Effect of Preoperative Bisphosphonate Treatment on Fracture Healing after Internal Fixation Treatment of Intertrochanteric Femoral Fractures

PURPOSE: There are concerns that administration of bisphosphonate (BP) can substantially suppress bone turnover, potentially interfering with fracture healing. We investigated the effects of preoperative BP administration before internal fixation of intertrochanteric femoral fractures using fracture healing and clinical outcomes. MATERIALS AND METHODS: We retrospectively analyzed data from 130 patients who underwent internal fixation for osteoporotic intertrochanteric femoral fractures between March 2012 and July 2016. Patients previously treated with BPs for at least 3 months (BP group; n=29) were compared with the remaining patients (BP-naïve group; n=101). Radiographs were used to assess and compare fracture healing 3 months and 1 year postsurgery. The primary clinical outcome measure assessed was change in Koval score. RESULTS: Fracture union at 3 months after surgery was verified in 72.4% of patients (21/29) in the BP group and 90.1% of patients (91/101) in the BP-naïve group (P=0.027). Fracture union at 1 year postsurgery (BP group, 93.1% [27/29] vs. BP-naïve group, 97.0% [98/101], P=0.310) and change in Koval score (1.1 vs. 1.0, P=0.694) were not significantly different between the groups. Multivariable logistic regression analysis revealed that a history of BP administration was associated with an increased risk of delayed union at 3 months postsurgery (P=0.014). CONCLUSION: Preoperative administration of BP was associated with a decreased fracture healing rate 3 months after internal fixation, compared with BP-naïve patients. Therefore, patients previously treated with a BP should be carefully allowed to wean off walking aids and transition to full weight-bearing in the early postoperative period.