More can be done than simply medicating a headache says Dr. Joel Dixon
Headaches are among the most prevalent health-care disorders affecting North Americans. The most common type of headache is a tension headache.
Tension-type headaches affect 30 to 80 per cent of the general population (women are 2x’s more likely to be afflicted) with the average individual experiencing tension headaches twice a month. Three per cent of the population suffer from chronic daily tension headaches.
Tension-type headaches are usually classified as either episodic or chronic based on the frequency. According to the International Headache Society (IHS), episodic tension headaches occur less than 15 days per month; whereas, chronic tension-type headaches occur more than 15 times a month, for at least six months.
Tension headaches are characterized as a squeezing or vice sensation that is felt bilaterally on the front, sides or top of your head. Patients with tension headaches tend to notice that their symptoms present later in the day, are associated with stressful events and affect a person’s ability to concentration. Research has shown that the intensity of tension headaches increases with the frequency.
Tension headaches differ from migraines in that they are not paired with neurological impairments, such as: vision, balance or strength deficits. Patients usually do not have severe sensitivity to light/sound, nausea and vomiting.
There is no definitive cause or family predisposition for having tension-type headaches. Tension headaches are usually associated with inadequate rest, poor posture, emotional or mental stress, depression, fatigue and overexertion.
Suboccipitals and the Myodural Bridge
One proposed mechanism for the cause of tension-type headaches that has gained a lot of traction in recent years in the relationship between the suboccitipal muscles and a myodural bridge. Before we continue, let’s cover some basic anatomy.
The suboccipitals are four small muscles that are located on either side of the base of your skull. The four muscles are rectus capitis posterior minor (RMAJ), rectus capitis posterior major (RMIN), inferior oblique and superior oblique. The suboccipital muscles are responsible for fine motor control. Smaller muscles like the subocciptials tend to have a lot of sensors, such as muscle spindles that detect the rate in which a muscle changes its length or position.
The other proposed mechanism of the suboccipitals is that they have been shown to modulate the tension of the myodural bridge. The myo (muscle — suboccipital) dura (outer most pain sensitive lining covering the brain and spinal cord) bridge is a ligament like structure that attaches the suboccipital muscles to the dura. The bridge provides passive and active anchoring of the spinal cord. It also prevents the dura from buckling inwards when you extend your head. Conversely, it prevents compression of the spinal cord when you bend your head forward.
When there is significant trauma to the neck, studies have shown that the cross-sectional area (CSA) of the suboccipitals decreases (atrophy). Research has also shown that there is a correlation between the decreased CSA of RMAJ and RMIN in individuals with chronic tension-type headache.
Tension Headaches and Post-Concussive Symptoms
A recent article published in the American Journal Neuroradiology looked at the CSA of the RMIN in individuals with post-concussive symptoms. The researchers found that a smaller CSA was associated with increased symptom severity, longer recovery time, poor verbal memory performance and increased prevalence of headaches. The authors concluded that: “Given the unique connection of this muscle to the dura, this finding may suggest that pathology of the myodural bridge contributes to symptoms and prognosis in concussed individuals.”
The initial pharmaceutical Intervention for tension headaches is over the counter pain medication. Pain medication, muscle relaxants, antidepressants, blood pressure medication and antiseizure medication may also be prescribed in a preventive, daily nature. Patients should be informed that taking daily medication for headaches can lead to medication overuse headaches.
Therapeutic Interventions for Tension Headaches
For chronic tension-type headaches the Canadian chiropractic association’s clinical practice guidelines (CPG) recommend low force mobilization of the head and neck. The CPG also mentions a high quality study that found spinal manipulative therapy (adjustments) to be effective for chronic tension type-headaches. It postulated that the myodural bridge provides a mechanical explanation for the efficacy of massage and manipulative treatments with tension and cervicogenic headaches. Other therapeutic interventions include deep neck flexor endurance exercises, as well as suboccipital rehab exercises.
If you have any questions regarding any of the information provided, please visit sportsrehabandwellness.ca.
Dr. Joel Dixon is the newest chiropractor at New Hamburg Wellness Centre and is a certified complete concussion management practitioner.