Does the Proximal Femur Geometry Predict Early Functional Outcome after Plate Fixation of Geriatric Pertrochanteric Fractures?

BACKGROUND: The proximal femur geometry determines the hip force distribution. The femoral neck axis length (FNAL), the hip axis length (HAL), the femoral head diameter, and the femoral neck-shaft angle (FNSA) could influence the risk and outcome of pertrochanteric fractures. Restoring these parameters to their prefracture values could predict early hip function.

AIM: To determine if the postoperative proximal femur geometry of geriatric patients with plating for pertrochanteric fractures predicts the early functional outcome.

MATERIALS AND METHODS: The study was a prospective study carried out at the National Orthopaedic Hospital Enugu for 18 months. Geriatric patients who had Proximal Femoral Locking fixation for pertrochanteric fractures were recruited. Radiological parameters of the proximal femur in the unaffected and fixed hips were measured and compared. The functional outcomes of the patients were measured at 3 months postoperative period using the Harris hip score (HHS). Multiple linear regression was conducted on the parameters to determine the HHS.

RESULTS: Thirty patients participated in the study, with a significant difference (P < 0.001) in the mean FNSA between unaffected (M = 128.69, standard deviation (SD) =2.93) and operated hips (M = 121.81, SD = 8.86). The FNSA was the only significant predictor of hip function, with a 1-degree increase improving the HHS by 1.30.

CONCLUSION: There is a significant difference in the FNSA between the unaffected and the operated hips. The FNSA significantly predicts the early hip function and should be reconstructed to within normal range during surgery.