as the link between pain and posture has been clearly demonstrated to patients, and they have been adequately educated, most are well able to treat themselves.
POSTURAL SYNDROME
In avoiding end-range postures in the cervical spine, the inter connectedness of lumbar and cervical postures must be made apparent to patients. The avoidance of sustained protruded head or neck flexion postures necessitates maintenance of the lumbar lordosis. Without correcting the lumbar posture, correction of the cervical posture will not occur.
When management by education is completed successfully, it should be explained to the patient that, although the present pain has been relieved, recurrence of similar symptoms is possible if postural care is neglected for extended periods. The consequences of postural neglect should be discussed.
Consequences of postural neglect
The effects of postural habits have long-term implications on the human shape (McKenzie 1981, 1990). The commonly observed posture of protruded head, rounded shoulders and flattened spine may become habituaL As age advances, permanent postural 'set' may occur - head protruded, shoulders rounded, dowager's hump, loss of lumbar lordosis and the erect posture replaced by a slight stoop. This is likely to be accompanied by considerable soft tissue adaptations. Positions that are frequently adopted, such as flexion, will be maintained, whilst movements that are rarely performed, such as extension, become steadily more difficult to achieve. Long term postural neglect can lead to adaptive tissue shortening, causing dysfunction syndrome.
As men and women age, their natural head position tends to progress to a more forward position; their ability to retract the head declines, whilst protrusion range is maintained, and there is an overall decline in antero-posterior mobility (Dalton and Coutts 1994). Between young adulthood and older age there is a reduction in all planes of cervical movements of 20 -45% (Worth 1994), and a reduction in
all planes of lumbar movements of about 30% (Twomey and Taylor 1994). In a meta-analysis of normative cervical motion, multiple studies demonstrated a decrease in cervical range with age (Chen et al. 1999) Although a large part of this may be the natural effects of ageing, there is also an element of variability in the degree to which people become restricted in range of movement and in resting postures. The mean range of movement decreases decade by decade,
400
1
CHAPTEIt TWENTY-THItEE THE CmVICAL & THOAACIC SPINE: MECHANICAL DIAGNOSIS & THEItAPYbut the standard deviation gets proportionally bigger as people age (Youdas
et al.
1992). This indicates considerable individual variability amongst an overall decrease in range.This means that protruded head positions and stooped postures are not simply an inevitable consequence of ageing. Movement that is lost because of tissue adaptation could have been retained had affected soft tissues been regularly stretched. If end-range movement is neglected, eventually that movement is lost forever. Postural 'sets' that arise from long-term postural neglect and tissue adaptation result from postural habit as much as the consequence o[ age. Loss of [unction can be prevented if end-range movements are regularly performed and posture corrected throughout life.
Thus, initially, poor postural habits produce pain of postural origin without loss of function. Prolonged postural neglect leads to adaptive shortening. If flexion is regularly performed but extension rarely, the anterior structures of the joints shorten and the posterior structures lengthen. Extension becomes more and more difficult to perform. Adaptive shortening implies loss of [unction and movement. When ever shortened structures are placed on stretch, they will induce discomfort or pain. Furthermore, the decreased movement must inevitably lead to impairment of nutrition in the intervertebral disc, contributing to disc degeneration.
The shortening of soft tissue, caused
by poor postural habit and inadequate exercise, can be prevented by
regular postural correction and adequate performance of the relevant
exercises
(McKenzie 1981, 1990). Furthermore, habitual poor posturepredisposes to derangement.
Conclusions
Only the patient can rectify pain of postural origin. No externally given treatment can alter the aggravating factor, which is their postural habit. To dispense treatment for a condition that can only be resolved through patient education is negligent health care. The essence of management for this condition is education and postural correction.
24: Headache
Introduction
Headache is a commonly reported symptom with a variety of causes, both serious and benign. Some headaches arise secondary to a neck problem with the primary complaint in the neck - such patients should be classified with one of the mechanical syndromes and managed in the same way as described elsewhere in the book. Some patients attend primarily with the complaint of headache, although there may be some secondary neckache - this chapter addresses this group. Headache means pain anywhere in the area of the occipital, parietal, temporal or frontal regions, and may also include symptoms around the eyes. Some of these patients have headaches that arise from upper cervical joints, and some will respond to mechanical therapy. There is a range of other causes of headache and some of these and the classification of headache are considered.
The task of a mechanical assessment, as in other areas of the spine, is first to determine those who are inappropriate for treatment and, with accompanying 'red flag' features, should be referred for further investigation. This differential diagnosis is performed principally on features from the history. Second, headache patients need to perform a mechanical evaluation as described below - some will demonstrate a beneficial or recognisable symptomatic response, and this group will benefit from mechanical therapy. Lastly, there will be a group who demonstrate no consistent mechanical response, whose symptoms are from some non-mechanical source.
Sections in this chapter are as follows: • epidemiology of headache
• causes of headache
differential diagnosis cervicogenic headache
• neuroanatomy of cervicogenic headache and experimental evidence
mechanical diagnosis and therapy and headaches
402
[
CHAI'TE� TWENTY-FOU� THE CE�VICAL & THOMCIC SPINE: MECHANICAL DIAGNOSIS & THEMPY • • • classification • derangement • dysfunction syndrome postural syndrome history physical examination mechanical assessment• retraction - sitting (Procedure 1)
• other tests
• management of mechanical cervical headache • correction of the lying posture
• modification of the lying posture.
Epidemiology of headache
Headaches are extremely common in the general population and a very common reason for seeking health care. The literature on the prevalence of headache in forty-four studies was summarised in 1999 (Scher et al. 1999). At age 40 there was an estimated prevalence in
males of 25% in Europe and just over 60% in North America, and in females of 70 - 80% in both these areas (Scher et al. 1999). It is
unclear why there is such a marked difference between European and North American males. Lifetime prevalence may be higher, with recent population studies giving figures of 83 - 93% of respondents reporting headache ever (Boardman et al. 2003; Ho and Ong 2003).
These studies make clear that headache is extremely common. About 2 - 4% of the general population report chronic daily headache, which may have persisted for years (Hagen et al. 2000; Lanteri.-Minet et al. 2003).
Complaints of headache have constituted 1.5 - 7% of patients visiting primary care physicians in North America (Becker et al. 1987; Hasse et al. 2002) and 4% in a UK general practice (Phizacklea and Wilkins
1978). A range of diagnoses was given: most commonly tension headaches, vascular, migraine, sinusitis and upper respiratory tract infection (Becker et al. 1987; Phizacklea and Wilkins 1978).
H EADACH E
Causes of headache
There are multiple listed causes of headaches (see Table 24.1). The most comprehensive attempt to classify headaches was made by the International Headache Society (IHS 1988), updated by a second edition in 2004. This listed thirteen separate groups, such as headaches associated with vascular disorders, substances or their withdrawal, non-cephalic infection, metabolic disorder, cranial neuralgias and so on (IHS 1988). More unusual causes are associated with serious pathology and systemic conditions and are obviously not appropriate for management by physical therapy. The more common causes are migraine, tension-type headaches and cervicogenic headache, which, although not always listed in differential diagnosis, have come to be accepted by the IHS. Other headache types include chronic parox ysmal hemicrania, cluster headaches and hemicrania continua. Some are simply Latinate descriptions of symptom features; for instance, the latter describes a continuous unilateral headache.
Table 24.1 Differential diagnosis of headache Type of lesiol1 Diagnosis
Intracranial Brain tumour
Mel1il1geal irritatiol1
Cral1ial
Vascular distu rbal1ces
Toxic states Extracral1ial Psychogen ic Brain abscess Subdural haematoma Acute meningitis Chronic meningitis Syphilis Tuberculosis Cryptococcosis Sarcoi.d Cancer Metasti.c neoplasms Paget's disease Migraine
Temporal arteritis (associated with polymyalgia rheumatica)
Sub-arachnoid haemorrhage Hypertension
Carotid/vertebral artery dissection Infections/alcoholism/lead/arsenic Lesions of eye
Lesions of middle ear Lesions of nasal sinuses
Lesions of oral cavity
Conversion hysteria/anxiety states Muscle tension
Continued next page
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1
CHAPTEIt TWENTY-FOUIt THE CEItVICAL & THOMCIC SPINE: MECHANICAL DIAGNOSIS & THERAPY Type of lesion Other Diagnosis Cervicogenic ClusterPost -trau matic Exertional Post -coital.
Source: Berkow et al. 1992; Mainardi et al. 2002; D'Andrea et al. 2002
It is hoped that any patients with headaches associated with serious pathology have been recognised and do not seek treatment from a musculoskeletal specialist. However, as this may not be the case and as musculoskeletal specialists can be front-line clinicians, an aware ness of 'red flags' as relevant to headaches is very important. These are suspected 'red flags' and their diagnostic acumen has not been formally tested. Severe headache has been the initial and salient symptom in a number of case studies in which the patient was finally diagnosed with acute myocardial infarction, carotid artery dissection, intracranial tumour, lung carcinoma or hypertension (Famularo et al.
2002; Mainardi et al. 2002; Pfund et al. 1999; Abraham et al. 2003;
Spierings 2002; Vazquez-Barquero et a1.l 994).
Table 24.2 Possible 'red flag' indicators of serious pathology
in headaches
progressive worsening of headache recent severe onset/thunderclap' headache onset of headache after exertion
onset of headaches> 50 years old history of major trauma
nausea/vomiting
temporal/occipital headache, with visual changes preceding sore throat/respiratory infection history of cancer
problems with speech/swallowing
visual changes - diplopia, ptosis, blurring
associated symptoms - progressive weakness, convulsions, blackouts,
mental changes, systemically unwell.
Source: Berkow et al. 1992; Pfund et al. 1999; Oh eL al. 2001; Makofsky 1994
Prevalence rates for the different types of headaches vary, but problems with classification mean that the true prevalence rates may only be estimates. In eighteen studies on the prevalence of migraine, using the International Headache Society's (IHS) diagnostic criteria, the
H EADACH E
estimated prevalence at age 40 in the general population was 6 - 7% in males and 15 - 22% in females in the Americas and Europe (Scher et al.
1999). Population studies since then have estimated similar levels: 6 -9% in men and 11 - 17% in women (Hagen et al. 2000; Dahlof and Linde 2001; Lampl et al. 2003; Ho and Ong 2003). Prevalence
increases up to age 40 and then declines.
In a population sample of 826 individuals, using limited IHS criteria, 2.5% of the general population and 18% of the frequent headache population were deemed to have cervicogenic headache (Nilsson 1995). Several studies have suggested the same range of cervicogenic headaches, around 15 - 20% of all headaches (Haldeman and Dagenais 2001). The mean age is 43, 79% are female, and mean duration of symptoms is 6.8 years (Haldeman and Dagenais 2001).
Tension headache is considered by some the most common type of headache with a one-month prevalence in the general population for mild and episodiC symptoms of between 20% and 50% (Rasmussen et al. 1991; Rasmussen 2001; Ho and Ong 2003). The prevalence of chronic, daily tension-type headaches in the general population is about 2 - 3% (Bahra and Goadsby 2000; Rasmussen 2001, Ho and Ong 2003). Prevalence is higher in women. As with other types of headache, prevalence declines with age, and a family history is common. Late onset headaches are generally unusual and may indicate serious pathology
Cluster headache is rare, with estimated prevalence between 0.07% and 0.4%, and unlike other headaches is more common in men (Dodick et al. 2000). Hemicrania continua is also considered to be
uncommon (Bigal et al. 2002a). Exertional headaches are thought to
be rare, but one study found a prevalence rate of 12 % (Sjaastad and Bakketeig 2002).
Several studies have investigated the proportion of different types of headaches in several hundred consecutive patients seeking treatment (Gallai et al. 2002; Mongini et al. 2003; CaSSidy et al. 2003; Fishbain et al. 2001). Migraine without aura is usually the most common
(57 - 70%), with fewer diagnosed with migraine with aura (6 - 55%), episodic or chronic tension-type headache (14 - 34%), cluster headache (3 - 5%) and cervicogenic headache (34%). However, these prevalence figures should probably be taken as estimates, and most of these groups did not include cervicogenic headaches. Due
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CHAPTER TWENTY-FOUR THE CERVICAL & THORACIC SPINE: MECHANICAL DIAGNOSIS & THERAPYto problems with classification, considerable variability in diagnosis has been found at different sites (Beghi et al. 2003).
Table 24.3 Diagnostic criteria for migraine without aura and
episodic tension headache
Migraine without aura Episodic tension headache
l. At least 5 headaches fulfilling l. At least 10 headaches fulfilling
points 2-4 points 2-4
2. Headaches last 4-72 hours 2. Headaches last 30 minutes to 7 days
3. Headache has at least two of 3. Headache has at least two of
follOwing: follOwing:
a. unilateral a. pressure/tightening
b. pulsating b. mild to moderate
c. moderate to severe c. bilateral
d. aggravated by routine d. no aggravation by routine
activity activity
4. Headache accompanied by at 4. With headache both of the
least one: following:
a. nausea/vomiting a no nausea/vomiting
b. photophobia and b. no photophobia and phonophobia phonophobia or only one,
not the other
5. Other headaches excluded. 5. Other headaches excluded.
Source: International Headache Society (IHS 1988)
Differential diagnosis
The prevalence figures suggest that the differentiation between the different headache types is straightforward, uncontroversial and simple to make, but this is not the case. One problem is the use of different diagnostic criteria. For instance, Haldemann and Dagenais (200 1) list five different criteria for cervicogenic headache, which have certain consistent features, but each includes distinctive characteristics. The most extensive classification criteria produced by IHS has been criticised on several counts (O'Driscoll 1999). It has had limited publication in a specialist journal, and therefore is not easily available; it is lengthy and very detailed for normal clinical practice. The groupings within the classification are based on structures and pathophysiological processes, whereas this is a particularly complex area that is relatively poorly understood in chronic benign headaches. The classification criteria are inconsistent, with some based on structure and others based on systemic disorders and still others on external factors, which might give rise to overlap (O'Driscoll 1999)
H EADACHE
Furthermore, due to the lack of empirical findings a large part of the work was based on expert opinion and consensus, and thus has been subject to a number of challenges (Gobel 2001). The authors, however, do acknowledge its limitations and state that it was primarily intended for research rather than clinical purposes (IHS 1988).
Other issues have highlighted the potential for confusion over classification (Chou and Lenrow 2002). There are several overlapping features between cervicogenic headaches, migraine and tension-type headaches, and it is recognised that reliable differential diagnosis in clinical practice is still a problem (Leone et al. 1998) Incorrect
application of the IHS criteria has been reported, with clinicians failing to gather full data, failing to make a specific diagnosis, or giving very different proportions of headache types when they do (Gallai et al.
2002; Blumenthal et al. 2003; Beghi et al. 2003). There are several
reports of overlap, with more than one set of diagnostic criteria being met by the same patient, and migraine, tension-type, cervicogenic or other headache type being reported in the same patient (Bono et
al. 1998, 2000; Antony 2000; Pfaffenrath and Kaube 1990; Sjaastad and Bovim 1991; Bigal et al. 2002b; Sanin et al. 1994; Fishbain et al.
2001). Even apparently distinct features for cervicogenic headache, such as onset with neck position, movement or trauma and other neck-associated symptoms are frequently found in other types of headaches (Fishbain et al. 2001). This suggests these are not discrete
categories that are distinct from each other. Although significant differences in diagnostic features have been reported between cervi cogenic headache, migraine and tension-type headache, few features are reported solely in one type of headache (Vincent and Luna 1999). Using a constellation of features is diagnostically more accurate than relying on single features.
Critics have come up with a range of reasons why the IHS classification system may be unstable. This may be because of overlapping symptoms, fluctuating patterns of symptomatology, the obscuring effect of self medication, the possibility that different headache types are not in fact distinct disorders but share a common pathophysiological basis, and the limited validity and reliability of the classification criteria (Beghi et al. 2003).
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CHAPTER TWENTY-FOUR THE CERVICAL & THORACIC SPINE: MECHANICAL DIAGNOSIS & THERAPYCervicogenic headache
The first description of cervicogenic headache was in 1983 (Sjaastad et al. 1983), and the lHS classification was amended in 1988 to include headaches related to neck problems. Since then several groups have published diagnostic criteria or amended earlier ones (Sjaastad et al. 1990, 1998; Merskey and Bogduk 1994; Meloche et al. 1993; Jull 2002). Although these contain certain common features, they also contain many inconsistencies. Differences include the location of pain, whether it is unilateral or bilateral, and whether it can change sides or not. Some include a positive response to nerve blocks, one included radiographic criteria, some stipulated neck trauma, one focussed on abnormalities in local muscles and one included additional symptoms. Most agree that pain starts around the occipital area and can be aggravated by neck movement. Some state aggravation by posture as well, most note a decrease in cervical range of movement and most include neck tenderness to palpation or reproduction of headache on palpation. It does not appear that any specific tests or clinical finding has been determined to be pathognomonic of cervicogenic headache (Haldeman and Dagenais 2001). Features that most clearly distinguished cervicogenic headache from other headache types were: unilateral, side-locked headache with neck pain and headache associated with neck movements or postures (Vincent and Luna 1999; Bono et al. 1998)
There was initially reluctance by some headache speCialists to accept the concept of cervicogenic headaches (Bogduk 2001). As with other headache classifications, there are problems with recognition. The validity of the diagnostic criteria to delineate a unique entity has been challenged, as there is considerable overlap with migraine and tension-type headache (Leone et al. 1998; Antonaci et al. 2001). The overall reliability of making a diagnosis of cervicogenic headache from history and physical examination is moderate, kappa 0.51 (van Suijlekom et al. 1999). Items from the history had kappa values between 0.08 and 0.76. In the physical examination pain provocation movements were more reliable (kappa 0.53 - 050) than range of movement tests (kappa 0.32 - 0.41), with provocation of headaches by manual pressure on the zygapophyseal joints the least reliable (kappa 0.16 - 0.23). Overall, agreement on the existence of cervicogenic headache amounted to 76%, similar to migraine (77%), with tension-type headaches being the least reliably detected (45%) (van Suijlekom et al. 1999).
H EADACHE
In a reliability study to detect painful upper cervical joint dysfunction by manual examination in forty subjects with and without headaches, overall agreement was generally excellent, with kappa values mostly 1.00 Gull et al. 1997). However, of twenty volunteers without symptoms,
three were judged to have upper cervical joint dysfunction. It is claimed that manual examination can differentiate different headache types, but the claim is based on unpublished data, and a caveat is made that tenderness over cervical joints is present in all headache types and in those with no headache Gull and Niere 2004). In another reliability study in which the examiners used both active and passive