Intra- and inter-session reliability of electrical detection and pain thresholds of cutaneous and muscle primary afferents in the lower back of healthy individuals.

To advance evidence-based practice and targeted treatments of low back pain (LBP), a better pathophysiological understanding and reliable outcome measures are required. The processing of nociceptive information from deeper somatic structures (e.g., muscle, fascia) might play an essential role in the pathophysiology of LBP. In this study, we measured the intra- and inter-session reliability of electrical detection and pain thresholds of cutaneous and muscle primary afferents of the lower back. Twenty healthy participants attended two study visits separated by 27.7 ± 1.7 days. To determine the location-specific electrical detection threshold (EDT) and pain threshold (EPT), needle electrodes were inserted in the epidermal layer over, and in the lumbar erector spinae muscle. Additionally, established quantitative sensory testing (QST) parameters were assessed. Reliability was determined by differences between measurements, intraclass correlation coefficients (ICC2,1), Bland-Altman plots, and standard error of measurement (SEM). Correspondence between QST parameters and electrical thresholds was assessed using Pearson's correlation. Except for cutaneous EPT, no significant (p ≤ 0.05) intra- and inter-session differences were observed. Excellent intra-session reliability was shown for cutaneous and intramuscular electrical stimulations and all QST parameters (ICC: 0.76-0.93). Inter-session reliabilities were good (ICC: 0.74-0.75) except for electrical stimulations (ICC: 0.08-0.36). Limits of agreement and SEM were higher for inter-session than intra-session. A medium to strong relationship was found between electrical and mechanical/pressure pain thresholds. In conclusion, cutaneous and intramuscular electrical stimulation will potentially close an important diagnostic gap regarding the selective examination of deep tissue afferents and provide location-specific information for the excitability of non-nociceptive and nociceptive afferents.

Translation and validation of the German version of the Young Spine Questionnaire.

BACKGROUND: Back pain in childhood and adolescence increases the risk for back pain in adulthood, but validated assessment tools are scarce. The aim of this study was to validate the Young Spine Questionnaire (YSQ) in a German version (G-YSQ) in children and adolescents. METHODS: Children and adolescents between 10 and 16 years (N = 240, 166 females, mean age = 13.05 ± 1.70 years), recruited in chiropractic practices and schools, completed the G-YSQ (translated according to scientific guidelines) and the KIDSCREEN-10 (assessing health-related quality of life) at three time points. Test-retest reliability was determined calculating intraclass correlation coefficients [ICC(3,1)] using start and two week-data. Construct validity was investigated testing a priori hypotheses. To assess responsiveness, the patients additionally filled in the Patient Global Impression of Change (PGIC) after three months and the area under the curve (AUC) of receiver operating curves was calculated. RESULTS: The ICC(3,1) was 0.88 for pain intensity and pain frequency, indicating good reliability, 0.68 for week prevalence and 0.60 for point prevalence, indicating moderate reliability. Pain intensity, frequency and prevalence differed between patients and controls (p < 0.001) and, except point prevalence, between older (> 12 years) and younger control participants (p < 0.01). Health-related quality of life of participants with severe pain (in one or several spinal regions) was lower (KIDSCREEN-10, total score: F(4,230) = 7.26, p < 0.001; KIDSCREEN-10, self-rated general health: H(4) = 51.94, p < 0.001) than that of participants without pain or with moderate pain in one spinal region. Thus, altogether these findings indicate construct validity of the G-YSQ. The AUC was 0.69 (95 % CI = 0.57-0.82) and 0.67 (95 % CI = 0.54-0.80) for week and point prevalence, respectively, indicating insufficient responsiveness of the G-YSQ. CONCLUSIONS: Apart from the question on point prevalence, construct validity and sufficient test-retest reliability was shown for the G-YSQ. However, its responsiveness needs to be improved, possibly by asking for pain frequency during the last week instead of (dichotomous) week prevalence. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02955342, registered 07/09/2016, https://clinicaltrials.gov/ct2/results?cond=&term=NCT02955342&cntry=CH&state=&city=Zurich&dist= .

Prospective Back Pain Trajectories or Retrospective Recall-Which Tells Us Most About the Patient?

In patients with low back pain (LBP), a visually identified retrospective pain trajectory often mismatches with a trajectory derived from prospective repeated measures. To gain insight into the clinical relevance of the 2 trajectory types, we investigated which showed a higher association with clinical outcomes. Participants were 724 adults seeking care for LBP in Danish chiropractic primary care. They answered weekly short-message-services on pain intensity and frequency over 52 weeks, which we translated into 8 trajectory classes. After 52 weeks, participants selected a retrospective visual pain trajectory from the same 8 trajectory classes. Clinical outcomes included disability, back/leg pain intensity, back beliefs, and work ability. The patient-selected pain trajectory classes were more strongly associated with clinical outcomes than the short-message-service trajectory classes at baseline, at follow-up, and with outcome changes between baseline and follow-up. This held across all 5 clinical outcomes, with the strongest associations observed at week 52 and the weakest at baseline. Patients' retrospective assessment of their LBP is more strongly associated with their clinical status than their prospective assessments translated into trajectory classes. This suggests that retrospective assessments of pain trajectories may provide valuable information not captured by prospective assessments. Researchers collecting prospective pain data should know that the captured pain trajectories are not strongly reflected in patients' perceptions of clinical status. Patients' retrospective assessments seem to offer an interpretation of their pain course that is likely more clinically relevant in understanding the perceived impact of their condition than trajectories based on repeated measures. PERSPECTIVE: Prospective pain data inadequately reflect patients' clinical status. Retrospective assessments provide a more clinically valuable understanding of the impact of their condition.

Mechanisms of manipulation: a systematic review of the literature on immediate anatomical structural or positional changes in response to manually delivered high-velocity, low-amplitude spinal manipulation.

BACKGROUND: Spinal manipulation (SM) has been claimed to change anatomy, either in structure or position, and that these changes may be the cause of clinical improvements. The aim of this systematic review was to evaluate and synthesise the peer-reviewed literature on the current evidence of anatomical changes in response to SM. METHODS: The review was registered with PROSPERO (CRD42022304971) and reporting was guided by the standards of the PRISMA Statement. We searched Medline, Embase, CINAHL, AMED, Cochrane Library all databases, PEDro, and the Index to Chiropractic Literature from inception to 11 March 2022 and updated on 06 June 2023. Search terms included manipulation, adjustment, chiropractic, osteopathy, spine and spine-related structures. We included primary research studies that compared outcomes with and without SM regardless of study design. Manipulation was defined as high-velocity, low-amplitude thrust delivered by hand to the spine or directly related joints. Included studies objectively measured a potential change in an anatomical structure or in position. We developed a novel list of methodological quality items in addition to a short, customized list of risk of bias (RoB) items. We used quality and RoB items together to determine whether an article was credible or not credible. We sought differences in outcomes between SM and control groups for randomised controlled trials and crossover studies, and between pre- and post-SM outcomes for other study designs. We reported, in narrative form, whether there was a change or not. RESULTS: The search retrieved 19,572 articles and 20 of those were included for review. Study topics included vertebral position (n = 3) facet joint space (n = 5), spinal stiffness (n = 3), resting muscle thickness (n = 6), intervertebral disc pressure (n = 1), myofascial hysteresis (n = 1), and further damage to already damaged arteries (n = 1). Eight articles were considered credible. The credible articles indicated that lumbar facet joint space increased and spinal stiffness decreased but that the resting muscle thickness did not change. CONCLUSION: We found few studies on this topic. However, there are two promising areas for future study: facet joint space and spinal stiffness. A research strategy should be developed with funding for high quality research centres.

A two-year follow-up: Twitter activity regarding misinformation about spinal manipulation, chiropractic care and boosting immunity during the COVID-19 pandemic.

BACKGROUND: Spinal manipulative therapy (SMT) is offered by many health professions, most often by chiropractors. While SMT can be effective for some musculoskeletal disorders, there is no evidence that SMT improves human immunity in a clinically meaningful way. Despite this, we showed previously that Twitter misinformation about chiropractic/SMT  improving immunity increased sharply at the start of the COVID-19 pandemic. Here, we perform a two-year follow-up. METHODS: We previously employed specialized software (i.e. Talkwalker) to search the entirety of Twitter activity in the  months before and after the COVID-19 pandemic was declared (March 11, 2020). In this paper, we conducted follow-up searches over two successive 12 month periods using terms related to SMT, immunity and chiropractic. The resulting tweets were then coded into those promoting/refuting a relation between SMT and immunity (tone) and messaging about chiropractic/interventions (content). Further analyses were performed to subcategorize tweet content, tally likes, retweets and followers, and evaluate refuting tweets and the country of origin. Finally, we created a chronology of Twitter activity superimposed with dates of promoting or refuting activities undertaken by chiropractic organizations. RESULTS: Over the 27 month study period, Twitter activity peaked on March 31, 2020 then declined continuously. As in our first paper, our follow-up data showed that (1) the ratio of refuting/promoting tweets remained constant and (2) tweets that refuted a relationship between SMT and immunity were substantially more liked, retweeted and followed than those promoting. We also observed that promoting tweets suggesting that SMT improves immunity decreased more rapidly. Overwhelmingly, promoting tweets originated in the USA while refuting tweets originated in Canada, Europe and Australia. The timing of the decline in peak Twitter activity, together with a parallel decline in tweets claiming that SMT improves immunity, was coincident with initiatives by chiropractic organizations and regulators targeting misinformation. CONCLUSION: Overwhelmingly, Twitter activity during the COVID-19 pandemic focussed on refuting a relation between chiropractic/SMT and immunity. A decline in Twitter activity promoting a relation between SMT and immunity was observed to coincide with initiatives from chiropractic organizations and regulators to refute these claims. The majority of misinformation about this topic is generated in the United States.

Spinal manipulation characteristics: a scoping literature review of force-time characteristics.

BACKGROUND: Spinal manipulation (SM) is a recommended and effective treatment for musculoskeletal disorders. Biomechanical (kinetic) parameters (e.g. preload/peak force, rate of force application and thrust duration) can be measured during SM, quantifying the intervention. Understanding these force-time characteristics is the first step towards identifying possible active ingredient/s responsible for the clinical effectiveness of SM. Few studies have quantified SM force-time characteristics and with considerable heterogeneity evident, interpretation of findings is difficult. The aim of this study was to synthesise the literature describing force-time characteristics of manual SM. METHODS: This scoping literature review is reported following the Preferred Reporting Items for Scoping Reviews (PRISMA-ScR) statement. Databases were searched from inception to October 2022: MEDLINE (Ovid), Embase, CINAHL, ICL, PEDro and Cochrane Library. The following search terms and their derivatives were adapted for each platform: spine, spinal, manipulation, mobilization or mobilisation, musculoskeletal, chiropractic, osteopathy, physiotherapy, naprapathy, force, motor skill, biomechanics, dosage, dose-response, education, performance, psychomotor, back, neck, spine, thoracic, lumbar, pelvic, cervical and sacral. Data were extracted and reported descriptively for the following domains: general study characteristics, number of and characteristics of individuals who delivered/received SM, region treated, equipment used and force-time characteristics of SM. RESULTS: Of 7,607 records identified, 66 (0.9%) fulfilled the eligibility criteria and were included in the analysis. Of these, SM was delivered to the cervical spine in 12 (18.2%), the thoracic spine in 40 (60.6%) and the lumbopelvic spine in 19 (28.8%) studies. In 6 (9.1%) studies, the spinal region was not specified. For SM applied to all spinal regions, force-time characteristics were: preload force (range: 0-671N); peak force (17-1213N); rate of force application (202-8700N/s); time to peak thrust force (12-938ms); and thrust duration (36-2876ms). CONCLUSIONS: Considerable variability in the reported kinetic force-time characteristics of SM exists. Some of this variability is likely due to differences in SM delivery (e.g. different clinicians) and the measurement equipment used to quantify force-time characteristics. However, improved reporting in certain key areas could facilitate more sophisticated syntheses of force-time characteristics data in the future. Such syntheses could provide the foundation upon which dose-response estimates regarding the clinical effectiveness of SM are made.

Spinal mobilization force-time characteristics: A scoping literature review.

BACKGROUND: Spinal mobilization (SMob) is often included in the conservative management of spinal pain conditions as a recommended and effective treatment. While some studies quantify the biomechanical (kinetic) parameters of SMob, interpretation of findings is difficult due to poor reporting of methodological details. The aim of this study was to synthesise the literature describing force-time characteristics of manually applied SMob. METHODS: This study is reported in accordance with the Preferred Reporting Items for Scoping Reviews (PRISMA-ScR) statement. Databases were searched from inception to October 2022: MEDLINE (Ovid), Embase, CINAHL, ICL, PEDro and Cochrane Library. Data were extracted and reported descriptively for the following domains: general study characteristics, number of and characteristics of individuals who delivered/received SMob, region treated, equipment used and force-time characteristics of SMob. RESULTS: There were 7,607 records identified and of these, 36 (0.5%) were included in the analysis. SMob was delivered to the cervical spine in 13 (36.1%), the thoracic spine in 3 (8.3%) and the lumbopelvic spine in 18 (50.0%) studies. In 2 (5.6%) studies, spinal region was not specified. For SMob applied to all spinal regions, force-time characteristics were: peak force (0-128N); duration (10-120s); frequency (0.1-4.5Hz); and force amplitude (1-102N). CONCLUSIONS: This study reports considerable variability of the force-time characteristics of SMob. In studies reporting force-time characteristics, SMob was most frequently delivered to the lumbar and cervical spine of humans and most commonly peak force was reported. Future studies should focus on the detailed reporting of force-time characteristics to facilitate the investigation of clinical dose-response effects.

The effectiveness of spinal manipulative therapy procedures for spine pain: protocol for a systematic review and network meta-analysis.

BACKGROUND: Spinal manipulative therapy (SMT) is a guideline-recommended treatment option for spinal pain. The recommendation is based on multiple systematic reviews. However, these reviews fail to consider that clinical effects may depend on SMT "application procedures" (i.e., how and where SMT is applied). Using network meta-analyses, we aim to investigate which SMT "application procedures" have the greatest magnitude of clinical effectiveness for reducing pain and disability, for any spinal complaint, at short-term and long-term follow-up. We will compare application procedural parameters by classifying the thrust application technique and the application site (patient positioning, assisted, vertebral target, region target, Technique name, forces, and vectors, application site selection approach and rationale) against: 1. Waiting list/no treatment; 2. Sham interventions not resembling SMT (e.g., detuned ultrasound); 3. Sham interventions resembling SMT; 4. Other therapies not recommended in clinical practice guidelines; and 5. Other therapies recommended in clinical practice guidelines. Secondly, we will examine how contextual elements, including procedural fidelity (whether the SMT was delivered as planned) and clinical applicability (whether the SMT is similar to clinical practice) of the SMT. METHODS: We will include randomized controlled trials (RCT) found through three search strategies, (i) exploratory, (ii) systematic, and (iii) other known sources. We define SMT as a high-velocity low-amplitude thrust or grade V mobilization. Eligibility is any RCT assessing SMT against any other type of SMT, any other active or sham intervention, or no treatment control on adult patients with pain in any spinal region. The RCTs must report on continuous pain intensity and/or disability outcomes. Two authors will independently review title and abstract screening, full-text screening, and data extraction. Spinal manipulative therapy techniques will be classified according to the technique application and choice of application sites. We will conduct a network-meta analysis using a frequentist approach and multiple subgroup and sensitivity analyses. DISCUSSION: This will be the most extensive review of thrust SMT to date, and will allow us to estimate the importance of different SMT application procedures used in clinical practice and taught across educational settings. Thus, the results are applicable to clinical practice, educational settings, and research studies. PROSPERO registration: CRD42022375836.

Musculoskeletal healthcare at a Swiss university hospital chiropractic medicine outpatient clinic in 2019: a health services research study.

BACKGROUND: The Balgrist University Hospital in Zurich, Switzerland, is an academic hospital focused on musculoskeletal disorders. An integrated chiropractic medicine clinic provides chiropractic care to a broad patient population. This health services research study aims to advance understanding of chiropractic healthcare service for quality assurance and healthcare quality improvement. METHODS: We performed an observational clinical cohort study at the Balgrist chiropractic medicine outpatient clinic in 2019. The records of all patients with initial visits or returning initial visits (> 3 months since last visit) and their subsequent visits from January 1, 2019, to December 31, 2019, were used to create the study dataset. Data collected included demographic characteristics, diagnoses, imaging data, conservative treatments, surgeries, and other clinical care data. Descriptive statistics were used to summarize data. RESULTS: 1844 distinct patients (52% female, mean age 48 ± 17 years) were eligible and included in the study. 1742 patients had a single initial visit, 101 had 2 initial visits, and 1 patient had 3 initial visits during the study period (total of 1947 initial visit records). The most common main diagnoses were low back pain (42%; 95% CI 40-46%), neck pain (22%; 20-24%), and thoracic pain (8%; 7-9%). 32% of patients presented with acute (< 4 weeks) symptoms, 11% subacute (4-12 weeks), and 57% chronic (> 12 weeks). Patients had a median of 5 chiropractic visits during their episode of care within a median of 28 days duration. Only 49% (95% CI 47-52%) of patient records had a clinical outcome that was extractable from routine clinical documentation in the hospital information system. CONCLUSION: This health services study provides an initial understanding of patient characteristics and healthcare delivered in a Swiss academic hospital chiropractic outpatient setting and areas for improved clinical data quality assurance. A more concerted effort to systematically collect patient reported outcome measures would be a worthwhile healthcare quality improvement initiative.

Responsiveness of the German version of the Neck Disability Index in chronic neck pain patients: a prospective cohort study with a seven-week follow-up.

BACKGROUND: The need for an efficient and feasible strategy to deal with neck pain has a high priority for many countries. Validated assessment tools like the Neck Disability Index (NDI) to evaluate the functional status of a neck pain patient are urgently needed to treat and to follow-up patients purposefully. A German version (NDI-G) was shown to be valid and reliable, but has so far not been tested for responsiveness. The aim of this study was to evaluate the NDI-G`s responsiveness. METHODS: This was a prospective cohort study with a seven-week follow-up. Fifty chronic neck pain patients filled out NDI-G twice. Additionally, the Patients' Global Impression of Change score (PGIC) was assessed at follow-up. Wilcoxon and Spearman tests were used to assess direction and strength of the association between the change in NDI-G and PGIC. The receiver operating characteristics method and the area under the curve (AUC) were calculated to assess sensitivity and specificity of the NDI-G change over time. RESULTS: The Wilcoxon test showed statistically significant differences for NDI-G at baseline and follow-up in the total sample, the "clinically improved" and "clinically not improved" subgroups as indicated in the PGIC. Spearman test resulted in a moderate correlation between the NDI-G and the PGIC (rS = -0.53, p = 0.01) at follow-up. AUC showed an acceptable discrimination [AUC = 0.78 (95% confidence interval 0.64 - 0.91)] of the NDI-G, with a cutoff score of 1.5, between clinically improved and clinically not improved patients, based on the PGIC. CONCLUSIONS: The NDI-G is responsive to change in chronic neck pain. Together with the results of a previous study on its validity and reliability, the NDI-G can be recommended for research and clinical settings in patients with neck pain in German speaking countries. TRIAL REGISTRATION: NCT02676141. February 8, 2016.

Posterior to anterior spinal stiffness measured in a sample of 127 secondary care low back pain patients.

BACKGROUND: The sensation of spinal stiffness is a commonly reported symptom among back pain patients, with the clinical assessment of spinal stiffness usually being part of the decision-making process when deciding on providing manual treatment of low back pain. While any relationship between spinal stiffness and low back pain is likely to be multifactorial, prior exploration of this relationship has been overly simplistic (e.g., univariate regression analyses). The purpose of this study was to address this gap by taking a broader approach to compare instrumented measures of spinal stiffness to demographic characteristics, pain phenotypes, psychometrics, and spine-related disability in a sample of secondary care low back pain patients using multivariate regression analysis. METHODS: Instrumented spinal stiffness measures from 127 patients in secondary care were used to calculate terminal and global spinal stiffness scores. A best subset analysis was used to find the subsets of 14 independent variables that most accurately predicted stiffness based on the evaluation of the adjusted R-square, Akaike Information Criteria, and the Bayesian Information Criteria. FINDINGS: In the resulting multivariate models, sex (p < 0.001) and age (p < 0.001) were the primary determinants of terminal stiffness, while global stiffness was primarily determined by age (p = 0.003) and disability (p = 0.024). INTERPRETATION: Instrumented measures of spinal stiffness are multifactorial in nature, and future research into this area should make use of multivariate analyses.

Misinformation about spinal manipulation and boosting immunity: an analysis of Twitter activity during the COVID-19 crisis.

BACKGROUND: Social media has become an increasingly important tool in monitoring the onset and spread of infectious diseases globally as well monitoring the spread of information about those diseases. This includes the spread of misinformation, which has been documented within the context of the emerging COVID-19 crisis. Understanding the creation, spread and uptake of social media misinformation is of critical importance to public safety. In this descriptive study, we detail Twitter activity regarding spinal manipulative therapy (SMT) and claims it increases, or "boosts", immunity. Spinal manipulation is a common intervention used by many health professions, most commonly by chiropractors. There is no clinical evidence that SMT improves human immunity. METHODS: Social media searching software (Talkwalker Quick Search) was used to describe Twitter activity regarding SMT and improving or boosting immunity. Searches were performed for the 3 months and 12 months before March 31, 2020 using terms related to 1) SMT, 2) the professions that most often provide SMT and 3) immunity. From these searches, we determined the magnitude and time course of Twitter activity then coded this activity into content that promoted or refuted a SMT/immunity link. Content themes, high-influence users and user demographics were then stratified as either promoting or refuting this linkage. RESULTS: Twitter misinformation regarding a SMT/immunity link increased dramatically during the onset of the COVID crisis. Activity levels (number of tweets) and engagement scores (likes + retweets) were roughly equal between content promoting or refuting a SMT/immunity link, however, the potential reach (audience) of tweets refuting a SMT/immunity link was 3 times higher than those promoting a link. Users with the greatest influence on Twitter, as either promoters or refuters, were individuals, not institutions or organizations. The majority of tweets promoting a SMT/immunity link were generated in the USA while the majority of refuting tweets originated from Canada. CONCLUSION: Twitter activity about SMT and immunity increased during the COVID-19 crisis. Results from this work have the potential to help policy makers and others understand the impact of SMT misinformation and devise strategies to mitigate its impact.

Exploring the definition of «acute¼ neck pain: a prospective cohort observational study comparing the outcomes of chiropractic patients with 0-2 weeks, 2-4 weeks and 4-12 weeks of symptoms.

BACKGROUND: Neck pain is a common complaint in chiropractic patients. Amongst other baseline variables, numerous studies identify duration of symptoms as a strong predictor of outcome in neck pain patients. The usual time frame used for 'acute' onset of pain is between 0 and 4 weeks. However, the appropriateness of this time frame has been challenged for chiropractic low back pain patients. Therefore, the purpose of this study was to compare outcomes in neck pain patients with 0-2 vs 2-4 and 4-12 weeks of symptoms undergoing chiropractic treatment. METHODS: This is a prospective cohort observational study with 1 year follow-up including 495 patients whose data was collected between October 2009 and March 2015. Patients were divided into high-acute (0-2 weeks), mid-acute (2-4 weeks) and subacute (4-12 weeks) corresponding to duration of their symptoms at initial treatment. Patients completed the numerical pain rating scale (NRS) and Bournemouth questionnaire for neck pain (BQN) at baseline. At follow-up time points of 1 week, 1 month, 3 months, 6 months and 1 year the NRS and BQN were completed along with the Patient Global Impression of Change (PGIC) scale. The PGIC responses were dichotomized into 'improved' and 'not improved' patients and compared between the 3 subgroups. The Chi-square test was used to compare improved patients between the 3 subgroups and the unpaired Student's t-test was used for the NRS and BQN change scores. RESULTS: The proportion of patients 'improved' was only significantly higher for patients with symptoms of 0-2 weeks compared to 2-4 weeks at the 1 week outcome time point (p = 0.015). The NRS changes scores were significantly greater for patients with 2-4 weeks of symptoms compared to 4-12 weeks of symptoms only at 1 week (p = 0.035). CONCLUSIONS: The time period of 0-4 weeks of symptoms as the definition of "acute" neck pain should be maintained. Independent of the exact duration of symptoms, medium-term and long-term outcome is favourable for acute as well as subacute neck pain patients. TRIAL REGISTRATION: Not applicable for prospective cohort studies. Ethics approval prior to study EK 19/2009.