Reverse oblique intertrochanteric femoral fractures treated with the Intramedullary Hip Screw (IMHS)

Aims: Reverse oblique intertrochanteric fractures (OTA/ AO 31-A3) have unique biomechanical properties that confer difficulties in obtaining stable fixation with the conventional sliding dynamic condylar screw. Recent studies have recommended the use of cephalocondylic intramedullary devices for these unstable fractures. Both the Proximal Femoral Nail (PFN) and the Gamma Nail (GN) have shown good outcome results but the results of treatment with the IMHS have not been reported in the literature. Methods: Between 1999–2008 6724 consecutive hip fractures were treated at our institute. There were 2586 extracapsular fractures and 307 subtrochanteric fractures. 115 of the extracapsular fractures had a reverse oblique pattern and 63 of these were treated with the IMHS. We retrospectively reviewed clinical and radiological records for the reverse oblique intertrochanteric fractures treated with the IMHS. Follow-up duration ranged from 8 months to 6 years. Results: Among the 63 patients treated with the IMHS, 56 (88%) fractures were reduced satisfactorily with only one poorly positioned hip screw in the femoral head. There were no cases of femoral shaft fracture, screw cut-out or collapse at the fracture site. The orthopaedic complications were two cases of mal-rotation, two cases of non-union, two cases of distal locking bolts backing out, and one cracked nail. 30 day mortality was 6.5%. Conclusion: Cephalo-medullary nailing devices have been recommended for the treatment of reverse oblique intertrochanteric femoral fractures. Our clinical and radiological outcomes with the IMHS compare favourably to the results in reports where other cephalo-medullary devices have been used. Therefore we consider the IMHS a good option for the treatment of these unstable fractures.