A New Unified Theory of Trigger Point Formation: Failure of Pre- and Post-Synaptic Feedback Control Mechanisms.

The origin of the myofascial trigger point (TrP), an anomalous locus in muscle, has never been well-described. A new trigger point hypothesis (the new hypothesis) presented here addresses this lack. The new hypothesis is based on the concept that existing myoprotective feedback mechanisms that respond to muscle overactivity, low levels of adenosine triphosphate, (ATP) or a low pH, fail to protect muscle in certain circumstances, such as intense muscle activity, resulting in an abnormal accumulation of intracellular Ca2+, persistent actin-myosin cross bridging, and then activation of the nociceptive system, resulting in the formation of a trigger point. The relevant protective feedback mechanisms include pre- and postsynaptic sympathetic nervous system modulation, modulators of acetylcholine release at the neuromuscular junction, and mutations/variants or post-translational functional alterations in either of two ion channelopathies, the ryanodine receptor and the potassium-ATP ion channel, both of which exist in multiple mutation states that up- or downregulate ion channel function. The concepts that are central to the origin of at least some TrPs are the failure of protective feedback mechanisms and/or of certain ion channelopathies that are new concepts in relation to myofascial trigger points.

Foci of Segmentally Contracted Sarcomeres in Trapezius Muscle Biopsy Specimens in Myalgic and Nonmyalgic Human Subjects: Preliminary Results.

OBJECTIVE: The myofascial trigger point hypothesis postulates that there are small foci of contracted sarcomeres in resting skeletal muscle. Only one example, in canine muscle, has been published previously. This study evaluated human muscle biopsies for foci of contracted sarcomeres. SETTING: The Departments of Rehabilitation Sciences and Physiotherapy at Ghent University, Ghent, Belgium. SUBJECTS: Biopsies from 28 women with or without trapezius myalgia were evaluated, 14 in each group. METHODS: Muscle biopsies were obtained from regions of taut bands in the trapezius muscle and processed for light and electron microscopy and for histochemical analysis. Examination of the biopsies was blinded as to group. RESULTS: A small number of foci of segmentally contracted sarcomeres were identified. One fusiform segmental locus involved the entire muscle fiber in tissue from a myalgic subject. Several transition zones from normal to contracted sarcomeres were found in both myalgic and nonmyalgic subjects. The distance between Z-lines in contracted sarcomeres was about 25-45% of the same distance in normal sarcomeres. Z-lines were disrupted and smeared in the contracted sarcomeres. CONCLUSIONS: A small number of foci of segmentally contracted sarcomeres were found in relaxed trapezius muscle in human subjects, a confirmation of the only other example of spontaneous segmental contraction of sarcomeres (in a canine muscle specimen), consistent with the hypothesis of trigger point formation and with the presence of trigger point end plate noise.

No. 164-Consensus Guidelines for the Management of Chronic Pelvic Pain.

OBJECTIVE: To improve the understanding of chronic pelvic pain (CPP) and to provide evidence-based guidelines of value to primary care health professionals, general obstetricians and gynaecologists, and those who specialize in chronic pain. BURDEN OF SUFFERING: CPP is a common, debilitating condition affecting women. It accounts for substantial personal suffering and health care expenditure for interventions, including multiple consultations and medical and surgical therapies. Because the underlying pathophysiology of this complex condition is poorly understood, these treatments have met with variable success rates. OUTCOMES: Effectiveness of diagnostic and therapeutic options, including assessment of myofascial dysfunction, multidisciplinary care, a rehabilitation model that emphasizes achieving higher function with some pain rather than a cure, and appropriate use of opiates for the chronic pain state. EVIDENCE: Medline and the Cochrane Database from 1982 to 2004 were searched for articles in English on subjects related to CPP, including acute care management, myofascial dysfunction, and medical and surgical therapeutic options. The committee reviewed the literature and available data from a needs assessment of subjects with CPP, using a consensus approach to develop recommendations. VALUES: The quality of the evidence was rated using the criteria described in the Report of the Canadian Task Force on the Periodic Health Examination. Recommendations for practice were ranked according to the method described in that report (Table 1). RECOMMENDATIONS: The recommendations are directed to the following areas: (a) an understanding of the needs of women with CPP; (b) general clinical assessment; (c) practical assessment of pain levels; (d) myofascial pain; (e) medications and surgical procedures; (d) principles of opiate management; (f) increased use of magnetic resonance imaging (MRI); (g) documentation of the surgically observed extent of disease; (h) alternative therapies; (i) access to multidisciplinary care models that have components of physical therapy (such as exercise and posture) and psychology (such as cognitive-behavioural therapy), along with other medical disciplines, such as gynaecology and anesthesia; G) increased attention to CPP in the training of health care professionals; and (k) increased attention to CPP in formal, high-calibre research. The committee recommends that provincial ministries of health pursue the creation of multidisciplinary teams to manage the condition.

No 164 - Directive clinique de consensus pour la prise en charge de la douleur pelvienne chronique.

OBJECTIF: Améliorer La compréhension de la douleur pelvienne chronique (DPC) et fournir des directives cliniques factuelles qui bénéficieront aux fournisseurs de soins de santé primaires, aux obstétriciens-gynécologues et aux spécialistes de la douleur chronique. FARDEAU DE LA SOUFFRANCE: La DPC est une pathologie débilitante courante qui affecte les femmes. Elle est à l'origine d'importantes souffrances personnelles et de dépenses de santé considérables associées aux interventions, dont de multiples consultations et un grand nombre de traitements médicaux et chirurgicaux. Puisque la pathophysiologie sous-jacente de cet état pathologique complexe est mal comprise, ces traitements n'ont obtenu que des taux de réussite variables. ISSUES: Efficacité des options diagnostiques et thérapeutiques (y compris l'évaluation du dysfonctionnement myofascial); soins multidisciplinaires; un modèle de réadaptation mettant l'accent sur l'obtention d'un fonctionnement supérieur malgré la présence d'une certaine douleur (plutôt que de chercher à obtenir une guérison totale); et utilisation appropriée des opiacés pour le soulagement de la douleur chronique. PREUVES: Des recherches ont été menées dans Medline et la base de données Cochrane en vue d'en tirer les articles de langue anglaise, publiés entre 1982 et 2004, portant sur des sujets liés à la DPC, dont la gestion des soins actifs, le dysfonctionnement myofascial et les options thérapeutiques médicales et chirurgicales. Les membres du comité ont analysé la littérature pertinente, ainsi que les données disponibles tirées d'une évaluation des besoins des personnes présentant une DPC; ils ont fait appel à une approche de consensus pour l'élaboration des recommandations. VALEURS: La qualité des résultats a été évaluée au moyen des critères décrits dans le rapport du Groupe d'étude canadien sur l'examen médical périodique. Les recommandations visant la pratique ont été classées conformément à la méthode décrite dans ce rapport (Tableau 1). RECOMMANDATIONS: Les recommandations visent ce qui suit : (a) compréhension des besoins des femmes présentant une DPC ; (b) évaluation clinique générale ; (c) évaluation pratique des niveaux de douleur ; (d) douleur myofasciale ; (e) médicaments et interventions chirurgicales ; (f) principes de la gestion des opiacés; (g) utilisation accrue de l'imagerie par résonance magnétique (IRM) ; (h) documentation de l'étendue de La maladie constatée au moyen de la chirurgie ; (i) thérapies non conventionnelles; (j) accès à des modèles de soins multidisciplinaires faisant appel à des composantes de physiothérapie (comme l'exercice et la posture) et de psychologie (comme La thérapie cognitivo- comportementale), conjointement avec d'autres disciplines médicales, telles que La gynécologie et l'anesthésie ; (k) attention accrue portée à La DPC dans La formation des professionnels de La sante ; et (l) attention accrue portée à la DPC dans le domaine des recherches officielles et de haut calibre. Le comité recommande que les ministères provinciaux de La Sante prennent des mesures en faveur de la création d'équipes multidisciplinaires pouvant assurer La prise en charge de cette pathologie. Chapitre 2 : Portee et definition de La douleur pelvienne chronique Chapitre 3 : Anamnese, examen physique et évaluation psychologique Chapitre 4 : Explorations Chapitre 5 : Sources de douleur pelvienne chronique Chapitre 6 : Causes urologiques et gastro-intestinales de La douleur pelvienne chronique Chapitre 7 : Dysfonctionnement myofasclal Chapitre 8 : Therapie medicale - résultats en matiere d'efficacite Chapitre 9 : Chirurgie - résultats en matiere d'efficacite Chapitre 11 : Prise en charge multidisciplinaire de La douleur chronique Chapitre 14 : Orientations futures.

Myofascial Trigger Point Pain Syndromes.

Myofascial pain syndromes caused by trigger points (TrPs) in muscle are a common cause of local and generalized pain. Trigger points are hyperirritable zones in contracted bands of muscle, thought to be caused by muscle overload or stress. Stress TrPs have characteristic electromyographic features, and can be visualized with ultrasound and magnetic resonance elastography. Trigger point needling or injection can be effective in inactivating TrP, but correcting triggers is also critical.

Three-dimensional computerized mobilization of the cervical spine for the treatment of chronic neck pain: a pilot study.

BACKGROUND: Manual therapies for chronic neck pain are imprecise, inconsistent, and brief due to therapist fatigue. A previous study showed that computerized mobilization of the cervical spine in the sagittal plane is a safe and potentially effective treatment of chronic neck pain. OBJECTIVE: To investigate the safety and efficacy of computerized mobilization of the cervical spine in a three-dimensional space for the treatment of chronic neck pain. DESIGN: Pilot, open trial. SETTING: Physical therapy outpatient department. PARTICIPANTS: Nine patients with chronic neck pain. INTERVENTIONS: A computerized cradle capable of three-dimensional neck mobilizations was used. Treatment sessions lasted 20 minutes, biweekly, for six weeks. MAIN OUTCOME MEASURES: Visual analog scale (VAS) for pain, cervical range of motion (CROM), neck disability index (NDI), joint position error (JPE), and muscle algometry. RESULTS: Comparing baseline at week one with week six (end of treatment), the VAS scores dropped by 2.9 points (P < 0.01). The six directions of movement studied by the CROM showed a combined increase of 11% (P = 0.01). The NDI decreased significantly from 16 to 10 (P = 0.03), and the JPE decreased significantly from 3.7° to 1.9° (P = 0.047). There was no change in the pressure pain threshold in any muscle tested. There were no significant adverse effects. CONCLUSIONS: These preliminary results demonstrate that this novel, computerized, three-dimensional cervical mobilization device is probably safe. The data also suggest that this method is effective in alleviating neck pain and associated headache, and in increasing the CROM, although the sample size was small in this open trial.

Summaries of the Padua symposium on myofascial pain, fibromyalgia, and fascial pain disorders, June 2023, Aula Falloppio at the Human Anatomy Institute of the University of Padova, Italy.

The International Symposium on Myofascial Pain, Fibromyalgia, and Fascial Pain Disorders was held at the University of Padua, Padua, Italy in June of 2023. This report presents a summary of the presentations from scientists and clinicians from around the world who presented to the symposium. The purpose of this symposium and resultant paper is improve health professional's recognition and understanding of the clinical characteristics, co-morbidities, mechanisms, and treatment strategies for these common conditions to better understand and manage their pain, dysfunction, and quality life.

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

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

Botulinum toxin treatment of myofascial pain: a critical review of the literature.

This is a review of literature relevant to the treatment of myofascial pain syndrome by botulinum injections. The objective is to critically review the studies to see if they are appropriately designed, conducted, and interpreted to provide guidance in the management of myofascial pain. The intent is to better understand the mixed results that these studies have provided. A search was made utilizing PubMed for literature relevant to the use of botulinum toxin in the treatment of myofascial pain. All identifiable series were reviewed, including open label, single-blinded and double-blinded studies, randomized and controlled, or not. In general, small case series of only a few patients were not included unless they made a relevant point and there were no available randomized studies or larger studies. Single case reports were not included. This is not a meta-analysis. The studies were evaluated according to their design and the selection of outcome measurements, and the interpretation of results. The studies were individually critiqued, and an overall assessment and commentary was made of the studies in the field as a whole. Problems that were common to the studies were robust placebo responders, incomplete treatment of a regional myofascial pain syndrome, inappropriate or confounding control populations or treatments, and inappropriate time periods for assessment of outcomes, or misinterpretation of the time-frame of action of botulinum toxin. The studies of the effect of botulinum toxin treatment of myofascial trigger points have had mixed results. However, few studies have been designed to avoid many of the pitfalls associated with a trial of botulinum toxin treatment of trigger points. Better-designed studies may give results that can be used to guide practice based on reliable evidence. At the present time, one must conclude that the available evidence is insufficient to guide clinical practice.

Contracture Knots vs. Trigger Points. Comment on Ball et al. Ultrasound Confirmation of the Multiple Loci Hypothesis of the Myofascial Trigger Point and the Diagnostic Importance of Specificity in the Elicitation of the Local Twitch Response. Diagnostics 2022, 12, 321.

A recent study published in Diagnostics attempted to visualize trigger points and contracture knots with high-definition ultrasound. Based on their findings, the authors reversed the commonly understood meaning of the two terms. However, they did so without providing any convincing evidence. The authors maintained that their sonography images represented trigger points within contracture knots, supporting the multiple loci hypothesis. On review of the paper, both conclusions seem premature and rather speculative.

International, multidisciplinary Delphi consensus recommendations on non-pharmacological interventions for fibromyalgia.

OBJECTIVES: To develop evidence-based expert recommendations for non-pharmacological treatments for pain, fatigue, sleep problems, and depression in fibromyalgia. METHODS: An international, multidisciplinary Delphi exercise was conducted. Authors of EULAR and the Canadian Fibromyalgia Guidelines Group, members of the American Pain Society and clinicians with expertise in fibromyalgia were invited. Participants were asked to select non-pharmacological interventions that could be offered for specific fibromyalgia symptoms and to classify them as either core or adjunctive treatments. An evidence summary was provided to aid the decision making. Items receiving >70% votes were accepted, those receiving <30% votes were rejected and those obtaining 30-70% votes were recirculated for up to two additional rounds. RESULTS: Seventeen experts participated (Europe (n = 10), North America (n = 6), and Israel (n = 1)) in the Delphi exercise and completed all three rounds. Aerobic exercise, education, sleep hygiene and cognitive behavioural therapy were recommended as core treatments for all symptoms. Mind-body exercises were recommended as core interventions for pain, fatigue and sleep problems. Mindfulness was voted core treatment for depression, and adjunctive treatment for other symptoms. Other interventions, namely music, relaxation, hot bath, and local heat were voted as adjunctive treatments, varying between symptoms. CONCLUSIONS: This study provided evidence-based expert consensus recommendations on non-pharmacological treatments for fibromyalgia that may be used to individualise treatments in clinical practice targeting the diverse symptoms associated with fibromyalgia.

The comparative burden of mild, moderate and severe fibromyalgia: results from a cross-sectional survey in the United States.

BACKGROUND: Fibromyalgia (FM) is characterized by chronic, widespread pain, fatigue, and other symptoms; yet few studies have comprehensively assessed its humanistic burden. This observational study evaluates the impact of FM severity on patients' symptoms, health-related quality of life (HRQoL), and productivity in the United States. METHODS: 203 FM subjects were recruited from 20 physician offices. Subjects completed a questionnaire including the EuroQol 5D (EQ-5D), Fibromyalgia Impact Questionnaire (FIQ), Multidimensional Assessment of Fatigue (MAF), Medical Outcomes Study Sleep Scale (MOS-SS), and Hospital Anxiety and Depression Scale (HADS) and questions about demographics, pain and other symptoms, HRQoL and productivity. FIQ total scores were used to define FM severity, with 0- < 39, 39- < 59, and 59-100, representing mild, moderate, and severe FM, respectively. Sites recorded subjects' clinical characteristics and FM treatment on case report forms using medical records. Summary statistics were calculated for continuous variables and frequency distributions for categorical variables. Differences across FM severity groups were evaluated using the Kruskal-Wallis or Chi-square tests. Statistical significance was evaluated at the 0.05 level. RESULTS: Mean (SD) age was 47.9 (10.9); 95% were female. Most (92%) were prescribed medication for FM; 24% and 66% reported moderate and severe FM, respectively. Mean (SD) scores were: 6.3 (2.1) for pain intensity; 0.35 (0.35) for EQ-5D; 30.7 (14.2) for MAF; 57.5 (18.4) for MOS-SS Sleep Problems Index; 10.2 (4.8) for HADS anxiety and 9.4 (4.4) for HADS depression. Subjects with worse FM severity reported significantly increased pain severity, HRQoL, fatigue, sleep disturbance, anxiety and depression (p < 0.001). Overall, 50% of subjects reported some disruption in their employment due to FM; this differed across severity levels (p < 0.001). Employed subjects missed a mean (SD) of 1.8 (3.9) workdays during the past 4 weeks; this also differed across severity levels (p = 0.03). CONCLUSIONS: FM imposes a substantial humanistic burden on patients in the United States, and leads to substantial productivity loss, despite treatment. This burden is higher among subjects with worse FM severity.

Treatment of chronic migraine headache with onabotulinumtoxinA.

Chronic migraine headache remains an exceedingly difficult entity to manage. Treatment of chronic migraine headache with onabotulinumtoxinA has recently been shown to be effective in reducing the severity and frequency of chronic migraine headache, in the PREEMPT trials, a landmark achievement. However, the studies use a primarily fixed dose and site approach to treatment, allowing some individualized injections. However, the authors do not address the issue of myofascial trigger points as potential triggers of migraine that could be inactivated using onabotulinumtoxinA, despite several studies that support the role of myofascial trigger points in initiating some migraine headaches.

Chronic Facial Pain: Trigeminal Neuralgia, Persistent Idiopathic Facial Pain, and Myofascial Pain Syndrome-An Evidence-Based Narrative Review and Etiological Hypothesis.

Trigeminal neuralgia (TN), the most common form of severe facial pain, may be confused with an ill-defined persistent idiopathic facial pain (PIFP). Facial pain is reviewed and a detailed discussion of TN and PIFP is presented. A possible cause for PIFP is proposed. (1) Methods: Databases were searched for articles related to facial pain, TN, and PIFP. Relevant articles were selected, and all systematic reviews and meta-analyses were included. (2) Discussion: The lifetime prevalence for TN is approximately 0.3% and for PIFP approximately 0.03%. TN is 15-20 times more common in persons with multiple sclerosis. Most cases of TN are caused by neurovascular compression, but a significant number are secondary to inflammation, tumor or trauma. The cause of PIFP remains unknown. Well-established TN treatment protocols include pharmacotherapy, neurotoxin denervation, peripheral nerve ablation, focused radiation, and microvascular decompression, with high rates of relief and varying degrees of adverse outcomes. No such protocols exist for PIFP. (3) Conclusion: PIFP may be confused with TN, but treatment possibilities differ greatly. Head and neck muscle myofascial pain syndrome is suggested as a possible cause of PIFP, a consideration that could open new approaches to treatment.