Background: Cell-based therapies can be used to treat neurological diseases and spinal cord injuries. The aim of this study was to assess the clinical outcome of bone marrow derived mononuclear cells (BM-MNCs) transplantation in patients with spinal cord injuries. Methods: Following a systematic review to detect clinical intervention studies, a meta-analysis was done for pooling data to estimate the outcome of BM-MNCs transplantation. The percentage of the patients with improved ASIA scale from one grade to a higher grade was defined as the main outcome. By considering the study design and outcome measurement, two reviewers independently extracted the data. Results: Eight relevant primary studies were found; seven qualified studies, with a combined total of 328 patients were assessed by meta-analysis, including 314 ASIA-A, 13 ASIA-B, 94 cervical, 227 thoracic and 60 acute injuries. The percentage of the patients' improvement was tested by meta-analysis through random and fixed models. The overall percentage of all patients' improved ASIA scale after a one- year follow-up (95% CIs) was 43 (0.27-0.59). Conclusion: Data from published trials revealed that encouraging results were achieved by autologous BMMNCs for the treatment of spinal cord injury. However, the number of clinical trials included in the systematic review was too limited to reach a definite conclusion. More qualified clinical trials with standardized methods are needed to truly justify the outcome of this therapeutic modality in SCI patients
