Wednesday May 16 2012
Nerve 'bypass' provides hope for spinal cord injury
Revolutionary surgery has given a paralysed man the ability to move his arms and hands again, it has been widely reported. The surgery, which made global news, has shown that rewiring nerves may allow surgeons to restore basic arm and hand control after serious spinal cord injuries.
A 71-year-old patient had been left paralysed from the neck down after the base of his neck was injured in a traffic accident. In a world first, surgeons were able to successfully bypass the injury site by grafting arm nerves from below the injury to nerves originating above the site of his injury. The surgery was given 23 months after his accident, and after several more months of therapy and training the man can handle objects, feed himself and even do basic writing.
This success story is clearly of massive significance to the man involved but also provides a blueprint for other surgeons around the country for how this technique may be applied in similar situations.
However, despite this fantastic success, it is important to bear in mind that this was an individual case, and it is not clear whether this technique will be equally successful in other patients with different types of spinal injuries or circumstances. The severity and location of the spinal cord injury are likely to be important factors in the success of this type of operation.
Where did the story come from?
The research was detailed in a report written by researchers from the Division of Plastic and Reconstructive Surgery and the Department of Neurological Surgery at Washington University School of Medicine in St Louis, Missouri in the US. The case report was published in the peer-reviewed Journal of Neurosurgery. The report did not specify any sources of funding for the research.
This story received widespread media coverage and many papers reported on the restoration of function in a previously paralysed man. The coverage of the story was generally well balanced and reflected the case report accurately.
What kind of research was this?
This case report described a surgical technique designed to restore nerve function to the arms and hands of a 71-year-old man who had been injured in a road traffic incident and left paralysed. The patient had experienced severing of the spinal cord at the top of his spine, causing him to be paralysed below the site of his injury. This meant the paralysis affected his arms and hands, as the nerves that control the arms are situated below the site of his spinal cord damage.
In this cutting-edge research surgeons created a 'nerve bypass' by grafting a working nerve originating in the spine above the injury site to the nerves in the lower arm originating below the injury site to restore some level of control lost following the injury.
Spinal cord injury (SCI) is devastating for the individuals affected and their families. Recovery from a complete SCI is rare, leaving most patients with significant permanent disability affecting the area below the site of the SCI. Despite advances in understanding the processes that occur in short- and long-term SCI, corresponding advances in surgical techniques or applications to repair them have so far lagged behind.
Case reports are often published that share interesting developments or new techniques in a particular medical field, in this case surgery. Case reports provide a detailed description of the background of a single person and the treatment they received, along with how effective the particular treatment course has been. They do not necessarily reflect what will be seen in all patients treated with the same techniques in the future, but still provide a good insight into new or experimental techniques.
What did the research involve?
The right-handed 71-year-old man presented to a surgical department 22 months after he was injured in a motor vehicle accident. He had sustained a spinal injury to the lower part of his neck, called the C7 vertebra. This caused extensive paralysis below the injury site. The strength and mobility of his limbs were extensively assessed to see if surgery might be able to help. Before surgery, he could flex his right wrist only weakly and could not pinch or grip with either hand. He could also not move his fingers on either hand.
A month after his initial assessment, the patient had surgery on both arms in a bid to restore some of the function of his hands. This was based on the concept that a working nerve originating in the spine above the injury site could be grafted onto the nerves in the lower arm to restore some of the control lost after the injury. The 'nerve transfer' surgical technique involved taking a working nerve in the upper arm that originates from the C6 vertebral level (above the site of the injury), and joining it to the nerve system in the arm that originates from the C7 vertebra (the site of the injury).
This 'nerve rewiring' allowed working nerves above the spinal injury site to artificially connect with nerves below the injury site, which were previously unable to receive a signal due to the injury. Nerve transfer for spinal injuries is not new, but its application has so far been relatively limited.
After the surgery, the patient received continued hand physiotherapy to aid recovery and rehabilitation of the wasted hand muscles due to the injury.
What were the basic results?
During the operation, the surgeons stimulated the newly rewired nerves to check they were working and found that the nerve responses were essentially normal for the rewired nerves feeding the hand.
Eight months after the operation, the patient was able to move his left thumb and perform a pinching motion with his fingers and thumb in his left hand. The same increase in movement was achieved in the right hand after 10 months.
The authors report that he can now use his right hand to perform simple 'hand to mouth movements', and with his left hand he can feed himself and perform rudimentary writing activities. Recovery in the right hand has been slower than in the left.
Videos made available by the study group show that the man is now able to handle a ball with both hands, touch his fingers against his thumb in a pinching motion and feed himself. These were all activities he could not do before the surgery.
How did the researchers interpret the results?
The researchers said that, to their knowledge, this is the first reported case of restored nerve control of the thumb and finger flexing movement after a spinal cord injury.
They also said the patient’s 'function has improved significantly with his ability to feed himself'.
This case report represents the positive experience of a paralysed 71-year-old man who has been granted some manual control after a serious spinal injury to his neck. Before surgery, he could only make minimal arm movements controlled by the nerves above his injury site, but no lifting or fine hand movements as they are controlled by nerves joined lower down the spine, below the site of his injury.
While the nerve transfer technique given to this patient is not new, its application is not widespread and the authors say this is the first time it has been used to successfully rewire the nerves supplying a hand. Furthermore, these gains occurred after surgery that was carried out 23 months after the injury was sustained. This suggests that surgery does not have to be performed immediately, and that it may be possible to carry out the technique in people who have been paralysed for some time.
In addition to the hugely significant benefits to the man involved, this success story has also created a blueprint for other surgeons around the country for how this technique may be applied in similar cases.
However, it is important to bear in mind the limitations of the surgery and the evidence of its effectiveness. This case report represents the experience of just one individual. Therefore, it is not clear whether this technique will be equally successful in other patients with different types of injuries or circumstances. The severity and location of the spinal cord injury are likely to be important in determining the relative success of this type of operation. Also, the level of strength and control achieved in this case did not appear to represent a complete restoration of arm function, although it was clearly still a massive improvement.
Analysis by Bazian. Edited by NHS Choices.