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123
CristianGragnaniello· GabrielTender·
KevinPhan· RalphMobbs·
RemiNaderEditors
MCQs in Spine
Surgery
MCQs in Spine Surgery
Cristian Gragnaniello
•
Gabriel Tender
•
Kevin Phan
•
Ralph Mobbs
•
Remi Nader
Editors
MCQs in Spine Surgery
123
Editors
Cristian Gragnaniello
The University of Texas Health Science
Center at San Antonio
San Antonio, TX, USA
Gabriel Tender
Louisiana State University
New Orleans, LA, USA
Kevin Phan
School of Clinical Medicine
University of New South Wales (Sydney)
Randwick, NSW, Australia
Ralph Mobbs
Prince of Wales Hospital
Randwick, NSW, Australia
Remi Nader
University of Texas Medical Branch
Galveston, TX, USA
ISBN 978-3-031-69331-1 ISBN 978-3-031-69332-8 (eBook)
https://doi.org/10.1007/978-3-031-69332-8
© The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature
Switzerland AG 2024
This work is subject to copyright. All rights are solely and exclusively licensed by the Publisher, whether the whole or
part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation,
broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and
retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter
developed.
The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not
imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and
regulations and therefore free for general use.
The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed
to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty,
expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been
made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional
affiliations.
This Springer imprint is published by the registered company Springer Nature Switzerland AG
The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland
If disposing of this product, please recycle the paper.
Contents
1 Anatomy, Embryology, Examination and Imaging of the Spine ........... 1
Zayed Almadidy, Darius Ansari, and Saavan Patel
2 Surgical Anatomy and Techniques to the Spine
....................... 33
Asham Khan, Moleca M. Ghannam, Ryan M. Hess, Slah Khan,
Alexander O. Aguirre, Cathleen C. Kuo, Ali Y. Elkady, Ahmed H. Omar,
Mohammad Elbaroody, and Mohamed A. R. Soliman
3 Instrumentation
............................................... 55
Asham Khan, Moleca M. Ghannam, Ryan M. Hess, Slah Khan,
Alexander O. Aguirre, Cathleen C. Kuo, Ali Y. Elkady, Ahmed H. Omar,
Mohammad Elbaroody, and Mohamed A. R. Soliman
4 Bone Biology and Bone Substitutes
................................ 69
Asham Khan, Moleca M. Ghannam, Ryan M. Hess, Slah Khan,
Alexander O. Aguirre, Cathleen C. Kuo, Ali Y. Elkady, Ahmed H. Omar,
Mohammad Elbaroody, and Mohamed A. R. Soliman
5 Intraoperative Neuromonitoring
................................... 83
Asham Khan, Moleca M. Ghannam, Ryan M. Hess, Slah Khan,
Alexander O. Aguirre, Cathleen C. Kuo, Ali Y. Elkady, Ahmed H. Omar,
Mohammad Elbaroody, and Mohamed A. R. Soliman
6 Minimally Invasive Spine Surgery
................................. 93
Asham Khan, Moleca M. Ghannam, Ryan M. Hess, Slah Khan,
Alexander O. Aguirre, Cathleen C. Kuo, Ali Y. Elkady, Ahmed H. Omar,
Mohammad Elbaroody, and Mohamed A. R. Soliman
7 Degenerative Conditions of the Spine
............................... 103
Teresa Somma, Domenico Solari, Vincenzo Meglio, Lorenzo Ugga,
Oreste de Divitiis, and Paolo Cappabianca
8 Pediatric Spine
................................................ 149
Christopher Sy, Alexander Villahermosa, Jonathan Fisher, Molly Farrell,
Ryan McDermott, and Daniel Smerin
9 Tumors, Infections, Inflammatory and Vascular Lesions of the Spine
...... 167
Ravi Nunna, Michael Torres, Wesley Chen, and Sasidhar Karuparti
10 Complications of Surgery of the Spine
.............................. 199
Antonio Bocchetti, Ciro Mastantuoni, Valentina Cioffi,
and Raffaele de Falco
11 Biomechanics of the Spine
....................................... 235
Luke Antonio Silveira, Anvitha Sathya, and Ryan Jewell
12 Trauma of the Spine. Chronic Pain
................................ 263
Morteza Sadeh
v
1
Anatomy, Embryology, Examination
and Imaging of the Spine
Zayed Almadidy, Darius Ansari, and Saavan Patel
1. A 73-year-old woman is being evaluated in the emer-
gency department due to acute-onset back pain. Past
medical history is significant for osteoporosis diagnosed
via dual-energy x-ray absorptiometry (DEXA) 10 years
ago. Imaging reveals compression fractures of T10 and
T11. Given these findings, which portion of the vertebrae
is most likely to be fractured in this patient?
a. Intervertebral disc
b. Transverse process
c. Superior articular process
d. Vertebral body
e. Lateral mass
Preferred Response: (d) Vertebral body. Vertebral com-
pression fractures, which most commonly occur in the set-
ting of osteoporosis, are typically anterior column injuries
resulting from compression with flexion. The transverse and
superior articular processes can be injured durin g trauma, but
are more likely to occur due to oblique, transverse, or
comminuted fractures. The intervertebral discs are not
associated with compression fractures. The lateral mass is a
structure present in the cervical spine [1].
2. An individual is being evaluated in the emergency
department after major trauma. Upon evaluation , the
patient is intubated, holding their arms in pronation and
extension, and extending their lower extremities. Damage
to which of the following structures is most likely
responsible for this type of positioning in this patient?
a. Rubrospinal tract
b. Dorsal column-medial lemniscus pathway
c. Spinothalamic tract
d. Vestibulospinal tract
e. Pontine reticulospinal tract
Preferred Response: (a) Rubrospinal tract. The patient
described is in decerebrate posturing. Lesions that interrupt
fibers of the red nucleus lead to inhibition of the rubrospinal
tract and constant excitation of the vestibulospinal and
pontine reticulospinal tracts. The unopposed, continuous
excitation results in extensor posturing when stimulation is
applied. The spinothalamic tract is also typically injured in
such lesions but continues to give off reticular fibers below
the lesion to the reticular formation and other pontine nuclei
and is not responsible for the maintenance of flexion [2].
3. In the evaluation of a patient complaining of radicular
pain, the attending radiologist read of an MRI notes disc
herniation at L4-L5. An extreme lateral disc herniation
involving the foraminal zone at the level of L4- L5 is
most likely to affect which of the following nerve roots?
a. L3
b. L4
c. L5
d. S1
e. None
Preferred Response: (b) L4. While central and paramedian
disc herniations typically involve the traversing nerve root
and therefore usually 1 level below (in this case, the L5
nerve root), far lateral disc herniations involving the
foraminal zone involve the nerve root exiting at that level (in
this case, the L4 nerve root). The L3 nerve root is unlikely to
be affected by such a lesion as it has already exited the spinal
canal. Similarly, an L4-L5 far late ral disc herniation is
unlikely to produce symptomatic compression of the S1
nerve root.
Z. Almadidy (&) D. Ansari S. Patel
Department of Neurosurgery, University of Illinois at Chicago,
Chicago, USA
e-mail: zalmad3@uic.edu
D. Ansari
e-mail: dansari2@uic.edu
S. Patel
e-mail: spate327@uic.edu
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2024
C. Gragnaniello et al. (eds.), MCQs in Spine Surgery,
https://doi.org/10.1007/978-3-031-69332-8_1
1
4. Which of the following is the most appropr iate nonin-
vasive imaging technique to order to differentiate spinal
abscess from primary tumor?
a. CT without contrast
b. CT with and without contrast
c. MRI without contrast
d. MRI with and without contrast
Preferred Response: (d) MRI with and without contrast.
Although distinguishing infectious from neoplastic pro-
cesses can be challenging based on imaging data alone, MRI
is the investigation of choice for differentiating several spinal
pathologies. On MRI scan, abscesses appear iso-intense or
hypo-intense on T1-weighted images and hyperintense on
T2-weighted images. Contrast studies show a peripheral rim
of enhancement. Conversely, contrast MRI studies of
ependymomas and meningiomas typically enhance homo-
geneously. MRI scan without contrast would provide less
discriminatory capability as tumors such as ependymomas
may appear iso-intense on T1 and hyperintense on
T2-weighted images, similar to abscesses [3].
5. A 59-year-old man presents to the office with complaints
of low back pain and weakness in his left leg. MRI
demonstrates compression of the exiting nerve root
between L4 and L5 vertebrae. Which of the following
structures is most likely responsible for producing this
lesion?
a. Posterior longitudinal ligament
b. Annulus fibrosus
c. Interspinous ligament
d. Ligamentum flavum
e. Nucleus pulposus
Preferred Response: (e) Nucleus pulposus. Nerve com-
pression at the intervertebral foramen is most commonly
caused by a disc herniation. Disc herniation is caused by
herniation of the nucleus pulposus through the annulus
fibrosus, which can affect the spinal canal or the interver-
tebral foramen. The posterior longitudinal ligament is loca-
ted posterior to the disc space, but symptomatic disc
herniations generally are the result of posterolateral hernia-
tion of the nucleus pulposus. The interspinous ligament is
located in the posterior column and would not be responsible
for the described MRI findings. The ligamentum flavum may
become hypertrophied, causing symptoms of canal stenosis,
but unilateral compression at the intervertebral foramen is
more likely to be caused by herniated nucleus pulposus [1 ].
6. A 79-year-old man experiences cramping pain in his low
back and bilateral legs while walking. He states that this
has gradually progressed over several months. His pain is
worsened while walking downhill, and relieved by rest-
ing or bending forwards while walking. On examination,
peripheral pulses are intact. MRI of the lumbar spine
reveals non-displaced intervertebral discs and increased
thickening of the posterior spinal canal with compression
of the posterior thecal sac. Which of the following
structures is most likely responsible for this patient’s
symptoms?
a. Posterior longitudinal ligament
b. Annulus fibrosus
c. Interspinous ligament
d. Ligamentum flavum
e. Nucleus pulposus
Preferred Response: (d) Ligamentum flavum. Hypertrophy
of the ligamentum flavum can cause symptoms of lumbar
spinal stenosis, as observed in this elderly gentl eman with
cramping pain while walking (“neurogenic claudication”).
7. A patient with a history of advanced renal cell carcinoma
undergoes elective commissural myelotomy. As part of
the procedure, an incision is made through the fibers of
the anterior white commissure of the spinal cord. Deficits
in which of the following would be expected as a result
of this injury? There may be mul tiple correct answers.
a. Proprioception
b. Pain sensation
c. Vibratory sensation
d. Temperature sensation
e. Fine touch discrimination
f. a + b
g. b + c
h. b + d
i. b + d + e
Preferred Response: (h) Pain sensation and Temperature
sensation. A lesion affecting the anterior white commissure
of the spinal cord would affect the second-order neurons of
the spinothalamic tract, resulting in deficits of pain, tem-
perature, pressure, and crude (rather than fine) touch. Fol-
lowing decussation of the second-order neurons in the
spinothalamic tract, these fibers ascend and synapse in the
ventral posterolateral nucleus of the thalamus. Additionally,
up to 15% of corticospinal tract fibers cross at the anterior
white commissure. Proprioception, fine touch, and vibration
are primarily governed by the dorsal column medial lem-
niscus tract, which would be spared in an isolated lesion to
the anterior white commissure [4].
8. Which of the following is the correct sequence of
structures of the spinothalamic tract from distal to
proximal?
2 Z. Almadidy et al.
a. Sensory nerve ending > ipsilateral gray matter of
spinal cord > anterior white commissure > VPL
nucleus of the thalamus > 1˚ somatosensory cortex
b. Sensory nerve ending > ventral horn of spinal
cord > anterior white commissure > VPL nucleus of
the thalamus > 1˚ somatosensory cortex
c. Sensory nerve ending > nucleus gracilis/cuneatus
> medial lemniscus > VPL nucleus of the thala-
mus > 1˚ somatosensory cortex
d. Sensory nerve ending > ipsilateral gray matter of
spinal cord > anterior white commissure > VPM
nucleus of the thalamus > 1˚ somatosensory cortex
Preferred Response: (a) Sensory nerve ending > ipsilateral
gray matter of spinal cord > anterior white commis-
sure > VPL nucleus of the thalamus > 1˚ somatosensory
cortex. The nucleus gracilis and medial lemniscus are
involved in the dorsal-column medial lemniscus tract. The
ventral horn of the spinal cord contains cell bodies involved in
the descending corticospinal tract. The ventral posteromedial
nucleus of the thalamus is involved in facial sensation [5].
9. A child with history of neurofibromatosis type 2 is
undergoing an anterolateral cordotomy for intractable
pain secondary to a sciatic nerve tumor. Preoperatively,
the patient undergoes high-resolution MRI to locate the
dentate ligament. The dentate ligament serves as an
important intraoperative landmark between two spinal
cord structures, which ones?
a. Lateral corticospinal tract and dorsal columns
b. Anterior corticospinal tract and lateral spinothalamic
tract
c. Lateral spinothalamic tract and anterior spinocere-
bellar tract
d. Lateral corticospinal tract and lateral spinothalamic
tract
e. Anterior spinocerebellar tract and anterior corti-
cospinal tract
Preferred Response: (d) Lateral corticospinal tract and
lateral spinothalamic tract. The dentate ligament is located
immediately ventral to the lateral corticospinal tract and
dorsal to the spinothalamic tract. Identification of this liga-
ment preoperatively (if possible) and intraoperatively during
an anterolateral chordotomy is critical for definition of the
desired lesion [6].
10. A patient with longstanding history of alcoholism pre-
sents to the office with progressive fatigue, gait ataxia,
and bilateral lower extremity paresthesias. Physical
examination discloses diminished sensation to light
touch and vibration over the bilateral lower extremities,
with positive Romberg sign. Complete blood count
reveals macrocytic anemia. Which of the following
findings confers the highest sensitivity for the patient’s
suspected condition?
a. Decreased serum cobalamin levels
b. Peripheral blood smear with hyper segmented
neutrophils
c. Increased serum methylmalonic acid and
homocysteine
d. Decreased cobalamin on Schilling test
e. Increased serum anti-Intrinsic factor levels
Preferred Response: (c) Increased serum methylmalonic
acid and homocysteine. This patient is presenting with
symptoms of subacute combined degeneration, a demyeli-
nating disorder as a result of low levels of cobalamin (vi-
tamin B12). High serum concentrati ons of methylmalonic
acid and homocysteine (metabolites of cobalamin) are the
most sensitive indicators of intracellular cobalamin defi-
ciency. Their levels are high in more than 90% of patients
with cobalamin deficiency and are elevated before serum
levels of cobalamin fall below normal limits [7].
11. A 63-year-old woman is diagnosed with herpes zoster
virus infection after presenting to the office with painful
rash in a T6 distribution on the left side. In which of the
following structures did the virus proliferate to cause
the patient’s symptoms?
a. Lateral horn of the T6 spinal cord segment
b. Posterior cutaneous branch of the dorsal ramus
of T6
c. Ventral horn of the T6 spinal cord segment
d. Dorsal root ganglion of the T6 spinal nerve
e. Greater chain ganglion of the sympathetic plexus
Preferred Response: (d) Dorsal root ganglion of the T6
spinal nerve. Herpes zoster virus infection (“shingles”)
remains latent in the dorsal root ganglia of sensory nerves.
Upon reactivation, symptoms include painful skin rash in a
dermatomal distribution of the affected nerve. Affected
patients may develop postherpetic neuralgia (PHN), a con-
dition characterized by residual pain following the disap-
pearance of the primary rash. PHN refractory to medical
management may be the target of neurosurgical intervention
with procedures such as spinal cord stimulation, dorsal root
ganglion stimulation, dorsal root entry zone lesioning, sub-
cutaneous peripheral nerve stimulation, among others [8].
12. Which of the following ligaments provides the majority
of the strength to the atlantoaxial joint, considered the
strongest ligament of the craniocervical junction?
a. Alar ligament
b. Transverse atlantal ligament
1 Anatomy, Embryology, Examination and Imaging of the Spine 3
c. Cruciate ligament, descending band
d. Apical odontoid ligament
Preferred Response: (b) Transverse atlantal ligament
(TAL). The TAL attaches at the medial tubercles of the atlas
and secures the dens against the anterior arch of the atlas.
Several cadaveric studies have demonstrated that the TAL
can sustain the most force of any ligament prior to rupture.
The atlanto-alar portion of the alar ligament and the cruciate
ligament also secure the axis to the atlas, but do not con-
tribute as much strength as the TAL. The apical odontoid
ligament is a weak structure that originates at the tip of the
dens and attaches to the foramen magnum [9].
13. Which of the following combinations of ligaments are
considered most crucial for maintaining atlantooccipital
stability?
a. Tectorial membrane and alar ligament
b. Tectorial membrane and cruciate ligament
c. Cruciate ligament and alar ligament
d. Apical dentate ligament and tectorial membrane
e. Cruciate ligament and apical dentate ligament
Preferred Response: (a) Tectorial membrane and alar
ligament. The tectorial membrane, alar ligament, cruciate
ligament, and apical dentate ligament all secure the
atlantoaxial region to the occiput. However, violation of the
tectorial membrane and alar ligament are more likely to
cause atlantoocc ipital instability than the cruciate ligament
and apical dentate ligament [10].
14. A 32-year-old female athlete presents to the office with
a 1-month history of pain, weakness, and numbness in
her right arm. She undergoes MRI which demonstrates
posterolateral herniation of a cervical vertebral disc. She
undergoes anterior cervical discectomy and fusion with
intraoperative findings of severely damaged nucleus
pulposus and annulus fibrosus. What are the embry-
ologic origins of the nucleus pulposus and annulus
fibrosus, respectively?
a. Neural crest cells and endoderm
b. Notochord and ectoderm
c. Mesenchymal cells from sclerotome and notochord
d. Notochord and neural crest cells
e. Notochord and mesenchymal cells from sclerotome
Preferred Response: (e) Notochord and sclerotome. The
nucleus pulposus is formed by the remnant of the notochord
and the annulus fibrosus is derived from surrounding scle-
rotome mesenchyme. The ectoderm and endoderm are not
involved in the formation of the intervertebral disc struc-
tures. The neural crest cells give rise to several diverse
lineages of cells including smooth muscle, peripheral enteric
neurons, glial cells and melanocyt es, but not the nucleus
pulposus or annulus fibrosus [11].
15. A 6-month-old male is brought to the office for a rou-
tine well-child visit. The child appears and feels normal
except for an isolated tuft of hair growing over the
midline of the lumbar region with a shallow dimple.
There is no evidence of skin thinning or open defects.
This finding is most likely attributable to which of the
following embryological phenomena?
a. Normal neurological development
b. Failure of the caudal neuropo re to close without
herniation
c. Failure of the caudal neuropore to close with
meningeal herniation
d. Herniation of cauda equina through a bony defect
e. Failure of the rostral neuropore to close without
herniation
f. Failure of the rostral neuropore to close with
meningeal herniation
Preferred Response: (b) Failure of the caudal neuropore to
close without herniation. The condition described is most
likely spina bifida occulta, which typically manifests as a
dimple with a tuft of hair over the bony defect. Failure of the
caudal neuropore to close with meningeal herniation
describes a meningocele. Herniation of the cauda equina
would be seen in a myelomeningocele (both neural tissue
and meninges). Failure of the rostral neuropore to close
results in anencephaly.
16. A newborn is diagnosed with myelomeningocele.
Which of the following weeks of gestational develop-
ment did this occur?
a. Week 2
b. Week 3
c. Week 4
d. Week 6
e. Week 8
Preferred Response: (c) Week 4. Neural tube defects such
as myelomeningocele are the result of failure of the caudal
neuropore to close in week 4 during the process of
neurulation.
17. What carotid-vertebrobasilar anastomoses may be pre-
sent at the craniovertebral junction?
a. Proatlanto intersegmental artery and transverse cer-
vical artery
b. Sternocleidomastoid branch of occipital artery and
persistent hypoglossal artery
4 Z. Almadidy et al.
c. Transverse cervical artery and persistent hypoglos-
sal artery
d. Proatlanto intersegmental arter y and persistent
hypoglossal artery
Preferred Response: (d) Proatlanto intersegmental artery
and persistent hypoglossal artery. These anastomoses may
be encountered at the approach to the craniovertebral junc-
tion. Thin-cut CT angiography may be useful preoperatively
to evaluate the patency of the vertebral arter ies and to
localize any aberrant vascular anatomy. The sternocleido-
mastoid branch of the occipital artery is located anterior to
the spine and is not in the craniovertebral junction area. The
transverse cervical artery is the middle branch of the thy-
rocervical trunk, from the subclavian artery [12].
18. A 41-year-old male is evaluated in the emergency
department following a motor vehicle collision in which
he was an unrestrained driver. Among other injuries,
non-contrast CT scan of the cervical spine reveals a
fracture of the transverse process of the C4 vertebrae on
the left with surround ing hyperdensity. Given this
finding, which artery is most likely to be damaged?
a. Inferior thyroid artery
b. Anterior spinal artery
c. Posterior spinal arteries
d. Vertebral artery
Preferred Response (d) Vertebral artery. An injury to the
transverse process is most likely to damage the vertebral
artery, which courses through the transverse foramina of C6
to C1. The inferior thyroid artery and anterior spinal artery
are located anteriorly and are not like ly to be damaged in
direct association with a transverse process fracture. The
posterior spinal arteries are adherent to the posterior aspect
of the spinal cord and are not directly associated with the
transverse processes.
19. Which of the following is not an element of the National
Emergency X-Radiography Utilization Study (NEXUS)
criteria that must be present to determine that a trauma
patient does not require cervical spine imaging?
a. Alert and stable
b. Absence of focal neurological deficit
c. Presence of witness at time of injury
d. Lack of intoxication
e. Lack of midline spinal tenderness
Preferred Response: (c) Presence of witness at time of
injury. The NEXUS criteria have a sensitivity of 99.6% for
ruling out cervical spine injury when all elements are present.
These include alert and stable, lack of the following: focal
neurological deficit, altered consciousness, neurological
deficit, midline spinal tenderness, and distracting injury [13].
20. A patient is being evaluated in the emergency depart-
ment following a motor vehicle collision. Past medical
history significant for atrial fibrillation for which the
patient takes Warfarin. Imaging reveals bleeding from
Batson’s venous plexus, with adjacent hematoma. In
which space has the blood most likely accumulated to
produce this finding?
a. Superficial subcutaneous tissue
b. Epidural space
c. Subdural space
d. Subarachnoid space
e. Central canal
f. Lumbar cistern
Preferred Response: (b) Epidural space. The internal ver-
tebral plexus (Batson’s venous plexus) is located within the
epidural space and surrounds the dura mater. Bleeding from
the plexus would therefore cause accumulation of blood in
the epidural space. Spinal epidural hematomas are rare, but
the primary risk factor is anticoagulation. The most common
cause of subarachnoid blood accumulation are subarachnoid
hemorrhages. Subdural hematoma is more commonly
encountered as an intracranial venous bleed as a result of
injury to the cerebral veins. The lumbar cistern is a contin-
uation of the subarachnoid space between the caudal conus
medullaris and caudal end of the subarachnoid space. The
central canal is located within the spinal cord and does not
contain the Batson’s venous plexus.
21. Which of the following structures is primarily respon-
sible for maintaining the midline position of the spinal
cord?
a. Denticulate ligaments
b. Posterior longitudinal ligament
c. Ligamentum flavum
d. Nuchal ligament
e. Transverse ligament of the atlas
Preferred Response: (a) Denticulate ligaments. The den-
ticulate ligaments are extensions of the pia mater that attach
to the dura between the dorsal and ventral roots of the spinal
nerves. The function of these ligaments is to maintain the
midline position of the spinal cord within the canal. The
posterior longitudinal ligament courses along the posterior
aspect of the vertebral bodies within the canal and functions
1 Anatomy, Embryology, Examination and Imaging of the Spine 5