My 17-year old son was sliding into home plate when his foot hit against another player. His knee dislocated and he had surgery to repair the damaged ligaments. There’s some concern about nerve damage. How can we tell if there is a nerve injury?

Doctors will use measurements of muscle size, muscle strength, and symptoms as a guide. Each nerve provides information about sensation and controls muscle contraction. Change in either of these functions can signal nerve damage.

Electromyography (EMG) studies can give good information about the condition of the nerve. Serial EMGs (doing more than one) help track recovery over time. Nerve tissue regenerates at a rate of about 1 millimeter each day. This is equal to approximately one-half an inch in a month’s time. If there is no sign of nerve recovery three months after the injury, surgery may be advised.