FIFTEEN TO TWENTY YEAR FOLLOW-UP RESULTS OF HIP ARTHROPLASTY USING CLS (CEMENTLESS SPOTORNO) FEMORAL STEM

Abstract

Purpose: The purpose of this study is to evaluate the clinical and radiological results of the total hip arthroplasty using the CLS stem, of which we were able to follow up for 15~20 years after operations.

Materials and Methods: Among 104 patients who underwent the total hip arthroplasty using the CLS stem from 1988 to August 1993, we evaluated the clinical and radiological results of 65 hips of 51 patients, which were able to be followed up for more than 15 years. The average age at the operation was 45 years old (22~62 years old) and the average follow-up duration was 17 years and 2 months (15 years~20 years 5 months). The majority of preoperative diagnoses was avascular necrosis of femoral head with 52 cases (80%), followed by osteoarthritis with 7 cases (11%) and the other 6 cases. Used as acetabular components were 15 cases of the Expansion cup, 26 cases of the HG II cup, 11 cases of the CLW cup, 2 cases of the Spherical cup and 11 cases of Bipolar cup (54 cases of the total hip arthroplasty and 11cases of bipolar hemiarthroplasty).

Results: No femoral stem revision was performed. The average Harris hip score improved from 52.2 preopera-tively to 94.3 at the final follow-up. There was no patient who complained a severe thigh pain. Radiographically, small osteolytic lesions were found in 23 cases (35.4%), endosteal bone formation in 63 cases (96.9%), calcar femoral atrophy in 7 cases (10.8%) and cortical hypertrophy in 15 cases (23.1%). Acetabular cup loosening occurred in 4 cases and liner dissociation occurred in 2 cases among 54 total hip arthroplasty cases, and the acetabular cup revisions were performed in those cases and a liner change was additionally performed in 1 case. The conversion total hip arthroplasty was performed in 1 case among 11 bipolar hemiarthroplasty cases due to a snap fit design failure. Complications included a periprosthetic fracture (1 case) and a dislocation (1 case). The periprosthetic fracture, which was complicated due to a slip-down injury 17 years after the THA, was treated by an open reduction and internal fixation. The dislocation, which was complicated 13 years after THA, was treated by a manual reduction.

Conclusion: Fifteen to twenty year follow-up results of total hip arthroplasty using the CLS femoral stem showed an excellent result without any femoral stem revision.