L

ith this curious name, perhaps many have imagined the position that the hand has when grasping a gun and pulling the trigger to shoot.
Well, you are right since that in trigger finger, the finger remains as you are imagining it: in general, when performing a complete flexion of the finger, the metacarpophalangeal joint remains in extension while the proximal and distal interphalangeal joints do manage to do some flexion.

What are the causes of trigger finger?

The cause is tenosynovitis of the tendon sheath of the superficial and deep flexor muscles of the fingers, which when inflamed can affect the tendon and form nodules, which prevents or hinders its passage through this tunnel.
The sheath can also thicken, so its diameter decreases, making it difficult for tendons to pass through it. Many times, when trying to extend the finger, the tendon can become stuck at the entrance to the sheath, and once it gets through the tunnel, a sudden extension of the finger may be experienced.

How does this inflammation occur?

Although the cause of the trigger finger is unknown, it is generally common in people with jobs or activities that involve repetitive flexion-extension of the phalanges, over a prolonged period of time, or in the face of intense external pressure.
It is also more frequent in women, in people with diabetes and rheumatoid arthritis, and in people between the ages of 40 and 60.

What are the symptoms of trigger finger?

In the presence of a trigger finger we can sometimes find:

• A small lump in the palm of the hand.
• Inflammation.
• Pressure or paralysis of the finger joints.
• Pain when flexing the involved finger.

In which cases is the trigger finger more frequent?

This involvement is frequent in both children and adults, however, it occurs mainly in:

• People over 45 years of age.
• Female sex.
• It occurs mostly on the middle and ring fingers. However, on rare occasions, the thumb can also suffer.
• People suffering from diabetes, rheumatoid arthritis.
• People who perform tasks or activities that require a constant and repetitive grip with their hands, such as those people who work a long time on the computer.