WHAT YOU SHOULD KNOW
Injuries to the limb that damage nerves rob patients of critical functions. Nerve damage is graded on a six-point scale with higher numbers worse. Grade I and II nerve damage cannot be helped by surgery. Higher-grade injuries may benefit from surgery.Once nerve damage exists there will always be gap of some length between the healthy nerve above and the nerve target for grafting below. Even after reconnection, nerve fibers only regrow at the speed of a millimeter per day. Muscles atrophy quickly and if new nerve fibers cannot be made to reach them by a year from injury, it is usually not worth reconstructing.
MEDICAL HISTORY
The details of the original injury and any other surgeries that have been performed are critical to planning the reconstruction. The patient should bring any reports of previous surgeries.
EXAMINATION
Each of the arm’s nerve functions is specifically tested for both movement and feeling ability.
ADDITIONAL TESTS
Electrical nerve tests are valuable in confirming the findings of the physical examination and sometimes distinguishing between partial and complete nerve injuries.
TREATMENT OPTIONS
| NERVE GRAFTS | NERVE TRANSFERS | TENDON TRANSFERS | |
| CONSISTS OF | Splicing segments of the patient’s own nerves between damaged segments | Moving a working nerve from its original assignment to connect to the damaged nerve | Moving a working tendon from its original assignment to one needed to make up for one of the lost movement functions |
| FEATURES | Nerve grafts taken from the back of the leg | Done close to the targets for movement and feeling to minimize time to recovery | Only tendons that can afford to give up their original function are used |
| ADVANTAGES | The original muscles are reactivated | Reduces the long wait for recovery seen with nerve grafting | Can be done up to almost any time after injury |
| DISADVANTAGES | Only effective if done early, final function usually quite weak compared to normal | Limited source of nerves available for transfer, the brain must learn to use the new connection | Substitution with a tendon transfer can never really recreate the original lost function and the brain must learn to use the new connection |
RECOVERY
Sutures are removed in the office at 2 weeks. Limited protection on movement is observed for the first several weeks after nerve grafting or nerve transfer. The first 4 weeks after tendon transfer, protective splints are used. Tendon transfer cases continue on with motion exercises to maximize tendon functions and finish with strengthening over around a 3-month process. Nerve surgery cases have a prolonged period of waiting until evidence of functional recovery first appears. At that time, the patient re-enters therapy for specific exercises that assist in developing the nerve connections to their targets.
