(CSPOT42) Stem Cell Therapy in Avascular Necrosis: Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Avascular necrosis (AVN) is a debilitating condition characterized by bone tissue death, lacking effective therapeutic interventions to impede its progression. The burgeoning interest and conflicting evidence in recent literature regarding the efficacy of stem cell therapy (SCT) in AVN prompted this systematic review and meta-analysis (SRMA).

Objectives: To assess the effectiveness of various stem cell therapy in treatment avascular necrosis

Methods: Adhering to PRISMA guidelines, e-databases were systematically searched for randomized controlled trials (RCTs) assessing SCT in AVN patients. Critical outcomes, such as Total Hip Replacement (THR), Femoral Head Collapse (FHC), and Harris Hip Score (HHS), along with pain and radiographic outcomes, were evaluated. Methodological quality was assessed using Cochrane's Risk of Bias 2 tool. GRADE assessment tool used for certainty assessment of evidence. A random-effects meta-analysis model was applied, and subgroup analyses were conducted based on intervention types.

Results: The SRMA included 23 RCTs (798 patients), with 636 hips in the SCT group and 393 hips in the control group. Meta-analysis of 12 RCTs (554 patients) revealed a decrease in THR conversion rate (RR: 0.6, 95% CI: 0.3-0.9, I2=68%) and FHC (RR: 0.4, 95% CI: 0.2-0.7, I2=48%) post-SCT. HHS showed significant improvement (MD: 7.7, 95% CI: 4.5-11, I2=96%), while pain reduction with VAS was notable (SMD: 4.7, 95% CI: 0.8–8.6, I2=98%). SCT presented a non-significant reduction in WOMAC score (SMD: 4, 95% CI: -0.9-8.8, I2=97%). GRADE analysis indicated moderate certainty for THR and FHC outcomes.

Conclusions: SCT in combination with core decompression demonstrated efficacy in preserving hips, particularly in early AVN stages (I&II), reducing the risk of THR and FHC. While SCT combined with other therapies may offer additional benefits, its prioritization as the primary AVN treatment remains uncertain due to stem cell microenvironment variability. Further high-quality multicentric studies with standardized methods are essential for robust clinical decision-making.