12.2 Musculature of the Forearm Flashcards
Which of the forearm flexors/extenders originate at the medial/lateral epicondyle of the humerus?
Flexors: Medial
Extensors: Lateral
(This is why tennis elbow affects flexors, and golfer’s elbow affects extensors)
What three movements are allowed by the anterior forearm muscles? What three muscles allow this?
Movements: wrist flexion, ulnar/radial deviation
Muscles: palmaris longus, flexor carpi radialis, flexor carpi ulnaris
Insertion of palmaris longus
Palmar aponeurosis
Insertion of flexor carpi radialis
Anterior surface of 2nd and 3rd metacarpals
Insertion of flexor/extensor carpi ulnaris
(how does this relate to movement of the ring finger?)
Anterior/posterior base of fifth metacarpal and medial carpals (which is which?)
This is also why it’s difficult to move the ring finger on its own.
List the three most superficial wrist extensor muscles of the posterior forearm
- Extensor carpi ulnaris
- Extensor carpi radialis brevis
- Extensor carpi radialis longus
Insertion of extensor carpi radialis brevis vs longus
Longus: posterior base of 2nd metacarpal
Brevis: posterior base of 3rd metacarpal
(Flexor carpi ulnaris, on the other hand, inserts at the 2nd and 3rd)
Origin and insertion of pronator quadratus and pronator teres
Quadratus: originates on ant. ulna, and inserts on ant. radius
Teres: Originates on medial supracondylar ridge and proximal ulna, and inserts on lateral radius
Which three muscles flex the digits of the hand?
- Flexor digitorum superficialis
- Flexor digitorum profundus
- Flexor pollicis longus
Describe the insertion of extensor digitorum, extensor digiti minimi, and extensor indicis
Digitorum: flatten out to form extensor hood
Indicis: extensor hood of #2
Digiti minimi: extensor hood of #5
Insertion of extensor pollicis longus/brevis
Longus: distal phalanx of thumb
Brevis: proximal phalanx of thumb
