The intertransversarii originate and insert on which structures?

• A. Consecutive transverse processes of vertebrae
• B. Consecutive spinous processes of vertebrae
• C. Spinous process of C2
• D. Inferior costal margin

Answer: (A)

Intertransversarii are tiny muscles that connect one vertebra to the next by attaching from the transverse process of a vertebra to the transverse process of the adjacent vertebra. This exact arrangement—origin on a transverse process and insertion on the neighboring vertebra’s transverse process—defines their role. They stabilize the spine and assist with lateral flexion when they contract on one side. They are not attached to spinous processes or to the inferior costal margin, which is why those other structures don’t fit.