Higher Diagnostic Yield With the Combined Sensory Index in Mild Carpal Tunnel Syndrome

OBJECTIVES The combined sensory index (CSI), a sensitive composite score of 3 median sensory comparison studies, may still be underutilized in diagnosing mild cases of carpal tunnel syndrome (CTS). Our goal was to compare the effectiveness of the "standard" median digit 2 (D2) sensory study to a CSI algorithm in diagnosing mild CTS. METHODS We retrospectively identified patients with typical CTS symptoms and signs. Electrodiagnostically normal patients and those having mild CTS diagnosed by D2 or CSI algorithm were separated into groups. RESULTS Seventy-four patients were included, and 51 (68.9%) were diagnosed with mild CTS. Of the 51, 31 (60.8%) were diagnosed using the CSI algorithm, and 20 (39.2%) were diagnosed using D2 (P < 0.001). CONCLUSIONS Our data suggest that the CSI algorithm is significantly more effective than the D2 to diagnose mild CTS. If mild CTS is diagnosed earlier, treatment can be initiated sooner and morbidity can likely prevented.