Spine Flashcards
proximal extent of fusion for Scheurmans
span the whole deformity
what is sagittal vertical axis
plumb line from C7 to fall BEHIND hips and within 4-5cm of posterior corner of S1
relationship of pelvic incidence to lumbar lordosis
generally PI is within 10 deg of lumbar lordosis
TLSO is most effective for which curves
those with apex BELOW t7
delay in diagnosis of 3 column spine injuries in pts with anklyosed spine
up to 19% of cases
tx of frx dislocation of spine
posterior reduction, stabilization 2 levels above and below
risk factors for PJK
adv age, 360 fusions; fusion to sacrum; upper instrumentation ending at T1-T3
trigger EMG thresholds
< 4-6mA means intact with neural structure; > 10 is safe; 9-10 is pedicle breach
what is effect of inhaled anesthetic vs IV anesthetic on neuromonitoring
inhaled dampens neuro physio signals
what is benefit of recombinant PTH for vertebral frx
reduced by 65%
effect of bisphos on vertebral frx
reduces by 50-70%
m/c complication of transpsoas lumbar instrumentation
thigh pain and psoas weakness
osteoporosis has what gene associated
COL1A1
ideal candidate for non-op for spineinfection
mssa; < 65y; no neuro sx; lumbar abscess location (vs other spine)
complication of bmp usage in PLIF
HO causing compression of neural elements
open vs tubular diskectomy for HNP
same outcome, same complication and revision surgery risk
highest risk for lumbosacral plexus during lateral approach
at l4-l5 - LS plexus lives b/w TP and vertebral body at in psoas at L4-5
baseline failure rate for non-op spine infection and risk factors for failure
IVDA, DM, > 65 y; CRP >115; WBC >12 or S. Aureus
tx of non frx with anky spondy
PSF even if non displaced
MIS vs Open TLIF Fusion rate
similar fusion rate; lower complication; shorter hospital stays
SINS criteria for instability - lower risk if
blastic; non-junctional (outside of C7-T2); no collapse even with 50% vt involvement;
what is chance fracture mechanism
distraction injury - look for tranverse pedicle fracture on axial CT
pelvic tilt in setting of lumbar lordosis
generally should be Less than 20; increased PT can indicate the amount of compensation to stand up straight
which growth factors are implicated in spinal stenosis
TNF - alpha; IL 1; MMP
rate of dysphagia in ACDF
up to 12 % of at 1 year
Wiltse approach
between the paraspinals (multifidus and longissimus) lands on the facet joints
dorsal spinal columns transmit
proprioception; vibration; deep touch
lateral spinothalamic trasmitts
pain and temp
halo for dens frx in eldery
higher risk of dysphagia
what deformity influences adult deformity patients to choose surgery
CORONAL plane deformity
MIS diskectomy associated with
increased rate of dural tear, overal complication rate is similar
sequestrectomy vs complete diskectomy
Sequestrectomy has higher recurrence rate but similar surgical time; complication, blood loss and LOS
ACDF vs posterior foraminotomy
similar function and outcome - but Posterior has higher rate of recurrence at SAME level and higher post-op neck pain
potential nerve palsy after c-spine surgery
C5 - 70% recover by 6 months but can occur up to 1 year after surgery- no treatment. Just reassure
how to reduce risk of c5 nerve palsy
prophylactic c4-5 foraminotomy; and neuromonitoring
recurrent vs superior laryngeal nerve injury
Recurrent nn innervates all muscles EXCEPT cricothyroid and will lead to hoarseness if injured; Sup. Nn is for cricothyroid and leads to voice fatigue and lost high pitch if injured
decompression of a burst fracture
best done via anterior approach; indirect decompression via posterior distraction is good but NOT AS GOOD
aorta bifurcates at which vertebral level
L4
multilevel interbody implant in osteoporotic spine
can increase the risk of subsidence
bmp 2 for spine fusion is cost effective when
considering lost wages and productivity; do NOT use in tumor fusions
tx of jumped facets in obtunded patient
OR for reduction followed by MRI to evaluate
smith pete osteotomy requires
anterior spine flexibility
sacralization of L5 vs Lumbarization of S1
up to 15% for L5 and 3-7% for S1
Bertolotti syndrome
L5 TP articulates with Sacrum - 5% and can cause LBP in young adults
what is functional spine unit
vt above and below; the disk; the paired facet joints
which facet is main compressor in lumbar radicu
SUPERIOR facet of the lower vertebrate
right vs left acdf
left side has a more predictable course of recurrenty larygneal - on right its variable under the subclavian artery often in surgical field
injury to superior laryngeal nn can lead to
loss of aspiration prevention via mucous sensory reflex
acdf landmarks
circoid MEMBRANE is C5-6; cricoid cartilage is c4-5; hyoid bone is c3 and angle of mandible is c2
TP facet relationship in lumbar spine
TP is in line with lower face
order of spinal muscles medial to lateral
interspinalis, multifidus, longissimus; iliocostalis
during lateral spine approach what do you do to hips and knees
Flex - to relax the iliopsoas
safest spot in acdf for vertebral artery
superior endplate at the uncinate process
ponticulus posticus
anatomic variant of vert artery for c1 - 15% of people
most important measurement for avoiding vert artery in C2 instrumentation
width of inferior surface of isthmus in C2
which t-spine has narrowest pedicle
T5
pedicle/TP relationship in T spine
midline TP is midline pedicle in THORACIC Spine
pedicle angles in L spine
start at 12 deg and increase to 30 deg by L5
internal carotid artery and c1 lateral mass
within 1mm of exit of c1-2 articular screw or c1 lateral mass
calf atrophy denotes which radic
chronic l5 neuropathy or S1
Reflexes
C5-biceps; C6-BR; C7- triceps;
l4 vs l5 foot sensation
L4 is MEDIAL foot; L5 is dorsal/lateral foot; S1 is pure lateral and plantar
hoffman test accuracy for myelopathy
sensitive but NOT specific
traslaminar vs transforaminal esi
TF works better and for longer but might require multiple injections
emg vs mri sensitivity vs specificity for radic
mri is more sensitive; EMG is more specific (bc motor unit changes can take up to 21 days)
T1PA iis what
angle from center of T1 to femoral head and to midpooint of sacrum < 14 is goal
coronal plumb line
line down C7 and midline sacrum - distance should be < 4cm
chin brow vertical angle
normal is -10 to +20
risk for pjk
360 fusion; fusion to sacrum;
indications for surgery in burst frx
neuro compromise; OR PLC disruption; canal compromise without symptoms or kyphosis is NOT a reason; and is NOT associated with chronic pain
smith pete osteotomy gives how much correction
10 deg;
complications and HRQOL for spinal deformity surgery
despite complicatons; most are temporary so don_t afect HRQOL; complications lower the 2 year HRQOL
bracing reduces AIS surgery by
50% with at least 12 hours a day
risk factors for persistent symptoms after myelopathy surgery
motor grade < or = 2; lost pain sensationa; multisegment disease including c5
posterior laminoplasty vs acdf
posterior has more infection risk and more neck pain
acdf placed steroid
can reduce dysphagia without causing increase in pseuoarthrosis or infection; no change in pain
epidural abscess with NO neuro sx - should you operate?
IF > 65; DM; or MRSA then YES
zero profile acdf plate does what
reduced short term and long term dysphagia withOUT change in fusion rate
cage vs graft in acdf
no difference in adjacent segment disease
risk factor for adjacent seg disease in acdf
women and smoker
delayed surgery for central cord syndrome
reduced mortality
indirect interbody decompression is how much
10-20%; putting the cage in anterior 1/3 disk space is good for restoring angle wihtout compromising the distraction
what is at risk with c1-2 screws
either lateral mass at c1 or transarticular c1-2 screws can result in injury to internal carotid
SINS scoreing
< 6 is stable, 7-12 is pending instability; 13 and up is unstable
what is neurogenic shock
c- or t- spine injuries leading to lost Autonomics; look for hypotension with BRADY cardia - tx is to give pressors (phenyl; epi; dopa/dobutamine); atropine for HR;
when to give steroids after acute spine injury
for 24 hours IF started within 3 hours
which sci has highest potential for neuro recovery
conus medullaries
alert patient with cs-pine jumped facet or perch what next
traction and reduce - do NOT sedate; MRI AFTER
which 3-column TL injury is MOST unstable
translation/rotation - most likely assoc. with complete SC injury
flexion distraction TL injury involves which columns
middle and posterior - NOT anterior
what is floating lateral mass and tx
cervical spine frx of lamina and Ipsilateral pedicle - do a 2 level ACDF -these are unstable
halo for subaxial c-spine injuries is
POOR immobilization - better for C1-2 injuries
what is predictive of myelopathy severity
transverse area of SC
age over 80 with spinal stenosis - what is outcome of Surgery
better outcomes compard to non-op
complication of stereotactic radiation
compression fracture
contraindication to c1-2 articular screw
aberrant vertebral artyery
for suspected c-spine injury first imaging of chocie
CT - NOT cspine xray
biggest risk with cervical corpectomy
midline migration of vertebral artery causing iatrogenic injury
risk factor for adjacent segment disease
lami next to a fusion
strongest reccomendation for treating osteoporotic VCF
AGAINST vertebroplasty
VCF on MRI has what feature
Low T1 and high signal on STIR
what is measurement is correlated to high grade spondylisthesis
Pelvic incidence - NOT slip angle or percentage; not sacral slope
where is superior hypogastric plexus in relation to spine
at level of L5-S1
sympathetic chain location in anterior spine
medial to psoas border behind the great vessels
lumbar disc replacement vs fusion
increased pt satisfaction at 2 years for LDR
treatment for far lateral disc herniations
extraforaminal diskectomy
which nerves are at risk during transpsoas l4-5 approach
ilioinguinal and iliohypogastric - sit b/w int/ext obliques above iliac crest
what Is r/f for highest complication in spinal deformity surgery
age >60
moA denosumab
blocks osteoCLASTS - dmAB binds to RANKL (from osteoblasts) blocking its activiation of osteoclasts
cervical stenosis involving 3 or more levels
check to see if alignment allows for posterior decompression-fusion
which frx have higher risk of vert artery injury
highest with basical skull frx; OC dissocitaion or frx in HYPER ostotic spine; also if they invovle transverse foramen
moA of gabapentin
binds to pre-synapse Ca channels and prevents neurotransmitter release
DISH spine and SI joints
they are SPARED - it_s a non-inflammatory condition - associated with DM - track A1c
spinal stenosis neuro exam
sx only when walking; neuro sx should be absent while sitting
athetoid cerebral palsy seen with
kernicterus and jaudince - look for early cervical spine disease, disc degen
displaced odontoid fractures - first step
always reduce - then OR
unstable peds os odontoideum tx
c1-2 fusion
tspine disc herniation ct appearance
often have calcifications
children under 2 with spine frx what is NAT rate
40% are due to non-accidental trauma
percentage of multiple myeloma with vcf
up to70% get vcf
intra-op monitoring - which is most SPECIFIC for sc injury
Transcranial MEP is most specific; SSEP are NOT as Sn/Sp
intra-op EMG used for
nerve root injury - ie during screw placement
risk of adjacent segment disease with wrong needle placement
increased risk for adjacent segment disease
Rha pre-op spine imaging -what is needed
flex/extension c-spine xray
osteotomy of choice during long curves
smith pete - ie during schuermans
intra-op tx to prevent PJK in lumbar fusions
in long lumbar fusions; augmenting the level ABOVE the fusion can help acute PJK from VCF - by using vertebroplasty
when can you return to high intensity exercise after diskectomy
4 weeks is safe
which mri findings in myelopathy mean poor prognosis
low t1 signal; high t2 signal
timing of bone scan for VCF
wait at least 7-10 days; in acute phase it can lead to false negative
what changes in pelvis to accomdate positive sagittal balance
pelvic retroversion
if patient still septic after epidural abscess drainage then what next
MRI entire spine for skip lesions; even if psoas abscess present
first step in bilatearl disc herniation if obtunded
get MRI to make sure disk isnt herniated - this would require an anterior approach
PADI limit for surgery in RhA
if less than 13
composition of obturator nerve
L1-3
sciatic vs femoral nn contributions
Sciatic - L4,L5,S1; Femoral L3-4 - therfore L4 goes to BOTH
after bisphos tx is maxed out what next for VCF prevention
add teraparatide
in order to correct saggital balance in previous fusion you need
fusion to pelvis with PSO - smith pete requires OPEN disc space
where does recurrent laryngeal nerve run
between tracheoesopahgeal interval
