Nerves are electrical conductors, sending messages to and from your brain. You feel pain, heat, cold, and other sensations with nerves. You walk, run, laugh, and even remember to pick up the dry cleaning because of the nerves in your body. Sensory nerves send messages about your environment to the brain (i.e. the iron is hot), which "listens" to the messages. Your brain then makes a decision and sends the appropriate action to your muscles through motor nerves (i.e. pull your hand away from the iron).
Injury or disease can disrupt the messages that your nerves carry to and from your brain. This disruption may cause pain, weakness, or numbness in the back, neck, arms, hands, or legs. Electrodiagnostic testing helps pinpoint the problem, resulting in faster, more effective treatment. Two commonly used tests, offered at VOA, are electromyography (EMG) and nerve conduction studies (NCS).
During an EMG, sterilized small needles evaluate the electrical activity in your muscles. An EMG allows a physician to see and even listen to muscle activity, which helps the physician determine if the muscle is functioning normally.
NCS are used to determine if nerves are working correctly. NCS are often done with an EMG. During NCS, electrodes are taped to the skin over the muscles being tested. A small electrical current is sent to your nerves through the electrodes. The faster the electrical current travels through the nerves, the healthier the nerves. Weakened or damaged nerves will produce slower, weaker signals.
According to the American Academy of Orthopaedic Surgeons, common conditions that often require electrodiagnositc testing to diagnose include:
- Carpal Tunnel Syndrome: The median nerve travels from the forearm to the hand through the carpal tunnel in the wrist. Carpal tunnel syndrome occurs when the median nerve is "squeezed" at the wrist, resulting in numbness and tingling in the hand.
- Ulnar Nerve Entrapment: Also called cubital tunnel syndrome. When you hit your elbow or "funny bone," you feel a tingling sensation because you disturbed the ulnar nerve. This long nerve extends down the arm, behind the elbow, and into the hand, through the cubital tunnel. The ulnar nerve is responsible for feeling and muscle activity in the little and ring finger, and many muscles in the hand. Injury to the elbow may cause the ulnar nerve to swell and become "trapped" in the cubital tunnel.
- Cervical Radiculopathy: Radiculopathy refers to pain "radiating" from the cervical area, or neck, typically caused by pressure on the nerve "roots" as they leave the spinal column near the neck.
- Thoracic Outlet Syndrome: The space between your collarbone and first rib is called the thoracic outlet. This tight space consists of many blood vessels, muscles, and nerves. Thoracic outlet syndrome occurs when the shoulder muscles are not strong enough to hold the collarbone in place, and it "slips" down, putting pressure on the blood vessels, muscles, and nerves in the thoracic outlet.
If you are experiencing pain, weakness, or numbness in the back, neck, arms, hands, or legs, it is important to identify and treat the cause. Talk with your primary care physician about a referral to Valley Orthopedic Associates for electrodiagnostic testing, or call VOA at 425-656-5060.
Electrodiagnosis & Spinal Injections - Physicians
American Academy of Orthopaedic Surgeons
North American Spine Society