Electrodiagnostic Studies

Anatomical changes to the spine that cause nerve impingement, either in the spinal cord itself, or in the nerve roots and nerve branches that exit the spine, are of the biggest concern to a person's health. Impingement (compression) of the nerves can cause a person to lose feeling or even motor control of the extremities that nerve branch supplies. If the nerve that supplies an area is compressed for extended periods of time, muscles and other organs may atrophy, and eventually the damage could become irreversible. back pain which is associated with nerve root compression is the biggest reason for back surgeries, due to the immediate need to remove the cause of compression in order to avoid permanent damage. Nerve pain may also be caused by two other reasons.
  1. Neuropathic pain. There are neurologic conditions when nerves in the body are not affected by the injury to the surrounding structures around it. Neuropathic pain includes conditions where the nerves fire pain signals to the brain in spite of the fact that they aren't being compressed. With neuropathic pain, the nerves just fire pain signals despite the fact that they aren't being compressed and in the absence of any stimulus telling it that an injury has occurred in that area of the body.
  2. Disease. Due to certain conditions that cause destruction to the nerves themselves, the nerves may misfire pain signals to the brain or fail to function properly at all. Diabetes is one of the primary causes of neuropathy - nerve pain. Other disease conditions that may adversely affect the nerves, causing back pain and nerve pain, include HIV infection, multiple sclerosis, shingles, or spinal surgery.


We smoke to much, get fat too much, get old too much, and sometimes are just unlucky too much. For this reason, a person with back pain may have multiple areas of the back that could possible be the true cause of the person's pain, as well as disease conditions that also could be involved. Tests such as MRIs and CTs are good at showing degenerative spine conditions, soft tissue anatomy, and associated nerve impingement that results. Other types of tests, both hands on and high tech, may be done to measure which nerves have been disrupted as a result of injury, age related changes or disease. Nerve tests, also called electrodiagnostic studies, are used to determine whether the electrical activity of nerves has been disrupted as a result of problems in the back. Electromyography is the most common test used to confirm the disruption of specific nerve branches as the primary cause of back pain.

Electromyography (also called a myogram or EMG) is a test that involves the insertion of a needle into certain muscles, and the subsequent evaluation of the health of the nerve that supplies that muscle, based on the amount of electrical activity that is detected in that muscle. In this tests, a needle is inserted into the muscle, and the strength of electrical activity in that muscle is recorded. After several weeks of pressure on a nerve root, the muscles that nerve root supplies will begin to contract spontaneously. This is one of the primary reasons patients feel muscle pain due to back pain. The electrodes may detect spontaneous muscle contraction as a result of nerve root compression. The electrodes may also detect a slower rate of electrical conduction as a result of prolonged nerve root compression. These tests may also help neurologists to distinguish between nerve pain due to nerve root compression (radiculopathy) and nerve destruction (neuropathy).