In a superior vertical shear, the sphenoid's greater wing moves which way relative to the occiput, and the occiput moves which way?

In a superior vertical shear, the sphenoid's greater wing moves which way relative to the occiput, and the occiput moves which way?

• A. Greater wing of sphenoid → Inferior; Occiput → Superior
• B. Greater wing of sphenoid → Superior; Occiput → Inferior
• C. Greater wing of sphenoid → Inferior; Occiput → Inferior
• D. Greater wing of sphenoid → Superior; Occiput → Superior

Answer: (A)

In vertical strains, the sphenoid and occiput move in opposite directions along the vertical axis. The name indicates which bone ends up higher. For a superior vertical shear, the occiput moves upward (superiorly) while the sphenoid moves downward (inferiorly) relative to the other bone. So the greater wing of the sphenoid shifts inferiorly relative to the occiput, and the occiput shifts superiorly. This opposite-direction displacement along the vertical axis is the hallmark of a vertical strain.

In vertical strains, the sphenoid and occiput move in opposite directions along the vertical axis. The name indicates which bone ends up higher. For a superior vertical shear, the occiput moves upward (superiorly) while the sphenoid moves downward (inferiorly) relative to the other bone. So the greater wing of the sphenoid shifts inferiorly relative to the occiput, and the occiput shifts superiorly. This opposite-direction displacement along the vertical axis is the hallmark of a vertical strain.