Chapter 2: Back

Question 1

abnormal curvatures of vertebral column

Answer 1

-from developmental anomalies & pathological processes like osteoporosis
-osteoporosis- net demineralization of bones -> disruption of normal balance of calcium deposition and resorption
-bones become weakened and brittle -> fracture
-can occur in all vertebrae but is most common in thoracic and postmenopausal women

Question 2

excessive lumbar lordosis

Answer 2

-anterior rotation of pelvis
-abnormal increase in lumbar curvature
-more convex anteriorly
-associated with weakened trunk musculature especially of anterolateral abdominal wall
-common in pregnancy

Question 3

excessive thoracic kyphosis

Answer 3

-abnormal increase in thoracic curvature
-vertebral column curves posteriorly
-results from erosion of the anterior part of one or more vertebrae
-loss of height

Question 4

scoliosis

Answer 4

-abnormal lateral curvature
-rotation of vertebrae
-spinous process turns toward the cavity of abnormal curvature
-common in pubertal girls
-asymmetric weakness of intrinsic back muscles (myopathic scoliosis), failure of half of a vertebra to develop (Hemivertebra), and a difference in length of the lower limbs are causes of scoliosis

Question 5

spina bifida occult

Answer 5

-most common congenital anomaly of the vertebral column
-laminae (embryonic neural arches) or L5 and/or S1 fail to develop normally and fuse
-24% of people
-concealed by skin, but location is often indicated by tuft of hair
-spina bifida cystica- one or more vertebral arches may almost completely fail to develop -> associated with herniation of meninges and/or spinal cord
-meningomyelocele- neurological symptoms usually present -paralysis of limbs and disturbances in bladder and bowel control

Question 6

laminectomy

Answer 6

-surgical excision of 1 or more spinous processes and their supporting laminae
-commonly used to remove most of the vertebral arch by transecting the pedicles
-provide access to vertebral canal -> relieve pressure on spinal cord or nerve roots usually caused by tumor, herniated IV disc, or bony hypertrophy

Question 7

fractures of vertebrae

Answer 7

-result from sudden forceful flexion
-MVA
-usually crush or compression fracture
-if violent anterior movement and compression occur a vertebra may be displaced anteriorly on the vertebra inferior to it -> dislocates and fractures the articular facets between the 2 vertebrae and ruptures the interspinous ligaments
-irreparable injuries to spinal cord accompany most severe flexion injuries of vertebral column

Question 8

fracture and dislocation of atlas

Answer 8

-vertical forces (striking the bottom of a pool) compressing the lateral masses between the occipital condyles and the axis drive from apart -> fracturing one or both anterior or posterior arches
-if significant -> rupture of transverse ligament that links the lateral masses will also occur -> Jefferson’ or burst fracture
-does not mean spinal cord injury bc the dimensions of the bony ring actually increase in size
-spinal cord injury more likely if transverse ligament has been ruptured

Question 9

dislocation of vertebrae: cervical

Answer 9

-bodies of cervical vertebrae can be dislocated in neck injury with less force than required to fracture
-slight dislocation can occur without damaging spinal cord due to large vertebral canal in cervical region -> severe may damage
-if dislocation does not result in facet humping with locking of the displaced articular processes -> cervical vertebrae may self reduce (slip back into place) > radiograph may not indicate cord has been injured!
-MRI may reveal resulting soft tissue damage
-severe hyperextension of neck (whiplash)- anterior longitudinal ligament is severely stretched and may be torn
-IV discs are centrally placed and extend to the anterior border of the IV foramen.
-herniating disc compresses the spinal nerve exiting at that level (cervical spinal nerves exit superior to the vertebra of the same number)
-Cervical disc protrusions result in pain in the neck, shoulder, arm, and hand.

Question 10

dislocation of vertebrae: thoracic and lumbar

Answer 10

-uncommon bc interlocking of their articular processes
-lumbar is more flexible than thoracic
-T11 and T12 are most commonly fractured noncervical vertebrae
-fractures of interarticular parts of vertebral laminae of L5 -> forward displacement of L5 vertebral body relative to sacrum (spondylolisthesis)
-spondylosis of L5 -> results from failure of the centrum of L5 to unite with neural arches during development
-spondylolisthesis at the L5-S1 articulation may result in pressure on the spinal nerve of the cauda equina as they pass into superior part of sacrum -> cause back and lower limb pain
-intrusion of L5 body into pelvic inlet reduces anteroposterior diameter of the pelvic inlet

Question 11

lumbar spinal stenosis

Answer 11

-stenotic (narrow) vertebral foramen in one or more lumbar vertebrae
-can cause compression of 1 or more spinal nerve roots occupying the vertebral canal
-surgical treatment- decompressive laminectomy
-can be hereditary
-can make you more vulnerable to age related degenerative changes like IV disc protrusion
-if IV disc protrusion occurs -> further compromises the size of the vertebral canal (so does arthritic proliferation and ligamentous degeneration)
-lumbar spinal nerves increase in size as vertebral column descends and IV foramina decrease in size

Question 12

vertebral body osteoporosis

Answer 12

-common metabolic bone disease
-net demineralization of bones caused by disruption of normal balance of calcium deposition and resorption
-quality of bone reduced and atrophy of skeletal tissue occurs
-neck of femur, bodies of vertebrae, metacarpals, and radius are most affected
-radiographs show diminished radiodensity of trabecular bone of the vertebral bodies -> Cause thinned cortical bone to appear relatively prominent
-especially affects horizontal trabeculae of trabecular bone of the vertebral body
-vertical striping may become apparent -> reflecting loss of horizontal supporting trabeculae and thickening of the vertical struts
-radiographs in later stages show vertebral collapse (compression fracture) and increased thoracic kyphosis
-vertebral body osteoporosis occurs in all vertebrae but is most common in thoracic and postmenopausal women

Question 13

herniation of nucleus pulposus

Answer 13

-herniation into or through anulus fibrosus causes low back and lower limb pain
-degeneration of posterior longitudinal ligament and wearing of anulus fibrosus -> nucleus pulposus may herniate into vertebral canal and compress the spinal cord or nerve roots of spinal nerves in cauda equina
-herniations usually occur posterolaterally -> where anulus is thin and dose not receive support from the posterior or anterior longitudinal ligaments
-posterolateral herniation is more likely to be symptomatic bc of proximity of spinal nerve roots

Question 14

localized back pain: herniation

Answer 14

-results from pressure on longitudinal ligaments, periphery of the anulus fibrosus, and from local inflammation resulting from chemical irritation by substances from the ruptured nucleus pulposus
-generally muscular, joint, or fibroskeletal pain

Question 15

chronic pain: herniation

Answer 15

-spinal nerve roots being compressed by herniated disc ->referred to the area (dermatome) suppled by that nerve
-posterolateral herniation is most common in lumbar region
-in older pts, nerve root compression is likely due to increased ossification of the IV foramen as they exit

Question 16

sciatica

Answer 16

-caused by herniated lumbar IV disc or osteophytes that compress the L5 or S1 component of the sciatic nerve
-spinal nerve roots descend to the IV foramen and join to form the spinal nerve
-spinal nerve that exits a given IV foramen passes through the superior half of the foramen and lies above and is not affected by herniating disc
-nerve roots passing to the IV foramen immediately and farther below pass directly across the area of herniation

Question 17

rupture of transverse ligament of atlas

Answer 17

-dense is set free
-results in atlantoaxial subluxation (incomplete dislocation of the median atlantoaxial joint)
-when complete dislocation -> dens may be driven into upper cervical region of spinal cord -> quadriplegia or into the medulla of the brainstem -> death

Question 18

rupture of alar ligaments

Answer 18

-weaker than the transverse ligament of the atlas
-combined flexion and rotation of the head may tear one or both alar ligaments
-results in an increase 30% ROM to opposite side

Question 19

aging of vertebrae and intervertebral discs

Answer 19

-decrease in bone density and strength
-particularly in vertebral body -> results in superior and inferior surfaces becoming increasingly concave
-nuclei pulposi dehydrate and lose elastin and proteoglycans while gaining collagen
-IV discs lose their turgor -> Stiffer and more resistant to deformation
-lamellae of anulus thicken and often develop fissures and cavities
-IV disc increase in size with age
-compressive forces at the periphery of the vertebral bodies where the discs attach -> osteophytes (bony spurs) develop around

Question 20

injury and disease of zygapophysial joints

Answer 20

-related spinal nerves are often affected
-pain along the distribution pattern of the dermatomes and spasm in muscles derived from associated myotomes
-denervation of lumbar zygapophysial joints- procedure for pain relief caused by disease of these joints
-nerves are sectioned near the joints and destroyed by radiofrequency percutaneous rhizolysis (root dissolution)
-denervation directed at articular branches of 2 adjacent posterior rami bc each joint receives innervation from both the nerve exiting and the superjacent nerve
-generally associated with aging (osteoarthritis) or disease (rheumatoid arthritis)

Question 21

back pain

Answer 21

-5 categores of structures receive innervation in back and can be sources of pain:
-1. meninges- coverings of the spinal cord
-2. synovial joints- capsules of the zygapophysial joints
-3. muscles- intrinsic muscles of the back
-4. nervous tissue- spinal nerves or nerve roots exiting the IV foramina
-1&2 innervated by meningeal branches
-3&4 innervated by posterior rami
-pain from nervous tissue (compression or irritation of nerves)- referred pain- perceived as coming from skin (dermatome) suppled by that nerve

Question 22

fracture vs dislocation pain

Answer 22

-fracture- sharp -> periosteal origin
-dislocation- ligamentous
-acute localized pain associated with IV disc herniation -> disrupted posterolateral anulus fibrosis and impingement on the posterior longitudinal ligament
-pain in all of these latter instances is conveyed initially by the meningeal branches of the spinal nerves.

Question 23

muscular pain

Answer 23

-usually related to reflexive cramping (spasms) -> ischemia
-secondarily as a result of guarding- contraction of muscles in anticipation of pain

Question 24

ischemia of spinal cord

Answer 24

-segmental reinforcements of blood supply from the segmental medullary arteries supply blood to the anterior and posterior spinal arteries
-deficiency of blood supply (ischemia) to spinal cord -> affects function -> muscles weakness and paralysis
-caused by fractures, dislocations, drop in BP
-if segmental medullary arteries particularly great anterior segmental medullary artery are narrowed by obstructive arterial disease
-aorta can be purposely occlude (clamped) during surgery, aneurysm, or occlusion to great anterior segmental medullary artery -> may lose sensation and voluntary movement inferior to level of impaired blood supply -> paraplegia- secondary to death of neurons in part of spinal cord supplied by anterior spinal artery

Question 25

alternative circulation pathways

Answer 25

-vertebral venous plexuses can return blood from pelvis or abdomen to heart via superior vena cava if inferior vena cava is obstructed
-can also provide route for metastasis of cancer to vertebrae or brain from a abdominal or pelvic tumor (prostate cancer)

Question 26

lumbar spinal puncture

Answer 26

-needle inserted into subarachnoid space
-spinal tap
-pt leaning forward on side with back flexed
-spreads the laminae and spinous process apart, stretching the ligament flava
-inserted midline between the spinous processes of L3-L4 (or L4-L5)
-reduced danger of damaging spinal cord

Question 27

epidural

Answer 27

-injected into lumbar extradural (epidural) space
-direct effect on spinal nerve roots of the cauda equina after they exit from the dural sac
-loss of sensation inferior to level of the block
-anesthetic agent can also be injected into the extradural space in the sacral canal through sacral hiatus (causal epidural anesthesia) or through posterior sacral foramina (trans-sacral epidural anesthesia)

Question 28

back sprains

Answer 28

-only ligamentous tissue or the attachment of ligament t0 bone is involved without dislocation or fracture
-excessively strong contractions related to movements of the vertebral column -> excessive extension/rotation

Question 29

back strain

Answer 29

-involves some degree of stretching or microscopic tearing of muscle fibers
-muscles involved usually are those producing movements of lumbar IV joints
(erector spinae)
-if weight is not properly distributed -> strain
-most common cause of lower back pain
-using back as lever -> strain
-crouching, holding back straight, holding loads close to trunk, and using buttocks and lower limbs to assist with lifting

Question 30

back spasms

Answer 30

-result of muscle or ligament injury
-after performing an activity or movement that puts stress on back or herniated/ruptured disc, arthritis
-often sudden
-heavy lifting
-weak back and abdominal muscles
-as protective mechanism back muscles go into spams in response to inflammation following an injury
-sudden involuntary contraction of one or more muscle groups
-results in cramps, pain, interference with function, distorting of vertebral column

Question 31

straight leg test

Answer 31

-lasegue test/sign
-determines if pt with low back pain has herniated IV disc
-passively flex pts hip with the knee in full extension
-causes traction on the nerve root forming the sciatic nerve -> would cause pain if disc herniated

Question 32

54 year old man complains of lower back pain. States the pain radiates down the back of his right leg. He reports the pain increases when he cough or lifts objects; however, decreases if he lies down.

Answer 32

-sacral nerve plexus- S1
-laying down pressure relieved off the spine
-concern with kidneys

Question 33

22 year old man presents to the ED with atraumatic left calf pain radiating to his inner thigh which began 1 day prior. At time of presentation he denies no recent trauma, he denies lumbar bac, pain and denies lower extremity weakness. On physical examination he is an obese man, there is no calf erythema, edema, or tenderness to palpation. The right and left calves are symmetric in size. The lower extremity neurologic examination is normal and without sensory deficits.

Answer 33

-look at weight distribution- can he walk, how does he sit or stand
-myalgia- rx naproxen and cyclobenzaprine
-he returns 3 days later with symptom progress -> bilateral calf cramping and weakness, lower back pain, and complaints of numbness and tingling into his groin
-urinary incontinence
-marked lumbar sacral tenderness, + straight leg raise, inability to stand from sitting on stretcher, and unable to assess gait. + perianal anesthesia on rectal exam
-numbness and tingling into groin, urinary incontinence -> could be a neurologic emergency -> suspect spinal cord compression
-MRI is first choice but it is not available
-ultrasound- urinary retention
-CAT scan
-CT image findings revealed a large central disc osteophyte protrusion with multifactorial degenerative changes and congenitally short pedicles at L4-L5 resulting in suspected severe central canal stenosis and compression of the CE nerve roots. the bladder and bilateral cont…

Question 34

cauda equina syndrome

Answer 34

-collection of symptoms that include sciatica, saddle anesthesia, urinary retention, and sphincter dysfunction
-dx is achieved through physical exam and lumbar imaging
-True red flags -> early neurologic deficits-> prompt emergent lumbar spine imaging and neurosurgical consult
-familiarize self with uncharacteristic clinical presentations of CES -> unilateral lower extremity numbness and weakness without sphincter involvement or saddle anesthesia, -> help clinicians to recognize premonitory features of CES.
-without access to MRI -> CT scan should be obtained before transferring the patient.
-Consider CES when a patient presents with progressive neurologic deficits in the lower
extremities

Question 34

42 year old pt presents with pain in the shoulder and posterior lateral aspect of the upper extremity. Began 6 weeks ago spontaneously. Pain is associated with reported tingling sensation radiating into thumb and index finger of the right hand. Pt describes trouble sleeping and insomnia. Often sleep in recliner. OTC meds and physical therapy have no improved pain. Exam demonstrates slightly decreased biceps reflex of the right upper extremity as well as subtle decrease in strength.

Answer 34

-investigating cervical spine/nerves