Craniosacral Therapy for the Treatment of Chronic Neck Pain: A Randomized Sham-controlled Trial.

OBJECTIVES: With growing evidence for the effectiveness of craniosacral therapy (CST) for pain management, the efficacy of CST remains unclear. This study therefore aimed at investigating CST in comparison with sham treatment in chronic nonspecific neck pain patients.
MATERIALS AND METHODS: A total of 54 blinded patients were randomized into either 8 weekly units of CST or light-touch sham treatment. Outcomes were assessed before and after treatment (week 8) and again 3 months later (week 20). The primary outcome was the pain intensity on a visual analog scale at week 8; secondary outcomes included pain on movement, pressure pain sensitivity, functional disability, health-related quality of life, well-being, anxiety, depression, stress perception, pain acceptance, body awareness, patients' global impression of improvement, and safety.
RESULTS: In comparison with sham, CST patients reported significant and clinically relevant effects on pain intensity at week 8 (-21 mm group difference; 95% confidence interval, -32.6 to -9.4; P=0.001; d=1.02) and at week 20 (-16.8 mm group difference; 95% confidence interval, -27.5 to -6.1; P=0.003; d=0.88). Minimal clinically important differences in pain intensity at week 20 were reported by 78% within the CST group, whereas 48% even had substantial clinical benefit. Significant between-group differences at week 20 were also found for pain on movement, functional disability, physical quality of life, anxiety and patients' global improvement. Pressure pain sensitivity and body awareness were significantly improved only at week 8. No serious adverse events were reported. DISCUSSION: CST was both specifically effective and safe in reducing neck pain intensity and may improve functional disability and the quality of life up to 3 months after intervention.

RCT Entities:   Population Interventions Outcomes

Neck pain is a significant public health problem with 1 in 2 people experiencing neck pain at least once in their lifetime.1 Neck pain is often recurrent, of nonspecific nature, and associated with disability in both social and occupational life.2–4 For the treatment of chronic courses, evidence is still limited, as only therapeutic exercises, acupuncture, and manual therapies were recommended in recent clinical practice guidelines.5–7 On asking manual therapists about their perception and use of complementary and alternative medicine for the treatment of chronic pain conditions, one repeatedly mentioned treatment was craniosacral therapy (CST).8

CST is thought to be a noninvasive, mindfulness-based treatment approach using gentle manual palpation techniques to release fascial restrictions between the cranium and the sacrum.9 The craniosacral system anatomically encompasses the structures of the central nervous system including the skull, the cranial sutures, the cerebrospinal fluid, and the membranes of the brain and the spinal cord. It is influenced by and linked to the musculoskeletal system,10 and presumably to the vascular and endocrine system as well as to the sympathetic and parasympathetic nervous system.11 In the craniosacral theory, fascial restrictions within the craniosacral system lead to abnormal, arrhythmic motion of the cerebrospinal fluid. This craniosacral rhythm is assessable by palpation and quantifiable by encephalogram, myelogram, and magnetic resonance imaging.12 There is also growing evidence for fascial involvement in pain chronification. Studies have shown increased activity of fascial nociceptors within restricted connective tissue, which can contribute to remodeling processes of inflammation and fibrosis, increased tissue stiffness, muscle tension, and chronic pain.13,14 However, research on craniosacral diagnostic and treatment mechanisms revealed very heterogenous results,11,12 with only preliminary evidence supporting inherent processes of peripheral and descending pain inhibition due to gentle fascial palpation techniques.11,15,16

The effectiveness of craniosacral treatment on health outcomes has been shown for a number of chronic pain syndromes, but it is limited to observational designs and randomized controlled trials with low to moderate methodological quality.17–19 Efficacy studies and studies on musculoskeletal pain have not been conducted to date,20 although neck and back pain were the most frequent symptoms for which CST was requested.21 Therefore, this study aimed at investigating the efficacy of CST in chronic nonspecific neck pain in comparison with a manual sham control intervention.

MATERIALS AND METHODS

Trial Design and Registration

The study was designed as a randomized controlled clinical trial with a parallel-group design and 3 months of follow-up observation. After baseline assessment, patients were randomized into either the CST group or an active attention-control group receiving light-touch sham treatment. Outcome measures were collected at week 8 after randomization (after intervention) and week 20 after randomization (3-month follow-up). The trial was conducted between February 2012 and May 2013 at the Department of Internal and Integrative Medicine, Kliniken Essen-Mitte, University of Duisburg-Essen, Essen, Germany. Before patient recruitment, the trial protocol was approved by the ethics committee of the University of Duisburg-Essen, Germany (11-4850-BO), and registered at ClinicalTrials.gov (NCT01526447).

Randomization

A statistician who was not involved in conducting the study generated a nonstratified allocation sequence with randomly varying block lengths using the random number generator RANUNI from the SAS/STAT software (release 9.2, SAS Inc.). On the basis of these random number tables, he prepared sealed and opaque envelops sorted in the ascending order of randomization. To reveal patients’ group assignment, the envelop with the lowest number was opened directly after each baseline assessment by the trial coordinator who was involved neither in the random sequence generation nor in the assessment of study outcomes.

Sample Criteria

Patients were recruited from specialist care, primary care, and noncare populations through advertisements. To assess eligibility, those who called were screened by a research assistant, whereupon eligible patients obtained written study information and a physical and neurological examination by a study physician. If all eligibility criteria were met, patients had to give written inform consent and were included in the study.

Inclusion criteria were an age of 18 to 65 years, chronic nonspecific neck pain for 3 months or more with at least moderate pain intensity of ≥45 mm on a 100-mm visual analog scale (VAS),22 and treatment naivety with respect to CST. Participation was not possible in cases of specific neck pain due to degenerative diseases (disk prolapse, scoliosis), inflammatory diseases (spondylitis, arthritis), neurological diseases (neuropathy, multiple sclerosis), physical trauma (whiplash, operation at the cervical spine), or neoplasms of the spine. Severe comorbid somatic and psychiatric disorders such as oncological diseases or major depression and current pregnancy also were exclusion criteria. Patients taking corticosteroids, opiates, muscle relaxants, antidepressants, or those with recently initiated or modified drug therapy or invasive/manipulative treatment were also excluded.

The sample size was calculated on the basis of pain intensity ratings of chronic nonspecific neck pain patients who received osteopathic manipulative treatment23 using the G*Power software (release 3.1.3, Kiel University, Germany).24 To detect an expected group difference of 1.73±SD of 2.16 on a 10-point numeric rating scale (effect size of 0.84) with a power of 80%, a 2-sided t test with α=5% significance level required 24 patients per group. Accounting a possible loss of statistical power due to patient withdrawal of 10%, a total sample size of 54 patients was calculated.

Blinding

First, patients were blinded to the group allocation and to the fact that 1 group would receive sham treatment as it was recommended for manual therapy trials25; instead they were told that 2 different CST techniques would be tested. Second, investigators assessing outcomes remained blind to patients’ group allocation during the whole study period. Third, the statistician who conducted outcome analyses was blinded to the group allocation by renaming the groups with numbers.

Interventions

Standardized treatment protocols comprised 8 units of CST or sham treatment once a week lasting 45 minutes each. Patients of both groups received initial structural CST examination, which was repeated at the end of each unit, and was treated by 1 of 4 licensed physiotherapists with advanced CST qualification, and on average 6 years of clinical practice. Treatment steps were recorded by therapists using a structured log.

The Treatment Group

The CST protocol was designed to release restrictions of the cranium and the spine up to the pelvis and the sacrum using standardized application of gentle fascial traction, release, and unwinding techniques in accordance with the respective palpated restrictions.26,27 The techniques applied included frontal and parietal lift, medial compression of the parietal bones, release of the sagittal suture and the atlanto-occipital joint, compression-decompression of the sphenobasilar and the temporomandibular joints, cranial base release, release of the hyoid diaphragm and the thoracic inlet, dural tube traction, respiratory and pelvic diaphragm release, lumbosacral and sacroiliac decompression, fascial unwinding of the neck/shoulders and lower limbs, and still point induction.9,15 If indicated, dialog techniques for increasing body awareness and assisting the process of somato-emotional release were used.28

The Sham Control Group

The sham protocol was designed to be credible but not specifically effective. Therefore, light touch was applied on standardized anatomic areas, equal to those treated with CST, for 2 minutes each time.29,30 In addition, body awareness instructions were given to simulate CST dialog techniques.

Outcome Measures

The primary outcome was an average pain intensity during the last 7 days, recorded on a 100-mm VAS at week 8.31 Secondary outcomes were pain on movement, pressure pain sensitivity, neck pain-related disability, health-related quality of life, well-being, anxiety and depression, stress perception, pain acceptance, body awareness, patients’ global impression of improvement, and safety.

To assess pain on movement, patients obtained the Pain on Movement Questionnaire and were asked to rate the pain intensity on a 100-mm VAS while flexing, extending, laterally flexing, and laterally rotating their head. The average pain on movement score was then calculated from all movement directions.32 Pressure pain sensitivity was measured at the individual point of maximum pain and bilaterally at anatomically predefined sites (levator scapulae, trapezius, and the semispinalis capitis muscle). For these points, pressure pain thresholds were determined 3 times each using a digital algometer (Somedic AB, Hörby, Sweden) with a 1-cm2 cylinder. Pressure was applied in steps of 40 kPa/s until patients stated pain in addition to pressure.33,34 Functional disability was assessed using the Neck Disability Index, a 10-item questionnaire that enquired the disability in daily activities induced by neck pain. Scores of <9 indicate no perceived disability, 10 to 29 mild disability, 30 to 49 moderate disability, 50 to 69 severe disability, and 70 to 100 complete disability.35 Health-related quality of life was assessed on 2 subscales, physical and mental quality of life, using the 12-item Short Form Health Survey. Subscales were standardized to a mean of 50±SD of 10 and a range of 0 to 100, with 0 indicating the lowest level and 100 the highest level of health.36 Well-being was measured by the sum score of the 16-item Questionnaire for Assessing Subjective Physical Well-being (FEW-16).37 Anxiety and depression were measured using the Hospital Anxiety and Depression Scale. Each subscale is composed of 7 items with a maximum of 21 points. Scores below 8 indicated anxiety and depression levels within normal limits, 8 to 10 points indicated subclinical levels, and over 10 points a possible clinical disorder.38 To assess stress perception, patients obtained the Perceived Stress Questionnaire in the 20-item version.39 Pain acceptance was measured by the 8-item Positive Life Construction Scale of the Emotional/Rational Disease Acceptance Questionnaire.40 Body awareness was measured by the Scale of Body Connection, which is composed of 2 subscales: Body Awareness and Body Dissociation.41 Patients’ ratings of their Global Impression of Improvement (PGI-I) were assessed on a 7-point scale from 1 (very much improved) to 7 (very much worse).42,43 Safety assessment was realized by asking patients at the beginning of each treatment unit about the frequency and the severity of side effects. In addition, patients were requested to document side effects as well as concurrent treatment and medication use in a daily log.

Furthermore, treatment expectancy was assessed as part of the Credibility/Expectancy Questionnaire on a 9-point rating scale from 1 (not at all) to 9 (very much).44,45 Treatment credibility and quality of the therapeutic alliance, measured by the Helping Alliance Questionnaire,46 were analyzed and reported separately.47

Statistical Analysis

All analyses were based on the intention-to-treat population including all patients who were initially randomized, regardless of whether they had missing data or were not fully adhering to the treatment protocol. Missing at random values were imputed 20 times using fully conditional specification iterations, a multiple imputation technique based on multivariate regression models of baseline values and sociodemographic parameters.

Dropout analyses and baseline comparability were analyzed using independent-samples t tests for continuous data and χ2 tests for categorical data. Concurrent medication use was converted into defined daily doses (DDD)48 and analyzed using repeated measures analysis of covariance with the treatment group as the classified factor and patients’ expectations as the linear covariate. The primary outcome was analyzed as a function of the treatment group (classified factor), patients’ expectations, and respective baseline values (linear covariates) using univariate analysis of covariance. Between-group differences (Δ) and 95% confidence intervals (CI) were estimated using 2-sided t tests, and an alpha level of 5%. Equal models were applied for secondary outcomes, which were analyzed were exploratory. This way, no alpha-level adjustment for multiple testing was necessary.49 For each outcome, standardized effect sizes (Cohen’s d) were calculated by dividing estimated group differences by the pooled SD at baseline. In addition, responder analyses were calculated for patients who improved by at least 20% of their respective baseline values (minimal clinically important difference) and for patients with at least 50% improvement (substantial clinical benefit).50,51 Between-group differences for treatment response analyses were tested with χ2 tests. All analyses were performed using the SPSS software (release 22.0, IBM).

RESULTS

Patient Recruitment and Flow

Figure 1 displays the Consort flow chart of patient recruitment and loss during the study period. Out of 150 initially interested patients, 96 had to be excluded because of not fulfilling the eligibility criteria or for reporting scheduling problems. In total, 54 patients were randomized and allocated to 1 of the 2 treatment groups. Whereas 4 patients from the CST group and 8 patients from the sham group did not attend all treatment units provided, only 3 patients were lost to assessment at week 8. Reasons for dropout were scheduling problems and loss of interest. At week 20, dropout of 7 patients was recorded due to scheduling problems, whereas 2 others made no further reply. Comparisons of patients who completed the study with those who were lost to week 8 and week 20 revealed no significant differences concerning their social demographics, neck pain characteristics, and treatment expectancy (P≥0.05) (Table 1).

FIGURE 1

A consort flow chart of patient recruitment and loss. CST indicates craniosacral therapy.

TABLE 1

Dropout Analysis

Sample Characteristics at Baseline

Patients’ baseline characteristics are shown in Table 2. Their ages ranged from 19 to 65 years, with a mean of 44.6±10.0 years. All were whites. Most were female (81.5%), employed, and of normal body mass index. The sample included patients from all educational levels, which were equally distributed. Patients reported 9.6±8.9 years of neck pain duration, and most of them had received several pharmacological and nonpharmacological treatments during that time. No significant differences in patients’ social demographics and neck pain characteristics were found between study groups (P≥0.05). Patient’s expectations that CST would be successful in reducing their neck pain symptoms were also comparable between groups (P≥0.05).

TABLE 2

Sample Characteristics at Baseline

Concurrent Treatments

Patients’ use of concurrent pain medication is illustrated in Figure 2. During the 8 weeks of treatment, the average intake of analgesics was 0.1±0.1 DDD in the CST group and 0.5±0.3 DDD in the sham group. Analysis revealed no significant main effect of time (P=0.716) and group (P=0.099), and no significant time-group interaction (P=0.069). Other concurrent treatments were reported by 5 patients in the sham group who used massage 4 times and acupuncture 2 times.

FIGURE 2

Concurrent analgesics use (mean±SD) of craniosacral therapy (black) and sham patients (gray) during the active study period.

Primary Outcome

Effects on the primary outcome are shown in Table 3. In comparison with sham, patients in the CST group reported a significantly lesser pain intensity of Δ=−21.0 mm at week 8 (95% CI, −32.6 to −9.4; P=0.001; d=1.02) and ∆=−16.8 mm at week 20 (95% CI, −27.5 to −6.1; P=0.003; d=0.88).

TABLE 3

Effects (Mean±SD) of Craniosacral Therapy in Comparison With Sham

A minimal clinically important pain reduction of at least 20% was reported by 74.1% of the CST patients against 40.7% of the sham patients at week 8 (P=0.013), and 77.8% of the CST patients against 51.9% of the sham patients at week 20 (P=0.046). A substantial clinical benefit of at least 50% pain relief at week 8 was reported by 44.4% of the CST patients against 14.8% of the sham patients (P=0.017). At week 20, a comparison of 50% response rates did not reach the level of significance (P=0.091) (Table 4).

TABLE 4

Responder Analysis

Secondary Outcomes

Analyses of secondary outcomes are also shown in Table 3. At week 8, significant between-group differences were detected for pain on movement (P=0.001; d=0.92), pressure pain thresholds at the point of maximum pain (P=0.038; d=0.52), and bilaterally at the trapezius muscle (P=0.042; d=0.43), functional disability (P=0.010; d=0.73), physical quality of life (P=0.013; d=0.64), body awareness (P=0.001; d=0.59), and global improvement (P=0.000; d=1.01). At week 20, significant effects could be detected for pain on movement (P=0.020; d=0.66), functional disability (P=0.006; d=0.80), physical quality of life (P=0.000; d=1.07), and global improvement (P=0.029; d=0.62). Although anxiety and depression levels were reduced in the CST group and increased in the sham group, between-group comparisons were significant only for anxiety and only at week 20 (P=0.020; d=0.58). No significant group differences were found for stress perception, well-being, mental quality of life, pain acceptance, and body dissociation (P≥0.05).

Safety

No serious adverse events were reported. Minor adverse events during or subsequent to the treatment were reported by 6 patients in the CST group and included increased neck pain in 2 patients and pain in the jaw area, shivering, tiredness, strong emotional reactions, and weeping in 1 patient, respectively. Within the sham group, 8 patients reported minor side effects, which included transient headache or migraine in 7 patients, worsened neck pain in 3 patients, tingling sensations in 2 patients, and dizziness in 1 patient. In all reported cases, symptom worsening subsided shortly after the respective treatment unit. Another 2 patients, 1 from each group, discontinued study participation in consequence of recurrent headache during treatment, but were free of headaches at both follow-up assessments.

DISCUSSION

Summary of Evidence

The present study is the first randomized controlled trial that revealed efficacy for CST in comparison with manual sham treatment. In a patient sample with a mean duration of 9.6 years of nonspecific neck pain, significant and clinically relevant effects on the pain intensity were found directly after the active treatment period and at week 20, a further 3 months later. Minimal clinically important differences in pain intensity at week 20 were reported by almost 78% within the CST group, whereas 48% even had substantial clinical benefit. An exploratory analysis also revealed significant between-group differences at weeks 8 and 20 for pain on movement, functional disability, physical quality of life, and patients’ global impression of improvement. Pressure pain sensitivity and body awareness were significantly improved only directly after 8 weeks of treatment, and anxiety only at week 20. No serious adverse events were reported.

Results are in line with previous pain research in CST and recommended neck pain treatments. Although CST was shown to be effective in improving pain intensity, functional disability, and health-related quality of life in comparison with waiting list,52 relaxation,53,54 off-state physical devices,55,56 or standard medical care,57 this study found comparable effects in blinded patients with respect to sham. The effect sizes are comparable to those of neck pain guideline treatments58–61 and more than likely cannot be explained exclusively by nonspecific treatment effects, which were found to be only of small to medium effect sizes.62 Specific effects of the used CST techniques seem to be probable, given the broad nociceptive and low-threshold mechanosensory innervations of the fasciae,16,63 Treating fasciae has been shown to induce a decreased tone of intrafascial muscle cells, decreased muscles tension, and increased parasympathetic nervous system response and vagal tone, in vitro63 and in vivo.64 Pain relief, decreasing muscles tension, and the experience of deep relaxation and release were also reported by the interviewed patients treated with CST.65,66 Further described results of CST included the reduction of state and trait anxiety, whereas depression levels were often not influenced significantly.29,56 Adverse events have been reported only by 1 randomized controlled trial in detail, with temporarily increased symptoms and tiredness occurring most often.57 In the CST theory, such transient symptom aggravation, tiredness, and the described emotional release reactions are usually understood as positive vegetative responses to treatment,28 which were also reported in studies of osteopathy, massage therapy, and acupuncture.67–69

Strengths and Weaknesses

The strengths of the study design included the random and concealed allocation procedure, the intention-to-treat analysis, the active attention-control and touch-control condition, comparable concurrent treatments, and the successful blinding of patients47 and outcome assessors.

However, there are certain limitations. First of all, the sample size was relatively small and consisted of 81.5% of female patients, which may reduce the representativity and the generalizability of the results. Even so, the analyses conducted had adequate statistical power, suggesting comparable results even in bigger samples. Epidemiological surveys otherwise show a generally higher neck pain prevalence in women,1,3 which in turn would explain the greater percentage of included women compared with men. Second, the comparability of the CST and the sham groups may be limited due to the allocation to the therapists. Whereas 3 therapists performed CST, only 1 therapist performed the sham treatment. However, secondary analyses have shown that the alliance to the assigned therapists did not systematically affect study outcomes.47 Nonetheless, the treatment protocols used only allow for conclusions about the effect of CST on subjective clinical outcomes. It remains unclear whether CST techniques actually affect the indicated fascial structures and joints, and if so, whether these changes in turn would result in quantifiable physiological responses. The design therefore would have to include further objective physiological measures and an even more standardized application of fascial palpation techniques.

CONCLUSIONS

CST was shown to be specifically effective and safe in reducing neck pain intensity and may improve the functional disability and the quality of life up to 3 months after the intervention. Particularly in chronic and recurrent neck pain, CST may be a worthwhile treatment option in addition to standard medical care. Further studies with rigorous methodological designs and long-term follow ups are needed to confirm CST efficacy in neck pain treatment.