Unlocking the Potential Benefits of Chiropractic Care for Concussion and Post-Concussion Syndrome
Mild traumatic brain injuries, more commonly referred to as concussions, are a concerning public health issue in the United States. With an estimated 3.8 million cases occurring annually, most patients typically recover within 7 to 10 days. However, approximately 10% to 15% of individuals experience persistent symptoms that can last for weeks, months, or even years after the initial injury, a condition known as post-concussion syndrome (PCS). PCS is officially recognized when symptoms persist beyond 4 to 12 weeks.
Traditionally, PCS has been attributed solely to brain injury, causing alterations in brain biochemistry, neurophysiology, and metabolism. But emerging research suggests that the cervical spine, comprising the neck and upper back, may play a significant role in PCS. In some cases, cervical spine injury might be the primary driver behind PCS symptoms.
Studies have revealed a striking overlap in the signs and symptoms of mild traumatic brain injury, PCS, and whiplash injuries to the cervical spine. A 2015 study titled "The Role of the Cervical Spine in Post-concussion Syndrome" published in The Physician and Sportsmedicine noted that cervical spine injury can lead to symptoms commonly associated with concussions, including headaches, dizziness, loss of balance, nausea, visual and auditory disturbances, reduced cognitive function, and more.
The study proposed a mechanism where a "concomitant low-grade sprain-strain injury of the cervical spine occurring concurrently with significant head trauma" contributes to PCS. It emphasized that any significant impact or acceleration/deceleration of the head is likely to result in some degree of injury to the cervical spine. Moreover, it suggested that the prevalence of headaches and dizziness in concussion-type injuries might be linked to concomitant whiplash injuries sustained at the same time.
The overlapping symptoms between concussion and cervical injury are evident, as both conditions can lead to:
Common Symptoms of Concussion
- Headache
- Dizziness
- Nausea/vomiting
- Blurred vision
- Sensitivity to light
- Memory problems
- Balance problems
- Confusion
- Irritability
- Fatigue
Common Signs and Symptoms of Whiplash Cervical Injury
- Headache
- Neck/shoulder pain
- Reduced/painful neck movements
- Nausea/vomiting
- Dizziness
- Unsteadiness
- Vision problems
- Memory problems
- Ringing in ears
- Feeling slowed down
- "Don't feel right"
- Nervous/anxious/irritable
- Sadness/more emotional
- Fatigue/low energy/drowsiness
- Trouble falling asleep
- Reduced/painful jaw movements
- Numbness, tingling, or pain in arm or hand
- Numbness, tingling, or pain in leg or foot
- Difficulty swallowing
- Lower back pain
Given the similarity in symptoms, it's highly likely that the forces necessary to cause a mild traumatic brain injury would also damage the soft tissues of the cervical spine. Both anatomically and physiologically, the cervical spinal cord is connected to the brainstem and brain, with various structures in the brainstem receiving inputs from cervical spinal afferents.
This neural connection plays a crucial role in various functions, including balance, posture, eye stability/movements, and nociception (perception of pain). "Cervicogenic vertigo" refers to reflex pathways from upper cervical spine afferents to brainstem structures responsible for balance. Aberrations in cervical ocular and vestibular reflexes can lead to balance disturbances and symptoms associated with PCS.
Research has also recognized "cervicogenic headache" for decades, highlighting the contribution of cervical spine dysfunction to headache symptoms.
Several studies provide compelling evidence of the connection between cervical spine injuries and PCS:
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A 1990 study revealed that specific manual therapy on the neck led to a significant reduction in headaches in patients suffering from post-traumatic headache. This therapy was shown to have a "specific effect" in reducing post-traumatic headaches and suggested that symptoms like dizziness, visual disturbances, and ear issues could be part of a cervical syndrome.
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In 1994, a study measured cervical musculoskeletal function in post-concussion headache patients and found distinct dysfunction in the upper cervical segmental joint, endurance in neck flexor muscles, and tight neck musculature compared to a control group. This led to the recommendation of a "precise physical examination of the cervical region" in patients with persistent headaches following concussion.
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A 2014 randomized controlled trial demonstrated that a combination of cervical spine and vestibular physiotherapy decreased the time required for medical clearance to return to sports in patients with persistent symptoms of dizziness, neck pain, and headaches following a sport-related concussion.
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A 2015 study showcased the favorable outcomes of chiropractic cervical spine management, including spinal manipulation, in patients diagnosed with PCS. The study emphasized that traditional rest-based management was outdated and less effective than skilled manual therapy aimed at addressing cervical spine dysfunction.
Furthermore, research suggests that cervical spine injuries can lead to abnormal neural input into the brainstem and brain, which can be responsible for the symptoms commonly associated with PCS. Therefore, differentiating between cervical injury and concussion is crucial, as treatment methods differ significantly.
Clinical tests have been developed to help differentiate between the two conditions. Some of these tests include:
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Cervical Joint Repositioning Error Test (JPET): This test assesses the ability to return the head to a neutral position after maximal rotation or flexion/extension with eyes closed.
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Smooth Pursuit Neck Torsion Test (SPNTT): This test involves tracking a moving object with the eyes while actively rotating the neck, helping identify vertigo due to neck disorders.
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Head-Neck Differentiation Test (HNDT): This test checks if the head can remain still while the body is rotated to provoke symptoms, indicating cervicogenic vertigo.
In conclusion, research suggests that cervical spine injuries often contribute to PCS symptoms, and effective treatment methods include addressing cervical spine dysfunction. The evidence supports a shift away from traditional rest-based management of PCS towards more active and targeted approaches to address cervical spine issues. Therefore, patients experiencing PCS symptoms should be referred for cervical spine evaluation and treatment, with chiropractic care and manual therapy playing a crucial role in their recovery.
Written by Dr Diego Caban for OrthoTrust