The interspinales are a set of deep muscles of the back. They are generally considered absent from the thoracic region.
- Attachments: Originate from the spinous process of cervical and lumbar vertebrae. The fibres ascend and insert onto the spinous processes of the vertebrae above.
- Actions: Contributes to extension and rotation of the vertebral column. Also stabilises the vertebrae.
- Innervation: Posterior rami of the spinal nerves.
- Blood Supply:
- Cervical region – vertebral, deep cervical, occipital, and transverse cervical arteries .
- Lumbar region – lumbar arteries.