Dataset Information

A micro-architectural evaluation of osteoporotic human femoral heads to guide implant placement in proximal femoral fractures.

ABSTRACT: BACKGROUND AND PURPOSE: The micro-architecture of bone has been increasingly recognized as an important determinant of bone strength. Successful operative stabilization of fractures depends on bone strength. We evaluated the osseous micro-architecture and strength of the osteoporotic human femoral head. MATERIAL AND METHODS: 6 femoral heads, obtained during arthroplasty surgery for femoral neck fracture, underwent micro-computed tomography (microCT) scanning at 30 ?m, and bone volume ratio (BV/TV), trabecular thickness, structural model index, connection density, and degree of anisotropy for volumes of interest throughout the head were derived. A further 15 femoral heads underwent mechanical testing of compressive failure stress of cubes of trabecular bone from different regions of the head. RESULTS: The greatest density and trabecular thickness was found in the central core that extended from the medial calcar to the physeal scar. This region also correlated with the greatest degree of anisotropy and proportion of plate-like trabeculae. In the epiphyseal region, the trabeculae were organized radially from the physeal scar. The weakest area was found at the apex and peripheral areas of the head. The strongest region was at the center of the head. INTERPRETATION: The center of the femoral head contained the strongest trabecular bone, with the thickest, most dense trabeculae. The apical region was weaker. From an anatomical and mechanical point of view, implants that achieve fixation in or below this central core may achieve the most stable fixation during fracture healing.

SUBMITTER: Jenkins PJ

PROVIDER: S-EPMC3822129 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A micro-architectural evaluation of osteoporotic human femoral heads to guide implant placement in proximal femoral fractures.

Jenkins Paul J PJ Ramaesh Rishikesan R Pankaj Pankaj P Patton James T JT Howie Colin R CR Goffin Jérôme M JM Merwe Andrew van der Av Wallace Robert J RJ Porter Daniel E DE Simpson A Hamish AH

Acta orthopaedica 20130916 5

<h4>Background and purpose</h4>The micro-architecture of bone has been increasingly recognized as an important determinant of bone strength. Successful operative stabilization of fractures depends on bone strength. We evaluated the osseous micro-architecture and strength of the osteoporotic human femoral head.<h4>Material and methods</h4>6 femoral heads, obtained during arthroplasty surgery for femoral neck fracture, underwent micro-computed tomography (microCT) scanning at 30 μm, and bone volum ...[more]

PMID: 24032522

Similar Datasets

Project description:Osteoporosis is the consequence of altered bone metabolism resulting in the systemic reduction of bone strength and increased risk of fragility fractures. MicroRNAs (miRNAs) regulate gene expression on a post-transcriptional level are known to take part in the control of bone formation and bone resorption. Recently, targeted secretion of miRNAs from cells originating from various tissues has been described, which allows for their minimal-invasive detection in serum/plasma and use as biomarkers for presence and progression of pathological conditions. One pilot study has reported circulating miRNAs in serum and tissue of fracture patients. However, further studies are required to explore whether a dysbalance in bone homeostasis of fracture patients can reliably be reflected by specific circulating miRNAs, and whether these miRNAs might serve as drugable targets. Here, we report results from a comprehensive multiplex study of 175 miRNAs in serum samples obtained from 7 patients with osteoporotic fractures at the femoral neck, and 7 age-matched controls. Following elaborate quality control statistical analysis of this exploratory dataset identified 9 microRNAs with altered serum levels in response to fracture (adjusted p-value < 0.1). Of these, hsa-miR-10a/b gave excellent discrimination of both groups (AUC = 1.0), and clustering of samples based on the top10 miRNAs confirmed the high discriminatory power of circulating microRNAs for osteoporotic fractures. In the next step 3 miRNAs with unknown roles in osteogenic differentiation and 4 miRNA from a previous study were tested for their effects on osteogenic differentiation. Of these, 3 miRNAs showed robust effects on osteogenic differentiation. Overall, these data provide important insights into changes in serum miRNA in post-traumatic patients. Future studies will show, whether this knowledge can be used to improve current diagnostic methodologies to predict fracture risk and design novel treatment strategies for osteoporosis patients. Two groups with n=7 per group; one groups represents cases with osteoporotic fractures, the control group is age-matched without fractures

Project description:Insertion of bone substitution materials accelerates healing of osteoporotic fractures. Biodegradable materials are preferred for application in osteoporotic patients to avoid a second surgery for implant replacement. Degraded implant fragments are often absorbed by macrophages that are removed from the fracture side via passage through veins or lymphatic vessels. We investigated if lymphatic vessels occur in osteoporotic bone defects and whether they are regulated by the use of different materials. To address this issue osteoporosis was induced in rats using the classical method of bilateral ovariectomy and additional calcium and vitamin deficient diet. In addition, wedge-shaped defects of 3, 4, or 5 mm were generated in the distal metaphyseal area of femur via osteotomy. The 4 mm defects were subsequently used for implantation studies where bone substitution materials of calcium phosphate cement, composites of collagen and silica, and iron foams with interconnecting pores were inserted. Different materials were partly additionally functionalized by strontium or bisphosphonate whose positive effects in osteoporosis treatment are well known. The lymphatic vessels were identified by immunohistochemistry using an antibody against podoplanin. Podoplanin immunopositive lymphatic vessels were detected in the granulation tissue filling the fracture gap, surrounding the implant and growing into the iron foam through its interconnected pores. Significant more lymphatic capillaries were counted at the implant interface of composite, strontium and bisphosphonate functionalized iron foam. A significant increase was also observed in the number of lymphatics situated in the pores of strontium coated iron foam. In conclusion, our results indicate the occurrence of lymphatic vessels in osteoporotic bone. Our results show that lymphatic vessels are localized at the implant interface and in the fracture gap where they might be involved in the removal of lymphocytes, macrophages, debris and the implants degradation products. Therefore the lymphatic vessels are involved in implant integration and fracture healing.

Project description:ContextFemoral shaft cortical thickening has been mentioned in reports of atypical subtrochanteric and diaphyseal (S/D) femur fractures, but it is unclear whether thickening precedes fracture or results from a preceding stress fracture and what role bisphosphonates might play in cortical thickening.ObjectiveOur objective was to examine the relationship of cortical thickness to S/D fracture risk as well as establish normal reference values for femoral cortical thickness in a large population-based cohort of older women.DesignUsing pelvic radiographs obtained in 1986-1988, we measured femoral shaft cortical thickness 3 cm below the lesser trochanter in women in the Study of Osteoporotic Fractures. We measured this in a random sample and in those with S/D fractures and femoral neck and intertrochanteric fractures. Low-energy S/D fractures were identified from review of radiographic reports obtained between 1986 and 2010. Radiographs to evaluate atypia were not available. Analysis used case-cohort, proportional hazards models.OutcomesCortical thickness as a risk factor for low-energy S/D femur fractures as well as femoral neck and intertrochanteric fractures in the Study of Osteoporotic Fractures, adjusting for age and bone mineral density in proportional hazards models.ResultsAfter age adjustment, women with thinner medial cortices were at a higher risk of S/D femur fracture, with a relative hazard of 3.94 (95% confidence interval = 1.23-12.6) in the lowest vs. highest quartile. Similar hazard ratios were seen for femoral neck and intertrochanteric fractures. Medial or total cortical thickness was more strongly related to fracture risk than lateral cortical thickness.ConclusionsIn primarily bisphosphonate-naive women, we found no evidence that thick femoral cortices placed women at higher risk for low-energy S/D femur fractures; in fact, the opposite was true. Women with thin cortices were also at a higher risk for femoral neck and intertrochanteric fractures. Whether cortical thickness among bisphosphonate users plays a role in atypical S/D fractures remains to be determined.

Project description:IntroductionWe hypothesised that the use of a polyaxial locking plate design offers the same clinical benefits as a monoaxial locking plate system following distal femoral osteoporotic/periprosthetic fracture fixation.MethodA multicentre prospective randomised pilot trial was conducted. Inclusion criteria were patients over 60 years with a displaced osteoporotic or periprosthetic distal femoral fracture. Details documented included time to union, complications, reinterventions and functional outcomes according to the Oxford knee score and EuroQol EQ-5D. Analysis of factors influencing an early fracture healing response was performed between those with clear features of radiological callus formation at three months. Statistical analysis was performed using a logistic regression model with multiple covariates assessed for each plate system (1:1 ratio) over a follow-up period of one year.ResultsForty patients (34 females) with a mean age of 77 (60-99) were recruited. Four patients deceased within the first six months. Twenty-five patients united by the six month follow-up. Six more patients progressed to union between six and nine months. Five patients developed non-union (two patients had implant failure; one in each group) and all underwent revision surgery. Malunion was evident in two cases, one with 15° of valgus (monoaxial plate), and one with 12° of recurvatum (polyaxial plate). Between the two plate systems, statistical analysis revealed no significant differences in most of the recorded parameters. Radiological features of early bone healing were present when the surgical approach was smaller (p = 0.015), and when a greater working length of the bridging plate was present (p = 0.016).ConclusionBoth plate systems demonstrated good union rates and limited implant related complications. Good reduction, mechanically sound construct and respect of the local fracture biology was more important than the particular plate design characteristics.

Project description:BackgroundAlthough many treatments for ipsilateral proximal and shaft femoral fractures have been developed, controversy exists regarding their optimal management. The purpose of this retrospective study was to discuss the effectiveness of the bridge-link type combined fixation system (BCFS) and evaluate functional outcomes in treating patients with these complex fractures.Patients and methodsWe retrospectively reviewed 14 cases of ipsilateral proximal and shaft femoral fractures treated from January 2012 to December 2016. All cases were treated by BCFS combined with minimally invasive percutaneous plate osteosynthesis (MIPPO). Clinical and radiographic data were collected during regular post-operative follow-up visits. Functional outcomes were determined according to the Friedman and Wyman scoring system.ResultsThe proximal femoral fractures were emergency diagnoses in 11 cases and delayed diagnoses in 3 cases. The delay time was 5-6 days, with an average of 5.3 days. The mean operation time was 179.6 min (range 135-231 min) with a blood loss volume that ranged from 430 to 535 ml (average 483.6 ml). Follow-up was conducted in 13 cases between 9 and 30 months post-operation, with an average follow-up time of 17.3 months. The proximal femoral fractures were united in 12 cases at the final follow-up. One case had nonunion 13 months after the operation, underwent valgus intertrochanteric osteotomy, and healed 6 months later. The femoral shaft fractures obtained rigid union at the latest follow-up in 12 cases. One case endured nonunion 12 months after the operation. After the revision surgery and iliac bone grafting, the fracture healed 6 months later. Eight of the cases had good functional results, 4 had fair results, and results were poor in 1 case at the final follow-up.ConclusionsThe treatment of ipsilateral proximal femoral and shaft fractures with BCFS in combination with MIPPO demonstrated a high likelihood of union for both fractures and good functional results.

Dataset Information

A micro-architectural evaluation of osteoporotic human femoral heads to guide implant placement in proximal femoral fractures.

Publications

A micro-architectural evaluation of osteoporotic human femoral heads to guide implant placement in proximal femoral fractures.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets