The second occurrence of number 3 corresponds to which trauma?

• A. Left torsion
• B. Right torsion
• C. Inferior vertical strain
• D. Left lateral strain

Answer: (A)

In cranial evaluation, a torsion means the sphenoid and occiput rotate in opposite directions around the SBS. The side named for the torsion reflects the direction of the sphenoid’s rotation: left torsion = sphenoid rotated to the left while the occiput rotates to the right.

Seeing the second occurrence of the marker on the left indicates that the landmarks on that side reflect the sphenoid turning left while the occiput turns right. That pattern matches left torsion, so it’s the best fit.

If the pattern were a right torsion, the opposite would be seen (second occurrence on the right). An inferior vertical strain would show vertical, same-direction displacement, and a left lateral strain would show lateral shear rather than opposite-particle rotation of sphenoid and occiput.