What Are the Side Effects of an EMG Test?

During an Electromyography test, or EMT, patients may experience twinges and spasms from surface electrodes and discomfort or pain from needle electrodes, explains Mayo Clinic. Minor bruising at the insertion site of needle electrodes is possible.

Discomfort caused by needle electrodes should stop shortly after the electrodes are removed and individuals concerned with pain during an EMT should ask their physicians about taking a short break during the procedure, recommends Mayo Clinic. Bruising typically fades after several days. Serious complications from an EMT test are rare, but may include bleeding, infection and nerve injury at the site of needle electrodes. There is a very small risk of lung collapse when needle probes are inserted into the muscles of the chest wall.