Muscles of Back and Vertebral Column

Question 1

Regions of Vertebral Column

Answer 1

1. Cervical (7)
2. Thoracic (12)
3. Lumbar (5)
4. Sacral (5)
5. Coccygeal (4)

Question 2

Functions of Vertebral Column

Answer 2

1. Support body weight
2. Posture and Locomotion
3. rigid/flexible body axis
4. protect spinal cord and spinal nerves

Question 3

Numbers of each of spinal nerves

Answer 3

8 cervical

12 thoracic

5 lumbar

5 sacral

1 coccygeal

Question 4

Where do spinal nerves arise from?

Answer 4

Ventral and Dorsal Roots

Question 5

Ventral Root Function

Answer 5

convey motor (efferent) fibers FROM spinal cord

Question 6

Dorsal Root Function

Answer 6

convey afferent (sensory) fibers TO spinal cord

Question 7

Spinal nerve precursor and post-cursor

Answer 7

1. Dorsal/ventral root
2. spinal nerve
3. dorsal/ventral rami

Question 8

Innervations of dorsal ramus

Answer 8

1) true back muscles
2) synovial joints of vertebral column
3) overlying skin

Question 9

Innervations of Ventral ramus

Answer 9

upper and lower extremities of anterio-lateral body wall

Question 10

Curvatures of Vertebral Column

Answer 10

1. Cervical
2. Thoracic
3. Lumbar
4. Sacral

Question 11

Primary curvatures

Answer 11

1) Thoracic
2) Sacral
* curves are in same direction as fetal column

Question 12

Reason for primary curvature direction

Answer 12

difference between posterior and anterior parts of vertebrate

Question 13

Secondary curvatures

Answer 13

1) Cervical
2) Lumbar
* curve is opposite to direction in fetal column

Question 14

How Cervical curvature arises

Answer 14

when infant holds its head erect

Question 15

How Lumbar curvature arises

Answer 15

when infant begins to walk

Question 16

Reason for secondary curvature direction

Answer 16

height difference between posterior and anterior intervertebral discs

Question 17

Kyphosis

Answer 17

accentuated thoracic curvature

Question 18

Lordosis

Answer 18

accentuated Lumbar curvature

Question 19

Scoliosis

Answer 19

• Lateral curvature
• rotation of vertebrae

Question 20

Joints of vertebral column

Answer 20

1. intervertebral discs
2. facet (zygapophysial) joints

Question 21

IV Discs characteristics

Answer 21

• cartilaginous
• designed for weight bearing and strength

Question 22

Anatomy of intervertebral disc

Answer 22

• Annulus fibrosus - inner conentric fibrocartilage layers adhering to vertebral bodies
• Nucleus Pulposus - outer shock absorber; high water content
• water content subject to pressure applies

Question 23

Function of facet joints

Answer 23

• small amount gliding between adjacent vertebrae
• collectively large amount motion

Question 24

Things that influence movements of vertebral column

Answer 24

1. tension of joint
2. IV disc compressibility
3. resistance of surrounding muscles/ligaments
4. shape/orientation of facet joints

Question 25

Ligaments of vertebral column

Answer 25

1. Ligamentum flavum 2. Supraspinous ligament 3. Interspinous ligament 4. Intertransverse ligament 5. Anterior longitudinal ligament 6. Posterior longitudinal ligament

Question 26

Anterior longitudinal ligament

Answer 26

* unites anterior surfaces of vertebral bodies * **prevents hyperextension**

Question 27

Posterior longitudinal ligament

Answer 27

* unites posterior surface of vertebral body * located on **inside** of vertebral canal

Question 28

Supraspinous ligament

Answer 28

connects spinous process from **sacrum** to C7

Question 29

Ligamentum Nuchae

Answer 29

* neck ligament * attachment for **cervical muslces**

Question 30

Interspinous ligament

Answer 30

join adjacent spinous processes

Question 31

Intertransverse Ligament

Answer 31

join adjacent transverse processes

Question 32

Ligamentum Flavum

Answer 32

* join adjacent **lamina** of vertebrae * **prevent hyperflexion**

Question 33

Superficial back muscles

Answer 33

1. Trapezius 2. Latissimus Dorsi 3. Levator Scapulae ![]()

Question 34

Latissimus Dorsi

Answer 34

**Origin:** Spinous process of 6 thoracic vertebrae, throacolumbar fascia, iliac crest **Insertion:** intertubercular sulcus of humerus Action: extends, adducts, medially rotates humerus Innervation: thoracodorsal nerve

Question 35

Trapezius

Answer 35

**Origin:** External occipital protuberance, nuchal ligament, spinous process of C7-T12 Insertion: lateral 1/3 clavicle, acromion and spine of scapula Action: Elevates, rotates, retracts scapula (shurgs) Innervation: motor - spinal accessory nerve (CN XI) sensory- C30C4

Question 36

Intermeida Muscles of Back

Answer 36

1. Serratus Posterior inferior 2. Serratus posterior superior

Question 37

Deep back muscles

Answer 37

1. Splenius (superficial) 2. Erector Spinae Complex (intermediate) 3. Transversospinalis complex (deep)

Question 38

What are all deep back muscles innervated by?

Answer 38

Dorsal rami of spinal nerves

Question 39

Splenius Muscles

Answer 39

1. Splenius Capitis and cervicis Action: neck extension and ipsilaterall rotation Innervation: dorsal rami **Covers suboccipital triangle**

Question 40

Erector Spinae Complex

Answer 40

1. Iliocostalis 2. Longissimus 3. Spinalis **Action:** Spine extension, lateral flexion, controlled forward flexion

Question 41

Transversospinalis

Answer 41

1. Semispinalis 2. Multifidus 3. Rotatores Action: Posture, rotation, proprioception