Rate of contralateral hip fracture after dynamic hip screw vs intramedullary nail for treatment of pertrochanteric hip fractures.

A retrospective, comparative study was performed reviewing the electronic medical records and digital radiographs of patients who underwent treatment for intertrochanteric and pertrochanteric hip fractures with either a hip screw and side plate (HSSP) or intramedullary nail. A total of 430 patients were treated with HSSP, and 725 were managed with a cephalomedullary nail (CMN). Of these, 103 sustained a contralateral hip fracture. Fixation technique was not associated with a significant difference in the rate of contralateral fracture. Among the patients with a contralateral fracture, the median time to contralateral fracture was 119.28 months following HSSP and 81.97 months following CMN. Bisphosphonate use was found to be a significant predictor of contralateral fracture for all patients, but when matching using propensity scores, its use was found to be insignificant. In conclusion, there was no difference in the rate of subsequent contralateral hip fracture when comparing HSSP with CMN. Additionally, the time to second surgery between the two treatment modalities was found to be statistically insignificant. It is unclear if bisphosphonate use increased the odds of having a contralateral fracture, regardless of the surgical intervention. The difference in the bisphosphonate effect using propensity score matching suggests that the results may be due to confounding variables and bias.