De Quervain's tenosynovitis is a condition that causes pain associated with the movement of the thumb and wrist. The cause of the pain of de Quervain's is inflammation within a confined area around the base of the thumb.
One of the most common causes of thumb and wrist pain is due to tendonitis. De Quervain’s tenosynovitis is a type of tendonitis that is frequently seen in young mothers. This causes pain on the thumb side of the wrist. The pain is worse with movement of the thumb and wrist at the same time. Opening jars, turning doorknobs, and caring for a young child can be difficult.