Gamekeeper's Thumb

From Wikipedia:

Gamekeeper's thumb is a type of injury to the ulnar collateral ligament (UCL) of the thumb... This condition is commonly observed among gamekeepers and Scottish fowl hunters, as well as athletes. It also occurs among ordinary people who sustain a fall onto an outstretched hand.

...CS Campbell, an orthopedic surgeon, originally coined the term gamekeeper's thumb in 1955, after he observed this condition in a series of 24 Scottish gamekeepers.The injury appeared to occur as a result of the particular manner in which they killed small animals such as rabbits; the animals were placed on the ground, and their necks were broken as the gamekeeper exerted downward pressure with the thumb and index finger. This maneuver would place a valgus force upon the abducted metacarpophalangeal (MCP) joint. Over time, this would lead to insufficiency of the ulnar collateral ligament (UCL) of the thumb.

Others have noted that Scottish fowl or game hunters would develop this type of injury after carrying their game home in a leather thong, which they would attach to their thumb and drape over their shoulder.

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