Skier’s thumb is an acute partial or complete rupture of the ulnar collateral ligament (UCL) of the thumb metacarpophalangeal joint (MCPJ) due to a hyperabduction injury. The injury typically occurs when the thumb is subjected to a strong lateral and backward traction force. The terms “skier’s thumb” and “gamekeeper’s thumb” are often used interchangeably, but skier’s thumb relates to acute trauma, whereas gamekeeper’s thumb refers to a chronic overuse injury.