Nerve Injuries & Repair

What Are Nerve Injuries?

Nerves are your body's communication system, carrying messages between your brain and the rest of your body. Some nerves transmit signals from your brain to your muscles to create movement. Others carry sensory information about touch, pressure, temperature, and pain from your body back to your brain. Each nerve is made of thousands of tiny fibers bundled together and surrounded by a protective outer layer that acts as insulation.

When nerves are injured, this communication system breaks down. Messages can't travel properly between your brain and the affected area. Depending on which nerve is injured and how severely, you may lose sensation, strength, or both in the area served by that nerve. The hand and wrist contain many important nerves that control fine motor function and provide feeling, making nerve injuries in these areas particularly impactful.

Symptoms

The symptoms of a nerve injury depend on which nerve is affected, where along its path the injury occurred, and how severe the damage is. Numbness is common with injuries to sensory nerves. The numb area corresponds to the specific region that nerve supplies. You might lose the ability to feel light touch, distinguish temperatures, or sense pain in the affected area. This can be dangerous because you may not notice when you're burning or cutting yourself.

Weakness occurs when nerves that control muscles are injured. You may have difficulty with specific movements, depending on which muscles the nerve powers. For example, injury to the median nerve can cause trouble with thumb opposition and grip, while ulnar nerve injury affects finger coordination and pinch strength. Some people notice their hand looks different, with muscles appearing smaller if the nerve has been injured for a long time.

Pain is a frequent symptom after nerve injury. The pain can be sharp, burning, shooting, or electric in quality. It may be felt at the injury site or anywhere along the nerve's path. Some people experience tingling or a pins and needles sensation. The skin in the affected area might change color or sweat differently than the rest of your hand.

Causes & Risk Factors

Nerve injuries happen in several ways. Lacerations from knives, broken glass, power tools, or other sharp objects can completely sever a nerve. When a nerve is cut, the signal cannot jump across the gap, immediately stopping all function in the area served by that nerve. These injuries require prompt surgical treatment for the best chance of recovery.

Stretch injuries occur when a nerve is pulled beyond its normal range. This can happen during falls, motor vehicle accidents, or sports injuries where joints are forced into extreme positions. Stretch injuries vary from mild, temporary problems to severe, permanent damage. The extent of injury depends on how much the nerve was stretched and for how long.

Compression injuries result from prolonged or excessive pressure on a nerve. Carpal tunnel syndrome is a common example where the median nerve is compressed at the wrist. Fractures, dislocations, and crush injuries can also damage nerves by compressing them or disrupting their blood supply. Sometimes medical conditions like diabetes make nerves more vulnerable to injury from relatively minor compression or stretch.

Diagnosis

Diagnosis begins with understanding how the injury occurred and what symptoms you're experiencing. Your hand surgeon will ask about the mechanism of injury, whether there was a laceration or other trauma, and exactly where you notice numbness, weakness, or pain. A detailed physical examination tests sensation in specific patterns that correspond to different nerves, checks muscle strength and function, and looks for signs of muscle atrophy.

Nerve conduction studies and electromyography can help determine the severity and location of nerve damage. These tests measure how well electrical signals travel through the nerve and whether the muscles it controls are receiving signals. They can also help determine whether the injury is to a single nerve or multiple nerves, and whether the problem is in the hand, arm, or neck. Testing may be delayed a few weeks after injury to get the most accurate information about the extent of damage.

Your doctor may order blood tests to look for medical conditions like diabetes or thyroid disease that can affect nerve healing. Imaging studies like MRI can sometimes show nerve damage directly and help identify structural problems like fractures or scar tissue that might be compressing the nerve.

Treatment Options

Treatment depends on the type and severity of nerve injury. Mild compression or stretch injuries may heal on their own with supportive care. This includes protecting the area from further injury, managing pain, and maintaining joint motion while the nerve recovers. Some improvement may occur within days to weeks for very minor injuries, though more significant damage takes much longer.

More severe injuries where nerve fibers are damaged but the nerve's outer covering remains intact may heal over months without surgery. The nerve fibers must regrow along their original path, a slow process that occurs at roughly one inch per month under ideal conditions. During this time, hand therapy helps maintain joint flexibility and teaches you how to protect numb areas from injury.

When a nerve is completely cut or severely damaged, surgery is usually needed to give the nerve the best chance of healing. The sooner a cut nerve is repaired, the better the potential outcome. If you have a laceration with numbness or weakness, seek evaluation urgently. Some nerve repairs can be done as primary procedures right after injury, while others may need to be delayed or done in stages depending on the wound and other injuries present.

Surgery: What to Expect

Nerve repair surgery is typically performed as an outpatient procedure under local anesthesia, with sedation available for select cases if needed. The operation may take one to three hours depending on which nerve is injured, where the injury is located, and how complex the repair needs to be.

For a cut nerve, the surgeon carefully trims the nerve ends and sews them back together using very fine sutures under magnification. The goal is to align the nerve fibers as precisely as possible to give them the best path for regrowth. Sometimes a nerve graft is needed if there's a gap between the nerve ends. This graft, usually taken from a less important sensory nerve elsewhere in your body, acts as a bridge for the nerve fibers to grow across.

After repair, your hand may be placed in a splint to protect the nerve while it begins to heal. The position of the splint depends on which nerve was repaired and where. You'll need to limit certain movements initially to prevent tension on the repair site. Your surgeon will provide specific instructions about activity restrictions.

Recovery

Recovery from nerve injury is a slow process that requires patience. Nerve fibers regrow at approximately one inch per month in ideal conditions. For example, if the nerve was repaired at the wrist and needs to reach the fingertips, recovery could take four to six months or longer. If the nerve was injured higher up in the forearm, recovery takes even longer.

You'll receive a home exercise program that includes range of motion exercises to prevent joint stiffness and maintain flexibility while the nerve heals. These exercises are critical because stiff joints can limit function even after the nerve recovers. The program may include sensory reeducation exercises once feeling begins to return, helping your brain relearn how to interpret signals from the recovering nerve.

During recovery, you may experience tingling or a pins and needles sensation as nerve fibers regrow. This is often a positive sign of healing. Hand therapy can be helpful for learning to protect numb areas, maintaining motion, and retraining muscles as they regain nerve supply. Most people can manage their recovery with a home exercise program, though formal therapy sessions may be beneficial for complex injuries or if complications develop.

The extent of recovery depends on many factors including your age, overall health, which nerve was injured, how severely it was damaged, and how long it took to receive treatment. Younger patients generally recover better than older patients. Complete recovery is more likely when nerves are repaired promptly. Even with optimal surgery and rehabilitation, some nerve injuries result in permanent numbness or weakness, particularly when the injury was severe or treatment was delayed.

When to See a Specialist

If you have numbness, weakness, or severe pain after a laceration or other injury to your hand or arm, seek evaluation immediately. The sooner nerve injuries are diagnosed and treated, the better the potential outcome. Even if you're not sure whether a nerve is injured, any significant change in sensation or strength warrants examination by a specialist.

Dr. Lackey specializes in nerve injuries and microsurgical nerve repair. Early evaluation and treatment can make a significant difference in your recovery and long-term function.