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

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).

Cementless Total Hip Arthroplasty with Circumferentially Proximal Porous-Coated Femoral Stem -Minimum 10-Year Follow-up Results

Purpose: The results of a more than 10-year follow-up after total hip arthroplasties with circumferential and proximal porous-coated femoral stems were evaluated. Materials and Methods: Seventy-six patients (80 hips), who were operated on between Aug. 1991 and July 1994, were followed for more than 10 years after primary total hip arthroplasties using Multilock stems. The mean age at the time of the operations was 47.3 years old and the mean duration of follow-up was 12.3 years. The clinical results and radiological findings were evaluated. Results: The mean Harris hip scores improved from 54.7 points to 88.5 points at the time of the 10-year follow up. On the last follow-up radiograph, endosteal bone formation was observed in 70 hips (90%) and all femoral stems were biologically stable. Femoral osteolysis, which was linear in Gruen zone I and VII and mostly restricted to the proximal zones, was observed in 67 hips (84%), and no hip had distal osteolysis in the femur. There was no loosening, migration, or revisions of the stems. Conclusion: Total hip arthroplasties using circumferential and proximal porous coated Multilock femoral stems demonstrated stable osseous fixation and no distal osteolysis for a minimum 10-year follow-up; therefore, all stems were reported to have satisfactory outcomes. With improvement of cup design and liner wear, circumferential and proximal porous coating designs of femoral stems can be an alternative answer to mechanical failure due to aseptic loosening.

Cementless Total Hip Arthroplasty Using Circumferentially Porous Coated Femoral Stem: Minimum Five-Year Followup Study / 대한정형외과학회잡지

PURPOSE: The result of more than 5 year follow up after cementless total hip arthroplasty using circumferentially porous coated femoralstem was evaluated. MATERIALS AND METHODS: Eighty five patients (95 hips) were followed more than 5 years after a primary total hip arthroplasty using multilockfemoral stem, which was circumferentially porous coated at the proximal 1/3 of femoral stem. The average age at the time of operation was 48 years. The average duration of followup was 6.9 years. The Harris hip score was used for the evaluation of clinical results. The canal fit of the stem at the proximal canal and isthmus level was evaluated from the postoperative radiographs. The component stability, endosteal bone formation, radiolucent line, osteolysis and polyethylene wear were evaluated from serial followup radiographs. RESULTS: The mean Harris hip scores increased from 60.1 points preoperatively to 91.3 points at the time of the most recent followup. All hips had a press fit at both the proximal canal and isthmus level. On the lastest followup radiograph, endosteal bone formation was observed in all cases (100%). The radiolucent line around the femoral stem was observed in 92 cases (97%), mainly Gruen zones II, III, IV, V and VI. The radiolucent line was thinner than 1 mm and there was no progressive widening. The acetabular osteolysis developed in 31 cases(33%) and the femoral osteolysis in 31 cases (33%) mostly in Gruen zones I, II, and VII. There was no distal osteolysis in the femur. There was no loosening or migration of cup and stem. The mean linear wear was 1.29 (0-5.69) mm and the mean rate of linear wear was 0.18(0-0.81) mm/year. Seventeen hips (18%) were revised for the dissociation of polyethylene liner in 10 hips (11%), excessive wear in the polyethylene liner and progressive osteolysis in 6 hips (6%) and recurence of tuberculous arthritis in 1 hip (1%). CONCLUSION: Cementless total hip arthroplsty using circumferentially porous coated femoral stem showed good medium-term results clinicallyand radiologically, it is likely that circumferential porous coating in the femoral stem induces bone ingrowth and prevents distal osteolysis.