trigger thumb - congenital hand differences - Children's Hospital Boston

Trigger thumb refers to a thumb that clicks, catches or "locks" as the tip of the thumb moves from a bent to a straight position. At times, your child's thumb may become "locked" in a flexed position.
How common are trigger thumbs?
No one knows exactly how common this condition is. Researchers estimate that trigger thumbs make up about 2 percent of all hand problems in growing children. While often referred to as "congenital" trigger thumbs, many studies of newborns show that this problem does not appear at the time a child is born.
In about 30 percent of children with trigger thumb, both thumbs are affected.
Trigger Thumb What causes trigger thumbs?
Trigger thumbs occur by chance and are not associated with other hereditary or congenital disorders. They're caused when a fibrous band under which your child's thumb tendon normally glides is too tight. This prevents an easy gliding motion and results in a swollen, inflamed tendon. When the tendon becomes inflamed, it's difficult (or impossible) for your child to fully extend his thumb.
What are the symptoms of a trigger thumb?
Your child will have a flexed, or bent, thumb. Early on, your child will be able to extend the thumb, though often this is accompanied by pain, swelling or a noticeable clicking sound. In the later stages, your child's thumb will remain in a flexed position. Often a bump can felt at the base of the thumb in your child's palm.
For more information about the treating trigger fingers at Boston Children's Hospital visit:
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