Imagine the plight of a young person, the sole bread-earner in the family, getting paralysed below the neck as a result of a road accident, with no movement or sensation in all four limbs and no control over his bowel and bladder. This poses a big physical, psychological and economic challenge not only for the individual but also for the whole family.
Spinal injuries on the rise
The ever increasing vehicular as well as pedestrian traffic on our already overstrained roads has conspired towards increasing the number of such unfortunate individuals sustaining spinal cord injuries. What makes it really unfortunate is the fact that those who sustain a complete injury (no motor or sensory function below the level of injury) generally do not recover any function, i.e. there is no cure available for such injuries.
This is because unlike the cells of other parts of the body, the neurons (the cells of the spinal cord) do not have the capability to regenerate usefully and resume their function. The goal of management in such patients is to train them to lead a near normal lifestyle from the wheelchair. This involves physical, psychosocial, sexual and vocational rehabilitation as well as integration within the community.
Stem cell research
No wonder then that such a lot of research around the globe has been focused on this field, a lot of it promoted and funded by famous individuals like Christopher Reeves who themselves sustained such injuries.
A significant proportion of this research has involved stem cells. These cells differ from other kinds of cells in the body and have three general properties: they are capable of dividing and renewing themselves for long periods; they are unspecialised; and they can give rise to specialised cell types including spinal cord cells.
Ongoing stem cell research focuses on various ways that may contribute to spinal cord repair:
- Replacing the neurons that have died as a result of the injury.
- Generating new supporting cells that will reform the insulation of the cells (myelin) and stimulate the regrowth of damaged nerves.
- Releasing protective factors to protect the cells at the injury site from further damage shortly after injury.
The potential of stem cells to treat spinal cord injury is being investigated eagerly, but there are many things about stem cells that researchers still need to understand.
Animal trials with various types of stem cells have shown very encouraging results. However, early trials in humans have not been able to replicate these results. Even though resear-ch continues on a very large scale, a clinical breakthrough continues to evade researchers. The practice of some clinicians to offer still experimental stem cell therapies to desperate patients as a cure, needs to be condemned, since the benefits are not clearly established unlike some adverse effects which are well known.
The writer is Chief of Spine Service & Medical Director, Indian Spinal Injuries Centre, New Delhi