Self-Assessment Examination 201
2015
AAOS
Yowr Sorefor Lifelong Orthopaedic learig
,1 - Figures 1 and 2 are CT scans obtained from a 68-year-old man who has had progressive neck pain and stiffness,
worsening gait imbalance, upper extremity weakness, early muscle fatigue, difficulty with fine motor control, and
difficulty with activities of daily living over the past few years. On physical examination, he has a wide based stiff legged
gait, generalized upper extremity weakness, dense sensory loss in the upper and lower extremities, and markedly brisk
reflexes. What is the most appropriate treatment for this patient?
Figure 1 Figure 2
A. Observation
B. Cervical epidural injections
C. Multilevel anterior cervical decompression and fusion
D. Posterior cervical laminoplasties from C3-6
Correct answer: D
This patient has progressive myelopathy secondary to ossification of the posterior longitudinal ligament. Diagnostic
imaging reveals multilevel cervical cord compression from C4-6. The patient has maintained reasonable cervical lordosis.
A posterior procedure such as multilevel laminoplasty decompresses the spine, is motion preserving, and has a low
complication rate. Observation and cervical epidural injections are not viable options in patients with progressive
myelopathy. Anterior cervical decompression, including corpectomy, is an option; however, anterior procedures have an
increased risk of complications such as dural tear or cerebrospinal fluid leak. The axial CT image shows a "double layer"
sign, which is consistent with dural ossification and increases the risk of dural injury with anterior decompression.
2 - When compared with posterior decompression and fusion, the addition of an interbody fusion for the treatment of
degenerative spondylolisthesis and stenosis has been shown to
A. result in increased patient functional outcome scores.
B. reduce the incidence of symptomatic pseudarthrosis.
, C. increase the length of hospital stay.
D. increase hospital costs.
Correct answer: D
The use of an interbody graft has been shown to increase hospital costs. Gottschalk and associates found no
change in Oswestry Disability Index (ODI) or 36-Item Short-Form Health Survey (SF-36) scores when
comparing patients fused using either posterior fusion or transforaminal interbody fusion. They also found no
change in fusion rates at 3 years after surgery. Carreon and associates showed some that using a posterior place
interbody transforaminal lumbar interbody fusion (TLIF) or posterior lumbar interbody fusion (PLIF) did result
in improved ODI and SF-6D scores but did not result in any change in EuroQol five dimensions questionnaire
(EQ-5D) scores. Using the EQ-5D data, they estimated that the use of an interbody graft becomes cost
prohibitive if the charges exceed $1,570 above the cost of a posterior fusion. The use of an interbody cage has
not been shown to increase hospital stay.
3 - Figures 1 and 2 are MRI images obtained from a 22-year-old man who fell from a 2-story building. On examination, he
has diminished rectal tone and urinary retention. If surgical stabilization is elected, what is the most biomechanically
stable option?
Figure 1 Figure 2
A. Sacral plating
B. Iliosacral screws
C. Iliosacral screws and lumbopelvic fixation
D. External fixation
, Correct answer: C
The dpatient dhas da dU-shaped dsacral dfracture dor dspondylopelvic ddissociation. dTreatment doptions dfor dthese
dfractures drange dfrom dpercutaneous dplacement dof diliosacral dscrews dto dlumbopelvic dfixation d(lumbar dpedicle
dscrews dand diliac dscrews).
Lumbopelvic dfixation dcan dbe dsupplemented dby diliosacral dscrews, dwhich dhas dbeen dtermed dtriangular
dosteosynthesis. dBiomechanical dstudies dhave dshown dthat diliosacral dscrews dwith dlumbopelvic dfixation—or
dtriangular dosteosynthesis—is dthe dmost dstable dconstruct dwhen dcompared dwith diliosacral dscrews dalone. dThe
dadvantage dof dlumbopelvic dfixation dis dthat dconcurrent dsacral dlaminectomy dcan dbe dperformed, dwhich dis
drecommend din dthis dpatient dbecause dof dhis dneurologic dsymptoms. dExternal dfixation dor dsacral dplating dplay
dminimal droles din dU-shaped dsacral dfractures.
4 - dClinical dSituation
Figure d1 dshows da dCT dfrom dthe dcervical dspine dof dan d85-year-old dwoman dwho dfell dfrom da dstanding
dheight d1 dweek dearlier. dShe dis dindependent dand dambulatory dand dresides din dan dassisted dliving dfacility.
dShe dreports dpersistent dneck dpain dbut ddenies darm dpain dor dweakness. dShe dis dneurologically dintact.
Fractures din dthis dregion dof dC2 dhave da dhigh drisk dof
Figure 1
A. spinal dcord dinjury.
B. union.
C. nonunion.
D. stroke.