Electromyography (EMG) and Nerve Conduction Velocity (NCV)
October 1, 2017There are many reasons our pets can have weakness and difficulty walking, including diseases of the muscles and nerves. There should be no recordable electrical activity in animals that are asleep and not moving. However, in animals with peripheral nerve or muscle disease, EMG often shows abnormal spontaneous electrical activity. EMG is used in combination with nerve conduction velocity testing and muscle/nerve biopsies to help diagnose neuromuscular disorders.
Electromyography (EMG) allows veterinary neurologists to evaluate the health of nerves and muscles in anesthetized patients. EMG utilizes small needles (<1 mm diameter) to record electrical activity within muscles. When an animal is anesthetized EMG should not identify any electrical activity within a normal muscle. EMG of animals with either muscle or nerve diseases often identifies spontaneous electrical activity, which is abnormal. This test is often followed by a nerve conduction velocity (NCV) to further isolate the abnormalities to either the muscle or of the nerve.
A muscle disease would have an abnormal EMG and a normal NCV. A nerve disease would have both an abnormal EMG and abnormal NCV.
Electromyography (EMG) is a recording of electrical activity within the muscles after placing a small needle electrode into the muscle. In people, EMG is done fully awake. Since we cannot explain to animals that they might be a little uncomfortable, this procedure is performed under general anesthesia.