Spinal Anatomy Exam 3

Which lumbar vertebrae are typical and atypical?

Typical-> L1-L4

Atypical-> L5

How do pedicles present on lumbar vertebrae?

Short; strong; massive circumference

Posterior orientation

How do the vertebral notches present on the lumbar vertebrae pedicles?

Superior notch: Slight

Inferior notch: Deep

Where do the spinal nerves exit in the lumbar region?

below the vertebral body

How does the laminae present in the lumbar region?

Broad; thick

Asymmetric in superior-inferior length

Where does the ligamentum flavum cover on the lumbar laminae?

Superior-inferior margins

How do the superior and inferior margins present on lumbar laminae?

Superior: Inner surface curved and smooth

Inferior: Inner surface rough for LF attachment while supporting inferior articular process

Where does the spinal cord end and what does it make an excellent site for/

L1, Spinal tap (L3-L4)

How does the spinous process present in lumbar vertebrae?

Flat, Large, Rectangular spinous tubercle

Broad from superior to inferior

Narrow from left to right

Increase in length

What is the touching of adjacent spinous processes called?

Baastrup's syndrome (Kissing spines)

What muscles attach to the spinous process of lumbar vertebrae?

Latissimus dorsi

Serratus posterior inferior (L1-L3)

Longissimus thoracis (L3,L4)

Spinalis thoracis (L1,L2)

Multifidus

Rotators

Interspinalis

What ligaments attach to the spinous process of the lumbars?

Interspinous

Supraspinous

What is in the L1 vertebral foramen?

Conus medullaris

What is in the L2 vertebral foramen?

Cauda equina

What is the accumulation of fat that can displace/deform the dural sac?

Lipomatosis

What is tethered cord syndrome?

Stretching of the spinal cord because of adipose of lipoma in the filum terminale

How does the vertebral body present in the lumbars?

Large, transversely broad, reniform shaped

What happens to the vertebral body as we age?

Decreases in body height and increase in circumference

what creates the lordotic curvature in the lumbar spine?

IVD height is greater anteriorly

What contributes to lumbar lordosis?

Increase in height of anterior L4 and L5 VB and all IVDs (discs contribute more to lordosis)

What are the muscle attachments in the lumbar vertebral body?

Psoas Major (T12-L5)

Psoas Minor (T12-L1)

What ligaments attach to the lumbar vertebral body?

ALL

PLL

Transforaminal ligament

Corporotransverse ligaments

Hofmann ligaments

Where does the superior transforaminal ligament attach?

Vertebral body to inferior articular process of same vertebra

Where does the middle transforaminal ligament attach?

IVD to inferior articular processes of segment above

Where does the inferior transforaminal ligament attach?

Vertebral body to superior articular process of same vertebra

Where does the superior corporotransverse ligament attach?

Vertebral body and IVD to transverse process of vertebra below

Where does the inferior corporotransverse ligament attach?

Vertebral body and IVD to transverse process of vertebra above

What are the Anterior Hofmann ligaments known as?

Midline Hofmann ligaments

Midline meningovertebral ligaments

What are the posterior Hofmann ligaments known as?

Posterior meningovertebral ligament

Posterior epidural ligament

What are the lateral Hofmann ligaments also known as?

Lateral meningovertebral ligament

Lateral epidural ligament

Where does the anterior Hofmann attach?

PLL and/or vertebral body to anterior dura mater in anterior epidural space

Where does the posterior Hofmann attach?

Ligamentum flavum and/or lamina to posterior dura mater in posterior epidural space

Where does the lateral Hofmann attach?

Pedicle to the lateral dura mater in the lateral epidural space

May occur as extensions of dura mater over nerve roots

Where is the attachment for ligaments in the epidural space in the cervical and upper thoracic spinal canal?

Ascend from the dura to the vertebral segment above

Resists caudal movement

Where is the attachment for ligaments in the epidural space in the Lumbar region?

Descend from their dura attachment to the vertebral segment below

Resists cranial movement during flexion

How do the Transverse process of the lumbar vertebrae present?

Posterolateral from the lamina-pedicle junction

Anterior to articular processes; posterior to IVF

What are the muscle attachments to the Transverse process? (lumbar)

Psoas Major

Quadratus Lumborum

Longissimus thoracis

Rotator longus, brevis

Intertransversarii

What are the ligament attachments to the transverse process? (lumbar)

Lumbocostal

Intertransverse

Corporotransverse

How does the accessory process present in lumbar spine?

Projects posteriorly and inferiorly on transverse process near lamina-pedicle junction

What is the accessory process an attachment site for?

Longissimus thoracis

Medial intertransversarii lumborum

What is the space between the superior and inferior articular processes called?

Pars interarticularis

What are pars interarticularis defects referred to as?

Spondylolysis

Common causes of back pain

Unilateral or bilateral fracture at the pars

How does the superior articular facet present?

Concave

Backwards, Upward, Medial (BUM)

How does the inferior articular facet present?

Convex

Forward, Lateral, Downward (FoLD)

Whats special about the lumbars during embryonic development?

2 additional secondary ossification centers

On Posterior aspect of superior articular process and become mammillary process

7 total secondary

How does the mammillary process present?

Project posteriorly from superior articular process

What is the mammillary process an attachment site for?

Multifidus

Intertransverse mm

Mamillo-accessory ligament

How does the zygopophysis change as we age?

Infants: Coronally positioned

Maturation: Sagittal position

What causes the zygopophyseal joint to change?

Posture

Ability to walk

Transference of weight from VB to zygopophysis

Formation of lumbar lordotic curvature

How does the Atypical L5 VB present?

Largest

Anterior height sig. greater than posterior

Wedge-shaped

What is the L5 VB an attachment site for?

Psoas Major

ALL

PLL

transforaminal lig.

How does the L5 transverse process present?

Project superolaterally, shortest lumbar TP

Originates from VB, pedicles and pars interarticularis

What are the muscle attachments of the L5 transverse process?

Psoas Major

Quadratus lumborum

Longissimus thoracis

Rotator lumborum

Intertransversarii

What is the accessory process of L5 an attachment site for?

Longissimus thoracis

medial intertransversarii lumborum

Mammillo-accessory ligament

What is the intertransverse ligament replaced by at L5?

Lumbosacral ligament

Iliolumbar ligament

Anterior, posterior, superior, inferior and vertical iliolumbar ligament

What is the orientation of the L5 articular process?

Backward, Upward, Medial (BUM)

What is the orientation of the Inferior articular facet?

Forward, Lateral, Downward (FoLD)

What are the muscle attachments at the L5 spinous process?

Longissimus thoracis

Multifidus

Rotator Lumborum

Interspinalis

What is it called when the spinous process becomes elongated and, during extension, may enter the sacral spinal canal?

Knife-Clasp Syndrome

What is Spondylosis?

"Condition" of a vertebra

What are common conditions of the spine?

Osteoarthritis

Degeneration of spine

Acquired or age-related changes

What is spondylolysis?

Defects of the lamina

"Separation of parts" (Pars Interarticularis)

me when

me when I

Why is L5 the most vulnerable to acute pars fracture?

Narrow distance b/w inferior facets

L4 inferior and S1 Superior have a pincher effect of L5 Pars

Spondylolysis should raise suspicion with back pain in what athletes and why?

Football linemen, Cheerleaders, Gymnastics, Weightlifters and Divers/Swimmers

Repetitive Hyperextension/rotation of lumbar spine

What is the "Scotty Dog"?

Oblique X-ray of lumbar region

Ear-> Superior articular process

Eye-> Pedicle

Nose-> TP

Neck-> Pars interarticularis

What is the "Collared Scotty Dog"?

Fracture/Cleavage (sponylolysis) location on the pars interarticularis

What do we associate Lumbar Spondylolysis with?

Upright body posture

Never seen in non-erect species

What spinal defect often had lumbar spondylolysis associated with it?

Spina Bifida (63% occulta)

Where does lumbar spondylosis commonly occur with sex-location bias?

Male -> L5/S1

Female -> L4/L5

Complete reunion of bony parts are observed in some patients what is this called?

Spondylolysis ligament

What is Lumbar pseudarthrosis?

Broken bone fails to heal after a fracture or a spinal fusion surgery fails

Why does movement stimulate pain in lumbar spondylolysis?

Richly innervated by nociceptive fibers

Why does cervical spondylolysis occurr?

Congenital

Lack of cartilage formation in neural arch

More common in males at C6

What population does sacral spondylolysis associate with?

Alaskan population (94% male)

Associated with kayaking and harpooning

What is spondylolisthesis?

Slippage (usually accompanied with separation)

Primarily anterior slippage

What is posterior vertebral slippage called?

Retrospondylolisthesis (retrolisthesis)

What are the 5 common types of spondylolisthesis?

1) Congenital/dysplastic

2) Isthmic

3) Degenerative

4) Traumatic

5) Pathological

What is congenital/dysplastic spondylolisthesis (type 1)?

Associated with a defect in the L5 vertebral arch

High correlation with spina bifida occulta and S1 nerve root compression

What is Isthmic Spondylolisthesis (type 2)?

3 subtypes

1) Lytic/stress-fracture-induced

2) Elongated but intact pars interarticularis

3) Acutely fractures pars interarticularis

What is Lytic/stress-fracture-induced Isthmic spondylolisthesis?

Associated with pars defect

More common in males at L5/S1, women w/ 3+ children, younger population in activities with repetitive stress

What is Degenerative Spondylolisthesis (type 3)?

Associated w/: Osteoarthritis, IVDD, Facet remodelling

Common at L4/L5 females

Oophorectomy

IVF encroachment with stenosis compromises spinal nerve

What is Oophorectomy?

Decr. hormone levels leading to decr. elasticity of paraspinal ligaments. Incr. risk for osteoporosis

What is traumatic spondylolisthesis (type 4)?

Fracture of nerual arch components

6 types

What are the 6 types of Traumatic spondylolisthesis?

1) Unilateral or bilateral facet jump/dislocation

2) Unilateral or bilateral facet fracture

3) Acute unilateral or bilateral pars fracture

4) Acute fracture to previous fusion mass

5) Bilateral pedicle fracture

6) Complex fracture dislocation with VB involvement

What is Pathologic spondylolisthesis (type 5)?

Resulting from specific disease processes

What is a specific disease associated with pathologic spondylolisthesis?

Paget disease or Osteogeneis Imperfecta ("brittle bone disease")

Bone mineral abnormal distribution-> remodelling of neural arch

What spinal manifestations occur with type 5 spondylolisthesis?

Scoliosis, kyphosis, craniocervical junction abnormalities, lumbosacral pathology

What are the features of the sacrum?

S1-S5 fusion

Height is larger in males

Width is larger in females

Kyphotic

Curve becomes more pronounced with age

What is increased kyphosis of the sacrum and slope of S1 bony endplate associated with in children?

L5/S1 spondylolisthesis

How many primary centers of ossification are in the sacrum?

One in centrum

Two in neural arch

Whats special about the development of the costal element in the sacrum?

Develop separately and fuse with neural arch (forms lateral masses)

How many secondary centers of ossification are there in the sacrum and when do they fuse?

Superior-inferior aspect of body

Lateral-anterior aspect of costal element

Spinous tubercles

Auricular surface

Most fuse by 25

What are the features of the Base (superior) view of the sacrum?

S1 body kidney-shaped

Last true IVD b/w L5 & S1

Triangular vertebral foramina (sacral canal)

Anterior lip of S1 body known as Sacral Promontory

Sacral Ala is the S1 TP and CE

What are the features of the Pelvic (anterior) view of the sacrum?

Transverse ridges (IVD remnants, fusion begins at puberty and completed by 25-30)

Anterior (ventral) sacral foramina (greater than dorsal sacral foramina)

Ventral primary rami (S1-S4) innervate pelvis and lower extremities, accompanied by lateral and median sacral arteries & segmental veins

What are the features of the Dorsal (posterior) view of the sacrum?

S1 superior articular process reinforced by mammillary process

Superior Articular Facet (BUM)

5 sacral crests

Sacral cornu (S5 inferior articular facet)

Sacral hiatus (inferior opening of sacral spinal cord)

Where are the 5 sacral crests?

Median sacral crest (1) [laminae/spinous tubercle fusion]

Intermediate sacral crest (2) [articular process/facet fusion]

Lateral sacral crest (2) [transverse tubercle fusion]

What are the features of the lateral view of the scarum?

Sacral promontory

The auricular surface articulates with the auricular surface of the ilium (extends from S1-S3 costal elements)

What are the features of the Apex (inferior) view of the sacrum?

Formed by S5 VB

3mm of IVD space b/w S5 and coccyx (sacrococcygeal joint)

What is the sacrococcygeal joint?

Cartilaginous symphysis joint

Occasionally synovial joint develops here

Region may completely fuse in older invidividuals