Spry Juncture, LLC
How to Evolve Gracefully
Abductor Pollicis Brevis
Region
Origin & Insertion
['Origin: Flexor retinaculum and scaphoid/trapezium', 'Insertion: Lateral base of proximal phalanx of thumb']
Synergistic Muscles
['APL', 'Opponens pollicis']
Joints
['Thumb CMC, MCP']
Primary Actions
['Abducts thumb at MCP and CMC joints']
Nerve & Spinal Segment
Median nerve (recurrent branch)
Brachial plexus; C8–T1
Interesting
Prominent in opposition and grasp. [Gray’s Anatomy]
Reversal of Action
Press palm toward thumb in cueing drills
Common Dysfunctions
Loss of thumb abduction strength, early sign of carpal tunnel syndrome
How to Stretch
Pull thumb into adduction gently.
Trigger Points
How to Strengthen
Isometric and active abduction resistance.
Concentric Action
Lift thumb away from palm (perpendicular)
Applications:
Rehabilitates precision grip and improves grasp strength
Eccentric Action
Control return from thumb abduction
Isotonic Action
Thumb lifts off flat surface (paper lift test)
Related Conditions
['Carpal tunnel', 'Thumb arthritis']
Isometric Action
Sustain thumb lifted position
Exercise Ideas
['Thumb lifts', 'Opposition rolling', 'Putty thumb press']