Acute attenuation of the extensor pollicis longus tendon. A case report.

The current understanding of tendon biomechanics indicates that indirect injury to the tendon midsubstance requires the presence of preexisting disease during mechanical overload. This belief has been substantiated by the association of extensor pollicis longus rupture with chronic tenosynovitis caused by repetitive activity, inflammatory conditions such as rheumatoid arthritis, and minimally displaced distal radius fractures. This case of acute, traumatic, intratendinous attenuation of the extensor pollicis longus tendon offers a contradiction to the view that midsubstance tendon failure requires preexisting disease.