Analysis of the efficacy of autologous adipose-derived stromal vascular fraction and calcium phosphate bone cement combined with core decompression in patients with femoral head necrosis: a retrospective study

Osteonecrosis of the femoral head (ONFH) is a progressive disorder characterized by impaired perfusion, inflammation, neural dysregulation, and structural failure of the femoral head. While core decompression (CD) is commonly used for joint preservation, its effectiveness remains limited, particularly in the absence of adequate structural support and biological modulation. Adipose-derived stromal vascular fraction (SVF) has emerged as a potential biological adjunct due to its angiogenic, immunomodulatory, and regenerative properties. This study aimed to evaluate the clinical outcomes of combining autologous SVF and calcium phosphate cement (CPC) with CD in patients with ONFH. We retrospectively analyzed 148 patients (219 hips) with ONFH treated between 2009 and 2022. Eighty-five hips underwent CD alone (CD group), and 134 hips received SVF combined with CPC and CD (SVF + CPC + CD group). Radiographic progression and conversion to total hip arthroplasty (THA) were assessed according to the Association Research Circulation Osseous (ARCO) staging system. Hip survival was evaluated using Kaplan–Meier analysis, and multivariable Cox proportional hazards regression was performed to identify factors associated with conversion to THA. Clinical outcomes were assessed using the Harris Hip Score (HHS), visual analogue scale (VAS), and the 36-Item Short Form Health Survey (SF-36). The SVF + CPC + CD group demonstrated significantly lower radiographic progression (33.6% vs. 55.3%, P < 0.001) and THA conversion rates (20.1% vs. 35.3%, P = 0.013) compared with the CD group. Kaplan–Meier analysis showed superior THA-free survival in the SVF + CPC + CD group. In multivariable Cox regression analysis, treatment with SVF + CPC + CD was independently associated with a reduced risk of conversion to THA, whereas higher ARCO stage was associated with increased failure risk. Smoking status showed a borderline association with THA conversion. At final follow-up, patients treated with SVF + CPC + CD reported lower pain scores, improved hip function, and better outcomes in selected quality-of-life domains compared with CD alone (all P < 0.05). In this retrospective cohort, combining core decompression with structural augmentation and biological modulation using SVF and CPC was associated with improved mid-term radiographic and clinical outcomes compared with CD alone. These findings suggest that an integrated mechanical–biological strategy may offer advantages for hip preservation in selected patients with ONFH; however, prospective randomized studies with longer follow-up are required to confirm efficacy and define optimal indications.