Drumming Performance and Underlying Muscle Activities in a Professional Rock Drummer with Lower-Limb Dystonia: A Case Study

Task-specific focal dystonia (TSFD), characterized by the loss of fine motor control and coordination, affects drummers lower-limb movements, yet it remains relatively understudied, leaving a gap in understanding its effects on drumming performance and underlying muscle activities. This study explores lower limb dystonias impact on drumming performance and underlying muscle activity in a professional rock drummer. The drummer executed an eight-beat pattern on a drum kit, emphasizing kicking the bass drum on the initial beat and performing syncopation of the third beat. Dystonia symptoms primarily manifested in the initial beat, with fewer symptoms on syncopation of the third beat. Analysis revealed decreased bass-drum sound peak amplitude during the initial beat and increased (becoming more negative) synchronization error. Electromyographic (EMG) measurements of ten muscles in the affected right lower limb showed significant changes in the Biceps Femoris (BF), Tibialis Anterior (TA), Extensor Digitorum Longus (EDL), and Extensor Digitorum Brevis (EDB) muscles during symptom onset. Notably, we observed 1) earlier overactivation of the TA and EDL muscles during the leg lift-up motion or preparatory phase of pedaling, 2) reduced activation of the EDB muscle, and 3) increased activation of the BF muscle during the final pedaling movement when symptoms occurred. These findings suggest that lower-limb dystonia symptoms are characterized by a reduction in amplitude and an increase in synchronization error, potentially due to premature overactivation of the ankle dorsiflexor muscles.