Clinical Correlations: Spine and Back 9/24

Question 1

Scoliosis

Answer 1

• most common deformity, affects pre-pubescent girls most

Causes:

• idiopathic (genetic ~80%)
• congenital: hemivertebrae
• shorter leg
• spina bifida, MD or osteoporsis
• primary curve (i.e due to shorter leg- spine bends towards longer leg)
• secondary curve (compensatory)
• spinous processes rotate toward the
• harrington rods used to reduce this

Question 2

Compression Fractures

Answer 2

• can be due to traumatic load bearing (i.e. diving and head contacting ground) or can be pathological.

–> osteoporotic: weaked bony trabeculae coupled with reduced thickness of cortiacl bone –> compression of vertebral bodies (when lose density, vertebrae become wedge shaped and it increases kyphotic curve)

–> neoplastic : metastasis from prostate/breast/ovary/hodgkin’s lymphoma to vertebral bodies via basivertebral veins of Batson’s plexus –> tumors errode trabeculae

Question 3

Dislocation/Fracture Dislocation of Cervical Vertebrae

Answer 3

• due to the disposition of the articular facets as well as the reduced mass of the region, the ervical vertebrae are more subject to dislocation when compared to other areas of the spinal column
• Specific dislocations/fractures: Jefferson Burst (atlas), hangman’s (axis), dens fracture, rupture of the transverse ligament of the atlas, rupture of the alar ligaments

Question 4

Jefferson Burst

Answer 4

Fracture to the arches of the atlas due to excessive force to the crown of the skull, forcing the lateral masses of the atlas laterally

• this would be further complicated by the rupture of the transverse ligament of the atlas
• because there is no body here, the burst occurs in the anterior and posterior arch of fracture

Question 5

Hangman’s Fracture

Answer 5

• forceful hyperextension of the head on the neck caues bilateralfracture through the pars interartiuclaris

Question 6

Fracture of odontoid process

Answer 6

• “dens” fracture
• may fracture from the body of CV2 completely or fracture with a part of it
• disarticulation of dens = complete fracture —> avascular necrosis (dens dies b/c no blood supply) –> results in atlas moving in A-P direction and impinging on nerve similar to the rupture of the transverse ligament- though not as severe because it is not pushedd against the dens
• with transverse ligament of the atlas intact, dens and anterior arch of the atlas remain attached
• disar

Question 7

rupture of the transverse ligament of the atlas

Answer 7

• this allows the atlas to move freely (atlanto-axial subluxation) in an A-P direction relative to the axis allowing the spinal cord to be piched between the body and the dens of the axisand the posterior arch of the atlas.
• can result in quadraplegia or death
• NOTE: this ligament is lax or missing in down’s syndorme which increases their susceptibility to atlanto-axial sublation

Question 8

rupture of alar ligaments

Answer 8

• allows for increased rotation of the skull and CV1 on CV2 (~30 degrees more)
• cause: increased flexion with rotation of the skull (flexion limits the rotation of the atlas on the axis and places increased stress on the alar ligaments)

Question 9

Spondylolysis

Answer 9

• a condition whose defect (can be trauma induced) exists in the pars interacticularis of the neural arch between superior and inferior articulating processes

Question 10

Spondylolisthesis

Answer 10

• (bilateral spondylolysis)- located at one vertebral segement allows that vertebral body as well as the entire spinal column above, to slide forward on the vertebra below. the most common site for this to occus is LV5 on SV1.
• scotty dogs
• in lumbar region, breaks closer to lamina
• in cervical region, breaks closer to pedicle

Question 11

spina bifida occulta

Answer 11

• least serious type of spina bifida
• neural arch defect at LV5 or SV1 (affects 25% of population)
• may be complete or partial; usually spinous process is absent because lamina don’t fuse properly
• tuft of hair located here

Question 12

spinal involvement of osteoarthritis

Answer 12

- results in spondylosis: narrowing of the IV foramen - pinching of nerves

• this is degenerative change involving the vertebral body adn adjacent IV disk. With increased age, the water contect of cartilage that covers the articular surfaces of the vertebral bodies increase while protein decreases.
• degeneration of articular cartilage leads to inflammation and osteophyte (bone spur) formation
• with increased degen. of articular cartilage, disk space narrows. Coupled with osteophyte formation, IV foramina become narrowed (spinal stenosis) and spinal nerves may be impinged, leading to radiculopathy (pain districuted along the path of a dermatome)
• Following procedures to relieve symptoms of radiculopathy associated with stenosis
• laminectomy: surgical removal of a spinal process and the adjacent lamina to gain access to the spinal canal for purpose of relieve pressure like osteophytic growht
• • faoraminotomy - surgican enlargement of hte IV foramen to relieve pressure placed on spinal nerves

Question 13

spinal stenosis

Answer 13

• narrowing of IV foramina (can be seen in osteoarthritis)

Question 14

Osteoarthritis of zygapophyseal (facet) joints

Answer 14

• same pathophysiology as spondylosis
• can affect all facet joints of the spine
• leads to further narrowing of the IV foramina

NOTE: aside from the radicular pain theat emanates from nerve root impinement, articular pain fibers also exist which respond to a high degree due to the inflammation of hte joint

Question 15

whip lash injury

Answer 15

• rapid hyperextensionof the spinal column can rupture the anterior longitudinal spinal element and may even avulse a portion of the anterior surface of the vertebral body at the point at which the ligament ruptures

Question 16

Ankylosing Spondylitis

Answer 16

• ultimately results in ossification of annulus fibrosus of IV disks, apopphyseal joints, and anterior longitudinal and interspinal elements –> results in fusion of joints/ligament –> results in a fused spine

Progression of the DIsease:

1. Inflammation of sacroilial and spinal elements
2. ostephytic bone growth into ligaments
3. fusion of the spine

• makes arms swing/normal gait impossible
• occurs most often in men in 3rd/4th decade
• genetic mutation in protein HLA B-27
• radiological mark is “bamboo spine”

Question 17

Ruptured disk

Answer 17

• tearing of the annulus fibrosus WITHOUT protrusion of the nucleus pulposus

Question 18

Herniated Disk

Answer 18

• tearing of the annulus fibrosus WITH protrusion of the nucleus pulposus (this happens more in areas of greater mobility - cervical and lumbar)
• usually due to suddent and violent hyperflexion of spine.
• IV disk becomes comppr=ressed anteriorly and stretched posteriorly
• if the annulus tears, the nucleus can herniate posteriorly into the spinal canal

*** Most herniations occur posteriolaterally (directed by the posterior longitudinal ligament) –> impinges on roots of spinal nerves. Most occur in L4-L5, L5-S1 reion where disks are largest and weight born e is the greatest movement in the plane of flexion and extension.

NOTE: pain that is easily localized is acute pain and results from the actual tear of the annulus, regional inflamation as a result of the herniated nucleus and pressure placed on the posterior longitudinal ligament via the bulgin disk. ….. Chronic pain associated with herniation is due to compression of the spinal nerve root resulting in a continual low grade depolarization that results int he patient “feeling” pain int eh receptive field of the compressed nerve.

NOTE: herniations that occur int eh cervical region affect spinal nerves at the same level as the herniation. herniations that occur in lumbar regions, due to the angle at which the spinal nerves descend fromt he spinal cord relative to the herniated IV disk affect the spinal nerve one or more segments below.

Question 19

stages of IV disk herniation

Answer 19

1. disc degeneration: chemical changes associated with aging cause disks to weaken, but without herniation
2. prolapse: the form or position of the disc changes with some slight impingement into the spinal cord (bulge/protrusion)
3. extrusion: the gel-like nucleus pulposus breaks through the annulus fibrosus but remains within the disk
4. sequestered disc: the nucleus pulposus breaks through the annulus fibrosus and lies outside the disk in the spinal cord

Question 20

Ischemic Paralysis of the Spinal Cord

Answer 20

• Anterior and Posterior spinal arteries run the full length of the spinal fcord
• without ramification via spinal and radicular branches of segmental arteries (branches of arteries which parallel the spinal column and send branches into the IV foramen to supply the spinal column, spinal nerve roots, and spinal cord) the anterior and posterior spinal arteries would not be patent in their entire length
• interference in the supply of blood provided by the segmental arteries due to trauma, cross-clamping the aorta or aortic aneurysm can lead to ischemia of the spinal cord –> paresthesia or paraplegia in the area affected by the ischemia

Question 21

Lumbar Puncture

Answer 21

• “spinal tap”
• removal of CSF from subarachnoid space via a needle which passes between contiguous protions of the ligamentum flavum
• patient flexes spine to increase distance between lumbar laminae
• needle passes through the dura and arachnoic mater to remove frluid from the subarachnoid space
• in adult, LP proceeds in midline between LV3/4 or LV4/5 as the spinal cord ends at the L1/2 interspace. in children care must be taken as cord ends at L4/5.

Question 22

Caudal Epidural Anesthesia

Answer 22

• needle passed through the sacral hiatus and into the sacran canal to deliver anesthesia to the surface of the cauda equina
• used to deliver “saddle” block type of anesthesia for child birth; relieves pelvic pain without removing motor control which originates at higher spinal levels

Question 23

tension headaches

Answer 23

• greater occipital nerve is trapped in deep back muscles of the semispinalis capitis. When this is continually tensed it triggers pain fibers that extend to the vertex of the skull