1.Which structure passes through the superior orbital fissure?
A. Optic nerve.
B. Maxillary division of the trigeminal nerve (CN V-2)
C. Abducens nerve (CN VI)
D. Ophthalmic artery
E. Facial nerve (CN VII)
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Answer: C. Abducens nerve. CN III (oculomotor), CN IV (trochlear), and CN VI (abducens) pass through the superior orbital fissure, as well as the ophthalmic vein and several branches of the ophthalmic branch of the trigeminal nerve (V-1). CN II (optic) and the ophthalmic artery pass through the optic foramen. The maxillary branch of the trigeminal nerve (V-2) passes through foramen rotundum and the mandibular branch (V-3) through foramen ovale. All of these passages are in the sphenoid. The facial nerve (VII) passes through the stylomastoid foramen of the temporal bone.
2. Which 2 cranial bones are on either side of the jugular foramen?
A. Occiput & sphenoid
B. Temporal & sphenoid
C. Parietal & temporal
D. Temporal & occiput
E. Parietal & occiput
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Answer: D. The jugular foramen is an aperture in the base of the skull, bordered on the anterior by the petrous portion of the temporal bones, and posteriorly by the occiput.
3. What is/are the axis/axes of rotation in a superior vertical strain?
A. One A-P axis
B. One vertical axis
C. Two parallel vertical axes
D. Two parallel transverse axes
E. Three axes: two parallel vertical axes and one A-P axis
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Answer: D. The sphenoid and the occiput rotate in the same direction around 2 parallel transverse axes – one through the body of the sphenoid and one superior to the foramen magnum of the occiput. The strain is named based on the position of base of the sphenoid. In a superior vertical strain, the base of the sphenoid will be high, and the greater wings will tilt anterior-inferiorly.
4. What is/are the axis/axes of rotation in a left torsion?
A. One A-P axis
B. One vertical axis
C. Two parallel vertical axes
D. Two parallel transverse axes
E. Three axes: two parallel vertical axes and one A-P axis
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Answer: A. The sphenoid and occiput rotate in opposite directions around an A-P axis. The torsion is named for the side on which the greater wing of the sphenoid is high, so in a left torsion the left greater wing will be high and the right greater wing will be low.
5. The dura attaches to the vertebral column at:
A: Foramen magnum, C2, L5
B. C2, C3, conus medullaris
C. Foramen magnum, C1, S1
D. Foramen magnum, C2, S2
E. C2, C3, conus medullaris
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Answer: D. The firm attachments of the dura in the vertebral column are at foramen magnum, C2-C3, and S2. This is known as the core link.
6. What is/are the axis/axes of rotation in a lateral strain?
A. One A-P axis
B. One vertical axis
C. Two parallel vertical axes
D. Two parallel transverse axes
E. Three axes: two parallel vertical axes and one A-P axis
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What is/are the axis/axes of rotation in a lateral strain?
Answer: D. The sphenoid and the occiput rotate in the same direction around 2 parallel vertical axes.
7. Which of the following accurately describes the motion of the cranial bones during flexion of the PRM?
A. The SBS rises, greater wings descend and widen, foramen magnum moves anterior & superior, and the tips of the mastoid processes move medially.
B. The SBS rises, foramen magnum moves inferiorly, zygoma bones move medially, and parietal bones exteriorly rotate
C. The parietals exteriorly rotate, the SBS descends, the dental arch widens, and greater wings of the sphenoid rise.
D. The SBS descends, the foramen magnum moves inferior & posterior, the ethmoid spine ascends, and the dental arch widens.
E. The temporal bones exteriorly rotate, the A-P dimension of the face increases, the ethmoid spine ascends, and the tips of the mastoid processes widen.
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Answer: A. In flexion, the midline bones rotate as the SBS rises. The ethmoid spine descends, the greater wings descend and widen, bringing the laternal angles of the frontal bones with them. The metopic suture of the frontal bone recedes posteriorly, as the face shortens along an A-P axis. Temporals and parietals both exernally rotate, and the tips of the mastoid process moves posteromedially as the temporal rotates about a diagonal axis that diverges anteriorly.
8. What is the name for the intersection of the sagittal and coronal sutures?
A. Opisthion
B. Glabella
C. Nasion
D. Bregma
E. Pterion
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Answer: D. Bregma is at the top of the head where the sagittal & coronal sutures intersect. Opisthion is the midpoint on the posterior margin of the foramen magnum, on the occiputal bone. Glabella is a depression point on the metopic suture of the between the 2 superciliary arches of the frontal bone, and above nasion. Nasion is the intersection of the frontal bone with the 2 nasal bones, just above the bridge of the nose. Pterion is the region on the side of the skull where the frontal, parietal, temporal, and sphenoid come together.
9. Which structure is accurately placed?
A. The styloid process is part of the Parietal bone.
B. The metopic suture is part of the Palatine bone.
C. The petrous ridge is part of the Temporal bone.
D. The jugular foramen part of the in Sphenoid bone.
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Answer. C. The petrous ridge is the ridge on the superior aspect of the petrous portion of the temporal bone, with the cochlear and vestibular structures located within the petrous portion of the temporal bone. The styloid process is off the inferior side of the temporal bone (attachments include the stylohyoid muscle and ligament, stylomandibular ligament, styloglossus muscle, stylopharyngeus muscle). The metopic suture is the suture (usually but not always fused in adults) of the frontal bone(s). Foramen ovale, foramen rotundum, and foramen spinosum all pass through the sphenoid; the jugular foramen passes between the temporal-occiputal suture.
10. Looking at the vault from the vertex, you notice a bulge on the right and the right ear appears to be more posterior. What strain pattern would you expect?
A. Right side-bending rotation
B. Left lateral strain
C. Left side-bending rotation
D. Right lateral strain
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Answer. A. Right side-bending rotation.
