Dynamic hip screw in the management of reverse obliquity intertrochanteric neck of femur fractures

Aim: To assess the results of treatment of reverse obliquity intertrochanteric fractures at Middlemore hospital and to compare this to the results in the literature. Method: This was a retrospective review of X-rays and clinical notes followed by phone conversations with the patients. Results: Forty-two patients with reverse obliquity intertrochanteric neck of femur fractures were included. They were treated with one of three different implants (dynamic hip screw (DHS), reconstruction nail (RCN) or proximal femoral nail (PFN)). The revision rate for the DHS was 11% (4/35), RCN 40% (2/5) and PFN 0% (0/2). Of the 35 DHS implants, one was below a hip fusion. Of the remaining 34, 25 had the screws placed within 25 mm of the subchondral bone at the centre of the femoral head and nine did not. None of the implants placed within 25 mm of the femoral head failed while three of the others did. Conclusion: The results for treating this type of fracture with the DHS in this series are significantly better than that documented in the literature for the same fracture type, the reasons for this are unclear. There seems to be a trend towards better results with more accurate placement of the lag screw with this device. In this series, the RCN was less successful than the DHS and the PFN was used too infrequently to draw useful conclusions about its effectiveness.