CEMENTLESS TOTAL HIP ARTHROPLASTY USING SPONGIOSA-I FULLY COATED CANCELLOUS METAL SURFACE: A MINIMUM TWENTY YEARS FOLLOW-UP

Background We present the results of cementless total hip arthroplasty using anatomically adapted stem and hemispherical cup with a fully coated Spongiosa metal surface, first introduced in 1982, which aims to achieve a surface structure approaching that of human cancellous bone. This implant is still being used in clinical practice with minor modifications. Aim The aim of the study is to determine the long-term outcomes of spongiosa-I metal surface hip arthroplasty over minimum of twenty years follow-up. Material and Methods Between 1983 and 1985, 209 consecutive total hip arthroplasty procedures were performed using the Spongiosa-I metal surface chrome-cobalt total hip arthroplasty. We reported clinical and radiological outcomes, frequencies and reasons of revision, influence of gender and age on the outcome and complications. Results The outcomes of 159 patients were reviewed. We lost the follow-up of 40 patients none of whom had revision surgery. The mean follow-up time was 262 months. There were 19 hips revisions, including 14 stem revisions, two cup revisions and three revisions of both components. The mean Harris hip score for patients who didn9t have revision surgery was 81.9 points. According to the criteria of Engh et al ., all implants were graded as stable bone in growth. The probability of survival of both components at twenty years, with any revision as the end point, was 97%. The probability of survival of the acetabular component was 98% and that of the stem component only was 86%. Component durability was significantly increased in the older group of patients. Conclusion The results of Spongiosa -I hip arthroplasty were excellent at a minimum of twenty years of follow-up. The outcomes of the femoral stem components were very good, while the survival rates of the acetabular component were better than any reported results in the English literature.