Anatomy of the Thumb

(republished with permission from ASSH)

Anatomy 101: Thumb Tendons

(originally published Apr 19,2016 / By The Hand Society)

Did you know that the tendons attached to your thumb run all the way up your forearm? There are four thumb tendons:

• Abductor pollicis longus: This tendon helps you move the thumb away from the palm to form an open hand.
• Flexor pollicis longus: This tendon helps you bend the thumb.
• Extensor pollicis brevis: This tendon travels along the back of the thumb and helps straighten the thumb. It connects the muscle in the back of the forearm to the bone in the middle of the thumb.
• Extensor pollicis longus:  This tendon also travels along the back of the thumb and helps straighten the thumb, but it connects the muscle in the back of the forearm to the bone at the tip of the thumb.

Learn more about anatomy of the fingers, hand, wrist, arm and shoulder at www.HandCare.org.