A systematic comparison between subjects with no pain and pain associated with active myofascial trigger points

MR elastography-based slip interface imaging (SII) for functional assessment of myofascial interfaces: A feasibility study

PURPOSE

Abnormal adherence at functional myofascial interfaces is hypothesized as an important phenomenon in myofascial pain syndrome. This study aimed to investigate the feasibility of MR elastography (MRE)-based slip interface imaging (SII) to visualize and assess myofascial mobility in healthy volunteers.

METHODS

SII was used to assess local shear strain at functional myofascial interfaces in the flexor digitorum profundus (FDP) and thighs. In the FDP, MRE was performed at 90 Hz vibration to each index, middle, ring, and little finger. Two thigh MRE scans were performed at 40 Hz with knees flexed and extended. The normalized octahedral shear strain (NOSS) maps were calculated to visualize myofascial slip interfaces. The entropy of the probability distribution of the gradient NOSS was computed for the two knee positions at the intermuscular interface between vastus lateralis and vastus intermedius, around rectus femoris, and between vastus intermedius and vastus medialis.

RESULTS

NOSS map depicted distinct functional slip interfaces in the FDP for each finger. Compared to knee flexion, clearer slip interfaces and larger gradient NOSS entropy at the vastus lateralis-vastus intermedius interface were observed during knee extension, where the quadriceps are not passively stretched. This suggests the optimal position for using SII to visualize myofascial slip interface in skeletal muscles is when muscles are not subjected to any additional force.

CONCLUSION

The study demonstrated that MRE-based SII can visualize and assess myofascial interface mobility in extremities. The results provide a foundation for investigating the hypothesis that myofascial pain syndrome is characterized by changes in the mobility of myofascial interfaces.

Sleep, Caffeine, BMI, and Pressure Pain Threshold in Temporomandibular Disorder Patients: An Observational Study

BACKGROUND

Temporomandibular disorders (TMDs) represent a multifactorial condition involving a multitude of symptoms of the temporomandibular joint that emanates a series of distress. Understanding the relationship between these lifestyle factors and pain perception in TMD patients is essential for optimizing their management and care. This study delves into the intricate interplay between sleep, caffeine consumption, body mass index (BMI), and the potential effect on pressure pain threshold (PPT) values among individuals with TMDs.

MATERIALS AND METHODS

This is an observational study. Data were collected from a convenient sample of female patients at a single center in Riyadh city, between the ages of 20 and 50 years. The variables collected were based on an operator-designed questionnaire, the symptom questionnaire, and the Diagnostic Criteria for Temporomandibular Joint Disorders (DC/TMD).

RESULTS

A total of 139 participants were included in the study, appraising the occurrence of TMD and pain as per reports of caffeine intake and sleep duration. The observed outcomes indicate that the amount of sleep has a significant effect on the PPT values in TMD patients. This study highlights the substantial impact of sleep duration on lowering PPT values in individuals with TMDs. The findings highlight the importance of considering sleep duration and caffeine intake in the comprehensive management of TMD patients. There was no effect of BMI on this particular sample.

CONCLUSION

This study shows a positive correlation between sleep and pain and TMD, caffeine, and pain. A deeper understanding of these relationships could pave the way for more effective pain management strategies and personalized treatment approaches tailored to the unique needs of TMD patients. BMI had no effect.

Botulinum toxin-A effects on pain, somatosensory and psychosocial features of patients with refractory masticatory myofascial pain: a randomized double-blind clinical trial

The antinociceptive effect of BoNT-A have been well documented in animal studies; however, results of few but well-designed randomized placebo-controlled clinical trials about BoNT-A efficacy in masticatory myofascial pain (MFP) are inconsistent. Therefore, the present randomized, double-blind, placebo-controlled clinical trial evaluated the efficacy of BoNT-A in patients with refractory MFP. Twenty-eight patients with pain reduction of less than 30% despite conservative treatment and with an average pain intensity of > 50 mm on the visual analogue scale (VAS) participated. Patients were randomly assigned to receive a total of 80 U of BoNT-A or saline solution (SS) injected into the masseter and anterior temporalis muscles. Pain intensity (VAS), quantitative sensory testing (QST), conditioned pain modulation (CPM), and psychosocial status were examined. Follow-up was performed at 1 and 6 months. For repeated-measure comparisons between evaluation times, Friedman test with Bonferroni correction was used for pain and somatosensory variables and the Wilcoxon test for the psychosocial variables. The Mann-Whitney test was used for all comparisons between groups. The BoNT-A group had a significant decrease in pain intensity at follow-ups compared with the SS group (p < 0.001). QST assessment revealed higher pressure pain threshold values in the masseter muscle for BoNT-A group compared to SS (p < 0.03) at all follow-ups. No differences were found for mechanical pain threshold and wind-up ratio values (p > 0.05) in the entire study. The BoNT-A group presented the most efficient CPM effect (p < 0.03) only at the 1 month follow-up in the masseter muscle. There was a significant time effect for BoNT-A in all psychosocial variables (p < 0.05) and a drug effect in the Central Sensitization Inventory (p < 0.01), Pittsburgh Sleep Quality Index (p < 0.004), and Healthy Survey 36 (p < 0.05) at 6 months follow-up. The study demonstrates that a single injection-session of BoNT-A has positive effects on the hall pain spectrum of patients with refractory masticatory myofascial pain.

Effects of Myofascial Induction Therapy on Ankle Range of Motion and Pressure Pain Threshold in Trigger Points of the Gastrocnemius-A Clinical Trial

BACKGROUND

The myofascial induction technique (MIT) has been shown to increase shoulder range of motion (ROM) in breast cancer survivors and decrease pain pressure threshold over the radial nerve in patients with epicondylalgia. To the authors' best knowledge, no study on trigger points and MIT has been published to date. The effect on ROM of latent trigger points is also unknown.

METHODS

A total of 20 twins with one latent trigger point of the gastrocnemius muscle were evaluated pre- and post-MIT in the calf. We measured static footprint variables in a pre-post study.

RESULTS

We found differences in PPT (p = 0.001) and no differences in ROM with knee flexed (p = 0.420) or stretched (p = 0.069).

CONCLUSIONS

After Calf MIT, latent myofascial trigger points improve PPT but no change in ankle dorsiflexion with knee bent or knee flexed were found in non-restriction healthy subjects.

Evidence for an association of serum microanalytes and myofascial pain syndrome

BACKGROUND

Myofascial Pain Syndrome (MPS) is a common pain disorder. Diagnostic criteria include physical findings which are often unreliable or not universally accepted. A precise biosignature may improve diagnosis and treatment effectiveness. The purpose of this study was to assess whether microanalytic assays significantly correlate with characteristic clinical findings in people with MPS.

METHODS

This descriptive, prospective study included 38 participants (25 women) with greater than 3 months of myofascial pain in the upper trapezius. Assessments were performed at a university laboratory. The main outcome measures were the Beighton Index, shoulder range of motion, strength asymmetries and microanalytes: DHEA, Kynurenine, VEGF, interleukins (IL-1b, IL-2, IL-4, IL-5, IL-7, IL-8, IL-13), growth factors (IGF-1, IGF2, G-CSF, GM-CSF), MCP-1, MIP-1b, BDNF, Dopamine, Noradrenaline, NPY, and Acetylcholine. Mann-Whitney test and Spearman's multivariate correlation were applied for all variables. The Spearman's analysis results were used to generate a standard correlation matrix and heat map matrix.

RESULTS

Mean age of participants was 32 years (20-61). Eight (21%) had widespread pain (Widespread Pain Index ≥ 7). Thirteen (34%) had MPS for 1-3 years, 14 (37%) 3-10 years, and 11 (29%) for > 10 years. The following showed strong correlations: IL1b,2,4,5,7,8; GM-CSF and IL 2,4,5,7; between DHEA and BDNF and between BDNF and Kynurenine, NPY and acetylcholine. The heat map analysis demonstrated strong correlations between the Beighton Index and IL 5,7, GM-CSF, DHEA. Asymmetries of shoulder and cervical spine motion and strength associated with select microanalytes.

CONCLUSION

Cytokine levels significantly correlate with selected clinical assessments. This indirectly suggests possible biological relevance for understanding MPS. Correlations among some cytokine clusters; and DHEA, BDNF kynurenine, NPY, and acetylcholine may act together in MPS. These findings should be further investigated for confirmation that link these microanalytes with select clinical findings in people with MPS.

The Effect of ISBT-Bowen Therapy in the Treatment of Myofascial Neck Pain-a Randomized, Single-Blinded Clinical Trial

Background

Myofascial pain syndrome (MPS) is the most common diagnosis in patient presenting with chronic non-specific neck pain. It affects people's work performance, productivity, and quality of life. To date, there is little research evaluating the effectiveness of non-invasive techniques, such as ISBT-Bowen Therapy in managing neck MPS.

Objectives

To investigate the effectiveness of Bowen therapy in managing myofascial pain syndrome with symptoms lasting for more than six weeks. The study will also examine the long-term effect of ISBT-Bowen Therapy on functional enhancement, quality of life, and physical and mental well-being.

Methods

This is a prospective, single-blinded randomized controlled trial (RCT). A total of 90 myofascial neck pain patients were recruited and randomized to receive 8 sessions of ISBT-Bowen Therapy over a 12-week period (n = 45) or to continue their usual conventional treatment (n = 45). Pressure pain threshold (PPT), cervical range of motion (CROM), numerical rating pain scores, Neck Disability Index (NDI), SF-12 Health Survey (SF-12) Version 2, Generalized Anxiety Disorder 7-item (GAD7), and Patient Health Questionnaire (PHQ9) were measured at baseline, 12 weeks, and 24 weeks after baseline.

Results

When compared with the control group, PPT significantly increased after ISBT-Bowen Therapy at 12 and 24 weeks. CROM on flexion, lateral flexion, and rotation were greatly improved at 12 weeks after Bowen therapy, and maintained at 24 weeks, except left lateral flexion. NDI, GAD7, and PHQ9 were all reduced after Bowen Therapy at both 12 and 24 weeks. Both Physical and Mental Component Summary scores of SF-12 were improved after Bowen therapy at 12 and 24 weeks.

Conclusions

This study confirmed the efficacy of ISBT-Bowen Therapy for patients with MPS. It alleviates pain, improves functional outcomes, enhances quality of life, and relieves mood symptoms.

The 50 most-cited articles on temporomandibular disorders: A bibliometric analysis

BACKGROUND

Temporomandibular disorders (TMD) are musculoskeletal conditions involving masticatory muscles and temporomandibular joints. Bibliometric analysis has been introduced as a new method for collecting and analyzing information on scientific articles.

OBJECTIVE

The aim of this study was to identify the 50 most cited articles on TMD, performing a bibliometric analysis of the identified papers to favor research and clinical practice.

METHODS

On December 17, 2021 a systematic research was performed to find all papers on TMD published in the literature. The Incites Journal Citation Reports dataset and Scopus database was used to obtain bibliometric indexes of the authors and metrics data of the journals, including Impact Factor, Eigenfactor Score, and Normalized Eigenfactor. VOSviewer was used to visualize the keyword mapping networking, with the nodes standing for keywords and the edges for keyword relationships.

RESULTS

Out of 24372 papers obtained by the search strategy, the 50 most cited articles on TMD were analyzed. The paper with the highest number of citations (n= 3020) was on TMD research diagnostic criteria. Rate of citations per year collected by the 50 most cited articles on TMD has been increasing over time (from 627 in 2006 to 1483 in 2021). Most of them were cross-sectional studies (n= 20; 40.0%) and narrative reviews (n= 14; 28.0%).

CONCLUSION

This bibliometric study showed an increasing number of citations for articles on TMD, testifying a high interest in the last years. Starting from this analysis, future studies might provide high-quality evidence on TMD management.

Efficacy of rehabilitation on reducing pain in muscle-related temporomandibular disorders: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Patients with temporomandibular disorders (TMD) mostly suffer from muscle-related pain. Several conservative interventions have been suggested as treatments for TMD in the last years.

OBJECTIVE

The aim of this systematic review with meta-analysis was to assess the efficacy of rehabilitative approaches in reducing pain in patients with muscle-related TMD.

METHODS

PubMed, Scopus, and Web of Science were systematically searched from inception until April 28th, 2021 to identify randomized controlled trials (RCTs) presenting: patients with painful muscle-related TMD; rehabilitative approaches as interventions; placebo or sham treatment as comparisons; pain intensity, using visual analogue scale as outcome. A meta-analysis was performed to evaluate the overall effect on painful muscle-related TMD patients. PROSPERO registration number of this systematic review is CRD42021251904.

RESULTS

Out of 1997 papers suitable for title/abstract screening, 189 articles were assessed for eligibility. Sixteen RCTs were included and most of them (n= 6, 37.5%) investigated the effects of the laser therapy. The meta-analysis revealed that rehabilitative interventions had a significant overall effect size (ES) of 1.44 (p< 0.0001) in decreasing pain in patients with muscle-related disorders.

CONCLUSION

Findings of this systematic review with meta-analysis suggested that rehabilitative approaches might be effective in reducing pain in muscle-related TMD patients. However, the low number of RCTs evaluating conservative approaches might impair the synthesis of evidence regarding the different techniques, calling for caution in the interpretation of these results.

Changes in Maximum Mandibular Mobility Due to Splint Therapy in Patients with Temporomandibular Disorders

Splint therapy is widely used in the treatment of myofascial pain, but valid studies on the efficacy of this therapy are rare. The purpose of the present study was to investigate which qualifiable and quantifiable effects of splint therapy are detectable. For this purpose, 29 patients (21 women, mean age 44.6 ± 16 years) diagnosed with myofascial pain (RDC/TMD) were investigated in this prospective clinical trial (10/6/14An). Patients were treated with Michigan splints applied overnight for three months. Before (T1) and after three months of treatment (T2), patients were registered with an electronic ultrasound device with qualitative and quantitative evaluation of the registrations and a qualitative assessment of pain symptoms using a verbal analog scale. Significant differences were found between maximum mouth opening (MMP) (p < 0.001) and right condylar movement (CM) at MMP (p = 0.045). Qualitative assessment revealed that 24 of 29 patients experienced an improvement in pain symptoms, 17 of whom experienced complete remission. The results of the qualitative and quantitative analysis provide indications of the effectiveness of the splint therapy. In addition to quantitative measurements, the ultrasound facebow technique was also able to provide qualitative information.

Local myalgia compared to myofascial pain with referral according to the DC/TMD: Axis I and II results

BACKGROUND

The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) categorized TMD muscle disorders into 3 subgroups: local myalgia, myofascial pain with spreading and myofascial pain with referral. However, the rationale for such division into subgroups and the pathogenesis and prognosis of muscle-related TMD are still poorly understood. The aim of this study was to explore the differences between local myalgia and myofascial pain with referral by means of a biopsychosocial model based on the DC/TMD.

METHODS

This retrospective study included all consecutive TMD patients who were diagnosed according to the DC/TMD in our institution between 2015 and 2018. The Axis I and II findings of patients diagnosed with local myalgia were compared to those of patients with myofascial pain with referral. A p value < 0.05 was considered statistically significant.

RESULTS

A total of 255 patients (61 men and 194 women, mean age 37.8 ± 15.34 years) were enrolled into the study, 114 in the local myalgia group and 83 in the myofascial pain with referral group. The levels of depression and nonspecific physical symptoms, headache attributed to TMD (HAattrTMD), and characteristic pain intensity (CPI) were significantly higher in the latter group. The significant differences for depression and nonspecific physical symptoms persisted after excluding patients diagnosed with HAattrTMD, however, the levels of significance were lower (p = 0.006 compared to p = 0.033 for depression total score, and p = 0.001 compared to p = 0.046 for nonspecific physical symptoms total score). CPI levels, extent of disability, and pain duration were similar for both groups when excluding for HAattrTMD.

CONCLUSION

The current study findings highlight the importance of differentiating between subgroups of myalgia according to the DC/TMD. The diagnosis of myofascial pain with referral may point to a significant Axis II component.

Re-Examining Myofascial Pain Syndrome: Toward Biomarker Development and Mechanism-Based Diagnostic Criteria

PURPOSE OF REVIEW

We discuss the need for a mechanism-based diagnostic framework with a focus on the development of objective measures (e.g., biomarkers) that can potentially be added to the diagnostic criteria of the syndrome. Potential biomarkers are discussed in relation to current knowledge on the pathophysiology of myofascial pain syndrome (MPS), including alterations in redox status, inflammation, and the myofascial trigger point (MTrP) biochemical milieu, as well as imaging and neurophysiological outcomes. Finally, we discuss the long-term goal of conducting a Delphi survey, to assess the influence of putative MPS biomarkers on clinician opinion, in order to ultimately develop new criteria for the diagnosis of MPS.

RECENT FINDINGS

Myofascial pain syndrome (MPS) is a prevalent healthcare condition associated with muscle weakness, impaired mood, and reduced quality of life. MPS is characterized by the presence of myofascial trigger points (MTrPs): stiff and discrete nodules located within taut bands of skeletal muscle that are painful upon palpation. However, physical examination of MTrPs often yields inconsistent results, and there is no gold standard by which to diagnose MPS. The current MPS diagnostic paradigm has an inherent subjectivity and the absence of correlation with the underlying pathophysiology. Recent advancements in ultrasound imaging, systemic biomarkers, MTrP-specific biomarkers, and the assessment of dysfunction in the somatosensorial system may all contribute to improved diagnostic effectiveness of MPS.

The effects of dry needling on pain relief and functional balance in patients with sub-chronic low back pain

BACKGROUND

Pain relief is important both for the movement of patients suffering from low back pain and the quality of life. Dry needling is effective on myofascial trigger points but its effect on the area of pain and the functional balance is not fully known.

OBJECTIVE

To examine the immediate effect of dry needling on pain and functional balance of patients suffering from low back pain.

METHODS

Twenty five patients with sub-chronic low back pain were randomly divided into two groups: the intervention or control group. Needles were used for the participants of the intervention group, bilaterally at the spinus level, one and a half finger breath from the midline in levels L2-L5 of the lumbar spine. A third line of needles was inserted in the interspinosus spaces, except L5-S1 level. Bipedal stance, lateral loading and mediolateral body sway were assessed using a pair of force plates. Pain tolerance was assessed using an algometer.

RESULTS

The pain tolerance significantly increased in the intervention group from (M = 4.87, SE 0.663) to (M = 6.52, SE 0.547) (F(1,23) = 7.8, p< 0.05) after intervention. During mediolateral body sway the force signal in the dominant frequency significantly increased in the intervention group from (M = 43.2, SE 4.6) to (M = 54,9, SE 3.6) (F(1,23) = 4.63, p< 0.05) after intervention, exhibiting more controlled rhythmic behavior.

CONCLUSIONS

Dry needling in painful areas and penetrating all the muscle groups seems to improve pain and functional balance, yet its effect on specific muscles needs to be studied further.

Are occlusal splints effective in reducing myofascial pain in patients with muscle-related temporomandibular disorders? A randomized-controlled trial

Objectives

This study aims to evaluate the effectiveness of upper Michigan occlusal splint (OS) compared to mandibular OS in terms of pain, range of motion (ROM), and muscle activity as assessed by surface electromyography (sEMG) in patients affected by muscle-related temporomandibular disorders (TMD).

Patients and methods

In this randomized-controlled trial, a total of 40 adult patients (13 males, 27 females; mean age: 47.2±12.8 years; range, 22 to 56 years) with a diagnosis of myofascial pain, lasting from at least three months on at least one masseter muscle. The patients were randomly allocated into two groups: Group 1 (n=20) using upper Michigan OS and Group 2 (n=20) using mandibular OS. At baseline (T0), at one (T1), three (T2), and six months (T3), the following outcomes were assessed: myofascial pain by Visual Analog Scale (VAS) and ROM of mandible movements, activity of the main masticatory muscles through sEMG.

Results

There were no significant intra-group differences in the outcome measures assessed in both groups. However, Group 2 had a significantly higher right lateral mandibular ROM at T2 (7.1±3.1 vs. 9.8±2.3, respectively; p<0.05) and a significantly higher left lateral mandibular ROM at T3 (7.6±3.5 vs. 10.5±2.1, respectively; p<0.05). We found no significant difference in none of the sEMG parameters.

Conclusion

Our study results suggest that OS, independently from being built on the upper or lower arch, seems to not have significant effects in reducing pain over a six-month period in TMD patients.

Evaluation of Soft Tissue Mobilization in Patients with Temporomandibular Disorder-Myofascial Pain with Referral

The aim of the study was functional evaluation of soft tissue mobilization in patients with temporomandibular disorder-myofascial pain with referral. The study group consisted of 50 individuals-37 females and 13 males. The average age was 23.36 ± 2.14 years. All subjects were diagnosed with myofascial pain with referral (diagnostic criteria for temporomandibular disorders). Soft tissue mobilization was applied three times. Electromyography of selected masticatory muscles was performed six times-before and after the treatment. After each mobilization, a decreasing tendency of muscular activity was observed in the entire study group. The Friedman test indicated that mobilization altered the activity of the right temporal muscle (p = 0.00010), both masseters (p = 0.0000), right sternocleidomastoid (p = 0.00251), left sternocleidomastoid (p = 0.00033), and right and left digastric muscles (p = 0.00045 and p = 0.00000, respectively). With respect to symmetry a statistically significant difference was noted in the case of the sternocleidomastoid muscles (p = 0.00729). In conclusion, soft tissue mobilization seems to be effective in the relaxation of masticatory muscles in patients with temporomandibular disorders. Our findings proved that soft tissue mobilization does not improve the symmetry and synergy of the masticatory muscles limited by dental occlusion.

Dry Needling and Photobiomodulation Decreases Myofascial Pain in Trapezius of Women: Randomized Blind Clinical Trial

OBJECTIVE

The purpose of this study was to assess whether dry needling (DN) added to photobiomodulation (PBM) has effects on the treatment of active myofascial trigger points in the upper trapezius.

METHODS

This study was a randomized clinical trial, with 43 participants divided into 3 groups: DN and PBM (DNP), DN, and DN outside of the trigger point (DNout). Each group received 1 session of DN followed by PBM therapy with the machine turned on or off. Pain, disability, pain pressure threshold, and muscle activity were assessed before the intervention and afterward at intervals of 10 minutes, 30 minutes, 1 week, and 1 month.

RESULTS

Pain decreased after intervention in the DNP and DNout groups, with mean differences, respectively, of 1.33 cm (95% confidence interval [CI], 0.019-2.647) and 2.78 cm (95% CI, 1.170-2.973). Scores for the disability questionnaire decreased in all groups after intervention (F = 36.53, P < .0001) after the intervention, with mean differences of 3.8 points in the DNP group (95% CI, 1.082-5.518), 3.57 in the DN group (95% CI, 0.994-6.149), and 5.43 in the DNout group (95% CI, 3.101-7.756). There were no significant differences between or within groups in pain pressure threshold (F = 2.14, P = .139), with mean differences after 30 minutes of 0.139 kgf for the DNP group (95% CI, -0.343 to 0.622), 0.273 for the DN group (95% CI, -0.661 to 1.209), and -0.07 for the DNout group (95% CI, -0.465 to 0.324). Muscle activation for the DN group increased 8.49% after the intervention, where for the DNP group it decreased 11.5%, with a significant difference between groups.

CONCLUSION

DN added to PBM presented similar results compared to DNout and DN. In this sample, the effects of the application of DN outside of the trigger point had better effects on pain and disability scores than DN applied directly on the trigger point.

Comparative Effectiveness of Thai Herbal Formula (Thor-Ra-Nee-San-Tha-Kat) Versus Naproxen for Chronic Myofascial Pain: A Pilot Randomized-Controlled Trial

Background: Myofascial pain syndrome (MPS) is a painful musculoskeletal condition. The prevalence of MPS ranges from 5.9% to 38.7% in the general population. "Thor-ra-nee-san-tha-kat" (TRK) is a traditional formula included in the Thailand National List of Essential Medicines for the treatment for muscle pain caused by abdominal rigidity and for severe constipation. Objectives: The authors employed a pilot single-blind, randomized-controlled trial to compare the effectiveness of TRK and naproxen for the treatment of chronic upper trapezius MPS. Materials and Methods: Seventy-six male and female subjects, ages 25-55 years, who met the inclusion criteria were equally randomized into two groups to receive either two 500 mg capsules of TRK once daily before bed or two 250 mg naproxen tablets twice a day after meals for 14 days. Subjects assessed their level of pain using the numerical rating scale. Cervical range of motion (CROM) was determined using a goniometer, and pressure pain threshold (PPT) was assessed using an algometer. Adverse drug reactions were recorded and all items were compared within and between groups, before and after treatment. Results: The results revealed that patient pain scores after 14 days of treatment were much improved with mean differences exceeding the reference minimum clinically important difference (MCID) in both groups. However, the changes in CROM and PPT values were small and did not surpass their respective reference MCIDs except for the right lateral bending CROM for naproxen treatment. The adverse drug reactions were mild, with watery stools reported by 47% of patients in the TRK-treated group and constipation reported by 24% of those in the naproxen group. Conclusion: The administration of TRK formula for 14 days was safe and as effective as naproxen at providing short-term relief of pain in patients with chronic upper trapezius pain.

Evaluation of the Combination of Muscle Energy Technique and Trigger Point Therapy in Asymptomatic Individuals with a Latent Trigger Point

(1) Background: The aim of the study was to determine the effect of the combination therapy of Muscle Energy Technique (MET) and Trigger Point Therapy (TPT) on the angular values of the range of movements of the cervical spine and on the pressure pain threshold (PPT) of the trapezius muscle in asymptomatic individuals. METHODS: The study involved 60 right-handed, asymptomatic students with a latent trigger point in the upper trapezius muscle. All qualified volunteers practiced amateur symmetrical sports. The study used a tensometric electrogoniometer (cervical spine movement values) and an algometer (pressure pain threshold (PPT) of upper trapezius). Randomly (sampling frame), volunteers were assigned to three different research groups (MET + TPT, MET and TPT). All participants received only one therapeutic intervention. Measurements were taken in three time-intervals (pre, post and follow-up the next day after therapy). (2) Results: One-time combined therapy (MET + TPT) significantly increases the range of motion occurring in all planes of the cervical spine. One-time treatments of single MET and single TPT therapy selectively affect the mobility of the cervical spine. The value of the PPT significantly increased immediately after all therapies, but only on the right trapezius muscle, while on the left side only after the therapy combining MET with TPT. (3) Conclusion: The MET + TPT method proved to be the most effective, as it caused changes in all examined goniometric and subjective parameters.

Ultrasound-Guided Physiological Saline Injection for Patients with Myofascial Pain

Background:

Based on the histological confirmation of the presence of nerve structure in the fascia, hence, myofascial pain was treated by the mechanism referred to as interfascial block. To date, the studies of physiological saline for treating patients with myofascial pain has been limited. Ultrasound (US) guided with physiological saline injection (PSI) technique has been routinely practiced among patients with myofascial pain in outpatient service at the Department of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital. The main objective of this present study is to find the overview data including the percentage of patients responding, acceptable pain period, and adverse events.

Materials and Methods:

Electronic medical reports among 142 patients receiving US-guided PSI from August 1, 2016, to November 20, 2017, at the Department of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital, were retrospectively reviewed by the first author. Procedures were performed by the last author. The analysis was independently performed by the first author.

Results:

One hundred and forty-two patients with complete medical records were compatible with analysis. The average age of patients was 55 years. Most of the patients were female (68.3%). Most of the patients (76.8%) had chronic suffering from myofascial pain. Approximately half of the patients (56.4%) are currently received pain-relieving medications. Upper trapezius muscle (19.5%) was the most common muscle receiving the procedure, followed by multifidus (10.0%) and quadratus lumborum (9.5%). Most of the patients (86.8%) received the procedure one muscle. Approximately 30% of the patients were able to stop pain-relieving medications after the procedure. The median of acceptable pain period was 63 days. The percentage of patients having an acceptable pain period >3 months was 43.9%. No major adverse events were demonstrated.

Conclusion:

US-guided PSI technique demonstrated pain reduction in 72.8% of the analyzed patients, with an acceptable pain period of 63 days. No major adverse events were demonstrated among all the patients. This technique should be considered as another invasive procedure for eradication myofascial trigger point.

Theory and usage of tensiomyography and the analysis method for the patient with low back pain

Tensiomyography (TMG) is an injury detecting tool for muscle group imbalances and/or side-to-side asymmetries. It is liable to detect to measure contractile properties and mechanical responses based on muscle belly displacement. Although other previous papers have well suggested the methods for examining the several muscle groups using TMG, a detecting method for the imbalances in low back muscles has not been investigated, and no review papers have been compiled. Therefore, this study aimed to synthesize the theories of the previous studies observed using TMG and to briefly summarize its usefulness by performing simple experiments on the left and right regions of the erector spinae muscles, which may be a problem using TMG for patients with low back pain.

Transcutaneous Electrical Nerve Stimulation on Acupuncture Points Improves Myofascial Pain, Moods, and Sleep Quality

PURPOSE

The aim of this study was to evaluate the effects of transcutaneous electrical nerve stimulation at acupuncture points versus trigger points on myofascial pain, moods, and sleep quality.

DESIGN

A randomized controlled study recruited 64 patients with spinal cord injury with myofascial pain.

METHODS

Outcomes of pain, moods, and sleep quality were measured and analyzed by the generalized estimation equation, analysis of covariance, and paired t test. Transcutaneous electrical nerve stimulation was applied for seven consecutive days at Hegu (LI4) and Daling (PC7) acupuncture points or myofascial trigger points.

FINDING

Significant differences were found in pain intensity from Day 3 forward, after controlling for confounders. Significant within-group differences were found in pain, moods, and sleep quality.

CONCLUSIONS

Transcutaneous electrical nerve stimulation at acupuncture and trigger points effectively improved pain, moods, and sleep quality in patients with spinal cord injury with myofascial pain. Acupuncture points had superior improvement in pain intensity and slight improvement in sleep quality than did trigger points.

CLINICAL RELEVANCE

Transcutaneous electrical nerve stimulation at acupuncture points could be applied for improving myofascial pain.

Reliability and validity of clinical tests to assess posture, pain location, and cervical spine mobility in adults with neck pain and its associated disorders: Part 4. A systematic review from the cervical assessment and diagnosis research evaluation (CADRE) collaboration

PURPOSE

To determine the reliability and validity of clinical tests to assess posture, pain location, and cervical spine mobility in adults with grades I-IV neck pain and associated disorders (NAD).

METHODS

We systematically searched electronic databases to update the systematic review of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders. Eligible reliability and validity studies were critically appraised using modified versions of the QAREL and QUADAS-2 instruments, respectively. Evidence from low risk of bias studies were synthesized following best evidence synthesis principles.

RESULTS

We screened 14302 articles, critically appraised 46 studies, and found 32 low risk of bias articles (14 reliability and 18 validity studies). We found preliminary evidence of: 1) reliability of visual inspection, aided with devices (CROM and digital caliper) to assess head posture; 2) reliability and validity of soft tissue palpation to locate tender/trigger points in muscles; 3) reliability and validity of joint motion palpation to assess stiffness and pain provocation in combination; and 4) range of motion tests using visual estimation (in cervical extension only) or devices (digital caliper, goniometer, inclinometer) to assess cervical mobility.

CONCLUSIONS

We found little evidence to support the reliability and validity of clinical tests to assess head posture, pain location and cervical mobility in adults with NAD grades I-III. More advanced validity studies are needed to inform the clinical utility of tests used to evaluate patients with NAD.

Dry Needling on the Infraspinatus Latent and Active Myofascial Trigger Points in Older Adults With Nonspecific Shoulder Pain: A Randomized Clinical Trial

BACKGROUND AND PURPOSE

Shoulder pain is a prevalent condition in older adults. Some authors associate nonspecific shoulder pain with myofascial trigger points (MTrPs) in the infraspinatus muscle. Dry needling is recommended to relieve the MTrP pain of shoulders in the short term (<9 days). Active MTrPs dry needling improves shoulder pain and the irritability of the satellite MTrPs in the referred pain area. Nociceptive activity at a latent MTrP may influence motor activity and the sensitivity of MTrPs in distant muscles at a similar segmental level. Therefore, this study aimed to evaluate dry needling on 1 latent MTrP, in conjunction with 1 active MTrP, in the infraspinatus muscle of older adults with nonspecific shoulder pain.

METHODS

A single-center, randomized, single-blinded, controlled study (NCT02032602) was carried out. Sixty-six patients aged 65 years and older with trigger points in the ipsilateral infraspinatus of the painful shoulder were randomly assigned to (1) of (2) treatment groups. A session of dry needling on the infraspinatus was performed in (1) the most hyperalgesic active and latent MTrP or (2) only the most hyperalgesic active MTrP. The Numeric Rating Scale, the pressure pain threshold (primary outcome) on the anterior deltoid and extensor carpi radialis brevis latent MTrPs, and grip strength were assessed before, after, and 1 week after the intervention.

RESULTS

Statistically significant differences in the reduction of pain intensity (P ≤ .001; η = 0.159-0.269; d = 1.017-1.219) and the increase of pressure pain threshold (P < .001; η = 0.206-0.481; d = 0.870-1.924) were found for the (1) treatment group immediately and 1 week postintervention. Nevertheless, no statistical significant differences were found in grip strength (P >. 05; η = 0.006-0.033; d = 0.158-0.368).

CONCLUSIONS

One dry needling intervention of the latent MTrP associated with the key active MTrP of the infraspinatus reduces pain intensity and the irritability of the satellite MTrPs located in the referred pain area in the short term in older adults with nonspecific shoulder pain.

Comparing Trigger Point Dry Needling and Manual Pressure Technique for the Management of Myofascial Neck/Shoulder Pain: A Randomized Clinical Trial

OBJECTIVE

The aim of this study was to investigate short-term and long-term treatment effects of dry needling (DN) and manual pressure (MP) technique with the primary goal of determining if DN has better effects on disability, pain, and muscle characteristics in treating myofascial neck/shoulder pain in women.

METHODS

In this randomized clinical trial, 42 female office workers with myofascial neck/shoulder pain were randomly allocated to either a DN or MP group and received 4 treatments. They were evaluated with the Neck Disability Index, general numeric rating scale, pressure pain threshold, and muscle characteristics before and after treatment. For each outcome parameter, a linear mixed-model analysis was applied to reveal group-by-time interaction effects or main effects for the factor "time."

RESULTS

No significant differences were found between DN and MP. In both groups, significant improvement in the Neck Disability Index was observed after 4 treatments and 3 months (P < .001); the general numerical rating scale also significantly decreased after 3 months. After the 4-week treatment program, there was a significant improvement in pain pressure threshold, muscle elasticity, and stiffness.

CONCLUSION

Both treatment techniques lead to short-term and long-term treatment effects. Dry needling was found to be no more effective than MP in the treatment of myofascial neck/shoulder pain.

Relationship between Alexithymia and latent trigger points in the upper Trapezius

Background

Latent trigger points (LTrPs) can be activated by future events, leading to pain. Few studies have reported LTrP risk factors. It has been suggested that alexithymia is associated with myofascial pain and diminished awareness of physical sensation. This study was designed to evaluate the relation between alexithymia and LTrPs found the upper trapezius of healthy individuals.

Methods

The correlation between LTrPs and alexithymia, and between LTrPs and depression was analyzed in 160 healthy participants (80 male, mean age: 40.5 years [20 to 66 years]). Each participant was evaluated for potential LTrPs by careful manual examination and completed the Toronto Alexithymia Scale-20 (TAS-20) and the Beck Depression Inventory (BDI) to assess potential alexithymia and depressive symptoms, respectively.

Results

LTrPs were observed in the upper trapezius of 76 participants (47.5%). TAS-20 scores were significantly higher in subjects with LTrPs than without LTrPs (p < 0.001); in contrast, there was no significant BDI score difference between these groups (p = 0.451). The LTrP risk for alexithymia was 2.74 (95% confidence interval [95% CI]: 2.10–3.58). There was no correlation between the TAS-20 and BDI scores (correlation coefficient: −0.04). Significant risk factors associated with LTrPs included the TAS-20 score (odds ratio [OR]: 1.11, 95% CI: 1.07–1.15) and age (OR: 1.05, 95% CI: 1.01–1.09).

Conclusions

Alexithymia was associated with LTrPs in the upper trapezius of healthy individuals, suggesting that it may serve as a useful predictive factor.

Trial registration

UMIN000027468. Registered 23 May 2017(retrospectively registered).

A Multimodal Approach for Myofascial Pain Syndrome: A Prospective Study

OBJECTIVE

The purpose of this study was to analyze pain intensity in patients with myofascial pain syndrome (MPS) following a multimodal rehabilitation protocol.

METHODS

A prospective study was carried out following the Template for Intervention Description and Replication criteria. Patients were recruited from the rehabilitation unit of a university hospital in Spain between 2009 and 2013. Patients were included if they had a medical diagnosis of MPS in any of the following regions: cervicobrachial (n = 102), lumbosacral (n = 30), elbow (n = 14), ankle and foot (n = 10), and temporomandibular jaw (n = 1). The multimodal rehabilitation protocol included myofascial trigger point dry needling, spray and stretching, Kinesio taping, eccentric exercise, and patient education. The protocol was applied for 4 weeks (5 sessions) for the active and/or latent myofascial trigger points in each body region. Pain intensity was measured by using the visual analog scale (VAS) immediately before beginning of the study and 1 week after completion of the protocol.

RESULTS

The study sample comprised 150 patients (mean ± standard deviation age, 51.5 ± 1.19 years). Statistically significant differences were obtained for reduction in pain intensity (4 ± 2.03; P = .002). Clinically relevant reductions (VAS ≥30 mm; P < .001) were obtained in 78.7% of the interventions. Four treatment sessions reduced the VAS score by 10 mm in 83.55% of the sample. There were no statistically significant differences (P = .064) for reduction in pain intensity in the different body regions.

CONCLUSIONS

A multimodal rehabilitation protocol showed clinically relevant differences in the reduction in pain intensity in different body regions in patients with MPS.

Efficacy of quadriceps vastus medialis dry needling in a rehabilitation protocol after surgical reconstruction of complete anterior cruciate ligament rupture

BACKGROUND

Several new rehabilitation modalities have been proposed after anterior cruciate ligament (ACL) reconstruction. Among these, trigger point dry needling (TrP-DN) might be useful in the treatment of myofascial pain syndrome associated with ACL reconstruction to reduce pain intensity, increase knee flexion range and modify the mechanical properties of the quadriceps muscle during late-stage rehabilitation. To date, this is the first randomized clinical trial to support the use of TrP-DN in the early rehabilitation process after ACL reconstruction. The aim of this study was to determine the pain intensity, range of motion (ROM), stability, and functionality improvements by adding quadriceps vastus medialis TrP-DN to the rehabilitation protocol (Rh) provided to subacute ACL reconstructed patients.

METHODS

This randomized, single-blinded, clinical trial (NCT02699411) included 44 subacute patients with surgical reconstruction of complete ACL rupture. The patients were randomized into 2 intervention groups: Rh (n = 22) or Rh + TrP-DN (n = 22). Pain intensity, ROM, stability, and functionality were measured at baseline (A0) and immediately (A1), 24 hours (A2), 1 week (A3), and 5 weeks (A4) after the first treatment.

RESULTS

Comparing statistically significant differences (P ≤ .001; Eta = 0.198-0.360) between both groups, pain intensity (at A1), ROM (at A1, A2, and A3), and functionality (at A2, A3, and A4) were increased. Nevertheless, the rest of measurements did not show significant differences (P > .05).

CONCLUSION

Quadriceps vastus medialis TrP-DN in conjunction with a rehabilitation protocol in subacute patients with surgical reconstruction of complete ACL rupture increases ROM (short-term) and functionality (short- to mid-term). Although there was an increase in pain intensity with the addition of TrP-DN, this was not detected beyond immediately after the first treatment. Furthermore, stability does not seem to be modified after TrP-DN.

Dry Needling Combined With Physical Therapy in Patients With Chronic Postsurgical Pain Following Total Knee Arthroplasty: A Case Series

Study Design Case series. Background This case series describes a combined program of dry needling and therapeutic exercise in a small group of patients with persistent pain following total knee arthroplasty (TKA). Case Description Fourteen patients who underwent TKA had persistent postsurgical pain and myofascial trigger points that were nonresponsive to treatment with conventional physical therapy and/or medication. The patients received a weekly dry needling treatment in combination with therapeutic exercises for 4 weeks. Pain perception was assessed preintervention and postintervention with a visual analog scale and function was assessed with the Western Ontario and McMaster Universities Osteoarthritis Index, 6-minute walk test, timed up-and-go test, 30-second chair-stand test, and knee joint range of motion. Outcomes After TKA, the patients had a mean ± SD symptom duration of 6.3 ± 3.1 months. Subsequent to dry needling, patients reported a significant mean ± SD decrease in pain intensity from 55.6 ± 6.6 to 19.3 ± 5.6 (P<.001) and improvements in Western Ontario and McMaster Universities Osteoarthritis Index scores from 10.1 ± 0.8 to 4.9 ± 1.0 for pain (P<.001), from 5.3 ± 0.4 to 2.4 ± 1.2 for stiffness (P<.001), and from 36.7 ± 2.0 to 20.1 ± 3.2 for function (P<.001). Knee flexion increased from a mean ± SD of 82.7° ± 5.2° to 93.3° ± 4.3° (P<.001), and joint extension improved from 15.8° ± 2.9° to 5.3° ± 2.4° (P<.05). The 6-minute walk test also showed improvement in postintervention values from a mean ± SD of 391.4 ± 23.7 to 424.7 ± 28.4 m (P<.05). Discussion After dry needling combined with therapeutic exercises, patients who had chronic pain following TKA showed clinically significant improvements in pain, range of motion, function, and myofascial trigger points. Future randomized clinical trials should further investigate the effectiveness of this protocol under similar conditions. Level of Evidence Therapy, level 4. J Orthop Sports Phys Ther 2017;47(3):209-216. Epub 3 Feb 2017. doi:10.2519/jospt.2017.7089.

Tensiomyography, sonoelastography, and mechanosensitivity differences between active, latent, and control low back myofascial trigger points: A cross-sectional study

The myofascial pain syndrome (MPS) is considered the most common musculoskeletal condition. The lumbopelvic pain (LPP) is established as one of the most prevalent musculoskeletal disorders. Nevertheless, previous research has not yet studied the contractibility changes by tensiomyography between myofascial trigger point (MTrP) types and normal tissue. Therefore, the aim of this study was to determine the tensiomyography, sonoelastography, and pressure pain threshold (PPT) differences between the palpation area of active and latent MTrPs with regards to control points in the lumbar erector spinae muscles of subjects with LPP. A cross-sectional descriptive study was performed. A convenience sample of 60 points (20 active MTrPs, 20 latent MTrPs, and 20 control points) was registered bilaterally in the lumbar erector spinae muscles from subjects with nonspecific LPP. The palpation order of active MTrPs, latent MTrPs, or control points was randomized for each side. The outcome assessors were blinded to the order or point type. The outcome measurements order for each point was sonoelastography manual strain index, tensiomyography, and PPT, separated by 15 minutes. Five contractile objective parameters were: maximal radial displacement (Dm), contraction time (Tc), sustain time (Ts), delay time (Td), and half-relaxation time (Tr). Tensiomyography parameters did not show any statistically significant difference (P > 0.05) between active MTrPs, latent MTrPs, and control points. Nevertheless, PPT and sonoelastography showed statistically significant differences (P < 0.05) between all point types, except for active and latent MTrPs PPT comparison (P = 0.091). Regarding the active MTrPs, a moderate positive correlation was observed between PPT and Dm (P = 0.047; τB = 0.450). Considering the control points, a moderate positive correlation was shown between sonoelastography and Td (P = 0.044; τB = 0.328). The tensiomyography contractile properties did not seem to show differences, while the sonoelastography and mechanosensitivity presented a higher stiffness and a lower PPT, respectively, between the palpation area of active and latent MTrPs with regards to control points in the lumbar erector spinae muscles of subjects with LPP. Considering the correlations, further research is needed regarding the muscle contractile properties modifications under MPS treatments, especially Dm in active MTrPs and Td in normal sites.

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.

Beneficial Effects of Dry Needling for Treatment of Chronic Myofascial Pain Persist for 6 Weeks After Treatment Completion

BACKGROUND

Dry needling is an effective treatment for reducing pain associated with active myofascial trigger points (a-MTrPs) in the short term. The duration of the benefits of this treatment have not been fully assessed.

OBJECTIVE

To determine whether the benefits of dry needling (DN) of a-MTrPs are sustained 6 weeks posttreatment.

DESIGN

Follow-up of a prospective study.

SETTING

University.

PARTICIPANTS

A total of 45 patients (13 male and 32 female) with cervical pain >3 months and a-MTrPs in the upper trapezius who completed 3 DN treatments and who were evaluated 6 weeks posttreatment.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Primary outcomes were changes from baseline to follow-up in scores for the verbal analogue scale (VAS), Brief Pain Inventory (BPI), and MTrP status. MTrPs were rated as active (spontaneously painful), latent (painful only on compression), and nonpalpable nodule. Responders were patients whose MTrP status changed from active to latent or nonpalpable nodule (resolved). Secondary outcomes were pain pressure threshold (PPT), Profile of Mood States, Oswestry Disability Index (ODI), MOS 36-Item Short-Form Health Survey (SF-36), and cervical range of motion.

RESULTS

Pain measures remained significantly improved 6 weeks posttreatment (P < .003), as did the SF-36 physical functioning score (0.01) and ODI (P = .002). Side bending and PPT for subjects with unilateral MTrPs had sustained improvement (P = .002). The number of subjects with sustained MTrP response at 6 weeks was significant (P < .001). Comparing responders to nonresponders, the changes in VAS and BPI were statistically significant (P = .006, P = .03) but the change in PPT was not. Patients with higher baseline VAS scores had a higher risk of not responding to DN; those with a greater drop in VAS score from baseline had a higher probability of sustained response. A 1-unit decrease in VAS at baseline resulted in a 6.3-fold increase in the odds of being a responder versus a nonresponder (P = .008).

CONCLUSIONS

In this study, there was sustained reduction of pain scores after completion of DN, which is more likely with a greater drop in VAS score. Patients with higher baseline VAS scores are less likely to respond to DN. Early intervention toward significant pain reduction is likely to be associated with sustained clinical response.

LEVEL OF EVIDENCE

IV.

Botulinum toxin type A for the treatment of head and neck chronic myofascial pain syndrome: A systematic review and meta-analysis

BACKGROUND

The authors conducted a systematic review to study the efficacy of botulinum toxin type A (BoTN-A) in the treatment of myofascial pain syndrome.

TYPES OF STUDIES REVIEWED

The authors identified randomized, double-masked, placebo-controlled studies on June 1, 2016, from PubMed, Web of Science, and the Cochrane Library. Three of the authors assessed the studies for risk of bias. Outcomes included pain reduction on a visual analog scale, the number of responders, and the posttreatment pain threshold to applied pressure using algometry.

RESULTS

The initial search strategy yielded 253 unduplicated references, which the authors reduced to 13 relevant studies. The authors included 11 studies in the meta-analyses as the investigators of those studies had reported similar outcomes. Pooled results showed a nonsignificant improvement in the posttreatment intensity of pain in the BoTN-A group compared with the placebo group at 4 to 6 weeks (standardized difference in means [SDM], -0.110; 95% confidence interval [CI], -0.344 to 0.124; P = .356) and a significant improvement at 2 to 6 months (SDM, -0.360; 95% CI, -0.623 to -0.096; P = .008). The number of study participants who responded to treatment was not statistically significantly different between the groups (risk ratio, 1.346; 95% CI, 0.922-1.964; P = .123) nor was the increase of pain threshold to pressure (algometry) at 2 months (SDM, 0.131; 95% CI, -0.178 to 0.440; P = .405). The study investigators reported no major adverse events.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Pain was reduced significantly in the group that received BoTN-A compared with the placebo group at 2 to 6 months but not at 4 to 6 weeks (with moderate quality of the evidence). Additional studies with larger numbers of participants are needed to confirm these results.

DRY NEEDLING IN SUBJECTS WITH MUSCULAR TRIGGER POINTS IN THE LOWER QUARTER: A SYSTEMATIC REVIEW

BACKGROUND

Trigger points, which have been defined as highly localized, hyperirritable locations in a palpable taut band of skeletal muscle fibers, have been identified with a variety of musculoskeletal conditions. The incidence of trigger point pain is high, with studies showing them as the primary source of pain in 30-85% of patients presenting in a primary care setting or pain clinic. Dry needling has emerged as a possible intervention for trigger points, but its effectiveness has not yet fully been determined.

PURPOSE

To assess and provide a summary on the current literature for the use of dry needling as an intervention for lower quarter trigger points in patients with various orthopedic conditions.

STUDY DESIGN

Systematic review.

METHODS

CINAHL, NCBI-PubMed, PEDro, SPORTDiscus, Cochrane Library, and APTA's PTNow were searched to identify relevant randomized controlled trials. Six studies meeting the inclusion criteria were analyzed using the PEDro scale.

RESULTS

Four of the studies assessed by the PEDro scale were deemed 'high' quality and two were 'fair' quality. Each of the six included studies reported statistically significant improvements with dry needling for the reduction of pain intensity in the short-term. Only one study reported a statistically significant improvement in short-term functional outcomes; however, there was no maintenance of improved function at long-term follow-up. Furthermore, none of the studies reported statistically significant changes regarding the effect of dry needling on quality of life, depression, range of motion, or strength.

CONCLUSION

A review of current literature suggests that dry needling is effective in reducing pain associated with lower quarter trigger points in the short-term. However, the findings suggest that dry needling does not have a positive effect on function, quality of life, depression, range of motion, or strength. Further high quality research with long-term follow-up investigating the effect of dry needling in comparison to and in conjunction with other interventions is needed to determine the optimal use of dry needling in treating patients with lower quarter trigger points.

LEVELS OF EVIDENCE

1.

Novel Use of Ultrasound Elastography to Quantify Muscle Tissue Changes After Dry Needling of Myofascial Trigger Points in Patients With Chronic Myofascial Pain

OBJECTIVES

To compare a mechanical heterogeneity index derived from ultrasound vibration elastography with physical findings before and after dry-needling treatment of spontaneously painful active myofascial trigger points in the upper trapezius muscle.

METHODS

Forty-eight patients with chronic myofascial pain enrolled in a prospective interventional trial of 3 weekly dry-needling treatments for active myofascial trigger points. Trigger points were evaluated at baseline and at treatment completion using palpation, the pressure-pain threshold, and the mechanical heterogeneity index. Thirty patients were reevaluated at 8 weeks. Trigger points that "responded" changed to tissue that was no longer spontaneously painful, with or without the presence of a palpable nodule. Trigger points that "resolved" changed to tissue without a palpable nodule. The mechanical heterogeneity index was defined as the proportion of the upper trapezius muscle that appeared mechanically stiffer on elastography. Statistical significance for comparisons was determined at P < .05.

RESULTS

Following 3 dry needle treatments, the mechanical heterogeneity index decreased significantly for the 38 myofascial trigger points (79% of 48) that responded to treatment. Among these, the baseline mechanical heterogeneity index was significantly lower for the 13 trigger points (27% of 38) that resolved, but the decrease after 3 dry needle treatments did not reach significance. The pressure-pain threshold improved significantly for both groups. At 8 weeks, the mechanical heterogeneity index decreased significantly for the 22 trigger points (73% of 30) that responded and for the 10 (45% of 22) that resolved. The pressure-pain threshold improvement was significant for trigger points that responded but did not reach significance for resolved trigger points.

CONCLUSIONS

The mechanical heterogeneity index identifies changes in muscle tissue properties that correlate with changes in the myofascial trigger point status after dry needling.

Myofascial Trigger Points Then and Now: A Historical and Scientific Perspective

The intent of this article is to discuss the evolving role of the myofascial trigger point (MTrP) in myofascial pain syndrome (MPS) from both a historical and scientific perspective. MTrPs are hard, discrete, palpable nodules in a taut band of skeletal muscle that may be spontaneously painful (i.e., active) or painful only on compression (i.e., latent). MPS is a term used to describe a pain condition that can be acute or, more commonly, chronic and involves the muscle and its surrounding connective tissue (e.g. fascia). According to Travell and Simons, MTrPs are central to the syndrome-but are they necessary? Although the clinical study of muscle pain and MTrPs has proliferated over the past two centuries, the scientific literature often seems disjointed and confusing. Unfortunately, much of the terminology, theories, concepts, and diagnostic criteria are inconsistent, incomplete, or controversial. To address these deficiencies, investigators have recently applied clinical, imaging (of skeletal muscle and brain), and biochemical analyses to systematically and objectively study the MTrP and its role in MPS. Data suggest that the soft tissue milieu around the MTrP, neurogenic inflammation, sensitization, and limbic system dysfunction may all play a role in the initiation, amplification, and perpetuation of MPS. The authors chronicle the advances that have led to the current understanding of MTrP pathophysiology and its relationship to MPS, and review the contributions of clinicians and researchers who have influenced and expanded our contemporary level of clinical knowledge and practice.

Signs and Symptoms of Myofascial Pain: An International Survey of Pain Management Providers and Proposed Preliminary Set of Diagnostic Criteria

OBJECTIVE

Myofascial Pain Syndrome (MPS) is highly prevalent in pain medicine, yet there is no "gold standard" or set of validated diagnostic criteria for clinical or research use. A survey collected clinician perspectives on MPS to foster the development of a formal case definition for empirical validation.

DESIGN

International survey.

METHODS

Clinician members of the International Association for the Study of Pain and the American Academy of Pain Medicine received a survey of the symptoms and signs of MPS and expected response to treatment. Write-in fields were available for each category and to suggest relevant diagnostic studies.

RESULTS

Two hundred fourteen responses were received from 4,143 surveys mailed. The most essential components of MPS were tender spots that recreate symptoms when palpated. MPS was also associated with muscle stiffness, decreased range of motion of the affected joints, worsening symptoms with stress, palpable taut band or tender nodule, and referred pain with palpation of the tender spot. Diagnostic studies are reported to be useful for ruling out other pathology, but not to confirm the presence of the condition.

CONCLUSIONS

These results were used to propose a set of preliminary diagnostic criteria; expert consensus for case definition and subsequent empirical validation are required for standardization in research and clinical management of MPS.

Two-dimensional ultrasound and ultrasound elastography imaging of trigger points in women with myofascial pain syndrome treated by acupuncture and electroacupuncture: a double-blinded randomized controlled pilot study

Chronic pain has been often associated with myofascial pain syndrome (MPS), which is determined by myofascial trigger points (MTrP). New features have been tested for MTrP diagnosis. The aim of this study was to evaluate two-dimensional ultrasonography (2D US) and ultrasound elastography (UE) images and elastograms of upper trapezius MTrP during electroacupuncture (EA) and acupuncture (AC) treatment. 24 women participated, aged between 20 and 40 years (M ± SD = 27.33 ± 5.05) with a body mass index ranging from 18.03 to 27.59 kg/m2 (22.59 ± 3.11), a regular menstrual cycle, at least one active MTrP at both right (RTPz) and left trapezius (LTPz) and local or referred pain for up to six months. Subjects were randomized into EA and AC treatment groups and the control sham AC (SHAM) group. Intensity of pain was assessed by visual analogue scale; MTrP mean area and strain ratio (SR) by 2D US and UE. A significant decrease of intensity in general, RTPz, and LTPz pain was observed in the EA group (p = 0.027; p < 0.001; p = 0.005, respectively) and in general pain in the AC group (p < 0.001). Decreased MTrP area in RTPz and LTPz were observed in AC (p < 0.001) and EA groups (RTPz, p = 0.003; LTPz, p = 0.005). Post-treatment SR in RTPz and LTPz was lower than pre-treatment in both treatment groups. 2D US and UE effectively characterized MTrP and surrounding tissue, pointing to the possibility of objective confirmation of subjective EA and AC treatment effects.

A critical evaluation of Quintner et al: missing the point

The objective of this article is to critically analyze a recent publication by Quinter, Bove and Cohen, published in Rheumatology, about myofascial pain syndrome and trigger points (Quintner et al., 2014). The authors concluded that the leading trigger point hypothesis is flawed in reasoning and in science. They claimed to have refuted the trigger point hypothesis. The current paper demonstrates that the Quintner et al. paper is a biased review of the literature replete with unsupported opinions and accusations. In summary, Quintner et al. have not presented any convincing evidence to believe that the Integrated TrP Hypothesis should be laid to rest.

Dry Needling Alters Trigger Points in the Upper Trapezius Muscle and Reduces Pain in Subjects With Chronic Myofascial Pain

OBJECTIVE

To determine whether dry needling of an active myofascial trigger point (MTrP) reduces pain and alters the status of the trigger point to either a non-spontaneously tender nodule or its resolution.

DESIGN

A prospective, nonrandomized, controlled, interventional clinical study.

SETTING

University campus.

PARTICIPANTS

A total of 56 subjects with neck or shoulder girdle pain of more than 3 months duration and active MTrPs were recruited from a campus-wide volunteer sample. Of these, 52 completed the study (23 male and 33 female). Their mean age was 35.8 years.

INTERVENTIONS

Three weekly dry needling treatments of a single active MTrP.

MAIN OUTCOME MEASURES

PRIMARY OUTCOMES

Baseline and posttreatment evaluations of pain using a verbal analogue scale, the Brief Pain Inventory, and the status of the MTrP as determined by digital palpation. Trigger points were rated as active (spontaneously painful), latent (requiring palpation to reproduce the characteristic pain), or resolved (no palpable nodule).

SECONDARY OUTCOMES

Profile of Mood States, Oswestry Disability Index, and Short Form 36 scores, and cervical range of motion.

RESULTS

PRIMARY OUTCOMES

A total of 41 subjects had a change in trigger point status from active to latent or resolved, and 11 subjects had no change (P < .001). Reduction in all pain scores was significant (P < .001).

SECONDARY OUTCOMES

Significant improvement in posttreatment cervical rotational asymmetry in subjects as follows: unilateral/bilateral MTrPs (P = .001 and P = 21, respectively); in pain pressure threshold in subjects with unilateral/bilateral MTrPs, (P = .006 and P = .012, respectively); improvement in the SF-36 mental health and physical functioning subscale scores (P = .019 and P = .03), respectively; and a decrease in the Oswestry Disability Index score (P = .003).

CONCLUSIONS

Dry needling reduces pain and changes MTrP status. Change in trigger point status is associated with a statistically and clinically significant reduction in pain. Reduction of pain is associated with improved mood, function, and level of disability.

Pain intensity and cervical range of motion in women with myofascial pain treated with acupuncture and electroacupuncture: a double-blinded, randomized clinical trial

BACKGROUND

Acupuncture stimulates points on the body, influencing the perception of myofascial pain or altering physiologic functions.

OBJECTIVE

The aim was to evaluate the effect of electroacupuncture (EAC) and acupuncture (AC) for myofascial pain of the upper trapezius and cervical range of motion, using SHAM acupuncture as control.

METHOD

Sixty women presenting at least one trigger point at the upper trapezius and local or referred pain for more than six months were randomized into EAC, AC, and SHAM groups. Eight sessions were scheduled and a follow-up was conducted after 28 days. The Visual Analog Scale assessed the intensity of local and general pain. A fleximeter assessed cervical movements. Data were analyzed using paired t or Wilcoxon's tests, ANOVA or Friedman or Kruskal-Wallis tests and Pearson's correlation (α=0.05).

RESULTS

There was reduction in general pain in the EAC and AC groups after eight sessions (P<0.001). A significant decrease in pain intensity occurred for the right trapezius in all groups and for the left trapezius in the EAC and AC groups. Intergroup comparisons showed improvement in general pain in the EAC and AC groups and in local pain intensity in the EAC group (P<0.05), which showed an increase in left rotation (P=0.049). The AC group showed increases in inclination (P=0.005) sustained until follow-up and rotation to the right (P=0.032).

CONCLUSION

EAC and AC were effective in reducing the pain intensity compared with SHAM. EAC was better than AC for local pain relief. These treatments can assist in increasing cervical range of motion, albeit subtly.

An update on botulinum toxin A injections of trigger points for myofascial pain

Myofascial pain syndrome (MPS) is a common chronic pain condition that is characterized by distinct "trigger points." Despite current treatments with physical therapy, analgesics, anti-depressants and trigger-point injections, myofascial pain remains a challenging chronic pain condition in clinical practice. Botulinum toxin A (BTX-A) can cause prolonged muscle relaxation through inhibition of acetylcholine release. It may offer some advantages over the current treatments for MPS by providing a longer sustained period of pain relief. Despite numerous clinical trials, the efficacy of BTX-A in alleviating MPS is not well-established due to mixed results from recent clinical trials. Active trigger points are associated with referred pain and greatly impact many aspects of activities of daily living, mood, and health status. This review is designed to analyze the clinical trials regarding the efficacy of BTX-A injection of active trigger points as a treatment for MPS. The literature referenced was obtained via a computer search with Google Scholar, Pubmed, Medline and EMbase. Our search terms included "Botulinum toxin," "myofascial pain," "trigger points," "myofascial trigger points," "chronic pain." Additional references were retrieved from the reference list of the reports found via this search. Studies were considered eligible for inclusion if they were double-blinded, randomized, controlled trials evaluating the efficacy of BTX-A injections into trigger points for pain reduction, and if the trigger point selection in the trial included referred pain and/or local twitch response. Open-label studies, case reports, and other non-randomized studies were excluded. Eight trials were found according to the above criteria and are summarized in Table 1. There are well-designed clinical trials to support the efficacy of trigger-point injections with BTX-A for MPS. However, further clinical trials with considerations of minimizing placebo effect, repeated dosing, adequate coverage of trigger points, and using ultrasound confirmation and guidance are required to provide conclusive evidence for BTX-A in the treatment of myofascial pain.

Mechanisms of Myofascial Pain

Myofascial pain syndrome is an important health problem. It affects a majority of the general population, impairs mobility, causes pain, and reduces the overall sense of well-being. Underlying this syndrome is the existence of painful taut bands of muscle that contain discrete, hypersensitive foci called myofascial trigger points. In spite of the significant impact on public health, a clear mechanistic understanding of the disorder does not exist. This is likely due to the complex nature of the disorder which involves the integration of cellular signaling, excitation-contraction coupling, neuromuscular inputs, local circulation, and energy metabolism. The difficulties are further exacerbated by the lack of an animal model for myofascial pain to test mechanistic hypothesis. In this review, current theories for myofascial pain are presented and their relative strengths and weaknesses are discussed. Based on new findings linking mechanoactivation of reactive oxygen species signaling to destabilized calcium signaling, we put forth a novel mechanistic hypothesis for the initiation and maintenance of myofascial trigger points. It is hoped that this lays a new foundation for understanding myofascial pain syndrome and how current therapies work, and gives key insights that will lead to the improvement of therapies for its treatment.