Transcript Physical Exam and Self-Reported Pain outcomes from a

Physical Exam and Self-Reported Pain outcomes from a
Randomized Trial on Chronic Cervicogenic Headache
Darcy Vavrek ND MS1
Mitch Haas DC MA1
Dave Peterson DC1
1Western
States Chiropractic College, Portland Oregon
Funded by NCCAM NIH R21AT002324
Cervicogenic headache (CHA)
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Cervicogenic headache (CHA) is a type of
headache causally associated with cervical
myofascial tender spots combined with cervical
spine dysfunction.
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(Headache Classification Subcommittee of the International Headache Society 2004)
The reported prevalence of CHA varies from
13.8% to 17.8% of the headache population in
different epidemiological studies.
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(Anthony 2000, Nilsson 1995, Pfaffenrath 1990)
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Spinal Manipulative Therapy and CHA
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The scientific evidence on SMT for the relief of
chronic headache has been well discussed in systematic
reviews of randomized trials.
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(Hurwitz 1996, Vernon 1999, Bronfort 2001, Astin 2002, Bronfort 2004, Lenssinck 2004,
Fernandez-de-Las-Penas 2005 & 2006)
These reviews looked at patient self-reported outcomes
when evaluating treatment effect such as pain intensity,
headache index, frequency, duration, and improvement.
Missing were any objective outcomes that could be
measured by the treating physician.
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Objectives of analysis project
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Headache pain studies use subject self-reported outcomes to
assess treatment efficacy.
Objective clinical measures for studies of CHA pain have not
been established.
What do objective physical measures reveal and how do they
associate with self-reported outcomes?
In this analysis, we investigate relationships between objective
physical exam measures with self-reported CHA outcomes.
Associations between PE and self-reported outcomes were
evaluated using linear models, adjusting for socio-demographic
differences and study group.
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The RCT that generated the data
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This is a secondary analysis of an open-label randomized
controlled pilot study with 80 subjects randomized to 8 or 16
treatments of spinal manipulative therapy or light massage
control over 8 weeks.
Forty of 80 subjects were randomized to 8 treatments (spinal
manipulative therapy or light massage control) and 8 PE over 8
weeks.
Physical examinations by the study chiropractor served as an
attention and physical contact control for the 40 subjects
randomized to receive care once a week for 8 weeks.
The remaining subjects received no follow-up PE.
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Subjective outcomes
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Self-reported outcomes included
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CHA and neck
Pain
 Disability
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Neck
Pain
 Disability
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Number of CHA headaches
 Related CHA disability days
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Physical Exam measures
Active cervical range of motion and associated pain
 Motion palpation of the spine
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cervical region
 upper thoracic region
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Algometric pain threshold evaluated over articular
pillars/ transverse processes
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Baseline summary
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Participants tended to be young (37 ± 11), white, nonHispanic (75%) women (78%).
There were notable differences in race and smoking at
baseline
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There were no differences between group means in the
subjective outcomes
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these will be used as covariates in the main analysis
The mean CHA pain intensity and functional disability were
54.0 and 48.3 respectively.
The sample averaged approximately fifteen CHAs per month
There were no clinically important differences between
group means for physical exam outcomes
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Baseline summary
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Participants tended to have
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cervical range of motion pain of 1.4 on a zero to ten pain scale
20o of restricted extension cervical range of motion
4 total endplay restrictions of some kind
pain pressure threshold of 3.2 kg
pain score from orthopedic tests for midline pain of 0.7 on a zero to ten
pain scale
pain score of 1.1 across all ten point scale physical exam pain measures
Only two physical exam variables showed statistically significant
differences between group means after adjusting for smoking
and race
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sitting rotation endplay restriction for C6-7 to C7-T1 left and right
(p=.034 and .028 respectively).
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Final outcome summary
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While many physical exam measures showed a minor
advantage of the SMT group over the LM group, on average,
there were only two PE measures whose mean treatment
group differences were statistically significant.
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Pain on Cervical ROM Right Rotation (mean difference 1.1, p=.025)
Pain on Cervical ROM Flexion (mean difference 1.1, p=.025)
Both these measures favor SMT after adjusting for race, smoking,
and baseline physical exam measure.
Cervical ROM extension remains restricted in both groups by
about 20o.
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Final Outcome Summary
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Also, there are some differences noted in
subjective outcome group means reported in our
paper submitted to Spine Journal.
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(Haas – in review)
We decided to adjust for study treatment group
as well as smoking and race in our main analysis
models.
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Results of Main Analysis
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Cervical active ROM pain measures
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were associated with neck pain intensity and disability, CHA frequency, and disability days at baseline.
Neck pain and disability
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Cervical active ROM measures
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was associated with CHA pain and disability, neck pain and disability, CHA frequency and disability days
at week 12 and moderately associated in surrounding weeks.
Compression tests for midline pain
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was associated with CHA frequency and disability days at baseline and faded over time.
Pain Pressure Threshold (PPT)
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predicted CHA frequency and disability days well in the beginning, but this faded over time.
remained predictive of CHA frequency throughout study.
Sitting rotation endplay restriction
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were not measured at weeks 4 & 8
were no longer strongly associated at weeks 12 & 24
were moderately associated with questionnaire outcomes with no clear pattern.
Distraction test associations
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were limited by the fact that all participants score zero on their distraction test at their final physical
exam.
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Discussion
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Physical exam measures of cervical ROM pain
and net cervical ROM
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Pain pressure thresholds
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were most associated with subjective headache
experience near baseline, p<.001 to .038.
were most associated with subjective outcomes
at/after week 12, p=.001 to .035.
The pattern shifts at about week 12, four weeks
after the final treatment
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Cervical ROM
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Cervical ROM and pain on cervical ROM might be expected to be more predictive for
higher pain levels early on, since splinting may be an effect.
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Later on, with lower pain and some manual medicine related increased cervical ROM,
cervical ROM and pain on cervical ROM would be expected to have a lesser
relationship.
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This association did not happen in all participants since, 11 out of 40 participants (~25%)
reported no pain on cervical ROM at baseline.
Yet those who had pain on cervical ROM also had worse subjective outcomes at baseline.
However, with the improvement of most study participants, zero pain reported on cervical
ROM increased to 20 out of 40 participants (~50%) at their final physical exam
It is difficult to establish any type of linear relationship.
It is tempting to say that manipulation improved range of motion and the pain
associated with range of motion and decreased the subject’s headaches because
manipulation is directed at improving joint mobility and function.
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However, both treatment groups improved with time and we were not powered to detect
this type of effect.
Future studies that include cervical range of motion and associated pain as baseline and final
secondary outcomes in a study, measured by a blinded study physician, will allow clinicians to
address these unanswered questions.
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Pain Pressure Threshold
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The fact that pain pressure threshold is not a good baseline
predictor of baseline subjective outcomes in our subject
population is puzzling.
At 12 weeks, pressure over paraspinal soft tissues and over the
joints was perhaps more associated with persistent headache
outcomes because other musculoskeletal components associated
with the neck pain and headaches were not fully affected by
thrust manipulation which potentially has more therapeutic
effect on joint mobility.
Yet, we were underpowered to detect this type of result and both
treatment groups experienced this change in association.
Still, for the practicing clinician, it is likely that those with a low
pain pressure threshold may also have worse subjective
experiences and thus be candidates for further manual care.
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No potential surrogates noted
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No one physical exam measure remained predictive of
the self-reported headache discomfort questions over
time.
This is likely due to patient improvement.
Thus, no single objective physical exam surrogate
measure for CHA clinical research is suggested by this
study as a useful longitudinal outcome.
Further analysis of the data will assess if these baseline
physical exam measures are predictive of treatment
outcome.
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Cervical extension
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Both groups remained restricted on cervical
extension after treatment, 20o restriction on
average.
Perhaps decreased cervical ROM on extension is
indicative of the population of those who might
suffer from chronic cervicogenic headaches and
could be a future focus of treatment assessment.
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Limitations
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Blinding
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Treating physicians performing the attention control physical
exam
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were not blinded to treatment arm after baseline
could have performed biased assessment
may have expected improvement based on
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time in the study
treatment group assignment.
Small sample, 20 patients per treatment arm.
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Minimal power to detect the associations we’ve looked for
Results need to be repeated by larger studies
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To further flush out the pathophysiology of cervicogenic headache.
Physical exam variables could be a secondary outcome
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Limitations
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Generalizability
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Subjects
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selected by rigid randomized clinical trial protocol
enrolled in the study went through
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a phone screen
two baseline exams
had to meet study criteria before enrollment
Larger clinical trials on headache populations that
gather longitudinal physical exam data will help to
establish the generalizability of these results.
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Conclusions
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We noted that provocative cervical ROM pain was most
predictive of the baseline headache experience.
However, 4 weeks after treatment, algometric pain thresholds
were most predictive.
No one PE measure remained predictive of the self-reported
headache outcomes over time.
Clinically important changes over time were observed in physical
exam indicators for self-reported CHA pain and disability
outcomes.
This is an important step towards establishing objective
measures of CHA pain and disability for clinical studies.
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References
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Anthony M. Cervicogenic headache: Prevalence and response to local steroid therapy. Clin Exp Rheumatol. 2000; 18:S59-64.
Astin JA, Ernst E. The effectiveness of spinal manipulation for the treatment of headache disorders: A systematic review of
randomized clinical trials. Cephalalgia. 2002;22:617-623.
Bronfort G, Assendelft WJ, Evans R, Haas M, Bouter L. Efficacy of spinal manipulation for chronic headache: A systematic
review. J Manipulative Physiol Ther. 2001;24:457-466.
Bronfort G, Nilsson N, Haas M, et al. Non-invasive physical treatments for chronic/recurrent headache. Cochrane Database Syst Rev.
2004;(3):CD001878.
Fernandez-de-Las-Penas C, Alonso-Blanco C, Cuadrado ML, Miangolarra JC, Barriga FJ, Pareja JA. Are manual therapies effective
in reducing pain from tension-type headache?: A systematic review. Clin J Pain. 2006;22:278-285.
Fernandez-de-Las-Penas C, Alonso-Blanco C, Cuadrado ML, Pareja JA. Spinal manipulative therapy in the management of
cervicogenic headache. Headache. 2005;45:1260-1263.
Haas M, Spegman A, Peterson DH, Aickin M, Vavrek D. Dose-response and efficacy of spinal manipulation for chronic
cervicogenic headache. Spine Journal. (in review).
Headache Classification Subcommittee of the International Headache Society. The international classification of headache
disorders, 2nd edition. Cephalalgia. 2004; 24:8-160. Available from:
Hurwitz EL, Aker PD, Adams AH, Meeker WC, Shekelle PG. Manipulation and mobilization of the cervical spine. A systematic
review of the literature. Spine. 1996;21:1746-59; discussion 1759-60.
Lenssinck ML, Damen L, Verhagen AP, Berger MY, Passchier J, Koes BW. The effectiveness of physiotherapy and manipulation in
patients with tension-type headache: A systematic review. Pain. 2004;112:381-388.
Nilsson N. The prevalence of cervicogenic headache in a random population sample of 20-59 year olds. Spine. 1995; 20:18841888.
Pfaffenrath V, Kaube H. Diagnostics of cervicogenic headache. Funct Neurol. 1990; 5:159-164.
Vernon H, McDermaid CS, Hagino C. Systematic review of randomized clinical trials of complementary/alternative therapies in
the treatment of tension-type and cervicogenic headache. Complement Ther Med. 1999;7:142-155.
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