[Complications of internal fixation by a short proximal femoral nail].

PURPOSE OF THE STUDY

The article presents analysis of complications of the treatment of unstable fractures of the proximal femur by the proximal femoral nail (PFN Synthes).

MATERIAL

Between October 1997 and October 2003, 239 patients were treated for unstable fractures of the proximal femur, 89 men and 150 women, average age 71 years. The minimum follow-up was 12 months. Unstable was considered a fracture in which it was impossible to restore by reduction the medial support -- the Adams' arch, i. e. the region below the lesser trochanter in subtrochanteric fractures. Prevailing in the group of patients were unstable pertrochanteric fractures (AO 31 A2.1, A2.2) that occurred in 55 % of patients, per-subtrochanteric fractures (AO 31 A2.3) accounted only for 26 % and subtrochanteric fractures (AO 31 A3.3) for 19 %.

RESULTS

The fracture healed in 95 % of patients within 6 months and in 98 % of patients within 9 months. There were 29 intraoperative complications recorded in 19 patients (12 %). This category included also intraoperative technical difficulties. Only 9 patients (4 %) were reoperated on. Early postoperative complications occurred in 16 patients (8 %) requiring reoperation in 7 cases. Six late postoperative complications occurred in 3 patients.

DISCUSSION

Intramedullary implants for internal fixation of the proximal femur tolerate higher static and several times higher cyclical loading as compared to DHS types of implant. As a result the fracture heals even without the primary restoration of the medial support. The implant temporarily compensates the function of the medial column. When this function is not restored in a limited period of time, the internal fixation, although correctly performed, fails. The main cause of complications are technical mistakes or failure to observe the proper surgical technique.

CONCLUSION

The most frequent mistake is reduction with the persisting varus position or distraction in the fracture line, incorrect placement of the screw in the femoral neck or the nail in the femoral shaft, wrong choice of the length of the screws, unnecessary hesitation in solving the defect in the course of the treatment. Forced insertion of the implant may cause additional damages to the skeleton. PFN is a quality implant for the treatment of unstable pertrochanteric and subtrochanteric fractures of the femur. The number and severity of complications may be reduced by the observance of proper principles of reduction and exact surgical technique.