The Neck, the Jaw, and the Headache: How One Region of the Brainstem Connects Them All

The explanation for all three, sitting in the anatomy of the brainstem, has been known for decades. The convergence of cervical and trigeminal sensory pathways in a small region of the brainstem — the trigeminocervical nucleus — is one of the most clinically important pieces of neuroanatomy in musculoskeletal medicine. Understanding it changes how you read a headache, a jaw complaint, a dizzy patient, and a stiff neck. It also explains why treating only the structure that hurts is so often insufficient.

For a deeper look at the neuroscience behind these connections — including the vestibulocerebellar pathway and what two 2025 research papers revealed — see our Evidence Series post: The Brainstem Blueprint.

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The Trigeminocervical Nucleus: Where the Neck Meets the Head

The trigeminal nerve (cranial nerve V) is the primary sensory nerve of the face, scalp, jaw, and — critically — the meninges, the membrane that wraps the brain. Pain signals from the face, teeth, jaw muscles, temporomandibular joint, forehead, and dura all travel via the trigeminal nerve to the brainstem.

At the same time, sensory afferents from the upper cervical spine — the joints, muscles, and fascia of C1, C2, and C3 — travel via the upper cervical dorsal horn into the same region of the brainstem: the trigeminocervical nucleus, also called the trigeminocervical complex.

These two incoming streams converge on the same second-order neurons. The brain, receiving this convergent input, cannot always determine whether the signal came from the trigeminal territory (face, jaw, dura) or the cervical territory (C1–C3 structures). The result is bidirectional referral: neck pain and dysfunction presenting as headache, facial pain, or jaw symptoms — and, in the other direction, jaw dysfunction and facial pain that perpetuates or amplifies cervical sensitisation.

This is not theoretical. A 2025 scoping review by Pankrath and colleagues — the most comprehensive mapping of the TCN to date — examined 83 studies across six major databases and confirmed that the connection is bidirectional: nociceptive activity from either the orofacial/cranial territory or the cervical territory can activate neurons in the other. Of the 83 studies included, 71 (85%) examined the orofacial/cranial-to-cervical direction — reflecting the historical interest of pain and dental neuroscience research — while the reverse pathway is also well documented. The TMJ alone was the subject of 12 studies documenting connections to C1–C3 via the TCN. The authors' clinical conclusion: all three regions — orofacial, cranial, and cervical — should be assessed and managed together in any patient with pain in any one of them. [1]

A 2020 systematic review and meta-analysis by Cuenca-Martínez and colleagues — examining 25 observational studies — found a statistically significant association between neck disability and jaw disability (SMD 0.72; 95% CI 0.56–0.82), with moderate evidence for reduced cervical range of motion and lower pressure pain thresholds in people with temporomandibular disorders compared to controls. The neck and jaw are not independent systems. They are neurally linked at the brainstem, and dysfunction in one reliably affects the other. [2]

Pensri and colleagues' 2025 systematic review and meta-analysis of 77 studies (2551 participants) found consistent cervical musculoskeletal impairments in people with migraine and tension-type headache — including increased forward head posture, reduced cervical flexion-rotation range, and reduced cervical flexor strength and endurance. [3] This is not incidental. These are people whose headache diagnosis does not mention the neck, yet the neck is measurably different in them compared to headache-free controls.

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How the Neck Produces a Headache: Three Mechanisms

Understanding the trigeminocervical nucleus unlocks three distinct but related pathways through which cervical dysfunction produces head pain.

1. Convergent referral from the upper cervical joints

The upper cervical facet joints — particularly C1/C2 and C2/C3 — refer pain reliably into the suboccipital region, the occiput, the temple, and behind the eye. Because these afferents converge with trigeminal afferents at the trigeminocervical nucleus, the brain reads upper cervical joint pain as coming from the head. This is the primary mechanism of cervicogenic headache — a clinically defined condition in which headache is generated by, and referred from, pathology in the cervical spine.

2. Dural tension via the myodural bridge

A 1995 cadaveric study by Hack and colleagues found a consistent fibrous connective tissue bridge between the rectus capitis posterior minor muscle — one of the small suboccipital muscles at the base of the skull — and the posterior atlanto-occipital membrane and the cervical dura mater. [4] This bridge was identified in all five specimens examined. The proposed mechanism: contraction or sustained tension in the suboccipital musculature loads the cervical dura directly. Since the dura is innervated by the trigeminal nerve, dural loading is perceived as head pain. Restricted suboccipital fascia — a finding consistent with the densification model — may perpetuate this dural loading even without active muscle contraction.

3. Central sensitisation via sustained cervical nociception

Persistent nociceptive input from the cervical spine — from facet joints, muscles, fascia, or disc — maintains ongoing activity at the trigeminocervical nucleus. Over time, this produces central sensitisation: a lowered threshold for pain processing throughout the trigeminal and cervical territories. The result is a headache that is not simply referred from the neck but is maintained by a sensitised pain-processing system. This helps explain why people with chronic WAD and chronic cervicogenic headache often have widespread lowered pressure pain thresholds — not just at the neck, but across the head and face as well.

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The Jaw Connection: TMD and the Cervical Spine

The temporomandibular joint, the masticatory muscles, and the orofacial structures are all innervated by the trigeminal nerve. Dysfunction in these structures — pain, restricted opening, myofascial trigger points in the masseter and temporalis — generates afferent input at the same trigeminocervical nucleus where the cervical afferents arrive.

The clinical consequence is bidirectional sensitisation. Upper cervical dysfunction lowers the threshold for trigeminal pain — making jaw structures more pain-sensitive than they would otherwise be. And jaw dysfunction (bruxism, myofascial jaw pain, disc derangement) generates sustained trigeminal input that sensitises the upper cervical territory in return. The two systems wind each other up.

The Cuenca-Martínez meta-analysis finding of SMD 0.72 for the neck-jaw disability association is not small. An effect size in that range indicates a clinically meaningful relationship — meaning that for a practitioner assessing jaw pain, not evaluating the cervical spine is leaving a significant part of the clinical picture unexamined. [2]

The cervical fascia reinforces this connection anatomically. The deep cervical fascial system — described by Natale and colleagues in their 2015 cadaveric study — organises the neck into investing, pretracheal, prevertebral, and visceral layers, with the investing layer ascending through the parotid and masseteric regions. [5] The masseteric fascia and temporalis fascia are continuous extensions of the same deep cervical fascial system. Tension within the cervical fascial compartment is transmitted directly into the masticatory region. Treating jaw pain without addressing the fascial tension in the craniocervical system leaves the mechanical environment unaddressed.

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The Vestibular Extension: When the Neck Causes Dizziness

The story does not stop at headache and jaw pain. There is a third brainstem connection that explains why upper cervical dysfunction can produce dizziness, unsteadiness, and spatial disorientation — and why this is frequently missed.

The vestibular nuclei — the brainstem structures that integrate balance, spatial orientation, and head position — do not operate on vestibular input alone. They receive converging input from three sensory streams: the vestibular apparatus of the inner ear, the visual system, and proprioceptive afferents from the cervical spine. The cervical spine's contribution is significant: the high density of muscle spindles and joint mechanoreceptors in the upper cervical region — particularly at C1 and C2, in the suboccipital musculature — provides moment-to-moment information about head position and movement.

When upper cervical proprioceptive function is disrupted — by joint restriction, myofascial tension, post-whiplash sensitisation, or suboccipital densification — the input arriving at the vestibular nuclei is inaccurate. The vestibular nuclei, integrating an inconsistent signal from the neck with accurate signals from the inner ear and visual system, produce a sensorimotor mismatch: the brain's sense of where the head is in space no longer matches across sensory channels. The result is dizziness, unsteadiness, or a floating, disconnected quality that patients often struggle to describe.

Li and colleagues' 2022 narrative review of proprioceptive cervicogenic dizziness summarises the mechanism: cervical spine proprioceptive receptors — muscle spindles, Golgi tendon organs, and joint mechanoreceptors — are integrated with vestibular and visual systems in the central nervous system. When upper cervical proprioceptive input changes in quality or reliability, dizziness results. [6] This is not inner ear pathology. It is sensorimotor mismatch driven by a cervical spine whose proprioceptive output has been degraded.

A 2025 perspective paper by De Hertogh and colleagues — co-authored by Sue Reid, whose 2015 RCT remains the strongest long-term clinical evidence for cervicogenic dizziness treatment — maps the pathway in greater anatomical detail. [7] Cervical proprioceptive afferents travel to the central cervical nucleus and project from there to the cerebellum and reticular formation. The cerebellum — which processes vestibular, visual, and cervical proprioceptive signals simultaneously — acts as a comparator: when all three channels agree, spatial orientation is stable; when one is degraded, the mismatch produces dizziness. Critically, the cerebellum can compensate for vestibular loss using cervical proprioception alone — but when it is the cervical signal that is inaccurate, this redundancy fails. In persistent cases, De Hertogh and colleagues also describe central maladaptation: the brain's sensory reweighting becomes dysregulated, visual dependence increases, and symptoms persist beyond the original peripheral trigger. This is why some cervicogenic dizziness presentations require sensorimotor rehabilitation alongside structural treatment of the cervical source.

Clinically, this explains why the same patient who has cervicogenic headache — driven by upper cervical joint and fascial dysfunction — may also report dizziness on head movement, difficulty with balance, and a tendency to feel unsteady in visually complex environments. These are not three separate problems. They are three outputs of the same dysfunctional cervical system, mediated through two different brainstem convergence zones: the trigeminocervical nucleus for pain, and the vestibulocerebellar system for spatial orientation.

A 2015 RCT by Reid and colleagues — 86 patients with chronic cervicogenic dizziness, followed for 12 months — demonstrated that manual therapy directed at the cervical spine produces significant reductions in dizziness frequency and Dizziness Handicap Inventory scores, with effects maintained at 12-month follow-up. [8] The treatment is not directed at the inner ear. It is directed at the cervical spine, because that is where the dysfunction originates.

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The Fascial System Across All Three Territories

The trigeminocervical nucleus and the vestibular nuclei explain the neural pathways. The fascial system explains the mechanical one.

The craniocervical fascial system — the investing layer of the deep cervical fascia, the suboccipital fascial compartment, the posterior cervical retinacular sheath, and its extensions into the masseteric and temporal regions — is a single continuous mechanical environment. Densification within this system does not respect the boundaries between "neck pain," "headache," "jaw pain," and "dizziness." A restriction in the posterior suboccipital compartment can load the dura via the myodural bridge, alter the mechanics of the upper cervical joints (driving trigeminocervical sensitisation), and impair the proprioceptive output of the suboccipital musculature (disrupting vestibular integration) — all simultaneously.

This is why a patient with chronic headache, jaw pain, and dizziness presenting together is not a puzzle requiring three specialists. It is a pattern that points to the upper cervical fascial and joint system as the common source. The cervical fascia described by Natale and colleagues [4], the suboccipital anatomy documented by Hack and colleagues [3], and the brainstem convergence zones documented in the neurophysiology literature are all describing the same clinical reality from different vantage points.

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What the Research Supports for Treatment

Two systematic reviews are directly relevant here. Chaibi and Russell's 2012 review of manual therapies for cervicogenic headache found that manipulation and mobilisation produce significant reductions in headache frequency, intensity, and disability — with effect sizes comparable to prophylactic medication. [9] Racicki and colleagues' 2013 review confirmed that multimodal manual therapy combined with exercise — particularly deep cervical flexor training — produces superior outcomes to either intervention alone. [10]

These findings translate directly to the jaw and dizziness presentations, because the target structures are the same: the upper cervical joints, the suboccipital musculature, and the fascial system that invests them.

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What This Means for You

If you have headaches that seem to start at the base of the skull or behind the eye, the upper cervical spine is worth assessing — regardless of what your headache diagnosis says. The convergence of cervical and trigeminal afferents at the trigeminocervical nucleus means that headache can be generated and maintained entirely by cervical dysfunction, with no pathology visible on head imaging.

If you have jaw pain, clicking, or tension that doesn't fully respond to dental treatment or splinting, the cervical spine may be contributing. The Cuenca-Martínez finding of a clinically significant neck-jaw disability association [1] means that cervical assessment is not optional in TMD — it is a core part of a comprehensive evaluation.

If you experience dizziness, especially with head movement or in busy visual environments, and inner ear testing has been unremarkable, the upper cervical spine and its proprioceptive output to the vestibular nuclei should be assessed. Cervicogenic dizziness is not a diagnosis of exclusion made reluctantly when everything else is normal — it is a mechanistically understood condition with a sound evidence base for manual therapy treatment.

If you have a combination of these symptoms, the likelihood that a single upper cervical source is contributing to all of them is high. The brainstem connections are not incidental — they are the reason a single region of the cervical spine can drive pain in the head, tension in the jaw, and unsteadiness in the body simultaneously.

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Want to discuss whether your headache, jaw pain, or dizziness has a cervical component?

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