Medicine: All-Metal Hip

All-Metal Hip When Air Force Veterinarian Harry A. Gorman was working for a master’s degree at Ohio State University, he designed an all-metal device to replace the hip joint in injured dogs. One of the judges who passed on Colonel Gorman’s work was Orthopedic Surgeon Judson Wilson. The artificial joint looked so good and worked so well in dogs that Dr. Wilson decided to try minor design changes that would make it suitable for human patients.

Last week, in Columbus’ University Hospital, Gene Snyder, 25, a victim of rheumatoid arthritis, who already had a partial artificial joint (made of steel) in his right hip, was laid out on his right side and anesthetized. Surgeon Wilson made a long incision clear down to the bone, and exposed the left hip joint which had been fused by the arthritic inflammation. He sawed off the top of the thigh bone (femur), ground the remaining end of the bone to the right depth and angle. He reamed out a hemispheric cavity in the pelvic bone, to accommodate the socket part of the metal ball-and-socket joint. Dr. Wilson drove a long shaft (bearing the ball) into the marrow cavity and fitted a flange (just below the ball) to the head of the femur. Another flange, on the socket, he screwed to the rim of the acetabulum (the socket cavity in the pelvic bone). A collar to hold the ball in the socket completed the device (see diagram). Patient Snyder will be walking in three weeks.

Dr. Wilson will perform two more such operations, then wait six months to observe results before recommending wide adoption of the Gorman joint. But he has high hopes for it. Moving parts are metal against metal, lubricated by body fluids, so no foreign material is in moving contact with human tissue (which has caused trouble in some earlier plastic and metal restorations). Made of Stellite (a chromium-cobalt alloy), the joint should outlast the life of the recipient, with no corrosion.