Week 1 - E - Anatomy 2 - Back, spine and spinal cord

Question 1

What is the posterior aspect of the trunk (torso) known as?

Answer 1

The back

Question 2

What are the main functions of the back?

Answer 2

Maintaining posture and Movements of limbs and trunk

Question 3

What is the first palpable spinous process known as? and how common is it to be the first palpable?

Answer 3

This would be C7 - vertebral prominens 70% of people have this as the most common

Question 4

Can feel spinous process down all down the spine What are the skin dimples at the lower back indicating the level of? What is the anatomicl terminology for the buttcrack?

Answer 4

This indicate the positions of the posterior superior iliac spines and this is roughly the start of the sacrum This would be the intergluteal cleft

Question 5

The back has extrinisic and intrinsic muscles Name the extrinsic muscles of the back

Answer 5

Trapezius Rhomboids Levator scapulae Lattismus dorsi

Question 6

What are the three parts of the trapezius muscles? What nerve supplies the trapezius?

Answer 6

Have the Descending trapezius - superior Transverse trapezius - middle Ascending trapezius - inferior Supplied by the spinal accessory nerve (CN XI)

Question 7

What is the function of the trapeius muscles?

Answer 7

The descending part of the trapezius muscle supports the arms. The transverse part retracts the scapulae, and the ascending part depressed the scapula/shoulder

Question 8

What muscles sit slightly deep to the trapezius muscles?

Answer 8

The major and minor rhomboid

Question 9

What is the function of the levator scapulae muscle? What is the function of the rhomboids? What is the primary function of the lattismus dorsi?

Answer 9

Levator scapula lifts the scapula The rhomboids cause retraction of the scapulae ie pulls the blades medially Primary funcion is adduction of the arm (also causes internal rotation of the arm)

Question 10

As a whole the extrinsic back muscles move the upper limb Which extrinsic back muscles inserts into the thoracolumbar fascia and what is its nerve supply?

Answer 10

This would be the latissimus dorsi supplied by the thoracodorsal nerve

Question 11

As stated the function of the extrinsic back muscles are to move the upper limb What is the function of the intrinsic back muscles and what are the two groups of muscle?

Answer 11

The intrinsic back muscles maintain posture and move the spine Have the erector spinae superficially to the transversospinalis

Question 12

Inferiorly, what does the common tendon formed by the three erector spinae muscles attach to?

Answer 12

Attaches to the sacrum and iliac crests

Question 13

Superiorly the erector spinae muscles will have three different attachment points Name the muscles with their attachment points?

Answer 13

Iliocostalis - attaches from iliac crests to the ribs (between rib angle and tubercle) Longissimus - attaches to the transverse process of the vertebrae Spinalis - attaches to the spinous processes of the vertebrae

Question 14

Where do the trasnversospinalis muscles lie?

Answer 14

They are located within the grooves between the transverse and spinous processes of the vertebra

Question 15

What function do both the intrinsic muscles of the spine help to maintain? What action is cause by bilateral and unilateral contraction of the erector spinae muscles?

Answer 15

Help to maintain posture and support the spine Bilateral contraction - extension of the spine Unilateral contraction - lateral flexion of the spine

Question 16

What are the muscles that bring about flexion of the spine? (hint they are not the extrinsic or intrinsic back muscles)

Answer 16

This would be the rectus abdominis (abs) and the psoas major muscle

Question 17

What is the curved tendinous intersection found on either side of the rectus abdominis muscle? Name the muscles of the anterolateral abdominal wall?

Answer 17

This is known as the linea semilunaris external oblique, internal oblique, transversus abdominus

Question 18

What function do the transversospinalis muscles provide?

Answer 18

They allow rotation of the spine

Question 19

What are the two muscles of the posterior abdominal wall?

Answer 19

The psoas major and the quadratus lumborum

Question 20

33 vertebrae in total 7 cervical (C1-C7) 12 thoracic (T1-T12 5 lumbar (L1-L5) 5 sacral (fused to form 1 sacrum) 4 coccygeal (fused to form 1 coccyx) How do the size of vertebra change from superior to inferior?

Answer 20

Increase in size moving as they have to bear more weight Become smaller again once reaching the sacrum as the weight is transferred to the hip bones

Question 21

What are the functions of the vertebral column?

Answer 21

They support the head and trunk when upright Protect the spinal cord and the nerves by providing a central axis

Question 22

What are the four curvatures of the spine?

Answer 22

Cervical lordosis Thoracic kyphosis Lumbar lordosis Sacral kyphosis

Question 23

In the spine their are pimrary and secondary curvatures Anything with a primary curvature is said to have an anterior concavity therefore which vertebrae have primary curvature? Why does primary curvature develop?

Answer 23

The thoracic and sacral vertebrae have primary curvature The primary curvatures develop during foetal development

Question 24

The secondary curvature of the spine (posterior concavity) develops when the child develops head control and when learns how to sit unsupported At what milestone does a child sit upright and have head control? Which vertebrae are said to have secondary curvature?

Answer 24

Head control - 3months Sits unsupported - this would be 8/9months Secondary curvature is for the cervical and lumbar vertebrae

Question 25

Some deviations – can get kyphosis which is an exaggeration of a primary curvature typically in the thoracic kyphosis Exaggeration of the secondary curature is seen as a lordosis When is a lordosis typically seen?

Answer 25

Typically seen in pregnant women as they tend to bend back

Question 26

a medical condition in which a person’s spine has a sideways curve. What is this?

Answer 26

Scoliosis

Question 27

What connects the vertebral body to the vertebral arch of a particular vertebrae? What connects the transverse process to the spinous process of a particular vertebrae?

Answer 27

The pedicle connects vertebral body to vertebral arch The lamina connects spinous to transverse process

Question 28

Where in the vertebrae does the spinal canal run? How many articular processes exist per vertebrae?

Answer 28

The canal runs in the vertebral foramen formed by the vertebral body and arch 4 articular processes - 2 inferior and 2 superior - form synovial facet joints with adjacent vertebrae

Question 29

What forms a spinal nerve and where is it found?

Answer 29

Formed by anterior and posterior roots joining at the intervertebral foramen

Question 30

How is a facet joint formed?

Answer 30

it is formed by the adjacent articular process of the vertebra (inferior articular processes of one vertebra and superior articular processes of one below)

Question 31

What vertebra do intervertebral discs not exist between?

Answer 31

Dont exist between C1/2 and the sacrum/coccyx Account for roughly 20-25% of the spinal length

Question 32

What are the two parts of the intervertebral discs? Which is the layer that can herniate?

Answer 32

The outer tough annulus fibrosis The inner soft nucleus pulposus The nucleus pulposis can herniate

Question 33

Which ligaments connect adjacent laminae in the spinal cord together? What do the laminae in the vertebra connect again?

Answer 33

The ligamentum flavum connects these The lamina are what connect the transverse to spinous processes

Question 34

What ligament acts to prevent over flexion of the spine? where does this ligament lie? Which muscles cause flexion of the spine?

Answer 34

The posterior lonitudinal ligament acts to prevent over flexion Lies immediately posterior to the vertebral bodies and runs the length of the spine The rectus abdomins and psaos major cause flexion of the spine

Question 35

What ligament acts to prevent over extension of the spine? where does this ligament lie? Which muscles cause extension of the spine?

Answer 35

The anterior longitduinal ligament - this ligament is broad and strong Lies on the anterior surface of the vertebral bodies The erector spinae cause extension of the spine

Question 36

What do the supraspinous and interspinous ligaments connect? Which is stronger and which is weaker?

Answer 36

The supraspinous ligament connects the tips of adjacent spinous processes - strong and fibrous The interspinous ligament connects the superior and inferior surfaces of adjacent spinous processes - weak and membranrous

Question 37

Common typical features of cervical vertebrae: transverse foramen bifid spinous process - bifid means split triangular shaped vertebral foramen Which are the three abnormal cervical vertebra?

Answer 37

C1 - atlas C2 - axis C7 - vertebra prominens

Question 38

C1 does not have a body or spinous process What does it have instead? What does C2 have that acts as the body of C1? What is special about C7?

Answer 38

C1 instead has an anterior and posterior vertebral arch C2 has an odontoid process which basically acts as the body of C1 C7 has an extra long spinous process (non bifid) and is most commonly the first palpable vertebra

Question 39

Describe the features of an atlanto-occipital joint? What movements does this joint allow?

Answer 39

The joint exists between the occipital condyles and the superior articular facets of the atlas It allows mainly the movement and flexion and extension but also a little lateral flexion and rotation

Question 40

It is important not to miss out C1 when counting vertebrae on the radiograh What can you see about c7 that makes it clear how it the first palpable and not c6?

Answer 40

Can see on the Xray that C7 is very close to the surface of the skin hence the vertebra prominens whereas the spinous process of c6 is not as long and wont reach

Question 41

What are the 4 stages for cervical vertebrae dislocation? Why can the spinal cord avoid damage during cervical disloaction?

Answer 41

Stage 1 - flexion sprain Stage 2 - anterior subluxation - 25% translation Stage 3 - 50% translation Stage 4 - complete dislocation Cord an escape damage in cervical dislocation as there are large vertebral foramen in the cervical vertebrae compared to the rest of the column

Question 42

What are the 3 synovial articulations between the atlas and axis forming the atlantoaxial joint? What is the main movement at this joint? What holds the odontoid process in place?

Answer 42

2 articulations between inferior articular processes of the atlas and superior articular processes of the axis 1 articulation between the anterior arch of the atlas and odontoid process (dens) of the axis Main movement is rotation Transverse ligament of atlas holds the odontoid process in place

Question 43

Sacrum fuse by time we get to adulthodd The very defined prominence of S1 is known as sacral promononty – more prominent in males What extends out from the sacral prominence used for the sarcoiliac joints?

Answer 43

This is the ala of the sacrum - fuses with the ilium

Question 44

On anterior and posterior surface of the sacrum there are numbers of foramina for anterior and posterior rami respectively Two halves of the neural arch didnt quite fuse at the inferior aspect of posterior sacrum and therefore this region can be used to administer anesthesia. What is this palpable feature known as?

Answer 44

This is the sacral hiatus

Question 45

Where does the spinal cord begin? What is the end of the spinal cord known as and at what level is this? What runs in the central aspect of the spinal cord containing what? What is the continaution of the spinal cord known as?

Answer 45

Spinal cord begins at the foramen magnum where it is continuous with the medulla oblangata It ends at the vertebral level L2 - known as the conus medullaris The central canal runs in the centre of the spinal cord containing CSF - continued from the 4th ventricle COntinuation of the spinal cord is known as the cauda equina

Question 46

Although the spinal cord most commonly ends at L2, what can it range from due to anatomical variation? What is the delicate strand of fibrous tissue continuing from the conus medullaris which fuses with the coccyx helping anchor the spinal cord? What are the two enlarged areas of the spinal cord and why?

Answer 46

Can end anywhere from T12 to L3 This is the filum terminale - joins with coccyx from conus medullaris The cervical and lumbar enlargements and this is because they contain the neurones from the upper and lower limbs

Question 47

The spinal cord is surrounded by 3 layers of meninges Which two layers are often joined to one another and therefore difficult to tell apart? What is the fat layer known as between meninges and vertebral foramen? What are the veins in this layer known as?

Answer 47

The arachnoid and dura mater The fat layer is the epidural fat - the veins here are known as epidural venous plexus and can beel during epidural anaesthesia resulting in epidural haemorrhage

Question 48

What is the arterial blood supply to the spinal cord?

Answer 48

Anterior longitudinal artery and 2 posterior longitudinal arteries Segmental arteries derived from verterbral and intercostal arteries Radicular arteries that travel on the dorsal and ventral rootss

Question 49

Name the two vessels that are covered?

Answer 49

top left - posterior internal vertebral venous plexous Bottom right - anterior spinal artery

Question 50

Name where the two black lines are coming from?

Answer 50

Yellow - epidural fat Blue - epidural venous plexus Can see the anterior spinal artery (and the internal vertebral venous plexus) are within the dura mater, epidural fat outside dura mater