Bone Marrow Transfer

After traumatic SCI, secondary neurologic injury happens in large part because of cellular-level events including demyelination and axonal degeneration. Bone marrow, with its associated pluripotent stem cells, is purported to enhance the cellular milieu for neuronal regrowth. This therapeutic option has an undeniable theoretical appeal. To date, a very limited number of human studies have been performed with mixed results. Generally, stem cell therapy enjoys a wide and sometimes over-enthusiastic public profile in terms of clinical therapeutic potential, and these studies should help contextualize the current level of efficacy in traumatic SCI.

Author Year

Country
Research Design
Score
Total Sample Size

Methods Outcome
Chhabra et al. (2016)

India

RCT

PEDro=7

NInitial=21 NFinal=21

Population: Mean age=52 yr; Gender: male=16, female=6; Level of injury: T1–T12; Severity of injury: AISA A.

Intervention: Participants were randomized into three groups to determine the safety and feasibility of autologous bone marrow transplantation in individuals with acute SCI. Two groups underwent autologous bone marrow cell transplantation through the intrathecal (n=7) or intralesional group (n=7), whereas the third served as a control (n=7). Outcome measures were assessed at baseline, six and 12 mo post enrollment.

Outcome measures: Adverse events; Motor score; ASIA score; Walking index of spinal cord injury (WISCI); EMG; Spasticity; Urodynamics; SCIM.

Chronicity: The range of time from injury to surgery was 24 hr to 5 days.

1.     Surgery was well tolerated by all participants.

2.     No significant adverse events were attributable to the procedure.

3.     There was no significant improvement in the neurological, electrophysiological or urodynamic efficacy variables between groups (p>0.05).

4.     A statistically significant improvement in functional scores as measured by SCIM was observed in all groups (p<0.05).

Akbary & Arora (2014)

China

Pre-Post

N=10

Population: Mean age: 30.3 yr; Injury etiology: fall=8, struck with object=2; Level of injury: lumbar; Level of severity: AIS A; Mean time since injury: 6.1 days.

Intervention: Individuals who had sustained a traumatic dorsolumbar vertebral fracture with complete paraplegia were recruited for this study. At the beginning of surgery, 100 ml of bone marrow was extracted. After surgical decompression and stabilization, the bone marrow isolate was injected into the site of injury. Outcomes were measured at 6 wk and 3 mo.

Outcome Measures: American Spinal Injury Association (ASIA) scores, Frankel Grade.

1.     Two individuals showed some improvement in terms of the ASIA scores in but no improvements in their Frankel Grade at 6 wk. No improvements were seen at 3 mo.

2.     Eight individuals showed no improvement in terms of the ASIA scores or Frankel Grade at 6 wk or 3 mo.

Discussion

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.

Conclusion

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.