Long-term comparison of porous and hydroxyapatite sleeves in femoral revision using the S-ROM modular stem.

We prospectively evaluated the results of a single-surgeon series of 28 femoral revision arthroplasties using the S-ROM modular stem with either a porous-coated sleeve (15 hips) or a hydroxyapatite-coated sleeve (13 hips) after a mean of 10 years (range, 8-14 years). Three femoral stems underwent repeat femoral revision for aseptic loosening in association with Paprosky type III bone defects after a mean of 9 years in vivo (range, 8-10 years). One on these 3 had a porous-coated sleeve and the other 2 had a hydroxyapatite-coated sleeve. With repeat revision for any reason as the end point, femoral component survival was 83.8% at 10 years for the entire series, and 93.3% for the porous-coated sleeve group and 76.2% for the hydroxyapatite-coated sleeve group, respectively (log-rank test, P=0.588). No significant difference was detected between the 2 groups regarding postoperative Harris hip scores, bone ingrowth, stress-shielding, osteolysis, or complication rates. At a mean of 10 years postoperatively, hydroxyapatite-coated sleeves offered no clinical benefit over porous-coated sleeves for revision hip replacement using the S-ROM modular stem. Our findings also indicate that hydroxyapatite-coated sleeves did not reduce late mechanical stem failures in cases with a deficient femur.