Semispinalis origin is on which anatomical feature?

Semispinalis origin is on which anatomical feature?

• A. Transverse processes of several vertebrae
• B. Spinous processes of several vertebrae
• C. Anterior crests of ilium
• D. Costal cartilage

Answer: (A)

Semispinalis is part of the transversospinalis group, so its fibers start from the transverse processes of several vertebrae and climb upward to insert on the spinous processes of vertebrae several levels above. This design—origin on transverse processes and insertion higher up on the spine—enables it to help extend the spine and assist with contralateral rotation. The other options don’t fit because the muscle does not originate from spinous processes, the anterior iliac crest, or costal cartilage, which are associated with other muscles or regions (iliacus or abdominal/rib cage muscles, respectively).

Semispinalis is part of the transversospinalis group, so its fibers start from the transverse processes of several vertebrae and climb upward to insert on the spinous processes of vertebrae several levels above. This design—origin on transverse processes and insertion higher up on the spine—enables it to help extend the spine and assist with contralateral rotation. The other options don’t fit because the muscle does not originate from spinous processes, the anterior iliac crest, or costal cartilage, which are associated with other muscles or regions (iliacus or abdominal/rib cage muscles, respectively).