Electromyogram (EMG) and Nerve Conduction Study (NCS)

Electromyogram E.M.G.

This examination is used to record and view a muscle contraction on a computer screen. This test is a commonly referred to as an E.M.G.

  • Electro (electrical)
  • Myo ( muscle)
  • Gram (graph)

The test records the electrical activity associated with the muscle contractions. E.M.G.’s are performed to determine if nerves or muscles are diseased or injured. When you come in for the E.M.G. wear loose, comfortable clothing and don’t use any lotions or oils.

WHAT HAPPENS DURING AN E.M.G.?

A very small electrode, the size of a pin, will be inserted through the skin and into several muscles. At the time the needle is inserted, you will be asked to remain very still and to relax the muscle being tested. As the test proceeds, you will first be asked to think about contracting the muscle, then you will be asked to actually contract it.

HOW THE PROCEDURE WORKS

The E.M.G. equipment records the electrical impulse that causes the muscle to contract and shows the results on a computer screen.

AFTERWARD

Although there are no aftereffects or severe pain, you may experience minor discomfort during the test and you may have a slight degree of muscle soreness for a short time following the exam.

N.C.V. (NERVE CONDUCTION VELOCITY)

E.M.G. equipment may also be used to test a nerve. In this case, a small electric shock is applied to a nerve in the arm or leg and the equipment records how fast the impulse travels along the nerve.

What is an EMG/NCS?

This examination is used to record and view a muscle contraction utilizing specific neurodiagnostic equipment; this data is then transmitted into the computer. The test records the electrical activity associated with muscle contraction. This test is performed to determine if nerves or muscles are diseased or injured. A NCS measures the strength and speed of the electrical impulses of specific muscles

What to Expect

During EMG portion of the test, a very small electrode, the size of a pin) will be inserted through the skin into several muscles. When the electrode is inserted, you will be asked to remain very still and relax the muscle be testing; you will then be asked to contract the muscle being tested.

During the NCS portion of the study, an electrode is placed over a particular muscle and a tiny impulse will be administered to the muscle to test the speed of the electrical impulse through a particular muscle.

Preparation for Test

Wear loose, comfortable clothing and don’t use any lotions or oils. If you take medications, continue to do so unless otherwise advised by the physician.