Children's Hospital Colorado

Trigger Finger/Thumb

What is a trigger finger/thumb?

A trigger finger or thumb happens when trying to bend or straighten the finger or thumb. It locks or catches and does not move freely. In children, it is often first seen when the child is older than 1 year of age.

What causes a trigger finger/thumb?

A trigger finger/thumb happens because the sheath (tunnel of tissue that the tendon moves through) isn't wide enough or gets swollen. The tendon can't glide smoothly and gets stuck. Over time, this may also cause a small bump to form at the base of the finger/thumb where it meets the palm of the hand. This usually isn't painful.

An artist's rendering of trigger thumb. The left side has a circle with a picture of a joint and tendon inside and the description below it says "The sheath is too tight causing a nodule (small bump) on the tendon. The dotted line shows where the sheath is cut, allowing the tendon to move freely." The right side is a picture of a hand with the bones and tendon shown inside the thumb and the description above it says "The thumb is unable to move freely due to the tendon not being able to move freely through the sheath."

Get to know our pediatric experts.

Sarah Sibbel, MD

Sarah Sibbel, MD

Orthopaedic Surgery

Cailin Brazeau, PA-C

Cailin Brazeau, PA-C

Physician Assistant