De Quervain's Tenosynovitis affects the tendons on the thumb side of the wrist, commonly after activities that require repetitive thumb and wrist motions such as gardening or racquet sports. The tendons become inflamed, causing pain at the base of the thumb and sometimes into the forearm if left untreated. BioSkin Wrist and Thumb braces are designed to stabilize the joint and alleviate pain with medical-grade compression and supportive straps and stays.