OBJECTIVE: Restless legs syndrome, now called Willis-Ekbom Disease (RLS/WED), is 
a sensorimotor-related sleep disorder. Little is known of the effect of RLS/WED 
on motor function. The current study investigated upper limb function in RLS/WED 
patients. We hypothesised that RLS/WED patients exhibit subtle changes in tremor 
amplitude but normal dexterity and movement speed and rhythmicity compared to 
healthy controls.
METHODS: RLS/WED patients (n=17, 59 ± 7 years) with moderate disease and healthy 
controls (n=17, 58 ± 6 years) completed screening tests and five tasks including 
object manipulation, maximal pinch grip, flexion and extension of the index 
finger (tremor assessment), maximal finger tapping (movement speed and 
rhythmicity assessment), and the grooved pegboard test. Force, acceleration, 
and/or first dorsal interosseus EMG were recorded during four of the tasks.
RESULTS: Task performance did not differ between groups. Learning was evident on 
tasks with repeated trials and the magnitude of learning did not differ between 
groups.
CONCLUSIONS: Hand function, tremor, and task learning were unaffected in RLS/WED 
patients. Patients manipulated objects in a normal manner and exhibited normal 
movement speed, rhythmicity, and tremor.
SIGNIFICANCE: Further research is needed to assess other types of movement in 
RLS/WED patients to gain insight into the motor circuitry affected and the 
underlying pathophysiology.