (Day 4). Fractures were radiographed weekly until sacrifice at day 28, followed by DXA, pQCT, and biomechanical analyses. Lrp5,/, mice showed impaired repair compared to Lrp5+/+ mice, as evidenced by reduced callus area, BMC, BMD, and biomechanical properties. The effects of Dkk1 Ab treatment depended on the timing of initiation. Day 0 initiation enhanced repair, with significant gains seen for callus area, BMC, BMD, and biomechanical properties, whereas Day 4 initiation had no effect. These results validated our hypothesis that Wnt signaling influences fracture repair, with prompt activation enhancing repair and inactivation impairing it. Furthermore, these data suggest that activation of Wnt signaling during fracture repair may have clinical utility in facilitating fracture repair. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:928,936, 2010 [source] Enhanced Chondrogenesis and Wnt Signaling in PTH-Treated Fractures,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2007Sanjeev Kakar Abstract Studies have shown that systemic PTH treatment enhanced the rate of bone repair in rodent models. However, the mechanisms through which PTH affects bone repair have not been elucidated. In these studies we show that PTH primarily enhanced the earliest stages of endochondral bone repair by increasing chondrocyte recruitment and rate of differentiation. In coordination with these cellular events, we observed an increased level of canonical Wnt-signaling in PTH-treated bones at multiple time-points across the time-course of fracture repair, supporting the conclusion that PTH responses are at least in part mediated through Wnt signaling. Introduction: Since FDA approval of PTH [PTH(1,34); Forteo] as a treatment for osteoporosis, there has been interest in its use in other musculoskeletal conditions. Fracture repair is one area in which PTH may have a significant clinical impact. Multiple animal studies have shown that systemic PTH treatment of healing fractures increased both callus volume and return of mechanical competence in models of fracture healing. Whereas the potential for PTH has been established, the mechanism(s) by which PTH produces these effects remain elusive. Materials and Methods: Closed femoral fractures were generated in 8-wk-old male C57Bl/6 mice followed by daily systemic injections of either saline (control) or 30 ,g/kg PTH(1,34) for 14 days after fracture. Bones were harvested at days 2, 3, 5, 7, 10, 14, 21, and 28 after fracture and analyzed at the tissue level by radiography and histomorphometry and at the molecular and biochemical levels level by RNase protection assay (RPA), real-time PCR, and Western blot analysis. Results: Quantitative ,CT analysis showed that PTH treatment induced a larger callus cross-sectional area, length, and total volume compared with controls. Molecular analysis of the expression of extracellular matrix genes associated with chondrogenesis and osteogenesis showed that PTH treated fractures displayed a 3-fold greater increase in chondrogenesis relative to osteogenesis over the course of the repair process. In addition, chondrocyte hypertrophy occurred earlier in the PTH-treated callus tissues. Analysis of the expression of potential mediators of PTH actions showed that PTH treatment significantly induced the expression of Wnts 4, 5a, 5b, and 10b and increased levels of unphosphorylated, nuclear localized ,-catenin protein, a central feature of canonical Wnt signaling. Conclusions: These results showed that the PTH-mediated enhancement of fracture repair is primarily associated with an amplification of chondrocyte recruitment and maturation in the early fracture callus. Associated with these cellular effects, we observed an increase in canonical Wnt signaling supporting the conclusion that PTH effects on bone repair are mediated at least in part through the activation of Wnt-signaling pathways. [source] A biomechanical study on flexible intramedullary nails used to treat pediatric femoral fracturesJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2005Jason K. Green Abstract Flexible intramedullary nails have been indicated to treat femoral fractures in pediatric patients. The purpose of this study was to examine the stability of simulated transverse fractures after retrograde intramedullary flexible nail fixation. Various nail diameter combinations were tested using composite femurs in bending, torsion, and a combined axial/bending test where a vertical compressive force was applied to the femoral head. The cross-sectional percent area fill of the nails within the femurs was also determined. In 4 point bending, the greatest repair stiffness was 12% of the intact stiffness. In torsion, the greatest stiffness was 1% of the intact stiffness for either internal or external rotation. The greatest repair stiffness was 80% of the intact stiffness for a compressive load applied to the femoral head. Nail combinations with single nail diameters greater than 40% of the mid-shaft canal width, as measured from an AP radiograph, prevented the fracture from being reduced and left a posterior gap. Flexible intramedullary nails may be of value in the treatment of pediatric femoral fractures, but care must be taken to insert nails that are correctly sized for the canal and to protect the healing fracture from high torsional and bending loads. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Age and ovariectomy impair both the normalization of mechanical properties and the accretion of mineral by the fracture callus in ratsJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2001Ralph A. Meyer Jr. The impact of age and ovariectomy on the healing of femoral fractures was studied in three groups of female rats at 8, 32 and 50 weeks of age at fracture. In the two older groups, the rats had been subjected to ovariectomy or sham surgery at random at 26 weeks of age. At fracture, all rats received unilateral intramedullary pinning of one femur and a middiaphyseal fracture. Rigidity and breaking load of the femora were evaluated at varying times up to 24 weeks after fracture induction by three-point bending to failure. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. In the youngest group, 8-week-old female rats regained normal femoral rigidity and breaking load by 4 weeks after fracture. They exceeded normal contralateral values by 8 weeks after fracture. In the middle group, at 32 weeks of age, fractures were induced, and the femora were harvested at 6 and 12 weeks after fracture. At 6 weeks after fracture there was partial restoration of rigidity and breaking load. At 12 weeks after fracture, only the sham-operated rats had regained normal biomechanical values in their fractured femora, while the fractured femora of the ovariectomized rats remained significantly lower in both rigidity and breaking load. In contrast, for the oldest group of rats, 50 weeks old at fracture, neither sham-operated nor ovariectomized rats regained normal rigidity or breaking load in their fractured femora within the 24 weeks in which they were studied. In all fractured bones, there was a significant increase in BMD over the contralateral intact femora due to the increased bone tissue and bone mineral in the fracture callus. Ovariectomy significantly reduced the BMD of the intact femora and also reduced the gain in BMD by the fractured femora. In conclusion, age and ovariectomy significantly impair the process of fracture healing in female rats as judged by measurements of rigidity and breaking load in three-point bending and by accretion of mineral into the fracture callus. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Slipped capital femoral epiphysis in dogsJOURNAL OF SMALL ANIMAL PRACTICE, Issue 12 2004A. P. Moores In a retrospective review of 43 femoral fractures, three dogs had separation of the femoral capital epiphysis from the metaphysis in the absence of trauma. Two of these dogs also had evidence of pathology in the contralateral femoral neck including, in one dog, displacement of the capital epiphysis in relation to the metaphysis without actual separation. The case histories, radiographic features and histopathological findings of these cases were reviewed and compared with previous cases of slipped capital femoral epiphysis (SCFE) reported in dogs and also with SCFE in children. Pre-slip, acute, chronic and acute-on-chronic slips were identified. Based on the cases reviewed, the authors advise internal fixation of stable slipped epiphyses in dogs. This may also be appropriate for unstable separations, although resorption of the femoral neck may preclude stable fixation and necessitate femoral head and neck excision. [source] Anaesthesia for proximal femoral fracture in the UK: first report from the NHS Hip Fracture Anaesthesia Network,ANAESTHESIA, Issue 3 2010S. M. White Summary The aim of this audit was to investigate process, personnel and anaesthetic factors in relation to mortality among patients with proximal femoral fractures. A questionnaire was used to record standardised data about 1195 patients with proximal femoral fracture admitted to 22 hospitals contributing to the Hip Fracture Anaesthesia Network over a 2-month winter period. Patients were demographically similar between hospitals (mean age 81 years, 73% female, median ASA grade 3). However, there was wide variation in time from admission to operation (24,108 h) and 30-day postoperative mortality (2,25%). Fifty percent of hospitals had a mean admission to operation time < 48 h. Forty-two percent of operations were delayed: 51% for organisational; 44% for medical; and 4% for ,anaesthetic' reasons. Regional anaesthesia was administered to 49% of patients (by hospital, range = 0,82%), 51% received general anaesthesia and 19% of patients received peripheral nerve blockade. Consultants administered 61% of anaesthetics (17,100%). Wide national variations in current management of patients sustaining proximal femoral fracture reflect a lack of research evidence on which to base best practice guidance. Collaborative audits such as this provide a robust method of collecting such evidence. [source] Comparison of external jugular and central venous pressures in patients undergoing repair of proximal femoral fracturesANAESTHESIA, Issue 10 2002C. M. Allsager No abstract is available for this article. [source] | ||||||||||