Lecture 8

Question 1

What is the function of the trapezius?
Innervation?
Blood?

Answer 1

assists in the rotating of the scapula during abduction of humerus above horizontal

upper fibers elevate
middle fibers adduct
lower fibers depress the scapula

innervates: 
accessory nerve (C3-C4)

blood:
superficial branch of transverse cervical artery

Question 2

What is the function of the latissimus dorsi?
innervation?
blood?

Answer 2

Extends, adducts, and medially rotates the humerus

intervention: 
thoracodorsal nerve (C6-C8)

blood supply:
thoracodorsal artery

Question 3

What is the function of the levator scapulae?
Innervation?
blood?

Answer 3

elevates the scapula

innervation:
dorsal scapular nerve (C3-C4)

blood:
transverse and ascending cervical artery

Question 4

What is the function of the rhomboid major and minor?
innervation?
blood?

Answer 4

adducts and elevates the scapula

innervation:
dorsal scapular nerve (C4-C5)

blood:
deep branch of the transverse cervical artery and the dorsal scapular artery

Question 5

What is the function of the serratus posterior superior?
innervation?
Blood?

Answer 5

elevates ribs 2-4

innervation:
anterior rami of supper thoracic nerves (T2-T5)

blood:
segmental supply by intercostal arteries

Question 6

What is the function of the serratus posterior inferior?
innervation?
blood?

Answer 6

depresses ribs 9-12 and may prevent the lower ribs from elevating when the diaphragm contracts.

innervation:
anterior rami of lower thoracic nerves (T9-T12)

blood:
segmental supply through intercostal arteries

Question 7

What is the thoracolumbar facia?

Answer 7

Deep investing membrane throughout most of the posterior thorax and abdomen.

is continuous with the deep fascia of the neck

consists of three layers: anterior, middle, and posterior

It covers the paravertebral deep muscles of the back

Question 8

What are the splenius muscles? What do they do?
innervation?
blood?

Answer 8

1. splenius capitis
2. splenius cervitis

Function:

bilateral: extend neck
unilateral: laterally flex and rotate spine

innervation:
posterior rami of spinal nerves (cervical)

blood:
Deep cervical and occipital arteries

Question 9

What are the erector spinae muscle groups?
Function?
Innervation?
blood?

Answer 9

spinalis, longissimus, and Iliocostalis

Question 10

What is the function of the spinalis capitis, spinalis cervicis, and spinalis thoracis?
Innervation?
blood?

Answer 10

Bilateral = extend vertebral column and head 
unilateral = laterally flexes the spine

Innervation:
posterior rami of the spinal nerves

blood:
Vertebral, deep cervical, occipital, transverse cervical,
posterior intercostal, subcostal, lumbar and lateral sacral arteries

Question 11

What is the function of the longissimus capitis, cervicis, and thoracis?
innervation?
blood?

Answer 11

Bilateral = extend spine and head 
unilateral = laterally flex the spine

innervation:
posterior rami of spinal nerves

blood:
Vertebral, deep cervical, occipital, transverse cervical,
posterior intercostal, subcostal, lumbar and lateral sacral arteries

Question 12

What is the function of the Iliocostalis muscles?

Innervation and blood supply?

Answer 12

Bilateral = extend spine and head

unilateral = laterally flex the spine

Innervates: posterior rami of the spinal nerves

blood:
Vertebral, deep cervical, occipital,
transverse cervical, posterior intercostal, subcostal, lumbar and lateral sacral arteries

Question 13

What is included in the transversospinalis muscle group?

Answer 13

semispinalis (capitis, cervicis, and thoracis)

multifidus

rotatores (cervicis, thoracis, and lumborum)

Question 14

What is the function of the semispinalis?
Innervation?
blood?

Answer 14

Extends head, cervical, and thoracic regions of the spine.
can rotate spine contralaterally

innervation:
posterior rami of spinal nerves

blood:
the deep cervical artery, posterior intercostal artery, subcostal arteries, and lumbar arteries

Question 15

What is the function of the multifidus?
innervation?
blood supply?

Answer 15

stabilizes the spine

posterior rami of spinal nerves

the deep cervical artery, posterior intercostal artery,
subcostal arteries, lumbar arteries

Question 16

What is the function of the rotatores?
innervation?
blood supply?

Answer 16

stabilizes spine and assist with extension and rotary movements of spine

posterior rami of spinal nerves

the deep cervical artery, posterior intercostal artery,
subcostal arteries, lumbar arteries

Question 17

Function of the interspinales?

Answer 17

aids in extension and rotation of vertebral column

Question 18

Function of the intertransversarii?

Answer 18

helps with lateral flexion (unilateral)

stability (bilateral) of vertebral column.

Question 19

Function of the levatores costarum?

Answer 19

helps elevate ribs (respiratory function) and assists with lateral flexion of vertebral column

Question 20

lymphatic drainage of the back?

Answer 20

Lymph from the back drains mainly into paravertebral and retroperitoneal group of lymph nodes and to segmental regions of the back

e.g. cervical region (posterior cervical nodes), axillary
nodes.

Question 21

What makes up the triangle of auscultation?

Why important?

Answer 21

medial boundary = lateral margin of the trapezius

lateral boundary = medial margin of the scapula

inferior boundary = superior margin of the lat dorsi

Thought, at one time, to be the best place to listen to the lungs

Question 22

What makes up the triangle of petit?

why important?

Answer 22

inferior boundary = the iliac crest

anterior boundary = the external abdominal oblique muscle

posterior = latissimus dorsi

the floor = internal abdominal oblique muscle

petit’s hernia (clinical importance)