What will happen when muscles pass anterior to the spine?

When muscles pass anterior to the spine, they primarily facilitate flexion of the vertebral column. This is because muscles positioned in front of the spine are designed to pull the torso forward, reducing the angle between the body parts, which is characteristic of a flexion movement.

Flexion occurs when the angle at a joint decreases, such as when bending forward at the waist. The primary muscle groups involved in this action include the rectus abdominis and the iliopsoas, which are situated anteriorly to the spine and play significant roles in this motion.

In understanding the context of other movements: extension occurs when the body straightens or moves backward, dorsiflexion refers specifically to the ankle's movement, increasing the angle between the foot and the leg, and plantar flexion involves pointing the toes downward, which does not relate to the spine's anterior musculature. Thus, the action of flexion is directly linked to muscles that pass anterior to the spine.