Sensory Nerve Conduction Near - Nerve Recording

Near-nerve recording of sensory action potentials evoked by electrical and tactile stimuli is a valuable tool in the assessment of nerve pathophysiology. In most instances where percutaneous recording fails to discriminate sensory potentials from noise they can be picked up by needle recording. To localize the site of focal injuries by determination of conduction across the presumed site of lesion, the use of needle electrodes for stimulation and recording is superior to surface electrode technique. In regenerating nerve fibres, sensory potentials can be recorded with needles several months before they can be obtained with surface electrodes. Correlations between histological findings in sural nerve biopsies with sensory potentials from the same nerve have resulted in valuable information as to the contribution of different nerve fibre diameters to conduction velocity, shape and amplitude of sensory potentials in different types of neuropathies.