L22: Superficial Back Flashcards
(20 cards)
1
Q
3 groups of back muscles
A
- Superficial back muscles aka axioappendicular muscles
- Intermediate back muscles
- Deep back muscles
2
Q
What is meant by extrinsic back muscles? Which muscle groups does this refer to? What is meant by intrinsic back muscles? Which muscle group does this refer to?
A
- Extrinsic back muscles: These originate from bony structures of back and insert on bones of upper limb, moving the upper limb and not the back. These are the superficial and intermediate back muscles
- Intrinsic back muscles: primary movers of the back. These are the deep back muscles.
3
Q
Name superficial back muscles
A
- Trapezius
- Latissimus dorsi
- Levator scapulae
- Rhomboid major and minor
4
Q
Name intermediate back muscles. Function?
A
- Serratus posterior superior
- Serratus posterior inferior
- Respiration
5
Q
Which rami innervate extrinsic back muscles? Intrinsic back muscles?
A
- Ventral rami innervates extrinsic back muscles
- Dorsal rami innervates intrinsic back muscles
6
Q
Trapezius. O, I, I, A and blood supply
A
- O: occipital bone, ligamentum nuchae, spinous process of C7-T12
- I: clavicle (lat 1/3rd), acromion and spine of scapula
- I: CN XI (motor), C3,4 ventral rami (pain and proprioception)
- A: holds upper limb to trunk, adducts/retracts scapula via middle fibers, depresses scapula via lower fibers, rotates scapula so that inferior angle is moved laterally for adduction of upper limb
- Vascular: superficial branch of transverse cervical artery from thyrocervical trunk (off subclavian)
7
Q
What causes drooping of scapula/shoulder drop?
A
- Injury to CN XI, innervating trapezius
8
Q
Latissimus dorsi. O, I, I, A and blood supply
A
- O: spinous process of lower six T vertebrae, thoracolumbar fascia, iliac crest and lower 3 or 4 ribs
- I: intertubercular groove of humerus bw pec major and teres major
- I: thoracodorsal nerve (C6-8 from brachial plexus)
- A: extends arm, rotates arm medially, used in chopping wood and crawl stroke in swimming, adduct/extends/medially rotates humerus at shoulder joint
- Vascular: thoracodorsal a from subscapular artery, which arises from axillary
9
Q
Inability to raise trunk with upper limbs during climb results from injury to what nerve/muscle?
A
- Injury to thoracodorsal nerve, innervating Latissimus dorsi
10
Q
What is the triangle of auscultation?
A
- Triangular gap bounded by trapezius, latissimus dorsi and medial border of scapula
- Good place to listen for respiratory sounds with stethoscope and sounds are less muffled
11
Q
Levator scapulae. O, I, I, A and blood supply
A
- O: transverse processes of C1-3 or 4
- I: superior angle of scapula and along its upper medial border
- I: dorsal scapular nerve (C5) and 3rd/4th cervical nerves
- A: elevates scapula, rotates scapula to move glenoid cavity and shoulder joint inferiorly
- Vascular: dorsal scapular artery (branch off axillary a) or deep branch off transverse cervical artery (from thyrocervical off subclavian)
12
Q
Rhomboid major and minor. O, I, I, A and blood supply
A
- O: spinous process of C7 and T1-5
- I: medial border of scapula
- I: dorsal scapular nerve (C5) and some fibers from C4
- A: adduct scapula, rotate scapula so glenoid cavity moves inferiorly
- Vascular: dorsal scapular artery (branch off axillary a)
13
Q
What nerve is injured that prevents adduction of the scapula?
A
- Dorsal scapular nerve innervating rhomboid major and minor
14
Q
Serratus posterior superior. O, I, I, A
A
- O: ligamentum nuchae and spinous process of C7 to T3
- I: 2nd to 4th ribs
- I: first three thoracic spinal nerves
- A: elevates ribs
15
Q
Serratus posterior inferior. O, I, I, A
A
- O: T11-L2 spinous processes
- I: last 4 ribs
- I: last 4 thoracic spinal nerves
- A: holds ribs steady when diaphragm moves up
16
Q
If during a surgical procedure, T9-12 nerves are damaged. Which one of the following muscles would be affected? A. Rhomboid major B. Trapezius C. Levator scapulae D. Serratus posterior superior E. Serratus posterior inferior
A
- E
17
Q
During a physical exam you notice that a pt has one shoulder lower than the other. This condition results from damage to what muscle/s? A. Levator scapulae B. Latissimus dorsi C. Serratus anterior D. Trapezius E. A&D
A
- E
18
Q
You notice that a pt is unable to extend his arm at the shoulder joint. You expect nerve damage to the muscle responsible for this action. Which group of nerves might be involved? A. T1-L1 B. C6-8 C. T8-11 D. C1-6
A
- B (thoracodorsal nerve, C6-8 from brachial plexus)
19
Q
Rhomboid major and minor act to do what action to the scapula? A. Rotate B. Adduct C. Depress D. Abduct E. A and B
A
- E
20
Q
What muscles virtually cover the entire length of the back?
A
- Trapezius and latissimus dorsi
