[Effect of femoral offset on proximal femoral anti rotation intramedullary nail in the treatment of femoral trochanteric fractures].

OBJECTIVE: To investigate the effect of femoral offset (FO) on the postoperative functional results of proximal femoral nail antirotation (PFNA) in femoral trochanteric fractures. METHODS: From May 2017 to June 2019, 112 patients receiving PFNA were analyzed, X-ray and CT examination of both hips were performed before operation, and X-ray examination of both hips of pelvis was performed on the first day after operation. Among them, 71 patients showed bilateral FO difference≤ 5 mm on positive X-ray film (group A), and 41 patients showed bilateral FO difference>5 mm (group B). There was no significant difference between two groups in gender, age, operative side, course of disease, Harris score of preoperative hip joint, preoperativeFO(P>0.05). The Harris score of hip joint at 6 and 12 months was compared between two groups. The correlation between FO difference and Harris score was analyzed. RESULTS: Patients in both groups were followed up for 12 months after surgery, and all patients reached the healing criteria. The difference of Harris score of the hip joint at 6 and 12 months after surgery was statistically significant (P<0.05), and the difference of bilateral FO was negatively correlated with the Harris score of the hip joint at 6 and 12 months after surgery (R=-0.213, P<0.05), (R=-0.335, P<0.05). CONCLUSION: In the treatment of trochanteric fractures with PFNA, the greater the difference of FO between the two sides, the worse the postoperative function of the patients. The appropriate FO(the difference of FO between the two sides ≤5 mm) can improve the postoperative function of the patients.