Treatment of distal femur fractures with less invasive stabilization system

Abstract

Objective To explore the operative techniques in treatment of distal femur fractures with less invasive stabilization system (LISS). Methods From July 2003 to February 2007, 53 patients with fresh distal femur fractures were treated with LISS. There were 37 males and 16 females, an average age of 45.8 years (ranged from 19 to 82 years). There were two patients with type 33A1 fractures, 11 with type 33A2 fractures, 10 with type 33A3 fractures, three with type 33C1 fractures, 15 with type 33C2 fractures and 12 with type 33C3 fractures according to AO classification. After the articular segments of the fracture were treated with open reduction and fixation, fractures in the metaphyseal area were reduced indirectly. Then, the LISS plate was inserted through a small incision of the knee between the lateral vastus muscle and the periosteum. About 4-6 screws were inserted through stab incisions and locked into the plate holes. Results All patients were followed up for average 25.9 months. The X-ray showed fracture healing at mean 14.2 weeks ( ranged from 8 to 16 weeks) after operation, without fixation failure, implant breakage or deep infection. The mean range of motion ( ROM ) of the knee was 1°- 15°. According to the modified Hospital for Special Surgery (HSS) knee score, 33 patients were rated as excellent, 17 good and i fair, with HSS score of 67-99 (average 87.6). Conclusions The application of long plates fixed with individual screws is advantageous. The plate should be internally rotated by 10° to match the slope of the lateral femoral condyle. Palpation through a small incision over the proximal end of the plate is helpful to confirm the correct placement of the plate on the exact lateral aspect of the femur. Lateral and anteropesterior radiographs of the affected femur should be done before insertion of screws into femoral shaft. As for osteoporotic or comminuted fractures, bicortical locking screws should be used in the shaft area. Key words: Femoral fractures; Fracture fixation; internal; Less invasive stabilization system