Concussions: Causes, Symptoms, and Treatment
By James Beauchamp, D.C.
Motor vehicle accidents and falls are the number one cause of concussion in adults (1). There is frequent confusion about the etiology of headaches after trauma, however. While concussion is almost invariably associated with headaches, neck injuries after whiplash have a prevalence of associated headache symptomatology of 53%, vs. 1 – 4% in the general population (2.) I am going to explain how concussion and cervical headaches occur, describe their symptoms and the medical tests available to document these injuries, and review a reasonable course of treatment that will bring the patient to maximum medical improvement, if not full recovery.
A concussion injury arises when the brain is subject to forces of anywhere from 60G (G = acceleration of gravity) to 160G. This force stretches brain cells, damaging their cell walls and causing a biochemical cascade that is believed to cause concussions distinctive symptoms. These symptoms may or may not include a loss of consciousness, a single seizure, nausea, vomiting, dizziness, sensitivity to light and noise, memory and concentration problems, confusion and drowsiness, among others (3). These symptoms are most prominent for the first few days and weeks following the injury (4). Interestingly, the cause of the amnesia some people experience with concussion is not known (5). However, despite lab work demonstrating that the chemical profile of concussion induced brain trauma typically normalize in less than a month, 10 – 15% of patients continue with chronic post-concussive symptoms (6). Indeed, sometimes the incidence of headache and dizziness can be 90% at 1 month, and 25% after a year or more. These findings cannot be explained away simply upon concussion, or the stigma that even The New England Journal of Medicine impugns upon these patients simply because of “Unresolved issues of compensation and litigation (which) have been associated with persistent symptoms” (7).
A more reasonable view for the persistence of symptoms after concussion resides in the injury threshold differential of the neck and the brain, along with long established neurology. I have previously mentioned that the threshold of concussion varied from 60 – 160G of acceleration applied to the brain. The injury threshold for a mild neck injury is only around 5G. It is unlikely that a patient could sustain an impact to the head orders of magnitude greater than required for a neck injury and NOT experience a concomitant neck injury. Few practitioners are aware of just how similar concussive and whiplash associated disorders may present in the clinical setting. For example, concussion and whiplash symptoms can each include neck pain, headache, dizziness, nausea/vomiting, hearing issues, memory and concentration problems, as well as blurry vision. When these symptoms persist beyond a month, it is most likely a sequela of cervical spine injury (8). Many of these symptoms have complex neurological causes, but ironically, cervicogenic headaches are the most well understood of all. Essentially, headaches from neck trauma such as whiplash are merely referred pain from the neck, analogous to neck pain radiating into the shoulder, back pain radiating into the thigh, or even a brain freeze headache (9).
Both Chiropractic and Osteopathy have a long tradition of successfully treating cervicogenic headaches by addressing the cervical spine. For purposes of documentation, however, the International Headache Society (IHS) contends that diagnostic nerve blocks are the only way to definitively diagnose cervicogenic headaches and it has been argued that radiofrequency neurotomy by an interventional pain management specialist can be an effective treatment. A less invasive and far less expensive approach is simply to establish the diagnosis of cervicogenic headache via history (10, 11) and do a trial course of manual and physical therapy. If the chronic headaches resolve, then the pain was not due to the concussion but to the accompanying neck injury. However, if the headaches are not responsive and are still adversely impacting the patient’s life, then diagnostic nerve blocks are absolutely indicated. If this reduces pain, then treatment with radiofrequency neurotomy is clearly a reasonable approach.
Conclusion: For the vast majority of cases, concussion symptoms will resolve in about a month. If headaches persist longer than that, then it is important to assess and treat the cervical spine, as a whiplash associated cervical spine injury mimicking a concussion is highly probable. Chiropractic and physical therapy have been shown to be up to 73% effective in relieving pain (12). Should this approach fail to generate adequate relief, interventional pain management assessment and treatment is recommended.
Dr. James Beauchamp is a Multi-Specialty HealthCare provider specializing in Chiropractic Care. He is certified in spinal trauma, manipulation under anesthesia, and as an automobile accident reconstructionist. He is also a member of the advisory board for Operation Backbone.
References available by request. Copyright James W. Beauchamp, DC