Femoral revision hip arthroplasty with uncemented, porous-coated stems

One hundred seventy-five cementless femoral hip revision surgeries with extensively porous-coated stems and 161 concomitant acetabular revisions done from 1984 to 1991 were retrospectively reviewed. Average age at surgery was 62.4 years. Followup ranged from 2 to 10 years (average, 5 years). One hundred sixty-eight femoral components (96%) remain in place. Two unstable components, 1 stable fibrous component, and 1 bone ingrowth component were painful and required rerevision. Two femoral components were removed as part of resection arthroplasties for repetitive acetabular failure caused by pelvic dissociation. One component was removed for late hematogenous infection. Using the Engh radiographic criteria, femoral stems were judged to have achieved bony ingrowth in 82.8% (n = 174) of the cases. Bony ingrowth occurred more frequently when the canal was filled with the prosthesis and with lesser degrees of bone stock deficiency. Severe stress shielding occurred in 11 (7.6%; n = 144) of the bone in-grown cases and correlated with preoperative osteoporosis and larger diameter prosthesis. Significant thigh pain was less common in the bone ingrown (4.2%; n = 144) than in the stable fibrous group (18.5%; n = 27). Significant thigh pain in bone ingrown stems was more likely to occur with osteoporotic and bone stock-deficient femurs. To date, significant wear and osteolysis have not been observed.