B and SC 1.2

Question 1

What are the extrinsic back muscles concerned with?

Answer 1

Extrinsic muscles of the back are really concerned with movements of the upper limb or of the rib cage and are not true “intrinsic” back muscles

Question 2

What are the intrinsic muscles of the back?

Answer 2

1. trapezius
2. latissimus dorsi
3. levator scapulae
4. rhomboid major and minor
5. Serratus posterior superior and inferior muscles
   - All of these muscles are concerned with movements of the upper limb except the serratus muscles, which move the rib cage

Question 3

What muscles are true intrinsic back muscles?

Answer 3

The erector spinae muscles

Question 4

What is chronic back pain and the common causes?

Answer 4

• The extrinsic muscles can be strained with excessive movements of the neck, upper limbs, or rib cage
• Chronic back pain, most common in the lumbar region, is a major health issue
• The pain may be due to:
  1. disorders of the vertebral ligaments, joints, or intervertebral discs
  2. disorders of the dura mater covering the spinal cord
  3. nerve root compression
  4. or cramping of muscles.

Question 5

What is the origin of the splenius capitis and splenius cervicis muscles?

Answer 5

The splenius capitis and splenius cervicis muscles blend together and arise from the ligamentum nuchae and the spinous processes of the C7-T6 vertebrae (capitis from C7-T3 and cervicis from T3-T6)

Question 6

Where do capitis muscles insert?

Answer 6

Capitis fibers insert into the mastoid process of the temporal bone and the lateral third of the superior nuchal line of the occipital bone

Question 7

Where do cervicis muscles insert?

Answer 7

The cervicis fibers ascend to attach to the transverse processes of the C1-C3 vertebrae and the posterior tubercle of C3

Question 8

What is the action of the splenius capitis and splenius cervicis muscles?

Answer 8

Acting with their opposite partners, the splenius capitis and splenius cervicis extend the head and neck. Acting unilaterally, they laterally bend the head and neck to the side of the contraction.

Question 9

What is the innervation of the capitis?

Answer 9

The capitis is innervated by the posterior rami of the middle cervical spinal nerves

Question 10

What is the innervation of the cervicis?

Answer 10

The cervicis is innervated by the posterior rami of the lower cervical spinal nerves

Question 11

What do the splenius capitis and splenius cervicis muscles form?

Answer 11

The splenius capitis and splenius cervicis form the superficial layer of intrinsic back muscles

Question 12

What are the intrinsic back muscles usually innverated by?

Answer 12

1. Generally, intrinsic back muscles are innervated by posterior rami of spinal nerves. 2. The semispinalis capitis and erector spinae muscles also are deep intrinsic muscles.
2. The teres minor and major muscles and the supraspinatus muscle are scapular muscles associated with movements of the upper limb

Question 13

Can the splenius capitis and splenius cervicis muscles be involved in neck pain?

Answer 13

1. As intrinsic muscles that extend the neck, these muscles can be involved in neck pain
2. This pain may be a result of simple muscle tension, holding one’s neck in an unusual fixed position for a long period of time (when awake or asleep), or hyperextension

Question 14

What can spasm result in?

Answer 14

Spasm (a reflexive cramping) of the muscle may eventually produce ischemia in the muscle, adding to the pain

Question 15

What is the origin of the rhomboid minor muscle?

Answer 15

The rhomboid minor muscle arises from the ligamentum nuchae and the spinous processes of the C7 and T1 vertebrae

Question 16

What is the origin of the rhomboid major muscle?

Answer 16

The rhomboid major muscle arises from the supraspinous ligaments and the spinous processes of the T2-T5 vertebrae

Question 17

Where do the rhomboid major and minor muscle insert?

Answer 17

1. The fibers of these 2 muscles often blend together and attach to the medial border of the scapula from about the level of the spine to the inferior angle
2. The rhomboid minor also attaches to the smooth triangular surface at the medial end of the spine of the scapula

Question 18

What is the action of the rhomboid major and minor muscles?

Answer 18

1. These muscles retract the scapula and rotate it to depress the glenoid cavity
2. They also fix the scapula to the thoracic wall
3. They assist in forcibly lowering the raised upper limb

Question 19

What is the innervation of the rhomboid major and minor muscles?

Answer 19

Dorsal scapular nerve (C4 and C5)

Question 20

What type of the muscles are the rhomboid major and minor muscles?

Answer 20

• The rhomboid minor and rhomboid major muscles are superficial back muscles.
  1. Most superficial back muscles have attachments to the scapula and are involved with movements of the upper limb.
  2. The rhomboid major is about 2 times wider than the rhomboid minor.

Question 21

What can damage to the dorsal scapular nerve cause?

Answer 21

Damage to the dorsal scapular nerve can weaken the rhomboid muscles, resulting in an ipsilateral shift of the scapula as the pull of the other scapular muscles draws the bone toward the shoulder (winged scapula)

Question 22

How would you test the rhomboids?

Answer 22

The rhomboids may be tested clinically by having the patient place the hands posteriorly on the hips and then push the elbows posteriorly against resistance

Question 23

What is the origin of the serratus posterior superior muscle?

Answer 23

The serratus posterior superior muscle attaches to the lower extent of the ligamentum nuchae and the spinous processes of the C7-T3 vertebrae

Question 24

What is the origin of the serratus posterior inferior muscle?

Answer 24

The serratus posterior inferior muscle attaches to the spinous processes of the T11-L2 vertebrae and their supraspinous ligaments

Question 25

Where does the serratus posterior superior/inferior insert?

Answer 25

1. Four fleshy digitations attach the serratus posterior superior to the 2nd to 5th ribs just lateral to their angles. 2. The serratus posterior inferior divides into 4 flat digitations that insert into the inferior borders of the last 4 ribs just lateral to their angles

Question 26

What is the actions of the serratus posterior superior and inferior?

Answer 26

1. The serratus posterior superior elevates the ribs | 2. the serratus posterior inferior pulls the ribs outward and downward, counteracting the inward pull of the diaphragm.

Question 27

What is the innervation of the serratus posterior superior?

Answer 27

the anterior rami of the T1-T4 spinal nerves

Question 28

What is the innervation of the serratus posterior inferior?

Answer 28

the anterior rami of the T9-T12 spinal nerves

Question 29

What type of muscles are the serratus posterior superior/inferior?

Answer 29

These 2 muscles have attachments to the ribs, are considered muscles of the thoracic wall (can be lumped into extrinsic back muscles), and act on the ribs during respiration

Question 30

Are the serratus posterior superior/inferior ever fused?

Answer 30

These 2 muscles are often thin and may be fused to overlying musculature

Question 31

When is the serratus posterior superior/inferior well developed?

Answer 31

- These 2 sets of muscles are accessory muscles of respiration and may be well developed in athletes. - In the elderly, however, they are often thin and even difficult to discern - Rarely, the serratus posterior inferior may be entirely absent

Question 32

What is the origin of the semispinalis capitis muscle?

Answer 32

arises by a series of tendons from the transverse processes of the first 6 or 7 thoracic vertebrae and the lower cervical vertebra

Question 33

What is the insertion of the semispinalis capitis muscle?

Answer 33

This broad muscle inserts between the superior and inferior nuchal lines of the occipital bone

Question 34

What is the action of the semispinalis capitis muscle?

Answer 34

Extends the head and cervical spine, and rotates the head so that the face turns toward the opposite side

Question 35

What is the innervation of the semispinalis capitis muscle?

Answer 35

Posterior rami of cervical spinal nerves

Question 36

What group is the semispinalis capitis muscle part of?

Answer 36

1. The semispinalis capitis is 1 of 3 groups of semispinalis muscles 2. The other 2 are the cervicis and thoracis groups. 3. The semispinalis capitis muscle covers the semispinalis cervicis muscle

Question 37

What are subocciptal muscles innervated by?

Answer 37

by the suboccipital nerve (C1 posterior ramus)

Question 38

What are the semispinalis musicales part of?

Answer 38

1. The semispinalis muscles (capitis, cervicis, and thoracis components) are part of the transversospinal muscle group, which is situated deep to the erector spinae and fills the concave region between the transverse and spinous processes of the vertebrae. 2. This group of muscles sometimes is referred to clinically as the paravertebral muscles

Question 39

When can the deep intrinsic muscles of the neck be strained?

Answer 39

These deep intrinsic muscles of the neck may become strained with excessive movements of the neck or when the neck is kept fixed in one position for a long time

Question 40

What does the erector spinae muscle consist of?

Answer 40

1. iliocostalis 2. longissimus 3. spinalis muscle

Question 41

Where do the rejector spinal muscles arise from?

Answer 41

- They arise by a broad tendon (deep to the thoracolumbar fascia) from 1. the posterior aspect of the iliac crest, 2. the posterior aspect of the sacru 3. the sacral and inferior lumbar spinous processes 4. The supraspinous ligament.

Question 42

Where does the iliocstalis muscles attach?

Answer 42

The iliocostalis muscles attach to the angles of lower ribs and the cervical transverse processes

Question 43

Where does the longissimus muscle insert?

Answer 43

The longissimus muscles attach to the ribs between the tubercles and angles, to the transverse processes in the thoracic and cervical vertebral regions, and to the mastoid process of the temporal bone

Question 44

Where does the spinalis muscle insert?

Answer 44

The spinalis muscles attach to the spinous processes in the upper thoracic region and midcervical region and to the skull

Question 45

What is the action of these erector spinea muscle?

Answer 45

1. Together, these muscles extend the vertebral column and head 2. Unilaterally, they bend the vertebral column laterally 3. Specifically, the erector spinae are powerful extensors of the thoracic and lumbar spine 4. Their action on the cervical spine is weak and overshadowed by the actions of the semispinalis and splenius muscles

Question 46

What is the innervation fo these erector spinea muscles?

Answer 46

Posterior rami of the respective spinal nerves in each region

Question 47

What is the iliocostalis muscles classified into?

Answer 47

Because of their locations, the iliocostalis muscles are classified into lumborum, thoracis, and cervicis groups

Question 48

What is the longissimus muscle classified into?

Answer 48

the longissimus muscles into thoracis, cervicis, and capitis groups

Question 49

What is the spinals muscles classified into?

Answer 49

spinalis muscles into thoracis, cervicis, and capitis groups

Question 50

When can these erector spinae muscles come into harm?

Answer 50

These strong extensors of the spine can come under extreme stress when one is lifting heavy objects, especially when one lifts with the back instead of keeping the spine straight and lifting with the powerful leg muscles

Question 51

What does the deepest layer of back muscles includes?

Answer 51

Transversospinal (or pasraverteral) muscles

Question 52

What do the trasnverspinal muscles include?

Answer 52

- semispinalis - multifidi - rotatores 1. Most of these muscles arise from the transverse processes of adjacent vertebrae 2. They pass superiorly to attach to spinous or transverse processes of vertebrae above.

Question 53

What are the transverospinal muscles important for?

Answer 53

stabilizing the vertebrae during movements of the vertebral column, and they can assist in extension and rotary movements of the vertebrae

Question 54

What are the transverospinal muscles innervated by?

Answer 54

All are innervated by posterior rami of the respective spinal nerves in each region

Question 55

What are trasnverospinal muscles referred to?

Answer 55

Clinicians often refer to the transversospinal muscles simply as the paravertebral muscles because they form a solid mass of muscle tissue interposed between the transverse and spinous processes

Question 56

What is myofascial back pain?

Answer 56

- a syndrome that is common but poorly understood 1. involves localized musculoskeletal pain (deep aching or burning pain) associated with specific trigger points 2. usually over the erector spinae muscles that maintain posture, especially in the neck and lower back

Question 57

What does the suboccipital region comprises of?

Answer 57

muscles in the deep, posterior aspect of the neck, and these muscles are associated with the atlas and axis (C1 and C2 vertebrae)

Question 58

What type of muscles are these?

Answer 58

argely postural, but they also assist with head movements

Question 59

What are the muscles of the sub occipital region innervated by?

Answer 59

The muscles of the suboccipital region are innervated by the posterior ramus of C1, the suboccipital nerve

Question 60

What nerves are found in the sub occipital region?

Answer 60

The first 3 pairs of cervical spinal nerves (posterior rami)

Question 61

Why is there sub occipital nerve peculiar?

Answer 61

the suboccipital nerve (posterior ramus of C1) does not possess cutaneous sensory nerve fibers, so dermatome charts showing the back and top of the head begin with C2, rather than depicting a C1 dermatome

Question 62

What does the sub occipital nerve have?

Answer 62

possess proprioceptive (position sense) fibers in addition to its somatic efferents and postganglionic sympathetic fibers

Question 63

Why is atherosclerosis dangerous?

Answer 63

The vertebral arteries supply blood to the brain, along with the internal carotid arteries, and atherosclerosis of these arteries can compromise the blood supply to the brain