Hand Surgeon Presents the Case for Early Tendon or Nerve Transfers in Elbow Injuries
In this article, nerve injuries around the elbow affecting hand function are the focus. The authors walk us through injuries for each of the three major nerves in the elbow, forearm, and hand. These three nerves (radial, ulnar, median) can be cut, pinched, crushed, or stretched in ways that leave the hand useless or less than functional.
Knowing when to repair the problem versus reconstruct the damaged anatomy is a challenge for the hand surgeon. Use of nerve or tendon transfers early is advised with there are signs that motor function won't occur, rehab will be lengthy, or recovery just isn't possible.
Nerve transfers as a treatment option aren't new but recent improvements in the way this surgical procedure is done has made it a more viable option now. Patients gain better and faster improvements when the procedure is done early on after injury. And the recent success with nerve transfers comes without the need for long, extensive retraining afterwards.
The type of injuries discussed in this article includes high-energy, traumatic cuts to the nerves. These injuries are usually the result of accidents with knives, saw blades, or hunting rifles. When planning treatment and considering all the options, the surgeon tests each patient's sensory (feeling) and motor (movement) function below the level of the nerve injury.
All muscles (and their attached tendons) are tested for loss of function against gravity and against resistance. Grip and pinch strength are measured. Special tests for sensation are carried out. The results of all these tests can serve as a baseline against which treatment results can be compared. The tests are easily repeated anytime along the way.
Surgery isn't always needed for nerve injuries. Some patients recover completely with time and hand therapy. But if several months go by with no improvement or only minimal recovery, then it's time for the hand surgeon to take a second look.
Special neurodiagnostic tests can be ordered to see if and how much the nerves are firing. The results of these tests along with clinical observations is often enough to suggest the need for surgery to repair or reconstruct the damaged area.
Time is still an important factor in recovery. Nerves recover very slowly at a rate of about one inch each month. After 18 months without nerve stimulation, the motor endplate (junction where the nerve connects to relay messages) starts to degenerate. If the nerve gets there too late, the patient won't regain motor control. In other words, the muscle doesn't get the message to contract and use of the hand is limited.
In cases where it looks like recovery will be delayed too long, the surgeon has the opportunity to perform a tendon or nerve transfer. This means a piece of tendon or nerve from another area of the elbow or forearm is used to replace the damaged structures. Often there are extra branches or even duplicate fibers that can be used without damaging the donor tissue.
The location of the nerves and anatomy around the nerves are often direct factors in nerve injuries. For example, the radial nerve is close to the bone so any bone fractures near the nerve can end up cutting the nerve. The ulnar nerve is susceptible to scarring because of the thick fascial structures around it. Once damaged and no longer able to move, slide, and glide, the connective tissue can close around the nerve further constricting it.
The authors discuss timing and technique for these transfers for each of the three nerves around the elbow (radial, ulnar, median). They describe which tissues are used to replace these three nerves and tendons affected by them.
Reviewing studies reporting results from using these transfer techniques, they report excellent outcomes with almost normal finger and hand function. Factors that affect outcomes include patient age, time between injury and surgery, and extent (severity) of damage.
The authors conclude by saying that nerve injuries high up around the elbow can cause significant paralysis with loss of sensation and function of the hand. Early nerve and tendon transfers when indicated by testing can provide the return of significant hand and finger function. And that is vitally important for people who require specific hand functions for their jobs or life activities.
Reference: Andrew R. Tyser, and Kenneth R. Means, Jr, MD. Nerve Injuries About the Elbow: Treatment Options. In Current Orthopaedic Practice. January/February 2012. Vol. 23. No. 1. Pp. 29-33.