Efficacy of stem cell therapy for avascular necrosis of the femoral head: A systematic review and Meta-analysis.

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a debilitating orthopaedic condition primarily affecting younger adults, often progressing to femoral head collapse and total hip replacement (THR). Stem cell therapy (SCT) has emerged as a regenerative option to delay disease progression and preserve joint function. This study aimed to evaluate efficacy of SCT, alone or in combination with mechanical support or bone grafting, in improving clinical outcomes in ONFH.

METHODS

A comprehensive search was conducted up to November-2024. Randomized controlled trials (RCTs) comparing SCT with standard care in ONFH patients were included. Primary outcomes were THR incidence and disease progression; secondary outcomes included Harris Hip Score (HHS), Visual Analog Scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Data were pooled using random-effects models, and evidence certainty was assessed using the GRADE approach.

RESULTS

Ten RCTs involving 545 hips were included, with overall mean follow-up duration across studies was 36 months. SCT, when used in combination with mechanical support or bone grafts, showed a trend towards reduced THR risk (RR: 0.74; 95 % CI: 0.46-1.20) and significantly improved functional outcomes (e.g., WOMAC MD: -10.7; 95 % CI: -17.2 to -4.3). Pure SCT alone did not yield statistically significant benefits across most outcomes. Subgroup analyses revealed that mechanical support notably enhanced the effect of SCT on HHS and THR prevention. The risk of bias was low in six studies and high in four. GRADE assessment rated the evidence as moderate for THR and low for other outcomes due to methodological limitations.

CONCLUSION

While pure SCT appears deceptive in ONFH treatment, its combined use with mechanical support or bone grafts might be promising.