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Clinical Implication of Latent Myofascial Trigger Point

Abstract

Myofascial trigger points (MTrPs) are hyperirritable points located within a taut band of skeletal muscle or fascia, which cause referred pain, local tenderness and autonomic changes when compressed. There are fundamental differences between the effects produced by the two basic types of MTrPs (active and latent). Active trigger points (ATrPs) usually produce referred pain and tenderness. In contrast, latent trigger points (LTrPs) are foci of hyperirritability in a taut band of muscle, which are clinically associated with a local twitch response, tenderness and/or referred pain upon manual examination. LTrPs may be found in many pain-free skeletal muscles and may be "activated" and converted to ATrPs by continuous detrimental stimuli. ATrPs can be inactivated by different treatment strategies; however, they never fully disappear but rather convert to the latent form. Therefore, the diagnosis and treatment of LTrPs is important. This review highlights the clinical implication of LTrPs.
... Latent MTrP, unlike active MTrP, is not symptomatic during periods of rest and activity. Symptoms only typically appear when compression is applied, similar to conditions with active trigger points (Celik and Mutlu, 2013). ...
... No difference was found between non-MTrP groups either. Latent MTrP may cause limitations in the joint range of motion and overloading of muscle and joint structures by disrupting motor activation patterns and reciprocal inhibition mechanisms (Celik and Mutlu, 2013). In addition, an incompatible actin and myosin relationship in latent MTrP may lead to a weakness without atrophy in skeletal muscles (Turgut, 2015). ...
... Different treatment modalities have been defined in MTrP, and a multimodal approach is recommended. Invasive treatment approaches such as dry needling, local anesthetic injection, joint manipulation, ischemic compression method, friction massage, post isometric relaxation, and electrotherapy have been presented in the literature for the treatment of latent MTrP (Celik and Mutlu, 2013). However, the need for these treatments can be eliminated if the awareness regarding the concept of "primary protection" is raised; this can also be beneficial for the health system and society. ...
Article
Introduction We hypothesized that latent MTrPs might decrease gluteus medius muscle strength in healthy individuals. This study aimed to investigate the relationship between latent MTrPs and gluteus medius muscle strength in a group of healthy adults. Methods Forty-eight healthy men were included in the study. Trigger point examination for the gluteus medius was performed bilaterally. Subjects with one or more trigger points on the dominant side and those without any trigger point were assigned to two groups. Muscle strength for the gluteus medius was assessed with a manual muscle tester using the “break test” technique on both sides. For statistical analysis, the independent sample t-test was used to compare the intergroup differences. Results The latent MTrP group demonstrated lower abduction muscle strength in the dominant gluteus medius. Moreover, the latent MTrP group showed higher abduction muscle strength in the non-dominant gluteus medius (p < 0.05). Intergroup comparison revealed that gluteus medius abduction muscle strength on the dominant side was higher in the non-latent MTrP group (p < 0.05). Conclusion Latent MTrP may cause joint movement limitation, overload by affecting motor activation patterns and reciprocal inhibition mechanisms. Outcomes of the current study revealed that gluteus medius abduction strength values below 9.7 kg could be associated with latent MTrP with high sensitivity and low specificity. It is imperative to note that the latent MTrP of gluteus medius muscle, which has a critical role in the lumbopelvic junction, should not be ignored in clinical practice, and treatment should be applied when detected.
... Myofascial pain is a clinical syndrome derived from musculoskeletal pain, which presents with a referred component and is diagnosed by rigorous examination to locate myofascial trigger points (MTrPs) [1][2][3]. MTrPs are clinically defined as a hyperirritable nodule of spot tenderness located in a taut band of skeletal muscle which is tender and palpable through physical examination [4]. A recent study carried out by Li et al. [5] stated that the diagnosis of MTrPs is mostly based on the presence of three criteria, either stand-alone or combined: spot tenderness, referred pain and local twitch response (LTR). ...
... The use of these criteria combined provide a more reliable diagnosis, as it is known that the reliability of each criterion is associated with the analyzed muscle [6]. In addition to physical examination, taut bands can be objectively characterized by magnetic resonance [7], and the irritability caused by MTrPs can be showed by electromyography [3,8]. Nevertheless, an objective standard diagnostic of MTrPs is still needed [5]. ...
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This study aims to analyze the effects of Dry Needling (DN) for the release of myofascial trigger points (MTrPs) in the triceps surae muscles (TSM). A systematic review was performed up to February 2022 in PubMed, PEDro, Scopus, CENTRAL, and Web of Science. Selection criteria were studies involving subjects older than 18 years presenting MTrPs in the TSM, without any concomitant acute or chronic musculoskeletal conditions; DN interventions applied to the MTrPs of the TSM; and results on pain, range of motion (ROM), muscle strength, muscle stiffness, and functional outcomes. The PEDro scale was used to assess the methodological quality of the studies, and the Risk of Bias Tool 2.0 to assess risk of bias. A total of 12 studies were included in the systematic review, involving 426 participants. These results suggest that DN of MTrPs in TSM could have a positive impact on muscle stiffness and functional outcomes. There are inconclusive findings on musculoskeletal pain, ROM, and muscle strength. Significant results were obtained in favor of the control groups on pressure pain thresholds. Despite the benefits obtained on muscle stiffness and functional performance, the evidence for the use of DN of MTrPs in the TSM remains inconclusive.
... Myofascial pain syndrome (MPS) is a condition characterized by local and referred pain as well as autonomic symptoms, which are all produced by myofascial trigger points (MTrPs). The most widely accepted hypothesis regarding the pathogenesis of MTrPs is sustained sarcomere contraction due to excessive acetylcholine release at the neuromuscular junction on the basis of overuse or muscle injury [1][2][3][4][5][6]. Pain is produced by the contracted muscle tissue compressing the blood vessels, causing local ischemia and vasoneuroactive Patients were enrolled in this study from January 2016 through June 2019 at the Department of Rehabilitation Medicine, Faculty of Medicine, Chulalongkorn University, and King Chulalongkorn Memorial Hospital, Bangkok, Thailand. ...
... Patients with MTrPs who were diagnosed by A.S. using the criteria specified in [6] were considered eligible for this study. The inclusion criteria were as follows: (1) age between 20 and 25 years; (2) diagnosis of only one active MTrP in the UTM on either the left or the right side; (3) mild to moderate pain intensity at baseline (VAS pain between 3 and 6; with VAS = 0 representing no pain at all and VAS = 10 representing maximum, intolerable pain); (4) ability to attend the hospital during the treatment and follow-up assessments; and (5) willingness to sign the informed consent form. The exclusion criteria were as follows: (1) fixed contractures or deformities of the shoulder and neck; (2) diseases of bones and joints; (3) clinical signs of myopathy and neuropathy; (4) treatment of MTrPs in the UTM with injection of lidocaine, ESWT, injection of any other local anesthetics or Botulinum neurotoxin, dry needling, drugs or any other treatment during a period of three months before inclusion in this study; (5) previous surgery of the shoulder and neck; (6) epilepsy; (7) intellectual disability; (8) infection, tumor, ulcer, or skin condition at the treatment site. ...
Article
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Background and Objectives: This study tested the hypothesis that treatment of myofascial trigger points (MTrPs) in the upper trapezius muscle (UTM) with repeated injection of 1% lidocaine results in better alleviation of muscular stiffness and soreness as well as improved metabolism in the hypercontracted MTrP area than treatment with radial extracorporeal shock wave therapy (rESWT). Materials and Methods: A single-blinded, prospective, randomized controlled trial was conducted on patients suffering from MTrPs in the UTM. Thirty patients were treated with repeated injection of 2 mL of 1% lidocaine (three injections; one injection per week). Another 30 patients were treated with rESWT (three treatment sessions; one treatment session per week; 2000 radial extracorporeal shock waves per treatment session; positive energy flux density = 0.10 mJ/mm2). The primary outcome measure was pain severity using the VAS score. The secondary outcome measures included muscle elasticity index, pressure pain threshold and neck disability index. Evaluation was performed at baseline (T1), 15–30 min after the first treatment in order to register immediate treatment effects (T2), before the second treatment (i.e., one week after baseline) (T3) and one week after the third treatment (i.e., four weeks after baseline) (T4). Results: There were no statistically significant differences in the primary and secondary outcome measures between the patients in the lidocaine arm and the patients in the rESWT arm at T1 and T4. Within the arms, the mean differences of all outcomes were statistically significant (p < 0.001) when comparing the data obtained at T1 with the data obtained at T3 and the data obtained at T4. Conclusions: The results of this pilot study suggest that the use of rESWT in patients with MTrPs in the UTM is safe and leads to reduced pain and improved muscle elasticity, pressure pain threshold and neck disability index, without adverse effects. Larger trials are necessary to verify this. Clinicians should consider rESWT instead of injections of lidocaine in the treatment of MTrPs in the UTM.
... Latent MTrPs can be ''silent'', not noticed for a long time and unnoticeable during physical examination, only becoming active in either major acute events (spine trauma, accident) or minor events (bladder or vaginal infection, emotional stress) [7]. While there is controversy about the existence of trigger points, electrophysiological and microanalysis studies support the existence of discrete microenvironments in these areas that underlie the generation of pain [8][9][10]. Trigger points in the PFMs can cause pain referred to different areas, including the suprapubic region, posterior and inner thighs, buttocks, lower back, vagina, anorectum, urethra, pubic bone, vagina, and coccyx [11]. ...
Article
Context Despite the high prevalence of a myofascial pain component in chronic pelvic pain (CPP) syndromes, awareness and management of this component are lacking among health care providers. Objective To summarize the current state of the art for the management of myofascial pain in chronic primary pelvic pain syndromes (CPPPS) according to scientific research and input from experts from the European Association of Urology (EAU) guidelines panel on CPP. Evidence acquisition A narrative review was undertaken using three sources: (1) information in the EAU guidelines on CPP; (2) information retrieved from the literature on research published in the past 3 yr on myofascial pelvic pain; and (3) expert opinion from panel members. Evidence synthesis Studies confirm a high prevalence of a myofascial pain component in CPPPS. Examination of the pelvic floor muscles should follow published recommendations to standardize findings and disseminate the procedure. Treatment of pelvic floor muscle dysfunction and pain in the context of CPP was found to contribute to CPP control and is feasible via different physiotherapy techniques. A multidisciplinary approach is the most effective. Conclusions Despite its high prevalence, the myofascial component of CPP has been underevaluated and undertreated to date. Myofascial pain must be assessed in all patients with CPPPS. Treatment of the myofascial pain component is relevant for global treatment success. Further studies are imperative to reinforce and better define the role of each physiotherapy technique in CPPPS. Patient summary Pain and inflammation of the body’s muscle and soft tissues (myofascial pain) frequently occurs in pelvic pain syndromes. Its presence must be evaluated to optimize management for each patient. If diagnosed, myofascial pain should be treated.
... On other hand, latent myofascial trigger points are tender points produces local twitch response, local or referred pain on manual examination and is not familiar or known by the patient. 3 MTrP is considered as primary cause of most musculoskeletal pathologies. A research study conducted in united states reported that 30 to 85% of patients has MTrP as primary source of pain (1). ...
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Objective: The aim of this study was to compare the effect of dry needling and sustained pressure in the lumbar paraspinal trigger points in terms of pain threshold and muscle length. Methodology: Fifty patients were randomly allocated in experimental and control group having lumbar paraspinal muscle trigger points. Experimental and control groups received dry needling and sustained pressure along with stretching and strengthening exercises. Patients were assessed at 1st pre-and 4th post session using Oswestry disability index, paraspinal muscle length, visual analogue scale and pain pressure threshold using algometer. Results: Pain pressure threshold and visual analogue scale showed significant results whereas Oswestry disability index and paraspinal muscle length showed no significant results (P>0.01). Analysis within the group showed significant difference from pre-to post intervention level (P<0.01) in terms of pain pressure threshold, paraspinal muscle length, Oswestry disability index and visual analogue scale in experimental and control group. Conclusion: Pain was improved using dry needling. However, no significant improvement was seen in patient's disability and lumbar paraspinal muscle length.
... MTrPs are identified through palpation and the identification of taut bands in the skeletal muscle (Unverzagt et al., 2015). These taut bands are composed of skeletal muscle and fascia and can cause localized tenderness and referred pain (Celik & Mutlu, 2013). The mechanism of action behind dry needling is unclear, but it is believed that it may elicit an analgesic effect, relax the actin-myosin bonds, and improve muscle blood flow in the area surrounding the tissues (Cagnie et al., 2013;Dunning et al., 2014;Kietrys et al., 2013;Unverzagt et al., 2015). ...
Article
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Introduction Dry needling has been identified as a potential intervention for a variety of diagnoses. Limited evidence exists to support the use of dry needling following surgical intervention of a distal radius fracture. This case report demonstrates the impact of dry needling in the thumb following a distal radius fracture. Methods The patient was a 31-year-old healthy female who sustained a distal radius fracture and required surgical intervention. The patient required a volar plate removal and extensor tenolysis. The patient attended traditional occupational therapy with one session of dry needling to assist in improving range of motion and decreasing pain. Results The patient benefited from the use of dry needling. The patient had no pain with functional grasping and pinching following dry needling and improved on the Kapandji score from eight to nine out of ten. The patient also reported a decrease in overall pain, from seven to two on the Numeric Pain Rating Scale. Discussion The patient benefited from dry needling in the thumb to improve both range of motion and pain symptoms. While the evidence is limited, dry needling may be an appropriate intervention to assist in recovery and reduce thumb pain following distal radius fractures.
Chapter
Myofascial pain is one of the most common forms of human pain and a major cause of disability. It is characterized by spontaneous muscle pain and pain induced by pressing the muscle’s trigger points. Treatment of myofascial pain syndrome (MPS) is partially successful with nonpharmacological measures and analgesic agents, but a large number of patients remain unsatisfied. Eleven double-blind, placebo-controlled studies have been published on treatment of myofascial pain with botulinum toxins; some of these studies strongly support the palliative role of botulinum neurotoxins (BoNTs) in myofascial pain syndrome. Successful studies that have used onabotulinumtoxinA and abobutulinumtoxinA for this form of pain emphasize the importance of a flexible rather than a fixed pattern of injection and injecting more than five or all trigger points. Fibromyalgia is a systemic disease, characterized by diffuse muscle pain, fatigue, headaches, mood disorders, sleep disturbance, bowel disorders, and endocrine dysfunction. Due to lack of controlled data, the use of BoNTs for treatment of fibromyalgia is not currently recommended.
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Introduction Myofascial pain syndrome (MPS) is one of the most common disorders causing chronic muscle pain. Almost one-third of patients with musculoskeletal complaints meet the MPS criteria. The aim of this study is to evaluate the effectiveness of intramuscular electrical stimulation (IMES) in patients with MPS through a systematic review method. Methods PubMed, Scopus, Embase, ProQuest, PEDro, Web of Science, and CINAHL were systematically searched to find out the eligible articles without language limitations from 1990 to December 30, 2020. All relevant randomized controlled trials that compared the effectiveness of IMES with sham-IMES, dry needling, or exercise therapy in patients with MPS were included. Full texts of the selected studies were critically appraised using Revised Cochrane risk-of-bias tool for randomized trials (RoB2). Results Six studies (out of 397) had met our inclusion criteria (involving 158 patients) and were entered to the systematic review. Outcome measures examined in these studies included pain, range of motion, pressure pain threshold, biochemical factors, disability, and amount of analgesic use. In the most studies, it has been shown that IMES is more effective than the control group in improving some outcome measurements such as pain. Conclusion There is preliminary evidence from a few small trials suggesting the efficacy of IMES for the care of myofascial pain syndrome. The data support the conduct of larger trials investigating the efficacy of IMES.
Article
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Theories regarding the molecular pathophysiology of myofascial trigger points (MFTrPs) have undergone fundamental revisions in recent years. New research suggests that MFTrPs are evoked by the abnormal depolarization of motor end plates. The motor endplate transduces electrical potential into muscle contraction. This review article expands the proposed etiology to include presynaptic, synaptic, and postsynaptic mechanisms, such as excessive release of acetycholine (ACh), defects of acetylcholinesterase, and upregulation of nicotinic ACh receptors, respectively. Dysfunctional motor endplates and sustained muscular contraction give rise to a localized "ATP energy crisis" associated with sensory and autonomic reflex arcs that is sustained by central sensitization. This working hypothesis has given rise to several new approaches in the treatment of MFTrPs.
Article
Introduction Sustained manual pressure has been advocated as an effective treatment for myofascial trigger points (MTrPs).1, 2 and 3 This study aimed to investigate the effect of manual pressure release (MPR) on the pressure sensitivity of latent MTrPs in the upper trapezius muscle, using a novel pressure algometer. Design Randomised blinded clinical trial. Methods Participants: Thirty-seven subjects (mean age 23.1 years ± 3.2; M = 12, F = 23) were screened for the presence of latent MTrPs in the upper trapezius muscle (tender band that produced referred pain to the neck and/or head on manual pressure). Intervention: Subjects were randomly allocated into either treatment (MPR pressure sustained for 60 s) or control (sham myofascial release) group. Outcome Measures: The pressure pain threshold (PPT) was recorded pre- and post-intervention using a digital algometer, consisting of a capacitance sensor attached to the tip of the palpating thumb. Changes in pressure sensitivity were also measured during the application of MPR via a verbal analogue pain scale (0–10, 0 = no pain, 10 = severe pain). Results There was a significant increase in mean PPT following MPR (P < 0.001), but not following the sham treatment. Pressure was monitored and maintained during the application of MPR, and a reduction in perceived pain and significant increase in tolerance to treatment pressure (P < 0.001) appeared to be caused by a change in tissue sensitivity, rather than an unintentional reduction of pressure by the examiner. Conclusions The results suggest that MPR may be an effective therapy for MTrPs in the upper trapezius muscle.
Article
The aim of this pilot study was to compare the effects of a single treatment of the ischemic compression technique with transverse friction massage for myofascial trigger point (MTrP) tenderness. Forty subjects, 17 men and 23 women, aged 19–38 years old, presenting with mechanical neck pain and diagnosed with MTrPs in the upper trapezius muscle, according to the diagnostic criteria described by Simons and by Gerwin, participated in this pilot study. Subjects were divided randomly into two groups: group A which was treated with the ischemic compression technique, and group B which was treated with a transverse friction massage. The outcome measures were the pressure pain threshold (PPT) in the MTrP, and a visual analogue scale assessing local pain evoked by a second application of 2.5 kg/cm2 of pressure on the MTrP. These outcomes were assessed pre-treatment and 2 min post-treatment by an assessor blinded to the treatment allocation of the subject. The results showed a significant improvement in the PPT (P=0.03P=0.03), and a significant decrease in the visual analogue scores (P=0.04P=0.04) within each group. No differences were found between the improvement in both groups (P=0.4P=0.4). Ischemic compression technique and transverse friction massage were equally effective in reducing tenderness in MTrPs.
Article
The aim of this study was to compare the immediate effect, on active mouth opening, following a single treatment of latent myofascial trigger points (MTrPs) in the masseter muscle involving a muscle energy technique, i.e. post-isometric relaxation, and the strain/counterstrain technique. Ninety subjects, 42 men and 48 women, aged 19–44 years old, participated in this study. Subjects underwent a screening process to establish the presence of MTrPs in the masseter muscle as described by Simons et al. Subjects were divided randomly into three groups: group A which was treated with a post-isometric relaxation technique, group B treated with the strain/counterstrain technique, and group C as control group. The outcome measure was the maximum active mouth opening. It was assessed pre-treatment and 5min post-treatment by an assessor blinded to the treatment allocation of the subject. Within-group changes showed a significant improvement in active mouth opening following application of the post-isometric relaxation technique (P0.001), but not following application of strain/counterstrain (P=0.08). The control group did not show any change (P0.1). Pre–post-effect sizes were large in the post-isometric relaxation group (d=1.46), small to medium in the strain/counterstrain group (d=0.32) and small in the control group (d=0.01). Differences were found between the post-isometric relaxation group and both the strain/counterstrain and control groups (P0.001), but not between these two latter groups (P=0.8). Our results suggest that the post-isometric relaxation technique might be employed in the management of latent MTrPs in the masseter muscle in order to improve the maximum mouth opening.
Article
Objectives: To study the immediate effectiveness of treatment on an active myofascial trigger point with physical medicine modalities, including spray and stretch, hydrocollator superficial heat, ultrasound deep heat, and deep pressure soft tissue massage. Methods: Eighty-four patients with myofascial pain syndrome and 24 normal subjects were studied. Pain threshold of the active pressure algometer [Pressure Threshold Meter] before and after the treatment with each one of the above mentioned modalities and placebo "sham ultrasound." The Index of Threshold Change [ITC] is defined as the ratio of post-treatment pain threshold to pre-treatment pain threshold. Results: In the control study, the normal subjects without any treatment had an average ITC value of 1.02 ± 0.06 based upon 48 measurements; the patients without any treatment had an average ITC value of 1.02 ± 0.07 [n = 21], and the patients treated with placebo had an average ITC value of 1.09 ± 0.18 [n = 16]. The average ITC values were 1.53 ± 0.32 [n = 17] from hydrocollator treatment; 1.41 ± 0.39 [n = 16] from ultrasound therapy; and 1.77 ± 0.40 [n = 16] from deep pressure massage therapy. The ITC value from treatment with any of the 4 modalities was significantly higher than the ITC of any of the 3 control groups [P < 0.05, 2-tailed ANOVA], however, there were no significant differences among the other 3 modalities. The ITC value from treatment with stretchtherapy [spray and stretch or massage, n = 35] was significant higher than [P < 0.05, 2-tailed ANOVA] that with thermotherapy [hydrocollator or ultrasound, n = 33]. Conclusion: It would appear that all 4 therapeutic modalities can be effectively applied for the treatment of myofascial pain syndrome to obtain an immediate increase of pain threshold of an active myofascial trigger point, although the stretch therapy is more effective than the thermotherapy.
Article
Purpose The aim of this study was to compare the immediate effect, on pain threshold, following a single treatment of tender points in the upper trapezius muscle involving a classical and a modified application of the strain/counterstrain technique. Methods Fifty-four subjects presenting with mechanical neck pain, 16 men and 38 women, aged 18–64 years old, participated in this study. Subjects underwent a screening process to establish the presence of tender points in the upper trapezius muscle. Subjects were divided randomly into three groups: group A was treated with the classical strain/counterstrain technique, group B was treated with the modified application of the technique which included a longitudinal stroke during the application of strain/counterstrain, and group C was a control group. The outcome measure was the visual analogue scale assessing local pain elicited by the application of 4.5 kg/cm2 of pressure on the tender point. It was assessed pre-treatment and 2 min post-treatment by an assessor blinded to the treatment allocation of the subject. Results Within-group changes showed a significant improvement in the visual analogue scale following either classical or modified application of the strain/counterstrain technique (P < 0.001). The control group did not show any change (P > 0.3). Pre-post effect sizes were large in both strain/counterstrain groups (D = 1.1), but small in the control group (D = 0.01). Differences were found between both strain/counterstrain groups as compared to the control group (P < 0.001), but not between both strain/counterstrain groups (P = 0.8). Conclusions Our results suggest that strain/counterstrain was effective in reducing tenderness of tender points in the upper trapezius muscle. The application of a longitudinal stroke during the strain/counterstrain did not influence the effectiveness of the classical description of the technique.
Article
The core symptoms and signs of the fibromyalgia [FM] syndrome are generalized chronic pain occurring mainly in muscles and hyperalgesia [tender point]. There is not one single cause to FM. The pathogeneses is a chain of events. Some links in the chain are still missing and some links are weak. The hypothesis presented is that FM is caused by a combination of peripheral factors mainly muscle and central factors. The central factors result in a decrease of pain inhibition. © 1993 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.