Ross Hauser, MD

At Caring Medical, we hear from people whose lives have not returned to normal after a concussion. Some are young athletes struggling with school, exercise, or returning to their sport. Others were injured in a car accident, fall, or workplace incident and cannot comfortably resume work. Some have had several head injuries. Others describe years of headaches, dizziness, fatigue, and confusing diagnoses.

These patients need more than a label. They need an explanation of which problems may be contributing to their symptoms and which findings could guide treatment. Persistent symptoms can involve the effects of concussion, a concurrent neck injury, vestibular or visual dysfunction, post-traumatic headache, sleep disruption, autonomic symptoms, and emotional distress. Several can coexist. A normal brain scan does not make the symptoms imaginary, and it does not establish that the neck is their source. (1)

This overview explains those overlapping problems. Our companion article, Post-Traumatic Cervical Instability: Neck Injury, Persistent Symptoms, and Treatment Evidence, provides the detailed discussion of cervical ligaments, neck assessment, imaging, and Prolotherapy.

Video perspective: Remember the neck when evaluating persistent symptoms

In the accompanying discussion, we explain why the neck deserves attention after a head impact. The head and neck move together during many injuries; a rotational or acceleration-deceleration force can affect cervical muscles, joints, or supporting ligaments as well as the brain. This offers a reason to investigate persistent neck symptoms alongside concussion symptoms. It does not establish ligament injury in every person who has been concussed.

The video’s repeated “neck, not brain” wording expresses a stronger conclusion than the evidence supports. The practical message is to avoid overlooking a concurrent cervical problem while continuing to assess other causes of persistent symptoms. The research and patient examples below explain why that distinction matters.

What does “persistent post-concussion syndrome” mean?

A concussion is a traumatic brain injury that can follow a direct blow to the head or force transmitted from a blow to the body. Loss of consciousness is not required. Symptoms can affect thinking, balance, vision, sleep, mood, and physical comfort. A person may feel dazed, develop headaches or nausea, become sensitive to light and sound, or struggle to concentrate. (1)

The Amsterdam concussion consensus uses “persisting symptoms” for symptoms lasting more than four weeks across age groups. This describes a clinical situation requiring further assessment; it does not identify one underlying mechanism. Earlier publications used different time thresholds, helping explain why patients may have received different answers from different clinicians. (1) (2)

A foundational systematic review emphasized that persistent symptoms can reflect several coexisting or confounding problems rather than a single disease process. A later review in Brain similarly questioned whether a broad post-concussion label can sometimes close off investigation of treatable contributors. For example, dizziness deserves assessment for its cause rather than being automatically attributed to the original concussion. (3) (4)

Symptoms

Common concerns include headache or head pressure; dizziness, vertigo, or imbalance; neck pain; blurred vision or difficulty reading; fatigue; nausea; poor sleep; light and sound sensitivity; memory or concentration difficulties; and anxiety or depression. Some people also report lightheadedness on standing, palpitations, exercise intolerance, or digestive symptoms. (5)

The symptom pattern matters more than simply counting symptoms. A headache after prolonged reading, brief spinning when rolling in bed, and lightheadedness when standing may require different investigations even when they all began after the same injury.

Neck clicking, an abnormal-looking posture, or a feeling that the head is difficult to support can be worth discussing, but none by itself diagnoses cervical instability. Likewise, brain fog is not specific to either brain injury or neck injury.

“My tests are normal, but I am still unwell”

Routine CT and MRI are valuable for particular structural problems, but concussion is a clinical diagnosis and often does not produce abnormalities visible on standard scans. EEG addresses electrical brain activity and particular diagnostic questions; a normal EEG does not exclude concussion. Repeated normal tests should lead to a more focused clinical assessment rather than dismissal. (1)

A 2015 study of 52 young patients with persistent symptoms found that later brain imaging had a low diagnostic yield and did not change management in that sample. That finding supports thoughtful selection of imaging, not a rule against further testing when symptoms change or warning signs appear. It also did not show that cervical ligament injury explained those patients’ symptoms. (6)

Some people seek supplements, hormone testing, manipulation, or alternative treatments after becoming discouraged. These choices should be evaluated against the actual clinical problem. Fatigue alone does not establish a vitamin deficiency, endocrine disorder, or cervical cause. Treatment should not depend on an unverified explanation simply because earlier tests were unrevealing.

What if symptoms appear or change months after an injury?

In the video segment beginning around 7:40, we discuss patients who notice neck tightness or other problems after returning to their usual activities. The timing can be a useful part of the history: what was present immediately after the injury, what improved, and what became apparent with school, work, or exercise?

However, symptoms first appearing months or years later should not automatically be assigned to an earlier concussion or a presumed progressive ligament injury. New headache, declining school performance, palpitations, or worsening balance deserves assessment on its own merits. Neck clicking or popping alone cannot confirm instability. A symptom-free interval does not prove that an undetected neck injury was silently progressing.

What if I already have Ehlers-Danlos syndrome or another condition?

People with hypermobile Ehlers-Danlos syndrome may already have pain, joint hypermobility, orthostatic symptoms, or headaches before an injury. Understanding the pre-injury baseline helps distinguish new problems from longstanding symptoms. Generalized hypermobility does not, by itself, diagnose craniocervical instability. The original article’s discussion of these patients remains relevant, with further detail in our Ehlers-Danlos, whiplash, and post-concussion article.

Patient experiences: Why the whole history matters

The following experiences are drawn from accounts previously shared with us and are summarized for clarity. They illustrate questions worth investigating; they are not confirmed explanations of every symptom.

Fatigue, POTS, and difficulty staying upright

One person described chronic fatigue, fibromyalgia, and a diagnosis of postural orthostatic tachycardia syndrome after concussion. They suspected cervical instability but felt unable to obtain a meaningful discussion of that possibility. This history deserves assessment of orthostatic symptoms, medications, sleep, pain, and relevant neurologic and cervical findings. The coexistence of POTS and neck discomfort does not prove that one caused the other.

Dizziness with several different diagnoses

Another person reported multiple concussions, spinal disc problems, migraine, a diagnosis of persistent postural-perceptual dizziness, and abnormal eye movements. Their walking had become unsteady. These findings should prompt careful vestibular, neurologic, and visual assessment. Disc findings alone cannot explain an abnormal eye movement or establish a neck-related cause. We discuss related symptom patterns in our oscillopsia article.

A diagnosis that does not seem to fit

A patient questioned a multiple sclerosis diagnosis after symptoms began following an impact. The symptoms included tinnitus, visual disturbance, and balance problems. The timing understandably raised questions, but an injury history does not invalidate a diagnosis supported by MRI and optic neuritis. These situations call for specialist review of the evidence, not stopping neurologic treatment on the assumption that the neck explains everything.

The athlete whose problems became apparent after returning

A motocross rider described a head-first impact followed by headache and feeling dazed. After resuming racing, the rider developed disabling symptoms, including palpitations, altered sensation, tinnitus, ear fullness, and an unusual feeling of head support. The original account reported improvement with cervical treatment elsewhere. It remains an individual report: it cannot establish which mechanism caused each symptom or predict another person’s response. It also illustrates why a suspected concussion should be assessed before further exposure to impacts.

Dawson’s story: An athlete looking for an explanation

The interview beginning at approximately 40:40 features Dawson, a professional hockey player who describes roughly three years of unexplained symptoms. He reports a racing heart, difficulty sleeping, stomach problems, and persistent neck tension or discomfort. The conversation also refers to previous concussions and an illness following COVID-19, making the history more complicated than a single isolated injury.

Dawson describes extensive testing and the emotional relief of hearing a possible explanation that included his neck. He also discusses symptoms that vary with posture and movement. These details preserve an important patient perspective: being physically fit does not make disabling symptoms less real, and several symptom groups may need consideration together.

The interview took place near the beginning of his evaluation. It is not a completed treatment-outcome report and does not show that Prolotherapy resolved his symptoms or that cervical findings caused his tachycardia, digestive problems, or post-COVID illness. His experience illustrates the search for an explanation; it cannot establish the diagnosis or likely outcome for another reader. The cervical companion explains the mechanical and imaging questions raised in this discussion.

Osvaldo’s story: Improvement, return to daily life, and later recurrence

In Osvaldo’s interview, he describes symptoms beginning after striking his head on a kitchen counter while playing with his children in November 2019. He reports a concussion diagnosis followed by dizziness, vomiting, panic attacks, depression, and severe limitations in daily activity. At his worst, he says he spent months largely confined to bed and could not work.

He later reports substantial improvement during a period of cervical treatment that included Prolotherapy. He describes returning to full-time work, interacting with his children, regaining his appetite and weight, and becoming able to walk and exercise again. These functional changes are an important part of his account, beyond changes in any single symptom.

His story also includes a setback. After doing well for approximately two years, he reports that imbalance, neck pain, and headaches returned. He associates the onset with looking down during a long walk and then becoming dizzy when looking up. That timing is his observation; it does not establish the mechanism of recurrence.

Unlike Dawson’s early evaluation interview, this account includes reported improvement and later recurrence. Both parts matter. It is a patient testimonial, without an independent comparison group or verified outcome measurements, and cannot establish that Prolotherapy caused the improvements or predict another person’s result. The cervical companion includes the fuller account and the limitations of the proposed explanations.

Jonathan’s story: School, work, sensory overload, and hope

In Jonathan’s interview, he describes being struck in the head by a sailboat boom at age 16. He reports a concussion, whiplash, and a C6 fracture, followed by years of neck pain and persistent symptoms. He recalls missing approximately 80 days of his senior year of high school. He nevertheless graduated and later completed college with honors, illustrating how substantial symptoms and academic achievement can coexist.

His account adds a useful description of sensory overload: grocery-store lights and busy displays could provoke a severe headache and make him leave. He also describes pain from ordinarily gentle touch, anxiety, depression, and difficulty sustaining his previous level of work performance as a photographer and creative consultant.

During a period that included cervical injections, exercise, other care, and continued personal support, he reports resolution of neck pain and improvement in memory, concentration, productivity, and quality of life. These are his descriptions of change, not results from standardized cognitive testing or a controlled treatment study.

Jonathan also discusses a bipolar diagnosis that he says was later reconsidered by his treating clinicians. The interview cannot establish whether that diagnosis was correct, whether it changed, or what caused the improvement in mood. It does not demonstrate that cervical treatment cures bipolar disorder or that readers should change psychiatric medication. The cervical companion discusses his experience in greater detail, including the limits of the proposed blood-flow and vagus-nerve explanations.

Headache after concussion: More than one possible contributor

Post-traumatic headache can resemble migraine or tension-type headache. Neck structures can also contribute to headache, and medication overuse, sleep disruption, and other conditions can complicate recovery. Headache location alone rarely settles the diagnosis. (5)

Useful details include when the headache began, whether it is changing, whether reading or exercise provokes it, whether neck movement reproduces it, and whether it changes substantially between lying down and standing. Headache treatment and cervical assessment may both be relevant; neither should automatically replace the other.

New research: Autonomic symptoms may accompany post-traumatic headache early after concussion

In a 2026 study, Garza and colleagues compared 56 adults with acute post-traumatic headache after mild traumatic brain injury with 36 healthy controls. Participants were enrolled when headache onset had occurred 7–56 days earlier. They completed headache diaries and the Survey of Autonomic Symptoms, with assessments at baseline and four- and sixteen-week follow-up visits. (7)

The headache group reported more autonomic symptoms and a greater impact from those symptoms. Common concerns included lightheadedness, dry mouth or eyes, nausea, and cold feet. At baseline, average symptom scores were 2.9 in the headache group versus 0.9 in controls; average impact scores were 8.3 versus 2.1. (7)

Participants whose headaches later improved had significantly lower baseline autonomic symptom impact scores than those whose headaches did not improve. The difference in the number of autonomic symptoms did not reach conventional statistical significance. The useful finding is an association between greater autonomic symptom impact and less headache improvement—not proof of a causal pathway or a validated prediction for an individual patient. (7)

For patients, this supports discussing autonomic-type symptoms alongside headache rather than treating them as unrelated complaints. The study used symptom questionnaires; it did not prove vagus-nerve injury, establish cervical instability as the cause, or test Prolotherapy. (7)

Dizziness, vertigo, vision problems, and a distorted sense of motion

Balance depends on information from the inner ears, eyes, muscles, and joints, together with the brain’s processing of those signals. The inner ear detects head movement and position through specialized sensory organs. It does not maintain balance by “adjusting fluid levels.” Neck sensory signals also help the nervous system interpret head position. (8) (9)

Patients may describe spinning, rocking, floating, swaying, exaggerated movement, or feeling detached from their surroundings. Those descriptions are useful, but they do not identify one cause. Possibilities include positional vertigo, vestibular migraine, persistent postural-perceptual dizziness, visual or eye-movement dysfunction, orthostatic intolerance, and a cervical contribution. (8)

Research describing a proposed vestibular “neuromatrix” suggests that post-concussive vestibular symptoms involve broader brain networks than a simple inner-ear model captures. Such research helps explain complexity; it does not supply a stand-alone diagnostic test or establish that symptoms originate in a damaged ligament. (10)

Different symptom patterns may benefit from different forms of rehabilitation or medical treatment. When neck pain and restricted or painful movement accompany dizziness, assessing the neck can be helpful alongside vestibular and neurologic evaluation. Readers can explore our condition-specific articles on persistent postural-perceptual dizziness and vestibular migraine.

When can a neck injury contribute?

The same accident can transmit forces to the head and neck. Whiplash-associated disorders and concussion can share headache, dizziness, sleep problems, and concentration difficulties. A study of people after motor vehicle collisions supported considering head- and neck-related symptoms together, while also finding that the two symptom patterns were not identical. A concussion does not automatically mean ligament instability, and a whiplash injury does not automatically mean concussion. (11)

A 2024 CARE Consortium study examined 2,163 sport-related concussion injuries. New or worsened neck pain was reported with 47% of injuries. It was associated with longer symptom duration—11.1 versus 8.8 days—and a lower likelihood of symptom resolution within seven days. This supports attention to the neck after concussion, but neck pain was not equivalent to a diagnosis of cervical instability. (12)

Other research has identified neck pain and cervical musculoskeletal or sensorimotor impairments after mild traumatic brain injury. An observational cohort assessed these impairments four weeks to six months after injury. These studies support a cervical assessment when appropriate; they do not show that every persisting symptom has a cervical origin. (13) (14)

At Caring Medical, we consider whether a musculoskeletal neck problem could be contributing when symptoms coexist with persistent neck pain, painful movement, or relevant examination findings. Detailed discussion of joint position sense, ligament injury, dynamic imaging, and the limits of treatment evidence belongs in our cervical companion article.

Lightheadedness, palpitations, nausea, and exercise intolerance

Orthostatic intolerance describes symptoms brought on or worsened by upright posture. After concussion, people may report feeling faint, a racing heart, nausea, or difficulty tolerating exercise. Symptoms alone do not establish POTS or identify the reason for autonomic dysfunction. Blood pressure, heart rate, clinical history, and possible alternative explanations matter.

A study of post-concussion patients highlighted that orthostatic intolerance in this setting can be difficult to recognize and that athletic physiology may complicate assessment. This supports evaluating symptomatic patients rather than assuming that good fitness excludes an autonomic problem. It does not establish vagus-nerve compression as the mechanism. (15)

The original article also included an account from a 16-year-old with vomiting, gastroparesis, substantial weight loss, headaches, and neck discomfort after injuries. That experience is important to preserve: severe digestive symptoms should not be treated as a routine or self-limited part of concussion. Persistent vomiting and weight loss require prompt medical assessment, including evaluation of hydration and nutrition. They cannot be assigned to cervical instability from an online account.

For more background, see our POTS and cervical spine discussion. The same distinction applies there: a proposed connection needs patient-specific evidence.

Why mood, sleep, and stress belong in the discussion

Patients sometimes fear that a referral for psychological support means their symptoms are being dismissed. Persistent pain, disrupted sleep, loss of work or sport, uncertainty, and changes in daily independence can themselves cause substantial distress. Emotional and physical contributors can interact.

A study of 77 adults with persistent symptoms found relationships between fear-avoidance, anxiety, and unexpected symptoms. Its findings argue against automatically equating unusual symptoms with exaggeration. Functional neurologic symptoms, when present, also deserve a positive clinical diagnosis and appropriate care rather than dismissal. (16)

Studies of attachment anxiety and symptom catastrophizing explored additional associations with symptom burden and quality of life. A systematic review and meta-analysis also found a substantial association between persistent post-concussion symptoms and depressive symptoms. These findings support addressing mental health alongside other contributors; they do not mean a person caused their symptoms by worrying. (17) (18) (19)

Sleep disorders, migraine, medication effects, and overlapping illnesses can further complicate the picture. A 2023 clinical review noted overlap with post-COVID symptoms. A new illness may deserve its own assessment rather than being folded into the original concussion diagnosis. (5)

Poor sleep and waking unrefreshed

The video also emphasizes sleep and the frustration of waking tired despite spending enough time in bed. That is useful information to discuss because sleep, pain, headache, mood, and daytime functioning can interact after concussion. The video’s fluid-drainage explanation is a proposed mechanism, however; unrefreshing sleep or feeling better after a nap does not diagnose jugular obstruction or increased intracranial pressure. Sleep symptoms deserve their own assessment rather than being treated as proof of a cervical cause. (5)

Returning to school, work, exercise, and sport

Current guidance favors relative rest during the first 24–48 hours followed by a gradual return to appropriate activity, with symptom monitoring and protection from further injury. Weeks of complete physical and cognitive rest are not the routine recommendation. Return to school or work may require temporary adjustments. Contact, collision, or fall-risk activity requires a separate safety decision and appropriate medical clearance. (1)

An athlete should be removed from play when concussion is suspected and should not return that day. Progression back to sport is individualized; a calendar date alone is not clearance. Children and adolescents also need attention to learning and successful return to school. (1)

Medical clearance and full sporting recovery are different

A matched cohort followed 50 concussed amateur athletes and 50 controls. At one year, 52% of concussed participants reported that they were no longer participating in the same sport at the same competitive level as before injury. Participation has many influences, so this percentage should not be interpreted as the proportion with continuing brain injury or as evidence that concussion prevented all sport for a year. (20)

The corresponding figure in the control group was 24%. Median time to medical clearance in the concussion group was 13 days, whereas median time to return to the pre-injury competitive level was 31 days. These are study observations, not timelines for another athlete’s recovery. (20)

A clinical study of 163 people examined cognitive, visual, balance, vestibular, and cervical findings in relation to delayed recovery. It reinforces the need for a broad assessment rather than relying on one symptom score or one test. (21)

Eighty participants had delayed clearance under the study’s definition. Cognitive symptoms and vestibular examination findings were retained in the multivariable prediction model. The findings support attention to these domains without turning the model into a definitive prognosis for an individual. (21)

What relevant 2026 research adds

A 2026 rehabilitation review describes cervicogenic, vestibulo-ocular, physiologic, and mood-related domains that can guide assessment. A separate 2026 review discusses early, individualized active rehabilitation and return to play. These publications support the current approach of identifying relevant impairments and avoiding prolonged blanket inactivity. They are reviews, not new trials proving a particular injection treatment. (22) (23)

When additional investigation is especially important

Worsening headache, repeated vomiting after a recent injury, increasing confusion or drowsiness, seizure, new weakness, slurred speech, or new severe trouble walking require urgent assessment. Sudden severe head or neck pain with neurologic symptoms should not be assumed to be ordinary cervical instability.

A headache that is markedly worse upright and improves when lying down can raise the question of low cerebrospinal fluid pressure or a CSF leak, although that pattern is not diagnostic by itself. A 2020 report described two collegiate football players with prolonged post-concussion headaches who were diagnosed with intracranial hypotension and improved after blood-patch procedures. Two cases cannot establish how often this occurs or prove that concussion caused the leaks. Low pressure is distinct from intracranial hypertension. (24)

Our intracranial hypotension article discusses this separate issue. Similarly, fainting or neurologic symptoms reproducibly provoked by turning the head need medical evaluation; they should not be repeatedly triggered as a home test.

Prolotherapy

At Caring Medical, our interest in Prolotherapy concerns musculoskeletal pain and suspected ligament-related cervical problems. Dextrose Prolotherapy is intended to stimulate a local tissue response. Our published cervical work includes a narrative review and small observational reports. These sources discuss possible mechanisms and clinical experiences; they do not establish that Prolotherapy treats concussion itself or reliably resolves persistent post-concussion symptoms. (25) (26)

Evidence supporting cervical and vestibular rehabilitation should not be presented as evidence for cervical injections. Decisions about a neck-related treatment require a supported cervical diagnosis, consideration of alternatives, and discussion of risks and uncertainty. Our companion article preserves the fuller treatment discussion and patient videos with that context.

Persistent symptoms deserve continued investigation. The practical question is which contributors are present in this person and how well the evidence supports addressing each one.

This article provides general education and does not diagnose the cause of an individual’s symptoms or replace medical care. Treatment results vary.

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