Spry Juncture, LLC
How to Evolve Gracefully
Extensor Pollicis Longus
Region
Origin & Insertion
['Origin: Posterior ulna and interosseous membrane', 'Insertion: Base of distal phalanx of thumb']
Synergistic Muscles
['EPB', 'APL']
Joints
['Thumb joints', 'Wrist']
Primary Actions
['Extends thumb at IP, MCP, and CMC joints']
Nerve & Spinal Segment
Radial nerve (posterior interosseous branch)
Brachial plexus; C7–C8
Interesting
Creates medial border of anatomical snuffbox. [Gray's]
Reversal of Action
Press wrist downward while thumb stays fixed
Common Dysfunctions
Difficulty with thumb retropulsion, snapping tendon over wrist
How to Stretch
Flex thumb and ulnar deviate wrist.
Trigger Points
How to Strengthen
Resisted thumb extension with putty or band.
Concentric Action
Extend thumb at IP joint
Applications:
Used in tip pinch recovery and thumb motion post-fracture
Eccentric Action
Control thumb return from full extension
Isotonic Action
Band extension for thumb
Related Conditions
['Thumb tendonitis', 'Tenosynovitis']
Isometric Action
Maintain extension at IP
Exercise Ideas
['Thumb tip lifts', 'Resisted extension', 'Putty thumb drag']