Several authors have reported complications from screw removal after treatment of slipped upper femoral epiphysis by single screw fixation, and have attributed these to poor screw design. We have developed a simple and reliable method of screw removal which uses a cannulated 8.0 mm end-threaded cancellous screw (Smith & Nephew Richards Medical, Memphis, Tennessee) and a specially designed cannulated trephine. The method has been successful, with minimal complications, and a limited surgical exposure