Do manual therapies have a specific autonomic effect? An overview of systematic reviews

Reported biological effects following Osteopathic Manipulative Treatment: A comprehensive mapping review

BACKGROUND AND PURPOSE

Osteopathic Manipulative Treatment (OMT) is a therapeutic whole-body approach mainly focused on correcting somatic dysfunctions. The aim of this scoping review is to systematically map the literature regarding the documented biological effects observed following OMT.

METHODS

The 2020 JBIRM version and the PRISMA-ScR were followed for the conceptualization and reporting of this review. The protocol was registered on the "Open Science Framework Registry" (https://doi.org/10.17605/OSF.IO/MFAUP). We searched for original articles published on Medline, Embase, and Scopus, from inception to the present.

RESULTS

Overall, 10,419 records were identified. After duplicate removal, screening for title and abstract, and specific exclusions with reasons, a total of 146 studies were included. Wide differences were detected among studies in their geographical localization, study design, temporal distribution, participants' condition, OMT protocols, and documented biological effects. Such variety in frequency distribution was properly described through descriptive statistics.

CONCLUSIONS

Biological modifications that appear to be induced by OMT have been detected in several body systems, but mostly in neurophysiological correlates and musculoskeletal changes. Results suggest a growing interest over the years on this topic, especially in the last two decades. More efforts in research are recommended to highlight whether such changes specifically depend on OMT, and to demonstrate its specific contribution to clinical practice.

Effect of manual osteopathic techniques on the autonomic nervous system, respiratory system function and head-cervical-shoulder complex-a systematic review

Background

Osteopathic manual techniques are now widely used in medicine worldwide. At present, there are no clear conclusions regarding the possibility of affecting the function of the autonomic nervous system (ANS), respiratory system and head-cervical-shoulder complex by manual osteopathic techniques.

Objectives

The aim of the study was to review the current literature regarding the possible impact of osteopathic manual techniques on the state of the autonomic nervous system, spirometric parameters of the respiratory system and the state of the head-collar-shoulder complex.

Methods

Publications have been searched in the following databases: PubMed, Virtual Health Library and Cochrane Central Register of Controlled Trials. The search strategy included keywords related to manual osteopathic treatment, autonomic nervous system, spirometry, respiratory function and head, neck and shoulder pain. The methodological quality of the included studies was assessed. The PRISMA guidelines were used for the systematic review. Studies from 2010 to 2023 were selected.

Results

Using the proposed descriptions and manual searches from the literature of other works, 40 studies were found, out of which 22 were rejected because they did not meet the inclusion criteria. The analysis included: 15 randomized controlled trials, 3 pilot studies.

Conclusion

Studies clearly show the effect of OMT on both spirometric parameters and the condition of the head-collar-shoulder complex. Most often this translates into improved ANS performance, but there are exceptions.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, CRD42023476963.

Association between myofascial trigger point therapy and conditioned pain modulation

INTRODUCTION

Myofascial trigger point therapy (MTrP) is a widely used therapeutic approach, although the underlying mechanisms remain unclear. Mechanisms discussed include peripheral involvement of muscles as well as central pain modulating processes such as the conditioned pain modulation (CPM). The aim of this study was to investigate whether the analgesic response of MTrP and the analgesic response of CPM correlate in asymptomatic participants in order to identify shared underlying mechanisms of MTrP and CPM.

METHOD

Both, CPM and MTrP protocols consisted of heat-based test stimuli (heat pain thresholds before and after the intervention) and pressure-based (conditioning) stimuli. Asymptomatic participants (n = 94) were randomly assigned to receive either mild, intense or no pressure stimuli (between-group design) to both the fingernail and the MTrP of the infraspinatus muscle (within-group design). Pressure stimuli at both locations (fingernail, MTrP) were applied with a pressure algometer for 120 s and continuously adjusted to maintain a constant pain intensity of mild or intense pain. All thermal stimuli were applied on the lower leg with a thermal stimulator.

RESULTS

A significant correlation was shown between the analgesic effect of CPM and MTrP therapy for mild (r = 0.53, p = 0.002) and intensive stimuli (r = 0.73, p < 0.001). 17.3% of the variance of the MTrP effect were explained by CPM after mild stimulation, and 47.1% after intense stimulation. Pain-related characteristics did not explain the variance within the analgesic response using a regression analysis.

CONCLUSIONS

Between the analgesic responses following MTrP and CPM paradigms, a moderate to strong correlation was observed, suggesting shared underlying mechanisms.

Vertebral Subluxation and Systems Biology: An Integrative Review Exploring the Salutogenic Influence of Chiropractic Care on the Neuroendocrine-Immune System

In this paper we synthesize an expansive body of literature examining the multifaceted influence of chiropractic care on processes within and modulators of the neuroendocrine-immune (NEI) system, for the purpose of generating an inductive hypothesis regarding the potential impacts of chiropractic care on integrated physiology. Taking a broad, interdisciplinary, and integrative view of two decades of research-documented outcomes of chiropractic care, inclusive of reports ranging from systematic and meta-analysis and randomized and observational trials to case and cohort studies, this review encapsulates a rigorous analysis of research and suggests the appropriateness of a more integrative perspective on the impact of chiropractic care on systemic physiology. A novel perspective on the salutogenic, health-promoting effects of chiropractic adjustment is presented, focused on the improvement of physical indicators of well-being and adaptability such as blood pressure, heart rate variability, and sleep, potential benefits that may be facilitated through multiple neurologically mediated pathways. Our findings support the biological plausibility of complex benefits from chiropractic intervention that is not limited to simple neuromusculoskeletal outcomes and open new avenues for future research, specifically the exploration and mapping of the precise neural pathways and networks influenced by chiropractic adjustment.

Effectiveness of spinal manipulation in influencing the autonomic nervous system - a systematic review and meta-analysis

BACKGROUND

Spinal manipulation (SM) has been hypothesized to influence the autonomic nervous system (ANS). Further, it has been proposed that the effects may vary depending on the segment manipulated. The aim of this systematic review was to synthesize the current level of evidence for SM in influencing the ANS in healthy and/or symptomatic population.

METHODS

Various databases (n = 8) were searched (inception till May 2023) and 14 trials (n = 618 participants) were included in the review. Two authors independently screened, extracted and assessed the risk of bias in included studies. The data were synthesized using standard mean differences and meta-analysis for the primary outcome measures. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was used for assessing the quality of the body of evidence for each outcome of interest.

RESULTS

Overall, there was low quality evidence that SM did not influence any measure of ANS including heart rate variability (HRV), oxy-hemoglobin, blood pressure, epinephrine and nor-epinephrine. However, there was low quality evidence that cervical spine manipulation may influence high frequency parameter of HRV, indicating its influence on the parasympathetic nervous system.

CONCLUSION

When compared with control or sham interventions, SM did not alter the ANS. Due to invalid methodologies and the low quality of included studies, findings must be interpreted with great caution. Future studies are needed which employ rigorous data collection processes to verify the true physiological implications of SM on ANS.

Does Osteopathic Heart-Focused Palpation Modify Heart Rate Variability in Stressed Participants with Musculoskeletal Pain? A Randomised Controlled Pilot Study

Heart rate variability (HRV) describes fluctuations in time intervals between heartbeats and reflects autonomic activity. HRV is reduced in stressed patients with musculoskeletal pain and improved after osteopathic manipulative treatment and mind-body interventions. Heart-focused palpation (HFP) combines manual and mind-body approaches to facilitate relaxation. This randomised controlled pilot study investigated the feasibility and sample size for a future randomised controlled trial and the effect of a single treatment with HFP or sham HFP (SHAM) on short-term HRV. A total of Thirty-three adults (47.7 ± 13.5 years old) with stress and musculoskeletal pain completed the trial with acceptable rates of recruitment (8.25 subjects per site/month), retention (100%), adherence (100%), and adverse events (0%). HFP (n = 18), but not SHAM (n = 15), significantly increased the root mean square of successive RR interval differences (p = 0.036), standard deviation of the NN intervals (p = 0.009), and ratio of the low-frequency to high-frequency power band (p = 0.026). HFP and SHAM significantly decreased the heart rate (p < 0.001, p = 0.009) but not the stress index and ratio of the Poincaré plot standard deviation along and perpendicular to the line of identity (p > 0.05). A power analysis calculated 72 participants. Taken together, the study was feasible and HFP improved HRV in stressed subjects with musculoskeletal pain, suggesting a parasympathetic effect.

The efficacy of manual therapy on HRV in those with long-standing neck pain: a systematic review

OBJECTIVES

Long-standing neck pain (LNP) is a clinical condition frequently encountered in the physical therapy clinic. LNP is a complex, multifactorial condition affecting multiple body systems including the autonomic nervous system (ANS). Traditionally, research on the impact of physical therapy on LNP has focused on self-report measures and pain scales. Heart rate variability (HRV) is an objective measure of the ANS, allowing for quantification of effects of treatment. This systematic review is intended to evaluate if manual therapy acutely affects heart rate variability in adults with long-standing neck pain.

METHODS

Pubmed, Medline, CINAHL, Google Scholar, Web of Science, and Cochrane library were used to retrieve the randomized controlled trials for this review between the years 2010-2021. Search terms included: chronic neck pain, neck pain, cervical pain, manual therapy, mobilization, manipulation, osteopathy, osteopathic or chiropractic. Heart rate variability, HRV, heart rate variation, effects, outcomes, benefits, impacts or effectiveness.

RESULTS

Of 139 articles located and screened, three full-text articles were selected for full qualitative synthesis, with a combined population of 112 subjects, 91 of which were female, with an average age of 33.7 ± 6.8 years for all subjects. MT techniques in three studies were statistically significant in improving HRV in people with LNP; however, techniques were differed across studies, while one study showed no benefit. The studies were found to be of high quality with PEDro scores ≥6.

CONCLUSIONS

Although no clear cause and effect relationship can be established between improvement in HRV with manual therapy, results supported the use of MT for an acute reduction in HRV. No one particular method of MT has proven superior, MT has been found to produce a statistically significant change in HRV. These HRV changes are consistent with decreased sympathetic tone and subjective pain.

Modulation of Heart Rate Variability following PAP Ion Magnetic Induction Intervention in Subjects with Chronic Musculoskeletal Pain: A Pilot Randomized Controlled Study

Heart rate variability (HRV) analysis has emerged as a simple and non-invasive technique to indirectly evaluate the autonomic nervous system (ANS), and it is considered a sensible and advanced index of health status. Pulsed electromagnetic fields (PEMFs) are widely used in clinical settings for improving the health status of individuals with chronic musculoskeletal pain. The aim of the present single-blind, randomized, placebo-controlled parallel pilot study was to investigate the acute effect of a single session of PEMFs stimulation by a PAP ion magnetic induction (PAPIMI) device on ANS activity, as measured by HRV, in patients with chronic musculoskeletal pain, and compare such effect with that induced by a sham (control) PAPIMI inductor. Thirty-two patients were randomized into two groups: PAPIMI intervention (PAP) (n = 17) and sham PAPIMI intervention (SHAM-PAP) (n = 15). HRV was assessed before and following the interventions. The PAP group showed a significant increase in all values of the time-domain parameters (SDNN, RMSSD, NN50, and pNN50) and the HF component of HRV, suggesting a parasympathetic effect. In contrast, the SHAM-PAP group showed no significant differences in all HRV indices following the intervention. Preliminary findings suggested that PAPIMI inductor could influence ANS activity and provided initial evidence of the potential physiological response induced by the PAPIMI device.

Evidence (-based medicine) in manual medicine/manual therapy—a summary review

Objective

The aim of this summary review is to analyse the current state of evidence in manual medicine or manual therapy.

Methods

The literature search focussed on systematic reviews listed in PubMed referring to manual medicine treatment until the beginning of 2022, limited to publications in English or German. The search concentrates on (1) manipulation, (2) mobilization, (3) functional/musculoskeletal and (4) fascia. The CASP Checklist for Systematic Reviews was used to present the included reviews in a clear way.

Results

A total of 67 publications were included and herewith five categories: low back pain, neck pain, extremities, temporomandibular disorders and additional effects. The results were grouped in accordance with study questions.

Conclusion

Based on the current systematic reviews, a general evidence-based medicine level III is available, with individual studies reaching level II or Ib. This allows manual medicine treatment or manual therapy to be used in a valid manner.

Are changes in pain associated with changes in heart rate variability in patients treated for recurrent or persistent neck pain?

BACKGROUND

Persistent or recurrent neck pain is associated with perturbations in the autonomic nervous system balance, and nociceptive stimulation has been seen to influence this balance. However, very few prospective studies have addressed the extent to which changes in pain associate with changes in autonomic cardiac regulation. Therefore, we investigated if changes in pain vary with changes in heart rate variability in a cohort of patients treated for persistent or recurrent neck pain.

METHOD

This analysis is based on data from a randomized controlled trial in which participants were given home stretching exercises with or without spinal manipulative therapy for two weeks. As the effectiveness of the intervention (home stretching exercises and spinal manipulative therapy) was found to be equal to the control (home stretching exercises alone), all 127 participants were studied as one cohort in this analysis. During the intervention, pain levels were recorded using daily text messages, and heart rate variability was measured in the clinics three times over two weeks. Two approaches were used to classify patients based on changes in pain intensity: 1) Clinically important changes in pain were categorized as either "improved" or "not improved" and, 2) Pain development was measured using pain trajectories, constructed in a data driven approach. The association of pain categories and trajectories with changes in heart rate variability indices over time were then analysed using linear mixed models.

RESULTS

Heart rate variability did not differ significantly between improved and not-improved patients, nor were there any associations with the different pain trajectories.

CONCLUSIONS

In conclusion, changes in pain after home stretching exercises with or without spinal manipulative therapy over two weeks were not significantly associated with changes in heart rate variability for patients with persistent or recurrent neck pain. Future studies should rely on more frequent measurements of HRV during longer treatment periods.

TRIAL REGISTRATION

The trial was registered at ClinicalTrials.gov, registration number: NCT03576846.

Efficacy and Feasibility of an Osteopathic Intervention for Neurocognitive and Behavioral Symptoms Usually Associated With Fetal Alcohol Spectrum Disorder

The purpose of this study was to evaluate the efficacy and feasibility of a 4-week planned osteopathic manipulative treatment intervention on the improvement of neurocognitive and behavioral symptoms usually associated with fetal alcohol spectrum disorder. Thirty-two symptomatic children without fetal alcohol spectrum disorder aged 3-6 years with low level of attention from two schools and an osteopathic center were recruited in a prospective randomized pilot study in an osteopathic manipulative treatment group [osteopathic manipulative treatment (OMT)] or a control group (standard support measures). Neurocognitive maturity test results for attention (A), iconic memory (IM), spatial structuration (SS), and visual perception (VP) were recorded at baseline and post-intervention. No adverse effects were communicated and there were no dropouts. A significant increase in neurocognitive assessments was observed in children in the OMT group at post-treatment. Intergroup post-intervention statistical differences were found for A, SS, and IM were p = 0.005, p < 0.001, and p < 0.001, respectively; no differences were seen for VP (p = 0.097). This study shows that a 4-week osteopathic manipulative treatment intervention may be a feasible and effective therapeutic approach for neurocognitive and behavioral symptoms usually present in fetal alcohol spectrum disorder, justifying more studies on children affected by this condition.