Peripheral Nerve Injury in the Upper Extremity

Overview:

Nerves are the conduits of information that run from the brain to the rest of the body, and vice versa. The upper extremity contains numerous nerves that transmit stimulus for functions such as muscle contraction, sensation, and reflexes. The nerves that innervate the upper extremity leave the central nervous system through several areas in the neck, and form a complex structure called the Brachial Plexus. The nerves are larger in diameter near the neck, and eventually divide to form smaller branches in the upper arm, forearm, and hand.

Injuries to the upper extremity occasionally involve trauma to nerves, which can interfere with the various functions of the arm and hand. Occasionally, the nerve is contused, and may heal on its own in time. However, if a nerve is cut or crushed, it may need surgical treatment in order to help restore function to the hand or arm. Sometimes, certain illnesses can affect nerves and cause similar symptoms in the upper extremity.

Symptoms:

  • Note: The following symptoms are not meant to diagnose a condition. If you have these or other symptoms, you should be evaluated by a qualified healthcare provider.
  • Symptoms generally occur following an injury to the neck, shoulder, arm, or hand. Sometimes, symptoms may occur after a something as simple as laying on the arm for too long.
  • Loss of sensation in the upper arm, forearm, and/or hand. Each nerve supplies different areas of sensation in the upper extremity. The pattern of numbness can help guide the surgeon to the specific injured nerve(s).
  • Loss of function in the upper arm, forearm, and/or hand. The muscles in the upper extremity are supplied by different nerves. The muscles that do not function properly help guide the surgeon to the specific injured nerve(s).
  • Wrist drop or inability to extend the wrist.
  • Decreased muscle tone in the upper arm, forearm, and/or hand.
  • Changes in sweating patterns of the upper arm, forearm, and/or hand.

Treatment:

  • History and Physical Exam: The doctor or midlevel provider will obtain a history of the problem and perform an appropriate physical exam to find the area of concern.
  • Imaging: To test the nerves in the upper extremity, the doctor or midlevel provider may order a test called Electromyelography (EMG). This test uses needles and electrodes to test the electrical conductivity of nerves. If there was concern for a fracture, imaging begins with x-rays. If more information is needed, the doctor or midlevel provider may order a CT Scan or an MRI.
  • Surgery: The goal of surgical treatment is to improve function to the affected area in the upper extremity. Surgical treatment is decided on a case by case basis, and depends on the location, duration, and type of nerve injury. If the nerve is thought to be repairable, surgical treatment may consist of a nerve decompression, nerve repair, or a nerve graft. If the function of the upper extremity is affected and nerve repair is not an option, the surgeon may recommend a tendon transfer to the involved shoulder/elbow/wrist/digit(s).

Pre-operative Care:

  • If you have symptoms as listed above following an injury or illness, you should seek medical attention. Be sure the doctor or midlevel provider is familiar with the possible causes of these neurologic symptoms.
  • If a decision for surgery is made after seeing one of our Orthopaedic Hand Surgeons, you may require pre-operative medical clearance by our Anesthesia department or your Primary Care Provider. This depends on your other medical conditions.

Post-operative Care:

  • Recovery time is variable depending on the patient’s medical history and the surgery performed. Generally, the patient is immobilized in a cast or splint for several weeks to months, with restrictions on use of the arm.
  • After surgery, you will be placed in a post-operative dressing/splint which you must wear until your first post-operative visit with one of our providers. You must keep the dressing CLEAN and DRY to avoid risk of infection and other wound healing complications.
  • Someone should be with you for the first 24 hours after surgery.
  • You will be given a prescription for post-operative pain medicine. Do not take it with other pain medicines unless directed by your doctor. Do not drive, drink alcohol, or make important decisions while taking the pain medicine.
  • Do not smoke, use smokeless tobacco, nicotine gum, or nicotine patches. Nicotine is a vasoconstrictor, and can impede healing by limiting blood flow to the surgical site(s).
  • You must remain non-weight bearing (no use) with the surgical hand and arm until cleared by one of our providers. This may be several weeks to months, depending on your healing and the surgery performed. Your doctor will provide you with specific restrictions.
  • At the first post-operative visit, your stitches will be removed. Depending on your operative site, you may be placed in a cast, splint, or sling. If your cast becomes wet or soiled, you should come into the office for a new cast.
  • After weeks to months of immobilization, you will likely be stiff and weak in your hand. Patients are sent to an Occupational Therapist, with the goal of regaining functional use of the operative hand. Remember, you are an active participant in your care, and part of your recovery depends on your desire to participate in therapy.