ténosynovite de de Quervain

OBS: The precise cause of de Quervain's tenosynovitis is unknown. It is thought that excessive friction from overuse of the thumb and wrist (excessive and repetitive gripping and grasping actions) may be a factor, leading to thickening of the tissues in the compartment housing the APL and EPB tendons. For example, cases have been described in bricklayers, those who sew, piano players, fly fishermen, and golfers. It has also been hypothesized that the condition in some cases may be associated with acute injury to the involved area (direct blow to the forearm or wrist, falling on the thumb).
OBS: blackberry thumb: Experts caution that practical experience and emerging anecdotal evidence suggest overuse of personal digital assistants (PDAs) ... can conceivably lead to injury of the tendons and accompanying tissue of the thumb. ""Blackberry thumb"" is the latest colloquial interpretation of a very real medical condition called de Quervain's tendonitis, and its variant de Quervain's tenosynovitis. The names refer to inflammation of two tendons that control the opposable digit, or their protective tissue.