The Spine

Question 1

What are the distinguishing features of thoracic vertebrae?

Answer 1

Facets on side of body (Demi-facets for articulating with head of rib)

Facets on transverse processes (for articulations with tubercle if rib)

Vertebral foramen is small and circular

Question 2

Name the regions of the spine and how many vertebrae make up each one

Answer 2

Cervical - 7
Thoracic - 12
Lumber - 5
Sacrum - 5 fused
Coccyx - 3-5 fused

Question 3

What are the gross functions of the vertebral column?

Answer 3

Centre of gravity of the body
Attachments of bones
Attachments of trunk muscles
Protection and passage of spinal cord
Segmental innervation of the body

Question 4

What is kyphosis?

Answer 4

Abnormally increased posterior convexity of the thoracic spine

Question 5

What is lordosis?

Answer 5

Lordosis is an exaggeration of the anterior (lordotic) curvature of the vertebral column in the lumbar region; may be associated with weakened trunk (anterolateral abdominal wall) musculature.

In pregnancy, women develop a temporary lordosis to compensate for alterations to their lines of gravity.

Question 6

Name some causes of lordosis

Answer 6

Muscle imbalances such as tight low back muscles, weak hamstrings, or tight hip flexors
Pregnancy
Congenital abnormality
Achondroplasia 
Rickets

Question 7

Name some causes of kyphosis

Answer 7

Developmental problems e.g.  Scheuermann's disease;
Congenital abnormality 
Nutritional eg vit D deficiency
Degenerative diseases such as arthritis
Osteoporosis with compression fractures

Question 8

What three processes emerge from the vertebral arch?

Answer 8

two transverse, one spinous

Question 9

What is the pedicle?

Answer 9

Part of neural arch between body and the transverse process

Question 10

What is the lamina?

Answer 10

Part of the neural arch between the transverse process and the spinous process

Question 11

What do the [superior and inferior] articular processes - found at the junction of the lamina and pedicle - allow for?

Answer 11

Allow for synovial joints to be formed between neural arches of adjacent vertebrae. In turn this prevents anterior displacement of the vertebrae

Question 12

Where are intervertebral discs found?

Answer 12

Between C2/3 successively to L5/S1

Question 13

What do the intervertebral discs do?

Answer 13

Allow for movement

Act as shock absorbers

Question 14

What are the two regions of intervertebral discs?

Answer 14

Nucleus pulosus and annulos fibrosus

Question 15

Describe the make up of the annulus fibrosus

Answer 15

Collagenous outer bands

Firbrocartilagenous inner bands

Question 16

What is the nucleus pulposus a remnant of?

Answer 16

The notochord

Question 17

What is a herniated disc and in what direction does it most commonly herniate?

Answer 17

The annulos fibrosus degenerates/weakens and the nucleus pulposus herniates out - most commonly in a posterior lateral direction

Question 18

What does a herniated disc compress?

Answer 18

Posteriolateral direction - compression of spinal segmental nerves

Posteriorly - compress spinal cord –> paralysis

Question 19

What two major ligaments run along the longitudinal axis of the spinal column? Which is stronger?

Answer 19

Anterior longitudinal ligament - stronger

Posterior longitudinal ligament

Question 20

Where are the Ligamentum flava?

Answer 20

Join Lamina of adjacent vertebrae - stretched by Flexion of the spine (high in elastic content)

Question 21

Where is the supraspinous ligament found and what does it do?

Answer 21

Joins tips of adjacent spinous processes - they are lax in the extended spine and taut during flexion of the spine, mechanically supporting the spinal column

Question 22

What are the inter spinous ligaments?

Answer 22

Relatively weak sheets of fibrous tissue, uniting spinous processes along their adjacent borders and fuse with supraspinous ligaments.

Only well developed in the lumber region.

Question 23

What is the nuchal ligament?

Answer 23

The nuchal ligament is a ligament that is continuous with the supraspinous ligament. It attaches to the tips of the spinous processes from C1-7 and provides proximal attachment for rhomboids and trapezius

Question 24

Describe the atlanto-axial joints

Answer 24

There are two lateral atlanto-axial joints which are formed by the articulation between the inferior facets of the lateral masses of C1 and the superior facets of C2. These are plane type synovial joints.

The medial atlanto-axial joint is formed by the articulation of the dens of C2 with the articular facet of C1. This is a pivot type synovial joint.

Question 25

What primary movement does the Atlanto-axial joint permit?

Answer 25

Rotation

Question 26

What joint permits flexion at the head ie nodding?

Answer 26

Atlanto-occipital

Question 27

What features characterise the axis?

Answer 27

The axis (C2) is easily identifiable due to its dens (odontoid process) which extends superiorly from the anterior portion of the vertebra. The dens articulates with the articular facet of the atlas, in doing so creating the medial atlanto-axial joint. This allows for rotation of the head independently of the torso and prevent horizontal displacement of atlas

Question 28

What levels are susceptible to Herniation?

Answer 28

L4/L5 L5/S1

Question 29

Name two distinguishing features of cervical vertebrae

Answer 29

Bifid process Oval transverse foramen in transverse process Large vertebral (or neural) foramen

Question 30

What is whiplash? Why is the neck susceptible to it? What are the consequences to patients?

Answer 30

Hyperextension injury - the cervical vertebrae are more flexible and the ligaments are relatively weaker. In minor cases, the anterior longitudinal ligament of the spine is damaged which is acutely painful for the patient. In more severe cases, fractures can occur to any of the cervical vertebrae as they are suddenly compressed by rapid deceleration. Again, since the vertebral foramen is large there is less chance of spinal cord involvement.

Question 31

Hangman's fracture occurs where?

Answer 31

Fracture of both pedicles or the pars interarticularis of C2- which is a bony column between the superior and inferior articular facets of the axis

Question 32

What are fractures of the dens caused by and what are the associated risks?

Answer 32

Most commonly caused by traffic collisions and falls. These are often unstable and are at high risk of avascular necrosis, due to the isolation of the distal fragment from any blood supply. As a result, fractures of the dens often take a long time to heal. As with any fracture of the vertebral column, there is also a slight risk of spinal cord involvement.

Question 33

What is a Jefferson fracture of the Atlas?

Answer 33

A vertical fall onto an extended neck e.g. diving into excessively shallow water can compress the lateral masses of the atlas between the occupital condyles and the axis. This causes them to be driven apart, fracturing one or both of the anterior/posterior arches. If the fall occurs with enough force, the transverse ligament of the atlas may also be ruptured. Since the vertebral foramen is large, it is unlikely that there will be damage to the spinal cord at the C1 level. However, there may be damage further down the vertebral column.

Question 34

What is scoliosis?

Answer 34

A lateral curvature of the spine, usually of unknown cause.

Question 35

What is cervical spondylosis?

Answer 35

A decrease in the size of the intervertebral foramina, usually due to degeneration of the joints of the spine. The smaller size of the intervertebral foramina puts pressure on the exiting nerves, causing pain.

Question 36

Describe the anatomical course of the spinal cord including where it arises and where it finishes.

Answer 36

* The spinal cord arises cranially as a continuation of the medulla oblongata (part of the brainstem). * It then travels inferiorly within the vertebral canal, surrounded by the spinal meninges containing cerebrospinal fluid. * At the L2 vertebral level the spinal cord tapers off, forming the conus medullaris

Question 37

At what level does the conus medullaris form? What happens to the cord after this level?

Answer 37

L1 and L2, after this the spinal nerves continue to branch out diagonally, forming the cauda equina.

Question 38

Name three features which distinguish cervical vertebrae

Answer 38

* Triangular vertebral foramen. * Bifid spinous process * Oval transverse foramina

Question 39

What runs through the cervical transverse foramina?

Answer 39

They give passage to the vertebral artery, vein and sympathetic nerves. The vertebral artery passes through the foramen except for C7 – C7 Foramen passes the smaller accessory vertebral veins

Question 40

What are the distinguishing features of the lumbar vertebrae?

Answer 40

* Largest of the discrete vertebrae * Lack of foramina on transverse processes * Lack costal facets on the side of the body * Vertebral foramina are triangular & small

Question 41

Describe C1 - Atlas

Answer 41

* Lacks a body * Lacks spinous process * Widest cervical vertebra

Question 42

What is sciatica?

Answer 42

A set of symptoms including pain caused by general compression or irritation of one of five spinal nerve roots of each sciatic nerve—or by compression or irritation of the left or right or both sciatic nerves.

Question 43

Name some symptoms of sciatica

Answer 43

Lower back pain, buttock pain, paraesthesia and numbness, pain or weakness in various parts of the leg and foot

Question 44

Describe the pathophysiology of sciatica and list some causes

Answer 44

Sciatica is generally caused by the compression of lumbar nerves L4, or L5 or sacral nerves S1, S2, or S3, or by compression of the sciatic nerve itself. Spinal disc herniation Spinal stenosis Pregnancy Piriformis syndrome

Question 45

How is sciatica managed?

Answer 45

Rest (spontaneous recovery in case of disc herniation/ pregnancy) Medication - pain management Surgery - discectomy

Question 46

What are the zygapophysial joints?

Answer 46

Synovial, plane joints between the articular processes of two adjacent vertebrae. There are two facet joints in each spinal motion segment.