Prevalence of and referred pain from myofascial trigger points in the forearm muscles in patients with lateral epicondylalgia

MyofAPPcial: Construct validity of a novel technological aid for improving clinical reasoning in the management of myofascial pain syndrome

BACKGROUND

Physiotherapists encounter challenges in diagnosing myofascial trigger points (MTrPs), which are crucial for managing myofascial pain but difficult due to their complex referred pain patterns. We aimed to assess if an interactive software (MyofAPPcial) can enhance the ability of physical therapists specialized in musculoskeletal disorders (as clinicians and as researchers and educators) to identify referred pain patterns associated with specific MTrPs and to explore their opinion about incorporating this technology regularly into their professional setting.

METHODS

After developing the app, a descriptive cross-sectional survey study was conducted. Participants were asked about their demographic characteristics, professional experience, two knowledge tests (first without and later with MyofAPPcial support) and the 18-item mHealth app usability questionnaire.

RESULTS

Fifty-nine participants completed the survey (47.5% clinicians and 62.5% researchers/educators). Groups were comparable in terms of age, gender and professional experience (p > .05). However, clinicians coursed shorter specific MPS trainings (p = .007) and handle more cases a week (p < .001). In the first knowledge test, participants in both the groups were more accurate in identifying pain maps of highly prevalent MTrPs than those with a moderate or low prevalence (p < .001), with no differences between the groups for individual items (all, p > .05) nor the total score (p > .05). In the second knowledge test, perfect scores were obtained for all items in both the groups. Finally, MyofAPPcial scored high satisfaction and app usefulness, with no difference between clinicians and researchers/educators (except greater convenience of use for researchers/educators p = .02).

CONCLUSIONS

MyofAPPcial enhances physiotherapists' ability to accurately identify MTrPs, with a good acceptation among clinicians and researchers/educators.

Lateral elbow magnetic resonance imaging findings in patients without pain complaints

Magnetic resonance imaging (MRI) can help evaluate lateral epicondylitis; however, abnormal findings on MRI are not always consistent with the symptoms. The occurrence of such abnormal MRI findings at the lateral side of the elbow in patients without pain remains unclear. Therefore, the purpose of this study was to investigate the MRI findings of the lateral elbow joint in patients with no complaints of pain in the elbow joint. We retrospectively identified 152 patients who had undergone MRI of the area including the elbow from July 2015 to January 2022. We excluded patients with pain in the elbow area and those with diagnosis of diseases that could affect MRI findings at the lateral elbow. The presence of lateral collateral ligament complex (LCLC) and common extensor tendon (CET) lesions on MRI was assessed by two reviewers. In total, 22 patients (12 men and 10 women) were included in the analysis. The mean age of the patients was 54 years. Five patients, all ≥65 years old, had abnormal findings related to the LCLC or CET on MRI. Abnormal LCLC and CET findings on MRI can be encountered in older patients even in the absence of elbow pain.

Efficacy of Myofascial Release With Transcutaneous Electrical Nerve Stimulation Conductive Glove for Neck Myofascial Syndrome: A Randomized Clinical Trial Study

OBJECTIVE

The purpose of this study was to assess the efficacy of a myofascial release (MR) protocol applied with a transcutaneous electrical nerve stimulation (TENS) conductive glove.

METHODS

Eighty individuals with neck myofascial syndrome were randomly divided into 4 groups: (1) MR protocol with a TENS conductive glove (MR+TENS), (2) MR protocol without TENS (MR), (3) conventional TENS protocol (TENS), and (4) placebo TENS (control). All participants attended 6 sessions over a period of 3 weeks. The following measures were evaluated at baseline, at the third week, and at the 1-month follow-up: Pain with the visual analog scale (VAS pain), upper trapezius pressure pain threshold (PPT) with pressure algometry, cervical range of motion (ROM) with goniometry, and disability with the neck disability index (NDI). A 2-way ANOVA with repeated measurements was applied.

RESULTS

Significant changes between the 3 intervention groups and the control group were noted in the VAS and the NDI scores (P < .05) with the MR+TENS group exhibiting the biggest difference. Additionally, MR significantly increased PPT compared to TENS, and even further when applied with the conductive glove (P < .05). Regarding lateral flexion ROM, MR was equally effective either alone or in combination with the glove compared to TENS (P < .05). In contrast, TENS did not appear to affect neck PPT and ROM (P > .05). Finally, no difference between the groups was detected in cervical rotation ROM (P > .05).

CONCLUSION

The MR protocol appears to be more effective in dealing with pain, disability, and lateral flexion ROM than conventional TENS. A TENS conductive glove significantly improves the effects of MR, possibly due to the combined mechanical and electrical stimulation of the muscle.

Exploring Symptom Responses to Upper Limb Neural Test Variations of the Radial Nerve in Patients With Lateral Epicondylalgia: An Observational Study

OBJECTIVE

Clinical practice guidelines recommend the radial nerve mechanosensitivity evaluation in patients with lateral epicondylalgia. Despite different positions and sequences having been described, no research analyzed how each variation triggers symptoms associated with lateral epicondylalgia. The aim of this study was to explore the effects of different positions and sequences in the upper limb neural tension test 2b (ULNT2b) in symptom responses in patients with lateral epicondylalgia.

METHODS

In this observational study, 66 patients underwent 4 test conditions: standard ULNT2b, ULNT2b proximal to distal, ULNT2B with resisted supination, and resisted supination isolated. Paresthesia sensations, symptom reproduction, pain intensity (measured using a visual analog scale), and distribution of painful symptoms data were collected.

RESULTS

Significant differences in paresthesia sensations were observed between groups, with significant differences between the standard ULNT2B and other ULNT variations or resisted supination maneuvers. Symptom reproduction also differed significantly across groups, with significant differences between the standard ULNT2B and other ULNT or resisted supination tests. The positive/negative test and percentage of distribution of painful symptoms scores varied significantly across 4 conditions in both lateral and frontal views. Although pain intensity scores during tests were comparable among the tests, distribution of painful symptoms differed significantly.

CONCLUSION

Variations in the ULNT2b test can affect symptom responses in patients with lateral epicondylalgia. The standard ULNT2b test appears more effective at reproducing symptoms, intensity of paresthesia, and distribution of painful symptoms compared to other ULNT variations and the resisted supination test.

IMPACT

ULNT2b sequences have been shown to elicit varying responses concerning paresthesia, replication of familiar symptoms, positive/negative test results, and distribution of painful symptoms. Clinicians should consider specific test variations during the patients' radial nerve mechanosensitivity assessment to identify aggravating factors reproducing recognizable symptoms. A control group of asymptomatic participants and the role of presence of other comorbidities, psychological factors, or the duration of symptoms were not considered in this study and might play an important role influencing the results of the tests.

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.

Cardiovascular Disease Risk Factors Predict the Development and Numbers of Common Musculoskeletal Disorders in a Prospective Cohort

OBJECTIVE

The aim of the study is to assess risk of common musculoskeletal disorders (MSDs) based on cardiovascular disease (CVD) risk scores.

METHODS

Data from a 9-year prospective cohort of 1224 workers in three states were analyzed. Baseline data included questionnaires, structured interviews, physical examinations, anthropometric measurements, nerve conduction studies, and individualized measurement of job physical factors. Monthly follow-ups were conducted. Framingham risk scores were calculated. A priori case definitions were constructed for carpal tunnel syndrome, lateral epicondylopathy, medial epicondylopathy, and rotator cuff tendinopathy.

RESULTS

Adjusted RRs for one or more MSDs increased to 3.90 (95% confidence interval, 2.20-6.90) among those with 10-year cardiovascular disease risk scores greater than 15% and 17.4 (95% confidence interval, 3.85-78.62) among those with more than 4 disorders.

CONCLUSIONS

Cardiovascular disease factors are strongly associated with the subsequent development of common MSDs. Risks among those with multiple MSDs are considerably stronger.

Myofascial Pain Syndrome: A Nociceptive Condition Comorbid with Neuropathic or Nociplastic Pain

Myofascial pain syndrome is featured by the presence of myofascial trigger points (TrPs). Whether TrPs are primary or secondary phenomena or if they relate to central or peripheral nervous system disorders is controversial. Referred pain, a cardinal sign of TrPs, is a central phenomenon driven by peripheral input. In 2021, the International Association for the Study of Pain (IASP) proposed a clinical criteria and grading system for classifying patients with pain on nociceptive, neuropathic, or nociplastic phenotypes. Myofascial TrP pain has been traditionally categorized as a nociceptive phenotype; however, increasing evidence supports that this condition could be present in patients with predominantly nociplastic pain, particularly when it is associated with an underlying medical condition. The clinical response of some therapeutic approaches for managing TrPs remains unclear. Accordingly, the ability to classify myofascial TrP pain into one of these phenotypes would likely be critical for producing more successful clinical treatment outcomes by a precision medicine approach. This consensus paper presents evidence supporting the possibility of subgrouping individuals with myofascial TrP pain into nociceptive, nociplastic, or mixed-type phenotype. It is concluded that myofascial pain caused by TrPs is primarily a nociceptive pain condition, is unlikely to be classified as neuropathic or nociplastic, but can be present in patients with predominantly neuropathic or nociplastic pain. In the latter cases, management of the predominant central pain problem should be a major treatment goal, but the peripheral drive from TrPs should not be ignored, since TrP treatment has been shown to reduce sensitization-associated symptomatology in nociplastic pain conditions, e.g., fibromyalgia.

Myofascial Pain Syndrome in Women with Primary Dysmenorrhea: A Case-Control Study

There is limited information on myofascial trigger points (MTrPs) and specific symptoms of chronic pelvic pain and, more specifically, dysmenorrhea. The objective of this study was to determine whether patients suffering from primary dysmenorrhea present alterations in mechanosensitivity and pain patterns, and greater presence of MTrPs in the abdominal and pelvic floor muscles. A case-control study was carried out with a total sample of 84 participants distributed based on primary dysmenorrhea and contraceptive treatment. The sample was divided into four groups each comprising 21 women. Data on pain, quality of life, and productivity and work absenteeism were collected; three assessments were made in different phases of the menstrual cycle, to report data on pressure pain threshold, MTrP presence, and referred pain areas. One-way ANOVA tests showed statistically significant differences (p < 0.01) between the groups, for the Physical Health domain and the total score of the SF-12 questionnaire, and for all the domains of the McGill questionnaire; but no significant differences were found in the data from the WPAI-GH questionnaire. Statistically significant data (p < 0.01) were found for mechanosensitivity in the abdominal area and limbs, but not for the lumbar assessment, within the group, with very few significant intergroup differences. The frequency of active MTrPs is higher in the groups of women with primary dysmenorrhea and during the menstrual phase, with the prevalence of myofascial trigger points of the iliococcygeus muscle being especially high in all examination groups (>50%) and higher than 70% in women with primary dysmenorrhea, in the menstrual phase, and the internal obturator muscle (100%) in the menstrual phase. Referred pain areas of the pelvic floor muscles increase in women with primary dysmenorrhea.

Analyzing the Interaction between Clinical, Neurophysiological and Psychological Outcomes Underlying Chronic Plantar Heel Pain: A Network Analysis Study

Plantar heel pain (PHP) is one of the most common foot pain conditions in adults. Several biological and psychological factors could be involved in chronic PHP in a complex matrix. However, reciprocal interactions between these factors are unknown. The aim of the present study was to use network analysis to quantify potential multivariate relationships between pain-related, function, clinical, mechanosensitivity, psychological, and health-related variables in individuals with PHP. Demographic (age, gender), pain-related (pain intensity), function, clinical (myofascial trigger points [TrPs]), mechanosensitivity (pressure pain thresholds), psychological (Beck Depression Inventory), and health-related variables (EQ-5D-5L) were collected in 81 PHP patients. Network connectivity analysis was conducted to quantify the adjusted correlations between the modeled variables and to assess their centrality indices. The connectivity network showed local associations between pain-related variables, foot function, and mechanosensitivity. Additionally, associations between quality of life, depression, and pain-related variables were found, while TrPs was associated with quality of life and mechanosensitivity. The node with the highest strength centrality was the worst pain intensity, while mechanosensitivity and worst pain intensity showed the highest closeness and betweenness centrality. This is the first study to apply network modeling to understand the connections between pain-related, function, clinical, mechanosensitivity, psychological, and health-related variables in PHP. The role of pain severity and mechanosensitivity is highlighted and supported by the network. Thus, this study reveals potential factors that could be the target in the management of PHP, promoting a comprehensive and effective therapeutic approach.

Altered Brain Activity and Effective Connectivity within the Nonsensory Cortex during Stimulation of a Latent Myofascial Trigger Point

Myofascial trigger point (MTrP), an iconic characteristic of myofascial pain syndrome (MPS), can induce cerebral cortex changes including altered cortical excitability and connectivity. The corresponding characteristically reactive cortex is still ambiguous. Seventeen participants with latent MTrPs underwent functional near-infrared spectroscopy (fNIRS) to collect cerebral oxygenation hemoglobin (Δ[oxy-Hb]) signals. The Δ[oxy-Hb] signals of the left/right prefrontal cortex (L/R PFC), left/right motor cortex (L/R MC), and left/right occipital lobe (L/R OL) of the subjects were measured using functional near-infrared spectroscopy (fNIRS) in the resting state, nonmyofascial trigger point (NMTrP), state and MTrP state. The data investigated the latent MTrP-induced changes in brain activity and effective connectivity (EC) within the nonsensory cortex. The parameter wavelet amplitude (WA) was used to describe cortical activation, EC to show brain network connectivity, and main coupling direction (mCD) to exhibit the dominant connectivity direction in different frequency bands. An increasing trend of WA and a decreasing trend of EC values were observed in the PFC. The interregional mCD was primarily shifted from a unidirectional to bidirectional connection, especially from PFC to MC or OL, when responding to manual stimulation during the MTrP state compared with resting state and NMTrP state in the intervals III, IV, and V. This study demonstrates that the nonsensory cortex PFC, MC, and OL can participate in the cortical reactions induced by stimulation of a latent MTrP. Additionally, the PFC shows nonnegligible higher activation and weakened regulation than other brain regions. Thus, the PFC may be responsible for the central cortical regulation of a latent MTrP. This trial is registered with ChiCTR2100048433.

Japanese Orthopaedic Association (JOA) clinical practice guidelines on the management of lateral epicondylitis of the humerus - Secondary publication

BACKGROUND

The guidelines presented herein provide recommendations for the management of patients with lateral epicondylitis of the humerus. These recommendations are endorsed by the Japanese Orthopaedic Association (JOA) and Japan Elbow Society.

METHODS

The JOA lateral epicondylitis guideline committee revised the previous guidelines on the basis of the "Medical Information Network Distribution Service Handbook for Clinical Practice Guideline Development 2014", which emphasized the importance of the balance between benefit and harm, and proposed a desirable method for preparing clinical guidelines in Japan. These guidelines consist of 11 clinical questions (CQs), 9 background questions (BQs), and 3 future research questions (FRQs). For each CQ, outcomes from the literature were collected and evaluated systematically according to the adopted study design.

RESULTS

The committee proposed recommendations for each CQ by determining the level of evidence and assessing the consensus rate. Physical therapy was the best recommendation with the best evidence. The BQs and FRQs were answered by collecting evidence based on the literature.

CONCLUSIONS

The guidelines presented herein were reviewed systematically, and recommendations were proposed for each CQ. These guidelines are expected to be widely used not only by surgeons or physicians but also by other healthcare providers, such as nurses, therapists, and athletic trainers.

Efficacy of Fu's Subcutaneous Needling on Myofascial Trigger Points for Lateral Epicondylalgia: A Randomized Control Trial

Lateral epicondylalgia (LE), a common overuse syndrome of the extensor muscle and tendons on the lateral epicondyle, causes persistent severe musculoskeletal pain on the outer part of the elbow. Fu's subcutaneous needling (FSN), a newly invented subtype of acupuncture and dry needling, is a new trend and potential treatment of LE by targeting the myofascial trigger points (MTrPs). However, no scientific evidence is available to support this method. This study aims to evaluate the distal FSN treatment on the LE by measuring pain-related scales, such as visual analog scale (VAS), pressure pain threshold (PPT), muscle tissue hardness (TH), pain-free grip (PFG), and the functional outcome by a patient-rated tennis elbow evaluation (PRTEE) questionnaire study. A total of 60 LE patients were randomly divided into FSN (n = 30) and transcutaneous electrical nerve stimulation (TENS, n = 30) as the control group. Every subject was treated with three regimens and followed up for 15 days. Results showed that FSN has an immediate effect on VAS, PPT, TH, and PFG. Moreover, sustained effects on pain relief were followed up to 15 days. Pain remission was consistent with long-term PRTEE results. Overall, FSN is a safe and efficient therapy option for LE, significantly improving pain relief and activity difficulty with immediate, short-term, and long-term effectiveness. This trial is registered with ClinicalTrials.gov NCT03605563.

The importance of the local twitch response during needling interventions in spinal pain associated with myofascial trigger points: a systematic review and meta-analysis

OBJECTIVE

To compare the clinical effects of needling interventions eliciting local twitch responses (LTRs) versus needling without eliciting LTRs when applied to muscle trigger points (TrPs) associated with spinal pain of musculoskeletal origin.

DATABASES AND DATA TREATMENT

Electronic databases were searched for randomized or non-randomized clinical trials where one group received needling intervention where LTRs were elicited and was compared with another group receiving the same intervention without elicitation of LTRs in spinal pain disorders associated with TrPs. Outcomes included pain intensity, pain-related disability, and pressure pain thresholds. The risk of bias (RoB) was assessed using the Cochrane risk of bias tool or ROBINS-I tool, methodological quality was assessed with the PEDro score, and quality of evidence was evaluated using the GRADE approach.

RESULTS

Six trials were included. The application of a needling intervention eliciting LTRs was associated with a significant reduction in pain intensity immediately after treatment (mean difference (MD): -2.03 points, 95% confidence interval (CI): -3.77 to -0.29; standardized MD (SMD): -1.35, 95% CI: -2.32 to -0.38, p = 0.02) when compared to the same needling intervention without elicitation of LTRs. No effect at short-term follow-up (MD: -0.20 points, 95% CI: -1.46 to 1.06, p = 0.75) was observed. No significant differences based on elicitation or non-elicitation of LTRs were found in related disability (SMD: -0.05, 95% CI: -0.41 to 0.30, p = 0.77) or pressure pain thresholds (MD: 23.39 kPa, 95% CI: -13.68 to 60.47, p = 0.22).

DISCUSSION

Low-level evidence suggests an immediate effect of obtaining LTRs during needling interventions on pain intensity, with no significant effects on related disability or pressure pain sensitivity in spinal pain disorders associated with muscle TrPs.

REGISTRATION NUMBER

OSF Registry-https://doi.org/10.17605/OSF.IO/5ZX9N.

Pressure Pain Threshold in Patients With Chronic Pain: A Systematic Review and Meta-Analysis

INTRODUCTION

In chronic pain conditions, the pressure pain threshold has been used to investigate the presence of central sensitization.

METHODS

A systematic review and meta-analysis were conducted to compare the threshold in chronic pain patients and healthy individuals. Ovid MEDLINE and Embase up to July 2019 were used to conduct the search. Search strategy included terms and sets of terms that describe the concepts "sensory testing" and "pain measurement."

RESULTS

The included studies consisted of 24 were case-control studies and 12 cross-sectional studies. The pooled total sample size was 1280 cases of patients with different diagnoses of chronic pain and 1463 healthy controls. Among the included studies, 32 reported a significant decrease of the pressure pain threshold among patients compared with the controls and four reported no statistically significant difference. The pooled pressure pain threshold mean difference was -1.17 (95% confidence interval = -1.45 to -0.90). There was, however, evidence of significant heterogeneity across the studies (I2 = 87.42%, P < 0.001).

CONCLUSIONS

Patients who experience chronic pain have a significantly lower pressure pain threshold compared with healthy controls. Future research is needed to elucidate factors attributed to the change in pressure pain threshold among patients with chronic pain, as well as the time that the central sensitization occurs.

Current advances and novel research on minimal invasive techniques for musculoskeletal disorders

The present review summarized the current advances and novel research on minimal invasive techniques for musculoskeletal disorders. Different invasive approaches were proposed in the physical therapy field for the management of musculoskeletal disorders, such as ultrasound-guided percutaneous needle electrolysis, dry needling, acupuncture and other invasive therapy techniques, discussing about their worldwide status, safety and interventional ultrasound imaging. Indeed, dry needling may be one of the most useful and studies invasive physical therapy applications in musculoskeletal disorders of different body regions, such as back, upper limb, shoulder, arm, hand, pelvis, lower limb, neck, head, or temporomandibular joint, and multiple soreness location disorders, such as fibromyalgia. In addition, the assessment and treatment by acupuncture or electro-acupuncture was considered and detailed for different conditions such as plantar fasciitis, osteoarthritis, spasticity, myofascial pain syndrome, osteoporosis and rheumatoid arthritis. As an increasing technique in physical therapy, the use of ultrasound-guided percutaneous needle electrolysis was discussed in injuries of the musculoskeletal system and entrapment neuropathies. Also, ultrasound-guided percutaneous neuromodulation was established as a rising technique combined with ultrasound evaluation of the peripheral nerve system with different clinical applications which need further studies to detail their effectiveness in different musculoskeletal conditions. Thus, invasive physical therapy may be considered as a promising approach with different novel applications in several musculoskeletal disorders and a rising use in the physiotherapy field.

Sensory Processing in People With and Without Tendinopathy: A Systematic Review With Meta-analysis of Local, Regional, and Remote Sites in Upper- and Lower-Limb Conditions

OBJECTIVE

To synthesize results of somatosensory processing tests in people with upper- and lower-limb tendinopathy, compared to controls.

DESIGN

Systematic review with meta-analysis.

LITERATURE SEARCH

Four electronic databases (MEDLINE, CINAHL Plus, SPORTDiscus, and Embase) were searched.

STUDY SELECTION CRITERIA

Included studies measured a domain of sensory processing and compared a tendinopathy group to a healthy control group.

DATA SYNTHESIS

Meta-analysis was conducted for outcomes with homogeneous data from at least 2 studies. Upper- and lower-limb conditions were compared and outcomes were examined by measurement site (local, regional, or remote to location of pain).

RESULTS

Of the 30 studies included, 18 investigated lateral elbow tendinopathy. The most commonly assessed outcome measures were pressure pain threshold (PPT) and thermal pain threshold. There was moderate evidence for local and regional reduction of PPT in upper-limb tendinopathies, but not at remote sites. In lower-limb tendinopathies, there was conflicting evidence regarding reduced PPT at local sites and limited evidence of normal PPT at remote sites. There was moderate evidence of sensitization of thermal pain threshold at local sites in upper-limb tendinopathies and limited evidence of no difference in thermal pain threshold in lower-limb tendinopathies. Findings across other domains were variable.

CONCLUSION

Sensory processing was different between upper-limb tendinopathy and lower-limb tendinopathy. Upper-limb tendinopathies showed signs consistent with primary and secondary hyperalgesia, but lower-limb tendinopathies did not. There was mixed evidence for primary hyperalgesia and limited evidence against secondary hyperalgesia. J Orthop Sports Phys Ther 2021;51(1):12-26. doi:10.2519/jospt.2021.9417.

Healthy Pain-Free Individuals with a History of Distal Radius Fracture Demonstrate an Expanded Distribution of Experimental Referred Pain Toward the Wrist

OBJECTIVE

Nociception caused by injuries may sensitize central mechanisms causing expanded pain areas. After recovery, the status of such pain distribution and sensitivity mechanisms is unknown. The present study investigated whether individuals who have fully recovered from a distal radius fracture demonstrate increased pain sensitivity and expanded distribution of pressure-induced pain.

DESIGN

Cross-sectional single-blinded study.

SETTING

Clinical setting.

SUBJECTS

Twenty-three pain-free individuals with a history of painful distal radius fracture and 22 nonfractured, age/gender-matched controls participated in two experimental sessions (day 0, day 1) 24 hours apart.

METHODS

Pressure pain thresholds (PPTs) were recorded bilaterally at the extensor carpi radialis longus (ECRL), infraspinatus, and gastrocnemius muscles. Spatial distribution of pain was assessed following 60-second painful pressure stimulation at the ECRL (bilateral) and the infraspinatus muscles on the fractured or dominant side. Participants drew pain areas on a body map. After day 0 assessments, prolonged pain was induced by eccentric exercise of wrist extensors on the fractured/dominant side.

RESULTS

Compared with controls, pressure-induced ECRL pain in the fracture group referred more frequently toward the distal forearm (P < 0.005) on day 0. Both groups showed larger pain areas on day 1 compared with day 0 (P < 0.005), although the fracture group showed a larger relative change between days (P < 0.005). The fracture group showed larger pain areas on the fracture side compared with the contralateral side on both days (P < 0.005).

CONCLUSIONS

Prolonged pain and recovered prior painful injuries like fractures may sensitize pain mechanisms manifested as expanded pain distribution. Pressure-induced referred pain can be a simple pain biomarker for clinical use.

Effect of Physical Exercise Programs on Myofascial Trigger Points-Related Dysfunctions: A Systematic Review and Meta-analysis

OBJECTIVE

Myofascial pain syndrome is one of the primary causes of health care visits. In recent years, physical exercise programs have been developed for the treatment of myofascial trigger points, but their effect on different outcomes has not been clarified. Thus, this study aimed to assess the effect of physical exercise programs on myofascial trigger points.

METHODS

A systematic search was conducted in Pubmed, Web of Science, and Scopus. Articles analyzing the effect of physical exercise programs on pain intensity, pressure pain threshold, range of motion, and disability were included. Risk of bias was assessed using the Cochrane RoB2 tool. The DerSimonian-Laird method was used to compute the pooled effect sizes (ES) and their 95% confidence interval (95% CI) for pain intensity, pressure pain threshold, range of motion, and disability.

RESULTS

A total of 24 randomized controlled trials were included in this systematic review and meta-analysis. The pooled ES were -0.47 (95% CI = -0.61 to -0.33) for pain intensity, 0.63 (95% CI = 0.31 to 0.95) for pressure pain threshold, 0.43 (95% CI = 0.24 to 0.62) for range of motion, and -0.18 (95% CI = -0.45 to 0.10) for disability.

CONCLUSIONS

Physical exercise programs may be an effective approach in the treatment of pain intensity, pressure pain threshold, and range of motion among patients with myofascial trigger points.

Effects of trigger point dry needling on lateral epicondylalgia of musculoskeletal origin: a systematic review and meta-analysis

OBJECTIVE

This meta-analysis evaluated the effect of dry needling alone or combined with other treatment interventions on pain, related-disability, pressure pain sensitivity, and strength in people with lateral epicondylalgia of musculoskeletal origin.

DATA SOURCES

MEDLINE, CINAHL, PubMed, PEDro, Cochrane Library, SCOPUS and Web of Science databases from their inception to 5 April 2020.

REVIEW METHODS

Randomized controlled trials collecting outcomes on pain, related-disability, pressure pain thresholds, or strength where one group received dry needling for lateral epicondylalgia of musculoskeletal origin. The risk of bias was assessed by the Cochrane Guidelines, methodological quality was assessed with the PEDro score, and the quality of evidence by using the GRADE approach.

RESULTS

Seven studies including 320 patients with lateral epicondylalgia were included. The meta-analysis found that dry needling reduced pain intensity (SMD ‒1.13, 95%CI ‒1.64 to ‒0.62) and related-disability (SMD ‒2.17, 95%CI ‒3.34 to ‒1.01) with large effect sizes compared to a comparative group. Dry needling also increased pressure pain thresholds with a large effect size (SMD 0.98, 95%CI 0.30 to 1.67) and grip strength with a small size effect (SMD 0.48, 95%CI 0.16 to 0.81) when compared to a comparative group. The most significant effect was at short-term. The risk of bias was generally low, but the heterogenicity of the results downgraded the evidence level.

CONCLUSION

Low to moderate evidence suggests a positive effect of dry needling for pain, pain-related disability, pressure pain sensitivity and strength at short-term in patients with lateral epicondylalgia of musculoskeletal origin.

LEVEL OF EVIDENCE

Therapy, level 1a.

REGISTRATION NUMBER

OSF Registry - https://doi.org/10.17605/OSF.IO/ZY3E8.

Do joint mobilizations assist in the recovery of lateral elbow tendinopathy? A systematic review and meta-analysis

STUDY DESIGN

Systematic review.

INTRODUCTION

No consensus exists as to which are the most effective methods to treat the symptoms associated with lateral elbow tendinopathy (LET). Research has suggested that joint mobilizations may assist in the recovery of patients with LET.

PURPOSE OF THE STUDY

To determine if joint mobilizations are effective in improving pain, grip strength, and disability in adults with LET.

METHODS

Searches in 3 databases were performed to identify relevant clinical trials. Reviewers independently extracted data and assessed the methodological quality. Summary measures of quantitative data were extracted or calculated where possible. Appropriate data were pooled for meta-analysis using a random-effects model.

RESULTS

A total of 20 studies met the inclusion criteria; 7 were included in the meta-analysis. Studies were broadly classified into 3 groups: mobilization with movement (MWM), Mill's manipulation, and regional mobilization techniques. Pooled data across all time periods demonstrated a mean effect size of 0.43 (95% confidence interval [CI]: 0.15-0.71) for MWM on improving pain rating, and 0.31 (95% CI: 0.11-0.51) for MWM on improving grip strength, 0.47 (95% CI: 0.11-0.82) for Mill's manipulation on improving pain rating. A mean effect size of -0.01 (95% CI: -0.27 to -0.26) shows Mill's manipulation did not improve pain free grip strength. Functional outcomes varied considerably among studies. Pain, grip strength, and functional outcomes were improved with regional mobilizations.

CONCLUSION

There is compelling evidence that joint mobilizations have a positive effect on both pain and/or functional grip scores across all time frames compared to control groups in the management of LET.

Reorganized Force Control in Elbow Pain Patients During Isometric Wrist Extension

INTRODUCTION

Reorganized force control may be an important adaptation following painful traumas. In this study, force control adaptations were assessed in elbow pain patients. Increasing the contraction demand may overcome pain interference on the motor control and as such act as an internal control. It was hypothesized that elbow pain patients compared with controls would present greater change in the direction of force when increasing the demand of the motor task.

METHODS

Elbow pain patients (n=19) and asymptomatic participants (n=21) performed isometric wrist extensions at 5% to 70% of maximum voluntary contraction. Pressure pain thresholds were recorded at the lateral epicondyle and tibialis anterior muscle. Contraction force was recorded using a 3-directional force transducer. Participants performed contractions according to visual feedback of the task-related force intensity (main direction of wrist extension) and another set of contractions with feedback of the 3 force directions. Going from the simple to the detailed force feedback will increase the demand of the motor task. Force steadiness in all 3 dimensions and force directions were extracted.

RESULTS

Compared with controls, elbow pain patients presented lower pressure pain thresholds at both sites (P<0.05). Force steadiness was not significantly different between groups or feedback methods. The change in force direction when providing simple visual feedback in contrast with feedback of all force components at all contraction levels was greater for patients compared with controls (P<0.05).

CONCLUSION

The larger change in force direction in pain patients implies redistribution of loads across the arm as an associated effect of pain.

Trigger point dry needling for the treatment of myofascial pain syndrome: current perspectives within a pain neuroscience paradigm

Myofascial pain syndrome is a pain condition characterized by the presence of trigger points. Current evidence, mostly experimental studies, clearly supports a role of trigger points on peripheral and central sensitization since they are able to contribute to sensitization of peripheral nociceptors, spinal dorsal horn neurons, and the brainstem. Several interventions are proposed for treating trigger points, dry needling being one of the most commonly used by clinicians. There is no consensus on the clinical application of trigger point dry needling: some authors propose that local twitch responses should be elicited during the needling intervention to be effective, whereas others do not. The application of trigger point dry needling is able to reduce the excitability of the central nervous system by reducing peripheral nociception associated to the trigger point, by reducing dorsal horn neuron activity, and by modulating pain-related brainstem areas. However, the effects are mainly observed in the short-term, and effect sizes are moderateto small. Therefore, the current review proposes that the application of trigger point dry needling should be integrated into current pain neuroscience paradigm by combining its application with pain neuroscience education, graded exercise and manual therapy. Additionally, patient’s expectations, beliefs, previous experiences and patient–clinician interaction should be considered when integrating trigger point dry needling into a comprehensive treatment approach.

Ultrasound-Guided Percutaneous Electrical Nerve Stimulation of the Radial Nerve for a Patient With Lateral Elbow Pain: A Case Report With a 2-Year Follow-up

BACKGROUND

Patients with lateral elbow pain are often diagnosed with lateral epicondylalgia. Lateral elbow pain is often associated with dysfunction of the wrist extensor muscles; however, in some cases, it can also mimic signs and symptoms of radial nerve dysfunction.

CASE DESCRIPTION

In this case report, a 43-year-old man, who was originally referred with a diagnosis of lateral epicondylalgia as a result of playing table tennis and who previously responded favorably to manual therapy and exercise, presented to the clinic for treatment. An exacerbation while participating in a table tennis match resulted in a return of his lateral epicondylalgia symptoms, which did not respond favorably to the same interventions used in his prior course of therapy. Further examination revealed sensitization of the radial nerve, which was treated with 2 sessions of ultrasound-guided percutaneous electrical nerve stimulation and 4 weeks of a low-load, concentric/eccentric exercise program for the wrist extensors.

OUTCOMES

Following this intervention, the patient experienced clinically meaningful improvement in pain intensity (numeric pain-rating scale), function (Patient-Rated Tennis Elbow Evaluation), and related disability (Disabilities of the Arm, Shoulder and Hand questionnaire). The patient progressively exhibited complete resolution of pain and function, which was maintained at 2 years.

DISCUSSION

This case report demonstrates the outcomes of a patient with lateral elbow pain who did not respond to manual therapy and exercise. Once radial nerve trunk sensitivity was identified and the intervention, consisting of ultrasound-guided percutaneous electrical nerve stimulation targeting the radial nerve combined with a low-load exercise program, was applied, a full resolution of pain and function occurred rapidly. Future clinical trials should examine the effect of percutaneous electrical nerve stimulation in the management of nerve-related symptoms associated with musculoskeletal pain conditions.

LEVEL OF EVIDENCE

Therapy, level 5. J Orthop Sports Phys Ther 2019;49(5):347-354. Epub 18 Jan 2019. doi:10.2519/jospt.2019.8570.

Lateral epicondylalgia: A primary nervous system disorder

Lateral epicondylalgia (LE) is the most common chronic painful condition affecting the elbow in the general population. Although major advances have been accomplished in recent years in the understanding of LE, the underlying physiopathology is still a reason for debate. Differences in clinical presentation and evolution of the symptoms among patients, suggest the need for revisiting the current knowledge about subjacent mechanisms that attempt to explain pain and functional loss. Previous models have suggested that the condition is mainly a degenerative tendinopathy, associated with changes in pain pathways and the motor system. The hypothesis of this work is that LE is the clinical manifestation of a primary nervous system disorder, characterized by an abnormal increase in neuronal activity and a subsequent loss of homeostasis, which secondarily affects the musculoskeletal tissues of the elbow-forearm-hand complex. A new model for LE is presented, supported by an in-deep analysis of basic sciences, epidemiological and clinical studies.

Post-needling soreness after myofascial trigger point dry needling: Current status and future research

Post-dry needling soreness is a common complication of myofascial trigger point (MTrP) dry needling treatment. The prevention, management and relevance of this complication remain uncertain. This paper examines the current state of knowledge and suggests directions for further studies in this area. MTrPs are hypersensitive nodules in skeletal muscles' taut bands, present in several pain conditions. Dry needling has been recommended for relieving MTrP pain. MTrP dry needling procedures have shown to be associated with post-needling soreness, which is thought to be a consequence of the neuromuscular damage, and hemorrhagic and inflammatory reaction generated by the needle. Postneedling soreness is a very frequent effect after deep dry needling, usually lasting less than 72 h. It may not be especially distressing for most patients. However, patients presenting with higher levels of post-needling soreness, not perceiving dry needling effectiveness in the first session, or not having high myofascial pain intensity before treatment, could be the most likely to find post-needling soreness more distressing, functionally limiting and to abandon treatment. Future research should assess the clinical relevance of post-needling soreness. Post-needling soreness should be considered when investigating dry needling effectiveness since it could overlie the original myofascial pain and influence the patients' pain ratings.

Effect of wrist and finger flexion in relation to strain on the tendon origin of the extensor carpi radialis brevis: A cadaveric study simulating stretching exercises

BACKGROUND

Stretching exercises based on wrist flexion-ulnar deviation with elbow extension, forearm pronation, and additional index or middle finger flexion have been used to stretch the wrist extensors for lateral epicondylitis. The purpose of this study was to quantify the strain on the tendon origin of the extensor carpi radialis brevis in cadaver specimens during these stretching exercises.

METHODS

We used 8 fresh frozen/thawed cadaveric upper extremities. The strain on the extensor carpi radialis brevis tendon origin was measured by the addition of 4 types of traction (no traction, wrist flexion-ulnar deviation, and index or middle finger flexion in combination with wrist flexion-ulnar deviation) in 7 sequential elbow flexion angles during forearm pronation. Two types of varus stress load to the elbow (none, gravity on the forearm) were also applied.

FINDINGS

A significant increase in strain was obtained by wrist traction with 0°, 15° and 30° of elbow flexion (P<0.05). The strain was also significantly increased by adding finger traction (P<0.05) and varus stress load (P<0.05). A maximum strain value of 5.30 (SD 1.73) % was obtained when traction on the middle finger in combination with traction of the wrist was added at 15° elbow flexion with varus stress load.

INTERPRETATION

The present study provides data about the amount of strain on the extensor carpi radialis brevis tendon during stretching exercises of the wrist and finger extensors. The results of this study could be applied to stretching exercises for patients with lateral epicondylitis.

Association between Epicondylitis and Cardiovascular Risk Factors in Pooled Occupational Cohorts

Background

The pathophysiology of lateral epicondylitis (LE) is unclear. Recent evidence suggests some common musculoskeletal disorders may have a basis in cardiovascular disease (CVD) risk factors. Thus, we examined CVD risks as potential LE risks.

Methods

Workers (n = 1824) were enrolled in two large prospective studies and underwent structured interviews and physical examinations at baseline. Analysis of pooled baseline data assessed the relationships separately between a modified Framingham Heart Study CVD risk score and three prevalence outcomes of: 1) lateral elbow pain, 2) positive resisted wrist or middle finger extension, and 3) a combination of both symptoms and at least one resisted maneuver. Quantified job exposures, personal and psychosocial confounders were statistically controlled. Odds ratios (ORs) and 95% Confidence Intervals (CIs) were calculated.

Results

There was a strong relationship between CVD risk score and lateral elbow symptoms, resisted wrist or middle finger extension and LE after adjustment for confounders. The adjusted ORs for symptoms were as high as 3.81 (95% CI 2.11, 6.85), for positive examination with adjusted odds ratios as high as 2.85 (95% CI 1.59, 5.12) and for combined symptoms and physical examination 6.20 (95% CI 2.04, 18.82). Relationships trended higher with higher CVD risk scores.

Conclusions

These data suggest a potentially modifiable disease mechanism for LE.

Effects of Low-Load Exercise on Postneedling-Induced Pain After Dry Needling of Active Trigger Point in Individuals With Subacromial Pain Syndrome

BACKGROUND

The application of dry needling usually is associated with postneedling-induced pain. A postneedling intervention to reduce this adverse event is needed.

OBJECTIVE

To determine the effectiveness of low-load exercise on reducing postneedling-induced pain after dry needling of active trigger points (TrPs) in the infraspinatus muscle in subacromial pain syndrome.

DESIGN

A 72-hour follow-up, single-blind randomized controlled trial.

SETTING

Urban hospitals.

PARTICIPANTS

Individuals with subacromial pain syndrome (n = 90, 52% female, mean age: 35 ± 13 years) with active TrPs in the infraspinatus muscle.

INTERVENTIONS

All individuals received dry needling into the infraspinatus active TrP. Then, they were divided randomly into an experimental group, which received a single bout of low-load exercise of shoulder muscles; a placebo group, which received inactive ultrasound for 10 minutes; and a control group, which did not receive any intervention.

OUTCOME MEASURES

Numerical Pain Rating Scale (0-10 point) was administered postneedling, immediately postintervention (2 minutes), and 24, 48, and 72 hours after needling. Shoulder pain (Numerical Pain Rating Scale, 0-10) and disability (Disabilities of the Arm, Shoulder and Hand; Shoulder Pain and Disability Index) were assessed before and 72 hour after needling.

RESULTS

The 5 × 3 analysis of covariance showed that the exercise group demonstrated a larger decrease in postneedling-induced pain immediately after (P = .001), 24 hours (P = .001), and 48 hours after (P = .006) than placebo or control groups. No differences were found at 72 hours (P = .03). Similar improvements in shoulder pain (P < .001) and related disability (Disabilities of the Arm, Shoulder and Hand: P < .001; Shoulder Pain and Disability Index: P < .001) were observed 72 hours after needling, irrespective of the treatment group.

CONCLUSIONS

Low-load exercise was effective for reducing postneedling-induced pain on active TrPs in the infraspinatus muscle 24 and 48 hours after needling. The application of a postneedling intervention did not influence short-term pain and disability changes.

LEVEL OF EVIDENCE

I.

The local twitch response during trigger point dry needling: Is it necessary for successful outcomes?

BACKGROUND

Myofascial trigger point (MTrP) injection and trigger point dry needling (TrPDN) are widely accepted therapies for myofascial pain syndrome (MPS). Empirical evidence suggests eliciting a local twitch response (LTR) during needling is essential.

OBJECTIVE

This is the first review exploring the available literature, regardless of study design, on the neurophysiological effects and clinical significance of the LTR as it relates to reductions in pain and disability secondary to MTrP needling.

METHODS

PubMed, MEDLINE, Science Direct and Google Scholar were searched up until October 2016 using terms related to trigger point needling and the LTR.

RESULTS

and Discussion: Several studies show that eliciting a LTR does not correlate with changes in pain and disability, and multiple systematic reviews have failed to conclude whether the LTR is relevant to the outcome of TrPDN. Post needling soreness is consistently reported in studies using repeated in and out needling to elicit LTRs and increases in proportion to the number of needle insertions. In contrast, needle winding without LTRs to MTrPs and connective tissue is well supported in the literature, as it is linked to anti-nociception and factors related to tissue repair and remodeling. Additionally, the positive biochemical changes in the MTrP after needling may simply be a wash out effect related to local vasodilation. While the LTR during TrPDN appears unnecessary for managing myofascial pain and unrelated to many of the positive effects of TrPDN, further investigation is required.

Comparison of hand grip strength and upper limb pressure pain threshold between older adults with or without non-specific shoulder pain

Background

There is a high prevalence of non-specific shoulder pain associated with upper limb functional limitations in older adults. The purpose of this study was to determine the minimal clinically important differences (MCID) of grip strength and pressure pain threshold (PPT) in the upper limb between older adults with or without non-specific shoulder pain.

Methods

A case-control study was carried out following the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria. A sample of 132 shoulders (mean ± SD years) with (n = 66; 76.04 ± 7.58) and without (n = 66; 75.05 ± 6.26) non-specific pain were recruited. The grip strength and PPT of the anterior deltoid and extensor carpi radialis brevis (ECRB) muscles were assessed.

Results

There were statistically significant differences (mean ± SD; P-value) for anterior deltoid PPT (2.51 ± 0.69 vs 3.68 ± 0.65, kg/cm²; P < .001), ECRB PPT (2.20 ± 0.60 vs 3.35 ± 0.38 kg/cm²; P < .001) and grip strength (20.78 ± 10.94 vs 24.63 ± 9.38 kg; P = .032) between shoulders with and without non-specific pain, respectively.

Discussion

The MCID of 1.17 kg/cm², 1.15 kg/cm² and 3.84 kg were proposed for anterior deltoid PPT, ECRB PPT and grip strength, respectively, to assess the upper limb of older adults with non-specific shoulder pain after treatment. In addition, univariate and multivariate (linear regression and regression trees) analyses may be used to consider age distribution, sex, pain intensity, grip strength and PPT in older adults including clinical and epidemiological studies with non-specific shoulder pain.

Contribution of Dry Needling to Individualized Physical Therapy Treatment of Shoulder Pain: A Randomized Clinical Trial

Study Design Multicenter, parallel randomized clinical trial. Background Myofascial trigger points (MTrPs) are implicated in shoulder pain and functional limitations. An intervention intended to treat MTrPs is dry needling. Objectives To investigate the effectiveness of dry needling in addition to evidence-based personalized physical therapy treatment in the treatment of shoulder pain. Methods One hundred twenty patients with nonspecific shoulder pain were randomly allocated into 2 parallel groups: (1) personalized, evidencebased physical therapy treatment; and (2) trigger point dry needling in addition to personalized, evidence-based physical therapy treatment. Patients were assessed at baseline, posttreatment, and 3-month follow-up. The primary outcome measure was pain assessed by a visual analog scale at 3 months, and secondary variables were joint range-of-motion limitations, Constant-Murley score for pain and function, and number of active MTrPs. Clinical efficacy was assessed using intention-to-treat analysis. Results Of the 120 enrolled patients, 63 were randomly assigned to the control group and 57 to the intervention group. There were no significant differences in outcome between the 2 treatment groups. Both groups showed improvement over time. Conclusion Dry needling did not offer benefits in addition to personalized, evidencebased physical therapy treatment for patients with nonspecific shoulder pain. Level of Evidence Therapy, level 1b. Registered February 11, 2009 at www.isrctn.com (ISRCTN30907460). J Orthop Sports Phys Ther 2017;47(1):11-20. Epub 9 Dec 2016. doi:10.2519/jospt.2017.6698.

Multimodal approach to rehabilitation of the patients with lateral epicondylosis: a case series

Purpose

The objective of this study was to evaluate the effectiveness of mobilization with movement and kinesiotherapy in the treatment of patients with lateral epicondylosis.

Methods

This cases series included eight volunteers who had chronic lateral epicondylosis. The patients were treated with stretching, massage deep transverse at the lateral epicondyle and mobilization with movement associated with eccentric exercise. The mobilization with movement that consisted of a force of lateral glide of the proximal forearm. We performed twelve sessions, twice a week for 45 min/session. All patients underwent an evaluation with a visual analog scale and functional assessment through questionnaires patient-rated tennis elbow evaluation (PRTEE) and disabilities of the arm, shoulder and hand (DASH), before and after the treatment. Data were analyzed by student’s t test (p < 0.05).

Results

The results showed statistical differences in pain symptoms before and after treatment, in the analysis and functional assessment through both questionnaires comparing the pre and post treatment.

Conclusion

The data obtained in this study demonstrates improvement of the function and pain status of the sample investigated.

A critical overview of the current myofascial pain literature - September 2016

This edition of the overview of the current myofascial pain literature includes 24 studies, case reports and systematic and narrative reviews. Surprisingly, five of the 24 papers were difficult to read and interpret mostly because of a poor mastery of the English language. It is somewhat surprising that journal editors and reviewers would accept papers that are needlessly difficult to read and not direct the authors to language services or others who could improve the quality of the writings. Of course, it is exciting that researchers and clinicians from all over the world continue to focus on myofascial pain and attempt to shed new light on the complexity of the problem to improve the clinical decision-making process and eventually clinical approaches and outcomes. There were no new papers on manual therapies, but many focused on dry needling.

Experienced versus Inexperienced Interexaminer Reliability on Location and Classification of Myofascial Trigger Point Palpation to Diagnose Lateral Epicondylalgia: An Observational Cross-Sectional Study

The purpose was to evaluate the interexaminer reliability of experienced and inexperienced examiners on location and classification of myofascial trigger points (MTrPs) in two epicondylar muscles and the association between the MTrP found and the diagnosis of lateral epicondylalgia (LE). Fifty-two pianists (some suffered LE) voluntarily participated in the study. Three physiotherapists (one inexperienced in myofascial pain) examined, located, and marked MTrPs in the extensor carpi radialis brevis (ECRB) and extensor digitorum communis (EDC) muscles. Forearms were photographed and analyzed to establish the degree of agreement on MTrPs diagnosis. Data showed 81.73% and 77.88% of agreement on MTrP classification and 85.58% and 72.12% on MTrP location between the expert evaluators for ECRB and EDC, respectively. The agreement on MTrP classification between experienced and inexperienced examiners was 54.81% and 51.92% for ECRB and 50.00% and 55.77% for EDC. Also, agreement on MTrP location was 54.81% and 60.58% for ECRB and 48.08% and 48.08% for EDC. A strong association was found between presence of relevant MTrPs, LE diagnosis, and forearm pain when the examiners were experts. The analysis of location and classification of MTrPs in the epicondylar muscles through physical examination by experienced evaluators is reliable, reproducible, and suitable for diagnosing LE.

Evidence of Nervous System Sensitization in Commonly Presenting and Persistent Painful Tendinopathies: A Systematic Review

Study Design Systematic review. Objectives To elucidate if there is sensitization of the nervous system in those with persistent rotator cuff (shoulder), lateral elbow, patellar, and Achilles tendinopathies. Background Tendinopathy can be difficult to treat, and persistent intractable pain and dysfunction are frequent. It is hypothesized that induction or maintenance of persistent pain in tendinopathy may be, at least in part, based on changes in the nervous system. Methods The PRISMA guidelines were followed. Relevant articles were identified through a computerized search in Embase, PubMed, and Web of Science, followed by a manual search of reference lists of retained articles. To be eligible, studies had to include quantitative sensory testing and evaluate individuals diagnosed with a persistent tendinopathy of the rotator cuff (shoulder), lateral elbow, patella, or Achilles tendon. Methodological quality assessment was evaluated with the Newcastle-Ottawa Scale. Results In total, 16 full-text articles met the criteria for inclusion, of which the majority were case-control studies with heterogeneous methodological quality. No studies on Achilles tendinopathy were found. Mechanical algometry was the predominant quantitative sensory testing used. Lowered pressure pain threshold was observed across different tendinopathies at the site of tendinopathy, as well as at other sites, the latter being suggestive of central sensitization. Conclusion Although more research on sensory abnormalities is warranted, it appears likely that there is an association between persistent tendon pain and sensitization of the nervous system. This evidence is primarily from studies of upper-limb tendinopathy, and caution should be exercised with inference to lower-limb tendinopathy. J Orthop Sports Phys Ther 2015;45(11):864-875. Epub 21 Sep 2015. doi:10.2519/jospt.2015.5895.

Association between muscle trigger points, ongoing pain, function, and sleep quality in elderly women with bilateral painful knee osteoarthritis

OBJECTIVE

The objectives of this study were to investigate if referred pain elicited by active trigger points (TrPs) reproduced the symptoms in individuals with painful knee osteoarthritis (OA) and to determine the relationship between the presence of active TrPs, intensity of ongoing pain, function, quality of life, and sleep quality in individuals with painful knee OA.

METHODS

Eighteen women with bilateral painful knee OA, aged 79 to 90 years, and 18 matched controls participated. Muscle TrPs were bilaterally explored in several muscles of the lower extremity. Trigger points were considered active if the elicited referred pain reproduced knee symptoms, and TrPs were considered latent if the elicited pain did not reproduce symptoms. Pain was collected with a numerical pain rate scale (0-10), function was assessed with Western Ontario and McMaster Universities, quality of life was assessed with the Medical Outcomes Study Short Form 36 questionnaire, and sleep quality was determined with the Pittsburgh Sleep Quality Index.

RESULTS

Women with knee OA exhibited a greater number of active TrPs (mean, 1 ± 1; P < .001) but similar number of latent TrPs (mean, 4 ± 2) than healthy women (mean, 4 ± 3; P = .613). A greater number of active TrPs were associated with higher intensity of ongoing pain (r = 0.605; P = .007). Higher intensity of ongoing knee pain was associated with lower physical function (P < .05).

CONCLUSIONS

The referred pain elicited by active TrPs in the lower extremity muscles contributed to pain symptoms in painful knee OA. A higher number of active TrPs was associated with higher intensity of ongoing knee pain.

Myofascial trigger points: peripheral or central phenomenon?

Trigger points (TrP) are hyperirritable spots in a taut band of a skeletal muscle, which usually have referred pain. There is controversy over whether TrP are a peripheral or central nervous system phenomenon. Referred pain, the most characteristic sign of TrP, is a central phenomenon initiated and activated by peripheral sensitization, whereby the peripheral nociceptive input from the muscle can sensitize dorsal horn neurons that were previously silent. TrP are a peripheral source of nociception, and act as ongoing nociceptive stimuli contributing to pain propagation and widespread pain. Several studies support the hypothesis that TrP can induce central sensitization, and appropriate TrP treatment reduces central sensitization. In contrast, preliminary evidence suggests that central sensitization can also promote TrP activity, although further studies are needed. Proper TrP management may prevent and reverse the development of pain propagation in chronic pain conditions, because inactivation of TrP attenuates central sensitization.

Effects of spray and stretch on postneedling soreness and sensitivity after dry needling of a latent myofascial trigger point

OBJECTIVES

To investigate (1) the effect of spray and stretch versus control on reducing postneedling soreness of 1 latent myofascial trigger point (MTrP) and (2) whether higher levels of psychological distress are associated with increased postneedling pain intensity.

DESIGN

A 72-hour follow-up, single-blind randomized controlled trial.

SETTING

University community.

PARTICIPANTS

Healthy volunteers (N=70; 40 men, 30 women) aged 18 to 36 years (mean age, 21±4y) with latent MTrP in 1 upper trapezius muscle.

INTERVENTION

All subjects received a dry needling application over the upper trapezius muscle. Then, participants were randomly divided into 2 groups: an intervention group, which received spray and stretch over the needled trapezius muscle, and a control group, which did not receive any intervention.

MAIN OUTCOME MEASURES

Visual analog scale (at postneedling, posttreatment, and 6, 12, 24, 48, and 72h after needling), pressure pain threshold (at preneedling, postneedling, and 24 and 48h after needling). Psychological distress was evaluated by using the Symptom Checklist-90-Revised.

RESULTS

Repeated-measures analysis of variance demonstrated a significant interaction between group and time (F3,204.8=3.19; P<.05; ηp(2)=.04) for changes in postneedling soreness. Between-group differences were significant only immediately after intervention (P=.002), and there were no differences found between groups after 6 hours of the intervention (P>.05). Repeated measures of covariance showed that none of the psychological covariates affected these results. Somatization, anxiety, interpersonal sensitivity, and hostility were significantly correlated (P<.05) with postneedling pain intensity. Repeated-measures analysis of variance did not show a significant effect of spray and stretch on mechanical hyperalgesia (F2.6,175=1.9; P=.131; ηp(2)=.02).

CONCLUSIONS

The spray and stretch had a short-term (<6h) effect in reducing postneedling soreness of a latent MTrP. Pressure pain threshold did not significantly change after spray and stretch. Psychological factors are related to postneedling pain.

Myofascial pain syndrome treatments

Myofascial pain syndrome (MPS) is a regional pain disorder caused by taut bands of muscle fibers in skeletal muscles called myofascial trigger points. MPS is a common disorder, often diagnosed and treated by physiatrists. Treatment strategies for MPS include exercises, patient education, and trigger point injection. Pharmacologic interventions are also common, and a variety of analgesics, antiinflammatories, antidepressants, and other medications are used in clinical practice. This review explores the various treatment options for MPS, including those therapies that target myofascial trigger points and common secondary symptoms.

Bilateral myofascial trigger points and pressure pain thresholds in the shoulder muscles in patients with unilateral shoulder impingement syndrome: a blinded, controlled study

OBJECTIVES

To identify the presence of myofascial trigger points (TrPs) and pressure pain threshold (PPT) levels in the shoulder muscles of both involved and uninvolved sides in patients with unilateral shoulder impingement syndrome (SIS).

METHODS

Twenty-seven patients with SIS and 20 matched control patients participated in this study. TrPs of 10 shoulder muscles and 8 PPTs, including tibialis anterior PPT, were assessed.

RESULTS

SIS group showed a greater number of TrPs (t=-2.697; P=0.010) than the control group. The muscles of the uninvolved side of the SIS group also presented some active TrPs. PPTs showed small differences between involved and uninvolved sides of patients with SIS and higher differences between both sides of the SIS group and dominant side of controls although with significant difference only in the supraspinatus PPT (F=3.239; P=0.045). The muscle PPTs of the patients presenting TrPs in each muscle of the involved side were lower than the PPTs of the patients without TrPs in the same muscle for both involved and uninvolved sides with few significant differences.

DISCUSSION

The high number of TrPs in the involved side of patients with SIS suggests the presence of peripheral sensitization. The results reject the presence of central alterations. Finally, the patients with unilateral SIS may present bilateral deficits related to myofascial pain.

Myofascial trigger points, pain, disability, and sleep quality in individuals with mechanical neck pain

OBJECTIVE

The purpose of this study was to investigate the presence of active myofascial trigger points (MTrPs) in a greater number of muscles than previous studies and the relation between the presence of MTrPs, the intensity of pain, disability, and sleep quality in mechanical neck pain.

METHODS

Fifteen patients with mechanical neck pain (80% women) and 12 comparable controls participated. Myofascial trigger points were bilaterally explored in the upper trapezius, splenius capitis, semispinalis capitis, sternocleidomastoid, levator scapulae, and scalene muscles in a blinded design. Myofascial trigger points were considered active if the subject recognized the elicited referred pain as a familiar symptom. Myofascial trigger points were considered latent if the elicited referred pain was not recognized as a symptom. Pain was collected with a numerical pain rate scale (0-10); disability was assessed with Neck Disability Index; and sleep quality, with the Pittsburgh Sleep Quality Index.

RESULTS

Patients exhibited a greater disability and worse sleep quality than controls (P < .001). The Pittsburgh Sleep Quality Index score was associated with the worst intensity of pain (r = 0.589; P = .021) and disability (r = 0.552; P = .033). Patients showed a greater (P = .002) number of active MTrPs (mean, 2 ± 2) and similar number (P = .505) of latent MTrPs (1.6 ± 1.4) than controls (latent MTrPs, 1.3 ± 1.4). No significant association between the number of latent or active MTrPs and pain, disability, or sleep quality was found.

CONCLUSIONS

The referred pain elicited by active MTrPs in the neck and shoulder muscles contributed to symptoms in mechanical neck pain. Patients exhibited higher disability and worse sleep quality than controls. Sleep quality was associated with pain intensity and disability. No association between active MTrPs and the intensity of pain, disability, or sleep quality was found.