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Updated: Feb 7, 2026

Individualized Stem-positioning in Calcar-guided Short-stem Total Hip Arthroplasty
Published on: February 27, 2018
Is Hip Center Elevation an Acceptable Choice for Total Hip Arthroplasty for Legg-Calvé-Perthes Disease? Perioperative
Min Uk Do1, Kyeong Baek Kim1, Sang-Min Lee1
1Department of Orthopedic Surgery, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Pusan National University School of Medicine, Yangsan, Korea.
Background:
When positioning the acetabular component for total hip arthroplasty (THA) in patients with sequelae of Legg-Calvé-Perthes disease (LCPD), elevating the center of rotation (COR) of the hip is often unavoidable. We aimed to compare the outcomes between the preserved and elevated COR groups in patients with sequelae of LCPD.
Methods:
We enrolled 53 patients who underwent primary THA for sequelae of LCPD between 2006 and 2019. Patients were divided into 2 groups based on the postoperative COR position: 19 in the preserved COR group and 34 in the elevated COR group. The mean elevation of COR was 2.7 mm (range, 0-5.0 mm) in the preserved COR group and 8.1 mm (range, 6.0-12.0 mm) in the elevated COR group. Radiological outcomes, such as osteolysis and implant loosening, were evaluated. Additionally, reoperation, perioperative complications, limping gait, pelvic obliquity, and the modified Harris hip score (mHHS) were assessed.
Results:
There were no significant differences in radiological or clinical outcomes between the 2 groups. Neither osteolysis nor implant loosening was observed, and no reoperations were required. Intraoperative periprosthetic femoral fractures occurred in 3 cases (6%), but no cases of sciatic nerve palsy were observed. Residual limping gait was noted in 10 patients (19%), and pelvic obliquity persisted in 8 patients (15%). At the last follow-up, the mean mHHS was 89.2.
Conclusions:
The 5-17-year follow-up results of primary cementless THA in patients with sequelae of LCPD were satisfactory. Furthermore, a moderate elevation of the COR, with a mean of 8.1 mm (range, 6.0-12.0 mm), did not significantly affect the outcomes of THA in these patients. Therefore, a moderate elevation of the COR can be considered an acceptable option for patients undergoing THA with sequelae of LCPD.
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