Reaction time and movement time in patients with carpal tunnel syndrome: an electromyographic study

Objective. To measure the motor performance of the flexor pollicis brevis, first dorsal interosseus, and flexor pollicis longus muscles using the parameters electromyographic muscle reaction time and movement time in patients with carpal tunnel syndrome during key turning function. Method. A total of 37 female patients with right hand pain were divided into two groups: 21 with an electrophysiologically confirmed diagnosis of carpal tunnel syndrome (Group I), and 16 with normal electrophysiological findings (Group II). The reaction time and movement time values obtained by surface electromyography of the right flexor pollicis brevis, first dorsal interosseus, and flexor pollicis longus muscles were compared between groups. Results. Of the 21 patients in Group I, 15 had mild, four moderate, and two severe median nerve lesions. No significant difference between groups was found in the electromyographic reaction time and movement time values of the right flexor pollicis brevis, first dorsal interosseus, and flexor pollicis longus muscles during key turning (P>0.05). There was also no significant difference in electromyographic reaction time and movement time between six patients with severe or moderate carpal tunnel syndrome and 15 patients with mild carpal tunnel syndrome in Group I (P>0.05). Sixteen patients in Group II did not have carpal tunnel syndrome. Conclusion. The results indicate that patients with and without carpal tunnel syndrome have similar values of reaction time and movement time of the flexor pollicis brevis, first dorsal interosseus, and flexor pollicis longus muscles during the pinch grasp function of the hand.