Size of the femoral head and acetabular revision in total hip-replacement arthroplasty

Fifty-nine revisions that were done for aseptic acetabular loosening after 6,128 total hip arthroplasties for degenerative arthritis or traumatic arthritis were studied. These revisions were in forty-four (approximately 1 per cent) of 4,576 hips that had a twenty-two-millimeter femoral-head component, in two of 520 that had a twenty-eight-millimeter femoral-head component, and in thirteen (approximately 2.5 per cent) of 487 that had a thirty-two-millimeter femoral component was associated with the highest rate of acetabular revision (p < 0.001). The dimensions of the acetabular wall were thinner in the hips that had the thirty-two-millimeter component than in those that had the twenty-two-millimeter component (p < 0.05). Multivariate analysis demonstrated a significantly increased risk of acetabular loosening in men and in patients who were less than sixty years old.