An Investigation of Cervical Spinal Posture in Cervicogenic Headache Peter K. Farmer, Suzanne J. Snodgrass, Anthony Buxton and Darren A. Rivett PHYS THER. Published online October 9, 2014 doi: 10.2522/ptj.20140073
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1 Running head: Cervical Spine Posture in Cervicogenic Headache
Research Report
An Investigation of Cervical Spinal Posture in Cervicogenic Headache
Peter K. Farmer, Suzanne J. Snodgrass, Anthony Buxton, Darren A. Rivett
P.K. Farmer, BAppSc(Physio), MMedSc(Physio), Thrive Physiotherapy, Erina, New South Wales, Australia.
S.J. Snodgrass, PT, PhD, MMedSc(Physio), Discipline of Physiotherapy, School of Health Sciences, Faculty of Health and Medicine, Hunter Building, University of Newcastle, University Drive, Callaghan, New South Wales 2308, Australia. Address all correspondence to Dr Snodgrass at: [email protected].
A. Buxton, DipAppSc(Med Rad), MHEd, Discipline of Medical Radiation Science (Diagnostic Radiography), School of Health Sciences, Faculty of Health and Medicine, The University of Newcastle.
D.A. Rivett, PhD, MAppSc(ManipPhty), BAppSc(Phty), Discipline of Physiotherapy, School of Health Sciences, Faculty of Health and Medicine, The University of Newcastle.
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2 [Farmer PK, Snodgrass SJ, Buxton A, Rivett DA. An investigation of cervical spinal posture in cervicogenic headache. Phys Ther. 2015;95:xxx–xxx.]
© 2014 American Physical Therapy Association
Published Ahead of Print: xxx Accepted: October 2, 2014 Submitted: February 24, 2014
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3 ABSTRACT Background. Cervicogenic headache (CGH) is defined as headache symptoms originating from the cervical spine. Cervical dysfunction from abnormal posture has been proposed to aggravate or cause CGH, but there are conflicting reports as to whether there is an association between posture and CGH. Objective. To evaluate differences in cervical spinal posture, measured on radiographs, between patients with probable CGH and asymptomatic control participants. Design. Single blinded comparative measurement design. Methods. Differences in postural variables from radiographs between CGH (n=30) and aged and gender matched asymptomatic control participants (n=30) were determined using paired t-tests or the non-parametric equivalent. Postural variables were general cervical lordosis (GCL, Cobb angle C2-C7), upper cervical lordosis (UCL, sagittal alignment C2 compared with C3-C4) and C2 spinous process horizontal deviation. Logistic regression determined postural variables increasing the likelihood of CGH. Results. There were no significant differences in posture between CGH and controls (mean GCL, CGH group 10.97°, SD 7.50, controls 7.17, SD 5.69, P = 0.06; UCL CGH 11.86°, SD 6.46, controls 9.44, SD 4.28, P = 0.10; C2 spinous process horizontal deviation CGH 3.00mm, SD 1.66, controls 2.86, SD 2.04, P = 0.77). However, there was a significant association between greater GCL and an increased likelihood of having CGH (OR=1.08, 95% CI 1.001, 1.191, P=0.042). Limitations. The findings are limited to an association between GCL and posture, as cause and effect cannot be determined.
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4 Conclusion. The association between greater GCL and increased likelihood of having CGH suggests that GCL might be considered in the management of patients with CGH. However, as the data do not support posture as a cause of CGH, it is unknown whether addressing posture would reduce CGH.
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5
INTRODUCTION Assessment and treatment of posture is common despite there being very little evidence that altered posture is associated with symptoms, or that treatment strategies can improve posture related symptoms.1, 2 The assessment of posture assumes that identifying postures that are different to the ‘ideal’ posture may provide a meaningful clinical sign that may be related to dysfunction and/or symptoms.3 If abnormal posture is not related to dysfunction or symptoms, then the justification of clinical postural assessment is limited. Therefore, research to establish associations between postural variables and symptoms in patients is important for justifying current clinical practices. There are very few postural abnormalities that have been directly related to symptoms.2
Cervicogenic headache (CGH) is a type of secondary headache where the symptoms originate from a dysfunction in the cervical spine.4, 5 Cervical dysfunction from abnormal posture is one factor that has been proposed to aggravate or cause CGH.6, 7 The proposed association between abnormal cervical posture and headache has been demonstrated in migraine and tension type headaches8-10 but there are conflicting results in CGH.1, 11-13 Despite this lack of agreement, clinicians routinely assess and treat altered posture for CGH,1, 2 therefore it is important to examine possible associations in order to guide treatment.
The craniovertebral angle (between the horizontal line passing through C7 and a line extending from the tragus of the ear to the tip of the C7 spinous process10) as measured from photographs has been used to investigate associations between cervical posture and CGH with conflicting results. Two studies in adults reported no
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6 association11, 13 and one study in children aged six to twelve reported an association between a smaller craniovertebral angle (i.e., increased forward head posture) and the presence of CGH.14 This conflicting evidence suggests that craniovertebral angle measurements may not isolate the specific postural factors that may be associated with CGH symptoms.15 Therefore, to determine potential posture variations in patients with CGH, radiographic measurements are needed. Only one identified study used radiographs to assess static cervical lordosis posture in patients with headache and showed that decreased cervical lordosis was associated with tension headaches.16 Tension headache is considered a different headache type to CGH and therefore postural presentations may differ in CGH requiring investigation.
C2 is proposed as the most common cervical level for CGH genesis with both the C1/2 and C2/3 joints suggested as the dominant motion segment.15, 16 The C2/3 motion segment has been reported by some groups to be the most common source of CGH symptoms,5, 17, 18 with diagnostic blocks suggesting the third occipital nerve located at C2/3 was implicated as the pain source in approximately 53% of 15 patients with CGH.19 Alternatively, C1/2 was reliably palpated by two examiners as the symptomatic cervical level in 63% of 60 patients with CGH.20 Two investigations of ‘unilateral’21 and migraine22 headaches that assessed the position and symmetry of the C2 spinous process using imaging (computed tomography and radiography, respectively) have reported that altered C2 spinous process horizontal plane alignment is associated with headaches. However, due to the use of descriptive rather than standardised headache criteria, the participant samples potentially included a mix of headache types, so conclusions about the relationship of C2 spinous process horizontal alignment and CGH cannot be determined.
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7
This aim of this study was to determine if cervical spine posture is altered in patients with CGH as compared to age and gender matched asymptomatic individuals. This is a first step in determining whether posture is worth considering in larger studies that assess the possible contributing factors to CGH symptoms. Determining whether there is a relationship between CGH and cervical posture may potentially provide clinicians with evidence supporting the assessment and treatment of posture in this patient group.
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8 METHODS
A single blind, age and gender matched, comparative measurement design was used to evaluate the differences in cervical spinal posture, as measured on cervical radiographs, between asymptomatic participants (control group) and participants with CGH. Participants were recruited using flyers placed on noticeboards on the university campus where the study was conducted. Interested participants were first screened by telephone for inclusion. The study protocol was approved by the University’s Human Research Ethics Committee and all participants provided written informed consent. No funds were received in support of this work and the authors have no conflict of interest.
Participants Participants were healthy adults aged between 18 and 50 years with a primary complaint of headache and no history of significant medical conditions that might be potential contraindications to physical examination of the cervical spine, including known cancer, osteoporosis, nerve root symptoms, inflammatory or infectious diseases affecting the neck, instability of the cervical spine, or reported potential vertebrobasilar insufficiency symptoms.23 This age range was used so that altered upper neck posture associated with different age groups15 was not a confounding factor in the analysis of posture in the symptomatic and asymptomatic groups. Potential participants who were possibly pregnant were excluded as radiography was to be used in the study. Asymptomatic participants were age and gender matched with CGH participants. Participants with CGH diagnosis were included if their pattern of symptoms was consistent with the diagnostic criteria of the ‘Cervicogenic Headache International Study Group’ (CHISG, Table 1).24 These diagnostic criteria have been used widely as the basis for inclusion in
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9 CGH studies.13, 25, 26 The potential CGH participants were screened by telephone for a pattern of symptoms consistent with the CHISG diagnostic criteria. To be included participants had to have (1) a unilateral headache at least once per week over the previous 2 months (unilaterality consistent on one side, not a headache that swapped sides), (2) which was associated with neck pain before, during or following the headache and (3) aggravated by movement or specific postures of the neck). This description of neck pain is consistent with criteria Ia(1) of the CHISG criteria. Those who experienced an aura with their headache or who were involved in claiming workers’ or third party compensation or litigation were excluded. Those reporting the required pattern of headache symptoms progressed to a physical assessment to determine study eligibility as long as they had also not received any manual therapy treatment for the previous 2 months, as the potential effect of manual therapy on posture is unknown. The physical assessment consisted of an experienced physiotherapist (with professional qualifications in manual therapy and 16 years clinical experience) applying pressure over the spinous and articular processes of the cervical spine with the participant positioned in prone lying. The techniques used for this palpation assessment were common cervical spine posteroanterior passive accessory intervertebral movement assessment techniques.25 A potential participant with headache was eligible if they met the CHISG criterium for the reproduction of “head pain, similar to the usually occurring one” with palpation.24 The identification of patients with CGH thus required potential participants to meet criteria Ia, both (1) and (2), and criteria III of the CHISG criteria (Table 1). Participants may also have met criteria Ib and c, but potential participants were not excluded if they did not meet Ib and c (Table 1). As diagnostic blocks were not used (criteria II, Table 1), participants with CGH were considered to have “probable” CGH, based on the best available diagnostic criteria without the use of invasive techniques. Asymptomatic control participants also underwent the physical palpation assessment to maintain consistency between study groups, as
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10 the possible effects of this palpation assessment on posture are unknown. The therapist performing the physical assessment was blinded as to the headache status of the potential participant. Asymptomatic participants were eligible as long as they did not report any head pain with the physical assessment.
Radiographic Methods The study used radiographic measurements to quantify posture as these methods have been demonstrated to allow specific segmental measurements of cervical spine posture.15, 27 Two standard views of the cervical spine (one anterior-posterior (AP) open mouth view and one lateral view, both in standing) were taken to facilitate generalization to clinical practice. Radiographic examinations were performed by a registered radiographer with 35 years’ experience using standardized positioning techniques and participant instructions.28 The radiographic views and instructions were consistent with a standard cervical radiographic series as performed in clinical radiography practice. Participants were asked to stand in a normal comfortable posture with their arms relaxed, and to look straight ahead. The images were taken in suspended respiration during normal shallow breathing at rest, with the instruction to ‘stop breathing now.’ Participants were not given any instructions for the timing of inspiration or expiration, as forced voluntary breathing causes thoracic cavity movement and body sway, whereas normal involuntary breathing does not result in excessive movement or blurring of the image.28
Radiographs were performed using a Philips Diagnostic Vertical Bucky Stand attached to a Philips Optimus 50 Medium Frequency Generator and Philips R0 1648 Hi-Speed Rotating Anode X-Ray tube in a Philips ROT 360 X-ray Tube Housing (Philips Healthcare, Best, Holland). Two Fuji Computed Radiography (model DS) imaging cassettes were used comprising one 18x24 cm
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11 cassette (for AP open mouth view) and one 24x30cm cassette (for lateral view, Fujifilm Holdings Corporation, Tokyo, Japan). The cassettes contained a standard definition Fuji Digital Image Receptor Plate Model: CR ST-VI (Fujifilm Holdings Corporation, Tokyo, Japan). All images were obtained using a grid technique (105 line/inch 12:1 grid). The lateral view radiographic projection used a focal film distance of 178cm, and for the AP open mouth view 110cm.
Radiographic Measurements The radiographic images were obtained digitally and then transferred to Centricity Webpacs V2.1 (GE Medical Systems, Wisconsin, USA), a software system used to perform measurements. A qualified radiographer experienced in the use of this measurement tool performed all measurements using the same computer and monitor for each participant. A second experienced radiographer repeated the measurements on a subset of 20 randomly selected participants to determine inter-rater reliability of the on-screen measurement techniques. Both radiographers were blinded to the headache status of each participant and the measurements of the other radiographer. Good reliability has been previously demonstrated for these methods when they were performed by drawing on hard copies of radiographs,15, 29-31but is unknown for digitised images using the Centricity Webpacs software.
The posture measurements performed on the lateral radiographic view were general cervical lordosis (GCL) and upper cervical lordosis (UCL). The GCL measurement was based on the ‘Cobb method’.29 It was obtained by drawing lines parallel to the inferior end-plates of C2 and C7 and then the software package generates perpendicular lines to those drawn. The acute angle formed between these lines was calculated by the software package and recorded as GCL (Figure 1a). A higher value for GCL indicated a participant had greater cervical lordosis between C2 and
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12 C7. The UCL radiographic measurement, based on the technique described by Johnson,15 involved drawing a line between the most superior-posterior point on the odontoid process of C2 and the most inferior-posterior point on the body of the second cervical vertebra. A second line was then drawn connecting the most inferior-posterior point on the body of C3 with the most inferior-posterior point on the body of C4. The angle for UCL was determined by measuring the acute angle formed between these two lines (Figure 1b). A higher value for UCL indicated a participant had greater cervical lordosis between C2 and C4. The AP open mouth radiograph view was used to measure the position of the C2 spinous process relative to the midline (Figure 2). This involved a measurement of the distance that the C2 spinous process deviated from the mid-line at the level of the atlas.27 This was determined by drawing two vertical lines: one passing through the mid-point of the tip of the odontoid process and one through the mid-point of the spinous process of C2. The distance between these two lines in mm determined the C2 spinous process deviation, with greater values for increased deviation.
Data Analysis Sample size estimations suggested that potentially meaningful differences of 10° and 5° in GCL29 and UCL15 respectively between groups could be detected with 80% power with 22-24 participants per group. As the variability of C2 spinous process horizontal deviation was unknown, 30 participants per group were recruited. Intraclass correlation coefficients (ICC 2,1) and 95% confidence intervals (CI) determined the inter-tester reliability of the radiographic measurements. Data were checked for normality and non-parametric methods were used where appropriate. Differences in C2 spinous process horizontal deviation and UCL between the CGH group and control group were determined using t-tests. The difference in GCL between groups was determined using the Wilcoxon Rank Sum test.
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13
A matched pairs binary logistic regression determined whether measurements taken of cervical spinal posture on radiographs (GCL, UCL and C2 spinous process horizontal deviation) demonstrated an association with the likelihood of experiencing CGH. Analyses were completed using JMP 10 and SAS 9.2 (SAS Institute, Inc., Cary, NC, USA).
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14 RESULTS Approximately 300 potential participants were screened by telephone using the CHISG criteria (Figure 3). The most common reasons for exclusion were the presence of bilateral headache or an aura. Control participants were only recruited when a participant of the same gender and similar age had already been recruited in the CGH group, so exclusions occurred if matching was not possible. Thirty participants with probable CGH (mean age 31.4 years, SD 10.0 years, 26 females) and 30 age and gender matched controls (mean age 29.8 years, SD 9.4 years, 26 females) were recruited. Participants with CGH reported a mean frequency of 1.2 headaches per week (SD 1.8, range 1 to 7), and a mean duration of 152.4 weeks (SD 311.7, range 2 months to 30 years). All potential CGH group participants who met the telephone screening criteria reported reproduction of their familiar headache on palpation, and were included in the study. Digital radiographs were technically compromised for two participants, one from the CGH group and one from the control group; therefore radiographic data analyses are from 58 participants. The inter -tester reliability of the radiographic measurements was good to excellent: UCL (ICC 0.75, 95% CI .047,0.89), C2 spinous process horizontal deviation (ICC 0.88 95% CI 0.73,.0.95) and GCL (ICC 0.90, 95% CI 0.77, 0.96).
There were no significant differences between the control and CGH groups for the three radiographic postural measurements (Table 2). Logistic regression demonstrated that as the GCL increased there was a statistically significant increased likelihood of having CGH (P = 0.042). The odds ratio of 1.08 (95% CI 1.0 to 1.19) suggests that with each degree increase of GCL, there was an approximate 8% increased likelihood of having CGH in this sample. There were no associations between CGH and UCL or C2 spinous process deviation (Table 3).
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15 DISCUSSION This study is the first to investigate the association between posture and CGH using a radiographic analysis of the cervical spine. The results indicate that cervical spine posture, as defined by the radiographic methods in this study, cannot be used to differentiate between individuals with probable CGH and those who are asymptomatic. However, an increase in GCL was found to be associated with an increased likelihood of experiencing CGH, though UCL and C2 spinous process horizontal deviation were not associated with CGH. The significant variability in cervical spinal posture in the absence of symptoms has been reported to contribute to difficulties in distinguishing postural types between asymptomatic and symptomatic individuals.15, 32 This result is also consistent with a previous study in CGH that indicated that isolated clinical signs were not sufficient to differentiate those with CGH.33 Though the posture variables measured in this study did not differentiate individuals with CGH from those who were asymptomatic, the association between increased GCL and an increased likelihood of having CGH suggests that GCL may be worth considering in assessment of patients with CGH.
Interpreting the odds ratio for the association between GCL and CGH (1.08), each degree of increased lordosis increases the odds of having CGH by 8% (as compared to asymptomatic control participants in this study). However, the 95% CI for the odds ratio (1.0 to 1.19) suggests that there is either no association or the odds of having CGH may be as high as 19% per degree increase in GCL. As the confidence interval for the odds ratio suggests that there may not be an association, the routine assessment of GCL as an isolated clinical sign is not justified. The inability of any single clinical sign or injection procedure to discriminate CGH is consistent with the description of CGH as a syndrome34-36 characterized by a combination of movement, joint and muscle dysfunction.37, 38 However, a combination of clinical signs
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16 (restricted cervical movement, impairment in the craniocervical flexion test and palpable upper cervical joint dysfunction) has been demonstrated to reliably identify CGH.33 The results of the current study suggest that further investigation may be warranted to determine if increased GCL may improve the identification of CGH when considered in combination with other clinical signs.
Previous studies have demonstrated an association between decreased cervical lordosis and tension type headache14 or neck pain.39, 40 In contrast, the present study demonstrated an association between CGH and increased cervical lordosis. This is consistent with a previous study in children that found increased forward head posture as measured by craniovertebral angle (which might be expected to be associated with increased cervical lordosis) was associated with having CGH. These results together suggest that increased cervical lordosis may well be unique to CGH and could be associated with the upper cervical muscle dysfunction that is a feature of CGH.33, 41 One possible theory explaining the relationship between CGL and CGH may be related to muscle dysfunction,42 as upper cervical flexor muscle dysfunction has been established as a feature of CGH,33, 41 and treatments to improve muscle function and control have been demonstrated to be effective in patients with CGH.41, 43-45
However, the effects of improved muscle function on posture in patients with CGH are
unknown, as relationships between improved muscle function and posture have only been demonstrated in patients with neck pain46, 47 and not CGH.
The interpretation of the results of the present study should be made in the light of the results of previous studies investigating cervical lordosis. No previous studies were identified assessing general GCL in patients with CGH using the radiographic C2-C7 Cobb angle
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17 measurement, and few studies in patients with cervical dysfunction. C2-C7 Cobb angles have been reported for patients with neck pain39 and asymptomatic individuals.48 Using similar measurement methods to the current study, Harrison et al.39 found greater lordosis in those with neck pain compared to asymptomatic controls. Harrison et al.39 reported Cobb angles (mean 12.7°, SD 12.5°) in their ‘chronic pain’ group (neck pain symptoms > 12 weeks) that were comparable to the current study (mean 11.0°, SD 7.5°). Conversely, Matsumoto et al. found no difference in the prevalence of lordotic curvature versus non-lordotic curvature in patients with acute whiplash compared to asymptomatic controls, however, these findings were based on observation rather than measurements.49 The GCL values in asymptomatic participants in the current study (mean 7.1, SD 5.7) are consistent with C2-C7 Cobb angles reported by Park et al.48 for their asymptomatic ‘younger’ group (aged 20-29 years, mean 9.0, SD 11.0), but much lower than values reported for asymptomatic participants in the Harrison et al.39 study (mean 26.8, SD 9.7). Harrison et al.39 excluded participants with excessive head protrusion (perpendicular distance from C2 to C7 >25.4mm for their pain groups and >10 mm for their control group), partially explaining the differences. Harrison et al.39 also had a lower proportion of females (50%) compared to the current study (86%), and females have been shown to have greater cervical lordosis than males (demonstrated using different radiographic assessment methods).16, 50 These findings suggest that increased GCL may be a factor in both neck pain and headache, but further research is needed to confirm this.
The lack of statistically significant associations between the two investigated upper cervical spinal postural variables and CGH suggests that despite the upper cervical region being considered the predominant region for the generation of CGH,51-53 symptoms may not be associated with upper cervical postural variations. As increased UCL is one of the
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18 components of forward head posture, these results support the findings of previous investigations that concluded there is no association between forward head posture and CGH,11, 13but contrasts with the study by Budelmann et al.14 showing forward head posture was greater in children with CGH. The current study findings of no association between CGH and C2 spinous process horizontal deviation concurs with one previous study reporting that deviation of the C2 spinous process in headache patients may be coincidental.54 This potentially means that other impairments in the upper cervical region (e.g. muscular dysfunction) may instead be contributing to symptoms, rather than localised postural characteristics. Further, the association of GCL with CGH despite expectations that the UCL would be more likely involved is consistent with a previous case study that reported improvements in CGH following treatment to improve general posture.55 One hypothesis may be that altered general posture contributes to the likelihood of CGH due to the effects on larger muscle groups (e.g., levator scapulae) that attach to the upper cervical levels.
Limitations The participants in this study were recruited via advertisements rather than patients presenting at a clinic, which may bias the results. However strict selection criteria were used, based on the CHISG major criteria for CGH diagnosis.24 The CHISG recommends the use of diagnostic anaesthetic blockades to provide a definitive CGH diagnosis,24 which this study did not employ. Previous studies have also not used diagnostic anaesthetic blockades as they are considered invasive and associated with unjustifiable risk in the research setting with volunteer participants.13, 43 Moreover, diagnostic anaesthetic blockades abolish other types of headaches56 and therefore do not establish an unequivocal CGH diagnosis. They also rely on the participant presenting for assessment at the time they are experiencing symptoms. Participants were included in the current study if they regularly experienced CGH, rather than
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19 if they had a presenting headache, and the presence or absence of CGH symptoms at the time the radiograph was taken were not recorded. As CGH is typically an intermittent headache that does not occur in a predictable cycle and patients often present in the clinical setting during symptom-free periods, it was considered important to investigate posture irrespective of participants’ symptoms at the time of assessment. Furthermore, though the reproduction of a participant’s familiar headache was used as one assessment component to identify patients with CGH as recommended in the CHISG diagnostic criteria, it is acknowledged that pain on palpation of the cervical spine may also occur in patients with other types of headaches, suggesting this criterion is not specific to CGH.57 The reproduction of familiar headache by palpation was used in addition to the descriptors consistent with CGH as described in the CHISG criteria as an additional component supporting the likelihood of a participant’s headache being cervical in origin, as in a previous study.58 In terms of the possible confounders of the posture measurements, the radiographs in this study were not assessed for pathology so other possible contributors to the presenting postures cannot be determined. Furthermore, the palpation assessment may have also been a confounding factor, as the effect of palpation on posture is unknown. To minimise the potential for confounding, the palpation assessment was performed on all participants using the same method and in the same sequence regardless of the participant’s headache status. Lastly, as this study was a comparative study design, only an association between posture and CGH can be demonstrated, and it is unknown whether increased GCL posture causes CGH or having CGH leads to an increase in GCL. Additional factors that may contribute to symptoms, such as psychosocial variables, were not explored in this study, therefore the interpretation of the results is limited to the possible association of posture to symptoms.
Future Research
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20 Future investigations could aim to determine if the postural association identified in the current study is a causative factor for CGH or instead a response to symptoms, and if changing the GCL has an effect on symptoms. Additionally, a larger multifactorial study may investigate posture with other possible factors influencing the development of symptoms, such as psychosocial factors. Further research into cervical posture using radiographs in other headache types may help determine whether posture could be useful for diagnostic differentiation of headache types. Research may also focus on the potential relationships between upper cervical muscle dysfunction and posture, which might direct future treatment strategies in CGH.
Conclusion The present study found that three components of static cervical spinal posture commonly used clinically cannot be used to discriminate participants with CGH from asymptomatic individuals. However, increased GCL was associated with an increased likelihood of having CGH. Therefore, clinicians may consider GCL when assessing or treating patients with CGH. It should be noted that the results of this study suggest the degree of GCL cannot identify a patient with CGH so the routine assessment of GCL in all patients with CGH is not supported.
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21 Acknowledgments All authors provided concept/idea/research design, writing, and data collection. Mr Farmer, Dr Snodgrass, and Mr Buxton provided data analysis. Mr Farmer and Mr Rivett provided project management. Dr Snodgrass and Mr Buxton provided facilities/equipment. Dr Snodgrass, Mr Buxton, and Mr Rivett provided consultation (including review of the manuscript before submission). The authors acknowledge John Tessier for his assistance with data collection.
An abstract of the study was presented at the Musculoskeletal Physiotherapy Australia 16th Biennial Conference; October 1-5, 2009; Sydney, Australia.
DOI: 10.2522/ptj.20140073
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22
References 1.
Christensen ST, Hartvigsen J. Spinal curves and health: A systematic critical review of the epidemiological literature dealing with associations between sagittal spinal curves and health. J Manipulative Physiol Ther. 2008;31(9):690-714.
2.
Refshauge K, Gass E. Musculoskeletal Physiotherapy - Clinical science and evidencebased practice. 2nd ed. Oxford: Butterworth Heinemann; 2004.
3.
Troyanovich SJ, Harrison DE, Harrison DD. Structural rehabilitation of the spine and posture: rationale for treatment beyond the resolution of symptoms. J Manipulative Physiol Ther. 1998;21(1):37-50.
4.
Antonaci F, Sjaastad O. Cervicogenic headache: a real headache. Curr Neurol Neurosci Rep. 2011;11(2):149-55.
5.
Bogduk N, Govind J. Cervicogenic headache: an assessment of the evidence on clinical diagnosis, invasive tests, and treatment. Lancet Neurol. 2009 Oct;8(10):959-68.
6.
Richardson CJ. Treatment of cervicogenic headaches using Mulligan "SNAGS" and postural re-education: a case report. Orthopaedic Physical Therapy Practice. 2009;21(1):33-8.
7.
Jull G. Management of cervical headache. Man Ther. 1997;2(4):182-90.
8.
Fernandez-de-las-Penas C, Alonso-Blanco C, Cuadrado ML, Pareja JA. Forward head posture and neck mobility in chronic tension-type headache: a blinded, controlled study. Cephalalgia. 2005;26:314-9.
9.
Fernandez-de-Las-Penas C, Cuadrado ML, Pareja JA. Myofascial trigger points, neck mobility and forward head posture in unilateral migraine. Cephalalgia. 2006;26(9):106170.
Downloaded from http://ptjournal.apta.org/ by Barbara Shipman on October 16, 2014
23 10. Fernandez-de-Las-Penas C, Cuadrado ML, Pareja JA. Myofascial trigger points, neck mobility, and forward head posture in episodic tension-type headache. Headache. 2007;47(5):662-72. 11. Dumas JP, Arsenault AB, Boudreau G, Magnoux E, Lepage Y, Bellavance A, et al. Physical impairments in cervicogenic headache: traumatic vs. nontraumatic onset. Cephalalgia. 2001;21(9):884-93. 12. Watson DH, Trott PH. Cervical headache: an investigation of natural head posture and upper cervical flexor muscle performance. Cephalalgia. 1993;13:272-84. 13. Zito G, Jull G, Story I. Clinical tests of musculoskeletal dysfunction in the diagnosis of cervicogenic headache Man Ther. 2006;11(2):118-29. 14. Budelmann K, von Piekartz H, Hall T. Is there a difference in head posture and cervical spine movement in children with and without pediatric headache? Eur J Pediatr. 2013;172:1349-56. 15. Johnson GM. The correlation between surface measurement of head and neck posture and the anatomic position of the upper cervical vertebrae. Spine. 1998;23(8):921-7. 16. Nagasawa A, Sakakibara T, Takahashi A. Roentgenographic findings of the cervical spine in tension-type headache. Headache. 1993;33:90-5. 17. Cooper G, Bailey B, Bogduk N. Cervical Zygapophysial Joint Pain Maps. Pain Med. 2007;8(4):344-53. 18. Jull G. Manual diagnosis of C2/3 headache. Cephalalgia. 1985;5(3):308-9. 19. Lord SM, Barnsley L, Wallis BJ, Bogduk N. Third occipital nerve headache: a prevalence study. J Neurol Neurosurg Psychiatry. 1994;57(10):1187-90. 20. Hall T, Briffa K, Hopper D, Robinson K. Reliability of manual examination and frequency of symptomatic cervical motion segment dysfunction in cervicogenic headache. Man Ther. 2010;15:542-6.
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24 21. Boquet J, Moore N, Payennville G, Leclerc D, Montier F, Boismare F. Use of CT scans in the study of the upper cervical vertebrae in strictly lateralised migrainous headache (and other intermittent headache?) In: Rose FC, editor. New advances in headache research. London: Smith-Gordon and Company 1989. p. 45-8. 22. Boquet J, Biosmare F, Payenneville G, Leclerc D, Monnier J, Moore N. Lateralization of headache: Possible role of upper cervical trigger point. Cephalalgia. 1989;9:15-24. 23. Murtagh JE, Kenna CJ. Back Pain & Spinal Manipulation. 2nd ed. Oxford: Butterworth Heinemann; 2001. 24. Sjaastad O, Fredriksen TA, Pfaffenrath V. Cervicogenic headache: Diagnostic criteria. The Cervicogenic Headache International Study Group. Headache. 1998;38(6):442-5. 25. Stanton WR, Jull GA. Cervicogenic headache: locus of control and success of treatment. Headache. 2003;43(9):956-61. 26. Martelletti P, van Suijlekom H. Cervicogenic headache: practical approaches to therapy. CNS Drugs. 2004;18(12):793-805. 27. Gradl G, Maier-Bosse T, Penning R, Stabler A. Quantification of C2 cervical spine rotatory fixation by X-ray, MRI and CT. Eur Radiol. 2005;15(2):376-82. 28. Bontrager KL. Textbook of Radiographic Positioning and Related Anatomy. 7th ed. St Louis: Mosby; 2010. 29. Cote P, Cassidy JD, Yong-Hing K, Sibley J, Loewy J. Apophysial joint degeneration, disc degeneration, and sagittal curve of the cervical spine. Can they be measured reliably on radiographs? Spine. 1997;22(8):859-64. 30. Harrison DE, Harrison DD, Cailliet R, Troyanovich SJ, Janik TJ, Holland B. Cobb method or Harrison posterior tangent method: Which to choose for lateral cervical radiographic analysis. Spine. 2000;25(16):2072-8.
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25 31. Rochester RP. Inter and intra-examiner reliability of the upper cervical X-ray marking system: a third and expanded look. CRJ: Chiropractic Research Journal. 1994;3(1):2331. 32. Szeto GPY, Straker L, Raine S. A field comparison of neck and shoulder postures in symptomatic and asymptomatic office workers. Appl Ergon. 2002;33(1):75-84. 33. Jull G, Amiri M, Bullock-Saxton J, Darnell R, Lander C. Cervical musculoskeletal impairment in frequent intermittent headache. Part 1: Subjects with single headaches. Cephalalgia. 2007;27:793-802. 34. Antonaci F. Physical therapy and exercise in headache. Cephalalgia. 2008;28(s1):35. 35. Coskun O, Ucler S, Karakurum B, Atasoy HT, Yildirim T, Ozkan S, et al. Magnetic resonance imaging of patients with cervicogenic headache. Cephalalgia. 2003;23(8):8425. 36. Sjaastad O, Bakketeig LS. Prevalence of cervicogenic headache: Vaga study of headache epidemiology. Acta Neurol Scand. 2008;117(3):173-80. 37. Jull G, O'Leary S, Falla D. Clinical assessment of the deep cervical flexor muscles : the craniocervical flexion test. J Manipulative Physiol Ther. 2008;31(7):525-33. 38. Moore MK. Upper crossed syndrome and its relationship to cervicogenic headache. J Manipulative Physiol Ther. 2004;27(6):414-20. 39. Harrison DD, Harrison DE, Janik TJ, Cailliet R, Ferrantelli J, Haas JW, et al. Modeling of the sagittal cervical spine as a method to discriminate hypolordosis: results of elliptical and circular modeling in 72 asymptomatic subjects, 52 acute neck pain subjects, and 70 chronic neck pain subjects. Spine. 2004;29(22):2485-92. 40. McAviney J, Schulz D, Bock R, Harrison D, Holland B. Determining the relationship between cervical lordosis and neck complaints. J Manipulative Physiol Ther. 2005;28(3):187-93.
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26 41. Jull G, Trott P, Potter H, Zito G, Niere K, Shirley D, et al. A randomized controlled trial of exercise and manipulative therapy for cervicogenic headache Spine. 2002;27:1835-43. 42. Mayoux-Benhamou MA, Revel M, Vallee C, Roudier R, Barbet JP, Bargy F. Longus colli has a postural function on cervical curvature. Surg Radiol Anat. 1994;16:367-71. 43. Jull G, Sterling M, Falla D, Treleaven J, O'Leary S. Whiplash, Headache and Neck pain. Edinburgh: Churchill Livingstone; 2008. 44. Chaibi A, Russell MB. Manual therapies for cervicogenic headache: a systematic review. J Headache Pain. 2012;13(5):351-9. 45. Ylinen J, Nikander R, Nykänen M, Kautiainen H, Häkkinen A. Effect of neck exercises on cervicogenic headache: a randomized controlled trial. J Rehabil Med. 2010;42(4):3449. 46. Beer A, Treleaven J, Jull G. Can a functional postural exercise improve performance in the cranio-cervical flexion test? e A preliminary study. Man Ther. 2012;17:219-24. 47. Falla D, Jull G, Russell T, Vicenzino B, Hodges P. Effect of neck exercise on sitting posture in patients with chronic neck pain. Phys Ther. 2007;87(4):408-17. 48. Park MS, Moon SH, Lee HM, Kim SW, Kim TH, Lee SY, et al. The effect of age on cervical sagittal alignment: normative data on 100 asymptomatic subjects. Spine (Phila Pa 1976). 2013;38(8):E458-63. 49. Matsumoto M, Fujimura Y, Suzuki N, Yoshiaki T, Shiga H. Cervical curvature in acute whiplash injuries: prospective comparative study with asymptomatic subjects. Injury. 1998;29(10):775-8. 50. Helliwell PS, Evans PF, Wright V. The straight cervical spine: does it indicate muscle spasm? J Bone Joint Surg. 1994;76(1):103-6. 51. Bogduk N. Cervicogenic headache: Anatomic basis and pathophysiologic mechanisms. Curr Pain Headache Rep. 2001;5:382-6.
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27 52. Ward TN, Levin M. Case reports: headache caused by a spinal cord stimulator in the upper cervical spine. Headache. 2000;40(8):689-91. 53. Narouze SN, Casanova J, Mekhail N. The longitudinal effectiveness of lateral atlantoaxial intra-articular steroid injection in the treatment of cervicogenic headache. Pain Med. 2007;8(2):184-8. 54. Macpherson BCM, Campbell C. C2 rotation and spinous process deviation in migraine: cause or effect or coincidence? Neuroradiology. 1991;33:475-7. 55. McDonnell MK, Sahrmann SA, Van Dillen L. A specific exercise program and modification of postural alignment for treatment of cervicogenic headache: a case report. J Orthop Sports Phys Ther. 2005;35(1):3-15. 56. Goadsby P, Lipton RB, Ferrari MD. Migraine: current understanding and treatment. N Engl J Med. 2002;346:257-70. 57. Watson DH, Drummond PD. Head pain referral during examination of the neck in migraine and tension-type headache. Headache. 2012;52(8):1226-35. 58. Antonaci F, Ghirmai S, Bono G, Sandrini G, Nappi G. Cervicogenic headache: evaluation of the original diagnostic criteria Cephalalgia. 2001;21:573-83.
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28 Table 1. Major criteria for cervicogenic headache diagnosis recommended by the Cervicogenic Headache International Study Group.
Major criteria for cervicogenic headache diagnosis1 I.
Symptoms and signs of neck involvement: a)
Precipitation of head pain, similar to the usually occurring one: (1)
by neck movement and/or sustained awkward head positioning
(2)
by external pressure over the cervical or occipital region on the symptomatic side
II. III.
b)
Restriction of the range of motion in the neck
c)
Ipsilateral neck, shoulder or arm pain of a rather vague nonradicular nature
Confirmatory evidence by diagnostic anaesthetic blockades2 Unilaterality of head pain without side shift
1
Major criteria as described by Sjaastad et al.24
2
Criteria II was not used in the current study.
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29 Table 2. Comparisons of radiographic postural variables between participants with cervicogenic headache (CGH) and age and gender matched asymptomatic individuals. Radiographic Participant N Mean SD 95% CI P measurement group General cervical CGH 29 8.71 4.6, 16.81 lordosis C2-C7 0.061 1 1 Control 29 5.7 3.7, 9.4 (degrees) Upper cervical CGH 29 11.9 6.5 9.4, 14.3 lordosis C2-C4 0.10 Control 29 9.4 4.3 7.8, 11.1 (degrees) C2 spinous process CGH 29 3.00 1.7 2.4, 3.6 horizontal deviation 0.77 Control 29 2.9 2.0 2.1, 3.6 (mm) 1 Data for general cervical lordosis required non-parametric tests: median and inter-quartile range reported and Wilcoxon rank sum used for comparison between groups
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30 Table 3. Associations between the radiological measurements of the cervical spinal postural variables and the likelihood of experiencing CGH. Postural variable assessed
Likelihood ratio test Chi-square DF
General cervical lordosis C2-C7
4.12
1
Upper cervical lordosis C2-C4
2.86
1
P value 1
0.04 0.09
Odds ratio
95% CI
1.08
1.00, 1.192
1.09
0.99, 1.23
C2 spinous process horizontal 0.11 1 0.74 1.06 0.77, 1.46 deviation 1 Statistical significance, P ≤ 0.05 2 Exact methods (SAS proc logistic) were used to obtain the 95% confidence interval for odds ratio as the Wald statistic provided an interval (0.994, 1.18) for GCL that was inconsistent with the significance indicated by the likelihood ratio test
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31
Figure 1. (a) Example of a general cervical lordosis measurement (Cobb C2-C7 measurement). ‘*’ represents the angle (degrees) used in analysis with a higher value indicating increased lordosis between C2 and C7. (b) Example of an upper cervical lordosis measurement on a radiograph. ‘**’represents the angle (degrees) used in analysis, with a higher value indicating increased lordosis between C2 and C4.
Figure 2. Example of a C2 spinous process horizontal deviation measurement on a radiograph. The perpendicular distance (mm) between the two lines represents the value used in analysis, with a higher value indicating increased C2 spinous process horizontal deviation.
Figure 3. Flow diagram of study participants. CGH = cervicogenic headache.
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Figure 1 a
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Figure 1 b
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Figure 2
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32
Figure 3 Potential participants screened via telephone (n = 300)
CGH* group Most common reasons for exclusion were presence of bilateral headache and/or headache with aura
Control group Most common reason for exclusion was being unable to match age and gender to a participant with CGH
Excluded (n = 239)
Physical assessment to determine eligibility (n = 61)
CGH group None excluded
Control group Excluded (n = 1) Experienced headache during physical assessment and thus not asymptomatic
CGH group based on CHISG† diagnostic criteria (n = 30)
Asymptomatic age and gender matched group (n = 30)
Data analysed (n = 29) One excluded due to digital radiograph technical compromise
Data analysed (n = 29) One excluded due to digital radiograph technical compromise
*CGH – Cervicogenic headache † CHISG – Cervicogenic Headache International Study Group
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An Investigation of Cervical Spinal Posture in Cervicogenic Headache Peter K. Farmer, Suzanne J. Snodgrass, Anthony Buxton and Darren A. Rivett PHYS THER. Published online October 9, 2014 doi: 10.2522/ptj.20140073
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1 Running head: Cervical Spine Posture in Cervicogenic Headache
Research Report
An Investigation of Cervical Spinal Posture in Cervicogenic Headache
Peter K. Farmer, Suzanne J. Snodgrass, Anthony Buxton, Darren A. Rivett
P.K. Farmer, BAppSc(Physio), MMedSc(Physio), Thrive Physiotherapy, Erina, New South Wales, Australia.
S.J. Snodgrass, PT, PhD, MMedSc(Physio), Discipline of Physiotherapy, School of Health Sciences, Faculty of Health and Medicine, Hunter Building, University of Newcastle, University Drive, Callaghan, New South Wales 2308, Australia. Address all correspondence to Dr Snodgrass at: [email protected].
A. Buxton, DipAppSc(Med Rad), MHEd, Discipline of Medical Radiation Science (Diagnostic Radiography), School of Health Sciences, Faculty of Health and Medicine, The University of Newcastle.
D.A. Rivett, PhD, MAppSc(ManipPhty), BAppSc(Phty), Discipline of Physiotherapy, School of Health Sciences, Faculty of Health and Medicine, The University of Newcastle.
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2 [Farmer PK, Snodgrass SJ, Buxton A, Rivett DA. An investigation of cervical spinal posture in cervicogenic headache. Phys Ther. 2015;95:xxx–xxx.]
© 2014 American Physical Therapy Association
Published Ahead of Print: xxx Accepted: October 2, 2014 Submitted: February 24, 2014
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3 ABSTRACT Background. Cervicogenic headache (CGH) is defined as headache symptoms originating from the cervical spine. Cervical dysfunction from abnormal posture has been proposed to aggravate or cause CGH, but there are conflicting reports as to whether there is an association between posture and CGH. Objective. To evaluate differences in cervical spinal posture, measured on radiographs, between patients with probable CGH and asymptomatic control participants. Design. Single blinded comparative measurement design. Methods. Differences in postural variables from radiographs between CGH (n=30) and aged and gender matched asymptomatic control participants (n=30) were determined using paired t-tests or the non-parametric equivalent. Postural variables were general cervical lordosis (GCL, Cobb angle C2-C7), upper cervical lordosis (UCL, sagittal alignment C2 compared with C3-C4) and C2 spinous process horizontal deviation. Logistic regression determined postural variables increasing the likelihood of CGH. Results. There were no significant differences in posture between CGH and controls (mean GCL, CGH group 10.97°, SD 7.50, controls 7.17, SD 5.69, P = 0.06; UCL CGH 11.86°, SD 6.46, controls 9.44, SD 4.28, P = 0.10; C2 spinous process horizontal deviation CGH 3.00mm, SD 1.66, controls 2.86, SD 2.04, P = 0.77). However, there was a significant association between greater GCL and an increased likelihood of having CGH (OR=1.08, 95% CI 1.001, 1.191, P=0.042). Limitations. The findings are limited to an association between GCL and posture, as cause and effect cannot be determined.
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4 Conclusion. The association between greater GCL and increased likelihood of having CGH suggests that GCL might be considered in the management of patients with CGH. However, as the data do not support posture as a cause of CGH, it is unknown whether addressing posture would reduce CGH.
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5
INTRODUCTION Assessment and treatment of posture is common despite there being very little evidence that altered posture is associated with symptoms, or that treatment strategies can improve posture related symptoms.1, 2 The assessment of posture assumes that identifying postures that are different to the ‘ideal’ posture may provide a meaningful clinical sign that may be related to dysfunction and/or symptoms.3 If abnormal posture is not related to dysfunction or symptoms, then the justification of clinical postural assessment is limited. Therefore, research to establish associations between postural variables and symptoms in patients is important for justifying current clinical practices. There are very few postural abnormalities that have been directly related to symptoms.2
Cervicogenic headache (CGH) is a type of secondary headache where the symptoms originate from a dysfunction in the cervical spine.4, 5 Cervical dysfunction from abnormal posture is one factor that has been proposed to aggravate or cause CGH.6, 7 The proposed association between abnormal cervical posture and headache has been demonstrated in migraine and tension type headaches8-10 but there are conflicting results in CGH.1, 11-13 Despite this lack of agreement, clinicians routinely assess and treat altered posture for CGH,1, 2 therefore it is important to examine possible associations in order to guide treatment.
The craniovertebral angle (between the horizontal line passing through C7 and a line extending from the tragus of the ear to the tip of the C7 spinous process10) as measured from photographs has been used to investigate associations between cervical posture and CGH with conflicting results. Two studies in adults reported no
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6 association11, 13 and one study in children aged six to twelve reported an association between a smaller craniovertebral angle (i.e., increased forward head posture) and the presence of CGH.14 This conflicting evidence suggests that craniovertebral angle measurements may not isolate the specific postural factors that may be associated with CGH symptoms.15 Therefore, to determine potential posture variations in patients with CGH, radiographic measurements are needed. Only one identified study used radiographs to assess static cervical lordosis posture in patients with headache and showed that decreased cervical lordosis was associated with tension headaches.16 Tension headache is considered a different headache type to CGH and therefore postural presentations may differ in CGH requiring investigation.
C2 is proposed as the most common cervical level for CGH genesis with both the C1/2 and C2/3 joints suggested as the dominant motion segment.15, 16 The C2/3 motion segment has been reported by some groups to be the most common source of CGH symptoms,5, 17, 18 with diagnostic blocks suggesting the third occipital nerve located at C2/3 was implicated as the pain source in approximately 53% of 15 patients with CGH.19 Alternatively, C1/2 was reliably palpated by two examiners as the symptomatic cervical level in 63% of 60 patients with CGH.20 Two investigations of ‘unilateral’21 and migraine22 headaches that assessed the position and symmetry of the C2 spinous process using imaging (computed tomography and radiography, respectively) have reported that altered C2 spinous process horizontal plane alignment is associated with headaches. However, due to the use of descriptive rather than standardised headache criteria, the participant samples potentially included a mix of headache types, so conclusions about the relationship of C2 spinous process horizontal alignment and CGH cannot be determined.
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7
This aim of this study was to determine if cervical spine posture is altered in patients with CGH as compared to age and gender matched asymptomatic individuals. This is a first step in determining whether posture is worth considering in larger studies that assess the possible contributing factors to CGH symptoms. Determining whether there is a relationship between CGH and cervical posture may potentially provide clinicians with evidence supporting the assessment and treatment of posture in this patient group.
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8 METHODS
A single blind, age and gender matched, comparative measurement design was used to evaluate the differences in cervical spinal posture, as measured on cervical radiographs, between asymptomatic participants (control group) and participants with CGH. Participants were recruited using flyers placed on noticeboards on the university campus where the study was conducted. Interested participants were first screened by telephone for inclusion. The study protocol was approved by the University’s Human Research Ethics Committee and all participants provided written informed consent. No funds were received in support of this work and the authors have no conflict of interest.
Participants Participants were healthy adults aged between 18 and 50 years with a primary complaint of headache and no history of significant medical conditions that might be potential contraindications to physical examination of the cervical spine, including known cancer, osteoporosis, nerve root symptoms, inflammatory or infectious diseases affecting the neck, instability of the cervical spine, or reported potential vertebrobasilar insufficiency symptoms.23 This age range was used so that altered upper neck posture associated with different age groups15 was not a confounding factor in the analysis of posture in the symptomatic and asymptomatic groups. Potential participants who were possibly pregnant were excluded as radiography was to be used in the study. Asymptomatic participants were age and gender matched with CGH participants. Participants with CGH diagnosis were included if their pattern of symptoms was consistent with the diagnostic criteria of the ‘Cervicogenic Headache International Study Group’ (CHISG, Table 1).24 These diagnostic criteria have been used widely as the basis for inclusion in
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9 CGH studies.13, 25, 26 The potential CGH participants were screened by telephone for a pattern of symptoms consistent with the CHISG diagnostic criteria. To be included participants had to have (1) a unilateral headache at least once per week over the previous 2 months (unilaterality consistent on one side, not a headache that swapped sides), (2) which was associated with neck pain before, during or following the headache and (3) aggravated by movement or specific postures of the neck). This description of neck pain is consistent with criteria Ia(1) of the CHISG criteria. Those who experienced an aura with their headache or who were involved in claiming workers’ or third party compensation or litigation were excluded. Those reporting the required pattern of headache symptoms progressed to a physical assessment to determine study eligibility as long as they had also not received any manual therapy treatment for the previous 2 months, as the potential effect of manual therapy on posture is unknown. The physical assessment consisted of an experienced physiotherapist (with professional qualifications in manual therapy and 16 years clinical experience) applying pressure over the spinous and articular processes of the cervical spine with the participant positioned in prone lying. The techniques used for this palpation assessment were common cervical spine posteroanterior passive accessory intervertebral movement assessment techniques.25 A potential participant with headache was eligible if they met the CHISG criterium for the reproduction of “head pain, similar to the usually occurring one” with palpation.24 The identification of patients with CGH thus required potential participants to meet criteria Ia, both (1) and (2), and criteria III of the CHISG criteria (Table 1). Participants may also have met criteria Ib and c, but potential participants were not excluded if they did not meet Ib and c (Table 1). As diagnostic blocks were not used (criteria II, Table 1), participants with CGH were considered to have “probable” CGH, based on the best available diagnostic criteria without the use of invasive techniques. Asymptomatic control participants also underwent the physical palpation assessment to maintain consistency between study groups, as
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10 the possible effects of this palpation assessment on posture are unknown. The therapist performing the physical assessment was blinded as to the headache status of the potential participant. Asymptomatic participants were eligible as long as they did not report any head pain with the physical assessment.
Radiographic Methods The study used radiographic measurements to quantify posture as these methods have been demonstrated to allow specific segmental measurements of cervical spine posture.15, 27 Two standard views of the cervical spine (one anterior-posterior (AP) open mouth view and one lateral view, both in standing) were taken to facilitate generalization to clinical practice. Radiographic examinations were performed by a registered radiographer with 35 years’ experience using standardized positioning techniques and participant instructions.28 The radiographic views and instructions were consistent with a standard cervical radiographic series as performed in clinical radiography practice. Participants were asked to stand in a normal comfortable posture with their arms relaxed, and to look straight ahead. The images were taken in suspended respiration during normal shallow breathing at rest, with the instruction to ‘stop breathing now.’ Participants were not given any instructions for the timing of inspiration or expiration, as forced voluntary breathing causes thoracic cavity movement and body sway, whereas normal involuntary breathing does not result in excessive movement or blurring of the image.28
Radiographs were performed using a Philips Diagnostic Vertical Bucky Stand attached to a Philips Optimus 50 Medium Frequency Generator and Philips R0 1648 Hi-Speed Rotating Anode X-Ray tube in a Philips ROT 360 X-ray Tube Housing (Philips Healthcare, Best, Holland). Two Fuji Computed Radiography (model DS) imaging cassettes were used comprising one 18x24 cm
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11 cassette (for AP open mouth view) and one 24x30cm cassette (for lateral view, Fujifilm Holdings Corporation, Tokyo, Japan). The cassettes contained a standard definition Fuji Digital Image Receptor Plate Model: CR ST-VI (Fujifilm Holdings Corporation, Tokyo, Japan). All images were obtained using a grid technique (105 line/inch 12:1 grid). The lateral view radiographic projection used a focal film distance of 178cm, and for the AP open mouth view 110cm.
Radiographic Measurements The radiographic images were obtained digitally and then transferred to Centricity Webpacs V2.1 (GE Medical Systems, Wisconsin, USA), a software system used to perform measurements. A qualified radiographer experienced in the use of this measurement tool performed all measurements using the same computer and monitor for each participant. A second experienced radiographer repeated the measurements on a subset of 20 randomly selected participants to determine inter-rater reliability of the on-screen measurement techniques. Both radiographers were blinded to the headache status of each participant and the measurements of the other radiographer. Good reliability has been previously demonstrated for these methods when they were performed by drawing on hard copies of radiographs,15, 29-31but is unknown for digitised images using the Centricity Webpacs software.
The posture measurements performed on the lateral radiographic view were general cervical lordosis (GCL) and upper cervical lordosis (UCL). The GCL measurement was based on the ‘Cobb method’.29 It was obtained by drawing lines parallel to the inferior end-plates of C2 and C7 and then the software package generates perpendicular lines to those drawn. The acute angle formed between these lines was calculated by the software package and recorded as GCL (Figure 1a). A higher value for GCL indicated a participant had greater cervical lordosis between C2 and
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12 C7. The UCL radiographic measurement, based on the technique described by Johnson,15 involved drawing a line between the most superior-posterior point on the odontoid process of C2 and the most inferior-posterior point on the body of the second cervical vertebra. A second line was then drawn connecting the most inferior-posterior point on the body of C3 with the most inferior-posterior point on the body of C4. The angle for UCL was determined by measuring the acute angle formed between these two lines (Figure 1b). A higher value for UCL indicated a participant had greater cervical lordosis between C2 and C4. The AP open mouth radiograph view was used to measure the position of the C2 spinous process relative to the midline (Figure 2). This involved a measurement of the distance that the C2 spinous process deviated from the mid-line at the level of the atlas.27 This was determined by drawing two vertical lines: one passing through the mid-point of the tip of the odontoid process and one through the mid-point of the spinous process of C2. The distance between these two lines in mm determined the C2 spinous process deviation, with greater values for increased deviation.
Data Analysis Sample size estimations suggested that potentially meaningful differences of 10° and 5° in GCL29 and UCL15 respectively between groups could be detected with 80% power with 22-24 participants per group. As the variability of C2 spinous process horizontal deviation was unknown, 30 participants per group were recruited. Intraclass correlation coefficients (ICC 2,1) and 95% confidence intervals (CI) determined the inter-tester reliability of the radiographic measurements. Data were checked for normality and non-parametric methods were used where appropriate. Differences in C2 spinous process horizontal deviation and UCL between the CGH group and control group were determined using t-tests. The difference in GCL between groups was determined using the Wilcoxon Rank Sum test.
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13
A matched pairs binary logistic regression determined whether measurements taken of cervical spinal posture on radiographs (GCL, UCL and C2 spinous process horizontal deviation) demonstrated an association with the likelihood of experiencing CGH. Analyses were completed using JMP 10 and SAS 9.2 (SAS Institute, Inc., Cary, NC, USA).
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14 RESULTS Approximately 300 potential participants were screened by telephone using the CHISG criteria (Figure 3). The most common reasons for exclusion were the presence of bilateral headache or an aura. Control participants were only recruited when a participant of the same gender and similar age had already been recruited in the CGH group, so exclusions occurred if matching was not possible. Thirty participants with probable CGH (mean age 31.4 years, SD 10.0 years, 26 females) and 30 age and gender matched controls (mean age 29.8 years, SD 9.4 years, 26 females) were recruited. Participants with CGH reported a mean frequency of 1.2 headaches per week (SD 1.8, range 1 to 7), and a mean duration of 152.4 weeks (SD 311.7, range 2 months to 30 years). All potential CGH group participants who met the telephone screening criteria reported reproduction of their familiar headache on palpation, and were included in the study. Digital radiographs were technically compromised for two participants, one from the CGH group and one from the control group; therefore radiographic data analyses are from 58 participants. The inter -tester reliability of the radiographic measurements was good to excellent: UCL (ICC 0.75, 95% CI .047,0.89), C2 spinous process horizontal deviation (ICC 0.88 95% CI 0.73,.0.95) and GCL (ICC 0.90, 95% CI 0.77, 0.96).
There were no significant differences between the control and CGH groups for the three radiographic postural measurements (Table 2). Logistic regression demonstrated that as the GCL increased there was a statistically significant increased likelihood of having CGH (P = 0.042). The odds ratio of 1.08 (95% CI 1.0 to 1.19) suggests that with each degree increase of GCL, there was an approximate 8% increased likelihood of having CGH in this sample. There were no associations between CGH and UCL or C2 spinous process deviation (Table 3).
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15 DISCUSSION This study is the first to investigate the association between posture and CGH using a radiographic analysis of the cervical spine. The results indicate that cervical spine posture, as defined by the radiographic methods in this study, cannot be used to differentiate between individuals with probable CGH and those who are asymptomatic. However, an increase in GCL was found to be associated with an increased likelihood of experiencing CGH, though UCL and C2 spinous process horizontal deviation were not associated with CGH. The significant variability in cervical spinal posture in the absence of symptoms has been reported to contribute to difficulties in distinguishing postural types between asymptomatic and symptomatic individuals.15, 32 This result is also consistent with a previous study in CGH that indicated that isolated clinical signs were not sufficient to differentiate those with CGH.33 Though the posture variables measured in this study did not differentiate individuals with CGH from those who were asymptomatic, the association between increased GCL and an increased likelihood of having CGH suggests that GCL may be worth considering in assessment of patients with CGH.
Interpreting the odds ratio for the association between GCL and CGH (1.08), each degree of increased lordosis increases the odds of having CGH by 8% (as compared to asymptomatic control participants in this study). However, the 95% CI for the odds ratio (1.0 to 1.19) suggests that there is either no association or the odds of having CGH may be as high as 19% per degree increase in GCL. As the confidence interval for the odds ratio suggests that there may not be an association, the routine assessment of GCL as an isolated clinical sign is not justified. The inability of any single clinical sign or injection procedure to discriminate CGH is consistent with the description of CGH as a syndrome34-36 characterized by a combination of movement, joint and muscle dysfunction.37, 38 However, a combination of clinical signs
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16 (restricted cervical movement, impairment in the craniocervical flexion test and palpable upper cervical joint dysfunction) has been demonstrated to reliably identify CGH.33 The results of the current study suggest that further investigation may be warranted to determine if increased GCL may improve the identification of CGH when considered in combination with other clinical signs.
Previous studies have demonstrated an association between decreased cervical lordosis and tension type headache14 or neck pain.39, 40 In contrast, the present study demonstrated an association between CGH and increased cervical lordosis. This is consistent with a previous study in children that found increased forward head posture as measured by craniovertebral angle (which might be expected to be associated with increased cervical lordosis) was associated with having CGH. These results together suggest that increased cervical lordosis may well be unique to CGH and could be associated with the upper cervical muscle dysfunction that is a feature of CGH.33, 41 One possible theory explaining the relationship between CGL and CGH may be related to muscle dysfunction,42 as upper cervical flexor muscle dysfunction has been established as a feature of CGH,33, 41 and treatments to improve muscle function and control have been demonstrated to be effective in patients with CGH.41, 43-45
However, the effects of improved muscle function on posture in patients with CGH are
unknown, as relationships between improved muscle function and posture have only been demonstrated in patients with neck pain46, 47 and not CGH.
The interpretation of the results of the present study should be made in the light of the results of previous studies investigating cervical lordosis. No previous studies were identified assessing general GCL in patients with CGH using the radiographic C2-C7 Cobb angle
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17 measurement, and few studies in patients with cervical dysfunction. C2-C7 Cobb angles have been reported for patients with neck pain39 and asymptomatic individuals.48 Using similar measurement methods to the current study, Harrison et al.39 found greater lordosis in those with neck pain compared to asymptomatic controls. Harrison et al.39 reported Cobb angles (mean 12.7°, SD 12.5°) in their ‘chronic pain’ group (neck pain symptoms > 12 weeks) that were comparable to the current study (mean 11.0°, SD 7.5°). Conversely, Matsumoto et al. found no difference in the prevalence of lordotic curvature versus non-lordotic curvature in patients with acute whiplash compared to asymptomatic controls, however, these findings were based on observation rather than measurements.49 The GCL values in asymptomatic participants in the current study (mean 7.1, SD 5.7) are consistent with C2-C7 Cobb angles reported by Park et al.48 for their asymptomatic ‘younger’ group (aged 20-29 years, mean 9.0, SD 11.0), but much lower than values reported for asymptomatic participants in the Harrison et al.39 study (mean 26.8, SD 9.7). Harrison et al.39 excluded participants with excessive head protrusion (perpendicular distance from C2 to C7 >25.4mm for their pain groups and >10 mm for their control group), partially explaining the differences. Harrison et al.39 also had a lower proportion of females (50%) compared to the current study (86%), and females have been shown to have greater cervical lordosis than males (demonstrated using different radiographic assessment methods).16, 50 These findings suggest that increased GCL may be a factor in both neck pain and headache, but further research is needed to confirm this.
The lack of statistically significant associations between the two investigated upper cervical spinal postural variables and CGH suggests that despite the upper cervical region being considered the predominant region for the generation of CGH,51-53 symptoms may not be associated with upper cervical postural variations. As increased UCL is one of the
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18 components of forward head posture, these results support the findings of previous investigations that concluded there is no association between forward head posture and CGH,11, 13but contrasts with the study by Budelmann et al.14 showing forward head posture was greater in children with CGH. The current study findings of no association between CGH and C2 spinous process horizontal deviation concurs with one previous study reporting that deviation of the C2 spinous process in headache patients may be coincidental.54 This potentially means that other impairments in the upper cervical region (e.g. muscular dysfunction) may instead be contributing to symptoms, rather than localised postural characteristics. Further, the association of GCL with CGH despite expectations that the UCL would be more likely involved is consistent with a previous case study that reported improvements in CGH following treatment to improve general posture.55 One hypothesis may be that altered general posture contributes to the likelihood of CGH due to the effects on larger muscle groups (e.g., levator scapulae) that attach to the upper cervical levels.
Limitations The participants in this study were recruited via advertisements rather than patients presenting at a clinic, which may bias the results. However strict selection criteria were used, based on the CHISG major criteria for CGH diagnosis.24 The CHISG recommends the use of diagnostic anaesthetic blockades to provide a definitive CGH diagnosis,24 which this study did not employ. Previous studies have also not used diagnostic anaesthetic blockades as they are considered invasive and associated with unjustifiable risk in the research setting with volunteer participants.13, 43 Moreover, diagnostic anaesthetic blockades abolish other types of headaches56 and therefore do not establish an unequivocal CGH diagnosis. They also rely on the participant presenting for assessment at the time they are experiencing symptoms. Participants were included in the current study if they regularly experienced CGH, rather than
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19 if they had a presenting headache, and the presence or absence of CGH symptoms at the time the radiograph was taken were not recorded. As CGH is typically an intermittent headache that does not occur in a predictable cycle and patients often present in the clinical setting during symptom-free periods, it was considered important to investigate posture irrespective of participants’ symptoms at the time of assessment. Furthermore, though the reproduction of a participant’s familiar headache was used as one assessment component to identify patients with CGH as recommended in the CHISG diagnostic criteria, it is acknowledged that pain on palpation of the cervical spine may also occur in patients with other types of headaches, suggesting this criterion is not specific to CGH.57 The reproduction of familiar headache by palpation was used in addition to the descriptors consistent with CGH as described in the CHISG criteria as an additional component supporting the likelihood of a participant’s headache being cervical in origin, as in a previous study.58 In terms of the possible confounders of the posture measurements, the radiographs in this study were not assessed for pathology so other possible contributors to the presenting postures cannot be determined. Furthermore, the palpation assessment may have also been a confounding factor, as the effect of palpation on posture is unknown. To minimise the potential for confounding, the palpation assessment was performed on all participants using the same method and in the same sequence regardless of the participant’s headache status. Lastly, as this study was a comparative study design, only an association between posture and CGH can be demonstrated, and it is unknown whether increased GCL posture causes CGH or having CGH leads to an increase in GCL. Additional factors that may contribute to symptoms, such as psychosocial variables, were not explored in this study, therefore the interpretation of the results is limited to the possible association of posture to symptoms.
Future Research
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20 Future investigations could aim to determine if the postural association identified in the current study is a causative factor for CGH or instead a response to symptoms, and if changing the GCL has an effect on symptoms. Additionally, a larger multifactorial study may investigate posture with other possible factors influencing the development of symptoms, such as psychosocial factors. Further research into cervical posture using radiographs in other headache types may help determine whether posture could be useful for diagnostic differentiation of headache types. Research may also focus on the potential relationships between upper cervical muscle dysfunction and posture, which might direct future treatment strategies in CGH.
Conclusion The present study found that three components of static cervical spinal posture commonly used clinically cannot be used to discriminate participants with CGH from asymptomatic individuals. However, increased GCL was associated with an increased likelihood of having CGH. Therefore, clinicians may consider GCL when assessing or treating patients with CGH. It should be noted that the results of this study suggest the degree of GCL cannot identify a patient with CGH so the routine assessment of GCL in all patients with CGH is not supported.
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21 Acknowledgments All authors provided concept/idea/research design, writing, and data collection. Mr Farmer, Dr Snodgrass, and Mr Buxton provided data analysis. Mr Farmer and Mr Rivett provided project management. Dr Snodgrass and Mr Buxton provided facilities/equipment. Dr Snodgrass, Mr Buxton, and Mr Rivett provided consultation (including review of the manuscript before submission). The authors acknowledge John Tessier for his assistance with data collection.
An abstract of the study was presented at the Musculoskeletal Physiotherapy Australia 16th Biennial Conference; October 1-5, 2009; Sydney, Australia.
DOI: 10.2522/ptj.20140073
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22
References 1.
Christensen ST, Hartvigsen J. Spinal curves and health: A systematic critical review of the epidemiological literature dealing with associations between sagittal spinal curves and health. J Manipulative Physiol Ther. 2008;31(9):690-714.
2.
Refshauge K, Gass E. Musculoskeletal Physiotherapy - Clinical science and evidencebased practice. 2nd ed. Oxford: Butterworth Heinemann; 2004.
3.
Troyanovich SJ, Harrison DE, Harrison DD. Structural rehabilitation of the spine and posture: rationale for treatment beyond the resolution of symptoms. J Manipulative Physiol Ther. 1998;21(1):37-50.
4.
Antonaci F, Sjaastad O. Cervicogenic headache: a real headache. Curr Neurol Neurosci Rep. 2011;11(2):149-55.
5.
Bogduk N, Govind J. Cervicogenic headache: an assessment of the evidence on clinical diagnosis, invasive tests, and treatment. Lancet Neurol. 2009 Oct;8(10):959-68.
6.
Richardson CJ. Treatment of cervicogenic headaches using Mulligan "SNAGS" and postural re-education: a case report. Orthopaedic Physical Therapy Practice. 2009;21(1):33-8.
7.
Jull G. Management of cervical headache. Man Ther. 1997;2(4):182-90.
8.
Fernandez-de-las-Penas C, Alonso-Blanco C, Cuadrado ML, Pareja JA. Forward head posture and neck mobility in chronic tension-type headache: a blinded, controlled study. Cephalalgia. 2005;26:314-9.
9.
Fernandez-de-Las-Penas C, Cuadrado ML, Pareja JA. Myofascial trigger points, neck mobility and forward head posture in unilateral migraine. Cephalalgia. 2006;26(9):106170.
Downloaded from http://ptjournal.apta.org/ by Barbara Shipman on October 16, 2014
23 10. Fernandez-de-Las-Penas C, Cuadrado ML, Pareja JA. Myofascial trigger points, neck mobility, and forward head posture in episodic tension-type headache. Headache. 2007;47(5):662-72. 11. Dumas JP, Arsenault AB, Boudreau G, Magnoux E, Lepage Y, Bellavance A, et al. Physical impairments in cervicogenic headache: traumatic vs. nontraumatic onset. Cephalalgia. 2001;21(9):884-93. 12. Watson DH, Trott PH. Cervical headache: an investigation of natural head posture and upper cervical flexor muscle performance. Cephalalgia. 1993;13:272-84. 13. Zito G, Jull G, Story I. Clinical tests of musculoskeletal dysfunction in the diagnosis of cervicogenic headache Man Ther. 2006;11(2):118-29. 14. Budelmann K, von Piekartz H, Hall T. Is there a difference in head posture and cervical spine movement in children with and without pediatric headache? Eur J Pediatr. 2013;172:1349-56. 15. Johnson GM. The correlation between surface measurement of head and neck posture and the anatomic position of the upper cervical vertebrae. Spine. 1998;23(8):921-7. 16. Nagasawa A, Sakakibara T, Takahashi A. Roentgenographic findings of the cervical spine in tension-type headache. Headache. 1993;33:90-5. 17. Cooper G, Bailey B, Bogduk N. Cervical Zygapophysial Joint Pain Maps. Pain Med. 2007;8(4):344-53. 18. Jull G. Manual diagnosis of C2/3 headache. Cephalalgia. 1985;5(3):308-9. 19. Lord SM, Barnsley L, Wallis BJ, Bogduk N. Third occipital nerve headache: a prevalence study. J Neurol Neurosurg Psychiatry. 1994;57(10):1187-90. 20. Hall T, Briffa K, Hopper D, Robinson K. Reliability of manual examination and frequency of symptomatic cervical motion segment dysfunction in cervicogenic headache. Man Ther. 2010;15:542-6.
Downloaded from http://ptjournal.apta.org/ by Barbara Shipman on October 16, 2014
24 21. Boquet J, Moore N, Payennville G, Leclerc D, Montier F, Boismare F. Use of CT scans in the study of the upper cervical vertebrae in strictly lateralised migrainous headache (and other intermittent headache?) In: Rose FC, editor. New advances in headache research. London: Smith-Gordon and Company 1989. p. 45-8. 22. Boquet J, Biosmare F, Payenneville G, Leclerc D, Monnier J, Moore N. Lateralization of headache: Possible role of upper cervical trigger point. Cephalalgia. 1989;9:15-24. 23. Murtagh JE, Kenna CJ. Back Pain & Spinal Manipulation. 2nd ed. Oxford: Butterworth Heinemann; 2001. 24. Sjaastad O, Fredriksen TA, Pfaffenrath V. Cervicogenic headache: Diagnostic criteria. The Cervicogenic Headache International Study Group. Headache. 1998;38(6):442-5. 25. Stanton WR, Jull GA. Cervicogenic headache: locus of control and success of treatment. Headache. 2003;43(9):956-61. 26. Martelletti P, van Suijlekom H. Cervicogenic headache: practical approaches to therapy. CNS Drugs. 2004;18(12):793-805. 27. Gradl G, Maier-Bosse T, Penning R, Stabler A. Quantification of C2 cervical spine rotatory fixation by X-ray, MRI and CT. Eur Radiol. 2005;15(2):376-82. 28. Bontrager KL. Textbook of Radiographic Positioning and Related Anatomy. 7th ed. St Louis: Mosby; 2010. 29. Cote P, Cassidy JD, Yong-Hing K, Sibley J, Loewy J. Apophysial joint degeneration, disc degeneration, and sagittal curve of the cervical spine. Can they be measured reliably on radiographs? Spine. 1997;22(8):859-64. 30. Harrison DE, Harrison DD, Cailliet R, Troyanovich SJ, Janik TJ, Holland B. Cobb method or Harrison posterior tangent method: Which to choose for lateral cervical radiographic analysis. Spine. 2000;25(16):2072-8.
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25 31. Rochester RP. Inter and intra-examiner reliability of the upper cervical X-ray marking system: a third and expanded look. CRJ: Chiropractic Research Journal. 1994;3(1):2331. 32. Szeto GPY, Straker L, Raine S. A field comparison of neck and shoulder postures in symptomatic and asymptomatic office workers. Appl Ergon. 2002;33(1):75-84. 33. Jull G, Amiri M, Bullock-Saxton J, Darnell R, Lander C. Cervical musculoskeletal impairment in frequent intermittent headache. Part 1: Subjects with single headaches. Cephalalgia. 2007;27:793-802. 34. Antonaci F. Physical therapy and exercise in headache. Cephalalgia. 2008;28(s1):35. 35. Coskun O, Ucler S, Karakurum B, Atasoy HT, Yildirim T, Ozkan S, et al. Magnetic resonance imaging of patients with cervicogenic headache. Cephalalgia. 2003;23(8):8425. 36. Sjaastad O, Bakketeig LS. Prevalence of cervicogenic headache: Vaga study of headache epidemiology. Acta Neurol Scand. 2008;117(3):173-80. 37. Jull G, O'Leary S, Falla D. Clinical assessment of the deep cervical flexor muscles : the craniocervical flexion test. J Manipulative Physiol Ther. 2008;31(7):525-33. 38. Moore MK. Upper crossed syndrome and its relationship to cervicogenic headache. J Manipulative Physiol Ther. 2004;27(6):414-20. 39. Harrison DD, Harrison DE, Janik TJ, Cailliet R, Ferrantelli J, Haas JW, et al. Modeling of the sagittal cervical spine as a method to discriminate hypolordosis: results of elliptical and circular modeling in 72 asymptomatic subjects, 52 acute neck pain subjects, and 70 chronic neck pain subjects. Spine. 2004;29(22):2485-92. 40. McAviney J, Schulz D, Bock R, Harrison D, Holland B. Determining the relationship between cervical lordosis and neck complaints. J Manipulative Physiol Ther. 2005;28(3):187-93.
Downloaded from http://ptjournal.apta.org/ by Barbara Shipman on October 16, 2014
26 41. Jull G, Trott P, Potter H, Zito G, Niere K, Shirley D, et al. A randomized controlled trial of exercise and manipulative therapy for cervicogenic headache Spine. 2002;27:1835-43. 42. Mayoux-Benhamou MA, Revel M, Vallee C, Roudier R, Barbet JP, Bargy F. Longus colli has a postural function on cervical curvature. Surg Radiol Anat. 1994;16:367-71. 43. Jull G, Sterling M, Falla D, Treleaven J, O'Leary S. Whiplash, Headache and Neck pain. Edinburgh: Churchill Livingstone; 2008. 44. Chaibi A, Russell MB. Manual therapies for cervicogenic headache: a systematic review. J Headache Pain. 2012;13(5):351-9. 45. Ylinen J, Nikander R, Nykänen M, Kautiainen H, Häkkinen A. Effect of neck exercises on cervicogenic headache: a randomized controlled trial. J Rehabil Med. 2010;42(4):3449. 46. Beer A, Treleaven J, Jull G. Can a functional postural exercise improve performance in the cranio-cervical flexion test? e A preliminary study. Man Ther. 2012;17:219-24. 47. Falla D, Jull G, Russell T, Vicenzino B, Hodges P. Effect of neck exercise on sitting posture in patients with chronic neck pain. Phys Ther. 2007;87(4):408-17. 48. Park MS, Moon SH, Lee HM, Kim SW, Kim TH, Lee SY, et al. The effect of age on cervical sagittal alignment: normative data on 100 asymptomatic subjects. Spine (Phila Pa 1976). 2013;38(8):E458-63. 49. Matsumoto M, Fujimura Y, Suzuki N, Yoshiaki T, Shiga H. Cervical curvature in acute whiplash injuries: prospective comparative study with asymptomatic subjects. Injury. 1998;29(10):775-8. 50. Helliwell PS, Evans PF, Wright V. The straight cervical spine: does it indicate muscle spasm? J Bone Joint Surg. 1994;76(1):103-6. 51. Bogduk N. Cervicogenic headache: Anatomic basis and pathophysiologic mechanisms. Curr Pain Headache Rep. 2001;5:382-6.
Downloaded from http://ptjournal.apta.org/ by Barbara Shipman on October 16, 2014
27 52. Ward TN, Levin M. Case reports: headache caused by a spinal cord stimulator in the upper cervical spine. Headache. 2000;40(8):689-91. 53. Narouze SN, Casanova J, Mekhail N. The longitudinal effectiveness of lateral atlantoaxial intra-articular steroid injection in the treatment of cervicogenic headache. Pain Med. 2007;8(2):184-8. 54. Macpherson BCM, Campbell C. C2 rotation and spinous process deviation in migraine: cause or effect or coincidence? Neuroradiology. 1991;33:475-7. 55. McDonnell MK, Sahrmann SA, Van Dillen L. A specific exercise program and modification of postural alignment for treatment of cervicogenic headache: a case report. J Orthop Sports Phys Ther. 2005;35(1):3-15. 56. Goadsby P, Lipton RB, Ferrari MD. Migraine: current understanding and treatment. N Engl J Med. 2002;346:257-70. 57. Watson DH, Drummond PD. Head pain referral during examination of the neck in migraine and tension-type headache. Headache. 2012;52(8):1226-35. 58. Antonaci F, Ghirmai S, Bono G, Sandrini G, Nappi G. Cervicogenic headache: evaluation of the original diagnostic criteria Cephalalgia. 2001;21:573-83.
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28 Table 1. Major criteria for cervicogenic headache diagnosis recommended by the Cervicogenic Headache International Study Group.
Major criteria for cervicogenic headache diagnosis1 I.
Symptoms and signs of neck involvement: a)
Precipitation of head pain, similar to the usually occurring one: (1)
by neck movement and/or sustained awkward head positioning
(2)
by external pressure over the cervical or occipital region on the symptomatic side
II. III.
b)
Restriction of the range of motion in the neck
c)
Ipsilateral neck, shoulder or arm pain of a rather vague nonradicular nature
Confirmatory evidence by diagnostic anaesthetic blockades2 Unilaterality of head pain without side shift
1
Major criteria as described by Sjaastad et al.24
2
Criteria II was not used in the current study.
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29 Table 2. Comparisons of radiographic postural variables between participants with cervicogenic headache (CGH) and age and gender matched asymptomatic individuals. Radiographic Participant N Mean SD 95% CI P measurement group General cervical CGH 29 8.71 4.6, 16.81 lordosis C2-C7 0.061 1 1 Control 29 5.7 3.7, 9.4 (degrees) Upper cervical CGH 29 11.9 6.5 9.4, 14.3 lordosis C2-C4 0.10 Control 29 9.4 4.3 7.8, 11.1 (degrees) C2 spinous process CGH 29 3.00 1.7 2.4, 3.6 horizontal deviation 0.77 Control 29 2.9 2.0 2.1, 3.6 (mm) 1 Data for general cervical lordosis required non-parametric tests: median and inter-quartile range reported and Wilcoxon rank sum used for comparison between groups
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30 Table 3. Associations between the radiological measurements of the cervical spinal postural variables and the likelihood of experiencing CGH. Postural variable assessed
Likelihood ratio test Chi-square DF
General cervical lordosis C2-C7
4.12
1
Upper cervical lordosis C2-C4
2.86
1
P value 1
0.04 0.09
Odds ratio
95% CI
1.08
1.00, 1.192
1.09
0.99, 1.23
C2 spinous process horizontal 0.11 1 0.74 1.06 0.77, 1.46 deviation 1 Statistical significance, P ≤ 0.05 2 Exact methods (SAS proc logistic) were used to obtain the 95% confidence interval for odds ratio as the Wald statistic provided an interval (0.994, 1.18) for GCL that was inconsistent with the significance indicated by the likelihood ratio test
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31
Figure 1. (a) Example of a general cervical lordosis measurement (Cobb C2-C7 measurement). ‘*’ represents the angle (degrees) used in analysis with a higher value indicating increased lordosis between C2 and C7. (b) Example of an upper cervical lordosis measurement on a radiograph. ‘**’represents the angle (degrees) used in analysis, with a higher value indicating increased lordosis between C2 and C4.
Figure 2. Example of a C2 spinous process horizontal deviation measurement on a radiograph. The perpendicular distance (mm) between the two lines represents the value used in analysis, with a higher value indicating increased C2 spinous process horizontal deviation.
Figure 3. Flow diagram of study participants. CGH = cervicogenic headache.
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Figure 1 a
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Figure 1 b
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Figure 2
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32
Figure 3 Potential participants screened via telephone (n = 300)
CGH* group Most common reasons for exclusion were presence of bilateral headache and/or headache with aura
Control group Most common reason for exclusion was being unable to match age and gender to a participant with CGH
Excluded (n = 239)
Physical assessment to determine eligibility (n = 61)
CGH group None excluded
Control group Excluded (n = 1) Experienced headache during physical assessment and thus not asymptomatic
CGH group based on CHISG† diagnostic criteria (n = 30)
Asymptomatic age and gender matched group (n = 30)
Data analysed (n = 29) One excluded due to digital radiograph technical compromise
Data analysed (n = 29) One excluded due to digital radiograph technical compromise
*CGH – Cervicogenic headache † CHISG – Cervicogenic Headache International Study Group
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An Investigation of Cervical Spinal Posture in Cervicogenic Headache Peter K. Farmer, Suzanne J. Snodgrass, Anthony Buxton and Darren A. Rivett PHYS THER. Published online October 9, 2014 doi: 10.2522/ptj.20140073
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