Spine Flashcards
What injuries are most commonly associated with chance fractures?
Gastrointestinal injuries.
Criteria for burst fractures that can be treated non-operatively?
Neurologically intact and stable Less than 30 degrees of kyphosis (controversial) Less than 50% of vertebral height loss TLICS score 3 or less
Burst fractures that should be treated operatively.
Neurologic deficits with evidence of cord compression. Incomplete or complete cord injuries. Unstable injuries: TLICS 5 or greater, progressive kyphosis, PLC compromise, lamina fractures (controversial)
In general how many levels above and below should a burst fracture be instrumented.
One level above and one level below. Instrumentation should be under distraction.
Longer term complications of burst fractures?
Progressive kyphosis if PLC injury is unrecognized. Can lead to flat back deformity.
What is the boney morphology of a flexion teardrop fracture?
Large anterior lip fragments which distinguish it from an extension fracture. Also called quadrangular fractures.
Prognosis and treatment of most sub axial cervical burst fractures and flexion teardrop fractures?
Most are associated with spinal cord injuries.
Decompression and fusion.
In which arterial segment is the vertebral artery most vulnerable to traumatic injury?
V2 segment which is within the transverse foramina from C6-C1. Highest risk of injury is at the point of entry into the C6 foramen.
Which vertebral artery is usually dominant.
Left
How long after vertebral artery injury do complications occur?
Can be days to years following injury. Complications include: arteriovenous fistula, late-onset hemorrhage, pseudo aneurysm, thrombosis, cerebral ischemia/stroke, and death.
Indications for a CTA
There are many, any one of the following in a trauma patient is an indication: GCS<9 Unexplained central or materializing neurologic deficit. Evidence of acute cerebral infarct on CT scan of head. Diffuse axonal injury. Facial fracture or Le Fort type-II or III fracture. Cervical spine fracture of C1, 2, or 3 or fracture extension into transverse foramen. spinal cord injury hanging injuries major thoracic injury or first-rib fracture.
Removal of cervical collar without radiographic studies allowed if?
Patient is awake, alert, and not intoxicated. Has no neck pain, tenderness, or neurologic deficits. Has no distracting injuries.
When must radiographic cervical spine clearance be obtained?
Intoxicated or altered mental status. Neck pain or tenderness. Distracting injury.
What constitutes adequate radiographic cervical spine trauma imaging?
Cervical spine radiographic series: AP, Lateral, open-mouth odontoid view. CT scan. All imaging must include top of T1 vertebra
What are the complications associated with delayed c-spine clearance?
Increased risk of aspiration. Inhibition of respiratory function. Decubitus ulcers (occipital and submandibular areas. Possible increase in intracranial pressure.
What is the most common incomplete spinal cord injury?
Central cord syndrome.
What does sacral sparing mean when determining complete vs incomplete injury?
Sacral sparing best determined by the presence of VOLUNTARY ANAL CONTRACTION. If they have sacral sparing should also have intact perianal sensation. Need to differentiate this from bulbocavernosus reflex.
How do you determine neurologic level of injury?
Lowest segment with intact sensation and antigravity muscle function strength. In regions where there is no myotome to test, the motor level is presumed to be the same as the sensory level.
ASIA B
No motor function below the neurologic level. By definition must have preserved sensation.
ASIA C
Motor function is preserved below neurologic level- more than half of key muscles below the neurological level have a muscle GRADE LESS THAN 3.
ASIA D
Motor function is preserved below neurologic level- more than half of key muscles below the neurological level have a muscle GRADE OF 3 OR MORE.
What injuries can lead to complete loss of bulbocavernous reflex?
Conus and cauda equina injuries.
When should corticosteroids be given in the trauma patient with spinal injury?
Literature does not support it being given at any time.
When is systemic and or local hypothermia recommended for spinal cord injuries?
Not recommended. Can see the following complications: coagulopathy, sepsis, pneumonia, arrhythmias, and rebound hypertension.
When should decompression be performed for a complete spinal cord injury? Incomplete spinal cord injury? What recovery could this facilitate?
within 24 hrs within 24 hrs may facilitate nerve root function at level of injury (1-2 levels).
When should GSW of the spine undergo operative intervention?
Progressive neurological deterioration with retained bullet within the spinal canal. Cauda equina syndrome (treated like a peripheral nerve) Retained bullet or fragement within the thecal sac (CSF can breakdown of lead causing lead poisoning)
What is autonomic dysreflexia?
An increase in systolic blood pressure of at least 20% associated with a change in heart rate and accompanied by at least one of the following signs or symptoms: Signs: sweating, piloerection, facial flushing Symptoms: headache, blurred vision, stuffy nose This is all due to a stimulus such as over distended bladder or bowel impaction that can be seen in spinal cord injury patients.
Other causes include occult infections, skin irritation, decubitus ulcers, or lower extremity fractures.
What can loss of supra-spinal control of the sympathetic nervous system in spinal cord injury patients with lesions at T6 or higher lead to?
Both supine and orthostatic hypotension. Cardiac arrhythmias. Autonomic dysreflexia.
Does conus medullaris syndrome have a better or worse prognosis for recovery than a more proximal lesion.
Better.
What percent of complete spinal cord injuries can expect an improvement of one nerve root level? Two nerve root levels? Complete recovery?
80% 20% 1%
What are some trends of improvement in incomplete spinal cord injuries?
The greater the sparring the greater the recovery. Patients that show more rapid recovery have a better prognosis. When recovery plateaus it rarely resumes improvement.
What function would you expect for a spinal cord injury with a C1-C3 level?
Ventilator dependent, limited talking, electric wheelchair with head or chin control.
What function would you expect for a spinal cord injury with a C3-C4 level?
Initially ventilator dependent, but can become independent. Electric wheelchair with head or chin control.
What function would you expect for a spinal cord injury with a C5 level?
Ventilator independent. Cannot feed oneself because of lack of wrist extension and supination. Electric wheelchair with hand controls. Can achieve independent ADLs with assistive devices.
What function would you expect for a spinal cord injury with a C6 level?
Manual wheelchair. Independent living. Can drive a car with manual controls. Sliding board transfers. Much better function than C5.
What function would you expect for a spinal cord injury with a C7 level?
Daily use of a manual wheelchair with independent transfers.
What function would you expect for a spinal cord injury with a C8-T1 level?
Improved hand and finger strength and dexterity. Expected to be fully independent.
What are the descending tracts of the spinal cord?
Motor: lateral corticospinal tract and ventral corticospinal tract.
What are the ascending tracts of the spinal cord?
Sensory: Dorsal columns- deep touch, vibration, and proprioception Lateral spinothalamic tract- pain and temperature Ventral spinothalamic tract- light touch
What is hyperpathia
Burning in distal upper extremity. Seen in central cord syndrome.
Where is weakness worst in central cord syndrome?
Upper extremities affected more than lower extremities. Hands affected more than more proximal areas of UE. Represents selective injury to central areas of LCT.
What is injured and what is preserved in anterior cord syndrome?
LCT and LST are injured. Loss of pain and temperature. Motor loss with lower extremities affected more. DC (proprioception, vibratory sense) is preserved.
What is the prognosis of anterior cord syndrome?
worst prognosis of incomplete cord injuries. 10-20% chance of motor recover. Often mimics central cord syndrome.
What is Brown-Sequard Syndrome?
Ipsilateral deficit in motor function (LCS) and dorsal columns (proprioception and vibratory sense) Contralateral deficit pain and temperature (LST, remember this tract classically crosses two levels below) Usually seen with penetration trauma.
What is the prognosis of Brown-Sequard Syndrome?
excellent prognosis 99% ambulatory at final follow-up Best prognosis for functional motor activity of incomplete cord injuries.
What is the Anderson and Montesano Classification?
For Occipital Condyle fractures Type 1 Compression. Comminution of occipital condyle. Stable injury. Type 2 direct blow. Basilar skull fracture that extends into one or both occipital condyles. Usually stable injury. Type 3 rotation/lateral bending. Avulsion fracture of condyle in the region of the alar ligament. Potentially unstable. Suspect occipitocervical dissociation.
What is the primary stabilizer of the atlantoaxial junction?
Transverse ligament.
What are the intrinsic ligaments of the Craniocervical junction (CCJ) or occipitoatlantoaxial complex?
Transverse ligament Alar ligaments Apical ligament Tectorial membrane
Where does the transverse ligament of the CCJ attach?
posterior odontoid to anterior atlas arch.
Where do the alar ligaments attach?
Odontoid to occipital condyles.
Where does the apical ligament attach?
vertically from odontoid to foramen magnum.
What is and where does the tectorial membrane travel?
cephalic continuation of the PLL connects posterior body of axis to anterior foramen magnum.
What neurologic deficits are often seen with condyle fractures and craniocervical injuries?
Lower cranial nerve deficits. Most often CN 9,10, and 11.
When are occipital condyle fractures treated operatively?How are they treated?
Type 3 with obvious instability or any neural compression from a fracture fragment. Occiput to C2/C3 fusion.
Degenerative causes of atlantoaxial instability?
Down’s syndrome. Rheumatoid arthritis. Os odontoideum.
Traumatic causes of atlantoaxial instability?
Atlas fracture. Transverse ligament injury Type 1 Odontoid fracture.
Pediatric causes of atlantoaxial instability?
JRA Morquio’s Syndrome trauma/infection leading to rotatory atlantoaxial subluxation.
What percent of rotation does the C1-C2 joint provide?
50%
How many mm on sum of lateral mass displacement is predictive of a transverse ligament rupture?
>7mm
> 8.1mm with radiographic magnification
In an adult without RA what atlanta-dens interval (ADI) is considered normal, stable injury to transverse ligament, and unstable injury?
Normal <3mm (<5mm in a child)
3-5mm Distance between posterior border of anterior arch of C1 and odontoid.
>5mm suggests injury to transverse ligament as well as alar ligament, and tectorial membrane.
What is the risk of neurologic injury with atlas fractures and transverse ligament injuries? Associated injuries?
Low. 50% have an associated spine injury. 40% have associated axis fx.
What is a common anatomic variation of C1?
incomplete formation of the posterior arch
Describe Landells Atlas Fracture Classification
When is a Jefferson Fracture Treated operatively?
In general when there is a intrasubstance tear of the transverse ligament, but even then it is controversial.
All types of Jefferson fractures can be treated with a hard collar or halo for 6-12 weeks.
What can appear like a type II odontoid fx on x-ray?
How should it be treated?
Os odontoideum
Treatment is observations.
How many ossification centers does the axis have and when do they fuse?
Five ossification ceners.
between the dens and vertebral body that does not fuse until 6 yrs.
Secondary ossification center towards the tip of the dens. Doesn’t appear until 3 yrs and fuses at age 12.
What is the blood supply to the odontoid?
Apex is supplied by branches of internal carotid artery.
Base is supplies from branches of vertebral artery.
Limited blood supply in the watershed area between the apex and the base.
What is the normal ROM for the cervical spine?
What articulartion accout for the majority of the motion?
100 degrees rotation, 110 degrees of flexion/extension, and 68 degrees of lateral bend.
C1-C2: 50r, 50f/e, and 0 lateral bend
C2-C3: 50r, 50f/e, and 60 lateral bend.
What is a type I odontoid fracture?
Oblique avulsion fs of tip of odontoid due to avulsion of alar ligament.
Should rule out atlantooccipital instability with flex/ext views.
What fracture can be treated with an anterior odonoid screw?
Posterior inferior to anterior superior fracture line. The opposite needs posterior fixation.
How should Type III odontoid fractures be treated if no instability?
Hard collar. No evidence to suggest halo is better.
What are risk factors for Type II odontoid fracture non-unions?
>= 6mm displacement. Biggest reason to consider surgery
age > 50 yrs
fx comminution
smoker
fracture gap > 1mm
Angulation > 10 degrees
What is the major pro and con to anterior odontoid screw osteosynthesis?
Pro is preservation of atlantoaxial motion.
Con is higher failure rate than posterior C1-C2 fusion.
What percentage of people over the age of 65 show spondylotic changes regardless of symptomoatology?
85%
Which levels are most associated with spondylosis?
C5-C6 > C6-7.
Because these levels are associated with the most flexion and extension in the subaxial spine.
What makes up the cervical motion segment?
Intervertebral disc
two facet joints
two uncovertebral joints of luschka
Normal cervical canal diameter?
At what diameter are you considered to have central stenosis?
17mm
13mm
What causes nerve root irritation besides direct compression?
Chemical pain mediators: IL-1, IL-6, substance P, bradykinin, TNF alpha, prostaglandins.
What can be caused by a C4 radiculopathy?
Scapular winging
True or false cervical radiculopathy is often global and nondermatomal pain radiating down arm.
True
What percent of patients with cervical radiculopathy improve with non-operative management?
75%
What is an ideal indication for a posterior foraminotomy?
Soft foraminal disc herniation causing single level radiculopathy is most ideal.
Can olso be used for osteophytic foraminal narrowing.
What percent of patients can expect long term relief from a selective nerve root corticosteroid injection?
40-70%
What is the indication for cervical total disc replacement?
Single level disease with minimal arthrosis of the facets.
What are the pros and cons of a posterior foraminotomy?
Pros: avoids need for fusion, avoids problems associated with anterior procedure such as dysphagia.
Cons: More difficult to remove discosteophyte complex and disc height can not be restored.
What is the risk of pseudoarthrosis for ACDF?
How should revision surgery be performed?
Which has a higher fusion rate?
5-10% for single level. 30% for multilevel fusions
Can be either posterior or anterior, but should be anterior if persistent radiculopathy.
Posterior has higher fusion rate, but higher rate of complications.
What is the most common nerve injured during ACDF?
What is the risk?
Recurrent laryngeal nerve.
1% risk
Literature has not shown a right or left approach to have greater risk.
What is the recommended treatment for a recurrent laryngeal nerve injury?
6 weeks of observation
If still persisting then ENT consult for scope and teflon injection.
Where is the sympathetic chain found when performing ACDF surgery?
lateral border of longus coli muscle at C6.
What is a risk of anterior approached for the upper cervical spine?
hypoglossal nerve injury.
tongue will deviate to the side of the injury.
Which levels have higher risk of dysphagia in anterior cervical surgery?
upper levels, especially C3-C4.
What is a Hangman’s Fracture?
What is the mechanism?
traumatic anterior spondylolithesis of the axis due to bilateral fracture of pars interarticularis.
Hyperextension with secondary flexion.
True or false patients are usually neurologically intact after a traumatic spondylolisthesis of the axis?
True
Describe Levine and Edwards Classification of Hangman’s fractures.
Which facet in the cervical spine is most often fractured?
Superior facet.
What is the most frequently missed cervical spine injury on plain x-rays?
unilateral facet dislocation.
How much subluxation will you see with a unilateral facet dislocation?
How much for bilateral facet dislocation?
25%
50%
Where do the majoirty of facet dislocations occur?
Most occur within the subaxial spine (C3-C7).
75% of the time.
In a patient with a facet dislocation, what might loss of disc height indicate?
retropulsed disc in canal.
When can you consider performing a closed reduction in a patient without an MRI?
Patient with facet dislocion and deficits but no mental status changes.
They must be awake and cooperative.
What is the mechanism of lateral mass fracture separation?
Hyperextesion, lateral compression, and rotation.
Uncommon injury chracterized by a high degree of instability.
Usually has neurological deficit (66% of the time).
What is the success rate of non-operative treatment of lateral mass separation fractures?
less desirable.
Spontaneous fusion rate is only 20%
What is the perfered method of treatment for a lateral mass separation fracture?
Two level fusion via a posterior approach.
What time period is considered early decompression and has been show to improve neurologic outcomes?
Less than 24 hrs.
What is a clay-shovelers fracture?
Cervical spinous process fracture. Most commonly at C7.
Can affect C6 to T3.
How many pounds of force are Mayfield pints tightened to?
60 lbs
How tight should Gardner-Wells tongs be?
Until sping indicator is 1mm above the surface.
This is equivalent to 139 Newtons or 31 lbs of force.
overtightening by .3mm leads to 448 newtons or 100lbs.
What is the reduction maneuver for a unilateral facet dislocation?
Add weight in 10 lb increments every 20 minutes.
Reduction maneuver performed once the facet is perched.
Maintain axial load and rotate the head 30-40 degrees past midline in the direction of the dislocation.
Stop once resistance is felt.
Reduction maneuver for bilateral facet dislocation?
Add weight until in a perched position then apply an anterior directed force caudal to the level of the dislocation.
Rotate the head 40 degrees in each direction while axial traction is maintained.
Which motion is the Halo vest most effective at controlling?
atlantoaxial rotation.
Not very good for controlling motion in the subaxial spine.
What are absolute contraindications to Halow Vest?
Cranial fractures.
Infection.
Severe soft-tissue injury in the region of the vest.
What are relative contraindications to halo vests?
polytrauma.
severe chest trauma.
barrel-shaped chest.
obesity.
advanced age (recent evidence demonstrates an unacceptably high mortality rate in patients aged 79 years and older (21%).
What should be done in kids younger than 10 before applying a halo?
Need to get a CT scan to determine the thickness of the skull.
What is the safe zone for anterior halo pins?
What structures does this avoid?
1cm region just above the lateral one third of the eybrow at or below the equator of the skull.
This places the pin lateral to the supraorbital nerve and anterior and medial to temporalis fossa and muscle.
How many pins and inch-pounds of torque for an adult Halo?
4 pins at 8 inch-pounds
How many pins and inch-pounds for a pediatric halo?
6-8 pins
2-4 inch-pounds.
Children < 2yrs should use a Minerva cast.
What is the most common complication of Halo vests?
How should it be treated?
Loosening (36% of complications)
retightening if unsuccesful or continues to loosen pin exchange.
What do you do if a patient has a pin sight infection of their halo?
oral antibiotics if not loose.
If loose the pi should be removed.
What cranial nerve is most commonly injured with a halo?
Abducens nerve palsy.
Thought to be a traction injury.
Loss of lateral gaze on the affected side.
Where do fracture dislocations of the spine most often occur?
What is the most common mechanism?
thoracolumbar junction.
motor vehicle accident.
What is defined as the lumbothoracic junction?
T10-L2
Area of high mobility next to an area of lower mobility creats an area vulnerable to shearing forces.
True of false the level of neurological deficit does not align with apparent level of spinal injury on a MRI?
True
Describe the TLICS system.
What is the most common fragility fracture?
Vertebral compression fracture.
Affects 25% of people over 70 yrs.
Affects 50% of people over 80 yrs.
What is the strongest predictor of future vertebral fractures in postmenopausal women?
history of 2 VCFs.
How does the 1 yr mortality rates after a vertebral compression fracture compare to a hip fx?
What about at 2 yrs?
15% which is less than a hip fx (25%)
Equal.
What is an associated condition with vertebral compression fractures that can lead to increased mortality?
Increasing kyphosis that leads to reduced pulmonary function.
What sign on MRI is suggestive of an osteoporotic vertebral compression fracture and not another process?
fluid sign.
What is the risk of a concomitant spine fracture when one vertebral compression fracture is found?
20%
Consider obtaining radiographs of the entire spine.
What should be on your differential for a vertebral compression fracture?
Malignancy. Should be suspicious of fractures above T5, atypical radiographs, constitutional symptoms, and younger patients with no hx of trauma.
Should obtain CBC, BMP, inflammatory labs, and urine and serum protein electrophoresis if concerned of another process.
What medication can be given in acute fractures(within 5 days) to decrease pain?
How long can it be given?
Calcitonin.
4 weeks.
What is the AAOS recomendation on vertebroplasty?
Recommends strongly against.
What is the AAOS recommendation for kyphoplasty?
Limited recommendation strength.
Consider in patients with severe pain after 6 weeks of non-operative treatment.
cavity is created by a ballon so that cement can be injected with left pressure.
What is the most sensitive test for myelopathy?
Hoffman sign, found to be 59% sensitive while upward babinski and clonus were 13%.
What are causes of myelopathy other than spinal stenosis?
MS, ALS, multifocal motor neuropathy, and Guillain-Barre’s Syndrome.
When can the superior laryngeal nerve be injured in spine surgery?
Anterior cervical surgery between C2-C3.
Innervates a portion of the larynx (cricothyroid muscles) and vocal cords.
Modulates voice pitch and explosive sounds.
What are they symptoms of a recurrent laryngeal nerve injury?
hoarseness occurs in 3-11%. Permanent in .33%
Because many people become asymptomatic should have the vocal cords evaluated pre-operatively.
Do not want to operate on the opposite side of an existing vocal cord injury.
How much should an adult isthmic spondylolisthesis be reduced?
Petraco et al showed that L5 nerve injury is not linear with 71% of strain occuring in the second half of reduction.
Partial reduction may be safer than complete reduction for high grade spondylolisthesis.
What patient is most likley to have a pelvic fracture?
Elderly women.
True or false unilateral preservation of sacral nerves is not adequate for bowel and bladder control?
False, they are usually adequate.
Which x-ray provides the best assessment of sacral spinal canal?
Inlet view.
Which Denis zone fracture may be amenable to sacroplasty?
Zone 1 but cannot be displaced which risks symptomatic cement leakage.
What are the common forms of spinal cord monitoring?
EMG
SEP
MEP
What areas of the spinal cord is monitored by SEPs?
Dorsal column sensory pathways.
Where is signal initiation and recording with SEPs?
Signal initiation in lower extremity usually involves posterior tibial nerve. Upper extremity ulnar nerve.
Signal recording is transcranial from somatosensory cortex.
What is a disadvantages of SEPs?
Not reliable for monitoring the integirty of the naterior spinal cord pathways.
What is an advantage of MEPs?
effective at detecting an ischemic injury in anterior 2/3 of spinal cord.
What is a disadvantage of MEPs for spinal cord monitoring?
unreliable due to effects of anesthesia.
What is the difference and significance of “burst activity” and “sustained train” during mechanical electromyography?
Burst activity occurs with contact of a surgical instrument with a nerve root. Not due to an injury and not clinically significant.
Sustained train occurs with traction or significatn injury to a nerve root which may be clinically signficiant.
Advantage and disadvantage of mechanical electromyography?
Advantage- allows monitoring of specific nerve roots.
Disadvantage- overly sensitive. Sustained train does not always refelct nerve root injury.
How does electrical electromyography work for monitoring pedicle screw placement?
Bone conducts electricity poorly so only if a pedicle screw is breached will stimulation of a pedicle screw lead to activity of a specific nerve root.
Most common pathogen to cause of vertebral osteomyelitis or spondylodiskitis?
What is the second most common cause?
staph aureus (50-65% of the time).
staph epidermidis.
What pathogen other than staph aurues and staph epidermidis is associated with vertebral osteomyelitis and IV drug use?
pseudomonas.
True or false disc destruction is atypical of neoplasms?
True.
How often is fever present in vertebral osteomyelitis?
only 1/3 of the time.
Which inflammatory marker is more reliable for tracking the success of treatment of vertebral osteomyelitis?
CRP.
How often are blood cultures positive in patients with spondylodiskitis?
When positive how accurate are they for isolating the correct ogranism?
33% (reports from 25%-66%)
85%
What two findings on imaging support vertebral osteomyelitis over malignancy?
Disc space involvement.
End-plate erosion.
What is the most important prognostic indicator of clinical outcome in patients with epidural abscess?
preoperative degree of neurologic deficit.
Where are epidural abscesses most commonly located within the spine?
dorally in the thoracolumbar spine.
When can medical treatment of epidural abscess be effective?
What factors are associated with failure of medical treatment?
small abscesses with no neurologic deficits.
Diabetes, CRP >115mg/L, WBC> 12k/ml
Positive blood cultures, age >65 years, and MRSA.
Why is diskitis more common in pediatric patients than adults?
In children the blood vessels extend from the cartilaginous end plate into the nucleus pulpossus allowing direct innoculation. In adults it only extends to the annulus fibrosis.
What may be the earliest radiographic sign of discits in a child?
Loss of lumbar lordosis.
What must be ruled out if a patient with discitis is not getting better with antibiotic treatment?
Rule out TB.
Is TB becoming more or less common in the United States?
more common due to increasing immunocompromised population.
What is the most common extrapulmonary site for TB?
thoracic spine.
5% of all TB patients have spine involvement.
What two things are characteristic of early TB infection of the spine?
Large paraspinal abscess formation (Seen 50% of the time, usually anterior, more common than pyogenic infections).
Initially does not involve the disc space, can lead to it being misdiagnoses as a neoplastic lesion.
What is a finding of chronic TB infections of the spine?
kyphosis.
Adults it usually stays static with healing.
In childens it progresses 40% of the time with healing.
True or false back pain is a late finding of tuberculous spondylitis?
True.
What should tuberculin spine infections be tested for?
acid fast bacilli.
Can take 10 weeks to grow in cultures
PCR allows for faster identification.
What are other etiologies of granulomatous infection of the spine that may have similar clinical picture as TB?
Atypical bacteria: Actinomyces israelii, Nocardia asteroids, Brucella.
Fungi: Coccidioides immitis, Blastomyces dermatitidis, Cryptococcus neofromans, and Aspergillosis.
Spirochetes: Treponema pallidum.
What medication regimen should be used for Tuberculosis spinal infections?
RHZE for 2 months
RH for 9 to 18 months
R-rifampin
H-isoniazid
E-ethambutol
Z-pyrazanamide
What is the most common cause and type of peripheral nerve injury detected by electrophysiologic monitoring during anterior cervical spine surgery?
Brachial plexopathy following shoulder taping and application of countertraction.
What was associated with use of morphine nerve paste applied to the dura after spinal decompression?
epidemic levels of surgical site infections.
In addition to deferentiating peripheral nerve compression from radiculopathy what else are electrodiagnostic studies usefule for detectiong?
systemic neurologic disorders such as ALS.
Laminoplasty is contraindicated in?
setting of fixed kyphosis.
What percentage of asymptomatic patients over the age of 40 will have findings of HNP or foraminal stenosis on cervical MRI?
25%
Which factor has been associated with worse patient-reported outcomes for those undergoing surgical correction of adult spinal deformity? Obesity/Advanced Age/Pre-operative disability scores?
Obesity.
Age is associated with more complications but not worse patient reported outcomes.
How should a patient be treated with a GSW that has penetrated both spinal canal and abdomen with the projectile retained in the vertebral body?
Do not need to remove the projectile.
Broad spectrum IV abx for 7-14 days because of bowel contamination.
Who is a good candidate for laminoplaty?
Multilevel cercial myelopathy with preserved cervical lordosis.
No kyphosis
No Axial neck pain
Congenital cervical stenosis often ideal.
What is a positive predictor of return to play in professional atheletes after lumbar disc herniation?
Higher number of games played prior to injury.
Age was associated with a worse prognosis.
What is powers ratio.
Used to determine if there is occipitocervical instability.
Seen in patients with down syndrome.
How do you calculate Torg-Pavlov ratio?
What is a normal value?
canal/vertebral body width
< .8 is abnormal. 1 is normal.
Torg <.8 is not a contraindication of return to play.
Describe the Oswestry Disability Index (ODI)
Useful for all conditions that affect low back pain.
Considered the gold standarp of low back functional outcome tools.
What is the mJOA outcome measure?
Japanese Orthopaedic Association for the evaluation of operative results in patients with cercial myelopathy.
A point scoring system (17 total) based on function in the following categories:
Upper extremity motor function
Lower extremity motor function
Sensory function
Bladder function
Briefly describe Tokuhashi Score?
Prognostic score based on 6 elements:
general condition, extraspinal bony metastasis, number of vertebral bodies with metastasis, visceral metastasis, primary tumor, neurolgoic compromise.
Socre of 0-8: <6 months; 9-12 6-12 months; 12-15 > 1 year.
What is the NOMS framework when considering treatment of metastatic lesion of the spine?
Neurolgoic: measure of epidrual spinal cord compression (ESCC) 0-1 low grade. 2-3 high grade
Oncologic: responsiveness to radiation
Mechanical instability: spinal instability neoplastic score (SINS). See other side of card for description.
0-6 no surgical consultation required, 7-18 surgical consultation advisable.
Systemic illness: formulation of prognosis fromdisease burden, medical comorbidities, and functional status. Can use Eastern Cooperative Oncology Group’s Performance Status Rating (ECOG-PSR)
How does spinal canal diameter and spinal dord diameter vary within the thoracic spine?
Endplate area?
See image for spinal canal and cord dimenesions.
Endplate area progressively increases from T1 to T12.
Describe Thoracic Pedicle Anatomy as it refers to:
Diameter
Length
Angle
Diameter: Pedicle wall is twice as thick medially as laterally.
On average T4 is most narrow. T12 is the largest and is usually larger than L1.
Length: decreses from T1 to T4 and then increases agian as you move distal in the thoracic spine. T1 20mm. T4 14mm T10 back to 20mm
Angle: transverse ange varies from 5 degrees Lateral at T12 to 25 degrees medial at T1. See image.
Sagittal pedicle angle is depicted on the previous page. It is 15-17 degrees cephalad for the majority of thoracic spine.
What are the erector spinae muscles from medial to lateral?
Spinalis- spinous process to spinous process
Longissimus- transverse process to transverse process
Iliocostalis- Origin on ilium and ribs that inserts on ribs and transverse processes.
Innervated by dorsal rami of spinal nerves.
For Rheumatoid patients what is the mechanism of basilar invagination?
How often is it present?
What radiographic lines are used to evaluate its presence, severity, and progression.
Treatment?
Cranial migration of dens from erosion and bone loss between occiput and C1 and C2.
Present in 40% of RA patients
Often seen in combination with fixed atlantoaxial subluxation.
C2 to occiput fusion- progressive cranial migration (>5 mm), neurologic compromise, and cervicomedullary angle <135 on MRI.
What is the cause of OPLL?
What are associated factors?
Cause is unclear. Multifactorial
Diabetes, obesity, high salt-low meat diet, poor calcium absorption, and mechanical stress on posterior longitudinal ligament.
What are some of the classification systems for myelopathy?
Nurick Classification
Ranawat Classification
Japanese Orthopaedic Association Classification
How do you measure the C2-C7 alignment angle?
How do you measure the local kyphosis angle?
C2-C7: determined by tengential lines on the posterior edge of the C2 and C7 body on lateral radiographs in neutral position.
Local kyphosis angle- the angle between the lines drawn at the posterior margin of most cranial and caudal vertebral bodies forming the maximum local kyphosis
What is the cord compression ratio?
What value portends a poorer prognosis?
Compression ratio = smalles AP diameter of cord / largest transverse diameter of cord.
compression ratio < .4 carries poor prognosis.
What amount of fixed kyphosis is a contraindication to cervical laminectomy and fusion?
>10 degrees
will not adequately decompress spinal cord as it is “bowstrining: anteriorly.
True or false: the facets become more coronal as you move inferiorly in the Lumbar spine?
What happens to the pedicles?
True.
Angulate more medial as you move distal
L1: 12 degrees
L5: 30 degrees
S1: 39 degrees
L1 has the smalles pedicle diamter in the Lumbar spine.
How do you calculate Pelvic Incidence, pelvic tilt, and sacral slope?
Pelvic Incidence = pelvic tilt + sacral slope
Pelvic tilt = pelvic incidence- sacral slope
Sacral slope = pelvic incidence - pelvic tilt
What are the key features of Cauda equina syndrome?
Back pain.
Bilateral leg pain
bowel and bladder dysfunction (complete incontinence is more consistent). Urinary retention and eventually overflow incontinence.
Decreased rectal tone.
Bowel dysfunction is rare.
Saddle anestheisa (loss of sensation in genitalia most consistent)
Lower extremity sensorimotor changes.
Describe a pedicle-to-pedicle decompression of the lumbar spine.
What is a cortical bone trajectory screw?
What are the proposed advantages?
A srew that is designed to decrease the amount of lateral exposure for obtaining screw starting points.
Starting point is more medial and caudal.
Trajectory is more cephalad.
Advantages of lower blood loss, skin incision, and pain scores 1-week post-op.
Similar fusion rates and functional outcomes longterm.
controversy over which provides better fixation.
What is the Wiltse Newman Classification in spine used for?
Classification of spondylolisthesis.
What will you see on radiographs of a patient with Ankylosing spondylitis?
Squaring of vertebrae with vertical or marginal syndesmophytes.
Late vertebral scalloping (bamboo spine)
Will see bilateral symmetric sacroiliac erosion. Earliest finding is erosion of the iliac side.
Ferguson pelvic tilt view allows for improved visualization of anterior SI joint. xray beam directed 10 to 15 degrees cephalad.
50% of radiographs miss fractures in AS. acute pain is concerning for fracture. CT scan is most sensitive. MRIbest for looking for epidural hemorrhage.
What are Romanus lesions?
“shiny corners” at attachement of annulus fibrosus
seen in ankylosing spondylitis.
How should the following injury be treated?
Patient has ankylosing spondylitis.
Should be treated with posterior fusion.
In general instrument 3 levels above and 3 levels below.
How is scoliosis in the coronal plane measured?
Cobb angle
Coronal balance can be measured by using C7 plumb line (C7PL) and center sacral vertical line (CSVL) see image
What does this image depict most likely if it is from a teenage football player with an insidious onsent of back pain?
spondylolysis can often present as sclerosis as seen in the previous image not just defects as seen on the image below.
On a cross table lateral of a pediatric cervical spine, which of these are normal findings:
prevertebral swelling > 2/3 of adjacent vertebral width?
retropharyngeal space <6 mm at C2 and <22 mm at C6?
Retrotracheal space <16mm?
7 year old with ADI of 4mm?
Vertebral body wedging?
Loss of cervical lordosis?
C3-C4 subluxation of 3mm?
Not normal- prevertebral swelling should be < 2/3 of adjacent vertebral width
Normal- retropharyngeal space < 6mm at C2 and < 22mm at C6.
Not normal- retrotracheal space should be < 14mm
Normal- ADI < 5mm in childen and < 3mm in adolescents
Normal- 7% of noral children will have wedge shaped vertebral body, usually at C3.
Normal to hav eloss of cervical lordosis
Normal- Can have C2-C3 or C3-C4 pseudosubluxation < 4mm as long as the posterio laminar line is smooth and contiguous.
What is the gold standar for diagnosis of atlantoaxial rotatory displacement?
Dynamic CT is the gold standard.
Take the CT with head stright forward and then in maximal rotation to right and left.
Will see fixed rotation of C1 and C2 which does not change with dynamic rotation.
What is the treatment for atlantoaxial rotatory displacement?
What are the associated conditions with juvenile idiopathic scoliosis?
syringomyelia
Arnold-Chiari syndrome: cerebellar tonsils are elongated and protruding through the opening of the base of the skull and blocking CSF flow.
Tethered cord
dysraphism (incomplete fusion)
spinal cord tumor
What are the different rib phases in infantile idiopathic scoliosis?
Phase 1: usually resolves. No overlap of rib and vertebral body.
Phase 2: Progressive. Rib on convex side overlaps the vertebral body.
How do you measure the Mehta angle?
Also known as rib vertebrae angle difference or RVAD
> 20 degrees is linked to high rate of progression
<20 is associated with spontaneous recovery.
What is the risk of pregression of congenital scoliosis?
Determined by the morphology of the vertebrae.
Greatest rate of progression with unilateral unsegmented bar with contralateral hemivertebra. Potential to progress 5 to 10 degrees/year
Least risk of progression is block vertebrae. progress <2 degrees/year.
Most rapid progression in the first 3 years of life.
anterior failure of formation is rapidly progressive and often results in paralysis.
Presence of fuse ribs increases risk of progression.
For the following diseases that lead to neuromuscular scoliosis describe the recommended nonoperative and operative treatments.
How would you treat a patient with cerebral plasy who is 12 years old, has a 70 degree curve with 10 degrees of pelvic obliquity and ambulates? What if they didn’t ambulate?
How about a patient with a Group II curve that ambulates?
PSF without extension to pelvis
PSF with extension to pelvis +/- anterior fusion
PSF with extension to pelvis +/- anterior fusion
What preoperative assessment and work-up should be done in a patient with cerebral palsy that has scoliosis and is going to undergo operative fixation?
What treatment is recommended for Scheuermann’s Kyphosis?
In pediatric patients with high grade isthmic spondylolisthesis what radiographic measurement is most predictive of progression?
What measurement is most predictive on severity of disease?
Slip angle for progression
Pelvic incidence for severity of disease.
