Platelet-derived Growth Factor Receptor-α Induces Contraction Knots and Inflammatory Pain-like Behavior in a Rat Model of Myofascial Trigger Points.

BACKGROUND: Myofascial trigger points (MTrPs) are the primary etiological characteristics of chronic myofascial pain syndrome. Receptor tyrosine kinases (RTKs) are associated with signal transduction in the central mechanisms of chronic pain, but the role of RTKs in the peripheral mechanisms of MTrPs remains unclear. The current study aimed to identify RTKs expression in MTrPs and elucidate the molecular mechanisms through which platelet-derived growth factor receptor-α (PDGFR-α) induces contraction knots and inflammatory pain-like behavior in a rat model of myofascial trigger points. METHODS: MTrPs tissue samples were obtained from the trapezius muscles of patients with myofascial pain syndrome through needle biopsy, and PDGFR-α activation was analyzed by microarray, enzyme-linked immunosorbent assay, and histological staining. Sprague-Dawley rats (male and female) were used to investigate PDGFR-α signaling, assessing pain-like behaviors with Randall-Selitto and nest-building tests. Muscle fiber and sarcomere morphologies were observed using histology and electron microscopy. The PDGFR-α binding protein was identified by coimmunoprecipitation, liquid chromatograph mass spectrometer, and molecular docking. PDGFR-α-related protein or gene levels, muscle contraction, and inflammatory markers were determined by Western blot and reverse-transcription quantitative polymerase chain reaction. RESULTS: PDGFR-α phosphorylation levels were elevated in the MTrPs tissues of individuals with trapezius muscle pain and were positively correlated with pain intensity. In rats, PDGFR-α activation caused pain-like behaviors and muscle contraction via the Janus kinase 2/signal transducer and activator of transcription-3 (JAK2/STAT3) pathway. JAK2/STAT3 inhibitors reversed the pain-like behaviors and muscle contraction induced by PDGFR-α activation. Collagen type I α 1 (COL1A1) binds to PDGFR-α and promotes its phosphorylation, which contributed to pain-like behaviors and muscle contraction. CONCLUSIONS: COL1A1-induced phosphorylation of PDGFR-α and the subsequent activation of the JAK2/STAT3 pathway may induce dysfunctional muscle contraction and increased nociception at MTrPs.

Reliability of quantitative sensory testing on myofascial trigger points in the upper trapezius muscle of individuals with chronic neck pain

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.

Ultra-Low Frequency Transcutaneous Electrical Nerve Stimulation on Pain Modulation in a Rat Model with Myogenous Temporomandibular Dysfunction.

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.

Interventions for myofascial pain syndrome in cancer pain: recent advances: why, when, where and how.

PURPOSE OF REVIEW: Pain is one of the most feared and most common symptoms of cancer, experienced by 38-85% of patients. Pain in terminally ill cancer patients is a multidimensional experience caused by a diverse array of factors - cancer itself, its treatment or other causes. Studies have shown a high incidence of myofascial pain syndrome (MPS) in patients with cancer and the knowledge of myofascial trigger points (MTrPs) is important to address and manage existing pain, and to prevent the recurrence of pain. This review aims to summarize recent advances in interventions for managing MPS in patients with cancer. RECENT FINDINGS: Database searches were conducted on MEDLINE, CINAHL, and Google Scholar to locate all studies published from inception until April 2019 using the keywords cancer pain, myofascial pain, TrPs with emphasis of any methodological quality that included interventions for MPS. MPS in advanced cancer patients are more commonly observed along with other cancer pains rather than independently with a prevalence of 11.9-48% in those patients diagnosed with cancer of head and neck and breast cancer. SUMMARY: Interventional therapies employing ultrasound guided injection of the MTrPs is gaining popularity in the management of MPS in cancer pain and may be a better alternative than the use of opioid analgesics in the multidisciplinary management.

Myofascial component of cancer pain review.

BACKGROUND: Pain is a common complaint of cancer patients, experienced by 38%-85% of patients. Some studies have shown a high incidence of myofascial pain syndrome (MPS) in cancer patients. AIMS: 1) To estimate the prevalence of MPS in cancer patients; 2) to examine the efficacy of current treatment options for MPS in cancer patients. METHODS: Narrative review. PubMed, CINAHL, PEDro, and Google Scholar databases were searched from inception until November 2017, for the keywords: cancer; cancer pain; breast cancer; mastectomy; lumpectomy; myofascial pain; trigger points. Trials of any methodological quality were included. All published material with an emphasis on randomized control trials was analyzed. RESULTS: MPS is prevalent in cancer patients who suffer from pain, with a prevalence of between 11.9% and 44.8% in those diagnosed either with neck or head or breast cancer. Clinical studies showed conflicting results. Four interventional studies found that specific treatment for MPS may reduce the prevalence of active myofascial trigger points and therefore decrease pain level, sensitivity, and improve range of motion (in shoulder) in cancer patients. Two recent randomized control trials showed that pressure release of trigger points provides no additional beneficial effects to a standard physical therapy program for upper limb pain and function after breast cancer surgery. CONCLUSIONS: We recommend including the evaluation of myofascial pain in routine clinical examination of cancer patients suffering from pain. Future studies are needed to investigate the long- and short-term effect of MPS treatments in cancer patients.

Autonomic neurophysiologic implications of disorders comorbid with bladder pain syndrome vs myofascial pelvic pain.

AIMS: The neuropathophysiology of a debilitating chronic urologic pain condition, bladder pain syndrome (BPS), remains unknown. Our recent data suggests withdrawal of cardiovagal modulation in subjects with BPS, in contrast to sympathetic nervous system dysfunction in another chronic pelvic pain syndrome, myofascial pelvic pain (MPP). We evaluated whether comorbid disorders differentially associated with BPS vs MPP shed additional light on these autonomic differences. METHODS: We compared the presence and relative time of onset of 27 other medical conditions in women with BPS, MPP, both syndromes, and healthy subjects. Analysis included an adjustment for multiple comparisons. RESULTS: Among 107 female subjects (BPS alone = 32; BPS with MPP = 36; MPP alone = 9; healthy controls = 30), comorbidities differentially associated with BPS included irritable bowel syndrome (IBS), dyspepsia, and chronic nausea, whereas those associated with MPP included migraine headache and dyspepsia, consistent with the distinct autonomic neurophysiologic signatures of the two disorders. PTSD (earliest), anxiety, depression, migraine headache, fibromyalgia, chronic fatigue, and IBS usually preceded BPS or MPP. PTSD and the presence of both pelvic pain disorders in the same subject correlated with significantly increased comorbid burden. CONCLUSIONS: Our study suggests a distinct pattern of comorbid conditions in women with BPS. These findings further support our hypothesis of primary vagal defect in BPS as compared with primary sympathetic defect in MPP, suggesting a new model for chronic these pelvic pain syndromes. Chronologically, PTSD, migraine, dysmenorrhea, and IBS occurred early, supporting a role for PTSD or its trigger in the pathophysiology of chronic pelvic pain.

Comparison of Voiding Dysfunction Phenotypes in Women with Interstitial Cystitis/Bladder Pain and Myofascial Pelvic Pain: Results from the ICEPAC Trial.

OBJECTIVE: To evaluate whether voiding parameters differ in patients with the common overlapping pelvic pain disorders, interstitial cystitis/bladder pain syndrome (IC/BPS), and myofascial pelvic pain (MPP). METHODS: Uroflow and voiding diary assessed voiding phenotypes in this prospective cohort study (ICEPAC) of women comparing IC/BPS, IC/BPS +MPP, MPP, and healthy control (HC) subjects. RESULTS: In 36 HC, 24 IC/BPS, 37 IC/BPS + MPP, and 14 MPP subjects, the voiding diary measurements indicate lower voided volumes in IC/BPS and IC/BPS + MPP groups (185 ± 24 mL, 169 ± 20 mL, respectively) compared to HC and MPP groups (294 ± 24 mL, 226 ± 36 mL, respectively; P <.05, P <.05), as well as higher 24-hour voiding frequency (11.6 ± 0.8 and 11 ± 1.2 voids/24 hours, respectively; HC 7.1 ± 0.5 voids/24 hours; P <.05, P <.05; MPP group 9 ± 1.2 voids/24 hours; P <.05, P <.05). Uroflow showed higher HC average flow rate (12.87 ± 0.92) compared to IC/BPS, IC/BPS+MPP, and MPP (8.31 ± 1.20, 8.02 ± 0.80, 8.17 ± 1.38, respectively; P <.01, P <.01, P <.05) and peak flow rate (27.0 ± 1.83) and IC/BPS, IC/BPS+MPP and MPP (16.20 ± 2.2, 17.33 ± 1.64, 17.21 ± 2.69 respectively; P <.01, P <.01, P <.05). CONCLUSION: This quantitative evaluation of voiding diary and uroflow metrics reveals distinct voiding phenotypes, which can aid in the diagnosis of chronic pelvic pain syndromes. Patients with IC/BPS had more pain with a full bladder despite similar overall pain scores. Peak and average flow rates do not provide any differentiating power between IC/BPS and MPP patients. A longer time to peak flow may favor MPP though this finding needs confirmation.

Myofascial trigger points in migraine and tension-type headache.

BACKGROUND: A myofascial trigger point is defined as a hyperirritable spot in skeletal muscle that is associated with a hypersensitive palpable nodule in a taut band. It has been suggested that myofascial trigger points take part in chronic pain conditions including primary headache disorders. The aim of this narrative review is to present an overview of the current imaging modalities used for the detection of myofascial trigger points and to review studies of myofascial trigger points in migraine and tension-type headache. FINDINGS: Different modalities have been used to assess myofascial trigger points including ultrasound, microdialysis, electromyography, infrared thermography, and magnetic resonance imaging. Ultrasound is the most promising of these modalities and may be used to identify MTrPs if specific methods are used, but there is no precise description of a gold standard using these techniques, and they have yet to be evaluated in headache patients. Active myofascial trigger points are prevalent in migraine patients. Manual palpation can trigger migraine attacks. All intervention studies aiming at trigger points are positive, but this needs to be further verified in placebo-controlled environments. These findings may imply a causal bottom-up association, but studies of migraine patients with comorbid fibromyalgia syndrome suggest otherwise. Whether myofascial trigger points contribute to an increased migraine burden in terms of frequency and intensity is unclear. Active myofascial trigger points are prevalent in tension-type headache coherent with the hypothesis that peripheral mechanisms are involved in the pathophysiology of this headache disorder. Active myofascial trigger points in pericranial muscles in tension-type headache patients are correlated with generalized lower pain pressure thresholds indicating they may contribute to a central sensitization. However, the number of active myofascial trigger points is higher in adults compared with adolescents regardless of no significant association with headache parameters. This suggests myofascial trigger points are accumulated over time as a consequence of TTH rather than contributing to the pathophysiology. CONCLUSIONS: Myofascial trigger points are prevalent in both migraine and tension-type headache, but the role they play in the pathophysiology of each disorder and to which degree is unclarified. In the future, ultrasound elastography may be an acceptable diagnostic test.

Changes in the bioelectric activity of the trapezius muscle following the thermal effect of red light and infrared radiation.

BACKGROUND: The therapeutic effects of visible light and infrared is especially often used in physiotherapy. OBJECTIVE: The purpose of this study was to determine the effect of exposure to radiation on the motor units activity. METHODS: The study included 29 volunteers of whom the spontaneous and voluntary bioelectric activity of the trapezius muscle was evaluated using surface electromyography (value of average amplitude and frequency), before and immediately after a 15-minute irradiation. Additionally, the range of motion of the cervical spine and trigger points pain sensitivity to the pressure were assessed. RESULTS: No statistically significant changes in the pain sensitivity threshold and the range of motion after the irradiation was applied. On the other hand, a 15-minute exposure to radiation induced an increase in the value of average amplitude of rest-related as well as exercise-related potentials and an increase in the average value of frequency of the right side biopotentials at rest and of both sides for active elevation. CONCLUSIONS: Infrared radiation and visible red light have a stimulating effect on the muscle ability to develop active contraction. It is proposed that the observed changes are associated with the thermal effect of radiation as well as with the so-called extra-visual effects.

Síndrome de dolor miofascial / The myofascial pain syndrome

The myofascial pain syndrome is an entity that is often associated with many of the prevalent pathologies that generate musculoskeletal pain distributed in the different body segments (upper extremities, spine and lower extremities), and may be responsible for the chronification of problem if it is not considered, diagnosed and managed in a comprehensive and timely manner in conjunction with the underlying pathology. (AU)

Histopathological nature of myofascial trigger points at different stages of recovery from injury in a rat model.

OBJECTIVE: To investigate the histopathological nature of myofascial trigger points (MTrPs) or spots (MTrSs) at different stages of recovery from injury in a rat model. METHODS: Forty Sprague-Dawley rats were randomly divided into two groups: a control group (CG) and experimental group (EG). The CG was further randomly subdivided into CG1 and CG2 subgroups. The CG2 was used for palpating the taut band and CG1 as a blank. EG was subdivided into three groups according to recovery times: 4 weeks (4W), 8 weeks (8W) and 12 weeks (12W); these groups consisted of eight rats each. All CG rats received no intervention, whereas the intervention in EG rats was by a blunt strike to the vastus medialis and eccentric exercise for 8 weeks. The taut bands with spontaneous electrical activity were then detected in the muscle to guide a muscle biopsy. The histopathological findings were investigated under optical and electron microscopes in all groups. RESULTS: Under optical microscopy, the differently augmented sizes of round fibres (contracture knots) with deep staining in the transverse section and fusiform shapes in a longitudinal view were clearly seen in CG2 and EGs with a large diameter; the number of contracture knots was significantly more in EGs than in CGs. Under an electron microscope, the mitochondria in EGs significantly decreased with abnormal structures. The sarcomeres were significantly shortened in the 8W and 12W EGs. CONCLUSION: An injury can cause activation of MTrSs in a muscle and an activated level of MTrPs depending on the number of contracture knots in muscle with impaired energy production.

A critical overview of the current myofascial pain literature - June 2017.

We would like to welcome Dr. Li-Wei Chou, MD, PhD as our newly appointed contributing author. Dr. Chou is Assistant Professor at China Medical University in Taichung, Taiwan and he has an impressive publication record with many research studies and book chapters. The current overview includes several articles comparing dry needling (DN) to acupuncture with sharply contrasting points of view. Several basic studies shed further light on the nature of myofascial pain, myalgia, fascia and examination techniques, such as sonoelastography. Neuroimaging studies demonstrated microstructural abnormalities in brain gray matter of chronic myofascial pain patients, which is an important new finding. As usual, many manual TrP papers and DN papers were published in the past several months.

[Definition, classification, clinical diagnosis and prognosis of fibromyalgia syndrome : Updated guidelines 2017 and overview of systematic review articles]. / Definition, Klassifikation, klinische Diagnose und Prognose des Fibromyalgiesyndroms : Aktualisierte Leitlinie 2017 und Übersicht von systematischen Übersichtsarbeiten.

BACKGROUND: The regular update of the guidelines on fibromyalgia syndrome, AWMF number 145/004, was scheduled for April 2017. METHODS: The guidelines were developed by 13 scientific societies and 2 patient self-help organizations coordinated by the German Pain Society. Working groups (n =8) with a total of 42 members were formed balanced with respect to gender, medical expertise, position in the medical or scientific hierarchy and potential conflicts of interest. A systematic search of the literature from December 2010 to May 2016 was performed in the Cochrane library, MEDLINE, PsycINFO and Scopus databases. Levels of evidence were assigned according to the classification system of the Oxford Centre for Evidence-Based Medicine version 2009. The strength of recommendations was achieved by multiple step formalized procedures to reach a consensus. The guidelines were reviewed and approved by the board of directors of the societies engaged in the development of the guidelines. RESULTS AND CONCLUSION: The clinical diagnosis of fibromyalgia syndrome can be established by the American College of Rheumatology (ACR) 1990 classification criteria (with examination of tender points) or without the examination of tender points by the modified preliminary diagnostic ACR 2010 or 2011 criteria.

The effectiveness of Kinesio Taping on pain and disability in cervical myofascial pain syndrome / Efetividade do kinesio taping na dor e incapacidade na síndrome dolorosa miofascial cervical

Abstract Objective: The aim of this study was to investigate the effectiveness of Kinesio Taping and sham Kinesio Taping on pain, pressure pain threshold, cervical range of motion, and disability in cervical myofascial pain syndrome patients (MPS). Methods: This study was designed as a randomized, double-blind placebo controlled study. Sixty-one patients with MPS were randomly assigned into two groups. Group 1 (n = 31) was treated with Kinesio Taping and group 2 (n = 30) was treated sham taping five times by intervals of 3 days for 15 days. Additionally, all patients were given neck exercise program. Patients were evaluated according to pain, pressure pain threshold, cervical range of motion and disability. Pain was assessed by using Visual Analog Scale, pressure pain threshold was measured by using an algometer, and active cervical range of motion was measured by using goniometry. Disability was assessed with the neck pain disability index disability. Measurements were taken before and after the treatment. Results: At the end of the therapy, there were statistically significant improvements on pain, pressure pain threshold, cervical range of motion, and disability (p < 0.05) in both groups. Also there was a statistical difference between the groups regarding pain, pressure pain threshold, cervical flexion-extension (p < 0.05); except cervical rotation, cervical lateral flexion and disability (p > 0.05). Conclusion: This study shows that Kinesio Taping leads to improvements on pain, pressure pain threshold and cervical range of motion, but not disability in short time. Therefore, Kinesio Taping can be used as an alternative therapy method in the treatment of patients with MPS.

Resumo Objetivo Investigar a eficácia do kinesio taping e do taping placebo sobre a dor, limiar de dor à pressão, amplitude de movimento cervical e incapacidade em pacientes com síndrome dolorosa miofascial (SDM) cervical. Métodos: Ensaio clínico randomizado duplo-cego controlado por placebo. Foram alocados em dois grupos, aleatoriamente, 61 pacientes com SDM. O grupo 1 (n = 31) foi tratado com kinesio taping e o grupo 2 (n = 30) foi tratado com taping placebo cinco vezes em intervalos de três dias, durante 15 dias. Além disso, todos os pacientes foram submetidos a um programa de exercícios para o pescoço. Os pacientes foram avaliados em relação à dor, ao limiar de dor à pressão, à amplitude de movimento cervical e à incapacidade. A dor foi avaliada com a escala visual analógica, o limiar de dor à pressão foi medido com um algômetro e a amplitude de movimento cervical ativa foi mensurada com a goniometria. A incapacidade foi avaliada com o Neck Pain Disability Scale. As mensurações foram feitas antes e depois do tratamento. Resultados: No fim do tratamento, houve melhoria estatisticamente significativa na dor, no limiar de dor à pressão, na amplitude de movimento cervical e na incapacidade (p < 0,05) em ambos os grupos. Também houve uma diferença estatisticamente significativa entre os grupos em relação à dor, ao limiar de dor à pressão e à flexão-extensão cervical (p < 0,05); não houve diferença na rotação cervical, flexão lateral cervical e incapacidade (p > 0,05). Conclusão: O kinesio taping leva à melhoria na dor, no limiar de dor à pressão e na amplitude de movimento cervical, mas não na incapacidade em um curto período. Portanto, o kinesio taping pode ser usado como um método de terapia opcional para o tratamento de pacientes com SDM.

Immediate and short-term effects of the combination of dry needling and percutaneous TENS on post-needling soreness in patients with chronic myofascial neck pain

ABSTRACT Background Dry needling (DN) and percutaneous electrical nerve stimulation (PENS) are widely used techniques in the treatment of myofascial pain. Objective To investigate the immediate and short-term effects of the combination of DN and PENS compared to DN alone on the upper trapezius muscle. Method This is a 72-hour follow-up single-blinded randomized controlled trial. Sixty-two volunteer patients with chronic myofascial neck pain with active Myofascial Trigger Points (MTrPs) in the upper trapezius muscle were recruited. Randomization was performed, and 31 patients received DN treatment (DN group) and 31 received DN and PENS (DN+PENS group). The primary outcomes were neck disability index (NDI) and visual analog scale for pain for both post-needling soreness (PNS) and neck pain intensity (NPI). Pressure pain threshold (PPT) and cervical range of motion (CROM) were the secondary outcomes. Results We detected between-group differences in NPI and PNS in favor of the DN+PENS group immediately after treatment. No between-group differences in NDI were observed. Conclusion PENS application after dry needling treatment is more effective than dry needling alone for decreasing soreness in the short term and improving neck pain intensity immediately in patients with myofascial chronic neck pain.

Myofascial pain and fibromyalgia: two different but overlapping disorders.

There is good evidence supporting that people with fibromyalgia syndrome (FMS) exhibit central sensitization. The role of peripheral nociception is under debate in FMS. It seems that widespread pain experienced in FMS is considered multiple regional pains; therefore, several authors proposed that muscles play a relevant role in FMS. Trigger points (TrPs) have long been a contentious issue in relation to FMS. Preliminary evidence reported that the overall spontaneous pain is reproduced by referred pain from active TrPs, suggesting that FMS pain is largely composed of pain arising, at least partially, from TrPs. Finally, there is preliminary evidence suggesting that management of TrPs is able to modulate the CNS and is effective for reducing pain in FMS, although results are conflicting and future studies are clearly needed.

Somatosensory evaluation in Dysfunctional Syndrome patients.

Many chronic pain patients are refractory to treatment, which leads to the suspicion that somehow they are not fully effective and probably some mechanism of pain generation and/or maintenance is still unknown. The aim of this cross-sectional study was to provide evidence-based data on pain mechanisms in different types of chronic pain conditions. Eighty women, with 18-65 years old, were included, divided into four groups: myofascial pain of the masticatory muscles (n = 20), fibromyalgia (n = 20), chronic daily headache and healthy volunteers (n = 20). All patients were submitted to quantitative sensory tests: pressure pain threshold, mechanical detection threshold, mechanical pain threshold, ischaemic pain tolerance, cold pain sensitivity, aftersensation, wind-up ratio and conditioned pain modulation. Current perception threshold was also determined (Neurometer CPT/C - Neurotron). Three different zones were evaluated: trigeminal (masseter muscle), cervical and extratrigeminal (thenar eminence). Data were recorded and subjected to statistical analysis (anova, Tukey and Student's t-tests). Masticatory myofascial pain, fibromyalgia and chronic daily headache individuals presented lower pressure pain thresholds than healthy volunteers (P = 0.00). Chronic daily headache individuals had a significantly higher mechanical detection threshold than healthy volunteers (P = 0.01). Individuals of the symptomatic groups showed lower values for mechanical pain threshold and for ischaemic pain tolerance (P = 0.00) than healthy volunteers. The ability to activate the mechanism of endogenous modulation is impaired in women with fibromyalgia and myofascial pain (P = 0.00). These results reinforce evidence of central sensitisation and impaired endogenous modulation system in individuals with myofascial pain, fibromyalgia and chronic daily headache.

[Myofascial pain syndrome].

OBJECTIVE: To analyze clinical characteristics of pain syndrome in patients with dorsalgia. MATERIAL AND METHODS: Authors studied 43 patients (mean age 41.9±1.2 years), 34 women and 9 men, with acute and subacute chronic back pain. The study included neurological examination, MRI and/or CT of the spine, measurement of anxiety and depression with the Hospital Anxiety and Depression Scale (HADS), The Brief Pain Inventory (BPI) and the McGill Pain Inventory. RESULTS AND CONCLUSION: Chronic myofascial pain syndrome (MFPS) was frequently associated with anxiety-depressive disorders found in patients with cervical and cervical/pectoral pain, fibromyalgia with minimal neurological symptoms and no signs of neural structure compression according to MRI and CT. The results of the study of chronic MFPS should be taken into account in the choice of tactics of treatment of MFPS patients. The use of amelotex in the combination with compligam B in patients with dorsopathy and MFPS is effective together with correction of emotional disorders and treatment with chondroprotectors.

[Migraine and temporomandibular joint dysfunction: mechanisms of comorbidity].

OBJECTIVE: to analyze the frequency of different forms of temporomandibular joint dysfunction (TMJD) in episodic and chronic migraine and to study mechanisms of their comorbidity. MATERIAL AND METHODS: Sixty-three patients with chronic migraine (CM) and 40 patients with episodic migraine (EM) were examined. Anxiety and depression were assessed with the HADS, quality-of-life related to headache was measured with the HIT-6. To evaluate the antinociceptive system function, we studied blink reflex (BR) and nociceptive flexion reflex (NFR). RESULTS: The higher frequency of TMJD was identified in patients with CM compared to those with EM (47.5 and 28.5%, respectively), CM patients more frequently had disturbances related to the myofascial pain syndrome of masticatory muscles. R3 BR and NFR thresholds were significantly decreased in CM patients as well. CONCLUSION: TMJD is a component of the pathogenesis in many patients with CM. Masticatory muscles may generate nociceptive impulses in CNS, ie be a source of peripheral sensitization, that promote pain chronification, including migraine. Dysfunction of masticatory muscles may reflect the central sensitization and disturbance of efferent pain control.

A critical overview of the current myofascial pain literature - October 2015.

The number of publications about myofascial pain and trigger points (TrP) seems to increase every year. In the current overview we include 27 articles published in past months. The Basic Review section includes articles about the presence and characteristics of TrPs in various neck and shoulder muscles, the correlation between referred pain from active TrPs and knee osteoarthritis, and an anatomical study exploring whether the location of TrPs may be related to the nerve innervation of muscles. Zuil-Escobar and colleagues from Spain considered the intra-rater reliability of the identification of latent TrPs in several leg muscles and the possible correlation of TrP and the presence of a lower medial longitudinal arch. In the section on manual approaches, contributing author Rob Grieve and colleagues continue their studies of TrPs in the lower extremity muscles, while Méndez-Rebolledo and colleagues studied the impact of cross taping and compression. Dry needling (DN) continues to be a topic of interest. We included twelve papers addressing a wide range of topics, such as the effectiveness and safety of DN, and the impact of DN on proprioception, spasticity, and fibromyalgia. Two papers investigated the utilization of repetitive transcranial magnetic stimulation and laser on TrPs, The final section on other clinical studies and reviews includes 8 papers. The studies originated in thirteen different countries with Spain leading the charts with 7 contributions to the literature, followed by Brazil with four. As we have mentioned in previous editions of this literature overview, many studies suffer from very small sample sizes, which makes it difficult to reach definitive conclusions. Nevertheless, myofascial pain continues to be a topic of interest to researchers and clinicians around the globe.