Test: Dermatome Assessment - C6

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Background/Purpose

A dermatome is an area of skin supplied by sensory neurons that arise from a spinal nerve ganglion. Symptoms that follow a dermatome (e.g. like pain or a rash) may indicate a pathology that involves the related nerve root.
Dermatome assessment involves the clinician performing light touch or pin prick on a area or areas of the skin innervated a particular spinal nerve root. There is some variability in the distribution of nerve segments to different skin surfaces but there is some degree of typical responses.
Since dermatomes assess sensory input (afferrent) for a given nerve root, it may be necessary to also asses the motor (efferent) signals as well.

Procedure

Clinician performs a light touch (light stroke) on the dorsal surface of the proximal phalanx of the thumb. If light touch is indeterminate, it may be helpful to use a pin prick on the medial malleolus. The sensation is graded 0-2 with ‘2’ representing normal sensation, ‘1’ representing impairment, and ‘0’ representing absent sensation. A grade of 0 or 1 represents a failed test.
Performed: Unilaterally

Dialog

Light touch or pin prick dermatome assessment on the dorsal surface of the proximal phalanx of the thumb.

Criteria

• Normal sensation

Measurement

0.00

LOINC Code

0

Scale/Grading

Pass/Fail