Technique of Biologic Fixation of Subtrochanteric Femoral Fractures with Dynamic Condylar Screw (DCS)

Abstract

Objective Treatment of closed comminuted subtrochanteric fractures using the dynamic condylar screw (DCS), with the goal of reducing operating time, blood loss, and incidence of delayed union. Indications Comminuted subtrochanteric fractures, especially types B and C of the AO classification. Fracture line extending to piriformis fossa precluding use of an intramedullary device. Poor general condition, i. e., unable to withstand prolonged anesthesia as required in open reduction and internal fixation (ORIF)/nailing. Contraindications Compound fractures. Obesity. Calcar comminution is not a contraindication. Surgical Technique Approach either through small proximal and distal incisions or limited exposure of the fracture site without opening the region of comminution and preservation of medial fracture hematoma. DCS inserted under image intensifier control. Plate slid beneath vastus lateralis. Rotated 180° to allow barrel to slide over condylar screw. Alignment in all three planes confirmed under radiologic control. Proximal and distal screws inserted to stabilize the fracture. Results Between 10/1995 and 02/1999, 28 men and three women with subtrochanteric fractures were treated with a DCS using biologic principles. Union was achieved in all 31 patients (100%) and full weight bearing possible after an average of 4.9 months. The average operating time was 2 h, and blood loss averaged 430 ml. Only one patient had a superficial infection, which settled on local debridement and antibiotics. Malunion was seen twice (6.4%) which did not require further surgery. These results are superior to open technique in respect to blood loss, surgical time, and union rate.