ABSTRACT
PURPOSE: This study explored the relationship between central sensitization symptoms, assessed using the Central Sensitization Inventory (CSI), and psychophysical factors in patients with chronic masticatory myofascial pain (MMP) transitioning from the acute to chronic stages. METHODS: In this study, 23 patients with MMP and 22 healthy volunteers were assessed using psychophysical tests, including measurements of pressure pain threshold (PPT) and temporal summation of pain (TSP). Additionally, CSI scores were recorded to evaluate central sensitization symptoms. RESULTS: Patients with chronic MMP showed significantly lower PPT in all masticatory muscles and extratrigeminal areas compared with controls. However, there was no significant correlation between CSI scores and psychophysical test results in patients with MMP. CONCLUSION: The significant enhancement of TSP in patients with subchronic MMP suggests a potential role in the onset of myofascial pain. The main finding suggests that sub-chronic symptom patients show higher CSI scores despite no sensory testing changes, indicating that central sensitization possibly precedes observable symptoms.
Subject(s)
Central Nervous System Sensitization , Pain Threshold , Humans , Female , Male , Adult , Central Nervous System Sensitization/physiology , Middle Aged , Case-Control Studies , Pain Measurement , Myofascial Pain Syndromes/physiopathology , Masticatory Muscles/physiopathology , Psychophysics , Young Adult , Temporomandibular Joint Dysfunction Syndrome/physiopathologyABSTRACT
BACKGROUND: Dysfunctional gliding of deep fascia and muscle layers forms the basis of myofascial pain and dysfunction, which can cause chronic shoulder pain. Ultrasound shear strain imaging may offer a non-invasive tool to quantitatively evaluate the extent of muscular dysfunctional gliding and its correlation with pain. This case study is the first to use ultrasound shear strain imaging to report the shear strain between the pectoralis major and minor muscles in shoulders with and without chronic pain. CASE PRESENTATION: The shear strain between the pectoralis major and minor muscles during shoulder rotation in a volunteer with chronic shoulder pain was measured with ultrasound shear strain imaging. The results show that the mean ± standard deviation shear strain was 0.40 ± 0.09 on the affected side, compared to 1.09 ± 0.18 on the unaffected side (p<0.05). The results suggest that myofascial dysfunction may cause the muscles to adhere together thereby reducing shear strain on the affected side. CONCLUSION: Our findings elucidate a potential pathophysiology of myofascial dysfunction in chronic shoulder pain and reveal the potential utility of ultrasound imaging to provide a useful biomarker for shear strain evaluation between the pectoralis major and minor muscles.
Subject(s)
Chronic Pain , Shoulder Pain , Ultrasonography , Humans , Shoulder Pain/diagnostic imaging , Shoulder Pain/physiopathology , Shoulder Pain/etiology , Chronic Pain/diagnostic imaging , Chronic Pain/physiopathology , Ultrasonography/methods , Myofascial Pain Syndromes/diagnostic imaging , Myofascial Pain Syndromes/physiopathology , Adult , Male , Pectoralis Muscles/diagnostic imaging , Pectoralis Muscles/physiopathology , Female , Shear StrengthABSTRACT
The objective of this study is to determine characteristics of patients with myofascial pain syndrome (MPS) of the low back and the degree to which the low back pain in the patients examined can be attributed to MPS. Twenty-five subjects with myofascial trigger point(s) [MTrP(s)] on the low back participated in this cross-sectional study. The location, number, and type of selected MTrPs were identified by palpation and verified by ultrasound. Pain pressure threshold, physical function, and other self-reported outcomes were measured. Significant differences were found in Group 1 (Active), 2 (Latent), 3 (Atypical, no twitching but with spontaneous pain), and 4 (Atypical, no twitching and no spontaneous pain) of participants in the number of MTrPs, current pain, and worst pain in the past 24 h (p = .001-.01). There were interaction effects between spontaneous pain and twitching response on reports of physical function, current pain, and worst pain (p = .002-.04). Participants in Group 3 reported lower levels of physical function, and higher levels of current pain and worst pain compared to those in Group 4. Participants in Group 1 and 2 had similar levels of physical function, current pain, and worst pain. The number of MTrPs is most closely associated with the level of pain. Spontaneous pain report seems to be a decisive factor associated with poor physical function; however, twitching response is not.
Subject(s)
Low Back Pain , Myofascial Pain Syndromes , Humans , Female , Male , Myofascial Pain Syndromes/physiopathology , Adult , Cross-Sectional Studies , Low Back Pain/physiopathology , Middle Aged , Trigger Points/physiopathology , Pain Measurement , Pain Threshold , UltrasonographyABSTRACT
INTRODUCTION: MPS is a chronic disorder caused by myofascial trigger points, leading to pain and limited neck movements due to impacted fascia. Studies have reported reduced fascia slides in chronic low back pain, but limited fascia slides in MPS patients are still unreported. AIM: We determined differences in upper trapezius' deep fascia slides between MPS and non-MPS participants. METHODS: Between January-August 2019, participants from diverse work sectors were recruited in Manila. An expert physiotherapist diagnosed MPS, while non-MPS participants performed full painless cervical movements. Participants underwent upper trapezius deep fascia scans on both shoulders while performing six cervical movements. An HS1 Konica Minolta ultrasound recorded the data. Two blinded physiotherapists used Tracker 5.0 © 2018 to analyze videos and quantify deep fascia slides by measuring the distance between two x-axis points. The Multivariate analysis of variance (MANOVA) assessed deep fascia slide differences in six active cervical movements. Pillai's Trace, with a range of 0-1 and a p-value of <0.05, was set. Effect sizes in individuals with and without MPS were calculated using Hedges' g and Cohen's d. RESULTS: Of the 327 participants (136 non-MPS, 191 MPS), 101 MPS participants had shoulder pain for <1 year and 103 experienced unilateral pain. The study examined 3800 ultrasound videos but found no significant difference in deep fascia slides across cervical movements between MPS and non-MPS groups (Pillai's Trace = 0.004, p = 0.94). Minor differences in deep fascia displacement were observed, with small effect sizes (g = 0.02-0.08). CONCLUSION: A limited deep fascia slide does not characterize MPS participants from non-MPS participants.
Subject(s)
Fascia , Myofascial Pain Syndromes , Superficial Back Muscles , Humans , Myofascial Pain Syndromes/physiopathology , Female , Adult , Superficial Back Muscles/physiopathology , Superficial Back Muscles/diagnostic imaging , Case-Control Studies , Male , Fascia/diagnostic imaging , Fascia/physiopathology , Middle Aged , Ultrasonography/methods , Young Adult , Trigger Points/physiopathologyABSTRACT
CONTEXT: Myofascial pain syndrome (MPS) is primarily characterized by myofascial trigger points related to fascial adhesions. MPS hinders fascial flexibility and mobility, leading to myofascial limitations, dysfunctional movement, and limitation of motion (LOM). OBJECTIVES: This study determined the association of age, sex, type of work, symptom chronicity, symptom laterality, cervical LOM, altered direction of fascial displacement, and magnitude of superficial fascial displacement during active cervical flexion with the clinical diagnosis of MPS. METHODS: A cross-sectional study selectively included MPS and non-MPS participants from different workplaces from January to October 2019. The MPS group exhibited clinical symptoms like tender spots, recognized pain patterns, and local twitch response upon palpation, often accompanied by cervical LOM. The non-MPS group lacked these symptoms, and those with certain pre-existing conditions or recent physiotherapy were not part of the study. Participants performed cervical active range of motion (AROM) while a sonographer recorded superficial fascial displacement utilizing ultrasound, which was later analyzed by three physiotherapists with the Tracker. Aiming for a multiple regression R-squared of 0.2, the target was 384 participants to account for a 20â¯% dropout, resulting in 307 participants after attrition. To explore the relationships between MPS and various factors, logistic regression models, rigorously tested for reliability and validity, were utilized. RESULTS: In the study, there were 192 participants with MPS and 137 without MPS. The median ages were 33 years for the non-MPS group and 38 years for the MPS group. The adjusted model found significant links for sex (odds ratio [OR]=2.63, p<0.01), symptom chronicity (OR=8.28, p<0.01), and cervical LOM (OR=3.77, p=0.01). However, age and the presence of nodules/taut bands were not statistically significant (p>0.05). Also, the type of work, the direction of fascial displacement, and the difference in superficial fascial displacement during cervical flexion did not show a significant association with the clinical diagnosis of MPS (p>0.05). The adjusted model had a sensitivity of 73.80â¯% and a specificity of 81.34â¯%, correctly identifying 84.66â¯% of positive cases and 68.99â¯% of negative ones, resulting in an overall accuracy of 76.95â¯% in predicting MPS. CONCLUSIONS: We provided an in-depth examination of MPS, identifying sex, duration of symptoms, and cervical LOM as significant predictive factors in its diagnosis. The study emphasizes the critical role of these variables in the accurate diagnosis of MPS, while delineating the comparatively minimal diagnostic value of other factors such as age, type of occupation, presence of nodules or taut bands, and variations in fascial displacement. This study underscores the imperative for further scholarly inquiry into the role of fascial involvement in musculoskeletal disorders, with the objective of enhancing both the theoretical understanding and diagnostic practices in this medical domain.
Subject(s)
Fascia , Myofascial Pain Syndromes , Range of Motion, Articular , Humans , Cross-Sectional Studies , Female , Myofascial Pain Syndromes/diagnosis , Myofascial Pain Syndromes/physiopathology , Male , Adult , Middle Aged , Range of Motion, Articular/physiology , Fascia/diagnostic imaging , Fascia/physiopathology , Cervical Vertebrae/physiopathology , Cervical Vertebrae/diagnostic imaging , Ultrasonography , Young Adult , Diagnosis, DifferentialABSTRACT
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.
Subject(s)
Elasticity Imaging Techniques , Feasibility Studies , Humans , Elasticity Imaging Techniques/methods , Male , Adult , Female , Magnetic Resonance Imaging/methods , Muscle, Skeletal/diagnostic imaging , Myofascial Pain Syndromes/diagnostic imaging , Myofascial Pain Syndromes/physiopathology , Thigh/diagnostic imaging , Young Adult , Healthy VolunteersABSTRACT
BACKGROUND: Myofascial Trigger Points (MTrPs) play a significant role in the pathogenesis of Tension Type Headache (TTH). Abnormal cranio-cervical posture has been linked to various types of headaches. However, the correlation between MTrPs sensitivity, cervical postural alignment, and clinical measures of headache has not been extensively studied in patients with TTH. OBJECTIVES: To investigate the relationship between MTrPs sensitivity in cervical and pericranial muscles, cervical postural abnormality, and clinical headache parameters in patients with TTH. Furthermore, to investigate the effect of sex on the examined variables and their association with headache type (episodic vs chronic TTH). METHODS: A total of 72 patients with TTH of both sexes were enrolled in this study. Headache frequency and disability as clinical measures of headache, pressure pain threshold (PPT) of bilateral upper trapezius (UT) and suboccipital (SUB) muscles, cervical lordosis angle (CA), and anterior head translation (AHT) were measured. RESULTS: Pericranial MTrPs sensitivity did not demonstrate any correlation with clinical headache parameters or cervical postural abnormality. However, there was a significant correlation between the frequency of headaches and the level of disability (r = 0.32, P < 0.05). In addition, episodic TTH was more prevalent in females who exhibited greater AHT and MTrPs sensitivity of both bilateral UT and right SUB muscles than males. CONCLUSIONS: There was no correlation found between the frequency of headaches and the level of disability with measures of cervical posture alignment or MTrPs sensitivity in individuals with TTH.. Based on findings, Clinicians should consider sex differences when assessing patients with TTH.
Subject(s)
Myofascial Pain Syndromes , Pain Threshold , Posture , Tension-Type Headache , Trigger Points , Humans , Female , Male , Tension-Type Headache/physiopathology , Adult , Trigger Points/physiopathology , Myofascial Pain Syndromes/physiopathology , Posture/physiology , Middle Aged , Pain Threshold/physiology , Neck Muscles/physiopathology , Sex Factors , Pain Measurement , Cervical Vertebrae/physiopathology , Young AdultABSTRACT
There are studies that show the better balance after dry needling in lumbar pain. However, the postural control effects after foot dry needling are unknown. Our objective was to check if dry needling reduces postural control. Eighteen subjects with flexor digitorum brevis (FDB) muscle Myofascial trigger point were evaluated pre- and post-deep dry needling. We measured stabilometric variables in a pre-post study. We have found significant differences in three stabilometric variables: surface with eyes closed (29.36-53.21 mm2 ) (p = 0.000), medium speed of the laterolateral displacement with eyes closed (1.42-1.64 mm/s) (p = 0.004), and medium speed of the anteroposterior displacement with eyes closed (1.30-1.53 mm/s) (p = 0.025). Dry needling therapy application in FDB muscle reduces standing postural control with eyes closed.
Subject(s)
Dry Needling , Myofascial Pain Syndromes , Postural Balance , Trigger Points , Dry Needling/adverse effects , Muscle, Skeletal , Standing Position , Humans , Myofascial Pain Syndromes/physiopathology , Myofascial Pain Syndromes/therapy , Male , Female , FootABSTRACT
OBJECTIVE: The objective of this study was to measure the intra- and inter-rater reliability of the quantitative sensory testing for measuring the thermal pain threshold on myofascial trigger points in the upper trapezius muscle of individuals with chronic neck pain. METHODS: Thirty female participants were included, aged between 18 and 45 years and with bilateral myofascial trigger points, active and centrally located in the upper trapezius muscle. Two measurements with quantitative sensory testing were performed by each examiner at an interval of 1 week between them. RESULTS: We observed substantial reliability for the intra-rater analysis (intraclass correlation coefficient ranging between 0.876 and 0.896) and excellent reliability for the inter-rater analysis (intraclass correlation coefficient ranging between 0.917 and 0.954). CONCLUSION: The measurement of the thermal pain threshold on myofascial trigger points in individuals with chronic neck pain has acceptable reliability values, supporting the use of the quantitative sensory testing in the research setting and the clinical environment.
Subject(s)
Myofascial Pain Syndromes , Neck Pain , Superficial Back Muscles , Trigger Points , Adolescent , Adult , Chronic Pain , Female , Humans , Middle Aged , Myofascial Pain Syndromes/diagnosis , Myofascial Pain Syndromes/physiopathology , Neck Pain/epidemiology , Reproducibility of Results , Superficial Back Muscles/physiopathology , Trigger Points/physiopathology , Young AdultABSTRACT
SUMMARY OBJECTIVE: The objective of this study was to measure the intra- and inter-rater reliability of the quantitative sensory testing for measuring the thermal pain threshold on myofascial trigger points in the upper trapezius muscle of individuals with chronic neck pain. METHODS: Thirty female participants were included, aged between 18 and 45 years and with bilateral myofascial trigger points, active and centrally located in the upper trapezius muscle. Two measurements with quantitative sensory testing were performed by each examiner at an interval of 1 week between them. RESULTS: We observed substantial reliability for the intra-rater analysis (intraclass correlation coefficient ranging between 0.876 and 0.896) and excellent reliability for the inter-rater analysis (intraclass correlation coefficient ranging between 0.917 and 0.954). CONCLUSION: The measurement of the thermal pain threshold on myofascial trigger points in individuals with chronic neck pain has acceptable reliability values, supporting the use of the quantitative sensory testing in the research setting and the clinical environment.
Subject(s)
Humans , Female , Adolescent , Adult , Young Adult , Neck Pain/epidemiology , Trigger Points/physiopathology , Superficial Back Muscles/physiopathology , Myofascial Pain Syndromes/diagnosis , Myofascial Pain Syndromes/physiopathology , Reproducibility of Results , Chronic Pain , Middle AgedABSTRACT
OBJECTIVE: Dry needling is a commonly used treatment technique for myofascial pain syndromes, such as trapezius myalgia. Despite the shown positive clinical effects on pain, the underlying mechanisms of action, such as the effect on muscle electrophysiology, remain unclear. The aim of this study was to investigate the effect of dry needling, compared with sham needling, in the upper trapezius muscle on surface electromyography activity and the relation with pain in office workers with trapezius myalgia. DESIGN: For this experimental randomized controlled trial, 43 office workers with work-related trapezius myalgia were included. Surface electromyography activity was measured before and after a pain-provoking computer task and immediately after, 15, and 30 mins after treatment with dry or sham needling. Pain scores were evaluated at the same time points as well as 1, 2, and 7 days after treatment. RESULTS: No significant differences in surface electromyography activity between dry needling and sham needling were found. Significant positive low to moderate Spearman correlations were found between surface electromyography activity and pain levels after dry needling treatment. CONCLUSIONS: This study shows no immediate effects of dry needling on the electrophysiology of the upper trapezius muscle, compared with sham needling.
Subject(s)
Dry Needling , Electromyography/methods , Myalgia/rehabilitation , Myofascial Pain Syndromes/physiopathology , Occupational Diseases/rehabilitation , Adult , Female , Humans , Male , Middle Aged , Myalgia/physiopathology , Myofascial Pain Syndromes/rehabilitation , Occupational Diseases/physiopathology , Statistics, Nonparametric , Superficial Back Muscles/physiopathology , Treatment OutcomeABSTRACT
Masticatory myofascial pain (MMP) is one of the most common causes of chronic orofacial pain in patients with temporomandibular disorders. To explore the antinociceptive effects of ultra-low frequency transcutaneous electrical nerve stimulation (ULF-TENS) on alterations of pain-related biochemicals, electrophysiology and jaw-opening movement in an animal model with MMP, a total of 40 rats were randomly and equally assigned to four groups; i.e., animals with MMP receiving either ULF-TENS or sham treatment, as well as those with sham-MMP receiving either ULF-TENS or sham treatment. MMP was induced by electrically stimulated repetitive tetanic contraction of masticatory muscle for 14 days. ULF-TENS was then performed at myofascial trigger points of masticatory muscles for seven days. Measurable outcomes included maximum jaw-opening distance, prevalence of endplate noise (EPN), and immunohistochemistry for substance P (SP) and µ-opiate receptors (MOR) in parabrachial nucleus and c-Fos in rostral ventromedial medulla. There were significant improvements in maximum jaw-opening distance and EPN prevalence after ULF-TENS in animals with MMP. ULF-TENS also significantly reduced SP overexpression, increased MOR expression in parabrachial nucleus, and increased c-Fos expression in rostral ventromedial medulla. ULF-TENS may represent a novel and applicable therapeutic approach for improvement of orofacial pain induced by MMP.
Subject(s)
Chronic Pain/complications , Chronic Pain/therapy , Temporomandibular Joint Disorders/complications , Temporomandibular Joint Disorders/physiopathology , Transcutaneous Electric Nerve Stimulation , Animals , Chronic Pain/physiopathology , Disease Models, Animal , Electromyography , Electrophysiological Phenomena , Masticatory Muscles/physiopathology , Motor Endplate/physiopathology , Myofascial Pain Syndromes/complications , Myofascial Pain Syndromes/physiopathology , Myofascial Pain Syndromes/therapy , Parabrachial Nucleus/metabolism , Proto-Oncogene Proteins c-fos/metabolism , Rats , Receptors, Opioid, mu/metabolism , Substance P/metabolismABSTRACT
ABSTRACT: This study systematically reviewed the published literature on the objective characterization of myofascial pain syndrome and myofascial trigger points using imaging methods. PubMed, Embase, Ovid, and the Cochrane Library databases were used, whereas citation searching was conducted in Scopus. Citations were restricted to those published in English and in peer-reviewed journals between 2000 and 2021. Of 1762 abstracts screened, 69 articles underwent full-text review, and 33 were included. Imaging data assessing myofascial trigger points or myofascial pain syndrome were extracted, and important qualitative and quantitative information on general study methodologies, study populations, sample sizes, and myofascial trigger point/myofascial pain syndrome evaluation were tabulated. Methodological quality of eligible studies was assessed based on the Quality Assessment of Diagnostic Accuracy Studies criteria. Biomechanical properties and blood flow of active and latent myofascial trigger points assessed via imaging were found to be quantifiably distinct from those of healthy tissue. Although these studies show promise, more studies are needed. Future studies should focus on assessing diagnostic test accuracy and testing the reproducibility of results to establish the best performing methods. Increasing methodological consistency would further motivate implementing imaging methods in larger clinical studies. Considering the evidence on efficacy, cost, ease of use and time constraints, ultrasound-based methods are currently the imaging modalities of choice for myofascial pain syndrome/myofascial trigger point assessment.
Subject(s)
Myofascial Pain Syndromes/diagnostic imaging , Myofascial Pain Syndromes/physiopathology , Trigger Points/diagnostic imaging , Trigger Points/physiopathology , Humans , Magnetic Resonance Imaging , Thermography , UltrasonographyABSTRACT
BACKGROUND: Although studies examined kinesiological taping (KT) and extracorporeal shock wave therapy (ESWT) in myofascial pain syndrome (MPS), no study has yet compared these two treatments. OBJECTIVE: This study aimed to compare the efficacy of KT and ESWT on pain, pain threshold, functional level and neck movements in the treatment of MPS, which is an important cause of disability and constitutes 50-80% of chronic painful diseases. METHODS: Two hundred and sixty-two patients diagnosed with MPS in the upper part of the unilateral trapeze muscle were included in the study. The patients were divided into three groups according to the treatment they received: Group 1 (n= 75): ESWT + exercise, Group 2 (n= 82): KT + exercise, Group 3 (n= 105) and the latter receiving only exercise therapy (control group). Visual analog scale (VAS), pain threshold with algometer, Neck Disability Index (NDI), and neck contralateral lateral flexion angle were assessed before and three months after treatment. RESULTS: VAS, pain threshold, NDI and contralateral flexion angle values after treatment improved significantly in the ESWT and KT groups (p< 0.05) compared to the control group. The level of improvement in the ESWT group was higher (p< 0.05) than in the KT group in terms of VAS, pain threshold and NDI scores. CONCLUSION: Exercise, KT and ESWT applications in MPS were effective in all of the parameters examined. However, the ESWT + exercise therapy was more effective in terms of pain, pain threshold and disability.
Subject(s)
Athletic Tape , Exercise Therapy , Extracorporeal Shockwave Therapy , Myofascial Pain Syndromes/therapy , Adult , Aged , Combined Modality Therapy , Female , Humans , Male , Middle Aged , Myofascial Pain Syndromes/physiopathology , Pain Measurement , Pain Threshold/physiology , Range of Motion, Articular/physiology , Superficial Back Muscles/physiopathology , Treatment Outcome , Young AdultABSTRACT
BACKGROUND: Neck pain is frequent in patients with migraine. Likewise, evidence for inflammatory processes in the trapezius muscles is accumulating. However, non-invasive and objectively assessable correlates are missing in vivo. METHODS: Twenty-one subjects with episodic migraine (mean age: 24.6 ± 3.1 years, 18 females) and 22 controls (mean age: 23.0 ± 2.2 years, 17 females) without any history of headache prospectively underwent physical examination and quantitative magnetic resonance imaging of the trapezius muscles. A T2-prepared turbo spin-echo sequence was acquired for manual segmentation of the trapezius muscles and extraction of mean T2 values. RESULTS: There were no statistically significant differences regarding age, sex, body mass index, or number of myofascial trigger points (mTrPs) between groups. All patients with migraine presented with mTrPs in the trapezius muscles. T2 of the entire trapezius muscles was significantly higher in the migraine group when compared to controls (31.1 ± 0.8 ms vs. 30.1 ± 1.1 ms; p = 0.002). CONCLUSIONS: Elevated T2 values of the trapezius muscles may indicate subtle inflammatory processes within musculature among patients with migraine because T2 increase is likely to stem from edematous changes. Future work may validate this finding in larger cohorts, but muscle T2 might have potential to develop into a viable in vivo biomarker for muscular affection in migraine.
Subject(s)
Magnetic Resonance Imaging/methods , Myofascial Pain Syndromes/physiopathology , Neck Pain/physiopathology , Superficial Back Muscles/diagnostic imaging , Superficial Back Muscles/physiopathology , Trigger Points/physiopathology , Adult , Case-Control Studies , Female , Humans , Migraine Disorders/diagnostic imaging , Neck Muscles/diagnostic imaging , Neck Pain/etiology , Prospective Studies , Young AdultABSTRACT
The purpose of this study was to investigate whether the ERK signaling pathway was involved in ameliorating chronic myofascial hyperalgesia from contused gastrocnemius muscle in rats. We established an animal model associated with myofascial pain syndrome and described the mechanism of muscle pain in an animal model. Changes in the mechanical pain threshold were observed 0.5, 1, 2, 3, 4, 5, 8, 12, 18, and 24 h after ERK inhibitor injection around myofascial trigger points (MTrPs) of the gastrocnemius muscle in rats. Morphological changes in gastrocnemius muscle cells were observed by hematoxylin and eosin (H&E) staining. ERK signaling pathway activation was detected through immunohistochemistry and Western blotting. The main morphological characteristics of injured muscle fibers around MTrPs include gathered circular or elliptical shapes of different sizes in the cross-section and continuous inflated and tapering fibers in the longitudinal section. After intramuscular injection of U0126 (ERK inhibitor), the mechanical pain threshold significantly increased. The reduction in mechanical hyperalgesia was accompanied by reduced ERK protein phosphorylation, myosin light chain kinase (MLCK) protein, p-MLC protein expression, and the cross-sectional area of skeletal muscle cells around MTrPs. An ERK inhibitor contributed to the attenuation of mechanical hyperalgesia in the rat myofascial pain model, and the increase in pain threshold may be related to MLCK downregulation and other related contraction-associated proteins by ERK.
Subject(s)
MAP Kinase Signaling System , Myalgia/enzymology , Trigger Points/pathology , Animals , Hyperalgesia/complications , MAP Kinase Signaling System/drug effects , Male , Muscle Cells/drug effects , Muscle Cells/pathology , Muscle, Skeletal/drug effects , Muscle, Skeletal/pathology , Myalgia/complications , Myalgia/pathology , Myalgia/physiopathology , Myofascial Pain Syndromes/complications , Myofascial Pain Syndromes/pathology , Myofascial Pain Syndromes/physiopathology , Myosin-Light-Chain Kinase/metabolism , Pain Threshold/drug effects , Phosphorylation/drug effects , Protein Kinase Inhibitors/pharmacology , Rats, Sprague-DawleyABSTRACT
Western societies are facing a clear increase in the rate of obesity and overweight which are responsible for musculoskeletal pain. Some of the substances described in the environment of myofascial trigger points (MTrPs) are the same as those found in the skeletal muscle of obese people, such as cytokines. Furthermore, elevated neuromuscular neurotransmission has been associated with MTrPs. The main objective of this study is to assess whether obesity or overweight may be a facilitator of myofascial pain. The experiments were performed on male Swiss mice. One experimental group was given a typical "cafeteria" diet and another group a commercial high-fat diet for six weeks. Intramuscular adipocytes were assessed with Sudan III. The functional study was performed with electromyographic recording to determine the plaque noise and intracellular recording of miniature endplate potentials (MEPPs). The intake of a cafeteria diet showed the presence of more adipocytes in muscle tissue, but not with the fat-supplemented diet. Both experimental groups showed an increase in the plaque noise and an increase in the frequency of MEPPs that lasted several weeks after interrupting diets. In summary, the supply of a hypercaloric diet for six weeks in mice increases spontaneous neurotransmission, thus facilitating the development of MTrPs.
Subject(s)
Acetylcholine/metabolism , Diet, High-Fat , Neuromuscular Junction/metabolism , Overweight/physiopathology , Synaptic Transmission , Adipocytes/cytology , Animals , Dietary Fats/administration & dosage , Electromyography , Mice , Miniature Postsynaptic Potentials , Muscle, Skeletal/cytology , Myofascial Pain Syndromes/physiopathology , Obesity/physiopathology , Weight GainABSTRACT
Myofascial Pain Syndrome (MPS) is a regional pain disorder that affects every age-group and is characterized by the presence of trigger points (TrPs) within muscles or fascia. MPS is typically diagnosed via physical exam, and the general agreement for diagnostic criteria includes the presence of TrPs, pain upon palpation, a referred pain pattern, and a local twitch response. The prevalence of MPS among patients presenting to medical clinics due to pain ranges anywhere from 30 to 93%. This may be due to the lack of clear criteria and guidelines in diagnosing MPS. Despite the prevalence of MPS, its pathophysiology remains incompletely understood. There are many different ways to manage and treat MPS. Some include exercise, TrP injections, medications, and other alternative therapies. More research is needed to form uniformly-accepted diagnostic criteria and treatments.
Subject(s)
Analgesics/administration & dosage , Anesthetics, Local/administration & dosage , Myofascial Pain Syndromes/physiopathology , Myofascial Pain Syndromes/therapy , Pain Management/methods , Trigger Points , Exercise Therapy/methods , Humans , Myofascial Pain Syndromes/diagnosis , Transcutaneous Electric Nerve Stimulation/methods , Treatment Outcome , Trigger Points/physiopathologyABSTRACT
OBJECTIVE: The purpose of this study was to assess the effects of 4-week protocol of diacutaneous fibrolysis (DF) compared with simulated DF (sham-DF) on myalgia and mouth opening. METHODS: In a sham randomized controlled trial, 34 women with temporomandibular disorders and myofascial pain were randomly divided as intervention group (IG) and sham-DF group (SG). The IG received 4 weeks of real DF, and the SG received sham. Pain was assessed through the visual analog scale and pressure pain thresholds (PPTs) on the temporomandibular joint (TMJ), and over the temporal and masseter muscles. The Mandibular Function Impairment Questionnaire was used to classify the participants regarding to the severity of the functional limitation related to TMD. RESULTS: Pain scores decreased for both groups, but the IG showed lower values at week 4, with between-group differences. Bilateral temporal PPT showed higher values at week 4, with between-group differences. The SG had lower PPTs but the IG had higher PPTs, both compared to baseline results. The time-by-group interaction and the frequency of participants above 40 mm of mouth opening showed a significant difference for the IG over time with higher results at the 4-week assessment compared to its own baseline. Both groups showed lower MFIQ scores from baseline to 4-week assessment. There was a lower frequency of a moderate level of severity for the IG. No differences were observed for TMJ or for the masseter muscles PPT. CONCLUSION: Improvements were observed for visual analog scale scores and PPTs on temporal muscles. There was a group-by-time interaction in the IG, suggesting a possible potential use of DF for mouth opening.
Subject(s)
Facial Pain/therapy , Masticatory Muscles/physiopathology , Myalgia/therapy , Myofascial Pain Syndromes/therapy , Physical Therapy Modalities , Temporomandibular Joint Disorders/therapy , Temporomandibular Joint/physiopathology , Adult , Facial Pain/pathology , Facial Pain/physiopathology , Female , Humans , Mandible/pathology , Mandible/physiopathology , Massage , Masseter Muscle/pathology , Masseter Muscle/physiopathology , Masticatory Muscles/pathology , Mouth , Myalgia/physiopathology , Myofascial Pain Syndromes/physiopathology , Pain Measurement , Pain Threshold , Severity of Illness Index , Temporal Muscle/pathology , Temporal Muscle/physiopathology , Temporomandibular Joint/pathology , Temporomandibular Joint Disorders/pathology , Temporomandibular Joint Disorders/physiopathology , Treatment Outcome , Young AdultABSTRACT
PURPOSE OF REVIEW: Myofascial pain syndrome (MPS) is a musculoskeletal pain condition that stems from localized, taut regions of skeletal muscle and fascia, termed trigger points. The purpose of this comprehensive review is to provide updated information on prevalence, pathophysiology, and treatment modalities with a focus on interventional modalities in managing MPS. RECENT FINDINGS: Though MPS can present acutely, it frequently presents as a chronic condition, affecting up to 85% of adults during their lifetime. MPS is an often-overlooked component of pain with overarching effects on society, including patient quality of life, physical and social functioning, emotional well-being, energy, and costs on health care. The prevalence of MPS is generally increased among patients with other chronic pain disorders and has been associated with various other conditions such as bladder pain syndrome, endometriosis, and anxiety. MPS is poorly understood and remains a challenging condition to treat. Non-pharmacologic treatment modalities such as acupuncture, massage, transcutaneous electrical stimulation, and interferential current therapy may offer relief to some patients with MPS. Additional studies are warranted to get a better understanding of managing myofascial pain.