Background: Periprosthetic fractures of the femur after primary total hip arthroplasty (THA) can be complex and difficult injuries to treat. Because of the increased prevalence of THA, an overall increase is anticipated in the incidence of this complication. Vancouver types B1 and B2 periprosthetic femur fractures (defined as fractures around or just below the stem, with well-fixed and loose femoral stems, respectively) are particularly challenging to accurately classify and thereby treat owing to the difficulty in interpreting stability of stems on initial radiographs. To determine whether the method of stem fixation (ie, cement or press fit) may be a predictor of types B1 and B2 fractures, we performed a PubMed search and independently assessed data from 11 studies with 293 patients.
Methods: Studies were included that provided individual patient data (ie, fracture type, method of stem fixation, and stability of stem at the time of revision procedure). Only patients with Vancouver types B1 and B2 fractures were included. Statistical analysis was performed using a random-effects model, estimated with a restricted maximum likelihood method.
Results: A total of 59 and 92 cemented stems were found to be loose and well fixed, respectively (39% and 61%, respectively; n = 151). A total of 17 and 63 uncemented stems were loose and well fixed, respectively (22% and 78%, respectively; n = 80). The overall estimate of the odds ratio was 0.96 (95% confidence interval, 0.86–1.06).
Conclusions: Our findings suggest that fixation method of stems cannot significantly predict the likelihood of having Vancouver types B1 and B2 fracture patterns.
Bennett, David M.; Logan R. Koehler; David J. Margolis; Matthew J. Radelet; Zhenqiang Lu; Tony G. Pedri; Michael M. Decker; and Michael D. Miller. "Predicting Vancouver Types B1 and B2 Periprosthetic Fractures of the Femur." UNM Orthopaedic Research Journal 5, 1 (2016). https://digitalrepository.unm.edu/unm_jor/vol5/iss1/20