Biochemicals associated with pain and inflammation are elevated in sites near to and remote from active myofascial trigger points

Myofascial Pain Syndrome: An Update on Clinical Characteristics, Etiopathogenesis, Diagnosis, and Treatment

Myofascial pain syndrome (MPS) is a chronic regional pain condition characterized by trigger points-hyperirritable spots within taut bands of muscle fibers that cause both localized and referred pain. The pathogenesis, diagnostic criteria, and classification of MPS are still under investigation, which complicates the development of standardized treatment protocols. Although diagnostic tools have improved, MPS often remains underrecognized due to symptom overlap with other pain disorders, such as fibromyalgia, neuropathic pain, and joint disorders. Factors contributing to its onset and persistence include muscle overuse, postural imbalance, systemic conditions, and psychological and behavioral influences. This narrative review explores the primary risk factors, current hypotheses on pathogenesis, diagnosis and differential diagnosis, and both conventional and emerging treatments. Sufficient evidence supports the use of local anesthetic injections for MPS. Some evidence suggests that dry needling, acupuncture, magnetic stimulation, ultrasound therapy, laser therapy, extracorporeal shock wave therapy, and manual therapy may be effective, particularly compared to sham or placebo. However, non-steroidal anti-inflammatory drugs, diclofenac, botulinum toxin, and transcutaneous electrical nerve stimulation show insufficient evidence, while the effectiveness of muscle relaxants, antidepressants, gabapentin, opioids, topical lidocaine, capsaicin, EMLA cream, and kinesio taping remains inconclusive. Effective management of MPS requires a patient-centered approach that integrates empirically supported and evidence-based treatments tailored to individual needs. This review synthesizes the current understanding of MPS and highlights the need for high-quality research to improve clinical decision-making in managing this complex condition.

Use of corticosteroids for adult chronic pain interventions: sympathetic and peripheral nerve blocks, trigger point injections - guidelines from the American Society of Regional Anesthesia and Pain Medicine, the American Academy of Pain Medicine, the American Society of Interventional Pain Physicians, and the International Pain and Spine Intervention Society

BACKGROUND

There is potential for adverse events from corticosteroid injections, including increase in blood glucose, decrease in bone mineral density and suppression of the hypothalamic-pituitary axis. Published studies note that doses lower than those commonly injected provide similar benefit.

METHODS

Development of the practice guideline was approved by the Board of Directors of American Society of Regional Anesthesia and Pain Medicine with several other societies agreeing to participate. The scope of guidelines was agreed on to include safety of the injection technique (landmark-guided, ultrasound or radiology-aided injections); effect of the addition of the corticosteroid on the efficacy of the injectate (local anesthetic or saline); and adverse events related to the injection. Based on preliminary discussions, it was decided to structure the topics into three separate guidelines as follows: (1) sympathetic, peripheral nerve blocks and trigger point injections; (2) joints; and (3) neuraxial, facet, sacroiliac joints and related topics (vaccine and anticoagulants). Experts were assigned topics to perform a comprehensive review of the literature and to draft statements and recommendations, which were refined and voted for consensus (≥75% agreement) using a modified Delphi process. The United States Preventive Services Task Force grading of evidence and strength of recommendation was followed.

RESULTS

This guideline deals with the use and safety of corticosteroid injections for sympathetic, peripheral nerve blocks and trigger point injections for adult chronic pain conditions. All the statements and recommendations were approved by all participants after four rounds of discussion. The Practice Guidelines Committees and Board of Directors of the participating societies also approved all the statements and recommendations. The safety of some procedures, including stellate blocks, lower extremity peripheral nerve blocks and some sites of trigger point injections, is improved by imaging guidance. The addition of non-particulate corticosteroid to the local anesthetic is beneficial in cluster headaches but not in other types of headaches. Corticosteroid may provide additional benefit in transverse abdominal plane blocks and ilioinguinal/iliohypogastric nerve blocks in postherniorrhaphy pain but there is no evidence for pudendal nerve blocks. There is minimal benefit for the use of corticosteroids in trigger point injections.

CONCLUSIONS

In this practice guideline, we provided recommendations on the use of corticosteroids in sympathetic blocks, peripheral nerve blocks, and trigger point injections to assist clinicians in making informed decisions.

Cardio-Respiratory, Functional and Antalgic Effects of the Integrated Thermal Care Protocol After Breast Cancer Surgery

BACKGROUND

In the cardio-respiratory rehabilitation field, thermal medicine represents an interesting complementary therapy approach. It can aid in complex medical contexts characterized by cardio-respiratory deficiency, functional limitation, and pain determined by the invasiveness of pharmacological and surgical treatments in combination with limited post-surgical physical activity.

METHODS

We investigated the evolution of cardio-respiratory and functional performances following the application of the Integrated Thermal Care (ITC) protocol in 11 mastectomized/quadrantectomized women (mean age of 54 years). The ITC protocol consisted of hydroponic treatments, steam inhalations treatment, hydrokinesitherapy, and manual treatments. Patients were assessed before and after a cycle of 1 h long treatment sessions, which were performed 5 days a week for 4 weeks. The outcomes were measured through the following scales and tests: Piper Fatigue Scale (PIPER), 6-Minute Walking Test (6MWT), Five Times Sit-to-Stand (5STS), Range of Arm Motion (ROM), Disability of the Arm-Shoulder-Hand Scale (DASH), and Numeric Pain Rating Scale (NPRS).

RESULTS

We found appreciable improvements in cardio-respiratory efficiency and in pain perception exemplified by a reduction of PIPER, 5STS, DASH, and NPRS values together with an increase in 6MWT and ROM values.

CONCLUSIONS

We conclude that ITC is a promising rehabilitative tool to enhance cardio-respiratory and functional performance and reduce pain after mastectomy/quadrantectomy.

Efficacy of Phlai (Zingiber montanum) Spray Cool Formula in Managing Upper Trapezius Myofascial Pain Syndrome: A Randomized Controlled Trial

Phlai (Zingiber montanum) has long been valued for its anti-inflammatory and analgesic properties in traditional medicine. This study aimed to develop and assess the physical stability, chemical composition, and clinical efficacy of a novel Phlai spray cool formula (PSCF) compared to a diclofenac spray (DS) in patients with chronic myofascial pain syndrome. The chemical analysis revealed curcumin (28.73 ± 5.73 mg/100 g), β-sitosterol (50.92 ± 1.27 mg/100 g), and lauric acid (38.86 ± 1.72 g/100 g) as key active compounds. PSCF demonstrated stable physicochemical properties, including pH and peroxide value across storage conditions. In a randomized controlled trial involving 66 participants, PSCF and DS groups exhibited comparable reductions in pain intensity, as measured by the Visual Analog Scale (VAS), from baseline to week 2. Both groups also showed significant improvements in neck disability index (NDI), pressure pain threshold (PPT), and cervical range of motion (CROM). By week 2, the increase in CROM for flexion and extension reached 23.54 ± 4.09° and 19.43 ± 3.20°, respectively, with no significant intergroup differences. The SF-36 health survey indicated notable improvements in overall health status and quality of life, particularly in physical and emotional domains. The analgesic effects of PSCF are attributed to the combined action of menthol, β-sitosterol, and curcumin. The study demonstrated that PSCF offers a therapeutic effect comparable to diclofenac spray without adverse reactions, highlighting its potential as an alternative topical analgesic for chronic myofascial pain management.

Stripping versus ligation of vas deferens in microscopic denervation of spermatic cord in men with chronic orchialgia: A multicenter study

BACKGROUND

Microdenervation of the spermatic cord (MSCD) is an effective treatment modality for men with intractable scrotal content pain. For patients not interested in preserving fertility, some centers advocate ligation of the vas during denervation, while others prefer stripping of the vas deferens to preserve the vasal artery, hence preserving vasculature to the testis and possibly decreasing post-operative congestion pain.

OBJECTIVE

To compare outcomes of patients with chronic orchialgia, who underwent MSCD by either stripping or ligating the vas deferens.

MATERIALS AND METHODS

A retrospective chart review of 85 patients who underwent MSCD from 2017-2023 was performed. Patients' demographics including history of prior surgical procedures were recorded. Response to surgery was evaluated as either complete resolution of pain, partial resolution of pain, or no improvement in pain.

RESULTS

Eighty-five patients underwent MSCD with a median (interquartile range, IQR) age of 36 (25.5-46.5) years and median duration of pain of 16 (6-31) months. Thirty-seven patients underwent stripping of vas, while 48 underwent ligation of vas during MSCD. Median follow up was 12 months. Twenty-one (43.5%) patients had prior inguinal scrotal surgery in the ligation group compared to 5 (13.5%) in the stripping group, p = 0.003. The etiology of pain was similar between the groups. The response to MSCD between the two groups was similar, 67.6% of patients who underwent stripping had complete resolution of pain versus 66.7% of those who had ligation (p = 0.968), with similar rates of post-operative complications (p-value = 0.132).

CONCLUSIONS

In men with intractable chronic scrotal content pain with no interest in preserving fertility, ligation, or stripping of the vas deferens yields similar outcomes with regard to pain resolution. Both techniques are safe with no reports of any testicular atrophy.

Prevalence and location of myofascial trigger points in dogs with osteoarthritis

Introduction

This study was designed to determine the prevalence of myofascial pain and the location of myofascial trigger points (MTPs) in dogs with osteoarthritis.

Methods

Thirty-five dogs were selected and examined for the presence of MTPs using palpation. Assessments were performed independently by two examiners. Correlations between age, MTP number and location, and the site of osteoarthritis were also investigated.

Results and discussion

Thirty out of 35 dogs (86%) had at least one MTP and only 5 (14%) had none. A total of 177 MTPs were identified in dogs in this sample. The prevalence of MTPs was higher in the longissimus thoracicae (40% and 43%; left and right side respectively), followed by the quadriceps femoris (40% and 31%), longissimus lumborum (20% and 23%), gluteus medius and deltoid muscles (14%; left side only), and the pectineus muscle (11%; right side only). The number of osteoarthritic joints was not correlated with the number of MTPs or age. However, age was positively correlated with the number of muscles affected by MTPs. Correlations between the presence of MTPs in muscles surrounding and the affected joints were also lacking.

Conclusion

The prevalence of MTPs in dogs with osteoarthritis is high. Myofascial TPs are positively correlated with age in these patients. The subjective nature of palpation is a major limitation in myofascial pain assessment. Appropriate training and use of standardized diagnostic criteria are recommended.

Migraine/Headache "Tender Spots" Represent Referred Pain From Nerve Compression/Neuromas and Are Not "Trigger Points"

ABSTRACT

To minimize confusion in description of the clinical examination of the patient with migraine/headaches and implement peripheral nerve concepts into the surgical approach to treating the patient with migraines, the historical origin of the phrase "trigger point" is explored. The symptoms of migraine/headache are due to stimulation of the cranial/peripheral nerve being interpreted as due to stimulation of the meningeal innervation. Use of the phrase "extraction of trigger points" is discouraged in favor of either neurolysis of a compressed nerve or resection of a neuroma, depending upon the peripheral nerve pathology.

Effectiveness of adding dry needling of the upper trapezius muscle to the usual physiotherapy for managing chronic neck pain: A randomized controlled trial with a 7-week follow-up

BACKGROUND

Myofascial pain syndrome (MPS) is a chronic condition caused by sensitive pressure regions within the muscles known as myofascial trigger points (MTrPs).

OBJECTIVE

The purpose of this randomized controlled trial (RCT) was to assess the effectiveness of adding dry needling (DN) to activate MTrPs in the upper trapezius muscle compared with usual physiotherapy among individuals with chronic neck pain.

METHODS

Thirty participants were recruited from a private clinic in Saudi Arabia. Their mean age was 29.7 ± 4.4 years. The subjects were randomized into two groups: the experimental group (application of DN to the MTrPs coupled with usual physiotherapy (n = 15)) and the control group (usual physiotherapy alone (n = 15)). The primary outcomes were pain (assessed using the visual analog scale) and disability (Neck Disability Index), and the secondary outcomes were neck active range of motion (AROM; assessed using cervical ROM) and depression (Beck's Depression Inventory).

RESULTS

Significant between-group difference in pain intensity was observed immediately post-intervention. Participants in the experimental group had significantly higher pain (mean difference = 1.27, 95% confidence interval [CI] 0.20, 2.33, p = 0.022, Cohen's d = 0.889) than those in the control group. There was no significant difference between both groups in pain intensity during the follow-up. There were no between-group differences in disability immediately post-intervention. However, there was a between-group difference in disability at follow-up; participants in the experimental group had significantly lower disability (mean difference = -3.13, 95%CI -5.07, -1.20, p = 0.003, Cohen's d = 1.211) than those in the control group. Immediately post-intervention, the experimental group showed greater flexion AROM compared to the control group, with no differences in other AROM measures. At follow-up, the experimental group exhibited significantly higher neck AROM in extension, flexion, right and left side bending, and lower depression, while no differences were observed in right- and left-rotation AROMs between groups.

CONCLUSIONS

The addition of DN to standard physiotherapy effectively improved disability, AROM (extension, flexion, and side bending), and depression among patients with chronic neck pain.

Fu's subcutaneous needling promotes axonal regeneration and remyelination by inhibiting inflammation and endoplasmic reticulum stress

Fu's subcutaneous needling (FSN) is a traditional Chinese acupuncture procedure used to treat pain-related neurological disorders. Moreover, the regulation of inflammatory cytokines may provide a favorable environment for peripheral nerve regeneration. In light of this, FSN may be an important novel therapeutic strategy to alleviate pain associated with peripheral neuropathy; however, the underlying molecular mechanisms remain unclear. This study revealed that patients who had osteoarthritis with peripheral neuropathic pain significantly recovered after 1 to 2 weeks of FSN treatment according to the visual analog scale, Western Ontario and McMaster Universities Osteoarthritis Index, Lequesne index, walking speed, and passive range of motion. Similarly, we demonstrated that FSN treatment in an animal model of chronic constriction injury (CCI) significantly improved sciatic nerve pain using paw withdrawal thresholds, sciatic functional index scores, and compound muscle action potential amplitude tests. In addition, transmission electron microscopy images of sciatic nerve tissue showed that FSN effectively reduced axonal swelling, abnormal myelin sheaths, and the number of organelle vacuoles in CCI-induced animals. Mechanistically, RNA sequencing and gene set enrichment analysis revealed significantly reduced inflammatory pathways, neurotransmitters, and endoplasmic reticulum stress pathways and increased nerve regeneration factors in the FSN+CCI group, compared with that in the CCI group. Finally, immunohistochemistry, immunoblotting and enzyme-linked immunosorbent assay showed similar results in the dorsal root ganglia and sciatic nerve. Our findings suggest that FSN can effectively ameliorate peripheral neuropathic pain by regulate inflammation and endoplasmic reticulum stress, thereby determine its beneficial application in patients with peripheral nerve injuries.

Efficacy and Safety of Ultrasound-Guided Acupotomy Versus Celecoxib in Patients with Thoracodorsal Myofascial Pain Syndrome: A Randomized Controlled Trial

Objective: To evaluate the efficacy and safety of ultrasound-guided acupotomy (UgA) for the treatment of thoracodorsal myofascial pain syndrome (TDMPS) and monitor its mid-term efficacy at 3 months after treatment. Methods: A 3-week, evaluator-blinded randomized clinical trial was conducted among 100 patients with TDMPS (visual analogue scale [VAS] score > 3) in the outpatient clinic of the Department of Orthopaedics of the Second Affiliated Hospital of Anhui University of Traditional Chinese Medicine, with a 3-month follow-up starting after completion of treatment. These patients were randomly assigned to receive UgA (n = 50) or oral celecoxib (n = 50). Recruitment was conducted between January 2021 and July 2022. The primary outcome was the VAS score, and the secondary outcomes included the Oswestry Disability Index (ODI), Pain Anxiety Symptoms Scale (PASS), and TNF-α and IL-1β levels. Outcome data were collected at baseline, week 3 (post-treatment) and week 15 (follow-up). Results: Compared with that in the celecoxib group, the pain in the UgA group was alleviated more strongly, with an adjusted mean group difference of -0.69 (95% CI,-1.07 to -0.31 after multiple imputation) at week 3 and -1.96 (95% CI,-2.33 to -1.59 after multiple imputation) at week 15 (p < 0.001 for overall group × time interaction). Both groups exhibited improvements in the ODI and PASS scores at weeks 3 and 15, but these improvements were significantly greater in the UgA group (p < 0.05). At week 3, the TNF-α and IL-1 levels were significantly lower in both groups, but celecoxib was more effective (p < 0.05). Results from analyses with multilevel multiple imputation for missingness were similar. Conclusion: UgA led to greater and safer alleviation of pain, dysfunction, and pain anxiety in patients treated with TDMPS than did celecoxib and had a durable 3-month efficacy but was inferior to celecoxib in reducing the level of inflammatory factors. These findings may prompt clinicians to recommend UgA as an alternative and supplementary therapy for pain management in patients with TDMPS.

The effects of high intensity laser therapy and dry needling on clinical signs in females with upper trapezius muscle active trigger points: A single blinded randomized clinical trial

OBJECTIVE

One of the main contributors to musculoskeletal pain syndromes are myofascial trigger points (MTrPs), which are characterized by discomfort, tenderness, and restricted range of motion (ROM). In this study, patients with upper trapezius myofascial pain syndrome had their pain intensity, cervical range of motion, and disability evaluated in relation to the effectiveness of high intensity laser therapy and dry needling.

METHODS

32 participants with active upper trapezius myofascial trigger points were split into two groups at random: one group received high intensity laser treatment (n = 16), while the other received dry needling (n = 16). All participants got relevant intervention twice weekly throughout the three weeks of treatment sessions (5 sessions). Before and after the intervention, the cervical range of movements, disability and Pain intensity were all assessed by iPhone inclinometer & goniometer, neck disability index and visual analog scale respectively.

RESULTS

The visual analog scale and neck disability index significantly reduced post-intervention in both groups (P < 0.001). Moreover, the cervical range of motions significantly increased in both groups (P < 0.05). However, there was no significant difference in pain intensity, neck disability index and the cervical range of motions between the two groups (P > 0.05).

CONCLUSION

Active myofascial trigger points in the upper trapezius muscle may be effectively treated with dry needling or high-intensity laser therapy.

Ultrasound imaging and guidance in the management of myofascial pain syndrome: a narrative review

Myofascial pain syndrome (MPS) is a common musculoskeletal disorder characterized by muscle pain, tenderness, and trigger points. Ultrasonography has emerged as a key tool for diagnosing and treating MPS owing to its ability to provide precise, minimally invasive guidance. This review discusses the use of ultrasonography in various approaches to evaluate and manage MPS. Studies have shown that shear-wave sonoelastography can effectively assess muscle elasticity and offer insights into trapezius stiffness in patients with MPS. Ultrasound-guided interfascial hydrodissection, especially with visual feedback, has demonstrated effectiveness in treating trapezius MPS. Similarly, ultrasound-guided rhomboid interfascial plane blocks and perimysium dissection for posterior shoulder MPS have significantly reduced pain and improved quality of life. The combination of extracorporeal shockwave therapy with ultrasound-guided lidocaine injections has been particularly successful in reducing pain and stiffness in trapezius MPS. Research regarding various guided injections, including dry needling, interfascial plane blocks, and fascial hydrodissection, emphasizes the importance of ultrasonography for accuracy and safety. Additionally, ultrasound-guided delivery of local anesthetics and steroids to the quadratus lumborum muscle has shown lasting pain relief over a 6-month period. Overall, these findings highlight the pivotal role of ultrasonography in the assessment and treatment of MPS.

Effect of dry needling on pain and central sensitization in women with chronic pelvic pain: A randomized parallel-group controlled clinical trial

Chronic pelvic pain (CPP) is a debilitating problem in women with clear evidence of myofascial dysfunction. It seems that Myofascial trigger points (MTrPs) contribute to the development of central sensitization (CS). This study aimed to investigate the effect of dry needling on pain and CS in women with CPP. Thirty-six women with CPP participated in this randomized controlled clinical trial and randomly assigned into three groups: dry needling group (DNG), placebo needling group (PNG) and control group (CG). The DNG received five sessions of DN using the "static needling", the PNG received non-penetrating method, and the CG did not receive any intervention. Assessment of outcomes including central sensitization inventory (CSI), short-form McGill pain questionnaire (SF-MPQ), electroencephalography (EEG), conditioned pain modulation (CPM), salivary cortisol concentration, 7-item general anxiety disorder scale (GAD-7), pain catastrophizing scale (PCS), and SF-36 questionnaire was performed pre-intervention, post-intervention, and three months post-intervention by a blind examiner. The result showed a significant group-by-time interaction for CSI, SF-MPQ, and PCS. There was a significant decrease in CSI score in post-intervention and three-months post-intervention compare to pre-intervention in the DNG and PNG. SF-MPQ-PPI score in DNG significantly decreased post-intervention. PCS-Total score decreased significantly post-intervention in DNG and PNG. No significant group-by-time interactions were observed for other variables. EEG results showed regional changes in the activity of frequency bands in both eye closed and eye open conditions. It seems that DN can affect central pain processing by removing the source of peripheral nociception. Trial registration: Iranian Registry of Clinical Trials (IRCT20211114053057N1, registered on: December 03, 2021. https://irct.behdasht.gov.ir/search/result?query=IRCT20211114053057N1).

Research Progress on the Experimental Model and Underlying Mechanistic Studies of Tension-Type Headaches

PURPOSE OF REVIEW

Tension-type headaches (TTH) significantly diminish patients' quality of life and increase absenteeism, thereby imposing a substantial economic burden. Animal models are essential tools for studying disease mechanisms and drug development. However, until now, little focus has been placed on summarizing the animal models of TTH and associated mechanistic studies. This narrative review discusses the current animal models of TTH and related mechanistic studies to provide insights into the pathophysiological mechanisms of and treatments for TTH.

RECENT FINDINGS

The primary method for constructing an animal model of TTH involves injecting a solution of pain relievers, such as adenosine triphosphate, nerve growth factor, or a high concentration of salt solution, into the neck to initiate harmful cervical muscle responses. This model enables the examination of the interaction between peripheral muscles and central sensitization, which is crucial for understanding the pathophysiology of TTH. Mechanistic studies based on this model have investigated the effect of the P2X receptor antagonist, P2X7 receptor blockade, the P2Y1 receptor agonist 2-MESADP, P2Y1 receptor antagonist MRS2179, nitric oxide synthase inhibitors, and acetylsalicylic acid. Despite notable advancements, the current model of TTH has limitations, including surgical complexity and the inability to replicate chronic tension-type headache (CTTH). To gain a more comprehensive understanding and develop more effective treatment methods, future studies should focus on simplifying surgical procedures, examining other predisposing factors, and establishing a model for chronic TTH. This will offer a deeper insight into the pathophysiological mechanism of TTH and pave the way for improved treatment approaches.

Mouth opening, jaw disability, neck disability, pressure pain thresholds, and myofascial trigger points in patients with disc displacement with reduction: A descriptive and comparative study

OBJECTIVE

To assess jaw and neck function, pressure pain threshold (PPT), and the presence of trigger points (TrPs) in disc displacement with reduction (DDWR) subjects compared to healthy subjects.

METHODS

One hundred DDWR subjects and 100 matched controls were studied. Clinical evaluations included demographic data, range of motion, jaw and neck disability, PPT, and muscle TrPs.

RESULTS

DDWR subjects have limited pain-free opening limitation (p < 0.001), jaw and neck disability limitation (p < 0.001), and higher presence of active and latent TrPs limitation (p < 0.001) compared to healthy subjects.

CONCLUSION

DDWR subjects present a limited pain-free mouth opening, higher jaw and neck disability, lower PPT, and major presence of active and latent TrPs compared to healthy subjects. Cervical spine and TMJ evaluation and treatment should be considered in DDWR patients.

Integrated neuromuscular inhibition technique versus spray and stretch technique in neck pain patients with upper trapezius trigger points: a randomized clinical trial

OBJECTIVE

This study aimed to investigate the difference between the integrated neuromuscular inhibition technique (INIT) and spray and stretch technique in patients with neck pain and upper trapezius active trigger points. Methods: A convenience sample of 60 patients with neck pain and active trigger points were recruited from physiotherapy students and allocated randomly to three groups INIT plus stretching exercise spray and stretch technique plus stretching exercise, and stretching exercise only. Treatment was three times per week for four weeks. Pain intensity by visual analogue scale (VAS), pain pressure threshold (PPT), neck disability by Arabic neck disability index (ANDI), and muscle amplitude in the form of root mean square (RMS) by electromyography (EMG) were measured at baseline and after four weeks. Results: Between groups analysis; the results revealed statistical significant difference between three groups after four weeks of intervention as p =0.0001. Within the group analysis, post hoc tests reported improvement at all variables in both INIT and spray and stretch technique groups with mean differences 64.5 and 65.1 in VAS, 20 and 18.15 in ANDI, -1.45 and -0.81 in PPT, and 2.47 and 1.88 in muscle amplitude, respectively. But there was no statistically significant difference in stretching only group in all variables except VAS.

CONCLUSION

Both INIT and spray and stretch techniques had a clinical and statistical effects on pain, function, PPT, and RMS. According to results, there were statistical significant differences between INIT and spray and stretch groups at post-treatment in all variables except VAS with more favor to INIT group, but there were no clinical differences between INIT and spray and stretch groups.

Assessment of the Effects of Sphingosine Kinase 1/Sphingosine-1-Phosphate on Microangiogenesis at Rat Myofascial Trigger Points Using Contrast-Enhanced Ultrasonography

Purpose

Few studies have assessed the effects of sphingosine kinase 1/sphingosine-1-phosphate (SPHK1/S1P) on microangiogenesis at rat myofascial trigger points (MTrPs) using contrast-enhanced ultrasonography (CEUS). This study aimed to address these deficiencies. Here, we investigated the effects of SPHK1/S1P on MTrP microangiogenesis and the value of CEUS in evaluating these effects.

Methods

Forty Sprague‒Dawley rats were subdivided into two groups: control and MTrP groups. MTrPs were established by 8 weeks of the strike procedure combined with eccentric motion and 4 weeks of recovery. All rats were euthanized after having undergone CEUS with an overdose of pentobarbital sodium. MTrP and control tissue samples were removed for haematoxylin and eosin (H&E) staining and transmission electron microscopy (TEM) imaging. The tissue was dehydrated, cleared, and embedded before sectioning. The sections were then incubated overnight at 4°C, and immunohistochemistry was carried out with primary antibodies including rabbit anti-CD31, rabbit anti-SPHK1and rabbit anti-S1PR1.

Results

MTrP rats exhibited spontaneous electrical activity (SEA) and a local twitch response (LTR) during electromyography (EMG) examination. The CEUS time-intensity curves (TICs) showed that the perfusion intensity in the MTrPs and surrounding tissue area was increased, with faster perfusion than in normal sites, while the TICs in the control group slowly increased and then slowly decreased. The correlation coefficient between the microvessel density (MVD) and sphingosine 1-phosphate receptor 1 (S1PR1) was 0.716 (p <0.01). Spearman correlation analysis revealed that Spearman's rho (ρ) values between the MVD and peak intensity (PI), between the MVD and area under the curve (AUC), and between the MVD and SPHK1 were > 0.5 (p <0.05), > 0.7 (p <0.01), and > 0.7 (p <0.01), respectively.

Conclusion

CEUS is valuable for detecting microangiogenesis within MTrPs, and SPHK1/S1P plays an important role in promoting MTrP tissue microangiogenesis.

The Influence of Mobility Training on the Myofascial Structures of the Back and Extremities

BACKGROUND

The subject of the study was the effect of a multicomponent program (Mobility Routine) on muscular and fascial stiffness, flexibility, subjective well-being, and body perception.

METHODS

The assumption was that high physical stress affects myofascial structures and joint range of motion. The assessment of myofascial stiffness employed a Shear Wave Elastography. The joint flexibility, pressure pain threshold, and subjective experiences with regard to tension, pain, and general discomfort were documented.

RESULTS

In the CT group, a greater increase in stiffness was measured in fewer measurement areas compared to the MR group. MR demonstrated superior gains in flexibility compared to CT. Both groups experienced significant reductions in pain, tension, and discomfort. In conclusion, repetitive motion patterns akin to CT lead to increased myofascial stiffness, whereas MR yields more balanced stiffness development, compensates for asymmetries, and improves body awareness.

CONCLUSIONS

Hence, this study highlights the advantages of mobility training over Crosstrainer exercises and provides valuable insights for the recommendation of training regimens aiming at the enhancement of musculoskeletal functionality and overall well-being.

Mechanical Needling With Sterile Water Versus Lidocaine Injection for Lumbar Spinal Stenosis

Study Design: This was a retrospective observational study that assessed the clinical outcome of ageing patients who received ultrasound-guided (USG) mechanical needling with sterile water injection. In addition, the clinical outcome of age-and gender matched patients randomly selected from patients who received needling with sterile water was compared to the patients injected with lidocaine in a 1:1 ratio.Objective: This present study aimed to explore the clinical effects of USG mechanical needling with sterile water injection for lumbar spinal stenosis (LSS).Methods: The data was extracted from the medical records of ageing patients with LSS who received USG injection at the lumbosacral spine by the first author. Low back pain or axial pain, and leg pain or radicular pain were assessed by the visual analogue scale, and gait ability with walking distance were obtained at six different time points.Results: A total of 4328 medical records were examined. Four thousand two hundred and twenty-eight ageing patients received mechanical needling with sterile water injection and found the efficacy lasted up to 6 months. One hundred patients were compared with 100 patients who received lidocaine injection. Those who received lidocaine had pain returned at 3 months and 6 months post-injection.Conclusions: USG mechanical needling with sterile water injection could help relieve axial and radicular pain for at least 6 months. Removal of calcification and fibrosis as well as reduction of sensitization are all possible mechanisms.

Associations of tissue damage induced inflammatory plasticity in masseter muscle with the resolution of chronic myalgia

Gene plasticity during myogenous temporomandibular disorder (TMDM) development is largely unknown. TMDM could be modeled by intramuscular inflammation or tissue damage. To model inflammation induced TMDM we injected complete Freund's adjuvant (CFA) into masseter muscle (MM). To model tissue damage induced TMDM we injected extracellular matrix degrading collagenase type 2 (Col). CFA and Col produced distinct myalgia development trajectories. We performed bulk RNA-seq of MM to generate gene plasticity time course. CFA initiated TMDM (1d post-injection) was mainly linked to chemo-tacticity of monocytes and neutrophils. At CFA-induced hypersensitivity post-resolution (5d post-injection), tissue repair processes were pronounced, while inflammation was absent. Col (0.2U) produced acute hypersensitivity linked to tissue repair without inflammatory processes. Col (10U) generated prolonged hypersensitivity with inflammatory processes dominating initiation phase (1d). Pre-resolution phase (6d) was accompanied with acceleration of expressions for tissue repair and pro-inflammatory genes. Flow cytometry showed that immune processes in MM was associated with accumulations of macrophages, natural killer, dendritic and T-cells, further confirming our RNA-seq findings. Altogether, CFA and Col treatments induced different immune processes in MM. Importantly, TMDM resolution was preceded with muscle cell and extracellular matrix repairs, an elevation in immune system gene expressions and distinct immune cell accumulations in MM.

Ketogenic Diet: A Nutritional Therapeutic Tool for Lipedema?

PURPOSE OF REVIEW

This review aims to provide an overview of the current evidence on the efficacy, also considering the anti-inflammatory properties and safety of very low-calorie ketogenic diet (VLCKD) as a potential treatment for lipedema, particularly in the context of obesity.

RECENT FINDINGS

Lipedema is a chronic disease characterized by abnormal and painful fat buildup on the legs and/or arms. It is often misdiagnosed as obesity or lymphedema. However, although lipedema and obesity can coexist, unlike obesity, lipedema usually affects the legs and thighs without affecting the feet or hands, and the abnormal deposition of adipose tissue in lipedema is painful. The current lifestyle interventions are often unsuccessful in the management of lipedema. There is no consensus on the most effective nutritional approach for managing lipedema. Recent studies have suggested that VLCKD may be an effective treatment for lipedema, demonstrating that it is also superior to other nutritional approaches such as Mediterranean diet or intermittent fasting. Lipedema is a chronic and debilitating disease characterized by abnormal and painful accumulation of adipose tissue in the legs. VLCKD has been shown to be an effective treatment for lipedema, especially in the context of obesity, due to its anti-inflammatory properties. However, further research is needed to determine the long-term safety and efficacy of VLCKD as a treatment for lipedema.

Self-Massage Techniques for the Management of Pain and Mobility With Application to Resistance Training: A Brief Review

ABSTRACT

MacLennan, M, Ramirez-Campillo, R, and Byrne, PJ. Self-massage techniques for the management of pain and mobility with application to resistance training: a brief review. J Strength Cond Res 37(11): 2314-2323, 2023-Fascial restrictions that occur in response to myofascial trigger points (MTrP), exercise-induced muscle damage (EIMD), and delayed onset of muscle soreness (DOMS) cause soft tissue to lose extensibility, which contributes to abnormal muscle mechanics, reduced muscle length, and decrements in joint range of motion (ROM) and actively contributes to musculoskeletal pain. Resistance training and in particular, weightlifting movements have unique mobility requirements imperative for movement efficacy and safety with ROM restrictions resulting in ineffective volume and intensity tolerance and dampened force output and power, which may lead to a failed lift or injury. Self-massage (SM) provides an expedient method to promote movement efficiency and reduce injury risk by improving ROM, muscular function, and reducing pain and allows athletes to continue to train at their desired frequency with minimal disruption from MTrPs-associated adverse effects. Thus, the aim of this review was to determine the efficacy of various self-massage tools in managing pain and mobility and to explore the potential benefits of SM on resistance training performance. Many SM devices are available for athletes to manage ROM restrictions and pain, including differing densities of foam rollers, roller massagers, tennis balls, and vibrating devices. To attenuate adverse training effects, a 10-to-20-minute bout consisting of 2-minute bouts of SM on the affected area may be beneficial. When selecting a SM device, athletes should note that foam rollers appear to be more effective than roller massagers, with vibrating foam rollers eliciting an increased reduction to pain perception, and tennis balls and soft massage balls were shown to be efficacious in targeting smaller affected areas.

Dry Needling for Arthrogenic Muscle Inhibition of Quadriceps Femoris in Patients after Reconstruction of Anterior Cruciate Ligament: a Protocol for a Randomized Controlled Trial

Background

: Dry needling (DN) is recommended as a therapeutic modality for various neuromusculoskeletal disorders. No study has been performed on the impact of DN on arthrogenic muscle inhibition (AMI) after anterior cruciate ligament reconstruction (ACLR). This study protocol is aimed to investigate the impacts of DN on AMI of quadriceps femoris, corticomotor, and spinal reflex excitability in patients with ACLR.

Methods

: A double-blind, between-subject, randomized, controlled trial will be conducted to measure changes in AMI after DN. Twenty-four subjects with ACLR will be recruited to receive a DN or a sham DN, providing that they met the inclusion criteria. Three sessions of DN on the quadriceps femoris will be applied during a one-week period. The primary outcome measures are the active motor threshold, motor evoked potential, and Hmax - Mmax ratio. The secondary outcomes are the International Knee Documentation Committee subjective knee form questionnaire score and maximum quadriceps isometric torque. Data will be collected at baseline, immediately after the first session, after the third session, and at the one-month follow-up visit.

Discussion

: The results of this study will provide preliminary evidence regarding the effects of DN on AMI of quadriceps femoris in patients with ACLR.

A model for personalized diagnostics for non-specific low back pain: the role of the myofascial unit

Low back pain (LBP) is the leading cause of disability worldwide. Most LBP is non-specific or idiopathic, which is defined as symptoms of unknown origin without a clear specific cause or pathology. Current guidelines for clinical evaluation are based on ruling out underlying serious medical conditions, but not on addressing underlying potential contributors to pain. Although efforts have been made to identify subgroups within this population based on response to treatment, a comprehensive framework to guide assessment is still lacking. In this paper, we propose a model for a personalized mechanism-based assessment based on the available evidence that seeks to identify the underlying pathologies that may initiate and perpetuate central sensitization associated with chronic non-specific low back pain (nsLBP). We propose that central sensitization can have downstream effects on the "myofascial unit", defined as an integrated anatomical and functional structure that includes muscle fibers, fascia (including endomysium, perimysium and epimysium) and its associated innervations (free nerve endings, muscle spindles), lymphatics, and blood vessels. The tissue-level abnormalities can be perpetuated through a vicious cycle of neurogenic inflammation, impaired fascial gliding, and interstitial inflammatory stasis that manifest as the clinical findings for nsLBP. We postulate that our proposed model offers biological plausibility for the complex spectrum of clinical findings, including tissue-level abnormalities, biomechanical dysfunction and postural asymmetry, ecological and psychosocial factors, associated with nsLBP. The model suggests a multi-domain evaluation that is personalized, feasible and helps rule out specific causes for back pain guiding clinically relevant management. It may also provide a roadmap for future research to elucidate mechanisms underlying this ubiquitous and complex problem.

A comparison between effectiveness of gluteal trigger point and epidural steroid injection in lumbosacral canal stenosis patients: a randomized clinical trial

BACKGROUND

Lumbosacral Spinal Stenosis (LSS) is a degenerative spine disease and a major cause of pain and disability, especially in geriatrics. Primary symptom control in patients with LSS includes conservative treatment and non-surgical methods. In this study, we aimed to compare the effect of steroid injection via epidural and gluteal trigger point techniques.

METHODS

Patients aged 40-75 years old who had pain and other clinical signs of spinal stenosis in the last 6 months were included in our study and divided into two groups of gluteal trigger point (TP) or epidural steroid injection (ESI). The patients were evaluated based on the visual analog scale (VAS), Roland-Morris Disability Questionnaire (RDQ), Oswestry Disability Index (ODI), and the Quebec back pain disability scales during their pre-injection period and 2 weeks after follow-ups till 8 weeks. A P value of less than 0.05 was considered significant.

RESULTS

A total of 44 patients were included in our study. The TP group had a significant decrease in comparison with their follow-ups; however, in the epidural group, the significant decrease was only observed compared to the pre-injection period and the scores did not have any significant decreases after the second week regarding the ODI, RQM, and VAS scales. The TP group demonstrated significantly higher scores of decreases of ODI and Quebec score compared to the epidural group at weeks 4 and 8. Regarding RQM, the TP groups demonstrated significantly higher scores of decreases compared to the epidural group at weeks 2, 4 and 8. (p < 0.001 p = 0.008, and p < 0.001, respectively).

CONCLUSION

Both epidural and TP steroid injection significantly reduced the patients' pain and improved their QoL and function; however, more satisfactory results were observed in the TP group during the patients' follow-ups, while the epidural group demonstrated only statistically significant improvement during the short-term follow-up.

Evidence for an association of serum microanalytes and myofascial pain syndrome

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Headache frequency and neck pain are associated with trapezius muscle T2 in tension-type headache among young adults

BACKGROUND

Tension-type headache (TTH) is the most prevalent primary headache disorder. Neck pain is commonly associated with primary headaches and the trigemino-cervical complex (TCC) refers to the convergence of trigeminal and cervical afferents onto neurons of the brainstem, thus conceptualizes the emergence of headache in relation to neck pain. However, no objective biomarkers exist for the myofascial involvement in primary headaches. This study aimed to investigate the involvement of the trapezius muscles in primary headache disorders by quantitative magnetic resonance imaging (MRI), and to explore associations between muscle T2 values and headache frequency and neck pain.

METHODS

This cohort study prospectively enrolled fifty participants (41 females, age range 20-31 years): 16 subjects with TTH only (TTH-), 12 with mixed-type TTH plus migraine (TTH+), and 22 healthy controls (HC). The participants completed fat-suppressed T2-prepared three-dimensional turbo spin-echo MRI, a headache diary (over 30 days prior to MRI), manual palpation (two weeks before MRI), and evaluation of neck pain (on the day of MRI). The bilateral trapezius muscles were manually segmented, followed by muscle T2 extraction. Associations between muscle T2 and the presence of neck pain as well as the number of days with headache (considering the 30 days prior to imaging using the headache calendar) were analyzed using regression models (adjusting for age, sex, and body mass index).

RESULTS

The TTH+ group demonstrated the highest muscle T2 values (right side: 31.4 ± 1.2 ms, left side: 31.4 ± 0.8 ms) as compared to the TTH- group or HC group (p < 0.001). Muscle T2 was significantly associated with the number of headache days (β-coefficient: 2.04, p = 0.04) and the presence of neck pain (odds ratio: 2.26, p = 0.04). With muscle T2 as the predictor, the area under the curve for differentiating between HC and the TTH+ group was 0.82.

CONCLUSIONS

Increased T2 of trapezius muscles may represent an objective imaging biomarker for myofascial involvement in primary headache disorders, which could help to improve patient phenotyping and therapy evaluation. Pathophysiologically, the increased muscle T2 values could be interpreted as a surrogate of neurogenic inflammation and peripheral sensitization within myofascial tissues.

Muscle spindles as pain receptors

Background

Muscle membranes have a sensation of pain, but within the muscle tissue, the origin of pain is unclear. We present a hypothesis that the pain receptors of the muscle tissue are situated principally in the muscle spindles. A recent report reintroduced that 'end plate spikes' in needle electromyography (EMG) are fusimotor unit potentials of the intrafusal muscle fibres, and thus represent a marker of muscle spindles.

Methods

We studied four relaxed muscles with 50 EMG needle insertions in each and mapped the appearance of pain and spontaneous EMG activity.

Results

Only 4.0% of the needle insertions in muscle tissue elicited pain. However, needle insertions in local active points showing 'end plate spikes' and, thus, fusimotor unit potentials of the muscle spindles elicited pain in 86% of the insertions, whereas needle insertions in points without 'end plate spikes' elicited pain in only 1.0% of the insertions (p<0.001).

Conclusions

Muscle spindles have pain receptors. The extrafusal muscle tissue is practically pain-free for the needle insertions. This demonstrates a scarcity of extrafusal pain receptors. How this observation is put into perspective with the muscle pain syndromes was discussed.

Association of inflammation and tissue damage induced biological processes in masseter muscle with the resolution of chronic myalgia

Biological processes linked to intramuscular inflammation during myogenous temporomandibular disorder (TMDM) are largely unknown. We mimicked this inflammation by intra-masseteric muscle (MM) injections of complete Freund’s adjuvant (CFA) or collagenase type 2 (Col), which emulates tissue damage. CFA triggered mechanical hypersensitivity at 1d post-injection was mainly linked to processes controlling chemotactic activity of monocytes and neutrophils. At 5d post-CFA, when hypersensitivity was resolved, there was minimal inflammation whereas tissue repair processes were pronounced. Low dose Col (0.2U) also produced acute orofacial hypersensitivity that was linked to tissue repair, but not inflammatory processes. High dose Col (10U) triggered prolonged orofacial hypersensitivity with inflammatory processes dominating at 1d post-injection. At pre-resolution time point (6d), tissue repair processes were underway and a significant increase in pro-inflammatory gene expressions compared to 1d post-injection were detected. RNA-seq and flow cytometry showed that immune processes in MM were linked to accumulation of macrophages, natural killer and natural killer T cells, dendritic cells and T-cells. Altogether, CFA and Col treatments induced different immune processes in MM. Importantly, orofacial hypersensitivity resolution was preceded with repairs of muscle cell and extracellular matrix, an elevation in immune system gene expression and accumulation of distinct immune cells in MM.

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.

Virtual reality therapy for myofascial pain: Evolving towards an evidence-based non-pharmacologic adjuvant intervention

Myofascial pain syndrome (MPS) is a highly prevalent and burdensome cause of pain globally, representing a major focus of chronic pain management. Management of MPS is highly variable, with therapies ranging from interventional approaches to physical therapy. Virtual reality (VR) is a novel form of therapy being actively explored as an adjuvant to procedural sedation in the acute pain setting, and increasingly as a means of chronic pain management through programs that facilitate pain education, physical therapy and mindfulness, among other approaches. However, to date, there are minimal clinical studies assessing VR therapy within the context of MPS treatments. Given the existing volume of work published in the acute pain setting and the translational work exploring VR and neuroplasticity in chronic pain, we make the case here that it is an appropriate time to consider exploring VR therapy as a non-pharmacological adjuvant treatment for MPS.

Comparison of Manual Therapy Technique to Therapeutic Exercise in the Treatment of Patients With Subacromial Impingement Syndrome: A Randomized Clinical Trial

OBJECTIVE

The purpose of this study was to compare the effects of manual therapy to therapeutic exercise on shoulder pain, disability, and range of motion (ROM) in patients with subacromial impingement syndrome (SAIS).

METHODS

Sixty patients with SAIS were randomly assigned into the manual therapy (MT) and therapeutic exercise (TE) groups. Patients in the MT group were treated with joint mobilization, which was applied to the glenohumeral, acromioclavicular, sternoclavicular and scapulothoracic joints, and trigger point (TrP) inactivation using ischemic compression. Patients in the TE group performed therapeutic exercises. Shoulder pain, disability and active ROM (elevation, external rotation, and internal rotation) were assessed by the visual analog scale, the Shoulder Pain and Disability Index, and a goniometer, respectively. The outcomes were measured at baseline, after the intervention, and 1 month after the intervention.

RESULTS

After the treatment, both groups had significant improvements in shoulder pain, disability, and ROM (P < .05). The MT group experienced a greater reduction in shoulder pain than the TE group (P < .001). However, in disability and ROM, both groups exhibited similar improvements in post-treatment and follow-up periods.

CONCLUSION

Both MT and TE were effective in improving shoulder pain, disability, and ROM in patients with SAIS. Greater improvement in shoulder pain was observed in the MT group.

Research Trends of Acupuncture Therapy on Myofascial Pain Syndrome from 2000 to 2022: A Bibliometric Analysis

Background

Acupuncture has been widely used to relieve myofascial pain syndromes (MPS) in many countries. However, the bibliometric analysis of the global application of acupuncture for MPS remains unknown.

Purpose

The present study aims to evaluate the research trends and hot spots of acupuncture for MPS.

Methods

Literatures about acupuncture for MPS from 2000 to 2022 were obtained from the Web of Science. CiteSpace (6.1.R3) was used to analyze the number of publications, countries, institutions, authors, cited journals, cited authors, cited references and keywords.

Results

A total of 403 records were included in the final analysis. The total number of publications increased but with some fluctuations. The Pain was the most cited journals. The most productive country and institution were USA, and China Medicine University, respectively. Liwei Chou was the most prolific author, and Simons DG ranked first in the cited author. In the ranking of frequency and centrality in cited references, the first article was published by Tough EA and Simons DG, respectively. The keyword of "acupuncture" ranked first in frequency, "double blind" ranked first in centrality. "Meta-analysis" was the keyword with the strongest citation burst. There were three hot topics in this field, including "the clinical feature of MPS", "measure of intervention" and "research method". The mechanism of acupuncture on MPS was one of the main research directions.

Conclusion

This study reveals that acupuncture was more and more acceptable, while the cooperation between different countries, institutions and authors should be strengthened. The researches of therapeutic effect and mechanism were the main research directions. More high-quality clinical trials are needed to confirm the therapeutic effect of acupuncture for MPS, and more studies to unify the acupuncture parameters such as frequency, duration, and intensity. More basic studies are needed to elucidate the precise mechanism of acupuncture for MPS.

Effects of Trigger Point Dry Needling on Strength Measurements and Activation Levels of the Gluteus Medius: A Quasi-Experimental Randomized Control Study

Background

Latent trigger points have been identified as a source of impaired muscle function giving rise to a reduction in force production and alterations in muscle activation patterns and movement efficiency. There is limited investigation into the effectiveness of a treatment in reducing these clinical manifestations.

Purpose

To investigate whether the application of trigger point dry needling (TDN) to latent trigger points within the gluteus medius musculature affected strength measurements and muscle activation levels immediately following intervention.

Design

Quasi experimental, single group, pretest-posttest, randomized control study.

Methods

A control and an intervention side were randomly assigned for each participant (N = 39). Hand held dynamometer (HHD) force measurements and raw surface electromyography (sEMG) amplitude readings were recorded during maximal volitional isometric contractions of the gluteus medius in two separate positions before and after application of TDN. Comparison of within and between group data were conducted.

Results

A statistically significant interaction between time (pre-TDN to post-TDN) and groups (intervention side and control side), p < 0.001 was found for HHD measurements in both positions. Post hoc analysis revealed a statistically significant difference (p < 0.001) for all comparisons in the side lying neutral (SL0) position, while statistically significant differences (p < 0.001) were found for pre and post-TDN measurements within intervention side as well as between the intervention and control side for post-TDN measurements in the side lying internal rotation (SLIR) position. For sEMG amplitude measurements, statistically significant differences were found only in the SL0 position for within group comparisons on the intervention side (p = 0.009) and for between group comparisons for post-TDN measurements (p = 0.002).

Conclusion

Application of TDN to latent trigger points within the gluteus medius can significantly increase gluteus muscle force production immediately following intervention while reducing the level of muscle activation required during contraction.

Level of Evidence

Level 2.

Lipedema: Insights into Morphology, Pathophysiology, and Challenges

Lipedema is an adipofascial disorder that almost exclusively affects women. Lipedema leads to chronic pain, swelling, and other discomforts due to the bilateral and asymmetrical expansion of subcutaneous adipose tissue. Although various distinctive morphological characteristics, such as the hyperproliferation of fat cells, fibrosis, and inflammation, have been characterized in the progression of lipedema, the mechanisms underlying these changes have not yet been fully investigated. In addition, it is challenging to reduce the excessive fat in lipedema patients using conventional weight-loss techniques, such as lifestyle (diet and exercise) changes, bariatric surgery, and pharmacological interventions. Therefore, lipedema patients also go through additional psychosocial distress in the absence of permanent treatment. Research to understand the pathology of lipedema is still in its infancy, but promising markers derived from exosome, cytokine, lipidomic, and metabolomic profiling studies suggest a condition distinct from obesity and lymphedema. Although genetics seems to be a substantial cause of lipedema, due to the small number of patients involved in such studies, the extrapolation of data at a broader scale is challenging. With the current lack of etiology-guided treatments for lipedema, the discovery of new promising biomarkers could provide potential solutions to combat this complex disease. This review aims to address the morphological phenotype of lipedema fat, as well as its unclear pathophysiology, with a primary emphasis on excessive interstitial fluid, extracellular matrix remodeling, and lymphatic and vasculature dysfunction. The potential mechanisms, genetic implications, and proposed biomarkers for lipedema are further discussed in detail. Finally, we mention the challenges related to lipedema and emphasize the prospects of technological interventions to benefit the lipedema community in the future.

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

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

Dexmedetomidine inhibits abnormal muscle hypertrophy of myofascial trigger points via TNF-α/ NF-κB signaling pathway in rats

Myofascial pain syndrome (MPS) is a chronic pain disorder with inflammation-related primarily characterized by the presence of myofascial trigger points (MTrPs). Myocyte enhancer factor 2C (MEF2C) is involved in the occurrence of a variety of skeletal muscle diseases. However, it is not yet clear if MEF2C is involved in MTrPs. The purpose of this study was to investigate whether MEF2C was involved in the inflammatory pathogenesis of MTrPs. In the present study, we used RNA sequencing (RNA-seq) to compare the differential expression of myocyte enhancer factor 2C (MEF2C) in healthy participants and MTrPs participants. The widely used rat MTrPs model was established to research the upstream and downstream regulatory mechanism of MEF2C and found that MEF2C was significantly increased in patients with MTrPs. Dexmedetomidine (Dex) was injected intramuscularly in the MTrPs animal to assess its effects on MEF2C. The expression of MEF2C protein and mRNA in skeletal muscle of rats in the MTrPs group were up-regulated. In addition, the expression of TNF- α, p-P65, MLCK, and Myocilin (MyoC) was up-regulated and the mechanical pain threshold was decreased. Peripheral TNF- α injection significantly decreased the mechanical pain threshold and increased the expression of p-P65, MLCK, MEF2C, and MyoC in healthy rats. Maslinic acid increased the mechanical pain threshold and inhibited the expression of p-P65, MLCK, MEF2C, and MyoC. In addition, peripheral injection of DEX in MTrPs rats also inhibited the expression of TNF- α, p-P65, MLCK, MEF2C, and MyoC. These results suggest that MEF2C is involved in the inflammatory pathogenesis of MTrPs and DEX serves as a potential therapeutic strategy for the treatment of MPS.

Intramuscular Electrical Stimulation to Trigger Points: Insights into Mechanisms and Clinical Applications-A Scoping Review

Intramuscular electrical stimulation (IMES) is a modality used by clinicians to treat myofascial pain. Recent studies have shown positive results for the use of IMES on pain outcomes, yet studies investigating the potential mechanisms of IMES directly to trigger points (TrPs) are lacking. We performed a scoping review of the literature to summarize the current evidence from human and animal studies on the mechanisms of IMES to the TrP location, and to identify gaps in the existing literature. Electronic literature searches were conducted across five databases from inception to 15 August 2022, including PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Allied and Complementary Medicine Database (AMED), Scopus and Cochrane Register of Controlled Trials. Four studies met our full criteria for inclusion in this review. Three studies assessed the effects of IMES to TrPs on human subjects with MPS, and only one study used an animal model with experimentally generated TrPs. Based on the results of the included studies, IMES within a TrP region was reported to normalize muscle blood flow, decrease endplate noise of the TrP and elicit antinociceptive effects, at least partially, through engaging supraspinal descending pain inhibitory systems. At present, no clinical implications can be determined on the use of IMES to TrPs due to the limited amount and quality of the available evidence. Further studies investigating the clinical effectiveness and also underlying mechanisms of IMES to TrPs are clearly needed.

Effectiveness of Dry Needling and Ischemic Trigger Point Compression in the Gluteus Medius in Patients with Non-Specific Low Back Pain: A Randomized Short-Term Clinical Trial

BACKGROUND

The presence of latent myofascial trigger points (MTrPs) in the gluteus medius is one of the possible causes of non-specific low back pain. Dry needling (DN) and ischemic compression (IC) techniques may be useful for the treatment of these MTrPs.

METHODS

For this study, 80 participants were randomly divided into two groups: the dry needling group, who received a single session of DN to the gluteus medius muscle plus hyperalgesia (n = 40), and the IC group, who received a single session of IC to the gluteus medius muscle plus hyperalgesia (n = 40). Pain intensity, the pressure pain threshold (PPT), range of motion (ROM), and quality of life were assessed at baseline, immediately after treatment, after 48 h, and one week after treatment.

RESULTS

Statistically significant differences were shown between the two groups immediately after the intervention, showing a decrease in PPT (p < 0.05) in the DN group and an increase in PPT in the IC group. These values increased more and were better maintained at 48 h and after one week of treatment in the DN group than in the IC group. Quality of life improved in both groups, with greater improvement in the DN group than in the IC group.

CONCLUSIONS

IC could be more advisable than DN with respect to UDP and pain intensity in the most hyperalgesic latent MTrPs of the gluteus medius muscle in subjects with non-specific low back pain, immediately after treatment. DN may be more effective than IC in terms of PPT, pain intensity, and quality of life in treating latent plus hyperalgesic gluteus medius muscle MTrPs in subjects with non-specific low back pain after 48 h and after one week of treatment.

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.

Trigger Points and Contracture/Contraction Knots: What's in a Name? Reply to Dommerholt, J.; Gerwin, R.D. 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"

We are responding to the comment by Dommerholt and Gerwin that we have reverse-defined "myofascial trigger point" (MTrP) and "contracture/contraction knot." In attempting to maintain philosophical agreement with specific and implied aspects of their integrated hypothesis of trigger-point formation (namely a MTrP being ischemic and hypoxic), we referred to the MTrP as the small hyperechoic signal rather than the larger hypoechoic (and therefore hyperperfused) structure surrounding it. It was never our intent to re-define nor contribute to confusion. In making this concession with respect to Dommerholt and Gerwin's preferred nomenclature, however, we must instead now reconcile what we image as a hypoechoic (and therefore hyperperfused) MTrP with it being concurrently hypoxic.

Dry Needling Alone or in Combination with Exercise Therapy versus Other Interventions for Reducing Pain and Disability in Subacromial Pain Syndrome: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis examined the effects of dry needling alone or in combination with exercise therapy for reducing pain and disability in people with subacromial pain syndrome. Systematic searches of randomized clinical trials (RCTs) were performed in five different databases. A meta-analysis was carried out with the data obtained, and the risk of bias and quality of the studies was assessed using the Cochrane ROB 2.0 and GRADE tools. Finally, five RCTs (n = 315) were included in the meta-analysis and qualitative analysis. Our results determine that dry needling alone or combined with exercise therapy showed improvements in pain in the short-term (5RCTs: SMD: -0.27; [-0.49, -0.05]; low-quality) and mid-term (4RCTs: SMD: -0.27; [-0.51, -0.04]; low-quality) compared to a range of interventions. However, no differences were shown for disability at short-term (3 RCTs: SMD: -0.97; [-2.04, 0.11]; very-low quality) and mid-term (3 RCTs: SMD: -0.85; [-1.74, 0.04]; very-low quality). Dry needling alone or in combination with exercise therapy may result in a slight reduction in pain in the short-term and mid-term. However, the evidence about the effect of this therapy on disability in the short- or mid-term is very uncertain compared to the range of interventions analyzed in this systematic review (Registration: INPLASY202260112).

Effects on Neuromuscular Function After Ischemic Compression in Latent Trigger Points in the Gastrocnemius Muscles: A Randomized Within-Participant Clinical Trial

OBJECTIVE

The purpose of this study was to evaluate changes in neuromuscular function, pain perception, and basic physical properties in latent myofascial trigger points (TrPs) after a single treatment session of ischemic compression in the gastrocnemius muscle.

METHODS

A randomized within-participant clinical trial with a blinded assessor was conducted. Twenty-nine asymptomatic volunteers with latent gastrocnemius-muscle TrPs were bilaterally explored. Each extremity was randomly assigned to the control group (no treatment) or the experimental group (90 seconds of ischemic compression over each TrP). Neuromuscular function of the gastrocnemius muscle was assessed using a MyotonPro. Muscle flexibility was analyzed using the lunge test and the passive ankle range of motion. The strength was determined with a handheld dynamometer (MicroFET2). Pain perception was analyzed with a 0-to-10 numerical pain rating scale and determination of pressure pain thresholds over each latent TrP.

RESULTS

The results revealed a reduction of 15.8% in pain perception and an increment of pressure tolerance of 9.9% without pain in the treatment group. Changes in muscle flexibility (active and passive) and most parameters for neuromuscular response (rigidity, elasticity, and relaxation) were also observed, but they were not significantly different between groups. The clinical effect sizes were moderate for pain perception (d = 0.69), pressure pain threshold (d = 0.78), muscle tone (d = 0.51), and elasticity (d = 0.54) in favor of the treated extremity. Small clinical effect sizes were observed for muscle physical outcomes.

CONCLUSION

The present study shows that the use of a single session of ischemic compression for latent gastrocnemius-muscle TrPs improved some sensory outcomes. The effects on ankle range of motion and neuromuscular responses were inconclusive.

Effect of ischemic compression on myofascial pain syndrome: a systematic review and meta-analysis

Background

Myofascial pain syndrome (MPS) is a condition with local and referred pain characterized by trigger points (taut bands within the muscle). Ischemic compression is a noninvasive manual therapy technique that has been employed for the treatment of MPS in past decades. However, little attention has been devoted to this topic.

Objectives

The present review was designed to explore the efficacy of ischemic compression for myofascial pain syndrome by performing a descriptive systematic review and a meta-analysis to estimate the effect of ischemic compression on MPS.

Methods

A systematic review and meta-analysis concerning randomized controlled trials (RCTs) with myofascial pain subjects who received ischemic compression versus placebo, sham, or usual interventions. Five databases (PubMed, The Cochrane Library, Embase, Web of Science, Ovid) were searched from the earliest data available to 2022.1.2. The standardized mean difference (SMD) and the 95% confidence interval (CI) were used for statistics. Version 2 of the Cochrane risk of tool 2 (RoB 2) was used to assess the quality of the included RCTs.

Results

Seventeen studies were included in the systematic review, and 15 studies were included in the meta-analysis. For the pressure pain threshold (PPT) index, 11 studies and 427 subjects demonstrated statistically significant differences compared with the control at posttreatment (SMD = 0.67, 95% CI [0.35, 0.98], P < 0.0001, I² = 59%). For visual analog scale (VAS) or numeric rating scale (NRS) indices, 7 studies and 251 subjects demonstrated that there was no significant difference between ischemic compression and controls posttreatment (SMD = − 0.22, 95% CI [− 0.53, 0.09], P = 0.16, I² = 33%).

Conclusion

Ischemic compression, as a conservative and noninvasive therapy, only enhanced tolerance to pain in MPS subjects compared with inactive control. Furthermore, there was no evidence of benefit for self-reported pain. The number of currently included subjects was relatively small, so the conclusion may be changed by future studies. Big scale RCTs with more subjects will be critical in future.