Minimum 10-Year-Results of Extensively Porous-Coated Stems in Revision Hip Arthroplasty

Abstract
Obtaining predictable, stable fixation of revision femoral implants is important for the long-term success of revision hip arthroplasty. The authors report on minimum 10 years clinical and radiographic followup of 170 patients with extensively coated cementless revision femoral components. With a range of followup of 10 to 16 years and a mean of 13.2 years, a survivorship of greater than 95% was reported. Clinically, the average Postel-D'Aubigne pain and walking score improved from a preoperative score of 5.4 points to 10.8 points postoperatively. Eighty-two percent of the hips had radiographic evidence of a bone-ingrown prosthesis and 13.9% had evidence of stable fibrous fixation. Four percent of stems were unstable as seen on radiographs. Six stems were revised to larger extensively coated stems and one stem is causing pain and is unstable but has yet to be revised. The overall mechanical failure rate was 4.1%. Stress shielding was greatest in patients with stems larger than 16.5 mm and in osteoporotic bone (Dorr Type C). Nine percent of patients had significant thigh pain including all of the patients with unstable stems. In the presence of bone loss in the proximal metaphyseal region of the femur, fixation of the femoral component is predictable when optimizing prosthetic-bone fit in the diaphyseal region of the femur using an extensively coated femoral component.