Researchers here at the Department of Neurosurgery are working on an unconventional technique that gives new hope for the treatment of spinal cord injuries; spinal cord bypass surgery.
Christopher J. Winfree, M.D. from the Peripheral Nerve Center and Alfred T. Ogden, M.D. from the Spine Center, together with chief resident Raqeeb Haque, MD, and junior resident Hani Malone, MD, have just published their research in the Journal of Neurosurgery: Spine.
To understand what they are working on, it is important, first, to be able to visualize the body’s nervous system. Here is an exercise to help: Imagine a tall tree with no leaves but with four big branches coming off its main trunk; those branches, in turn, branch into ever smaller branches. Now, turn that imaginary tree upside down and bundle all the roots together into one big root ball–or brain; take the four main branches and arrange them into two arms and two legs coming off of the main trunk-or spinal cord; and you have a pretty good approximation of what the human nervous system looks like.
This system, in the human body, has an amazing capacity to heal when injured; if one of the branches is cut, even deeply, it can heal and grow back together. Unfortunately, if the trunk is cut, it will not grow back together.
The unique thing about the human body though, is that even though the trunk (or spinal cord) is severed it can remain healthy both above and below the cut. The problem is that the cut prevents the brain from communicating with the lower part.
That is why when the spinal cord is severed there is no movement below that level of injury and the disability is more than likely permanent.
What spinal cord bypass surgery is attempting to do (again using the tree analogy) is to take smaller branches from above the level of the cut, that are still healthy and in communication with the brain, bend them down across the cut, and insert them (or graft them) into the still healthy but disconnected lower part of the spinal cord. The idea is to re-establish communication between the brain and the lower part of the spinal cord, and thus regain movement and feeling below the level of injury.
The complexity of the actual procedure in question is, of course, far beyond this simple tree analogy and will take many brilliant minds and much research to figure out.
Researchers here at Columbia, including neurosurgery residents Raqeeb Haque, M.D., and Hani Malone, M.D., with neurosurgeons Christopher J. Winfree, M.D. and Alfred T. Ogden, M.D., have begun to map out the feasibility and particulars of such a procedure on human cadavers.
Their work, Spinal cord bypass surgery with intercostal and spinal accessory nerves: an anatomical feasibility study in human cadavers a Laboratory investigation,* was published in the January issue of the Journal of Neurosurgery: Spine.
Dr. Raqeeb Haque, the study’s principal investigator and Chief neurosurgery resident says, “We spent many countless hours in anatomy and cadaver labs harvesting and measuring nerves. We were looking at the anatomic feasibility of using intercostal and spinal accessory nerves as potential nerve bridges.” [The image above left shows an intercostal nerve being used in the lower spinal cord–these are long thin nerves that run along the rib cage.]
According to Dr. Haque, the results were better than expected; both nerve types were long enough to be diverted over to the spinal cord. Furthermore, he says, “Our pathology slides showed there was enough “bandwidth” for it work.” In other words, even though the nerves thinned out [like branches do as they leave the trunk] they were still thick enough to be useful for implantation.
Dr. Haque plans to continue this research and says he is cautiously optimistic that one day it will translate into an improved quality of life for those devastated by spinal cord injury. “If we can get even partial movement of hands or legs, combined with intense physical and rehabilitative therapy we can hopefully have a patient use the small movements to control a lever on a wheelchair.”
You can read the article here as it was published on-line December 2, 2011; DOI: 10.3171/2011.9.SPINE10378.
*Co-authors include Raqeeb Haque, M.D., Hani Malone, M.D., Martin W. Bauknight, B.A., Michael A. Kellner, B.A., Alfred T. Ogden, M.D., John H. Martin, Ph.D., Kurenai Tanji, M.D., Ph.D., and Christopher J. Winfree, M.D..