[Spasm or dimpling of the hypothenar eminence]

Area of Science:

• Neurology
• Musculoskeletal Disorders

Background:

• Hypothenar muscular spasm is a rare condition characterized by involuntary contractions in the muscles of the palm's base.
• Previous reports of this specific syndrome are extremely limited, highlighting its rarity.

Observation:

• A 62-year-old male presented with bilateral hypothenar muscular spasm, described as "dimpling."
• The spasms involved recurrent, arrhythmic contractions of the palmaris brevis muscle.
• Electromyography (EMG) did not reveal signs of denervation.

Findings:

• Infiltration of the ulnar nerve with xylocaine effectively halted the muscle contractions.
• The clinical and electromyographic features resemble those of hemifacial spasm.
• Ulnar nerve compression distal to its division at the wrist is hypothesized as a potential etiology.

Implications:

• This case expands the understanding of rare neuromuscular conditions affecting the hand.
• The findings suggest a potential link between ulnar nerve compression and hypothenar spasms.
• Further investigation into ulnar nerve pathologies may be warranted for similar presentations.