Muscle Origins and Actions Quiz

Muscle Origins, Insertions, and Actions

• Pronator Teres: Originates at the coronoid process and medial epicondyle of the humerus; inserts at the middle of the lateral surface of the radius; action: pronates and flexes the arm at the elbow.
• Flexor Carpi Radialis: Originates at the medial epicondyle of the humerus; inserts at the base of the second metacarpal; action: flexes the hand and abducts it.
• Palmaris Longus: Originates at the medial epicondyle of the humerus; inserts at the flexor retinaculum; action: flexes the hand and tenses the palmar aponeurosis.
• Flexor Carpi Ulnaris: Originates at the medial epicondyle; inserts at the pisiform/hook of hamate, 5th metacarpal; action: flexes and adducts the hand.
• Flexor Digitorum Superficialis: Originates at the medial epicondyle; inserts at the shafts of the middle four phalanges of medial four digits; action: flexes middle phalanges at proximal interphalangeal joints, also flexes proximal phalanges at metacarpophalangeal joints.
• Flexor Digitorum Profundus: Originates at the proximal ¼ of medial and anterior ulna and interosseus membrane; inserts at the bases of distal phalanges of 4th/5th digits; action: flexes distal phalanges.
• Flexor Policies Longus: Originates at anterior surface of radius and interosseus membrane; inserts at base of distal phalanx of thumb; action: flexes thumb.
• Brachioradialis: Originates at proximal ¼ of lateral supracondylar ridge of the humerus; inserts at lateral surface of distal end of radius proximal to styloid; action: elbow flexion to neutral position.
• Extensor Carpi Radialis Longus: Originates at lateral supracondylar ridge of humerus; inserts at dorsal aspect of base of 2nd metacarpal; action: extends and abducts hand.
• Extensor Carpi Radialis Brevis: Originates at lateral supracondylar ridge of humerus; inserts at dorsal aspect of base of 3rd metacarpal; action: extends and abducts hand.
• Extensor Carpi Ulnaris: Originates at lateral epicondyle of humerus; inserts at dorsal aspect of base of the 5th metacarpal; action: extends and adducts hand.
• Extensor Digitorum: Originates at lateral epicondyle; inserts at the extensor expansion of medial 4 digits; action: extends medial 4 digits.
• Extensor Digiti Minimi: Originates at lateral epicondyle of humerus; inserts at the extensor expansion of the 5th digit; action; extends pinky.
• Supinator: Originates at lateral condyle of humerus and lateral side of the radius; inserts at lateral surface of proximal 3rd of the radius; action: supinates forearm.
• Extensor Policies Longus: Originates at posterior surface of the middle third of the ulna and interosseous membrane; inserts at dorsal aspect of distal phalanx of the thumb; action: extends thumb.
• Extensor Policies Brevis: Originates at posterior surface of the distal 3rd of the radius; inserts at dorsal aspect of proximal phalanx of the thumb; action: extends thumb.
• Extensor Indices: Originates at posterior surface of the distal 3rd of the ulna and interosseous membrane; inserts at extensor expansion of second digit; action: extends pointer finger.