Headache

Headache is a particularly troublesome form of regional pain. The World Health Organization has endorsed a study which reported that the world-wide prevalence of headache in the general population is 46 percent, with a moderate preference for females (1). Of course, headache is not a single entity, but rather a generic term encompassing many kinds of head pain with many potential causes. Tension-type headache is much more common than the other types of headache and occurs in the general population about fourfold more commonly than migraine (1).

For years, it was perceived that the headache of the fibromyalgia syndrome [FMS] was a tension-type [muscle contraction] headache involving the muscles of the neck, particularly the trapezius muscles which merge with ligaments that attach to the occiput. The traction on these ligaments was important to muscle contraction headache because the occipital nerves exit through foraminae in the back of the skull and penetrate the taut ligaments before fanning out anteriorly in the scalp. The belief was that these nerves were sufficiently compromised by the chronic tension on the ligaments to cause pain in the scalp. The pain is felt like a band around the head, with pressure behind both eyes, and aching in the area of the occiput where exquisite tenderness to palpation can be found and where a unilateral local injection of an anesthetic agent can attenuate or eliminate the local tenderness on the side of the injection.

More recently, headache nomenclature was changed and the FMS headache fell in the category of chronic daily headache because its frequency was often in excess of 15 days per month for the prior six months. This new classification helped to clarify the frequency of the FMS headache, but did not change the underlying pathogenesis, identify any other cause, or result in better management.

Many clinicians have diagnosed migraine in FMS headache sufferers, principally because of the severity of the symptoms. Those symptoms can include nausea but seldom progress to emesis. The problem with equating these dramatic clinical features with migraine is that people with FMS are unusually sensitive to many kinds of stimuli, including palpation pressure, bright light, and loud sounds even when they do not have headache. The FMS is an amplifier of neurological signals, so that these stimuli, which would not really bother a healthy normal control [HNC], are noxious to a person with FMS, and more so when they have an FMS headache. This could be interpreted as another manifestation of allodynia. Features of the FMS headache that help to distinguish it from migraine are the lack of a prodromal aura, lack of vision loss, lack of unilaterality, and lack of speech or language dysfunction in a postdrome. A potentially untoward consequence of identifying the FMS headache as migraine is that the typical response of a health care provider to migraine is to prescribe a serotoninergic [triptan] medication. That class of medication might be helpful for a migraine headache, but it might also induce the hyperserotonin syndrome in patients made more susceptible by concomitant therapy with a reuptake inhibitor drug such as a selective serotonin reuptake inhibitor or more likely a serotonin norepinephrine reuptake inhibitor or norepinephrine serotonin reuptake inhibitor medication, which are approved by the Food and Drug Administration for the treatment of FMS.

If clinicians must seriously consider the FMS headache diagnostically and therapeutically, what factors should enter into their deliberations? It is clear that many forms of headache in adults can be induced by insomnia, uncontrolled hypertension, a variety of medications taken for other conditions, dietary central nervous system [CNS] stimulants, presbyopia, giant cell arteritis, the myofascial pain syndrome [MPS], a variant of the MPS involving the muscles of mastication in the myofascial pain dysfunction syndrome also called the temporomandibular pain syndrome, or allergy/infection-induced sinusitis. In a given FMS patient, any combination of these contributing factors could be present. Depending on the differential and manual medicine skills of the primary care physician, it may be important to involve a variety of specialties in diagnosing and treating a patient with persistent, intractable FMS headache. The consultant list might include sleep physiology; neurology; physical medicine; ophthalmology; ear, nose, and throat; rheumatology; and dentistry.

Over 90 percent of FMS patients sleep so poorly that they are chronically sleep deprived. The FMS headache will often be due to insomnia and its consequences. Polysomnography in a newly diagnosed FMS patient is well justified to facilitate a physiological diagnosis of the insomnia's cause. Health-care professionals should advise patients on how to improve their sleep hygiene. That may require taking the television out of the bedroom, using a red nightlight to avoid interfering with melatonin production, and arrangements for an alternative sleeping environment when the patient awakens to a partner's loud snoring. Shift work is very poorly tolerated by people with FMS, so the physician may need to assist the patient in changing a work schedule which is impossible for him/her to maintain.

Because of the chronic insomnia, it is very common for FMS patients to abuse coffee, tea, cola drinks, or other stimulants to help them feel alert during the day. Use of a morning or daytime stimulant can produce a vicious cycle because the stimulant that is taken to start the day will further interfere with the subsequent night's rest. Typically there is a perceived need for progressive dosage escalation of the stimulant over time. Failure to escalate the dosage, or even any relative decrease in the average daily dosage, can precipitate a caffeine withdrawal headache.

A logical, but often strategically difficult solution to daytime tiredness, is to take a short nap when tired, rather than a stimulant, and then to ultimately discontinue use of the CNS stimulants. The non-steroidal drug, naproxen at 500 mg twice daily for two to three days, will attenuate the head pain of the caffeine withdrawal headache, but will not eliminate the subsequent desire to resume its use. As with tobacco habituation, there is a kind of comfort associated with sipping a flavored coffee while reading, or while visiting with a friend. Those habits will gradually lose their pull if the patient is convinced that the effort is worthwhile.

In addition to the potential health risks of the CNS stimulants in many consumed beverages, one must also be aware of the massive dosages of free sugars and dairy creams that accompany the stimulant. The logical alternative chosen by many patients is one of the artificial sweeteners which are used in the popular diet sodas. Several recent studies have evaluated the effects of drinking diet colas on body weight (2–5) but their findings vary, or are contradictory. A 2010 meeting of the British Nutritional Foundation explored the available data and concluded, “Overall the evidence suggests that [despite partial caloric compensation] beverages sweetened with intense sweeteners can contribute to weight control” (6). Of course, plain water would be at least as safe for people with FMS as the artificially sweetened beverages and would not contain the objectionable CNS stimulants.

The first research article in this issue of the Journal of Musculoskeletal Pain [JMP] comes from Madrid, Spain (7). The authors conducted an epidemiological evaluation of a large segment of the Spanish population to characterize what they define as disabling migraine headache. The database they used was the 2006 Spanish National Health Survey which contained the following three questions specifically related to migraine headache, as diagnosed by the patients' own neurologist. “Have you suffered from migraine headaches over the previous 12 months?,” “Has your neurologist confirmed the diagnosis of migraine?,” and “Have you had to reduce your main working activity or recreational activities in your free time for at least half a day during the last two weeks as a consequence of migraine?” The authors used positive responses to all three of these questions to populate their “affected” subgroup, while an unaffected subgroup was defined by negative responses to all three questions. Affected individuals were designated as having disabling migraine by virtue of their affirmative response to the second question. Two unaffected persons were demographically matched to each affected person for comparison analysis. The survey population included 29,478 Spanish subjects aged 16 years and older, from which 654 answered affirmatively to all three questions about migraine headache. The critical point to understanding why the prevalence of migraine identified in this study is lower than reported for other studies of migraine prevalence is that this unique subpopulation is composed of people with such severe migraine that they are disabled by its symptoms. The authors proceeded to characterize their subjects with disabling migraine by comparisons with the non-migraine controls. They sought evidence for psychological distress, duration of sleep, and a variety of other comorbid chronic conditions. The reader is directed to the authors' paper for more information regarding their findings and how the authors explain them.

The second research contribution comes from Istanbul, Turkey (8). In this communication, the authors referenced the theory that lateral epicondylitis might result from impaired blood flow to the soft tissues in the region of the pain/tenderness. They hypothesized that improvement of blood flow would directly address the pathogenesis and improve the symptoms. Their study was conducted by a randomized, double-blind, active comparator design with a sample size which was not large, but adequate to achieve statistical significance between treatment groups. For many years, the therapy of lateral epicondylitis had been without clear direction. If the findings of the current authors can be reproduced, it may be possible to really help the large number of persons with this condition. An extrapolation of this issue may be that people with FMS have lateral epicondylitis-like symptoms and examination findings. One could wonder whether patients with FMS lateral epicondylar pain/tenderness might be helped using this form of intervention.

The third research contribution comes from Zurich and Loèche-les-Bains, Switzerland (9). The authors studied the assessment of patients with complex regional pain syndrome type 1 [commonly designated CRPS 1] involving the upper extremities. Over half of the patients attributed their symptoms to a surgical intervention for another indication. The authors used two simple visual analog scales, one for pain and another for physical dysfunction as the primary outcome measures. The responses of their patients to the visual analog scale measures were compared with outcomes on more traditional measures. This work is important because the issue of valid status assessment is critical to the monitoring of responses to therapy for this condition. Since the authors studied quite a substantial number of patients with CRPS, their results are probably generalizable.

In the category of “True, true, but what does it mean?,” comes an interesting study by investigators from Mersin, Turkey (11). These investigators evaluated 15 women with FMS compared with 15 demographically matched HNC women. They carefully measured oxygen expenditures of the two groups at rest and again when they were walking at their preferred walking speed. The reader is encouraged to read the entire paper and ponder the author's conclusions. If their conclusions are to guide thinking on this topic, what would the most relevant intervention be?

The sixth full article is an interesting review of a didactic model of physiotherapy intervention from Ghent and Brussels, Belgium (11). The author's proposal makes use of the vertical physiotherapy intervention concept supported by the International Classification of Functioning, Disability and Health, but expands it to accommodate the relatively new information that has come with developments in the areas of pain mechanisms and biopsychosocial theory. The interactions of these later components with the more traditional vertical model results in a more planetary working model for conceptualizing physiotherapy and presenting it didactically. The reader is referred to the author's text to see how this proposed planetary model compares with the reader's own conceptual model and what the authors mean when they refer to red and yellow flags.

There is an interesting case report (12) from Gwangju, Donggu, Korea. The author describes successful management of a patient with Bertolotti's syndrome. This syndrome involves low back pain which is attributed to lower lumbar “kissing” lateral spinous processes. The contact between these lateral processes can be prompted by scoliosis or even by substantial loss of height in the intervertebral disc. The author treated one patient, at first conservatively with local anesthetic, and later more invasively with radiofrequency ablation at that site. The patient's pain was relieved. Details are provided by the article.

Please note the special interest columns which provide reviews of papers in other medical journals since the previous issue of the JMP. The topics of these reviews are FMS, MPS, and other soft tissue pain syndromes.

As always, readers of the JMP are invited to submit original manuscripts for blinded peer review, case reports of general interest, research ideas to promote further investigation, and letters to keep us all informed. The JMP editorial office frequently receives relevant books to be evaluated by and for the benefit of our readers. Book reviewers are allowed to keep the featured book after the evaluation report is completed. If you would be interested in being a book reviewer for the JMP, please communicate that to the editor.

Potential authors of contributions to the JMP should note that submissions and all communications between the authors and the JMP staff are to be accomplished online. Visit http://mc.manuscriptcentral. com/wjmp.

The clear mandate of the IMS, for which the JMP is the official journal, is to perpetuate the international meeting that is currently held every three years, but moving soon to an every two years schedule. The next international meeting will be MYOPAIN 2013 and will be held in Seattle, Washington, United States. The IMS website www.myopain.com will offer details as they become available.

It appears that the first Regional IMS Chapter will be organized this year in Thailand. Congratulations to them. Perhaps one of the organizers will provide JMP readers with a Letter to the Editor describing the proceedings.