Muscle Movements of the Neck and Thoracic Regions

Cervical Region Movements

• Flexion: Occurs through the contraction of longus cervicis, scalenus anterior, and sternocleidomastoid muscles.
• Extension: Caused by the postvertebral muscles.
• Lateral Flexion: Achieved through the contraction of scalenus anterior and medius, trapezius, and sternocleidomastoid muscles.
• Rotation: Results from the combined action of sternocleidomastoid on one side and splenius on the other side.

Thoracic Region Movement

• Rotation: Produced by the unilateral contraction of semispinalis and rotatores muscles, supported by the oblique muscles of the anterolateral abdominal wall.

Lumbar Region Movements

• Flexion: Caused by the contraction of rectus abdominis and psoas muscles.
• Extension: Achieved through the action of postvertebral muscles.
• Lateral Flexion: Occurs through the contraction of quadratus lumborum, the oblique muscles of the anterolateral abdominal wall, and potentially the psoas muscle.
• Rotation: Results from the combined action of rotator muscles and the oblique muscles of the anterolateral abdominal wall.

This quiz covers the muscles responsible for flexion, extension, lateral flexion, and rotation in the cervical and thoracic regions of the spine.