Abstract
Aspetic loosening is a major problem of total hip arthroplasty, especially in young and/or active patients. This study was performed to assess the clinical performance of non-cemented, metal-on-metal implant and complications including loosening and osteolysis at medium-term follow-up.
Between 1994 and 1998, 38 patients (45 hips) had a THA with a Metasul articulation. Thirty-two patients (39 hips) were available for follow up an average of 5.3 years following the operation. Patients were independently assessed by clinical examination, with use of the Harris Hip Score, patient self-assessment forms and radiographs.
The average age was 53.5 years (range 29 to 68) with a diagnosis of primary OA accounting for 34 hips and other diagnoses for 5 hips. The average Harris Hip Score for those patients without a revision was 94.7 points (range 71 to 100). One patient had a revision of a loose femoral component at 16 months, at last review he had a Harris Hip Score of 99.7 points. No patient had a loose or revised acetabular component. Two patients had an early dislocation without sequelae. Thirty-six hips were rated as very good or excellent. There was no radiological evidence of progressive radiosclerotic lines and no other evidence of loosening.
This group of young and/or active patients with Metasul articulations has clinical results equivalent to metal-on-polyethylene articulations. There is no evidence to suggest that the rate of loosening is higher as was documented by previous metal-on-metal designs. At medium term follow up there is no evidence that the metal-on-metal articulation gave rise to any new problems or complications.
The abstracts were prepared by Jean-Claude Theis. Correspondence should be addressed to him at Department of Orthopaedic Surgery, Dunedin Hospital, Private Bag 1921, Dunedin, New Zealand.
