Primary Cueing Tremor: A Task-Specific Tremor of Billiard Players

Area of Science:

• Neurology
• Movement Disorders
• Sports Medicine

Background:

• Task-specific movement disorders (TSMDs) affect highly learned activities.
• While task-specific dystonia in billiards players is documented, task-specific tremor (TST) has not been characterized.
• Billiards involves complex, learned motor sequences susceptible to TSMDs.

Observation:

• Two professional billiards players presented with tremor exclusively during cueing actions.
• Case 1: Right-arm tremor during cue positioning, resolving upon shooting, alcohol-responsive, 6.3 Hz.
• Case 2: Left-hand tremor during bridge formation, unresponsive to medication, improved with deep brain stimulation.

Findings:

• The observed tremor in both cases was task-specific to billiards playing.
• Electrophysiology and alcohol responsiveness suggest a variant of essential tremor.
• Neither patient exhibited features of dystonia, differentiating this from previously reported billiards-related movement disorders.

Implications:

• This study expands the understanding of TSMDs in billiards to include tremor.
• Recognition of primary cueing tremor is crucial for accurate diagnosis and tailored treatment.
• Further research into the pathophysiology and natural history of cueing tremor is warranted.