Roc-based validation of palmar sensory latency in Carpal tunnel syndrome diagnosis.

BACKGROUND

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy, and electrophysiological assessment remains the diagnostic gold standard.

OBJECTIVE

This study aimed to determine the diagnostic performance of palmar sensory latency (PSL) in CTS using receiver operating characteristic (ROC) analysis and to examine its association with clinical severity.

METHODS

A total of 136 upper limbs from 98 individuals evaluated for suspected CTS were retrospectively analyzed. Standard motor and sensory nerve conduction studies of the median nerve were performed, and PSL was obtained by stimulating the palm and recording from the index finger. ROC curve analysis was used to establish diagnostic cut-off values, sensitivity, and specificity.

RESULTS

Among the examined limbs, 38 were diagnosed with CTS and 98 were normal. The optimal PSL cut-off was identified as ≥ 1.61 ms, yielding 84.2% sensitivity and 93.8% specificity (AUC = 0.87). PSL also showed a significant correlation with the Boston Carpal Tunnel Questionnaire (BCTQ) functional scores (r = 0.46, p < 0.01).

CONCLUSION

Palmar sensory latency is a highly sensitive and specific electrophysiological parameter for CTS diagnosis. Incorporating PSL into standard nerve conduction protocols may enhance early detection and diagnostic precision in clinical neurophysiology practice.