Abstract
Introduction: The aim of this study was to study the intermediate term (5-10 year) results of the ‘Metasul’ type of metal-on-metal hip arthroplasty.
Method: A prospective analysis was performed of the clinical and radiological findings of the patients who underwent the ‘Metasul’ hip arthroplasty by the senior author (Mr. Benke). The clinical evaluation was performed with the Charnley’s modification of the Merle d’ Aubigne scoring system as well as the Oxford Hip Scoring Sheet. All the patients operated from February 1995 till July 2000, were included in the study. Of the total of 99 patients, 5 patients died prior to the final review and 4 were lost to follow-up. The final study group hence contained 90 Hip Arthroplasties in 77 patients.
Results: The results were analysed using the Charnley categories, and as expected the patients of Category ‘A’ achieved the best final results with the d’Aubigne score rising from 8.6 to 17.2 and Oxford scores of 5.7/60. The patients of Category ‘B’ had good results (Final Oxford score of 7.3/60, and d’Aubigne score of 16.9). The Category ‘C’ patients had moderate results with the d’Aubigne score of 15.1 and Oxford score of 17.7/60. Three patients needed revision hip arthroplasty for the following reasons: aseptic acetabular loosening (1), infection (1) and massive osteolysis (1).
Discussion: The clinical results obtained with the use of the ‘Metasul’ articulation are comparable to those obtained by the metal-on-polyethylene articulation. The clinical success, the retrieval data of low wear from laboratory studies and the historical data of 40 years with an absence of clinical consequences of elevated serum Co ion levels, encourages the use of this alternate bearing surface.
Correspondence should be addressed to Mr Bimal Singh, BOSA at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE
