New Tendons Restore Hands - An In-depth Doctor's Interview
Ivanhoe.com—January 21, 2011
Scott W. Wolfe, M.D., from Hospital for Special Surgery, discusses how he was able to give one of his patients function in her hand when before she nearly had none.
Can you tell us about the condition that Nikki had that prevented her from using her hand?
Dr. Scott Wolfe: Sure. I am not a neurologist, but Nikki had a condition called transverse myelitis; I think that the closest analogy is probably polio, where the nerves that affect the muscles in any or all of the extremities are knocked out, and where the sensory nerves that give a sensation were not. That effect on Nikki resulted in the near complete loss of function in her elbow to hand on one arm.
Was she basically not using that arm at all?
Dr. Scott Wolfe: That’s correct. She could use her shoulder and her elbow, but from her elbow down it was more or less trick motions; she had a way of flipping her hand this or that way. She could do a minimum of things with only a couple of muscles in due course working in her hand – one that lifted her thumb up and one that lifted her index finger up. She had a little control of her wrist, however, it was minimal. She was limited to types of trick motions of the hand, initiated by the working muscles in her elbow and shoulder.
In a normal hand, how many working muscles are there?
Dr. Scott Wolfe: There are nearly twenty different muscles in the forearm alone; add to that another fifteen muscles in the hand. It is a very intricate balance of what we call extensors, which straighten the fingers, and flexors, which bend, as well as those that perform the wrist motions and forearm rotations.
Can you talk to us about the first procedure?
Dr. Scott Wolfe: The first procedure was to harness the ability that she had to straighten her index finger; by using that particular muscle, we could tie that into her other fingers so as she moved her index finger the rest could come along for the ride as it were. The other part of the procedure was to stabilize her thumb. So, the idea was to stabilize her thumb by fusing one of the joints at its base, to give it a stable platform for future transfers, and to enable her open her fingers together.
Can you discuss the second procedure and the difficulties that you encountered?
Dr. Scott Wolfe: For the next stage, we had to borrow two of the three muscles, and then transfer those to the palm aspect of the hand – one to close her fingers and one to close her thumb. As she used those transfer muscles, or as she would use those transfer muscles together, she would actually be able to pinch and to ultimately grasp.
How long after that second procedure was she able to see these results?
Dr. Scott Wolfe: Transverse myelitis injures the nerves, and when the nerves are injured the muscle atrophies. She was spared three or four muscles in her forearm out of those original thirty plus muscles. Within six weeks (in Nikki’s case) she was able to remap and able to bend her fingers just by thinking bend fingers rather than straighten wrist. When developing tendon transfers, we use a concept known as synergism. When you reach out to grab something, you will generally extend your wrist as you grasp your fingers. So, the brain is already partially mapped to that effect. The results are best when we use synergistic muscles, and that is in fact what we did with Nikki.
Can you discuss what you have seen so far post surgery?
Dr. Scott Wolfe: We protect someone in a cast for about four weeks. We then take the cast off and have them work with a certified hand therapist. The therapist worked closely with Nikki and helped her to learn these new tasks. That process requires two to three months...Nikki learned it in about three to four weeks.
I know that this case is unique, but could these principals be used to help other people who may suffer from a condition similar to that of Nikki’s?
Dr. Scott Wolfe: What I am doing is borrowing from tried and true techniques that have worked in the past, and actually and interestingly enough these techniques began in the days of leprosy and polio; when muscles were knocked out, and surgeons had to use new and creative ways to use existing muscles and recreate the functions lost. We are adapting some of those techniques in cerebral palsy, brachial plexus conditions and polio-like conditions such as Nikki’s. We are adapting these techniques to again match what the patient has and what the patient is missing, and try to come up with a creative solution to the problem.
For more information please visit www.hss.edu/newsroom_tendons-restore-hands-doctor-interview.asp