--while some sensory issues of the larger, myelinated nerves that subsume the sensory impressions of mechanical touch, vibration, and positional sense may be hinted at through abnormal EMG or nerve conduction studies, problems with the smaller, thinly myelinated or unmyelinated nerves that subsume the sensations of pain and temperature cannot be tested by these studies--such nerves are simply to small to isolate in this way.

For those, qualitative sensory testing, sudomotor reflex axon testing, or skin biopsy, especially, may reveal disorders of small-fiber nerves.