 Magnetic resonance imaging (MRI) of the portion of the spine where radiculopathy is suspected may reveal evidence of degenerative change, arthritic disease, or another explanatory lesion responsible for the patient's symptoms.Electrodiagnostic testing, consisting of NCS (nerve conduction study) and EMG (electromyography), is also a powerful diagnostic tool that may show nerve root injury in suspected areas.On nerve conduction studies, the pattern of diminished Compound muscle action potential and normal sensory nerve action potential may be seen given that the lesion is proximal to the posterior root ganglion.