Abstract
The rate of failure of primary THA in patients with osteonecrosis of the femoral head is higher than that in patients who undergo THA because of other diagnoses. We examined the results of cementless THA performed with second-generation in a consecutive series of young patients with osteonecrosis of the femoral head.
Sixty-five consecutive primary THAs with insertion of a femoral stem with a circumferential proximal porous coating (HG Multilock prosthesis) and a cementless acetabular component (Harris-Galante II) were performed in 52 patients with osteonecrosis of the femoral head. These patients were followed prospectively and evaluated at a minimum of 10 years after surgery. Four patients (4 hips) died and three patients (3 hips) were lost to follow-up monitoring. The remaining 45 patients (58 hips) had a mean of 11.1 years (range, 10 to 13.4 years) of clinical and radiographic follow-up.
One stem (1.7%) was revised because of aseptic loosening. Eighteen cups (31%) were revised because of excessive polyethylene wear and osteolysis. One hip (1.7%) underwent revision of both acetabular and femoral component because of excessive polyethylene wear and osteolysis. The mean Harrsi Hip Score improved from 49 points before surgery to 92.8 points after surgery in patients who did not undergo reoperation. Osteolysis around the acetabular component was present in 22 hips (37.9%). Femoral osteolysis was seen in 9 hips (15.5%), and there was no osteolysis below the lesser trochanter in any hip.
Circumferentially porous-coated second-generation femoral prostheses provide excellent fixation in young patients with osteonecrosis of the femoral head. However, a high rate of polyethylene wear and osteolysis in these high-risk patients remains a challenging problem.
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