[Treatment results and complications after PFN osteosynthesis]

Abstract

Intramedullary implants, such as the proximal femur nails (PFN), are inserted for the treatment of per-, inter- and subtrochanteric fractures. The initial experiences with these PFN, carried out by AO/ASIF in 1996, have been published.

Patients and methods: This study makes a systematic examination of the complications and clinical treatment results from 133 patients treated at our clinic from December 1997-2001 with 139 PFN in per-, inter- and subtrochanteric femur fractures. The mean age at the time of surgery was 78.4 years. All fractures were classified according to the AO system. The most frequent injuries were 31 A2.3 fractures (61.2%). All intraoperative image-converter images and all radiographs from the total period of treatment were evaluated retrospectively in accordance with 28 criteria. The degree of osteoporosis was estimated using the Singh classification.

Results: A total of 44 (31.7%) complications arose in 31 (23.3%) patients. On 11 occasions, hip screw cut-out was observed. Of these, two cases involved a Z-effect and one an inverted Z-effect. Two patients suffered a femoral neck fracture following removal of the hip screws. There were 38 (27.3%) reoperations required with 13 changes in procedure. In autumn 2002, clinical follow-up examinations were carried out on 65 (48.9%) patients who were assessed according to the Merle d'Aubigné score. A total of 51 (38.3%) patients had died at the time of follow-up. Normal ambulation was achieved by 33.8% of patients, while 64.6% were free of pain.

Conclusions: The PFN is an appropriate implant in cases of per-, inter- and subtrochanteric femur fractures. Anatomical resetting and correct implant positioning are the keys to successful osteosynthesis. The risk of implant failure is highest in the case of multi-fragmentary per- and intertrochanteric fractures in which medial strengthening has been degraded in patients aged over 80 years. The clinical results in elderly patients are unsatisfactory.