Study on functional outcome and mechanical failure in intertrochanteric femur fracture treated with proximal femoral nail antirotation-II

Abstract
As the life expectancy has increased in recent years, the incidence of proximal femoral fractures is on rise. Common techniques for fixation of these fractures are sliding hip screw and plate or intramedullary nailing. Intramedullary nailing has advantage of short incision, less operative time, rapid rehabilitation & thus decreased medical complications. PFNA-II is newer intramedullary implant developed to obtain better fixation strength in osteoporotic bones. Prospective observational study was conducted on 49 patients. All fractures were classified by AO/OTA classification system. Patients were followed up at 4, 8, 12 and 16-weeks. Functional outcomes were assessed according to pain assessment by numeric rating scale, Parker Palmer mobility score, Harris hip score. Fracture union and mechanical failure were assessed radiologically. Mean age of the entire group was 71.84years. Male to female sex ratio was 0.81:1.00. 32.7% had A1 type, 61.2% had A2 type and 6.1% had A3 type fracture. Mean OT time was 49.29mins and mean blood loss was 117.14ml. Mean pain score at 16-weeks was significantly lower compared to that at 4, 8 and 12-weeks post-op follow-up. Distribution of mean Palmer Parker mobility score and Harris hip score at 16-weeks post-op follow-up was significantly higher compared to that at 4, 8 and 12-weeks post-op follow-up. 38.8% had excellent, 40.8% had good, 12.2% had fair and 8.2% had poor functional outcome. Helical blade back out, cut-out and medial migration was seen in one patient each. 95.9% cases had maintenance of reduction and fracture union. Mean time for fracture union was 14.26 weeks. Use of the PFNA-II to treat intertrochanteric fractures has the following advantages: quick procedure with small incision, less operative time, minimal blood loss, few complications, early weight bearing, less union time, good clinical efficacy and very few cases of complications. Good functional outcomes can be achieved, when the radiological parameters are restored. We conclude that PFNA-II is an effective treatment modality for intertrochanteric fractures, with excellent functional outcome and regaining back the pre-fall ambulatory status with minimal mechanical complications.