Muscles of the spine: (Name, Origin, Insertion, Action)
- Iliocostalis group: Superior borders of ribs and iliac crest – Transverse processes of cervical vertebrae and inferior surfaces of ribs – extends vertebral column or bends that to the side and moves ribs.
- Longissimus group: Processes of lower cervical, thoracic, and upper lumbar vertebrae – Mastoid processes of temporal bone, transverse processes of cervical vertebrae and inferior surfaces of ribs – The two sides act together to extend vertebral column and either alone rotates and tilts head or vertebral column to that side.
- Quadratus lumborum: Iliac crest – Last rib and transverse processes of lumbar vertebrae – Together they depress ribs, flex vertebral column and one side acting alone, produces lateral flexion.
- Semispinalis capitis: Spinous processes of lower cervical and upper thoracic vertebrae – Base of skull, upper cervical vertebrae – The two sides act together to extend the neck and either alone, tilts the head to that side.
- Spinalis group: Spinous processes and transverse processes of cervical, thoracic, and upper thoracic vertebrae – The two sides act together to extend vertebral column and either alone, extends neck and tilts head or rotates vertebral column to that side.
- Splenius capitis: Spinous processes of lower cervical and upper thoracic vertebrae – Mastoid process, base of skull, and upper cervical vertebrae – The two sides act together to extend the neck and either alone, rotates and tilts the head to that side.
