Comparison of the finger wrinkling test results to established sensory tests in peripheral nerve injury.

The phenomenon that denervated skin does not wrinkle or shrivel like normal palmar skin after soaking in water was investigated. Forty-one patients with complete or partial peripheral nerve lacerations or traumatic nerve compressions were given a battery of tests to evaluate sensory and motor function. The results from patients' wrinkle tests were compared with the findings from their two-point discrimination and ninhydrin sweat tests. Twenty four patients with recent complete peripheral nerve injuries demonstrated an absence of finger wrinkling, two-point discrimination, and sweating over the cutaneous distribution of the damaged nerve. Nine patients with partial nerve lacerations demonstrated varied results depending upon the amount and location of the nerve injury. Eight patients with nerve compressions continued to wrinkle and sweat even when two-point discrimination was decreased or absent. These findings indicate that only in patients with a recent complete peripheral nerve lesion does an absence of wrinkling always correspond with a loss of other sensory modalities. The presence of wrinkling in a patient with a nerve compression does not correlate with the patient's sensory modalities.