Headache

Concussion Evaluation:

Not all Headaches are Created Equal

David Wang MD, MS

Concussions are clearly identified more frequently as awareness has increased over the past several years.  This has been well documented in reported concussion numbers as well as emergency room visits.

We will focus here on one very important issue that is ubiquitous in the concussion arena.  This issue is headaches.  All too often I see a patient who has suffered a blow to the head followed by a headache as absolute proof of concussion.  When this thought process is used the patient can be over treated for concussion where the concussion may have resolved and another cause for the headache exists, or a concussion may not even have occurred at all.  In concussion management there are countless scenarios involving headaches.  Patient reported headaches may not be concussion headaches, headaches may have existed prior to the injury, the headaches may change from one variety to another, or multiple types of headaches coexist in the same patient.

A useful mnemonic to think of in concussion headache management is HEADACHE.

Headaches Other (Migraine, Tension) – Migraine headaches are vascular headaches and are classically described with a neurologic prodrome (often ocular) followed by a severe unilateral headache that is throbbing in nature.  These headaches can be accompanied by significant photophobia and nausea and often require sleep to resolve the issue.  It is felt that these headaches can be triggered by trauma such as a concussion.  These headaches also occur more commonly in females and usually present themselves around puberty which often coincides with when more females are involved in organized sports.

Like cervical headaches tension headaches are extra-cranial muscular headaches described as squeezing in a band-like pattern around the head.  These headaches can be secondary to multiple etiologies such as emotional stress as well as eye and neck strain.

Eye (Oculomotor) headache – One of the most common processes to be affected by concussion is the oculomotor system.  The oculomotor system traverses most of the brains neural tissue.  As the force is transmitted to the brain the strain often occurs in commonly affected areas. Although a multitude of areas may succumb to the strain it is likely that the visual system will be affected.  Screening tests for these deficits are often found in the well documented VOMS oculomotor tests.  Typically, these deficits result in headaches that are induced by visual stimuli such as focusing and/or tracking.  These headaches are often frontal in nature.

Axial spine (Cervical) headache – The mechanics of a concussion are forces being transmitted to the brain usually through an acceleration/deceleration mechanism.  For this to occur the cranium is often violently rotated or moved in a linear fashion. To move the cranium the cervical structures must also be involved.  Violent motions of the cervical structures can lead to muscular and fascial injuries and less commonly boney injuries.  Muscular injuries of the cervical region can result in headaches and even dizziness.  These headaches typically originate in the posterior cranial region such as the nuchal ridge.  They wrap around anterior towards the temples and are generally described as squeezing in nature.  In my experience these are also the headaches noted upon arising in the morning.

Drug (Rebound) headache – Many concussion patients are given over the counter medications for pain and headaches.  If this process is repeated on a regular basis for over a few weeks there can be a medication induced dependence.  This dependence can manifest itself as headaches when the medication is not taken.  These headaches then improves when the medication is taken again.  These headaches are global in nature.

Anxiety contribution to headache – One of the issues that significantly complicates concussion management are mental health issues.  Depression and anxiety are commonly diagnosed in teenagers today.  When present prior to the concussion they can be seen to worsen following the injury.  In some cases when prolonged symptoms are present anxiety and depression can be a result of the concussion experience.  The concussion experience not only includes the concussion itself but the lifestyle consequences that can accompany the injury.  These patients can fixate or amplify many of their symptoms including headaches.

Concussion headache – This headache is obviously very common.  It is felt to be secondary to the energy deficit that occurs in the brain after a concussion.  In this “impaired state” exertion and cognition may tax the brain enough to result in a headache.  This headache features a global/vertex distribution often exacerbated by cognition and stimulation. The concept of an energy deficit headache is difficult to study but unless an extreme head injury has occurred the amount of energy deficit is likely to be very small and not increase the normal homeostasis energy demands by any significant amount. A full day of normal brain functioning requires 23 W of energy while a normal one-hour workout uses approximately 100 W.  Even if brain energy demands doubled after injury it would represent a small portion of total body energy expenditure.  This headache may very well represent the brains attempt to indicate that there is a perturbation from the normal brain function/environment.  The brain itself does not have any pain receptors and may perceive changes in function as pain which is global in nature as the brain is unable to localize these changes.

Hemorrhage (Subdural, Epidural, Inter-parenchymal) – Thankfully these headaches are uncommon in sports related concussions, but these are also the headaches that need to be rapidly identified as they are life threatening.  These are global headaches that typically worsen over time with declining neurologic function.  Repeated vomiting, slurred speech, and obtundation are often seen.  These headaches include epidural hepatomas, subdural hepatomas, and inter-parenchymal hemorrhage.  As previously noted, these represent a medical emergency.

Also:

HORMONES: as hypopituitarism is not uncommon following head injury with growth hormone deficiency most common.  Low growth hormone can mimic many concussive symptoms especially memory loss and decreased energy.

Extra-cranial headache – These headaches are secondary to injury outside on the skull. They do consist of tension and cervical headaches.  They also are secondary to soft tissue injury directly associated with the location of the blow to the head.  In some cases, a laceration or bruise is noted acutely but in other more insidious cases occur secondary to scar tissue and probable superficial nerve involvement.  These headaches are palpable in the location of the injury and are often described as sharp and stabbing in nature.

As noted above there are a multitude of headaches that must be considered when caring for patients who have suffered a concussion.  It is not so simple that all these headaches are concussion headaches and with a better awareness of the types of headaches that may exist one can better care for these patients.  The treatment plan can differ greatly between the different types of headaches.  For instance, oculomotor headaches and cervical headaches respond well when appropriately therapies are prescribed.  Anxiety headaches may require treatments such as psychotherapy.

When caring for concussion patients we hope the HEADACHE mnemonic reminds us of the variety of issues that could be present when evaluating those with headaches.  At Comprehensive Sports Medicine we have had many years sorting out these types of headaches so that we can institute an appropriate treatment plan.