Trigger thumb / finger

Trigger thumb / finger

A trigger finger or trigger thumb occurs when the tendons that flex the finger enlarge and aren’t able to slide smoothly within the tunnel the tendons pass through. This causes your child’s finger or thumb to pop or click when he/she tries to straighten it.

Although it can affect the child's ability to straighten their thumb, it is rarely painful, does not cause any problems with using their hands and usually gets better without treatment.

In children, the most common digit involved is the thumb. Trigger thumb occurs in approximately three out of 1,000 children at 1 year of age.

Causes

In children, trigger finger and thumb are not caused by an injury or other medical issues. The condition occurs when the tendons that move the finger and thumb enlarge and don’t slide smoothly through the tendon sheath (or tunnel) when the finger is moved.

Although it’s rarely noticed at birth, trigger finger and thumb can be present in infancy. The condition is also often found in older children between the ages of 1 and 4.

Some common signs of trigger finger and thumb include:

• Stiffness in the affected finger or thumb

• A finger or thumb that gets stuck in either a bent or straight position

Treatment

Trigger thumbs in children can resolve spontaneously with no treatment although this can take anything from 1-2 years. There is no evidence that splintage or exercise make any difference to this.

In a small number of children for who it does not get better then surgical release can be carried out to release the tendon from the tendon sheath where it is catching, allowing the tendon to glide more smoothly.

We would not do this under the age of 3 years as the risks of injury to digital nerve causing painful neuroma and loss of sensation are slightly higher before that age.