Forearm/hand Flashcards
Anatomy
What’s the difference between the extrinsic and intrinsic muscles of the hand?
Extrinsic - the muscle originates from outside of the hand and inserts in the hand.
Intrinsic - the muscle originates inside the hand and insert in the hand
What are the 8 Carpal bone?
Lateral to medial -
“Some Lovers Try Positions…
That They Cannot Handle”
Scaphoid, Lunate, Triquetrum, Pisiform
Trapezium, Trapezoid, Capitate, Hamate
What are the wrist joints?
Radiocarpal joint Intercarpal joints Metacarpophalangeal Carpometacarpal joint Interphalangeal joints
How many phalanges in the hand?
- 2 phalanges in thumb (distal and proximal)
- 3 phalanges in digit 2-5 (proximal, intermediate, and distal)
What are the fascial compartments of the forearm?
1) interosseous membrane
- Anterior (flexors)
- Posterior
2) Antebrachial fascia - prevents bowstringing
What is the function of the flexor retinaculum (transverse carpal ligament)?
Prevents bowstringing of tendons. The Flexor retinaculum converts the concavity formed by the carpal bones into the carpal tunnel.
What are the contents of the carpal tunnel?
Median Nerve!!!! Flexor digitorum superficialis/profundus, Flexor pollicis longus
What is the palmar aponeurosis
Strong covering of the soft tissue and overlies the long tendons. Contributes to the flexor tendon sheaths distally.
Which four superficial muscles attach to the common flexor tendon (attached to the medial epicondyle of humerus)?
1) Pronator teres
2) Flexor Carpi radialis (FCR)
3) Palmaris longus
4) Flexor carpi ulnaris (FCU) - ulnar nerve !!!
What is the intermediate flexor muscle of the forearm?
Flexor Digitorum Superficialis
What are the deep flexor muscles of the forearm?
1) Flexor Pollicis longus (FPL)
2) Flexor digitorum profundus (FDP) - digit 4-5 ulnar nerve, digit 2-3 ant. Interosseous
3) Pronator quadratus
* * Innervated by anterior interosseus nerve (a branch of the median nerve)
What muscles from the posterior compartment of the forearm originates from the lateral epicondyle ?
1) Extensor Carpi radialis brevis
2) extensor digitorum
3) extensor digiti minimi
4) extensor carpi ulnaris
5) supinator
** all are innervated by the deep branch of the radial nerve
What muscles from the posterior compartment of the forearm originates form the supracondylar ridge of humerus?
1) Brachioradialis
2) Extensor carpi radialis longus
* *innervated by radial nerve
Which 4 muscles from the posterior compartment of the forearm originates from the interosseous membrane and innervated by the posterior interosseous nerve?
Abductor pollicis longus (origin: proximal 1/2 of ulna, radius)
Extensor pollicis brevis (Distal 1/3 posterior radius)
Extensor pollicis longus (Mid 1/3 of posterior ulna)
Extensor indicis (Distal 1/3 posterior ulna)
What are the 3 thenar muscles?
1) Abductor pollicis brevis
2) Flexor pollicis brevis
3) Opponens pollicis
- *origin: flexor retinaculum and tubercles of scaphoid/trapezium
- innervations: recurrent branch of median nerve
What are the 3 hypothenar muscles that are innervated by the deep branch of the ulnar nerve?
1) abductor digiti minimi (from pisiform)
2) flexor digiti minimi brevis (hamate/flexor retinac..)
3) opponens digiti minimi (hamate/flexor retinac..)
what are the interosseous muscles, which are innervated by the deep branch of ulnar nerve?
1) Palmar Interossei (adduct digit 2, 4, 5) P..Ad
2) Dorsal Interossei (abduct digit 2-4) D..Ab
Origin, insertion, innervation, action of the Lumbricals.
Origin: tendons of flexor digitorum profundus
insert: lateral sides of extensor expansions, digits 2-5.
Nerves: Lumbrical 1-2 - branch of median
Lumbrical 3-4 branch of ulnar