Specifically, it affects the tendons of two muscles called abductor pollicis longus and extensor pollicis brevis. De Quervain tenosynovitis was named after Swiss surgeon Fritz de Quervain.

The adductor longus muscle is a hip abductor muscle located in the inner thigh. This muscle controls the thigh bone’s ability to move inward and from side to side. The muscle originates in the ...