Objectives. One commonly used rat fracture model for bone and mineral research is a closed mid-shaft femur fracture as described by Bonnarens in 1984. Initially, this model was believed to create very reproducible fractures. However, there have been frequent reports of comminution and varying rates of complication. Given the importance of precise anticipation of those characteristics in laboratory research, we aimed to precisely estimate the rate of comminution, its importance and its effect on the amount of soft callus created. Furthermore, we aimed to precisely report the rate of complications such as death and infection. Methods. We tested a rat model of femoral fracture on 84 rats based on Bonnarens’ original description. We used a proximal approach with trochanterotomy to insert the pin, a drop tower to create the fracture and a high-resolution fluoroscopic imager to detect the comminution. We weighed the soft callus on day seven and compared the soft callus parameters with the comminution status. Results. The mean operating time was 34.8 minutes (. sd. 9.8). The fracture was usable (transverse, mid-shaft, without significant comminution and with displacement < 1 mm) in 74 animals (88%). Of these 74 usable fractures, slight comminution was detected in 47 (63%). In 50 animals who underwent callus manipulation, slight comminution (n = 32) was statistically correlated to the amount of early callus created (r = 0.35, p = 0.015). Two complications occurred: one death and one deep infection. Conclusions. We propose an accurate description of comminution and complications in order to improve experiments on rat femur fracture model in the field of laboratory research. Cite this article: Bone Joint Res 2013;2:149–54

Objectives

Bisphosphonates are widely used as first-line treatment for primary and secondary prevention of fragility fractures. Whilst they have proved effective in this role, there is growing concern over their long-term use, with much evidence linking bisphosphonate-related suppression of bone remodelling to an increased risk of atypical subtrochanteric fractures of the femur (AFFs). The objective of this article is to review this evidence, while presenting the current available strategies for the management of AFFs.

Objectives

The use of two implants to manage concomitant ipsilateral femoral shaft and proximal femoral fractures has been indicated, but no studies address the relationship of dynamic hip screw (DHS) side plate screws and the intramedullary nail where failure might occur after union. This study compares different implant configurations in order to investigate bridging the gap between the distal DHS and tip of the intramedullary nail.

Objectives

Because of the contradictory body of evidence related to the potential benefits of helical blades in trochanteric fracture fixation, we studied the effect of bone compaction resulting from the insertion of a proximal femoral nail anti-rotation (PFNA).

Introduction

The objective of this study was to determine if a synthetic bone substitute would provide results similar to bone from osteoporotic femoral heads during in vitro testing with orthopaedic implants. If the synthetic material could produce results similar to those of the osteoporotic bone, it could reduce or eliminate the need for testing of implants on bone.