Hitchhiker thumb

What it means

With the hand relaxed and the thumb in the plane of the palm, the axis of the thumb forms an angle of at least 90 degrees with the long axis of the hand.

The condition known as "hitchhiker's thumb" means, that the distal phalanx of the thumb, when the thumb is extended (as in a "thumbs-up"), can extend backwards toward the nail and outwards at an angle of up to, or more than, 90 degrees from the thumb, whereas normally it will extend straight out with little backward bending.

Rare diseases that can present with this4

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Abducted thumb