De Quervain's tenosynovitis, also known as thumb tendonitis or De Quervain's tendinosis, is a painful condition that causes inflammation in the tendons and tendon sheaths at the base of the thumb.  These tendons are situated at the thumb side of the wrist overlying the bony bit of the radius bone. It is very tender and there is usually swelling at this site. The pain can be elicited  by the patient gripping his/her thumb into the palm using the fingers of the same hand, and then twisting the hand towards the little finger side. It sometimes starts after a lot of activity such as gardening or decorating, more than the hand is used  to doing.

Initial treatment involves an injection of steroid around the tendons under a local anaesthetic. This cures the condition in 3 out of 4 cases.  All patients should be careful not to do too much of a particular activity at one time.

If a steroid injection is not effective then a straightforward operation will give permanent relief in nearly all patients. Under a local anaesthetic a small incision is made at the wrist and divides the cover of the tendons. The wound is closed with a dissolving  stitch under the skin. Recovery is quite short.