Results of the Anatomic Medullary Locking Total Hip Arthroplasty at a Minimum of Twenty Years

Abstract

Between October 1982 and December 1984, the senior author performed 223 total hip arthroplasties in 215 patients with use of the anatomic medullary locking hip stem and TriSpike cup. We now report on 119 of these hips at a mean of 22.0 years (range, 20.0 to 25.0 years) after surgery. Of the fifty-six hips with minimum twenty-year follow-up radiographs and the original acetabular component, seventeen (30.4%) had pelvic osteolytic lesions measuring larger than 1.5 cm(2). Of the sixty-eight hips with twenty-year radiographs and the original anatomic medullary locking stem, twenty-five (36.8%) had femoral osteolytic lesions measuring larger than 1.5 cm(2). Acetabular osteolysis was significantly associated with cup loosening (p = 0.006), but the presence of femoral osteolysis was not associated with stem loosening. Kaplan-Meier analysis, with revision for any reason as the end point, revealed that the survival rate at twenty years was 85.8% +/- 5.2% for the acetabular shell and 97.8% +/- 2.2% for the stem. The most common reoperation was polyethylene exchange because of wear or osteolysis.