The occipitoatlantal (OA) joint is an important component among the complicated anatomy of the suboccipital region. A combination of dysfunction in the motion and positioning of the joint, abnormal tension of nearby musculature and ligamentous structures, and compression of significant cranial and spinal nerves is thought to contribute to pain in certain types of headaches.
1 Osteopathic manipulative treatment applied to this region may improve joint biomechanics, autonomic tone, and circulation of the region.
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The OA joint is composed of the 2 condyles of the occipital bone and the superior articular facets of the atlas, forming a pair of synovial joints.
2(pp736-737) Notable connective tissue structures that connect the 2 bones are the anterior and posterior occipitoatlantal membranes. These 2 membranes fuse with the joint capsules, and the posterior membrane also fuses with the spinal dura. Three of 4 suboccipital muscles—the rectus capitis posterior major and minor and the obliquus capitis superior—cross the OA joint.
2(pp744-745) Together, these muscles serve in a patient's proprioception and postural function, and they may also aid in stabilization.
3 Furthermore, the rectus capitis posterior minor muscle, which originates from the posterior arch of the atlas and inserts onto the inferior nuchal line of the occipital bone, has been shown in some individuals to contain additional connective tissue attaching to the posterior occipitoatlantal membrane, forming what is known as the myodural bridge.
2(pp744-745) Innervation to the OA joint is supplied by the ventral ramus of the C1 cervical nerve.
2(pp744-745)