Systematic Reviews of Spinal Manipulations for Headaches: An Attempt to Clear Up the Confusion

The cervical spine in tension type headache

INTRODUCTION

The concept that headaches may originate in the cervical spine has been discussed over decades and is still a matter of debate. The cervical spine has been traditionally linked to cervicogenic headache; however, current evidence supports the presence of cervical musculoskeletal dysfunctions also in tension-type headache.

PURPOSE

This position paper discusses the most updated clinical and evidence-based data about the cervical spine in tension-type headache.

IMPLICATIONS

Subjects with tension-type headache exhibit concomitant neck pain, cervical spine sensitivity, forward head posture, limited cervical range of motion, positive flexion-rotation test and also cervical motor control disturbances. In addition, the referred pain elicited by manual examination of the upper cervical joints and muscle trigger points reproduces the pain pattern in tension-type headache. Current data supports that the cervical spine can be also involved in tension-type headache, and not just in cervicogenic headache. Several physical therapies including upper cervical spine mobilization or manipulation, soft tissue interventions (including dry needling) and exercises targeting the cervical spine are proposed for managing tension-type headache; however, the effectiveness of these interventions depends on a proper clinical reasoning since not all will be equally effective for all individuals with tension-type headache. Based on current evidence, we propose to use the terms cervical "component" and cervical "source" when discussing about headache. In such a scenario, in cervicogenic headache the neck can be the cause (source) of the headache whereas in tension-type headache the neck will have a component on the pain pattern, but it will be not the cause since it is a primary headache.

A new taxonomy was developed for overlap across 'overviews of systematic reviews': A meta-research study of research waste

Multiple 'overviews of reviews' conducted on the same topic ("overlapping overviews") represent a waste of research resources and can confuse clinicians making decisions amongst competing treatments. We aimed to assess the frequency and characteristics of overlapping overviews. MEDLINE, Epistemonikos and Cochrane Database of Systematic Reviews were searched for overviews that: synthesized reviews of health interventions and conducted systematic searches. Overlap was defined as: duplication of PICO eligibility criteria, and not reported as an update nor a replication. We categorized overview topics according to 22 WHO ICD-10 medical classifications, overviews as broad or narrow in scope, and overlap as identical, nearly identical, partial, or subsumed. Subsummation was defined as when broad overviews subsumed the populations, interventions and at least one outcome of another overview. Of 541 overviews included, 169 (31%) overlapped across similar PICO, fell within 13 WHO ICD-10 medical classifications, and 62 topics. 148/169 (88%) overlapping overviews were broad in scope. Fifteen overviews were classified as having nearly identical overlap (9%); 123 partial overlap (73%), and 31 subsumed (18%) others. One third of overviews overlapped in content and a majority covered broad topic areas. A multiplicity of overviews on the same topic adds to the ongoing waste of research resources, time, and effort across medical disciplines. Authors of overviews can use this study and the sample of overviews to identify gaps in the evidence for future analysis, and topics that are already studied, which do not need to be duplicated.

Clinical Reasoning Behind Non-Pharmacological Interventions for the Management of Headaches: A Narrative Literature Review

Headache is the clinical syndrome most commonly observed by neurologists in daily practice. Pharmacological and non-pharmacological treatments are commonly used for the management of headaches; however, the clinical reasoning behind these interventions is not properly applied. We conducted a narrative literature review using as data sources for academic PubMed, MEDLINE, EMBASE, AMED, CINAHL, EBSCO, PEDro, Cochrane Database of Systematic Reviews, Cochrane Collaboration Trials Register, and SCOPUS. This narrative literature review mainly considered systematic reviews, meta-analyses, randomised clinical trials, and expert opinions published after the year 2000 discussing clinical reasoning for application of non-pharmacological interventions in individuals with tension-type, migraine, and cervicogenic headaches. After the data extraction, we organized the literature thematically as follows: (1) mapping of theoretical aspects of non-pharmacological interventions; (2) summarizing most updated literature about effectiveness of non-pharmacological interventions grouped by targeted tissue and headache; (3) identifying research gaps in the existing literature and proposing hypotheses for better understanding of current clinical reasoning. We found that there are many non-pharmacological treatment strategies used for headaches, including beyond the tissue-based impairment treatments (bottom-up) and strategies targeting the central nervous system (top down). Bottom-up strategies include joint-biased, soft-tissue biased, or needling interventions, whereas top-down strategies include exercise and cognitive interventions. Evidence shows that the effectiveness of these interventions depends on the application of proper clinical reasoning, since not all strategies are effective for all headaches. For instance, evidence of non-pharmacological interventions is more controversial for migraines than for tension-type or cervicogenic headaches, since migraine pathogenesis involves activation of sub-cortical structures and the trigemino- vascular system, whereas pathogenesis of tension-type or cervicogenic headaches is most associated to musculoskeletal impairments of the cervical spine. We conclude that current literature suggests that not all non-pharmacological interventions are effective for all headaches, and that multimodal, not isolated, approaches seem to be more effective for patients with headaches. Most published studies have reported small clinical effects in the short term. This narrative literature review provides some hypotheses for discrepancies in the available literature and future research. Clinical reasoning should be applied to better understand the effects of non-pharmacological interventions.

Database combinations to retrieve systematic reviews in overviews of reviews: a methodological study

Background

When conducting an Overviews of Reviews on health-related topics, it is unclear which combination of bibliographic databases authors should use for searching for SRs. Our goal was to determine which databases included the most systematic reviews and identify an optimal database combination for searching systematic reviews.

Methods

A set of 86 Overviews of Reviews with 1219 included systematic reviews was extracted from a previous study. Inclusion of the systematic reviews was assessed in MEDLINE, CINAHL, Embase, Epistemonikos, PsycINFO, and TRIP. The mean inclusion rate (% of included systematic reviews) and corresponding 95% confidence interval were calculated for each database individually, as well as for combinations of MEDLINE with each other database and reference checking.

Results

Inclusion of systematic reviews was higher in MEDLINE than in any other single database (mean inclusion rate 89.7%; 95% confidence interval [89.0–90.3%]). Combined with reference checking, this value increased to 93.7% [93.2–94.2%]. The best combination of two databases plus reference checking consisted of MEDLINE and Epistemonikos (99.2% [99.0–99.3%]). Stratification by Health Technology Assessment reports (97.7% [96.5–98.9%]) vs. Cochrane Overviews (100.0%) vs. non-Cochrane Overviews (99.3% [99.1–99.4%]) showed that inclusion was only slightly lower for Health Technology Assessment reports. However, MEDLINE, Epistemonikos, and reference checking remained the best combination. Among the 10/1219 systematic reviews not identified by this combination, five were published as websites rather than journals, two were included in CINAHL and Embase, and one was included in the database ERIC.

Conclusions

MEDLINE and Epistemonikos, complemented by reference checking of included studies, is the best database combination to identify systematic reviews on health-related topics.

The Efficacy of Topical Basil Essential Oil on Relieving Migraine Headaches: A Randomized Triple-Blind Study

OBJECTIVE

Complementary therapies have been increasingly used for the prevention and treatment of migraine so that there is a need for studies in this setting. This study sought to determine the effects of basil essential oil on the severity and frequency of migraine attack headaches.

METHODS

A triple-blind clinical trial study was performed on 144 patients diagnosed with migraine. Patients were randomly allocated by a stratified method to four groups of 36 titled basil essential oil 2, 4, 6%, and placebo groups. Medications were used topically every 8 h for 3 successive months. In addition, each individual received 325 mg of acetaminophen every 12 h. The severity and frequency of migraine attacks were measured prior to the study, at weeks 2, 4, 8, and 12. The visual analog scale was used to measure pain intensity. The marginal model and generalized estimation equations were used to compare changes in the intensity and frequency of pain over time.

RESULTS

The interaction of the dose and time factors was significant on both pain intensity (p < 0.001) and frequency of attack (p < 0.001). The odds ratio of higher pain intensity and rate ratio of higher frequency of attack in the intervention groups compared to the placebo group were decreased over the study time.

CONCLUSION

Time lapse and higher doses of basil essential oil would reduce both the intensity and frequency of migraine attacks.

Melatonin and health: an umbrella review of health outcomes and biological mechanisms of action

BACKGROUND

Our aims were to evaluate critically the evidence from systematic reviews as well as narrative reviews of the effects of melatonin (MLT) on health and to identify the potential mechanisms of action involved.

METHODS

An umbrella review of the evidence across systematic reviews and narrative reviews of endogenous and exogenous (supplementation) MLT was undertaken. The Oxman checklist for assessing the methodological quality of the included systematic reviews was utilised. The following databases were searched: MEDLINE, EMBASE, Web of Science, CENTRAL, PsycINFO and CINAHL. In addition, reference lists were screened. We included reviews of the effects of MLT on any type of health-related outcome measure.

RESULTS

Altogether, 195 reviews met the inclusion criteria. Most were of low methodological quality (mean -4.5, standard deviation 6.7). Of those, 164 did not pool the data and were synthesised narratively (qualitatively) whereas the remaining 31 used meta-analytic techniques and were synthesised quantitatively. Seven meta-analyses were significant with P values less than 0.001 under the random-effects model. These pertained to sleep latency, pre-operative anxiety, prevention of agitation and risk of breast cancer.

CONCLUSIONS

There is an abundance of reviews evaluating the effects of exogenous and endogenous MLT on health. In general, MLT has been shown to be associated with a wide variety of health outcomes in clinically and methodologically heterogeneous populations. Many reviews stressed the need for more high-quality randomised clinical trials to reduce the existing uncertainties.

Assessing and treating primary headaches and cranio-facial pain in patients undergoing rehabilitation for neurological diseases

BACKGROUND

Pain is a very common condition in patient undergoing rehabilitation for neurological disease; however the presence of primary headaches and other cranio-facial pains, particularly when they are actually or apparently independent from the disability for which patient is undergoing rehabilitation, is often neglected. Diagnostic and therapeutic international and national guidelines, as well as tools for the subjective measure of head pain are available and should also be applied in the neurorehabilitation setting. This calls for searching the presence of head pain, independently from the rehabilitation needs, since pain, either episodic or chronic, interferes with patient performance by affecting physical and emotional status. Pain may also interfere with sleep and therefore hamper recovery.

METHODS

In our role of task force of the Italian Consensus Conference on Pain in Neurorehabilitation (ICCPN), we have elaborated specific recommendations for diagnosing and treating head pains in patients undergoing rehabilitation for neurological diseases.

RESULTS AND CONCLUSION

In this narrative review, we describe the available literature that has been evaluated in order to define the recommendations and outline the needs of epidemiological studies concerning headache and other cranio-facial pain in neurorehabilitation.

The risk associated with spinal manipulation: an overview of reviews

BACKGROUND

Spinal manipulative therapy (SMT) is a widely used manual treatment, but many reviews exist with conflicting conclusions about the safety of SMT. We performed an overview of reviews to elucidate and quantify the risk of serious adverse events (SAEs) associated with SMT.

METHODS

We searched five electronic databases from inception to December 8, 2015. We included reviews on any type of studies, patients, and SMT technique. Our primary outcome was SAEs. Quality of the included reviews was assessed using a measurement tool to assess systematic reviews (AMSTAR). Since there were insufficient data for calculating incidence rates of SAEs, we used an alternative approach; the conclusions regarding safety of SMT were extracted for each review, and the communicated opinion were judged by two reviewers independently as safe, harmful, or neutral/unclear. Risk ratios (RRs) of a review communicating that SMT is safe and meeting the requirements for each AMSTAR item, were calculated.

RESULTS

We identified 283 eligible reviews, but only 118 provided data for synthesis. The most frequently described adverse events (AEs) were stroke, headache, and vertebral artery dissection. Fifty-four reviews (46%) expressed that SMT is safe, 15 (13%) expressed that SMT is harmful, and 49 reviews (42%) were neutral or unclear. Thirteen reviews reported incidence estimates for SAEs, roughly ranging from 1 in 20,000 to 1 in 250,000,000 manipulations. Low methodological quality was present, with a median of 4 of 11 AMSTAR items met (interquartile range, 3 to 6). Reviews meeting the requirements for each of the AMSTAR items (i.e. good internal validity) had a higher chance of expressing that SMT is safe.

CONCLUSIONS

It is currently not possible to provide an overall conclusion about the safety of SMT; however, the types of SAEs reported can indeed be significant, sustaining that some risk is present. High quality research and consistent reporting of AEs and SAEs are needed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015030068 .

Physical therapy for headaches

Background Headache is the medical problem most commonly observed by neurologists. Non-pharmacological treatments are commonly demanded by individuals with headaches, but their evidence of effectiveness is conflicting. Aim The current review provides an updated discussion on what is supported by current scientific evidence about physical therapies for tension-type headache (TTH), migraine, and cervicogenic headache (CeH), and which gaps there still may be in our understanding of the interventions. Methods PubMed, MEDLINE, EMBASE, AMED, CINAHL, EBSCO, Cochrane Database of Systematic Reviews, Cochrane Collaboration Trials Register, PEDro, and SCOPUS were searched from their inception through March 2015. Results/Discussion Several physical therapies including spinal joint manipulation/mobilization, soft tissue interventions, therapeutic exercises and needling therapies are proposed to be effective for the management of headaches. Current evidence has shown that the effectiveness of these interventions will depend on proper clinical reasoning since not all interventions are equally effective for all headache pain conditions. For instance, evidence of physical therapy in migraine is more controversial than in TTH, since migraine pathogenesis involves activation of sub-cortical structures and the trigemino-vascular system, whereas pathogenesis of TTH is more associated with musculoskeletal disorders, e.g. muscle pain. It seems that multimodal approaches including different interventions are more effective for patients with TTH, migraine and CeH.

Clinical reasoning for manual therapy management of tension type and cervicogenic headache

In recent years, there has been an increasing knowledge in the pathogenesis and better management of chronic headaches. Current scientific evidence supports the role of manual therapies in the management of tension type and cervicogenic headache, but the results are still conflicting. These inconsistent results can be related to the fact that maybe not all manual therapies are appropriate for all types of headaches; or maybe not all patients with headache will benefit from manual therapies. There are preliminary data suggesting that patients with a lower degree of sensitization will benefit to a greater extent from manual therapies, although more studies are needed. In fact, there is evidence demonstrating the presence of peripheral and central sensitization in chronic headaches, particularly in tension type. Clinical management of patients with headache needs to extend beyond local tissue-based pathology, to incorporate strategies directed at normalizing central nervous system sensitivity. In such a scenario, this paper exposes some examples of manual therapies for tension type and cervicogenic headache, based on a nociceptive pain rationale, for modulating central nervous system hypersensitivity: trigger point therapy, joint mobilization, joint manipulation, exercise, and cognitive pain approaches.

Therapeutic options for cervicogenic headache

The term cervicogenic headache (CeH) describes a syndrome originating from the cervical spine. There are a variety of therapeutic approaches used for the management of CeH, but scientific evidence of their effectiveness is scarce. No medication drug has proven to be effective. The evidence for greater occipital nerve blocks, cervical nerve blockades, facet joint injections and surgical procedures is limited. Several physical therapy interventions are proposed for CeH, with spinal manipulation and soft tissue interventions being the most commonly used. However, the lack of solid evidence of positive effects and risks of serious complications for spinal manipulation should be considered in favor of other physical therapy interventions associated with less risk. The inconsistent results in the literature can be related to the fact that maybe not all therapeutic interventions are appropriate for all patients with CeH or maybe not all patients with CeH will benefit from particular interventions.