Primary Total Hip Arthroplasty Using Non-cemented Multilock Proximal Porous Coated Femoral Stem: Ten to Twelve Years Follow Up Study

Park, Sang Won; Lee, Soon Hyuck; Baek, Jong Ryoon; Chung, Jong Won; Choi, Gi Won

Abstract

PURPOSE: This study evaluated the minimum ten-year result of primary total hip arthroplasty with a non-cemented Multilock femoral stem.
MATERIALS AND METHODS
Fifty five total hip replacements in forty-four patients using a non-cemented Multilock femoral stem and Harris-Galante 2 acetabular component were performed between January 1992 and December 1994. Forty-four hips in thirty-six patients were available for follow up for an average of eleven years (range, ten to twelve years). The clinical results were evaluated based on the Harris hip scores. A detailed radiography analysis was performed by an evaluation of the radiolucent lines, femoral osteolysis, and fixation stability by Engh Method.
RESULTS
The average Harris hip score improved from 54.3 points preoperatively to 93.6 points postoperatively. Non-progressive radiolucencies < 2 mm in width were observed in nine (20.5%), and femoral osteolysis was observed in thirteen cases (29.5%). For the fixation stability, osseous ingrowth was noted in thirty nine cases (88.6%) and fibrous ingrowth was observed in two (4.5%). There were three (6.8%) cases with unstable fixation. Two hips underwent revision. The survival rate of the femoral component was 93.2% (forty one cases) after a minimum ten-year follow up.
CONCLUSION
The non-cemented Multilock femoral component provided excellent clinical and radiographic results. However, the rate of femoral osteolysis was relatively high (mostly restricted to zone 1 and 7).