THE ALIGNMENT OF HIP JOINT SOCKETS IN HIP JOINT REPLACEMENT

摘要

An apparatus for aligning an acetabular cup for proper placement in a socket 54 in hip joint replacement includes a frame having feet 61, 62 which are placed against and fastened to the anterior superior iliac spines 52 and the pubic tubercles 53 respectively of the pelvis. A light beam is directed from a source 75 through an aperture 80 to a mirror 91 mounted on an implant inserter by means of arm 92. The light beam is reflected back from the mirror 91 to a target region 84 defined on face plate 74. When the incident and reflected beams are coincident, the cup is aligned for correct placement. The face plate 74 is rotatably (71) and pivotably (79) mounted for precise adjustment of the angles of abduction and anteversion respectively.