Rectus posterior major capitis muscle
Musculus rectus posterior major capitis
Rectus capitis posterior major is a suboccipital muscle that widens upwards from the spine of the axis to the occipital bone.
At a glance
- English
- Rectus posterior major capitis muscle
- Latin (TA2)
- Musculus rectus posterior major capitis
- System
- Muscle
- Region
- Neck
- Side
- Paired, left and right
About the rectus posterior major capitis muscle
Rectus capitis posterior major is one of the four suboccipital muscles, the small, deep group just below the back of the skull. Its Latin name describes it as the bigger straight muscle at the back of the head. It lies deep to semispinalis capitis and forms the upper inner side of the suboccipital triangle, with the oblique muscles forming the other sides.
Its pointed tendon springs from the axis spine. Widening as it climbs, it runs upwards and outwards to the inferior nuchal line, on its outer half, and the occipital bone just below it. Because the left and right muscles diverge as they rise, they leave a triangular gap between them in the midline, in which the smaller rectus capitis posterior minor can be seen.
The muscle extends the head on the neck and turns the face towards the same side, using both the atlanto-occipital and atlanto-axial joints. Like the other suboccipitals, it is short and rich in muscle spindles and is thought to help sense and fine-tune head position. A band of connective tissue linking it to the dura mater of the upper spinal canal has been described; it may help keep the dura from buckling during head movement.
It is supplied by the suboccipital nerve, the dorsal ramus of the first cervical nerve, and receives blood from the vertebral and occipital arteries. Its connection with the dura has been proposed as one way in which tension in the upper neck could give rise to headache, though this is still debated.
Attachments, action and supply
- Origin
- Spinous process of the axis (C2).
- Insertion
- Inferior nuchal line, outer half, and the occipital bone just below it.
- Action
- Extends the head and turns it to the same side.
- Nerve supply
- Suboccipital nerve (dorsal ramus of C1).
- Blood supply
- Vertebral and occipital arteries.
Anthromica
See the rectus posterior major capitis muscle where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
