QUANTITATIVE ANALYSIS OF EXTRATERRITORIAL MOTOR FUNCTION IN PATIENTS WITH CARPAL TUNNEL SYNDROME

Although extensive research has been conducted on extramedian sensory manifestations observed in carpal tunnel syndrome (CTS) patients, extraterritorial motor dysfunction has received relatively little attention from clinicians. This study aimed to explore extraterritorial motor performance in CTS patients utilizing a gyrosensor. We measured angular velocity signals during rotational movements of the forearm in 37 patients with mild-to-moderate CTS and 42 control subjects. Four quantitative analysis indices were calculated from the gyro sensor data. All patients completed the Boston-Questionnaire, including 11 items from the symptom severity scale (SSS) and 8 items from the functional severity scale (FSS). Motor symptoms (MOTOR) were assessed by calculating mean scores for SSS items 7 (hand weakness) and 11 (hand clumsiness). CTS patients showed significantly lower values in all forearm pronation/supination parameters compared to control subjects (RMS angular velocity and total power of angular velocity, [Formula: see text]; RMS angular displacement, [Formula: see text]; peak power of angular velocity, [Formula: see text]). Moreover, all analysis indices showed significant correlation with FSS scores ([Formula: see text] to −0.420). RMS angular velocity, RMS angular displacement, and total power also showed a negative correlation with MOTOR scores ([Formula: see text] to [Formula: see text]). Our study demonstrated extraterritorial motor impairment in individuals with early-stage CTS, closely associated with functional impairment and motor symptoms, underscoring its potential clinical relevance. Further investigation is warranted to delineate its precise mechanism.