The three most important muscles in your neck - Workshop Summary

Nick Hodgson discussed three crucial neck muscles—the rectus capitus posterior minor, rectus capitus posterior major, and oblique capitus inferior – detailing their anatomy, actions, and shared innervation by the suboccipital nerve, while explaining the body’s tensegrity principles and the concept of the spinal cord being suspended, not floating. Hodgson reviewed multiple research papers confirming the existence and normal anatomy of the "myodural bridge," a connective tissue link between these suboccipital muscles and the spinal dura mater, which is implicated in cervicogenic headaches and stabilizing the dura against dural infolding and movement, contributing to proprioception and cerebral fluid dynamics. The clinical importance of these myodural bridges, whose abnormalities are linked to cervicogenic symptoms, was highlighted, leading Nick Hodgson to suggest that therapy targeting these muscles and the upper cervical spine, such as with a 3D energy gun, can be beneficial.

Details

• Three Important Neck Muscles: Nick Hodgson introduced a discussion on three important neck muscles: the rectus capitus posterior minor, rectus capitus posterior major, and oblique capitus inferior. He detailed the anatomy and action of the rectus capitus posterior minor, noting its connection between the C1 (atlas) and the occiput, its role in head extension, head posture, and stability, and its innervation by the suboccipital nerve. He also described the rectus capitus posterior major, which connects C2 (axis) to the occiput, extends and rotates the head, and shares the same nerve supply, as well as the oblique capitus inferior, which rotates the head to the ipsilateral side and contributes to stabilizing the head and the C1/C2 joint.

• Myodural Bridges and Spinal Cord Suspension: Nick Hodgson explained the anatomy of the three muscles, including how they form part of the suboccipital triangle, and emphasized understanding the human body based on tensegrity principles, where the spinal cord is suspended, not floating, inside the spinal column. He introduced 11 research papers supporting the existence of a connective tissue bridge, later called the "myodural bridge," between these suboccipital muscles and the spinal dura mater. Early research from 1995 observed this connective tissue bridge in every specimen between the rectus capitus posterior minor and the dorsal spinal dura at the occiput C1 junction, suggesting its role in resisting dural movement toward the spinal cord and preventing dural infolding during head and neck extension.

• Clinical Relevance of Myodural Bridges and Cervicogenic Headache: Nick Hodgson reviewed several studies confirming the anatomical connections between suboccipital musculature and the spinal dura mater, asserting this is part of the normal anatomy. Research suggested these myodural bridges, particularly the connection involving the rectus capitus posterior minor, may offer anatomical and physiological explanations for the cause of cervicogenic headaches and the efficacy of manipulations in treating them. The oblique capitus inferior myodural bridge, confirmed in a 2013 study, was also noted to potentially monitor dural tension (proprioceptive function) and prevent dural infolding (biomechanical role), with alterations in dural tone potentially contributing to certain clinical symptoms.

• Further Evidence and Biomechanical/Physiological Roles of Myodural Bridges: Nick Hodgson presented multiple studies that solidified the existence and function of the myodural bridges, including those involving the rectus capitus posterior major and a systematic review that provided a strong level of evidence for connections from all three muscles to the dura mater. Further investigation suggested the myodural bridge complex, particularly the tissue length complex related to the rectus capitus posterior minor, stabilizes the dura during neck extension and can reduce dural bulging into the spinal canal during hyperextension. The myodural bridge is also thought to have functions related to proprioception, maintaining the subarachnoid space, and affecting the dynamics and circulation of cerebral fluid. The myodural bridge is a collagenous soft tissue connection that effectively transfers tensile forces from the involved muscles and ligaments to the spinal dura mater during head movement, maintaining the central alignment of the spinal cord and dural sack.

• Conclusions and Therapeutic Implications: Nick Hodgson concluded that there are well-proven connections between the rectus capitus posterior minor, rectus capitus posterior major, and oblique capitus inferior muscles to the spinal dura mater. Researchers have repeatedly proposed both important biomechanical and neurological roles for these connections, noting that abnormalities in them are connected to cervicogenic symptoms and other signs of dural tension. He suggested that effective therapy, specifically recommending the 3D energy gun, can benefit those with issues in these muscles and the upper cervical spine.