EUR J PHYS REHABIL MED 2014;50:641-7 Effect of manual therapy techniques on headache disability in patients with tension-type headache. Randomized controlled trial Background. Tension-type headache (TTH) is the most common type of primary headache however there is no clear evidence as to which specific treatment is most effective or whether combined treatment is more effective than individual treatments. Aim. To assess the effectiveness of manual therapy techniques, applied to the suboccipital region, on aspects of disability in a sample of patients with tension-type headache. Design. Randomized Controlled Trial. Setting. Specialized centre for headache treatment. Population. Seventy-six (62 women) patients (age: 39.9 ± 10.9 years) with episodic chronic TTH. Methods. Patients were randomly divided into four treatment groups: 1) suboccipital soft tissue inhibition; 2) occiput-atlas-axis manipulation; 3) combined treatment of both techniques; 4) control. Four sessions were applied over 4 weeks and disability was assessed before and after treatment using the Headache Disability Inventory (HDI). Headache frequency, severity and the functional and emotional subscales of the questionnaire were assessed. Photophobia, phonophobia and pericranial tenderness were also monitored. Results. Headache frequency was significantly reduced with the manipulative and combined treatment (P<0.05), and the severity and functional subscale of the HDI changed in all three treatment groups (P<0.05). Manipulation treatment also reduced the score on the emotional subscale of the HDI (P<0.05). The combined intervention showed a greater effect at reducing the overall HDI score compared to the group that received suboccipital soft tissue inhibition and to the control group (both P<0.05). In addition, photophobia, pho- Corresponding author: D. Falla, Pain Clinic, Center for Anesthesiology, Emergency and Intensive Care Medicine, University Hospital Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany. E-mail: deborah.falla@bccn.uni-goettingen.de G. V. 1, C. RODRÍGUEZ-BLANCO 2, A. OLIVA-PASCUAL-VACA 2 J. C. BENÍTEZ-MARTÍNEZ 1, E. LLUCH 1, D. FALLA 3, 4 1Department of Physical Therapy University of Valencia, Valencia, Spain 2Department of Physical Therapy University of Sevilla, Sevilla, Spain 3Pain Clinic, Center for Anesthesiology Emergency and Intensive Care Medicine University Hospital Göttingen, Göttingen, Germany 4Department of Neurorehabilitation Engineering Bernstein Center for Computational Neuroscience University Medical Center Göttingen Georg August University, Göttingen, Germany nophobia and pericranial tenderness only improved in the group receiving combined therapy (P<0.05). Conclusion. When given individually, suboccipital soft tissue inhibition and occiput-atlas-axis manipulation resulted in changes in different parameters related to the disability caused by TTH. However, when the two treatments were combined, effectiveness was noted for all aspects of disability and other symptoms including photophobia, phonophobia and pericranial tenderness. Clinical Rehabilitation Impact. Although individual manual therapy treatments showed a positive change in headache features, measures of photophobia, photophobia and pericranial tenderness only improved in the group that received the combined treatment suggesting that combined treatment is the most appropriate for symptomatic relief of TTH. Key words: Treatment outcome - Tension-type headache - Manipulations. Primary headaches are highly prevalent among the population. Among these, tension-type headache (TTH) is the most common, producing a major Vol. 50 - No. 6 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE 641
social and economic impact, 1 with implications for work, social life, daily activities, and ultimately, quality of life. 2 Pericranial muscle contracture and stress play a major role in the pathophysiology of TTH, involving peripheral and central sensitization mechanisms, justifying the presence of painful pericranial tenderness and a decreased pain threshold in this region. 3 The most common non-pharmacological treatments for the relief of TTH with demonstrated efficacy are manual procedures such as spinal manipulation, massage, connective tissue massage, spinal mobilization and manual traction. 4 However, further evidence 5 supporting the effectiveness of manual therapy techniques for the management of headache is necessary. Most studies evaluating the effectiveness of manual therapy have employed combined techniques, thus there is no clear evidence as to which specific treatment is most effective or whether combined treatment is more effective than individual treatment. The aim of this study was to determine the effectiveness of applying individual versus combined manual therapy techniques for patients with episodic TTH (ETTH) and chronic TTH (CTTH). Techniques included: suboccipital soft tissue inhibition, occiput-atlas-axis manipulation and the combination Figure 1. Participant flow and retention. Effect of MANUAL therapy on HEADACHE of both treatments. Patients were evaluated on different aspects of disability related to their headaches including headache frequency and severity. In addition, other headache-related factors were evaluated including photophobia, phonophobia and pericranial tenderness. Study population Materials and methods Eighty-seven patients were enrolled and 11 excluded (Figure 1) as they did not meet the inclusion criteria. Thus 76 (62 women) patients (age: 39.9±10.9 years) completed the study. The study involved a non-probability and convenience sampling from January to November 2012. Patients were recruited from different neurology clinics, and treatments were carried out in a specialized center for headache treatment. The sample consisted of patients diagnosed with either episodic TTH (ETTH) or chronic TTH (CTTH) with the headache characteristics established by the International Headache Society (IHS). 6, 7 Inclusion criteria were: aged between 18 and 65 years, headaches with over three months 642 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE December 2014
Effect of manual therapy on HEADACHE evolution, headache episodes lasting from 30 minutes to 7 days, meeting two or more of the characteristics of: bilateral location of pain, pressing nonpulsatile pain, mild to moderate pain or headaches not aggravated by physical activity. The headache could be associated with pericranial tenderness and patients should be under pharmacological control. Subjects with other types of headache were excluded from the study, as well as those with infrequent ETTH or probable TTH, and those who complained of vomiting during headache episodes. This study was approved by the ethical committee of the University of Valencia where the study was conducted. Informed consent of patients was obtained before treatment, and all procedures were conducted according to the Declaration of Helsinki. Study design The study was a factorial, randomized, controlled clinical trial. Treatment was performed by two therapists each with more than 10 years of experience in manual therapy. They were trained at applying the specific treatment by another researcher (specialist manual therapist) before starting the study and were unaware of the study and its objectives. The nature of the intervention (intervention delivered by a therapist versus no intervention) precluded blinding of treaters. Patients were randomly divided into three treatment groups and one control group (19 subjects per group). The first group received suboccipital soft tissue inhibition (SI); the second group received occiput-atlas-axis (OAA) manipulative treatment; the third received a treatment consisting of a combination of SI and OAA; and the forth group was the control group treated with no intervention. According to the nquery Advisor program, the required number for an ANOVA with one inter-subject factor was 19 subjects in each group, with four groups, assuming a 5% significance level for a large effect. After the initial clinical interview, patients were allocated to control or treatment groups using a computer generated randomization sequence, conducted and controlled by an assistant. Both the patients and assessors were unaware of the objectives of the study. The confidentiality of study material was in accordance with Spanish legislation on personal data protection (Act 15-1999 of 18 December). Assessment was carried out in two stages: at the beginning and end of treatment (at 4 weeks), and all patients in all groups were assessed under the same conditions before and after treatment by a blinded examiner. Intervention The treatment was composed of four sessions at 7-day intervals for all groups. At the initial session, with the patients lying supine, the vertebral artery occlusion test was applied bilaterally for all groups including patients assigned to the control group. Although there is controversy about its effectiveness for ensuring the absence of vascular injury, 8, 9 we deemed it appropriate prior to commencing the interventions. In addition, patients with symptoms that could refer vertebrobasilar insufficiency were excluded. Subsequently, with the patient positioned in supine, a specific treatment was applied depending on the group allocation and then the patients remained in a resting position in supine with a neutral head and neck position. This position was maintained after treatment for 5 minutes in the treatment groups and for a total of 10 minutes in the control group (substituting treatment time). Suboccipital soft tissue inhibition (SI) treatment The therapist placed his or her hands under the patient s head and made contact with the suboccipital musculature in the region of the posterior arch of the atlas, where pressure was progressively and deeply applied. This pressure was maintained for 10 minutes in order to produce the therapeutic effect of inhibition. The aim of this technique was to prevent suboccipital muscle spasms and suboccipital soft tissue spasms in general, which may lead to occipital, atlas and axis mobility dysfunction. 10 Manipulative treatment of the occiput, atlas and axis (OAA) Manipulation was performed on a vertical axis passing through the odontoid process of the axis; without flexion or extension, and very little lateral flexion. It was applied in two stages: firstly, a slight cephalic decompression was performed, then small circumductions were performed prior to manipulation; the joint barrier is located through selective Vol. 50 - No. 6 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE 643
pressure and subsequently a rotation toward the side to be manipulated is performed with a cranial helical movement. This technique was applied bilaterally, with the aim of restoring mobility of the joints between the occiput, atlas and axis. 11 Combined treatment (SI + OAA) Patients received the SI for 10 minutes followed by the OAA. Control intervention. No treatment technique was applied to the control group, however patients attended the same sessions and the same assessments were carried out. In each session, patients rested in supine for 10 minutes. Outcome measures The Headache Disability Inventory (HDI) 12, 13 was used to quantify the impact of headache-induced disability on daily life. The test-retest reliability of the total score of this questionnaire has been shown to be satisfactory (Pearson r 0.76 for 1 week; r=0.83 for 6 weeks). The purpose of this assessment tool is to identify the difficulties the patient may experience due to headaches. The questionnaire begins with two items that assess pain severity (mild, moderate, and severe) and frequency (once a month, from 1 to 4 times a month, and more than once a week). It also includes 25 questions on a functional subscale (12 items) and emotional subscale (13 items) with three possible response options (No=0 points; Sometimes=2 points; Yes=4 points). The maximum score is 100 points, ranging from 0=no disability to 100=severe disability. A decrease in the overall HDI of 16 points is considered to be a clinically significant improvement. 13 Considering that the presence of associated factors (photophobia or phonophobia and pericraneal tenderness) is an important feature of patients with TTH, 14 patients were also asked how many days that they presented with these symptoms over the last week. Statistical analysis Descriptive analyses for the overall sample and for each group were conducted, taking into account absolute and relative frequencies, as well Effect of MANUAL therapy on HEADACHE as correlations between the study variables, mean scores, standard deviation and confidence interval. An ANOVA confirmed the homogeneity of the groups before treatment, including the calculation and interpretation of the effect size index and the Levene statistic to verify compliance of the variance homogeneity assumption. In cases where it was significant, Brown-Forsythe Welch robust F-tests were conducted. The Student s t-test for related samples was used to compare the mean of the pre-test and post-test for each group, and subsequently, the calculation and interpretation of the effect size index was performed. The Kolmogorov-Smirnov test was used separately for each group and for each measurement, in order to verify compliance with normality. When not met, the differences were assessed by the Wilcoxon test. In order to examine between group differences, the amount of change of each variable (pre-test minus post-test value) was determined and the Kuskal-Wallis test was applied. The significance level established for all analyses was 0.05. Results A total of 40.8% of the patients suffered from CTTH, and 59.2%, frequent ETTH. Scores on the HDI recorded both pre and post treatment are presented in Table I. Headache frequency was significantly reduced for the group receiving either OAA or the combined therapies (both P<0.05). No change in headache frequency was observed for the SI group or the control group. However, headache severity was significantly reduced in all three treatment groups (all P<0.05). No change in headache severity was noted for the control group. Regarding the overall HDI score (functional and emotional subscale), the OAA and combined treatment group showed significant differences (P<0.05) with the same effect size (0.57). Although all treatment groups observed a significant improvement in the functional subscale of the HDI, the greatest effect size was noted for the combined treatment. Furthermore, the OAA and combined treatment resulted in significantly lower values of the emotional subscale of the HDI. The control group also showed a small but significant decrease in the emotional subscale score however the effect size was minimal (0.20). The group that received the combined treatment, 644 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE December 2014
Effect of manual therapy on HEADACHE photophobia (χ 2 (3)=4.196, P=0.24) and pericraneal tenderness (χ 2 (3)=3.570, P=0.31). For the overall HDI score, the group that received the combined intervention had a larger change than the group that received the SI intervention (P<0.05) and the control group (P<0.05), and the OAA intervention group had a larger change than the control group (P<0.05). For the functional subscale of the HDI, the OAA group had a larger change compared to the SI group (P<0.05) and control group (P<0.01) and the combined intervention had a larger change than the SI intervention (P<0.01) and control group (P<0.01). For headache severity, the OAA interreported significantly less frequency of pericranial tenderness and photophobia or phonophobia, with no improvement in the other groups. The results of the differences and effect size are also presented in Table I. Between group differences in the change in scores were also examined. Between group differences were significant for headache severity (χ 2 (3)=9.393, P<0.05), the functional subscale of the HDI (χ 2 (3)=16.710, P<0.01) and overall HDI score (χ 2 (3)=11.569, P<0.01), but not for the other variables: headache frequency (χ 2 (3)=4.543, P=0.20), emotional subscale of the HDI (χ 2 (3)=4.528, P=0.21), Table I. Mean±SD of scores from the HDI pre and post treatment for each group and mean and SD of the average days per week that the patient complained of pericranial tenderness, photophopia or phonophobia. SI Vol. 50 - No. 6 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE 645 OAA Combination Frequency HDI Pre-treatment 2.63 (0.59) 2.42 (0.60) 2.58 (0.50) 2.63 (0.59) Post-treatment 2.47 (0.61) 2.05 (0.70) 2.32 (0.47) 2.63 (0.59) Pre- post-treatment; p value z=-0.90;0.36 z=-2.11;0.03* z=-2.23;0.02* z=0.00;1.00 Size of effect 0.26 0.59 0.50 0 Severity HDI Pre-treatment 2.26 (0.65) 2.37 (0.68) 2.16 (0.50) 2.05 (0.70) Post-treatment 2.05 (0.78) 1.63 (0.76) 1.74 (0.65) 2 (0.81) Pre-Post-treatment; p value z=-2.00;0.04* z=-2.88;0.004* z=-2.53;0.01* z=-0.27;0.78 Size of effect 0.31 1.04 0.80 0.07 Overall HDI Pre-treatment 48.00 (23.45) 44.42 (22.71) 52.94 (24.35) 41.47 (25.55) Post-treatment 43.57 (22.62) 30.94 (21.25) 38.52 (27.07) 37.78 (23.68) Pre- post-treatment; p value T=1.72; 0.10 T=4.52; 0.000* T=4.93; 0.000* T=1.31; 0.20 Size of effect 0.18 0.57 0.57 0.14 Functional HDI Pre-treatment 26.53 (11.94) 22.84 (11.91) 29.37 (12.70) 21.89 (12.10) Post-treatment 23.58 (11.42) 15.05 (10.29) 19.89 (13.37) 21.26 (11.33) Pre- post-treatment; p value t=2.28;0.03* t=4.59;0.000* t=6.42;0.000* z=-0.19;0.84 Size of effect 0.24 0.63 0.71 0.05 Emotional HDI Pre-treatment 21.47 (12.68) 21.58 (12.01) 23.58 (12.30) 19.58 (14.66) Post-treatment 20.00 (11.83) 15.89 (11.38) 18.63 (14.42) 16.53 (12.80) Pre- post-treatment; p value t=0.93;0.36 t=3.47;0.003* t=2.47;0.02* z=-2.11;0.03* Size of effect 0.11 0.45 0.38 0.20 Photophobia or phonophobia Pre-treatment 0.79 (1,61) 0.21 (0,54) 1.00 (1,37) 0.80 (1,60) Post-treatment 0.47 (1,02) 0.11 (0,32) 0.47 (1,22) 0.50 (1,00) Pre- post-treatment; p value z=-0.85; 0.39 z=-1.00; 0.38 z=-2.05; 0.04* z=-0.86; 0.41 Size of effect 0.19 0.18 0.37 0.20 Pericranial tenderness Pre-treatment 0.84 (1.42) 0.68 (1.79) 1.26 (1.96) 0.74 (1.48) Post-treatment 0.37 (1.16) 0.63 (1.73) 0.32 (0.67) 0.68 (1.45) Pre- post-treatment; p value z=-1.41; 0.16 z=-0.38; 0.70 z=-2.25; 0.02* z=-0.14; 0.89 Size of effect 0.31 0.03 0.46 0.04 Z=Wilcoxon; t=student s t test; * P 0.05 Control n 19
vention group showed a larger change compared to SI intervention (P<0.05), and the control group (P<0.05). The mean ranks are presented in Table II. Discussion Effect of MANUAL therapy on HEADACHE Table II. s of differences (pre minus post treatment) for each variable and group. Values in bold demonstrated significance between group differences. SI Both OAA and SI as well as a combination of both applications reduced different aspects of headache disability in patients with TTH. OAA showed the greatest effect (effect size) for reducing both headache frequency and severity. However the combined intervention showed significantly greater improvements in the overall HDI compared to both SI and control interventions. Furthermore, additional measures of photophobia, photophobia and pericranial tenderness only improved in the group that received the combined treatment suggesting that combined treatment is the most appropriate for symptomatic relief of TTH. Previous studies 4, 15, 16 have shown that cervical manipulation is effective in the treatment of TTH reducing the frequency, duration and intensity of pain. For example, a combination of cervical and thoracic spine mobilization, and postural correction exercises were applied in patients with TTH for 8 weeks, including nine 30-minute sessions. Post treatment significant differences in favor of the treatment group were observed, both in the frequency (6.4 days; CI 95%: 8.3 to 4.6) and intensity (1.8, CI 95%: 3.1 to 0.7) of headache. These findings were supported by another study showing that the application of manipulation in patients diagnosed with TTH is effective at relieving headache intensity when tested in a double-blind, randomized study. 14 The results of our study confirm that manipulative techniques are effective for reducing overall headache disability and OAA Combination Control Differences frequency HDI 39.16 43.11 40.34 31.39 Differences severity HDI 34.16 47.63 41.82 30.39 Differences overall HDI 30.79 45.32 48.68 29.21 Differences functional HDI 30.39 45.89 51.18 26.53 Differences emotional HDI 32.53 43.18 44.45 33.84 Differences photophobia 37.68 33.58 36.97 45.76 Differences pericraneal tenderness 42.00 38.00 41.92 32.08 that positive effects can be observed after as little as 4 weeks of treatment. The application of soft tissue techniques has been shown to influence cervical muscle relaxation by decreasing the frequency and intensity of pain. 17, 18 Furthermore, soft tissue treatment combined with spinal manipulation has been shown to result in significant reductions in headache intensity and analgesic intake. 19 In the present study, the soft tissue treatment alone had a positive effect on headache severity and the functional subscale of the HDI however it was not superior to any of the other interventions including the control intervention in the between group analysis. Compared to the soft tissue treatment alone, a greater effect was observed when the soft tissue technique was combined with segmental manipulation. The SI technique was applied in this study with the aim of reducing the suboccipital muscle tension related to TTH. 17 Compared to the other treatments assessed, very little effect was obtained with the use of this technique, proving the treatment to be less effective than the others. This could be due to the fact that the technique chosen for the soft tissue was not the most suitable or that in applying the technique there was no active movement. Since there is no tissue displacement the effect may be less noticeable. However this study did not take into account other factors such as the presence of myofascial trigger points, which may have been influenced by the soft tissue treatment technique. Overall, when considering the effect on disability and additional symptoms of photophobia, photophobia and pericranial tenderness, the best outcome occurred for the group receiving the combined treatment approach. This observation confirms that multimodal management is the most effective for the 646 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE December 2014
Effect of manual therapy on HEADACHE management of headache. 20 The possible mechanisms for effect of both manipulation and SI treatment could be due to interaction between biomechanical factors and neurophysiological responses which likely induce movement restoration and pain sensitivity changes. 21, 22 Methodological considerations A strength of this study is that it was a randomized, controlled clinical trial investigating both individual therapies as well as a combined therapy. However, it must be noted that there are limitations. Evaluation of the duration of the positive effects in the medium and long-term requires further investigation. Furthermore, the effect of treatment on physical measures was not assessed. Concomitant medication treatment was also not controlled. Conclusions Manual therapy techniques are effective at improving different parameters related to symptoms and impact of TTH; however, the effectiveness for individual therapies have different effects. SI treatment alone is effective for reducing disability in two dimensions, namely function and headache severity however this treatment was not superior to any other treatment, including a control group. Manipulative OAA treatment alone is effective for reducing disability in terms of the headache severity, frequency, functional and emotional aspects related to the condition. However, when the two treatments were combined, effectiveness was noted for all aspects of disability, and other symptoms including photophobia, phonophobia and pericranial tenderness. angolarra JC, Barriga FJ, Pareja JA. Are manual therapies effective in reducing pain from tension-type headache? Clin J Pain 2006;22:278-85. 5. Crawford CC, Huynh MT, Kepple A, Jonas WB. Systematic assessment of the quality of research studies of conventional and alternative treatment(s) of primary headache. Pain Physician 2009;12:461-70. 6. The International Headache Society. The International Classification of Headache Disorders, 2nd edition. Cephalalgia 2004;24(Suppl 1):9-160. 7. Headache Classification Committee of the International Headache Society. New appendix criteria open for a broader concept of chronic migraine. Cephalalgia 2006;26:742-6. 8. Johnson EG, Landel R, Kusunose RS, Appel TD. Positive patient outcome after manual cervical spine management despite a positive vertebral artery test. Man Ther 2008;13:367-64. 9. Thiel H, Rix G. Is it time to stop functional pre-manipulation testing of the cervical spine?. Man Ther 2005;10:154-8. 10. Toro-Velasco C, Arroyo-Morales M, Fernández-de-las-Peñas C, Cleland JA, Barrero-Hernandez FJ. Short-term effects of manual therapy on heart rate variability, mood state, and pressure pain sensitivity in patients with chronic tension-type headache: a pilot study. J Manipulative Physiol Ther 2009;32:527-35. 11. Fryette HH. Occiput-Atlas-Axis. J Am Osteopath Assoc 1936;35:353-4. 12. Jacobson GP, Ramadan NM, Aggarwal SK. Newman CW. The Henry Ford Hospital Headache Disability Inventory (HDI). Neurology 1994;44:837-42. 13. Jacobson GP, Ramadan NM, Norris L, Newman CW. Headache Disability Inventory (HDI): short-term test-retest reliability and spouse perceptions. Headache 1995;35:534-9. 14. Espí-López GV, Oliva-Pascual-Vaca A. Atlanto-Occipital joint manipulation and suboccipital inhibition technique in the osteopathic treatment of patients with tension-type headache. Eur J Ost Clin Rel Res 2012;7:10-21. 15. Castien RF, van der Windt DA, Grooten A, Dekker J. Effectiveness of manual therapy for chronic tension-type headache: a pragmatic, randomised, clinical trial. Cephalalgia 2011;31:133-43. 16. Castien R, van der Windt D, Blankenstein AH, Heymans MW, Dekker J. Clinical variables associated with recovery in patients with chronic tension-type headache after treatment with manual therapy. Pain 2012;153:893-9. 17. Fernández-de-las-Peñas C, Alonso-Blanco C, Cuadrado ML, Gerwin RD, Pareja JA. Trigger points in the suboccipital muscles and forward head posture in tension-type headache. Headache 2006;46:454-60. 18. Moraska A, Chandler C. Pilot study of chronic tension type headache. J Man Manip Ther 2008;16:106-12. 19. Bove G, Nilsson N. Spinal manipulation in the treatment of episodic tensión-type headache. A Randomized Controlled Trial. JAMA 1998;280:1576-9. 20. van Ettekoven H, Lucas C. Efficacy of physiotherapy including a craniocervical training programme for tension-type headache; a randomized clinical trial. Cephalalgia 2006;26:983-91. 21. Bialosky JE, Bishop MD, Price DD, Robinson ME, George SZ. The mechanisms of manual therapy in the treatment of musculoskeletal pain: a comprehensive model. Man Ther 2009;14:531-8. 22. Bialosky JE, Simon CB, Mark D. Bishop MD, George SZ. Basis for spinal manipulative therapy: A physical therapist perspective. J Electromyogr Kinesiol 2012;22:643-7. 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