Trigger finger / thumb (tendovaginitis stenosans)

What is tendovaginitis stenosans – or trigger finger?

With this condition, whenever an affected individual tries to extend a finger or their thumb, the digit frequently suddenly "snaps back". After creating an initial hook, the finger then suddenly snaps back into the extended position. In many cases, however, there is no snapping and the affected individual simply experiences marked pain on forming a fist or gripping something.

Anatomical background to the condition:

On the fingers and on the thumb there are small rings, through which the flexor tendons run. These are called the ring ligaments.
If these tunnel-like structures become too narrow, the flexor tendons are unable to glide along freely inside them. This results in extremely painful and irritating blocking which is reversed in a jerking manner with effort (snapping or triggering of the finger).

How does this condition develop?

Often, patients report that the snapping follows an unusual, strenuous activity (such as gardening, carrying for long periods of time). During these – often unfamiliar – activities, pressure is exerted on the flexor tendons of the fingers and the tendon sheaths become thicker.

Treatment options:

1. Protection and local cortisone treatment (injections)
2. Surgery (ring ligament release), mostly done under local anaesthetic