RESUMEN
Surgical intervention is the first choice treatment for intertrochanteric fractures that are common in clinical practice. Cephalomedullary nailing with two parts inserted respectively into the femoral medullary cavity and femoral head has been the mainstream protocols for the elderly patients with intertrochanteric fracture, but insertion of the cephalomedullary nail may likely lead to the outward displacement of the femoral shaft and the inversion and rotation of the head and neck bone mass, namely the so-called wedge effect. However, few reports have dealt with how to prevent the wedge effect and reduce the complications it may cause such as coxa vara deformity. The present review expounds and analyzes the concept, biomechanical mechanism, influencing factors, measurements, and prevention methods of the wedge effect, hoping to help the surgeons who try to avoid the wedge effect in surgical treatment.