Efficacy and safety of bone marrow-derived cell transplantation for spinal cord injury: a systematic review and meta-analysis of clinical trials.

PURPOSE: Bone marrow-derived cells (BMDCs) for clinical transplantation were carried out many years in treating spinal cord injury (SCI) without a clear conclusion. This study aimed to evaluate the safety and efficacy of BMDC transplantation in treatment of SCI patients. METHOD: Electronic databases, including PubMed, EMBASE, MEDLINE, and the Cochrane library, were searched to identify clinical therapeutic trials studying the application of BMDC transplantation in SCI. RESULTS: Overall the quality of the 24 studies was low, including one Grade I level of evidence, six Grade II levels, three Grade III levels, and 14 Grade IV levels. With a maximum of six-yr follow-up, the procedure-related complications were minor and temporary, without serious adverse events (p = 0, n = 594). AIS improvement rate was analyzed in favor of BMDCs 6.13 (95% CI, 3.0-12.51; p < 0.001). In patient with complete (AIS A) and chronic SCI, the application of cell transplantation numbers between n × (10(7) -10(8) ) seemed to be more beneficial (p < 0.05 for all groups). CONCLUSIONS: Based on short-medium terms following up, BMDC transplantation appears to be safe and valid in SCI patients, more effective in chronic and complete injury. Nonetheless, prospective, randomized trials in larger cohorts are still needed.