Background: Cell-based therapies represent one of the definitive treatment approaches to SCI which, to become a routine clinical application, is marred by several known unknowns. The Bone Marrow Mononuclear Cells (BMMNCs) and Mesenchymal Stem Cells (MSCs) represent the most clinically applied cell types for SCI in humans, with safety established, and to an extent, efficacy reported. Methods: In this review, we have analysed the clinical studies performed using BMMNC and MSC for complete SCI separately, and the potential for applying those cells in combination. We have also analysed those factors whose outcome in animal studies of SCI could be evaluated in depth but the clinical outcome cannot be evaluated intrinsically owing to practical difficulties. Conclusion: A combination of these two cell types, BMMNC and MSC, has been proven to be advantageous than applying them separately. Therefore, a thorough evaluation including the rationale and potential implications of applying these two therapies has been presented here, and we hypothesize that such a combination is likely to improvise the outcome of a wholesome approach to spinal cord regeneration after SCI.