DHS osteosynthesis for stable pertrochanteric femur fractures with a two-hole side plate

The sliding hip screw is the implant of choice for the operative treatment of stable pertrochanteric femur fractures (AO classification 31-A.1). For this indication, a four-hole side plate with four bicortical screws is widely used to allow full weight bearing immediately after operation, but scientific support for the need of such a long side plate is not available. A shorter side plate is potentially less invasive. Therefore, we retrospectively evaluated all 148 consecutive patients (median age 80 years) with a stable pertrochanteric femur fracture who were treated between 1995 and 2001 with a dynamic hip screw (DHS) and a short (two-hole) side plate and immediate full weight bearing mobilisation. Although two wound hematomas and four wound infections occured, 145 fractures healed radiologically without implant-related complications within 6 months. Two hip screws cut out of the femoral head due to a poor position. In one patient, the side plate broke out after a fall out of bed on the fifth postoperative day. Pull off of any two-hole side plate during early full weight bearing mobilisation without further trauma was not observed. We conclude that fixation of stable pertrochanteric femur fractures with a two-hole DHS is safe. The traditional use of a four-hole DHS plate for this indication is therefore 'over-treatment' since it is more invasive.