The Lumbar Spine and Sacrum

Question 1

How many vertebrae are in the Lumbar spine?

Answer 1

5. L1 - L5 and are the largest and strongest in the body

Question 2

What type of curve dose the lumbar spine create?

Answer 2

A lordotic curve

Question 3

Are the 5 vertebrae similar in size?

Answer 3

Yep

Question 4

What is at the base of each transverse process?

Answer 4

A small prominence of bone called the accessory or mamillary process

Question 5

What is the junction of the lamina to the pedicle called in the lumbar spine?

Answer 5

The pars interarticularis

Question 6

Where does the spinal cord end?

Answer 6

Between L1 and L2

Question 7

How many vertebra does the sacrum consist of ?

Answer 7

5 vertebrae and they are fused

Question 8

What type curve does the sacrum have?

Answer 8

Kyphotic=

Question 9

What shape is the sacrum?

Answer 9

It is wedge shaped and forms the posterior walls of the pelvis

Question 10

What does the sacrum articulate with?

Answer 10

The L5 above, the coccyx below, and laterally with the articular surfaces of the iliac bones of the hip

Question 11

What is the sacro-iliac joint?

Answer 11

The joint between the pelvis and the sacram.

Question 12

What is distal to S5?

Answer 12

A triangular bone, the coccyx, consisting of 3-5 fused vertebrae.

Question 13

What are sacral foramina or pelvic foramina?

Answer 13

Foramina that lie at the lateral ends of the lines across the sacrum that represent the fused vertebrae

Question 14

What is the area lateral to the sacral foramina known as?

Answer 14

The pars lateralis

Question 15

What is the pars lateralis at S1 more commonly known as?

Answer 15

Ala

Question 16

What is the projecting edge of the first sacral vertebra called?

Answer 16

The sacral promontory

Question 17

What is the sacral promontory used for?

Answer 17

A landmark for sacral screw insertion

Question 18

What does the total pelvis or pelvic girdle consist of?

Answer 18

Two hop bones (ossa coxae), the sacrum and the coccyx.

Question 19

What does the ossa coxae articulate with?

Answer 19

The sacrum and the coccyx

Question 20

What forms the ossa coxae?

Answer 20

the fused ilium, ischium and pubis

Question 21

What type of joint is the sacro-iliac joint?

Answer 21

A true synovial joint, with capsule and cartilage

Question 22

What are the two main ligaments in the lumbar spine?

Answer 22

the anterior and posterior longitudinal ligaments

Question 23

What role do the ALL and PLL play?

Answer 23

A key role in the maintenance of spinal balance and protecting the discs

Question 24

Describe the ALL.

Answer 24

Stretches as a long dense band from the basi occiput to the sacrum
Runs along the anterior aspect of the vertebral bodies
Long fibers that run full length
Short fibers that attach to the vertebra

Question 25

Describe the PLL.

Answer 25

Stretches from the basi occiput to the sacral canal. | Does not attach to the posterior edge of the vertebral bodies.

Question 26

Describe the segmental ligaments.

Answer 26

They join the vertebral arches adn the ligamentum flavum which is its thickest in the lumbar spine Joins each lamina

Question 27

What joins the spinous processes?

Answer 27

The interspinous ligamnet.

Question 28

What attaches to the tips of the spinous processes?

Answer 28

The supraspinous ligament

Question 29

What runs between the transverse processes?

Answer 29

The intertransverse ligament

Question 30

Describe the lumbo-sacral ligament

Answer 30

Very thick and extends from the anterior-inferior aspect of the L5 transverse process to the lateral aspect of the sacrum.

Question 31

What is the Lumbo-sacral ligament also known as?

Answer 31

The sickle ligament.

Question 32

Where does the Iliolumbar ligament attach?

Answer 32

Extends from the transverse process of L5 laterally and superiorly to the iliac crest

Question 33

What is considered a near immovable part of the pelvis and why?

Answer 33

The sacro-iliac joint because it is so tightly bound and interlocked with ligaments.

Question 34

What shape is the articular surface of the iliac bone?

Answer 34

cresent shaped, concave postero-superiorly

Question 35

What are the ligaments attached to the sacro-iliac joint?

Answer 35

The ilio-lumbar ligaments sacro-iliac ligaments sacrospinous ligaments sacro-tuberous ligaments

Question 36

What is the superficial plane of the lumbar muscles made of?

Answer 36

The latissimus dorsi which arises from the lumbar aponeurosis

Question 37

What is the intermediate plane of the lumber muscles made of?

Answer 37

The serratus posterior inferior

Question 38

Name the deep muscles of the lumbar spine.

Answer 38

Transversospinalis - Runs from L1 inferiorly and laterally to the transverse processes of the underlying 4 vertebrae Interspinalis - on either side of the midline connecting adjoining spinous processes Spinalis - Lies on either side of the interspinalis and posterior to the transversospinalis Longissimus - lies lateral to the spinalis in the posterior wall of the thorax and inserts into the lower 10 ribs Iliocstalis - a thick mass forming part of the wall of the thorax

Question 39

What is the lumbar muscles vital role?

Answer 39

Maintaining an upright posture | Maintains the lumbar lordosis

Question 40

What are the two main anterior lateral muscles in the lumbar spine?

Answer 40

Quadratus lumborum - runs between the last rib, the iliac crest and the vertebral column Psoas - originates from the transverse process and posterolateral aspect of the vertebral bodies from T12 to L5, its fibres run inferiorly and laterally to blend with the fibres of the iliacus muscle.

Question 41

What is the inferior region of the spinal cord?

Answer 41

Conus medullaris and usually lies between the T12 and L1.

Question 42

Where is the termination of the spinal cord proper?

Answer 42

The conus medullaris

Question 43

At the point of the conus medullaris the spinal cord becomes a tapering band of tissues called?

Answer 43

Filum terminale

Question 44

What is the name of the spinal nerve roots that emerge from around the filum terminale?

Answer 44

The cauda equina

Question 45

How many pairs of lumbar spinal nerves are there?

Answer 45

5 pairs of sacral and 1 pair of coccygeal

Question 46

What is each nerve a combination of?

Answer 46

Motor and sensory fibres

Question 47

Where does the L4 nerve root exit?

Answer 47

L4/5 lateral foramen near the L4 pedicle.

Question 48

What are nerve fibers collected together called?

Answer 48

Rami

Question 49

What are groups of rami called?

Answer 49

Plexuses

Question 50

What types of plexuses are there in the lumbar spine?

Answer 50

Lumbar plexus | Sacral plexus

Question 51

What comprises the lumbar plexus?

Answer 51

The ventral rami of L1-L4 nerves

Question 52

What comprises the sacral plexus?

Answer 52

Fibres from the ventral rami of the nerves at L4, L5 and S1-S3.

Question 53

What comes off of the abdominal aorta?

Answer 53

Lumbar arteries which run beneath the psoas muscle adherent to the vertebral bodies.

Question 54

What comes off of the lumbar arteries?

Answer 54

Posterior and abdominal brances

Question 55

What comes off of the posterior artery?

Answer 55

The spinal artery

Question 56

Which level does the abdominal aorta bifurcate?

Answer 56

L4