| Spinalis | |
|---|---|
| Deep muscles of the back. (Spinalis dorsi visible at center. Other spinalis muscles not visible.) | |
| Latin | musculus spinalis |
| Gray's | subject #115 399 |
| Origin | spinous process Thoracis: Upper lumbar and lower thoracic vertebrae. Cervicis: Ligamentum nuchae & spinous process of C7. |
| Insertion | spinous process Thoracis: SP of upper thoracic vertebrae. Cervicis: SP of cervical vertebrae except C1. |
| Artery | lateral sacral artery |
| Nerve | posterior branch of spinal nerve |
| Actions | Laterally: Flex the head and neck to the same side. Bilaterally: Extend the vertebral column. |
| Antagonist | Rectus abdominis muscle |
The spinalis is the portion of the erector spinae, a bundle of muscles and tendons, located nearest to the spine. It is divided into three parts.
Contents |
The Spinalis dorsi, the medial continuation of the Sacrospinalis, is scarcely separable as a distinct muscle.
It is situated at the medial side of the Longissimus dorsi, and is intimately blended with it; it arises by three or four tendons from the spinous processes of the first two lumbar and the last two thoracic vertebrae: these, uniting, form a small muscle which is inserted by separate tendons into the spinous processes of the upper thoracic vertebræ, the number varying from four to eight.
It is intimately united with the Semispinalis dorsi, situated beneath it.
The Spinalis cervicis (Spinalis colli) is an inconstant muscle, which arises from the lower part of the ligamentum nuchæ, the spinous process of the seventh cervical, and sometimes from the spinous processes of the first and second thoracic vertebrae, and is inserted into the spinosus process of the axis, and occasionally into the spinous processes of the two vertebrae below it.
The Spinalis capitis (Biventer cervicis) is usually inseparably connected with the Semispinalis capitis.
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.
