Clinical Follow-up Study of the Reconstruction of the Femoral Head With Transferred Vascularized Greater Trochanter Bone Graft for Association Research Circulation Osseous III–IV Osteonecrosis of the Femoral Head

PURPOSE: The aim of the study was to investigate the curative efficacy of osteonecrosis of the femoral head (ONFH) in a hip-preserving operative approach, by transferring a vascularized greater trochanter graft combined with osteotomy of the upper third of femoral head, in an attempt to seek an innovative approach for patients who experienced middle- to late-stage ONFH with femoral head's weight-bearing area severely collapsed. METHOD: Our research included a total of 23 patients (23 hips) who accepted hip-preserving surgery by reconstructing the femoral head with transferred vascularized greater trochanter bone graft for ONFH from January 2013 to December 2017. The definition of reconstructing the femoral head is that we do the osteotomy on the upper third of the femoral head with weight-bearing area severely collapsed, and the remnant femoral head requires a hemispherical bone graft to recover the shape. A vascularized greater trochanter bone graft was next transferred and fixed at the upper portion of the remnant femoral head, and then, the shape and vascular supply of the femoral head are successfully reconstructed. The clinical assessment was performed with Harris Hip Score system. Kaplan-Meier survival curves with femoral head collapse as the end point showing the probability of progression in collapsed femoral head based on the gender, age and body mass index. RESULTS: Twenty-three patients (23 hips) were eventually contacted by telephone for an outpatient clinic follow-up, with a mean follow-up time of 41.35 months (varied from 16 to 72 months), no patients lost contact. Seven patients (7 hips) had radiographic stage progress. One patient (1 hip) had conversion to total hip arthroplasty at 24 months postoperatively because of progressive femoral head collapse and severely pain. The image success rate was 69.6%, clinical success rate was 65.2%, and the clinical survival rate was 96%. The average Harris Hip Score was 82.5 ± 5.5 points at the last follow-up, representing a great improvement compared with the 51.9 ± 7.2 points obtained preoperatively (P<0.05). Kaplan-Meier survival curves with femoral head collapsed as the end point showing the probability of progression in collapsed femoral head based on the sex, age, and body mass index. CONCLUSIONS: Reconstructing the femoral head with transferred vascularized greater trochanter bone graft provides a new method for the treatment of the young Association Research Circulation Osseous stage III-IV ONFH patients with severely femoral head collapsed, which can better improve the patient's symptoms, the quality of life, and delay the age of undergoing arthroplasty in young patients.