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.
Any swelling of the tendons and/or thickening of the sheaths causes friction. The tendons can no longer easily slide through their sheaths. When this happens, some thumb and wrist motions become more challenging, and any movements cause pain. The pain may extend from the forearm to the thumb base.
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 yard, playing golf or racket sports, or lifting your child — can make it worse.
Common symptoms for de Quervain’s tenosynovitis include:
- Pain on the back of your thumb when you make a fist, grab something, or turn your wrist.
- Numbness in the thumb and index finger.
- Swelling of the wrist.
- Stiffness when moving your thumb or wrist.
- Popping of the wrist tendons.
- Difficulty pinching things with your thumb.