The impact of wrist extension provocation on current perception thresholds in patients with carpal tunnel syndrome: a pilot study.

Purpose: To determine whether current perception threshold (CPT) varied between subjects with and without carpal tunnel syndrome (CTS) and whether positioning in wrist extension (reversed Phalen's test) was provocative.

Method: Subjects (n=30) were tested using the Neurometer (Neutron, Inc., Baltimore, MD) at 5, 250, and 2,000 Hz in a rest and reverse Phalen's position.