The tendon of Extensor Pollicis Longus can be seen on the radial side of the wrist, at the base of the thumb where it forms the lower border of the 'anatomical snuffbox' a triangular shape between two tendons.
Origin - Upper posterior surface of the ulna.
Insertion - Base of the distal phalanx of the thumb.
Actions - Extension of the wrist.
Extension of the thumb.
Innervation - Posterior interosseous nerve.
Daily uses - Releasing your grip on an object.
Example Strengthening Exercises - Wrist extension using a dumbbell.
Example Stretches - Wrist extensor stretch.
Related muscles - Flexor Pollicis Longus.