De Quervain's tenosynovitis is a painful condition affecting the tendons on the thumb side of your wrist. If you have de Quervain's tenosynovitis, it will probably hurt when you turn your wrist, grasp anything or make a fist. Although the exact cause of de Quervain's tenosynovitis isn't known, any activity that relies on repetitive hand or wrist movement — such as working in the garden, playing golf or racket sports, or lifting your baby — can make it worse. Immobilizing the thumb and wrist with help of a wrist brace or splint can help rest the tendons, increasing healing.
