There’s the old joke: “A man walks into a bar. He says ‘ow’ “.
In my husband’s case, I’m pretty sure that he said not only ‘ow’, but also many other colorful things when he walked full force into a low-hanging pipe in our apartment’s bike room. While it was a rather funny scenario to picture (and I will admit, I did laugh), all humor went out the window when he told me that 12 hours later, he still had a headache and the headache became exceedingly worse when bending over. For those of you without a medical background, that last clause is a red flag that something is seriously wrong. If a patient in your primary care clinic tells you that, you send them to the emergency department (ED) with almost no hesitation. We did go to the ED, and within a few hours left with a diagnosis of concussion.
Concussion is a term that many people use, but usually don’t fully understand its etiology or implications. Until this event, neither did I. Concussion is a colloquial term for a mild traumatic brain injury – most often caused by blunt trauma – that often shows no abnormalities on any imaging such as CT or MRI1. The most common mechanism of injury is the sudden deceleration of the skull2, which results in the brain moving forward to hit the inside of the skull. Despite what Saturday-morning cartoons might depict, the brain does not rattle around inside your head unattached. It is connected to your brainstem and its meninges. Meninges are the coverings that become infected during meningitis (meninge +itis = meningitis). Thus, in addition to smashing itself against your skull, your brain also exerts tensile and rotational forces on its tetherings2. If these forces are too strong, the veins running through the meninges can break, resulting in a brain bleed – one of the main injuries in shaken baby syndrome.
In a simple concussion, these forces cause mitochondrial dysfunction and depletion of intracellular energy stores1. This manifests as global metabolic dysfunction. In layman’s terms: you can’t work your brain without protest in the form of a raging headache, dizziness, and/or nausea. The treatment for concussion is, quite simply, prescription strength boredom. No reading, no looking at screens, no listening to music, and no physical exertion. The patient is instructed to rest in a dark, quiet room while others monitor them for dangerous symptoms like vomiting or seizures. For my husband, who is a graduate student in a computational materials science lab, this meant that his research came to a grinding halt and along with all of his hobbies. This might sound fun to an exhausted and stressed graduate student for about eight hours, but after five days it loses its shine. His concussion was on the mild end of severity with no amnesia and no loss of consciousness, but it has still taken him almost a week to be able to read his email without getting dizzy and nauseous.
So, during this upcoming holiday season, remember to include your brain on the list of things that you’re thankful for. Try doing something nice for it, like wearing a bike helmet or skipping that fifth glass of eggnog. After all, it lets you experience all the fun things in life.
1Pathophysiology of Mild Traumatic Brain Injury. Ch 254: Head Trauma in Adults and Children. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 2011. 7th Edition.
2Concussion. Ch 457: Concussion and Other Traumatic Brain Injuries. Harrison’s Principles of Internal Medicine. 2015. 19th Edition.