What is de Quervain’s tendinosis?

What is de Quervain’s tendinosis?

De Quervain’s tendinosis is a painful swelling (inflammation) of specific tendons of the thumb. The condition is also known as de Quervain tendinitis or de Quervain’s tenosynovitis. DeQuervain’s was named after the Swiss surgeon who first described the condition in 1895.

Tendons are bands of tissue that attach muscles to bones. Usually tendons slide easily through a tunnel of tissue called a sheath. The sheath keeps the tendons in place next to the bones of the thumb. Tendons that easily slide through their sheaths allow the thumb to move without difficulty or pain. The pain may extend from the forearm to the thumb base.

Any swelling of the tendons and/or thickening of the sheaths cause friction. The tendons can no longer easily slide through their sheaths. When this happens, certain thumb and wrist motions become more difficult to do.