Spry Juncture, LLC
How to Evolve Gracefully
Flexor Digitorum Profundus
Region
Origin & Insertion
['Origin: Anteromedial surface of ulna and interosseous membrane', 'Insertion: Base of distal phalanges of fingers 2–5']
Synergistic Muscles
['Flexor digitorum superficialis', 'Lumbricals']
Joints
['Wrist', 'MCP', 'PIP', 'DIP joints of fingers 2–5']
Primary Actions
['Flexes distal interphalangeal joints (DIP) of fingers 2–5']
Nerve & Spinal Segment
Median nerve (lateral part) and ulnar nerve (medial part)
Brachial plexus; C8–T1
Interesting
Only muscle that flexes the DIP joints. [Gray's Anatomy]
Reversal of Action
Draw palm toward fingers (used in claw release drills)
Common Dysfunctions
Difficulty with grip, claw hand deformity
How to Stretch
Extend fingers fully with wrist extended.
Trigger Points
How to Strengthen
Grip tools, putty, or towel squeeze.
Concentric Action
Flex DIP joints of fingers
Applications:
Essential in hand rehab and tendon gliding recovery
Eccentric Action
Slowly extend fingers from tight fist
Isotonic Action
Theraputty gripping, squeeze ball
Related Conditions
['Claw hand', 'Flexor tendon injury']
Isometric Action
Hold fingers in mid-flexion under resistance
Exercise Ideas
['Putty rolls', 'Fingertip holds', 'Reverse curls']