Efficacy of Physical Therapy on Nociceptive Pain Processing Alterations in Patients with Chronic Musculoskeletal Pain: A Systematic Review and Meta-analysis

CPM-Related Mechanisms Could Play a Key Role in the Effects on Pain Sensitivity Induced by Manual Therapy: Three Crossover Trials Investigating the Effects of Manual Pressure

Objective: The aim of this study is to assess whether pain-inducing manual pressure (PIMP) leads to effects on pressure pain threshold (PPT) mediated by conditioned pain modulation (CPM) and whether these effects are influenced by the intensity and repetition of the stimulus. Additionally, the influence of psychological factors and physical activity on the response to PIMP was explored. Methods: A total of 72 pain-free students were randomly assigned to three crossover trials. Trial 1 compared the effects of PIMP with the cold pressor task and pain-inducing electrostimulation. Trial 2 compared the effects of manual pressure that elicited moderate pain, mild pain, and no pain. Trial 3 compared a single PIMP stimulation with four stimuli applied at the same site or at different sites. Results: PIMP produced a lower increase in PPT than cold pressor task and no difference with electrostimulation. Manual pressure that caused moderate pain led to a greater increase in PPT compared to mild pain and pain-free application. Repetition of PIMP stimulus, whether at the same or different sites, did not significantly increase PPT compared to a single stimulation. No association with psychological factors or physical activity was found. Conclusions: PIMP produces an increase in PPT, suggesting the involvement of CPM-related mechanisms.

Restoration of normal central pain processing following manual therapy in nonspecific chronic neck pain

OBJECTIVE

To determine if a 4-week manual therapy treatment restores normal functioning of central pain processing mechanisms in non-specific chronic neck pain (NSCNP), as well as the existence of a possible relationship between changes in pain processing mechanisms and clinical outcome.

DESIGN

Cohort study.

METHODS

Sixty-three patients with NSCNP, comprising 79% female, with a mean age of 45.8 years (standard deviation: 14.3), received four treatment sessions (once a week) of manual therapy including articular passive mobilizations, soft tissue mobilization and trigger point treatment. Pressure pain thresholds (PPTs), conditioned pain modulation (CPM) and temporal summation of pain (TSP) were evaluated at baseline and after treatment completion. Therapy outcome was measured using the Global Rating of Change Scale (GROC), the Neck disability Index (NDI), intensity of pain during the last 24 hours, Tampa Scale of Kinesiophobia (TSK) and Pain Catastrophizing Scale (PCS). Two sets of generalized linear mixed models with Gaussian response and the identity link were employed to evaluate the effect of the intervention on clinical, psychological and psychophysical measures and the association between psychophysical and clinical outcomes.

RESULTS

Following treatment, an increased CPM response (Coefficient: 0.89; 95% credibility interval = 0.14 to 1.65; P = .99) and attenuated TSP (Coefficient: -0.63; 95% credibility interval = -0.82 to -0.43; P = 1.00) were found, along with amelioration of pain and improved clinical status. PPTs at trapezius muscle on the side of neck pain were increased after therapy (Coefficient: 0.22; 95% credibility interval = 0.03 to 0.42; P = .98), but not those on the contralateral trapezius and tibialis anterior muscles. Only minor associations were found between normalization of TSP/CPM and measures of clinical outcome.

CONCLUSION

Clinical improvement after manual therapy is accompanied by restoration of CPM and TSP responses to normal levels in NSCNP patients. The existence of only minor associations between changes in central pain processing and clinical outcome suggests multiple mechanisms of action of manual therapy in NSCNP.

Influence of central aspects of pain on self-management in people with chronic low back pain

OBJECTIVE

This observational study investigated whether central aspects of pain are associated with self-management domains in individuals with chronic low back pain (CLBP) undertaking a pain management program.

METHODS

Individuals with CLBP provided pain sensitivity and self-management data at baseline (n = 97) and 3-months (n = 87). Pressure pain detection threshold (PPT) at the forearm, temporal summation (TS) and conditioned pain modulation (CPM), Widespread Pain Index (WPI), and a Central Aspects of Pain factor (CAPf) were considered as central aspects of pain. Self-management was measured using the 8 domains of the Health Education Impact Questionnaire, as well as Pain Self Efficacy and Health Care Utilisation questionnaires.

RESULTS

PPT, CPM, WPI and CAPf predicted worse performance in several self-management domains at 3-months (r = 0.21 to 0.54, p < 0.05 overall). In multivariable regression models (adjusted for baseline scores of self-management, depression, catastrophization, pain and fatigue) low PPT, high TS, and high CAPf at baseline predicted poorer self-management at 3 months (R2 =0.14 to 0.52, β = -0.37 to 0.35, p < 0.05).

CONCLUSIONS

Central aspects of pain are associated with impaired self-management, over and above effects of pain intensity, fatigue, depression and catastrophizing.

PRACTICE IMPLICATIONS

Treatments that target central aspects of pain might help improve self-management in people with CLBP.

An overview of systematic reviews examining the quantitative sensory testing-derived hypoalgesic effects of manual therapy for musculoskeletal pain

BACKGROUND

Changes in quantitative sensory testing (QST) after manual therapy can provide insight into pain relief mechanisms. Prior systematic reviews have evaluated manual-therapy-induced QST change. This overview of systematic reviews aims to consolidate this body of literature and critically review evidence on the hypoalgesic effects of manual therapy in clinical populations.

METHODS

A comprehensive search was conducted on PubMed, CINAHL, PsycInfo, and Embase. Peer-reviewed systematic reviews with or without meta-analysis were eligible if the reviews examined the effect of manual therapy compared to non-manual therapy interventions on QST outcomes in clinical populations. Methodological quality was assessed with the AMSTAR 2 tool. Meta-analysis results and qualitative (non-meta-analysis) interpretations were summarized by type of manual therapy. Overlap of studies was examined with the corrected covered area (CCA) index.

RESULTS

Thirty systematic reviews, including 11 meta-analyses, met inclusion. There was a slight overlap in studies (CCA of 1.72% for all reviews and 1.69% for meta-analyses). Methodological quality was predominantly low to critically low. Eight (27%) reviews examined studies with a range of manual therapy types, 13 (43%) reviews focused on joint-biased manual therapy, 7 (23%) reviews focused on muscle-biased manual therapy, and 2 (7%) reviews focused on nerve-biased manual therapy. Twenty-nine (97%) reviews reported on pressure pain threshold (PPT). Meta-analytic results demonstrated conflicting evidence that manual therapy results in greater hypoalgesic effects compared to other interventions or controls.

CONCLUSION

Our overview of QST effects, which has relevance to mechanisms underlying hypoalgesia, shows conflicting evidence from mostly low to critically low systematic reviews.

Whole-Body Electrostatic Pain Treatment in Adults with Chronic Pain: A Prospective Multicentric Observational Clinical Trial

INTRODUCTION

In the treatment of patients with chronic pain, whole-body electrostatic therapy using the Elosan Cabin C1 has been proposed as an adjunctive therapy. So far, data on the use of this cabin are limited. Promising results with a significant reduction in pain scores have been obtained in a small group of patients. However, treatment with Elosan Cabin C1 has not been the subject of evaluation in a larger patient population. The aim of this study was to investigate the efficacy and adverse effects of electrostatic treatment in such a population.

METHODS

Prospective, multi-center, observational clinical trial conducted in daily practice in a large adult ambulatory population with chronic pain. Each patient received eight weekly Elosan C1 treatment sessions for up to 9 weeks. Treatment was added to an established conservative pain management. Pain scores (visual analog scale (VAS) 0-100, primary outcome) and sleep quality (seven-point Likert scale, secondary outcome) were assessed before, during, and at the end of the treatment period; quality of life (SF-12: Physical Component Summary = PCS, Mental Component Summary = MCS; secondary outcome) was assessed before and at the end of the treatment period. Subgroup analyses were performed for sex, age, duration of pain, initial pain location, pain entity, and pain medication at the start of treatment.

RESULTS

A total of 192 patients were enrolled, 143 patients (74.5%) had a complete set of 8 treatment sessions. A reduction in pain scores from 68 ± 14 points to 47 ± 22 points was observed (p < 0.001), 65% of patients (responders) had a reduction of > 15 points. Female patients had a significantly better response than male patients with a higher number of responders (76% vs. 38%; p < 0.001). Patients with a pain history < 1 year had a significantly better response than patients with a pain history > 1 year. The Physical Component Summary (PCS) increased from 36 ± 11 to 41 ± 11 (+ 18%, p < 0.001) and the Mental Component Summary (MCS) from 41 ± 7 to 43 ± 7 (+ 6%, p = 0.3). Overall sleep quality improved significantly from 4.6 ± 1.7 to 3.73 ± 1.7 points (p < 0.001), with a higher proportion of responders in the female group (37 vs. 18%; p < 0.034). No serious adverse events were observed during treatment.

CONCLUSIONS

Electrostatic therapy with Elosan Cabin C1 may be a useful and effective adjunct therapy for patients with chronic pain. The results suggest that female patients and those with a recent history of pain experience the greatest benefit.

TRIAL REGISTRATION

NCT04818294 (clinicaltrials.gov).

Central Sensitization and Pain: Pathophysiologic and Clinical Insights

Central sensitization is an increased responsiveness of nociceptive neurons in the central nervous system to their normal or subthreshold afferent input.

AIM

To explain how the notion of central sensitization has changed our understanding of pain conditions, discuss how this knowledge can be used to improve the management of pain, and highlight knowledge gaps that future research needs to address.

METHODS

Overview of definitions, assessment methods, and clinical implications.

RESULTS

Human pain models, and functional and molecular imaging have provided converging evidence that central sensitization occurs and is clinically relevant. Measures to assess central sensitization in patients are available; however, their ability to discriminate sensitization of central from peripheral neurons is unclear. Treatments that attenuate central sensitization are available, but the limited understanding of molecular and functional mechanisms hampers the development of target-specific treatments. The origin of central sensitization in human pain conditions that are not associated with tissue damage remains unclear.

CONCLUSION

The knowledge of central sensitization has revolutionized our neurobiological understanding of pain. Despite the limitations of clinical assessment in identifying central sensitization, it is appropriate to use the available tools to guide clinical decisions towards treatments that attenuate central sensitization. Future research that elucidates the causes, molecular and functional mechanisms of central sensitization would provide crucial progress towards the development of treatments that target specific mechanisms of central sensitization.

Effectiveness of different percutaneous electrolysis protocols in the endogenous modulation of pain: A Double-Blinded Randomized Clinical Trial

OBJECTIVE

This randomized clinical trial investigated if the application of percutaneous electrolysis (PE) enhances endogenous pain mechanisms (EPM) when compared with a simple needle application (acting as sham).

METHODS

Forty-six asymptomatic subjects, aged 18-40 years, were randomized into three groups receiving a single ultrasound-guided PE intervention consisting of a needle insertion on the lateral epicondyle: sham (without electrical current), low-intensity (0.3 mA, 90s), or high-intensity (three pulses of 3 mA, 3s) PE. Widespread pressure pain thresholds (PPT), conditioned pain modulation (CPM), and temporal summation (TS) were bilaterally assessed in the lateral epicondyle, bicipital groove, transverse process of C5 and tibialis anterior muscle. Outcomes were obtained by an assessor blinded to the treatment allocation of the subjects.

RESULTS

No significant changes in CPM were observed in either group (omnibus ANOVA all, P > .05). A significant bilateral increase in PPT in the lateral epicondyle in the high intensity group as compared with the sham group was observed (P < .01). A significant decrease of TS in both low (P = .002) and high (P = .049) intensity groups on the right, but not on the left, tibialis anterior was also observed when compared with the sham group.

CONCLUSIONS

One session of PE is able to slightly stimulate modulatory pathways related to nociceptive gain, particularly pressure pain sensitivity and temporal summation but not conditioning pain modulation, when compared with a sham needle intervention, with changes even contralaterally. No significant differences were found between low- and high-intensity doses of percutaneous electrolysis.

Precision management of post-COVID pain: An evidence and clinical-based approach

Background Pain after a SARS-CoV-2 acute infection (post-COVID pain) is becoming a new healthcare emergency but remains underestimated and most likely undertreated due to a lack of recognition of the phenomenon and knowledge of the underlying pain mechanisms. Evidence supporting any particular treatment approach for the management of post-COVID pain is lacking. Large variability in the patient response to any standard pain treatments is clinically observed, which has led to calls for a personalized, tailored approach to treating patients with chronic post-COVID pain (i.e. 'precision pain medicine'). Applying the global concerted action towards precision medicine to post-COVID pain could help guide clinical decision-making and aid in more effective treatments. Methods The current position paper discusses factors to be considered by clinicians for managing post-COVID pain ranging from identification of the pain phenotype to genetic consideration. Results The ability of clinicians to phenotype post-COVID pain into nociceptive, neuropathic, nociplastic or mixed type is suggested as the first step to better planification of a treatment programme. Further, the consideration of other factors, such as gender, comorbidities, treatments received at the acute phase of infection for onset-associated COVID-19 symptoms, factors during hospitalization or the presence of emotional disturbances should be implemented into a treatment programme. Conclusions Accordingly, considering these factors, management of post-COVID pain should include multimodal pharmacological and non-pharmacological modalities targeting emotional/cognitive aspects (i.e. psychological and/or coping strategies), central sensitization-associated mechanisms (i.e. pain neuroscience education), exercise programmes as well as lifestyle interventions (e.g. nutritional support and sleep management). SIGNIFICANCE: This position paper presents an evidence-based clinical reasoning approach for precision management of post-COVID pain.

Physiotherapy management of nociplastic pain: A Delphi study of Italian specialists

BACKGROUND AND PURPOSE

Nociplastic pain due to central sensitization (CS) is common in people suffering from chronic pain, but no clinical practice guideline is available in rehabilitative settings for patients' management. The aim of this study is to achieve expert consensus on physiotherapy competencies in the management of people with nociplastic pain and suspected CS mechanisms.

METHODS

A web-based Delphi process was employed. Experts in the rehabilitation field were recruited following pre-defined eligibility criteria. Following completion of three Delphi rounds, the final list of competencies was generated.

RESULTS

In all, 23 participants were recruited. They all completed Round 1 (23/23, 100%), twenty Round 2 and Round 3 (20/23, 87%). Following Round 1, seven areas were identified by the panel as crucial for CS physiotherapy management; 19 competencies out of 40 reached the consensus between experts, and nine additional competencies were added to Round 2 following literary review. Round 2 identified the agreement for all the 29 competencies. During Round 3, all the experts confirmed the final list generated through the consensus process.

DISCUSSION

An agreement between experts was found for the final list of competencies that a physiotherapist should implement every time it approaches people with suspected CS mechanisms. Further research is needed to support the clinical utility of our findings and their applicability in daily practice.

Effect of Transcutaneous Electrical Nerve Stimulation on Pain-related Quantitative Sensory Tests in Chronic Musculoskeletal Pain and Acute Experimental Pain: Systematic Review and Meta-analysis

This report provides a systematic review of the literature to analyze the effects of transcutaneous electrical nerve stimulation (TENS) on analgesia on sensitization measures, in studies with chronic musculoskeletal pain and in studies with acute experimental pain. The protocol was registered at PROSPERO (CRD42020213473). The authors searched Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature, EMBASE, Latin American and Caribbean Health Sciences Literature via Biblioteca Virtual de Saúde, Physiotherapy Evidence Database, PubMed, ScienceDirect, Web of Science, Google Scholar, and hand-searched reference lists were also conducted. Among 22,252 manuscripts found, 58 studies were included in the systematic review and 35 in the meta-analysis. Thirty-four studies assessed pain intensity; 24 studies investigated hyperalgesia; temporal summation was only evaluated in 2 studies; and conditioned pain modulation was not observed in the included studies. Meta-analyses favored TENS, despite its limitations and heterogeneity. Primary hyperalgesia in studies with musculoskeletal pain presented a high level of evidence, while other outcomes presented moderate evidence in the studies that were included. It is not possible to infer results about both temporal summation and conditioned pain modulation. Moderate evidence suggests that TENS promotes analgesia by reducing both central and peripheral sensitization, as shown by the reduction in primary and secondary hyperalgesia, pain intensity at rest, and during movement in experimental acute pain and chronic musculoskeletal pain. Overall, both types of studies analyzed in this review presented meta-analyses favorable to the use of TENS (compared to placebo TENS), showing reductions in both primary and secondary hyperalgesia, as well as decreases in pain intensity at rest and in motion. PERSPECTIVE: This article presents data from the literature on the effect of TENS through sensitization assessments in individuals with chronic musculoskeletal pain, or acute experimental pain. These data contribute to knowledge about pain neuroscience research, using TENS technology.

Central Sensitization in Cancer Survivors and Its Clinical Implications: State of the Art

Although the prevalence of cancer pain is 47% after treatment, cancer pain is often underestimated, and many patients are undertreated. The complexity of cancer pain contributes to the lack of its management. Recently, as the mechanism of cancer pain, it has become clear that central sensitization (CS) influences chronic pain conditions and the transition from acute to chronic pain. In this state-of-the-art review, we summarized the association of CS or central sensitivity syndrome with pain and the treatment for pain targeting CS in cancer survivors. The management of patients with CS should not only focus on tissue damage in either the affected body regions or within the central nervous system; rather, it should aim to target the underlying factors that sustain the CS process. Pain neuroscience education (PNE) is gaining popularity for managing chronic musculoskeletal pain and could be effective for pain and CS in breast cancer survivors. However, there is a study that did not demonstrate significant improvements after PNE, so further research is needed. Precision medicine involves the classification of patients into subgroups based on a multifaceted evaluation of disease and the implementation of treatment tailored to the characteristics of each patient, which may play a central role in the treatment of CS.

Manual Therapy Effects on Nonspecific Neck Pain Are Not Mediated by Mechanisms Related to Conditioned Pain Modulation: A Randomized Clinical Trial

BACKGROUND

Manual therapy (MT) is a treatment recommended by clinical practice guidelines in the management of patients with neck pain. However, the mechanisms through which MT works remain unknown. The aim of the present study is to investigate if MT is mediated by mechanisms related to conditioned pain modulation (CPM), comparing the effects of painful with a pain-free MT treatment.

METHODS

A two-arm, parallel, randomized controlled clinical trial with concealed allocation and blinding of the outcome assessor was conducted in university students with chronic or recurrent nonspecific neck pain (NSNP). Participants received either a painful or pain-free MT session. Psychophysical variables including pressure pain thresholds, CPM, temporal summation of pain and cold pain intensity were assessed before and immediately after treatment. In addition, changes in neck pain intensity over the following 7 days and self-perceived improvement immediately and 7 days after treatment were assessed.

RESULTS

No significant differences were found between groups in any of the psychophysical variables or in patients' self-perceived improvement. Only a significantly greater decrease in neck pain intensity immediately after treatment was found in the pain-free MT group compared to the painful MT group.

CONCLUSION

The results suggest that the immediate and short-term effects of MT on NSNP are not mediated by CPM-related mechanisms.

Effectiveness of a Manual Therapy Protocol in Women with Pelvic Pain Due to Endometriosis: A Randomized Clinical Trial

A randomized controlled trial was carried out to assess the effectiveness of a manual therapy protocol in terms of the clinical characteristics, quality of life, and emotional condition of the women with endometriosis-related pelvic pain. Forty-one women (mean age of 36.10 (6.97) years) with pelvic pain due to endometriosis were randomly divided into (i) a manual therapy group (MTG) (n = 21) and (ii) a placebo group (PG) (n = 20). Both groups received an 8-week intervention. Pain, lumbar mobility, endometriosis health profile, quality of life, depression and anxiety levels, and the patient's perception of change were assessed before (T0) and after (T1) the intervention, as well as at a one-month follow-up (T2) and a six-month follow-up (T3). The MTG significantly improved pain intensity, powerlessness, lumbar mobility, and physical quality of life at T1 (p < 0.05). The results were maintained for pain intensity at T2 and T3. In addition, both the MTG and PG improved emotional wellbeing at T1 (p < 0.05). Neither group improved in terms of social support, self-image, and depression and anxiety levels after the intervention (p > 0.05). In conclusion, manual therapy may be an excellent complement to the gynecological treatment of endometriosis-related pelvic pain by alleviating pain and improving women's endometriosis health profile and physical quality of life.

Terminally ill patients' and their relatives' experiences and behaviors regarding complementary and alternative medicine utilization in hospice palliative inpatient care units: a cross-sectional, multicenter survey

BACKGROUND

Terminally ill patients often experience exacerbations of diseases that render mainstream medicine ineffective in relieving symptoms, prompting attempts at complementary and alternative medicine (CAM). This study collected data from terminally ill patients and their relatives to determine differences between CAM use, behavioral patterns, and perceptions of health information about CAM.

METHODS

A cross-sectional design using a self-administered questionnaire was adopted. Eight medical institutions in Taiwan with inpatient hospice palliative care units were chosen. Ninety-two terminally ill patients and 267 relatives met the inclusion criteria. The questions concerned the experience of CAM use, the kinds of products/services CAM provided, the purpose of CAM use, the source of CAM information, and the perceptions and attitudes toward CAM.

RESULTS

Both terminally ill patients and their relatives have a high proportion of lifetime and one-year prevalence of CAM use (88.0% vs. 88.4%; p = 0.929). CAM use for musculoskeletal and neurological discomfort is higher among terminally ill patients than among their relatives. Relatives/friends are the most frequent sources of information on CAM (53.3% vs. 62.2%; p = 0.133). The percentage of terminally ill patients who discontinued mainstream medical treatment because of CAM use was higher than that of their relatives (18.5% vs. 9.3%; p = 0.026). More than half the terminally ill patients and their relatives had never been asked about CAM by medical staff (64.1% vs. 66.7%), nor had they informed medical professionals about the use of CAM products and services (63% vs. 66.9%). Random inquiries by medical professionals may be associated with increased disclosure of CAM use (terminally ill patients: odds ratio, 9.75; 95% confidence interval, 1.97-48.35 vs. relatives: odds ratio, 5.61; 95% confidence interval, 2.66-11.83).

CONCLUSIONS

The high prevalence and concealment of CAM use in terminally ill patients should be considered. Medical professionals should establish a friendly and barrier-free communication model, encourage patients to share CAM experiences, and provide evidence-based information on the use of CAM products and services, to reduce the potential damage caused by harmful use.

Immediate Effects of Dry Needling on Central Pain Processing and Skin Conductance in Patients with Chronic Nonspecific Neck Pain: A Randomized Controlled Trial

Although current evidence supports the use of dry needling for improving some clinical outcomes in people with neck pain, no previous research explored the effects of dry needling on the central processing of pain and autonomic nervous system in this population. Therefore, this clinical trial aimed to compare the effects of real and sham dry needling on autonomic nervous system function, pain processing as well as clinical and psychological variables in patients with chronic nonspecific neck pain. A double-blinded randomized clinical trial including 60 patients with neck pain was conducted. Patients were randomized to the real needling (n = 30) or sham needling (n = 30) group. Skin conductance (SC), pressure pain thresholds (PPTs), temporal summation (TS), conditioned pain modulation (CPM) as well as pain intensity, related-disability, catastrophism, and kinesiophobia levels were assessed by an assessor blinded to the allocation intervention. The results did not find significant group * time interactions for most outcomes, except for the global percentage of change of SC values (mean: F = 35.90, p < 0.001, ηp2 = 0.459; minimum: F = 33.99, p = 0.839, ηp2 = 0.371; maximum: F = 24.71, p < 0.001, ηp2 = 0.037) and PPTs at C5-C6 joint in the same side of needling (F = 9.982; p = 0.003; = 0.147), in favor of the dry needling group. Although the proportion of subjects experiencing moderate to large self-perceived improvement after the intervention was significantly higher (X2 = 8.297; p = 0.004) within the dry needling group (n = 18, 60%) than in the sham needling group (n = 7, 23.3%), both groups experienced similar improvements in clinical and psychological variables. Our results suggested that dry needling applied to patients with chronic nonspecific neck pain produced an immediate decrease in mechanical hyperalgesia at local sites and produced an increase in skin conductance as compared with sham needling. No changes in central pain processing were observed. A single session of sham or real dry needling was similarly effective for decreasing related disability, pain intensity, catastrophism, and kinesiophobia levels. Further studies are needed to better understand the clinical implications of autonomic nervous system activation on central sensitization and pain processing in the long-term after the application of dry needling.

Neuroendocrine effects of a single bout of functional and core stabilization training in women with chronic nonspecific low back pain: A crossover study

Exercise-induced hypoalgesia (EIH) is characterized as the pain reduction after an exercise session and it seems to be related to the release of plasma β-endorphin. In this sense, the core stabilization training (CT) has been suggested for patients with chronic nonspecific low back pain (CNSLBP), but it is unclear whether it induces EIH. Patients with CNSLBP have neuromotor dysfunctions that can affect the performance of functional tasks, thus, performing functional training (FT) could improve motor control and promote EIH, since functional training uses multi-joint exercises that aim to improve the functionality of actions performed in daily life. EIH is usually assessed using quantitative sensory tests (QST) such as conditioned pain modulation, pressure pain threshold, and temporal summation. Thus, the sum of parameters from quantitative sensory tests and plasma β-endorphin would make it possible to understand what the neuroendocrine effects of FT and CT session are. Our study compared the acute effect of CT and FT on the EIH and plasma β-endorphin release, and correlated plasma β-endorphin with quantitative sensory testing in patients with CNSLBP. Eighteen women performed two training sessions (CT and FT) with an interval of 48 h between sessions. EIH was assessed by QST and plasma β-endorphin levels. Results showed that only FT significantly increased plasma β-endorphin (FT p < 0.01; CT p = 0.45), which correlated with pain pressure threshold (PPT) and conditioned pain modulation (CPM). However, QST values were not different in women with CNSLBP after CT or FT protocols. Plasma β-endorphin correlated with PPT and CPM, however, the same did not occur with a temporal summation.

Investigating the effects of mobilization with movement and exercise on pain modulation processes in shoulder pain - a single cohort pilot study with short-term follow up

OBJECTIVE

To explore the association between manual therapy and exercise and pain modulation and clinical characteristics in people with musculoskeletal shoulder pain.

METHODS

This is a prospective, longitudinal, single cohort pilot study. People with shoulder pain for longer than 6 weeks underwent 4 weeks of glenohumeral mobilization with movement and shoulder exercises. Measures of pain modulation, shoulder pain, disability, range of motion and psychosocial factors were assessed at baseline and immediately after the 4-week period of treatment. Treatment effectiveness was assessed through parametric, non-parametric and multilevel modeling statistics.

RESULTS

Twenty-three individuals participatedwith no loss to follow-up. Significant and meaningful improvements in shoulder pain (NRS mean change 1.6/10, 95% CI 0.4 to 2.7), disability (SPADI mean change 20.5/100, 95% CI 13.1 to 27.9) and range of motion (mean change 33°, 95% CI 23 to 43°) were observed following treatment. Statistical but non-clinically meaningful changes were observed in temporal summation of pain (mean change 0.3/10, 95% CI 0.1 to 0.4) and anxiety (mean change 0.86/21, 95% CI 0.18 to 1.55). Significant reductions were observed in temporal summation of pain (mean change 0.3/10, 95% CI 0.1 to 0.4) and anxiety (mean change 0.86/21, 95% CI 0.18 to 1.55), however these were not considered clinically important. No association was found between clinical characteristics and sensory measures. No association was found between clinical characteristics and sensory measures.

CONCLUSION

Glenohumeral mobilization with movement and exercise did not improve pain modulation, despite improvements in pain, function and range of motion, in people with shoulder pain.

Radial shock-wave therapy for frozen shoulder patients with type 2 diabetes mellitus: a pilot trial comparing two different energy levels

BACKGROUND

Extracorporeal shock-wave therapy (ESWT) is highly recommended for the management of orthopedic shoulder pathologies. Yet, the clinical relevance of the dose difference effect of radial ESWT approaches in the management of frozen shoulder patients with type 2 diabetes mellitus remains uncertain.

AIM

The aim was to examine the short-term effects of medium-and high-energy levels of radial ESWT (rESWT) in the treatment of frozen shoulder patients with type 2 diabetes mellitus.

DESIGN

Prospective clinical pilot study.

SETTING

This study was conducted in an outpatient clinic.

POPULATION

Thirty-nine patients who had frozen shoulder untreated for at least 3 months, diagnosed with type 2 diabetes mellitus for ≥3 years were included.

METHODS

The patients were randomly allocated to receive either high-energy rESWT (hrESWT), or medium-energy rESWT (mrESWT) or placebo at 8 Hz twice a week for six weeks. The primary outcome measure was pain, evaluated by the Visual Analog Scale (VAS) Score. Secondary outcome measures were function evaluated by the Shoulder Pain and Disability Index (SPADI) Score, and shoulder active range of motion (AROM). The mechanical properties of the deltoid and trapezius muscles were assessed using the MyotonPRO (Myoton AS, Tallinn, Estonia).

RESULTS

The mrESWT resulted in statistically significant reductions in night pain at 6 weeks (η<inf>p</inf>²=0.27, P=0.003). Significantly improved function (SPADI scores: -35.42±21.29 vs.-29.59±22.60; η<inf>p</inf>²=0.39, P˂0.001) was found in both hrESWT and mrESWT group by 6 weeks. Significantly higher mean shoulder AROM values were recorded for external rotation (η<inf>p</inf>²=0.53, P<0.001), and internal rotation (η<inf>p</inf>²=0.21, P=0.020), in the hrESWT group at the 6^th week. A significantly improved resting tone (η<inf>p</inf>²=0.58) and stiffness of deltoid muscle (η<inf>p</inf>²=0.62) were found in the mrESWT group (P<0.001). The trapezius muscle resting tone reduced with hrESWT (η<inf>p</inf>²=0.17, P=0.033).

CONCLUSIONS

Regardless of the energy levels, rESWT appears to be an effective therapeutic intervention for frozen shoulder patients with type 2 diabetes mellitus in the short-term results.

CLINICAL REHABILITATION IMPACT

Our results suggest that this rESWT can be a useful strategy for the rehabilitation of frozen shoulder patients with type 2 diabetes mellitus. This is the first study on dose difference effectiveness in terms of the clinical significance of rESWT which is key to transfer research evidence into practice.

[Pain modulation through exercise : Exercise-induced hypoalgesia in physiotherapy]

Exercise prescription is a central tenet of physiotherapy. One of the numerous benefits of exercise is its influence on endogenous pain modulation. Exercise-induced hypoalgesia (EIH) refers to a short-term change in pain sensitivity following an acute bout of exercise. Interest in this phenomenon has grown considerably with over 150 articles published, including four systematic reviews in 2020 alone.This narrative review provides an overview of EIH including a definition and summary of the underlying mechanisms and mediating factors. Recent systematic reviews assessing EIH in people with and without musculoskeletal complaints were evaluated using AMSTAR2. Review findings confirm the presence of EIH. For asymptomatic people, confidence in the evidence was low to very low due to high heterogeneity of included studies, risk of bias, and study eligibility. For people with pain, there is very low confidence, at best, that subgroups or isometric exercise show altered EIH. Despite the growing body of evidence, challenges within the available evidence due to its complex nature are highlighted. Recommendations regarding outcome measures and exercise parameters are required, and further understanding of reliability and validity of EIH is needed. There is a demand to further elucidate these parameters and contextual factors to advance our understanding of EIH. Additional clinical research, especially in patient populations, is required to then provide implications for rehabilitation.

Segmental Chiropractic Spinal Manipulation Does not Reduce Pain Amplification and the Associated Pain-Related Brain Activity in a Capsaicin-Heat Pain Model

Musculoskeletal injuries lead to sensitization of nociceptors and primary hyperalgesia (hypersensitivity to painful stimuli). This occurs with back injuries, which are associated with acute pain and increased pain sensitivity at the site of injury. In some cases, back pain persists and leads to central sensitization and chronic pain. Thus, reducing primary hyperalgesia to prevent central sensitization may limit the transition from acute to chronic back pain. It has been shown that spinal manipulation (SM) reduces experimental and clinical pain, but the effect of SM on primary hyperalgesia and hypersensitivity to painful stimuli remains unclear. The goal of the present study was to investigate the effect of SM on pain hypersensitivity using a capsaicin-heat pain model. Laser stimulation was used to evoke heat pain and the associated brain activity, which were measured to assess their modulation by SM. Eighty healthy participants were recruited and randomly assigned to one of the four experimental groups: inert cream and no intervention; capsaicin cream and no intervention; capsaicin cream and SM at T7; capsaicin cream and placebo. Inert or capsaicin cream (1%) was applied to the T9 area. SM or placebo were performed 25 min after cream application. A series of laser stimuli were delivered on the area of cream application (1) before cream application, (2) after cream application but before SM or placebo, and (3) after SM or placebo. Capsaicin cream induced a significant increase in laser pain (p &lt; 0.001) and laser-evoked potential amplitude (p &lt; 0.001). However, SM did not decrease the amplification of laser pain or laser-evoked potentials by capsaicin. These results indicate that segmental SM does not reduce pain hypersensitivity and the associated pain-related brain activity in a capsaicin-heat pain model.

Central sensitisation in chronic pain conditions: latest discoveries and their potential for precision medicine

Chronic pain is a leading cause of disability globally and associated with enormous health-care costs. The discrepancy between the extent of tissue damage and the magnitude of pain, disability, and associated symptoms represents a diagnostic challenge for rheumatology specialists. Central sensitisation, defined as an amplification of neural signalling within the CNS that elicits pain hypersensitivity, has been investigated as a reason for this discrepancy. Features of central sensitisation have been documented in various pain conditions common in rheumatology practice, including fibromyalgia, osteoarthritis, rheumatoid arthritis, Ehlers-Danlos syndrome, upper extremity tendinopathies, headache, and spinal pain. Within individual pain conditions, there is substantial variation among patients in terms of presence and magnitude of central sensitisation, stressing the importance of individual assessment. Central sensitisation predicts poor treatment outcomes in multiple patient populations. The available evidence supports various pharmacological and non-pharmacological strategies to reduce central sensitisation and to improve patient outcomes in several conditions commonly seen in rheumatology practice. These data open up new treatment perspectives, with the possibility for precision pain medicine treatment according to pain phenotyping as a logical next step. With this view, studies suggest the possibility of matching non-pharmacological approaches, or medications, or both to the central sensitisation pain phenotypes.

A COVID-19 Rehabilitation Prospective Surveillance Model for Use by Physiotherapists

The long-term sequelae of coronavirus disease 2019 (COVID-19) are only now beginning to be defined, but it is already known that the disease can have direct and indirect impacts mainly on the cardiorespiratory and neuromuscular systems and may affect mental health. A role for rehabilitation professionals from all disciplines in addressing COVID-19 sequelae is recognised, but it is essential that patient assessment be systematic if health complications are to be identified and treated and, if possible, prevented. The aim is to present a COVID-19 prospective surveillance model based on sensitive and easily used assessment tools, which is urgently required. Following the Oxford Centre for Evidence-Based Medicine Level of Evidence Tool, an expert team in cardiorespiratory, neuromuscular and mental health worked via telemeetings to establish a model that provides guidelines to rehabilitation professionals working with patients who require rehabilitation after suffering from COVID-19. A COVID-19 prospective surveillance model is proposed for use by rehabilitation professionals and includes both face-to-face and telematic monitoring components. This model should facilitate the early identification and management of long-term COVID-19 sequelae, thus responding to an arising need.

Pain sensitivity is reduced by exercise training: Evidence from a systematic review and meta-analysis

BELAVY, D. L., J. Van Oosterwijck, M. Clarkson, E. Dhondt, N. L. Mundell, C. Miller and P. J. Owen. NEUROSCI BIOBEHAV REV 21(1) XXX-XXX, 2020. Exercise training is capable of reducing pain in chronic pain syndromes, yet its mechanisms are less well established. One mechanism may be via the impact of exercise on increasing a person's pain threshold. Here we show, via meta-analysis of fifteen exercise training studies in pain syndromes that exercise training leads to increased pressure pain thresholds (low to moderate quality evidence). We also find low to moderate quality evidence exists that exercise training was more effective than non-exercise interventions, such as pain education, massage and stress management for improving pain sensitivity. Further, the effect of exercise was greater locally at the site of pain and less so at remote regions. These finding suggest that adaptations in central inhibition occur over time with exercise training and, more widely, add to the mechanistic understanding of how effective interventions can improve pain in chronic pain syndromes.

Clinical Reasoning for the Examination and Physical Therapy Treatment of Temporomandibular Disorders (TMD): A Narrative Literature Review

The current narrative literature review aims to discuss clinical reasoning based on nociceptive pain mechanisms for determining the most appropriate assessment and therapeutic strategy and to identify/map the most updated scientific evidence in relation to physical therapy interventions for patients with temporomandibular disorders (TMDs). We will also propose an algorithm for clinical examination and treatment decisions and a pain model integrating current knowledge of pain neuroscience. The clinical examination of patients with TMDs should be based on nociceptive mechanisms and include the potential identification of the dominant, central, or peripheral sensitization driver. Additionally, the musculoskeletal drivers of these sensitization processes should be assessed with the aim of reproducing symptoms. Therapeutic strategies applied for managing TMDs can be grouped into tissue-based impairment treatments (bottom-up interventions) and strategies targeting the central nervous system (top-down interventions). Bottom-up strategies include joint-, soft tissue-, and nerve-targeting interventions, as well as needling therapies, whereas top-down strategies include exercises, grade motor imagery, and also pain neuroscience education. Evidence shows that the effectiveness of these interventions depends on the clinical reasoning applied, since not all strategies are equally effective for the different TMD subgroups. In fact, the presence or absence of a central sensitization driver could lead to different treatment outcomes. It seems that multimodal approaches are more effective and should be applied in patients with TMDs. The current paper also proposes a clinical decision algorithm integrating clinical diagnosis with nociceptive mechanisms for the application of the most appropriate treatment approach.

The clinical decision making process in the use of mobilisation with movement - A Delphi survey

BACKGROUND

Mobilisation with movement (MWM) is a method of treating musculoskeletal disorders. Although widely used clinically and with increasing research investigation, little is known about the decision making process for its utilization.

OBJECTIVES

To understand the factors experts believe important for utilization of MWM when assessing a patient, predicting responses to its delivery, responsive body areas, and expected outcomes to MWM.

DESIGN

A web-based Delphi study of experts in the use of MWM.

METHODS

Round one contained five open-ended questions regarding assessment strategies, prediction of successful and unsuccessful outcomes, body areas most responsive, and common outcome measures observed. Rounds 2 and 3 were quantitative and aimed at establishing consensus.

RESULTS

Thirty seven experts participated in the study and took part in round 1, thirty two in round 2, and twenty eight in round 3. The exclusion of red flags and impairment in range of motion (ROM), obtained the highest level of consensus for the item assessment strategies. Patient's presenting with a variety of issues on movement, in addition to mild to moderate levels of severity and immediately responsive to a trial MWM, were believed to respond favourably to MWM. Patients with predominant inflammatory pain, with high levels of psychosocial factors, increased central sensitization and not improving after a trial of MWM, were recognized as non-responders. Improvement of different aspects of movement (e.g. ROM, less fear) are the most common outcomes observed.

CONCLUSIONS

This study provides factors believed to be important in the decision making process when using MWM clinically.