Researchers have discovered a new technique that stimulates important nerve cells in the spinal cord to offer hope to paralysed patients.
In a possible breakthrough for the treatment of spinal-cord injuries, an American man Rob Summers from Oregon who was paralysed from below the chest after being hit by a car is now able to stand and move a bit with electrical stimulation coupled with strong physical rehabilitation of his spinal cord.
The combination of electrical stimulation and physical rehabilitation was previously considered to work only in animals. As this is the first such achievement in humans, so researchers remain cautious.
The breakthrough was a consequence of teamwork by neuroscientists at the University of Louisville, University of California, Los Angeles and the California Institute of Technology. The research, published in this month’s issue of The Lancet, has been funded by the National Institutes of Health with extra support provided by the Christopher and Dana Reeve Foundation.
How it works
Before getting the spinal implant, which is also known as an epidural stimulating array, Rob Summers went through two years of training on a treadmill with a harness supporting his weight while researchers helped move his legs. The training did not progress Rob’s paralysis. However, Rob underwent a surgery to implant a device with 16 electrodes placed on the key spots on the spinal cord. After receiving the spinal implant and a couple of weeks’ training, Rob was able to stand up using his own leg muscles while holding on to bars for support. With the help of a harness support and some therapist assistance, he gradually started to make stepping motions on a treadmill. Eventually Rob was successful in voluntarily moving his toes, ankles, knees and hips on command. He was also able to get back some bladder and sexual function too.
It should be noted that Rob had some sensation in his lower extremities after his accident. This means that the spinal cord was not entirely severed, which may have affected the success of his recovery.
However, when the electrical stimulation was turned off, Rob had no voluntary control over his limbs. But if the technique could be replicated in future studies, patients with spinal-cord injuries could potentially use a transportable stimulation unit equipped with a walker, and stand without any support, maintain balance and even take a few steps.
Study co-author Reggie Edgerton, department of integrative biology and comparative physiology at UCLA, says the brain frequently sends signals to the spinal cord to produce basic movement, and stimulation primes nerve cells that, even devoid of the brain, can accept sensory information and act on it too.
Susan Harkema, study co-author and rehabilitation-research director at the Kentucky Spinal Cord Injury Research Center (1) at the University of Louisville has stated that further research is essential on more-complicated stimulation devices, as the present one is usually used in pain control. There could also be some potential of introducing drugs to further sensitize neural circuits in the spinal cord.
Not a definite cure
This technique is no way a definite cure for paralysis, according to UK experts. It also isn’t clear whether the stimulation could induce movement in patients whose spinal cords were fully severed.
The FDA has given the research team consent to test five spinal-cord injury patients to check if the findings can be repeated. In succeeding trials, patients who experience no sensation will be fixed with the device, to ensure if this has any effect on the outcome.
Professor Geoffrey Raisman, Institute of Neurology at UCL (2), clarifies that this procedure is not and does not claim to be a cure, and cannot be judged on the basis of one patient and insists future trials are needed to know its benefits.
The condition of paralysis
Paralysis is the inability to move a part of the body due to injury or disease. It refers to a loss of movement than just weakness. The problem starts off in the nerves to the muscles rather than in the muscles themselves. Sometimes doctors do not stick to this rule and often use paralysis to portray a feeble limb which is capable of some movement. They also talk about paralysis is caused by diseases of the muscles rather than the nerves.
According to a study started by the Christopher & Dana Reeve Foundation (3) there are about 1 in 50 people living with paralysis – approximately 6 million people.
There are still many technological questions to be answered before spinal stimulation could be considered for the masses. Spinal-cord injury experts are optimistic that if the work withstands further research, it could pave the way to new therapies that could improve the outlook for paralysed patients.
Dr Melissa Andrews, from the Cambridge Centre for Brain Repair (4), said that the study was an amazing discovery and feels there is good possibility to make further inroads.
Ronald Reeves, vice chairman of the department of physical medicine and rehabilitation at the Mayo Clinic in Rochester states that there is convincing scientific evidence that you can, with the electro stimulation of the spinal cord, create a positive motor response.
1) Kentucky Spinal Cord Injury Research Center
2) Institute of Neurology at UCL
3) Christopher & Dana Reeve Foundation
4) Cambridge Centre for Brain Repair