UL2 - Muscles of the forearm, wrist & hand

Question 1

list the compartments & layers within each compartment of the forearm - how many muscles in each layer?

Answer 1

anterior compartment - (flexors) has muscles for flexing the wrist and fingers; three layers:
- superficial = 4
- intermediate = 1
- deep = 3

posterior compartment - (extensors) has muscles for extending the wrist & fingers; two layers:
- superficial = 6
- deep = 5

Question 2

forearm - list the muscles of the anterior superficial layer. where do they arise from?

Answer 2

pronstormteres
flexor carpi radialis
palmaris longus
flexor carpi ulnaris

arise from the common flexor tendon at the medial epicondyle of the humerus

Question 3

forearm - list the muscle of the anterior intermediate layer. where does it arise from?

Answer 3

flexor digitorum superficialis

arises from the common flexor tendon at the medial epicondyle

Question 4

forearm - list the muscles of the anterior deep layer

Answer 4

flexor digitorum profundus
flexor pollicis longus
pronator quadratus

Question 5

what muscle groups arise from the common flexor tendon of the forearm?

Answer 5

muscles of the superficial & intermediate layers of the anterior/ flexor forearm compartment (5 muscles total)

Question 6

forearm - list the muscles from the posterior superficial layer (6)

Answer 6

brachioradialis - separates the anterior & posterior compartments
extensor carpi radialis longus
extensor carpi radialis brevis
extensor digitorum
extensor digiti minimi
extensor carpi ulnaris

Question 7

forearm - list the muscles of the posterior deep layer (5)

Answer 7

supinator
extensor indicis
abductor pollicis longus
extensor pollicis longus
extensor pollicis brevis

Question 8

what muscles arise from the common extensor tendon of the forearm?

Answer 8

four muscles from the posterior superficial layer of the forearm
- extensor carpi radialis brevis
- extensor digitorum
- extensor digiti minimi
- extensor carpi ulnaris

Question 9

forearm - what is the general innervation of the anterior compartment of the forearm? what muscles are the exceptions?

Answer 9

general innervation by the median nerve

exceptions:
- flexor carpi ulnaris (superficial layer) = innervated by ulnar nerve
- flexor digitorum profundus (deep layer) = medial half innervated by ulnar nerve, lateral half by median nerve

Question 10

forearm - what is the general innervation of the posterior compartment? are there any exceptions?

Answer 10

radial nerve

no exceptions