Hydroxyapatite-coated total hip replacements in patients 65 years of age and over.

Prospective review examined 69 patients aged over 65 years (mean: 73 years; range: 65 to 85 years) who underwent 72 primary hydroxyapatite-coated total hip replacements by one surgeon. The femoral component used was titanium alloy coated by hydroxyapatite on the proximal third and the acetabular component was spherical and unthreaded, coated with hydroxyapatite. All patients were evaluated clinically by Harris Hip Score and radiologically using Engh's criteria with a mean follow-up of 86 months (range: 29 months to 10 years). Preoperative radiologic evaluation for osteoporotic bone using the Singh index was performed. Average Harris Hip Score increased from 45 before surgery to 89 at last follow-up. Two femoral and one-acetabular components were shown to probably be loose, but none was definitely loose or unstable by Engh's criteria. There was no correlation between clinical and radiologic results with respect to age, sex, and preoperative diagnosis. In contrast, significant statistical correlation was demonstrated between Charnley groups A or B, and group C, with regard to the Harris Hip Score (p = 0.047). There was no correlation between Charnley groups and radiological results. There was no statistical difference between patients with osteoporotic bone (Singh 1-3) and non-osteoporotic bone (Singh 4-6) with respect to clinical and radiologic evaluation. These early clinical and radiologic results compare favorably with those of hydroxyapatite-coated total hip replacements for younger patients and cemented total hip replacements in older patients. We recommended that hydroxyapatite-coated total hip replacements should not be reserved for younger patients. They can be used safely in patients over 65 years of age, promising minimal postoperative thigh pain and satisfactory clinical and radiologic results.