This test measures the electrical activity of a certain muscle by detecting any indications of slowing down or blocking of responses to nerve stimulation. Results will show information on the muscle tested and reveals how good at receiving stimulation from the nerve.
Purpose of EMG
Result of EMG allows the patient to understand unexplained muscle weakness and paralysis. Thru EMG, doctors could find the cause of pain or numbness in hands or in other areas. Thru this test, the origin of muscle disorder could be identified – either from nerve disorder or from the muscle itself. More information on formigamento nas mãos on neuropatias.com.
Procedure of EMG
An electrode, which is in the form of very fine needle, is inserted thru the skin into the muscle of the patient. Once it is inside, the patient will have to contract his/her muscle slowly, could be by bending the arm. This is done with gradual increase in force while the electrode inside records the activity which is being displayed onscreen.
Nerve Conduction Velocity Test (NCV)
Also known as “nerve conduction study”, this examination shows how electrical impulses move along a nerve. Damaged nerve could be detected since it conducts slower speed signal and strength as compared with healthy nerve.
Purpose of NCV Test
This test allows the doctor to differentiate injury to the nerve fiber from injury to the myelin sheath covering the nerve. This differentiation is very necessary to properly diagnose and treat the patient’s suffering from numbness in hands or any other pain.
Procedure of NCV Test
Flat electrodes are placed on the patient’s skin with regular spacing, just above the nerve that is being tested. Nerve stimulation is done by introducing low intensity electric current. Velocity of impulses are shown onscreen. Damage to myelin sheath is identified if velocity response is slower than normal. Damage to nerve axon is identified if nerve’s response to stimulation by the current is decreased but with a relatively normal speed of conduction.