Liu B, et al. - Via this retrospective study including 1633 hips, researchers examined the incidence, classification and risk factors for intraoperative periprosthetic femoral fractures with collum femoris preserving (CFP) stem, a special-designed femoral neck preserving component. Periprosthetic femoral fractures were reported in 3.2% of patients undergoing total hip arthroplasty with a CFP stem. Twenty four patients (45.3%) had Vancouver type A fractures, 27 patients (50.9%) had Vancouver type B fractures and 2 patients (3.8%) had Vancouver type C fractures. Risk (protective) factors that were independently associated were surgical history, neck-shaft angle, neck length preserved, canal flare index and bone mineral density. Patients with CFP stems had cracks of the femoral neck and fractures on the front side of the proximal femur more commonly.