SOUAYAH NEUROLOGY CH 1

Question 1

The long thoracic nerve innervates the

Answer 1

serratus anterior

Question 2

Which of the following pathways is used for proprioception of the hindlimb but not for vibration of the hindlimb?

a) dorsal spinocerebellar tract
b) spinocervical tract
c) ventral spinocerebellar tract
d) lateral spinothalamic tract
e) rubrospinal tract

Answer 2

a) dorsal spinocerebellar tract

vibration sensation in forelimbs and hindlimbs transmits its impulses via the dorsal columns and the spinocervical thalamic tract.

Proprioceptive sensations from the forelimbs utilize the dorsal column, while those from the hindlimbs travel with the gracile tract to the level of the dorsal nucleus of Clarke.
- from there they travel with the dorsal spinocerebellar fibers to terminate on the nucleus of Z (small collection of cells in the most rostral part of the nucleus gracilis of the medulla.

page 23

Question 3

the first 30 degrees of abduction of the upper arm from the trunk is performed by the _______ muscle, which is innervated by the ________ nerve.

Answer 3

page 23

supraspinatus muscle
suprascapular nerve

(not the axillary nerve)

Question 4

the musculocutaneous nerve arises from the ____ cord of the brachial plexus, and carries fibers from the roots of _____________.

Answer 4

lateral cord

C5,C6,C7

Question 5

the musculocutaneous nerve supplies both the ________ and ___________ muscles.

Answer 5

biceps and brachialis

Question 6

the _________ nerve innervates the skin from the elbow to the wrist and covers the entire forearm from the dorsal to the ventral midline.

Answer 6

lateral cutaneous nerve

Question 7

the _______ muscle is a forearm supinator, especially if the elbow is flexed at 90 degrees.

Answer 7

biceps

Question 8

what is the most common site of compression of the radial nerve?

Answer 8

spiral groove in the posterior aspect of the humerus

Question 9

the radial nerve arises from the _______ cord of the brachial plexus, and comprises fibers of roots _________ .

Answer 9

posterior cord

C5-C8

Question 10

the dorsal scapular nerve is a pure _____ (motor/sensory) nerve. It supplies the _________ muscles and carries fibers of roots _________.

Answer 10

pure motor
rhomboid muscles
roots: C4 and C5

Question 11

The rhomboids function to: _____ and ______ the medial border of the scapula, antagonizing the __________ _________ muscle.

Answer 11

elevate and adduct the medial border of the scapula.

antagonizing the serratus anterior.

Question 12

to differentiate between a lesion of the upper brachial plexus and one of the lateral cord, the most useful muscle to test is the:

a. teres minor
b. biceps
c. pronator teres
d. flexor carpi radialis
e. abductor pollicis brevis

Answer 12

a. teres minor

The teres minor muscles are innervated by the axillary nerve, which originates from the posterior cord and does not carry any contribution from the lateral cord.

Question 13

the pronator teres, flexor carpi radialis, and abductor pollicis brevis are innervated by the ______ nerve.

Answer 13

median nerve

Question 14

the upper trunk of the brachial plexus is formed by the anterior primary rami of the _____ and ______ cervical roots.

Answer 14

C5 C6

Question 15

the anterior divisions of the upper and middle trunks of the brachial plexus unite to form the ______ cord.

Answer 15

lateral cord

Question 16

to differentiate between a lesion of the lower trunk and one of the medial cord, the most useful muscle to tests is the:

a. flexor pollicis longus
b. abductor pollicis brevis
c. abductor digiti minimi
d. extensor indicis proprius
e. first dorsal interosseous

Answer 16

d. extensor indicis proprius

muscles innervated by the C8 radial nerve receive their innervation via the lower plexus, posterior division of the lower trunk and posterior cord without any contribution from the medial cord.

Question 17

to differentiate between lesions of the middle trunk and those of the posterior cord, the most useful muscle to test is the:

a. triceps
b. pronator teres
c. anconeus
d. extensor digitorum communis
e. extensor indicis proprius

Answer 17

b. pronator teres

the pronator teres is innervated by the C6-C7 median nerve. The lateral cord, provides innervations to the pronator teres without any contribution from the posterior cord.

Question 18

the sciatic nerve is a mixed nerve that carries fibers from ____ to ___ .

Answer 18

L4 - S3

Question 19

the sciatic nerve fibers in the gluteal region are arranged into the medial and lateral trunks. At the proximal popliteal fossa, it divides into the _____ nerve medially, and the _________ nerve laterally. The medial part of the nerve innervates the _________ muscle and the _______ muscles.

Answer 19

tibial nerve medially, peroneal nerve laterally.

adductor magnus and hamstring muscles.

the short head of the biceps femoris is the only thigh muscle supplied by the lateral peroneal division.

Question 20

In Guyon’s canal, the hamate and pisiform bones are sites of compression of the ______ nerve at the wrist.

Answer 20

ulnar nerve

Question 21

the point of entrapment of the median nerve in carpal tunnel syndrome lies under the _____________, which forms the roof of the carpal tunnel.

Answer 21

flexor retinaculum

Question 22

Rarely, radial nerve compression occurs at the level of the ________ process, just _______ [proximal/distal] to the wrist.

Answer 22

styloid, proximal to the wrist

Question 23

The sartorius muscle is a ________ [ flexor/extensor] and ________ [inverter/everter] of the thigh, that is supplied by the _________ nerve.

Answer 23

flexor and everter of the thigh

femoral nerve.

Question 24

the ________ nerve supplies the adductors of the thigh.

Answer 24

obturator nerve

Question 25

The __________________ nerve innervates the gluteus medius and minimus. The ___________ nerve innervates the gluteus maximus.

Answer 25

superior gluteal nerve.

inferior gluteal nerve.