Snapping thumb: a rare case of stenosing tenosynovitis of the extensor pollicis longus tendon.

Tenosynovitis of the extensor pollicis longus (EPL) is rarely reported in patients without rheumatoid arthritis but may lead to thumb snapping as a consequence of EPL stenosing tenosynovitis.This case presents painful thumb snapping that developed after a wrist trauma and repetitive loading. Ultrasound and MRI were used as diagnostic tools, before surgical release of the EPL in the third extensor compartment was performed. Neither EPL tenosynovitis nor thumb snapping were found at follow-up.