Although 50 years have passed since Charnley started performing total hip arthroplasties, there are relatively few patient studies with a follow-up period of over 30 years. We studied radiograms of patients who had undergone Charnley total hip arthroplasty between 1975 and 1981 and evaluated the results at 26-35 years (mean 30.5 years) after the operation.
The operations were performed in 87 joints of 82 patients (26 males and 56 females) aged 26-81 years (mean age 56 years) at the time of surgery. A monoblock-type Charnley stem with a 22-mm head was used in all patients. The stem had a matte satin surface finish and a flange or round-back shoulder. The socket was made of ultra-high-density polyethylene without a flange. All operations were performed by one surgeon using the original Charnley method in all patients, excluding the first five.
Thirty years after the operation, 48 patients have died, 5 had an infection, 9 were lost to follow-up, and 20 patients with 24 joints are still alive. In 77 patients (82 joints), after excluding the 5 with infection, the socket and stem survival rates were 54 and 75% at 30 years after the operation when radiographic loosening or revision surgery was defined as the end point. With revision surgery as the end point, the rates were 68 and 82%, respectively.
These results were as favorable as those with surgical techniques (including the first-generation cement technique) and implants in the early period. Although new techniques and implants have since been introduced, their long-term results should exceed those in this study. The results of this study should provide a valuable index with which to compare the long-term studies of current total hip arthroplasty.