Comparison of hydroxyapatite-coated and non-hydroxyapatite-coated noncemented total hip arthroplasty in same patients.

The comparison between standard blasted and hydroxyapatite (HA)-coated cementless femoral stems (CLS stem) was made in the same patients who have bilateral late-stage osteonecrosis. Clinical and radiographic evaluations were performed in 20 patients (among 29 patients) with the minimum follow-up of 10 years (range, 123-168 months). Endosteal bone formation was found in all patients of both stems, and no radiolucent line was observed. The mean of initial stem subsidence was 1.27 +/- 0.95 mm with the standard stem and 0.59 +/- 0.56 mm with the HA-coated stem. Other results, such as hip score, endosteal bone formation, cortical hypertrophy, osteolysis, and heterotopic ossification showed no statistical differences. These have suggested that the fixation obtained by the cementless stem with a corundum-blasted surface is stable enough to get excellent clinical and radiographic results without the HA coating.