Nerve Injuries

What it is

Nerves are the wires that carry signals between the brain and the body. Motor fibers make muscles move, and sensory fibers carry feeling. Each nerve is a bundle of these fibers inside a protective outer layer. An injury can damage that outer layer, the fibers inside, or both, and the type of damage determines treatment and recovery.

What causes it

• Pressure: a tight spot in the body, such as carpal tunnel syndrome, or swelling after an injury
• Stretching or bruising: injuries such as a crushed finger, even without a cut
• Cuts: even a small cut, such as a knife slipping while cutting an avocado, can divide a nerve in the palm or finger

Symptoms

• Numbness, tingling, or buzzing in the area the nerve supplies
• Weakness, or muscles that shrink over time
• Pain at the injury or along the nerve
• Changes in skin color, texture, or sweating

Treatment

Treatment depends on which nerve is injured, the type and severity of the injury, how long ago it happened, and your age, health, and work. Some nerve injuries improve on their own or with splinting or therapy, and your physician may recommend a period of observation. When surgery is needed, options include:

• Decompression: releasing pressure on the nerve
• Neurolysis: removing scar tissue from around the nerve
• Nerve repair: bringing the cut ends together, or bridging a gap with a nerve graft
• Nerve or tendon transfer: using working nerves or muscles to restore function when a nerve cannot recover

Recovery

After repair, a nerve has to regrow from the injury site before it works again, so symptoms continue until it does. Injuries to the outer layer recover faster than injuries to the fibers inside. Nerves grow about one inch per month, so recovery can take a long time, and it may be complete, partial, or absent depending on the injury.