The rectus capitis posterior major is the larger of the two rectus capitis posterior muscles, forming the medial part of the suboccipital triangle floor. It arises from the spinous process of the axis and fans superolaterally to the inferior nuchal line. Together with the three other suboccipital muscles it forms the suboccipital triangle, bounded by the obliquus capitis superior, obliquus capitis inferior, and rectus capitis posterior major, with the vertebral artery and suboccipital nerve occupying the triangle floor.
| Origin | Spinous process of the axis (C2) |
|---|---|
| Insertion | Lateral part of the inferior nuchal line of the occipital bone and the bone between the nuchal line and the foramen magnum |
| Nerve Supply | Suboccipital nerve (posterior ramus of C1) |
| Blood Supply | Vertebral artery; Occipital artery |
| Actions | Extension of the head at the atlantooccipital joint; Ipsilateral rotation of the head at the atlantoaxial joint |
|---|
A dense myodural bridge of connective tissue links the rectus capitis posterior major and minor directly to the dura mater of the spinal cord at the craniocervical junction. This anatomical connection, demonstrated in multiple cadaveric studies, has been proposed as a mechanism by which suboccipital muscle contraction and myofascial restriction can directly tension the dura, contributing to cervicogenic headache, dural tethering, and Chiari-related symptoms. Suboccipital muscle inhibition techniques and dry needling of these muscles form the basis of manual therapy for cervicogenic headache.
Palpate just inferior to the external occipital protuberance in the suboccipital region, medial to the obliquus capitis superior and superior to the posterior arch of C1. Best assessed with the patient prone and the head gently flexed to relax the overlying semispinalis capitis.
Acute or chronic strain of the rectus capitis posterior major and its suboccipital neighbours from whiplash, sustained head posture, or repeated end-range head rotation produces suboccipital pain, restricted upper cervical rotation, and referred pain to the vertex and frontal region mimicking tension-type headache.
Via the myodural bridge, suboccipital muscle hypertonicity and myofascial trigger points in the rectus capitis posterior major can directly influence dural tension and produce cervicogenic headache characterised by unilateral pain radiating from occiput to frontal region, managed with suboccipital release, dry needling, and manual therapy.
