Medical Definition of Thorough-pin
1.
A disease of the hock (sometimes of the knee) of a horse, caused by inflammation of the synovial membrane and a consequent excessive secretion of the synovial fluid.
This is probably so called because there is synovial distention of the sheath of the flexor perforans tendon producing an oval swelling on each side of the leg, appearing somewhat as if a pin had been thrust through.
Source: Websters Dictionary
(21 Jun 2000)
Lexicographical Neighbors of Thorough-pin
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