Musculoskeletal anatomy: Extrinsic muscle of the back

Question 1

What the muscles of the first layer of the extrinc muscles of the back?

Answer 1

Trapezius and latissimus dorsi

Question 2

What is trapezius origin and insertion?

Answer 2

O: external occipital protuberance, ligamentum nuchae and sp of CVII-TXII \ I: spine of the scapula, acromion, lateral 1/3 of the clavicle.

Question 3

What is the trapezius’ function at the level of the neck and back?

Answer 3

The trapezius contributes to bilateral extension, ipsilateral lateral flexion and contralateral rotation of the neck.

Question 4

What is the trapezius function at the level of the upper limb?

Answer 4

The upper fibers: elevation of the scapula; the middle fibers: retraction and downward rotation; the lower fibers; depression of the scapula and upper ward rotation of the scapula.

Question 5

What is the innervation and blood supply to the trapezius?

Answer 5

Inn: CN XII (spinal accessory nerve); BS: traverse cervical a.

Question 6

What is the origin and insertion of latissimus dorsi?

Answer 6

O: SPs of TVII-LV, sacrum, iliac crest, tharocolumbar apponeurosis | I: the floor of the intertubercular grove of the humerous.

Question 7

What is the function of the latissimus dorsi at the level of the back?

Answer 7

In contributes to bilateral lumbar extention and ipsilateral lumbar flexion.

Question 8

What is the function of the latissimus dorsi at the level of the upper limb?

Answer 8

It provides extension, adduction and midial rotation of the glenohumeral joint.

Question 9

What is the innervation and blood supply of the latissimus dorsi?

Answer 9

Tharocodorsal n. and a.

Question 10

What are the muscles of the second layer of the extrinsic muscles of the back?

Answer 10

Levator scapula and rhomboids major and minor.

Question 11

What is the origin and insertion point of levator scapula?

Answer 11

O: TPs of CI-CIV | I: superomedial border of the scapula.

Question 12

What is the function of the scapula at the level of the back with fixed scapulae?

Answer 12

unilateral ipsilateral lateral flexion and bilateral extension.

Question 13

What is the function of the levator scapula at the level of the upper limb?

Answer 13

Elevation and downward rotation of the scapula.

Question 14

What is the in the innervation to levator scapula?

Answer 14

Dorsoscapular n.

Question 15

What is the origin and insertion of rhomboids major and minor?

Answer 15

O: SPs of CVII to TV | I: Medial border of the scapula.

Question 16

Which rhomboids is above the other?

Answer 16

The minor is superior to the major.

Question 17

What is the function of the rhomboids?

Answer 17

Retraction, slight elevation and downward rotation of the scapula.

Question 18

What is the innervation to the rhomboids?

Answer 18

Dorsoscapular n.

Question 19

What are the muscles of the third layer of the extrinc muscles of the back?

Answer 19

Serratus posterior superior and inferior.

Question 20

What is the function of serratus posterior superior/inferior?

Answer 20

Superior = elevation of the ribs | Inferior = depression of the ribs

Question 21

Where does serratus posterior superior originate and insert?

Answer 21

O: SPs CVII to TIII | I: Ribs 1 to 4

Question 22

Where does serratus posterior inferior originate and insert?

Answer 22

O: SPs TXI to LII | I: Ribs 9 to 12

Question 23

What is the innervation to serratus posterior superior and inferior?

Answer 23

Superior = anterior rami C1 to C4 | Inferior = anterior rami of C9 to C12