Intradiscal mesenchymal stem cell therapy for degenerative disc disease: a systematic review and meta-analysis of randomized trials

Study Design: Systematic review and meta-analysis.Purpose: To investigate the efficacy and safety of intradiscal mesenchymal stem cell (MSC) injection for patients with degenerative disc disease (DDD).Overview of Literature: DDD is a common cause of chronic low-back pain (CLBP).Studies have shown that MSC therapy may have the potential to reverse the degenerative process.However, the evidence remains inconclusive.Methods: A comprehensive search of Europe PMC, Cochrane Library, Scopus, and Medline was conducted up to April 30, 2025, using relevant keywords.Randomized controlled trials (RCTs) comparing intradiscal MSC injections with sham/placebo in patients with DDD were included.Random-effects models were used to calculate the odds ratios and mean differences (MDs).Results: Seven RCTs were included.MSC injection was associated with significantly greater reductions in Visual Analog Scale pain scores (MD, 6.67; 95% confidence interval [CI], -9.31 to -4.02; p<0.00001,I 2 =29%) and Oswestry Disability Index (ODI) (MD, -4.05%; 95% CI, -5.24 to -2.87; p<0.00001,I 2 =32%) compared with sham/placebo.The magnitude of improvement increased with longer followup.No significant differences were observed between groups in treatment-emergent adverse events (AEs), serious AEs, treatment discontinuation due to AEs, or mortality.Conclusions: Intradiscal MSC injection appears to be a safe and effective therapy, offering modest improvements in pain and function for patients with CLBP due to DDD who do not respond to conservative treatments.