superficial back LOs

Question 1

latissimus dorsi

Answer 1

• BL: lower thoracic spinous processes/iliac crest > floor of intertubercular sulcus of humerus
• SC segment: C6-8
• action: adduction/extension/medial rotation of humerus
• innervation: thoracodorsal nerve

Question 2

levator scapulae

Answer 2

• BL: transverse processes C1-C4 > superior angle/superomedial scapula border
• SC segment: C4-C5
• action: elevation/downward rotationof scapula
• innervation: dorsal scapular nerve

Question 3

pectoralis major

Answer 3

• BL: clavicle/sternum > lateral lip of intertubercular sulcus of humerus
• SC segment: C5-C6 (clavicular head), C7-T1 (sternocostal head)
• action: humeral adduction/flexion/medial rotation
  
  • sternocostal portion assists with extension of flexed arm
• innervation: medial and lateral pectoral nerves

Question 4

pectoralis minor

Answer 4

• BL: ribs 3-5 > coracoid process
• SC segment: C5-T1
• action: anterior tilt of scapula, shoulder depression, forced inspiration
• innervation: medial and lateral pectoral nerves

Question 5

rhomboids

Answer 5

• BL: T2-5/C7-T1 > medial scapula border
• SC segment: C4-5
• action: scapular retraction, elevation, downward rotation
• innervation: dorsal scapular nerve

Question 6

serratus anterior

Answer 6

• BL: rib 1-8/10 > costal surface of medial border of scapula
• SC segment: C5-7
• action: scapular protraction, upward rotation
• innervation: long thoracic nerve

Question 7

subclavius

Answer 7

• BL: rib 1 > undersurface of clavicule
• SC segment: C5-6
• action:depression and stabilization of clavicle
• innervation: subclavian nerve

Question 8

trapezius

Answer 8

• BL: external occipital protuberance/cervical and thoracic spinous processes > clavicle/acromion/scapular spine
• SC segment: C3-4
• action: scapular elevation. depression, retraction, upward rotation
• innervation: accessory nerve (CN XI)

Question 9

extrinsic muscles

Answer 9

• superficial to thoracolumbar fascia and intrinsic muscles
• involves in movements of shoulder/pectoral girdle and ribs
• 2 layers:
  
  • superficial: limb movement
  • intermediate: proprioception and respiration
• axioappendicular muscles
• where triangle of auscultation is found

Question 10

intrinsic muscles

Answer 10

• deep to thoracolumbar fascia and extrinsic muscles
• movement/stabilization of vertebral column, maintain posture
• 3 layers:
  
  • superficial
  • intermediate
  • deep

Question 11

extrinsic muscle list

Answer 11

• superficial: axioappendicular/limb movement
  
  • trapezius (crainial nerve innervation)
  • latissimus dorsi, levator scapulae, rhomboids (anterior/ventral rami of spinal nerve)
• intermediate: respiration/proprioception
  
  • serratus posterior superior, serratus posterior inferior (anterior rami of spinal nerve/intercostal nerve in periphery)

Question 12

intrinsic muscles list

Answer 12

• superficial: VC movement/stabilization
  
  • splenius: capitis, cervicis (posterior/dorsal rami of spinal n.)
• intermediate: VC movement/stabilization
  
  • erector spinae: spinalis, longissimus, iliocostalis (dorsal rami)
• deep: VC movement/stabilization
  
  • transverse spinales: semispinalis, multifidus, rotatores (dorsal rami)

Question 13

external occipital protuberance

Answer 13

Question 14

spinous process of 7th cervical vertebra

Answer 14

vertebra prominens

not bifid

Question 15

spine of scapula

Answer 15

Question 16

acromion of scapula

Answer 16

Question 17

medial border of scapula

Answer 17

“vertebral border”

Question 18

inferior angle of scapula

Answer 18

Question 19

spinous processes of thoracic vertebrae

Answer 19

Question 20

iliac crest

Answer 20

Question 21

posterior superior iliac spine

Answer 21

Question 22

areas of skin associated with a single spinal segment/nerve

Answer 22

dermatome