One prospective randomized controlled trial in human subjects has been performed for acute stem cell transplantation after SCI. In their pilot study, Chhabra et al. (2016) recruited 21 individuals who had undergone surgical stabilization and/or decompression for AIS A injuries. They performed either intralesional, intrathecal, or no injection of autologous stem cells. Notably, stem cell transplantation was performed as a second procedure, at 10-14 days post injury, after the primary surgery had been performed. In this study, there was a similar safety profile between groups, with no differences in complications, and similar improvements in functional status measured in each group. There was no difference in neurological recovery, electrophysiological data, functional status or urodynamic profiles between groups at 6 or 12 months.
An additional case series from China (Akbary & Arora, 2014) reported on the simultaneous transplantation of autologous bone marrow at the time of the primary surgery in ten AIS A individuals. At six-week follow-up, two individuals demonstrated some improvement in AIS sensory scores, but no individual demonstrated any motor or functional improvement at 6 weeks or 3 months.
There is level 1b evidence (based on one randomized controlled trial; (Chhabra et al., 2016), and one pre-post study; (Akbary & Arora, 2014) that autologous bone marrow transfer is not effective in promoting neurological or functional recovery in individuals with traumatic SCI.