Quantification of dry needling and posture effects on myofascial trigger points using ultrasound shear-wave elastography

Comparison of Dry Needling and Cold-Spray-Stretching Treatments by Ultrasonography and Electrophysiology: Prospective, Randomized Controlled Trial

OBJECTIVES

To compare the efficacy of dry needling (DN) and cold-spray-stretching treatments using surface electromyography (sEMG) and ultrasound (US) in the treatment of patients with myofascial pain syndrome (MPS) with active trigger point (ATrP) in the upper trapezius muscle.

METHODS

This prospective randomized single-blind study included 60 MPS patients aged 18-65 years who have ATrP in the upper trapezius muscle. Patients were randomized into two treatment groups as DN and cold spray stretching. Both treatment groups received 1 treatment per week and totally 3 sessions. Evaluation parameters were pain level assessed by Numeric Rating Scale and algometer, neck range of motion angles, neck disability index (NDI). The effects of the treatments on ATrP were evaluated by sEMG and US histogram. All parameters were evaluated at the beginning of the treatment and at the end. Algometer and sEMG were performed also before and after the first and third sessions.

RESULTS

There was no significant difference between the two groups regarding demographic data. The mean age of the participants was 39.7 ± 11.6 years. Fifty-one patients were female. Significant improvement in terms of pain level, functionality, sEMG, and US histogram were achieved in both groups (P < .05). When comparing the two groups, algometer scores and the NDI score were statistically higher in the cold-spray-stretching group than in the DN group (P < .008 and P < .028, respectively).

CONCLUSION

Both treatment options should be preferred. The efficacy of both treatments was observed via sEMG and US histograms.

Using ultrasound elastography to assess non-invasive, non-pharmacological interventions for musculoskeletal stiffness: a systematic review and meta-analysis

PURPOSE

To evaluate the current evidence regarding the use of ultrasound elastography for assessing non-invasive, non-pharmacological interventions for eliciting changes in musculoskeletal stiffness.

METHODS

A systematic search of MEDLINE, CINAHL, EMBASE, and Web of Science databases was performed in accordance with Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Information on measurement and intervention procedures was extracted. Bias was assessed using Cochrane Risk of Bias or Risk of Bias In Non-randomised Studies of Interventions (ROBINS-I) tools for studies with true or quasi-experimental designs, respectively. Analyses were conducted for adequately powered subgroups based on intervention type, measurement site, and population assessed.

RESULTS

Twenty-one studies were included in the review. Overall risk of bias was low for true experimental studies and moderate for quasi-experimental studies. Subgroup analyses indicated a large overall effect for interventions involving manual physiotherapy and taping/splinting for reducing masseter muscle stiffness in patients with masticatory muscle disorders (g = 1.488, 95% CI = 0.320-2.655, p = 0.013). Analyses for other intervention types and patient groups were underpowered.

CONCLUSION

Ultrasound elastography demonstrates clinical applicability for assessing non-invasive, non-pharmacological interventions for musculoskeletal stiffness. However, the comparative efficacy of these interventions for modulating tissue stiffness remains inconclusive.

The Invasive Management of Pain: Diagnosis and New Treatment Options

Both the diagnosis and treatment of pain are evolving, especially in interventional approaches. Diagnosis of low back pain combines old and new methodologies, in particular, it involves an expanded role for ultrasound. While low back pain is a common complaint, there are many etiologies to the condition which must be explored before a final diagnosis can be made and treatment planned. Tumors and infections are rarely involved in low back pain but should be ruled out in the initial phase itself since failing to address them early can have devastating consequences. Some invasive treatments seem promising in the management of low back pain. Treating musculoskeletal pain with regenerative medicine, such as platelet-rich plasma, holds great promise. Autologous blood products are safe and may help stimulate the body's own responses for regeneration. The so-called "orthobiologics" play a role in sports medicine and the treatment of musculoskeletal pain. Neuromodulation, especially spinal cord stimulation, is undergoing a renaissance with new waveforms, devices, and a greater albeit incomplete understanding of its mechanisms of action. Spinal cord stimulation is not a first-line therapy and not all patients or all back problems respond to this treatment. Nevertheless, the therapy can be safe, effective, and cost-effective with appropriate patient selection. Radiofrequency ablation of nerves in the form of neurotomy can be effective in reducing the pain of osteoarthritis. These procedures, including the newer cooled radiofrequency neurotomy, can restore function, reduce pain, and may potentially have an opioid-sparing effect. Technical expertise in nerve and anatomy is needed for the use of this technique. This review article aims to provide updated information on some invasive intervention techniques in pain management.

Suggesting a mechanism for acupuncture as a global percutaneous needle fasciotomy that respects tensegrity principles for treating fibromyalgia

Acupuncture is a minimally invasive therapeutic method that uses small caliber needles while inserting them through the skin into various areas of the body. Some empirical studies find evidence to support the use of acupuncture as a treatment for certain medical conditions, however, this peculiar practice is widely considered as the domain of alternative and non-evidence-based medicine. Several mechanisms have been suggested in an attempt to explain the therapeutic action of acupuncture, but the way in which acupuncture alleviates chronic non-cancer pain or psychosomatic and psychiatric disorders is not fully understood. A recent study suggested a theoretical model (coined "Fascial Armoring") with a cellular pathway to help explain the pathogenesis of myofascial pain/fibromyalgia syndrome and functional psychosomatic syndromes. It proposes that these syndromes are a spectrum of a single medical entity that involves myofibroblasts with contractile activity in fascia and aberrant extracellular matrix (ECM) remodeling, which may lead to widespread mechanical tension and compression. This can help explain diverse psycho-somatic manifestations of fibromyalgia-like syndromes. Fascia is a continuous interconnected tissue network that extends throughout the body and has qualities of bio-tensegrity. Previous studies show that a mechanical action by needling induces soft tissue changes and lowers the shear modulus and stiffness in myofascial tissue. This hypothesis and theory paper offers a new mechanism for acupuncture therapy as a global percutaneous needle fasciotomy that respects tensegrity principles (tensegrity-based needling), in light of the theoretical model of "Fascial Armoring." The translation of this model to other medical conditions carries potential to advance therapies. These days opioid overuse and over-prescription are ubiquitous, as well as chronic pain and suffering.

Validation of shear wave elastography as a noninvasive measure of pelvic floor muscle stiffness

OBJECTIVES

To investigate the validity of shear wave elastography (SWE) as a measure of stiffness of the puborectalis muscle by examining: (1) the relationship between puborectalis muscle stiffness and pelvic floor muscle (PFM) activation at different intensities; and (2) the relationship between puborectalis stiffness and pelvic floor morphometry during contractions at different intensities.

METHODS

Fifteen healthy asymptomatic women performed 6-s isometric PFM contractions at different intensities (0, 10%, 20%, 30%, 50%, 75%, and 100% of maximal voluntary contraction) guided by intravaginal electromyography (EMG). Stiffness of the puborectalis muscle was measured using SWE by calculating the average shear modulus in regions of interest that contained puborectalis muscle fibers parallel to the transducer. Pelvic floor morphometry was assessed in the mid-sagittal plane using transperineal B-mode ultrasound imaging. Shear modulus, EMG (root mean square amplitude) and pelvic floor morphometry parameters were normalized to the value recorded during maximal voluntary contraction. To assess the relationship between stiffness and pelvic floor activation/morphometry, coefficient of determination (r² ) was calculated for each participant and a group average was computed.

RESULTS

Shear modulus and EMG were highly correlated (average r² ; left 0.90 ± 0.08, right 0.87 ± 0.15). Shear modulus also strongly correlated with bladder neck position (x-axis horizontal coordinates relative to the pubic symphysis), anorectal rectal angle and position, levator plate angle, and antero-posterior diameter of the levator hiatus (average r² : range 0.62-0.78).

CONCLUSIONS

These findings support the validity of SWE to assess puborectalis muscle stiffness in females. Stiffness measures were strongly associated with PFM EMG and pelvic floor morphometry and may be used to indirectly assess the level of activation of the puborectalis muscle without the use of more invasive techniques. By overcoming limitations of current assessment tools, this promising noninvasive and real-time technique could enable important breakthrough in the pathophysiology and management of pelvic floor disorders.

Changes in stiffness at active myofascial trigger points of the upper trapezius after dry needling in patients with chronic neck pain: a randomized controlled trial

BACKGROUND/OBJECTIVE

Since, to our knowledge, the effects of dry needling (DN) on active myofascial trigger point (MTrP) stiffness have not been analyzed previously with shear wave elastography (SWE), our aim was to compare the effects of a single session of DN and sham DN applied to the most active MTrP located in the upper trapezius muscle on clinical outcomes.

METHODS

A randomized, double-blinded sham-controlled trial was conducted; 60 patients were randomized into an experimental (DN) or sham (sham DN) group. Baseline data including sociodemographic and clinical characteristics were collected. SWE and pain pressure thresholds (PPTs) at the MTrP and a control point located 3 cm laterally were the main outcomes assessed before and 10 min after the interventions.

RESULTS

Patients receiving DN interventions experienced greater increases in the control point PPTs immediately after receiving the intervention compared with sham DN (p < 0.05), but no differences were found for the MTrP (p > 0.05). Post-intervention PPT improvements were found at both locations for both groups (p < 0.01). No significant changes for either MTrP or control locations were found for SWE outcomes in either group (all ps > 0.05). No significant within-group SWE differences were found in the DN or sham DN groups (p > 0.05).

CONCLUSION

A single session of DN or sham DN applied to active MTrPs located in the upper trapezius muscle produced no detectable changes in stiffness at the MTrP or control locations. Real DN induced an immediate analgesic response at both MTrP and control locations, while sham DN induced an immediate MTrP response.

TRIAL REGISTRATION NUMBER

NCT04832074 (ClinicalTrials.gov).

Immediate Effect of Dry Needling on the Viscoelastic Properties of a Trigger Point on the Infraspinatus Muscle Measured with MyotonPRO

Purpose: This article investigates the immediate effects of a dry needling (DN) puncture on the viscoelastic properties (tone, stiffness, elasticity) of a trigger point (TP) in the infraspinatus muscle in non-traumatic chronic shoulder pain. Method: Forty-eight individuals with non-traumatic chronic shoulder pain were recruited. The presence of a TP in the infraspinatus muscle was confirmed by a standardized palpatory exam. The viscoelastic properties were measured with a MyotonPRO device at baseline (T1), immediately after DN (T2), and 30 minutes later (T3). A DN puncture was applied to the TP to obtain a local twitch response while performing the technique. Results: Analyses of variance showed significant decreases in tone ( p < 0.001) and stiffness ( p = 0.003) across time after the DN technique. Post hoc tests revealed a significant reduction in tone and stiffness from T1 to T2 ( p ≤ 0.004) and no significant changes from T2 to T3 ( p ≥ 0.10). At T3, only stiffness remained significantly lower compared to T1 ( p = 0.013). Conclusions: This study brings new insights on the immediate mechanical effect of DN on tone and stiffness of TPs. Whether these effects are associated with symptom improvement and long-term effects still needs to be verified.

Scoping review and interpretation of myofascial pain/fibromyalgia syndrome: An attempt to assemble a medical puzzle

BACKGROUND

Myofascial Pain Syndrome (MPS) is a common, overlooked, and underdiagnosed condition and has significant burden. MPS is often dismissed by clinicians while patients remain in pain for years. MPS can evolve into fibromyalgia, however, effective treatments for both are lacking due to absence of a clear mechanism. Many studies focus on central sensitization. Therefore, the purpose of this scoping review is to systematically search cross-disciplinary empirical studies of MPS, focusing on mechanical aspects, and suggest an organic mechanism explaining how it might evolve into fibromyalgia. Hopefully, it will advance our understanding of this disease.

METHODS

Systematically searched multiple phrases in MEDLINE, EMBASE, COCHRANE, PEDro, and medRxiv, majority with no time limit. Inclusion/exclusion based on title and abstract, then full text inspection. Additional literature added on relevant side topics. Review follows PRISMA-ScR guidelines. PROSPERO yet to adapt registration for scoping reviews.

FINDINGS

799 records included. Fascia can adapt to various states by reversibly changing biomechanical and physical properties. Trigger points, tension, and pain are a hallmark of MPS. Myofibroblasts play a role in sustained myofascial tension. Tension can propagate in fascia, possibly supporting a tensegrity framework. Movement and mechanical interventions treat and prevent MPS, while living sedentarily predisposes to MPS and recurrence.

CONCLUSIONS

MPS can be seen as a pathological state of imbalance in a natural process; manifesting from the inherent properties of the fascia, triggered by a disrupted biomechanical interplay. MPS might evolve into fibromyalgia through deranged myofibroblasts in connective tissue ("fascial armoring"). Movement is an underemployed requisite in modern lifestyle. Lifestyle is linked to pain and suffering. The mechanism of needling is suggested to be more mechanical than currently thought. A "global percutaneous needle fasciotomy" that respects tensegrity principles may treat MPS/fibromyalgia more effectively. "Functional-somatic syndromes" can be seen as one entity (myofibroblast-generated-tensegrity-tension), sharing a common rheuma-psycho-neurological mechanism.

In Hamstring Muscles of Patients With Knee Osteoarthritis an Increased Ultrasound Shear Modulus Indicates a Permanently Elevated Muscle Tonus

Background

Some patients with knee osteoarthritis (KOA) show pain, stiffness and limited flexion and extension at the back of the knee, leading to dysfunction and affecting life. This may be related to changes in the biomechanical properties of skeletal muscles. Shear wave elastography (SWE) can detect these changes by measuring muscle shear modulus.

Aims

To investigate hamstring muscle shear modulus of healthy people and patients was studied using SWE method, and the correlation analysis between the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score of patients’ subjective feeling and shear modulus of objective quantification was conducted.

Methods

The hamstring shear modulus was measured by SWE in 50 patients and 50 healthy individuals. Pearson correlation coefficient was used to evaluate the correlation between hamstring stiffness and shear modulus in patients.

Results

The hamstring shear modulus were significantly higher in the KOA group [the semimembranosus (SM) 15.23 ± 7.23, the semitendinosus (ST) 15.94 ± 5.40, the biceps femoris long tendinitis (BFL) 14.21 ± 6.55] than in the control group (the SM 10.95 ± 2.41, the ST 11.25 ± 2.23, the BFL 9.98 ± 2.81) (p = 0.000, p = 0.000, p = 0.001). The hamstring shear modulus in the KOA group was moderately positively correlated with pain, shear modulus, and physical function score.

Conclusion

Preliminary results show that the shear modulus of the hamstring of KOA patients is higher than that of healthy people, the WOMAC score and the shear modulus of patients are moderately correlated. These preliminary results show that ultrasonic shear wave elastography measurement of shear modulus may be enough to sensitive, can detect these effects, more targeted in order to assist the doctor’s diagnosis and treatment.

Neck Disability Index Is Better in Classification of Recovery after Whiplash Injury in Comparison with Ultrasound Shear Wave Elastography of Trapezius Muscle

A prospective observational study comparing shear wave elastography (SWE) of trapezius muscle with Neck Disability Index (NDI) in a prediction model of health status six months after a whiplash injury. Both SWE values, measured by two radiologists, and NDI scores were obtained at baseline and after physical therapy (PT) (6-month period). Those values were compared with a 3-point Likert scale (no, partial or full recovery). Twenty-two subjects completed the study. A decrease in trapezius stiffness was detected by both radiologists, statistically significant for one (Δ10.1 kPa; p = 0.04) but not for the second radiologist (Δ8.63 kPa; p = 0.07). The measurements showed excellent intra-observer (ICC 0.75–0.94) and inter-observer (ICC 0.78–0.88) reliability. After six months, fully recovered patients showed lower NDI scores than partially recovered patients (Δ22.98; p < 0.001). SWE values did not differ with the recovery status (55.6 ± 9.7 vs. 57 ± 15.8, Δ1.45; p = 0.82). The single most accurate variable in classifying health status six months after whiplash injury was the relative change of NDI, and it showed the highest accuracy (73.9%) and low Akaike information criterion (AIC = 39.2). Overall, the most accurate classification was obtained when combining NDI and SWE after physical therapy with an accuracy of 77.3% and a decrease in AIC (32.8).

Quantitative Ultrasound Texture Feature Changes With Conservative Treatment of the Trapezius Muscle in Female Patients With Myofascial Pain Syndrome

OBJECTIVE

We set out to assess whether quantitative ultrasound could be used to assess changes that occur after physical therapy in patients experiencing myofascial pain syndrome.

METHODS

We consecutively recruited female subjects experiencing myofascial pain syndrome of the neck and shoulder region and provided 10 sessions of conservative physical therapy. A control group was recruited for textural analyses. We measured change in pain ratings, range of motion, and ultrasound texture features before and after the intervention and after 3 mos.

RESULTS

We recruited 63 female myofascial pain syndrome subjects and 20 healthy controls. After treatment, the mean blob size (an ultrasound texture feature) value for each subject decreased from 30.84 ± 5.00 to 25.86 ± 5.67 on the right and decreased from 31.70 ± 5.51 to 28.08 ± 5.53 on the left (P < 0.0005). The blob count showed a significant increase only on the left side (P < 0.01). Corresponding to this were reductions in pain and disability scores after treatment and at 3 mos compared with retreatment (P < 0.0005 for all checkpoints). Cervical range of motion values were significantly increased only at 3 mos compared with pretreatment except for mean flexion range of motion.

CONCLUSIONS

Ultrasound texture feature of blob size and count changes correspond to routine clinical outcomes after conservative physical therapy of myofascial pain syndrome in female individuals.

Assessment of Myofascial Trigger Points via Imaging: A Systematic Review

ABSTRACT

This study systematically reviewed the published literature on the objective characterization of myofascial pain syndrome and myofascial trigger points using imaging methods. PubMed, Embase, Ovid, and the Cochrane Library databases were used, whereas citation searching was conducted in Scopus. Citations were restricted to those published in English and in peer-reviewed journals between 2000 and 2021. Of 1762 abstracts screened, 69 articles underwent full-text review, and 33 were included. Imaging data assessing myofascial trigger points or myofascial pain syndrome were extracted, and important qualitative and quantitative information on general study methodologies, study populations, sample sizes, and myofascial trigger point/myofascial pain syndrome evaluation were tabulated. Methodological quality of eligible studies was assessed based on the Quality Assessment of Diagnostic Accuracy Studies criteria. Biomechanical properties and blood flow of active and latent myofascial trigger points assessed via imaging were found to be quantifiably distinct from those of healthy tissue. Although these studies show promise, more studies are needed. Future studies should focus on assessing diagnostic test accuracy and testing the reproducibility of results to establish the best performing methods. Increasing methodological consistency would further motivate implementing imaging methods in larger clinical studies. Considering the evidence on efficacy, cost, ease of use and time constraints, ultrasound-based methods are currently the imaging modalities of choice for myofascial pain syndrome/myofascial trigger point assessment.

Effect of dry needling on lumbar muscle stiffness in patients with low back pain: A double blind, randomized controlled trial using shear wave elastography

Background: Dry needling treatment focuses on restoring normal muscle function in patients with musculoskeletal pain; however, little research has investigated this assertion. Shear wave elastography (SWE) allows quantification of individual muscle function by estimating both resting and contracted muscle stiffness.Objective: To compare the effects of dry needling to sham dry needling on lumbar muscle stiffness in individuals with low back pain (LBP) using SWE.Methods: Sixty participants with LBP were randomly allocated to receive one session of dry needling or sham dry needling treatment to the lumbar multifidus and erector spinae muscles on the most painful side and spinal level. Stiffness (shear modulus) of the lumbar multifidus and erector spinae muscles was assessed using SWE at rest and during submaximal contraction before treatment, immediately after treatment, and 1 week later. Treatment effects were estimated using linear mixed models.Results: After 1 week, resting erector spinae muscle stiffness was lower in individuals who received dry needling than those that received sham dry needling. All other between-groups differences in muscle stiffness were similar, but non-significant.Conclusion: Dry needling appears to reduce resting erector spinae muscle following treatment of patients with LBP. Therefore, providers should consider the use of dry needling when patients exhibit aberrant stiffness of the lumbar muscles.

Effects of Dry Needling on Biomechanical Properties of the Myofascial Trigger Points Measured by Myotonometry: A Randomized Controlled Trial

OBJECTIVE

The purpose of the present study was to examine the effect of dry needling (DN) on the biomechanical properties of a latent medial myofascial trigger point (MTrP) of the soleus muscle compared with an adjacent point within the taut band (TB) measured by myotonometry.

METHODS

Fifty asymptomatic volunteers were randomly assigned to an intervention group (n = 26) or control group (n = 24). One session of DN was performed in every group as follows: 10 needle insertions into the MTrP area (intervention group) or TB area (control group). Myotonometric measurements (frequency, decrement, and stiffness) were performed at baseline (pre-intervention) and after the intervention (post-intervention) in both locations (MTrP and TB areas).

RESULTS

The results showed that stiffness outcome significantly decreased with a large effect size after DN in the MTrP when measured in the MTrP location (P = .002; d = 0.928) but not when measured in the TB location. In contrast, no significant changes were observed in any location when the TB was needled (P > .05).

CONCLUSIONS

The findings suggest that only DN into the MTrP area was effective in decreasing stiffness outcome, therefore a specific puncture was needed to modify myofascial muscle stiffness.

The effect of dry needling of myofascial trigger points on muscle stiffness and motoneuron excitability in healthy subjects

BACKGROUND

Myofascial trigger points (MTrPs) are hypersensitive nodules in a taut band (TB) of skeletal muscle. Dry needling (DN) is an invasive technique recommended for the treatment of MTrPs. However, to our knowledge, no studies have investigated the influence of the DN technique on modification of muscle stiffness and neurophysiological properties of MTrPs.

OBJECTIVE

The objective was to examine the effect of DN on muscle stiffness and motoneuron excitability of a latent medial MTrP (nodule and TB) of the soleus muscle in non-injured subjects.

METHODS

A double-blinded randomised controlled trial of 46 subjects with latent medial MTrPs of the soleus was conducted, in which all received one session of DN. The intervention group (n = 23) were subjected to DN into the MTrP (the nodule), while the control group (n = 23) were subjected to DN into the TB. Assessment was carried out at baseline (pre-test), after the intervention (post-test) and 1 week after the intervention (follow-up). Biomechanical variables (muscle resistive force at 10°/s and 180°/s, muscle extensibility and strength), as measured with an isokinetic dynamometer, and neurophysiological variables (H-reflex), were recorded.

RESULTS

There were no statistically significant differences in biomechanical or neurophysiological assessments between groups. Considering the intra-group analysis, subjects in the intervention group exhibited increased maximal isometric voluntary force to ankle plantarflexion (MIVF_p) at both post-intervention and follow-up assessment (p < 0.0125; 0.2 < d < 0.5), while no changes were found in the control group.

CONCLUSION

One session of DN targeting latent MTrPs did not change muscle stiffness, muscle extensibility or motoneuron excitability. Further research on subjects with muscle tone disorders should be considered to better address the impact of DN on muscle tone.

TRIAL REGISTRATION NUMBER

NCT02575586 (ClinicalTrials.gov).

Is Shear-Wave Elastography a Clinical Severity Indicator of Myofascial Pain Syndrome? An Observational Study

Since manual palpation is a subjective procedure for identifying and differentiate Myofascial Trigger Points -MTrPs-, the use of Shear Wave Elastography -SWE- as an objective alternative is increasing. This study aimed to analyze pain pressure thresholds -PPTs- and SWE differences between active MTrPs, latent MTrPs and control points located in the upper trapezius to analyze the association of SWE features with clinical severity indicators (e.g., pain extension area, PPTs, neck pain and neck disability). An observational study was conducted to calculate the correlation and to analyze the differences of sociodemographic, clinical and SWE features on 34 asymptomatic subjects with latent MTrPs and 19 patients with neck pain and active MTrPs. Significant PPT differences between active with latent MTrPs (p < 0.001) and control points (p < 0.001) were found, but no differences between latent MTrPs and control points (p > 0.05). No stiffness differences were found between active MTrPs with latent MTrPs or control points (p > 0.05). However, significant control point stiffness differences between-samples were found (p < 0.05). SWE showed no significant correlation with clinical severity indicators (p > 0.05). No stiffness differences between active and latent MTrPs were found. Neck pain patients showed increased control point stiffness compared with asymptomatic subjects. SWE showed no association with clinical severity indicators.

Immediate decrease of muscle biomechanical stiffness following dry needling in asymptomatic participants

BACKGROUND

Biomechanical muscle stiffness has been linked to musculoskeletal disorders. Assessing changes in muscle stiffness following DN may help elucidate a physiologic mechanism of DN. This study characterizes the effects of dry needling (DN) to the infraspinatus, erector spinae, and gastrocnemius muscles on biomechanical muscle stiffness.

METHOD

60 healthy participants were randomized into infraspinatus, erector spinae, or gastrocnemius groups. One session of DN was applied to the muscle in standardized location. Stiffness was assessed using a MyotonPRO at baseline, immediately post DN, and 24 h later. The presence of a localized twitch response (LTR) during DN was used to subgroup participants.

RESULTS

A statistically significant decrease in stiffness was observed in the gastrocnemius, the LTR gastrocnemius, and the LTR erector spinae group immediately following DN treatment. However, stiffness increased after 24 h. No significant change was found in the infraspinatus group.

CONCLUSIONS

DN may cause an immediate, yet transitory change in local muscle stiffness. It is unknown whether these effects are present in a symptomatic population or related to improvements in clinical outcomes. Future studies are necessary to determine if a decrease in biomechanical stiffness is related to improvement in symptomatic individuals.

Effects of Dry Needling on Muscle Stiffness in Latent Myofascial Trigger Points: A Randomized Controlled Trial

The aim of this study was to analyze the effects of dry needling (DN) in upper trapezius latent trigger points (LTrPs) on muscle stiffness. A total of 51 recreational physically active subjects with LTrPs in the upper trapezius volunteered to participate and were randomly divided into a DN-group (n = 27) and a sham-DN group (n = 24). Volunteers received 1-session of DN or placebo treatment. Muscle stiffness, measured with strain and shear-wave elastography, pressure pain threshold (PPT), post-needling soreness, and muscle thickness were evaluated before treatment, and at 30-min, 24-hours, and 72-hours follow-up after treatment. The DN-group showed lower values from baseline for muscle stiffness measured with shear-wave elastrography at 24-hours (from 44.44 ± 15.97 to 35.78 ± 11.65 kpa; P < .01) and at 72-hours (35.04 ± 12.61 kpa; P < .01) and with strain elastography at 72-hours (from 1.75 ± 0.50 to 1.36 ± 0.40 AU; P < .01). The DN-group showed higher values of PPT than the sham-DN group at 72-hours (4.23 ± 0.75 vs. 5.19 ± 1.16 kg/cm²; P < .05). There was a progressive decrease in post-needling soreness compared to pain during needling of 33.13 ± 21.31% at 30-min, 80.92 ± 10.06% at 24-hours, and a total decrease in post-needling soreness in all participants at 72-hours. DN therapy is effective in reducing short-term muscle stiffness and increasing the PPT in volunteers with LTrPs in the upper trapezius after a treatment session. PERSPECTIVE: This study found that one session of DN intervention in latent trigger points of the upper trapezius muscle reduced muscle stiffness and the pressure pain threshold for the dry needling group compared to the sham dry needling group.

Paravertebral Muscle Mechanical Properties and Spinal Range of Motion in Patients with Acute Neck or Low Back Pain: A Case-Control Study

Our aims were to identify potential differences in muscle mechanical properties (MMPs) of cervical and lumbar tissues and in spinal range of motion (ROM) between patients with acute low back pain (LBP) or acute neck pain (NP) and healthy controls, and to identify if ROMs and MMPs are able to identify subjects among the three groups. Clinical variables (pain, disability, fear of movement, kinesiophobia, quality of life), MMPs and ROMs were obtained in 33 subjects with acute LBP, 33 with acute NP, and 33 healthy control subjects. Between-groups differences and explanatory models to discriminate groups depending on MMPs and ROMs were calculated. The results showed that cervical tone was higher in patients with acute NP than in controls, while cervical decrement was higher in both spinal pain groups. Patients with acute NP showed reduced cervical flexion when compared to acute LBP and control groups, and also cervical rotation, but just against controls. Furthermore, lumbar flexion was reduced in patients with acute LBP when compared to those with acute NP. Cervical decrement was able to discriminate spinal pain individuals from controls in a multinominal regression (R²: Cox–Snell estimation = 0.533; Nagelkerke estimation = 0.600). Lumbar flexion differentiated patients with acute LBP and controls, whereas cervical flexion differentiated patients with acute NP and controls. This study supports a tendency of the affectation of other spinal regions when only one is affected.

A comparison of visual analog scale and shear-wave ultrasound elastography data in fibromyalgia patients and the normal population

[Purpose] The aim of this study was to compare Visual Analog Scale (VAS) values with the Shear Wave Elastography (SWE) values of rhomboid major muscles in fibromyalgia (FM) patients with those of a normal healthy population. [Participants and Methods] Evaluation was made of 53 female patients diagnosed with FM according to the American Collage of Rheumatology criteria, and a control group of 47 healthy volunteers with a VAS score of 0. All the patients were applied with ultrasonography. The severity of pain was measured using a VAS. [Results] Mean age was calculated as 39 years (range, 23–60 years) in the patient group and 37 years (range, 21–58 years) in the control group. The mean SWE value of the rhomboid major muscle of the patients was 4.74 m/sn and 70.21 kPa on the right side and 4.46 m/sn and 58.78 kPa on the left side. In the control group, these values were 4.18m/sn and 55.03 kPa on the right side and 3.78 m/sn and 44.21 kPa on the left side. The mean VAS score of the patients was 7.3. [Conclusion] The use of SWE values could be more objective than the subjective parameter of the VAS score in the evaluation of the severity of pain in fibromyalgia.

A sonographic comparison of the effect of dry needling and ischemic compression on the active trigger point of the sternocleidomastoid muscle associated with cervicogenic headache: A randomized trial

BACKGROUND

Cervicogenic headache (CeH) is among the common types of headache which has an undesirable influence on the quality of life. The myofascial trigger point (MTrP) within the sternocleidomastoid (SCM) muscle is one of the most important causes of CeH.

OBJECTIVE

The purpose of this study was to compare the effect of dry needling (DN) and ischemic compression (IC) on the headache symptoms as well as MTrP-related features in subjects with CeH originating from MTrPs of the SCM muscle using a sonographic method.

METHODS

A total of 29 female subjects aged 35.34 ± 12.19 on average with a clinical diagnosis of CeH originating from MTrP in the SCM muscle were randomly divided into the DN, IC, and control groups. Both DN and IC groups received 4 treatment sessions. Headache intensity, duration, frequency, MTrP elastic modulus, MTrP area, and pressure pain threshold (PPT) were assessed 2 weeks before and after treatments.

RESULTS

In both DN and IC groups, a significant improvement was found in the headache intensity, duration, frequency, PPT, and MTrP area (P< 0.05). No significant differences were observed between DN and IC (P> 0.05). Pearson correlation revealed a significant correlation between headache intensity and the MTrP elastic modulus (P< 0.05).

CONCLUSIONS

Both interventions could reduce headache symptoms, PPT, and MTrP area. Neither intervention was found to be superior to the other in short-term follow-up. IC may be preferred since it has fewer unwanted side effects compared to DN. Based on the data, it may be concluded that some MTrP biomechanical features such as stiffness may influence the produced headache symptoms.

Ultrasound shear wave elastography measurement of the deep posterior cervical muscles: Reliability and ability to differentiate between muscle contraction states

The deep posterior cervical muscles (DPCM), specifically the semispinalis cervicis and cervical multifidus, are often impaired in patients with neck disorders and have been assessed by several imaging techniques. Prior ultrasound shear wave elastography (SWE) imaging and reliability assessments of the DPCM were performed utilizing similar positioning as assessments for the more superficial cervical extensors. Our objectives were to describe an SWE imaging technique for the DPCM, establish intra-rater reliability of DPCM SWE, and compare DPCM shear modulus during rest and submaximal contraction in both prone and seated positions in individuals without spinal pain. In sixteen participants, the DPCM was located using B-mode ultrasound, then muscle shear modulus was assessed via SWE at both rest and with contraction against a 2-kg resistance applied at the C2 spinous process. Within-day intra-rater reliability was moderate to good (ICC = 0.70-0.88). The DPCM were stiffer during contraction than at rest in the prone position (p = 0.002), and at rest in sitting versus at rest in prone (p = 0.003). Further research is needed to assess DPCM-specific SWE in symptomatic individuals and compare DPCM shear modulus to electromyography across contraction intensities.

A comparison of dry needling and kinesiotaping therapies in myofascial pain syndrome: A randomized clinical study

Objectives

This study aims to compare the effectiveness of dry needling (DN) and kinesiotaping (KT) therapies on pain, quality of life, depression, and physical function in the treatment of myofascial pain syndrome (MPS).

Patients and methods

The study included a total of 60 patients (4 males, 56 females; mean age 31.2±9.8 years; range, 18 to 56 years) diagnosed with MPS between January 2014 and June 2014. The patients were randomly divided into two treatment groups: the DN group (n=30) and KT group (n=30). Both groups performed stretching and postural exercises. The scales used for measurements were the Visual Analog Scale (VAS) for pain, a pressure algometer for the pressure-pain threshold, the Short Form-36 (SF-36) for the quality of life, Beck Depression Inventory (BDI) for depression, and the Neck Pain and Disability Scale (NPDS) for physical function. The patients were evaluated by a single assessor three times: pre-treatment, at the end of the treatment, and two months after the treatment.

Results

Both DN and KT provided significant improvements for all baseline measurements (VAS, pressure pain threshold, all subscales of SF-36, BDI, and NPDS scores) at the end of the treatment and two months after the treatment (p<0.05). However, there was no significant difference between the groups in all measurements (p>0.05).

Conclusion

Kinesiotaping is as an effective method as DN in the treatment of MPS. It can be served as a non-invasive alternative to patients with needle phobia.

The effect of dry needling on gastrocnemius muscle stiffness and strength in participants with latent trigger points

Abnormal muscle stiffness is a potential complication after injury and identifying interventions that modify muscle stiffness may be useful to promote recovery. The purpose of this study was to identify the short-term effects of dry needling (DN) on resting and contracted gastrocnemius muscle stiffness and strength of the triceps surae in individuals with latent myofascial trigger points (MTrPs). In this randomized controlled trial, 52 individuals received two DN treatment sessions to latent MTrPs and 50 individuals received two sham needling sessions. Resting and contracted muscle stiffness were assessed both at the treatment site and a standardized central site in the medial gastrocnemius head immediately post-treatment and one week after the last session. There were significant group by time interactions for resting muscle stiffness at the site of the MTrP (p = .03), but not at the central site (p = .29). Post-needling between group comparison indicated that the DN group had significantly lower resting muscle stiffness at the site of the MTrP than the sham group after adjusting for baseline differences. There were no significant between group differences in contracted muscle stiffness or muscle strength. Identifying strategies that can reduce aberrant muscle stiffness may help to guide management of individuals with neuromuscular pain-related conditions. Level of evidence: Therapy, level 2.

Reliability of shoulder muscle stiffness measurement using strain ultrasound elastography and an acoustic coupler

PURPOSE

Abnormal increases in muscle tone can be caused by various musculoskeletal disorders. The objective of this study was to evaluate intratester and intertester reliabilities in measuring the stiffness of the shoulder muscles using strain ultrasound elastography (USE) and an acoustic coupler.

METHOD

Tissue stiffness was measured in the trapezius muscle and in the supraspinatus muscle of healthy young volunteers.

RESULTS

The mean strain ratios measured by two experienced shoulder surgeons were significantly higher in the trapezius muscle than in the supraspinatus muscle (P < 0.001). Intratester reliability was rated as moderate to substantial for the trapezius muscle and substantial for the supraspinatus muscle. Intertester reliability was substantial for both muscles, with an intraclass correlation coefficient (2,1) of 0.62 [95% confidence interval (CI) 0.28-0.82] for the trapezius muscle and 0.69 (95% CI 0.40-0.86) for the supraspinatus muscle.

CONCLUSIONS

We found substantial intratester and intertester reliabilities for the trapezius and supraspinatus muscles, suggesting that USE represents a promising modality for measuring the stiffness of shoulder muscles. However, the clinical application of this method will require the development of a device that can standardize the scanning technique to further increase the reliability.

Effects of dry needling of active trigger points in the scalene muscles in individuals with mechanical neck pain: a randomized clinical trial

OBJECTIVE

The aim of this study was to compare the effects of dry needling (DN) versus pressure release over scalene muscle trigger points (TrPs) on pain, related disability, and inspiratory vital capacity in individuals with neck pain.

METHODS

In this randomized, single-blind trial, 30 patients with mechanical neck pain and active TrPs in the scalene musculature were randomly allocated to trigger point dry needling (TrP-DN; n = 15) or pressure release (n = 15) groups. The DN group received a single session of DN of active TrPs in the anterior scalene muscles, and the pressure release group received a single session of TrP pressure release over the same muscle lasting 30 s. The primary outcome was pain intensity as assessed by a numerical pain rate scale (NPRS, 0-10). Secondary outcomes included disability (neck disability index, NDI) and inspiratory vital capacity. Outcomes were assessed at baseline and 1 day (immediately post), 1 week, and 1 month after the treatment session. Data were expressed as mean score difference (Δ) and standardized mean difference (SMD).

RESULTS

Patients receiving DN exhibited a greater decrease in pain intensity than those receiving TrP pressure release at 1 month (Δ 1.2 (95% CI-1.8, -0.6), p = 0.01), but not immediately (1 day) or 1 week after. Patients in the DN group exhibited a greater increase in inspiratory vital capacity at all follow-up time points (Δ 281 mm (95% CI 130, 432) immediately after, Δ 358 mm (95% CI 227, 489) 1 week after, and Δ 310 mm (95% CI 180, 440) 1 month after treatment) than those in the pressure release group (p = 0.006). Between-group effect sizes were large at all follow-up time points (1.1 > SMD > 1.3) in favor of DN.

CONCLUSION

This trial suggests that a single session of DN over active TrPs in the scalene muscles could be effective at reducing pain and increasing inspiratory vital capacity in individuals with mechanical neck pain. Future studies are needed to further confirm these results.

Feasibility of Ultrasound-Guided Trigger Point Injection in Patients with Myofascial Pain Syndrome

We compared the feasibility of ultrasound (US)-guided myofascial trigger point (MTrP) injection with that of a blind injection technique following the use of shear wave elastography (SWE) for the measurement of stiffness at the MTrPs in patients with trapezius myofascial pain syndrome (MPS). A total of 41 patients (n = 41) were randomized to either the trial group (n = 21, SWE combined with US-guided injection) or the control group (n = 20, SWE combined with blind injection). At baseline and four weeks, they were evaluated for the manual muscle test (MMT), the range of motion (ROM), pain visual analogue scale (VAS) scores, Shoulder Pain and Disability Index (SPADI) scores and Neck Disability Index (NDI) scores during the abduction, adduction, flexion, extension, external rotation and internal rotation of the shoulder joint. Differences in changes in pain VAS scores, NDI scores and SPADI scores at four weeks from baseline between the two groups reached statistical significance (p = 0.003, 0.012, and 0.018, respectively). US-guided MTrP injection is a more useful modality as compared with a blind injection in patients with MPS.

Randomized Trial on Comparison of the Efficacy of Extracorporeal Shock Wave Therapy and Dry Needling in Myofascial Trigger Points

OBJECTIVE

The aim of the study was to compare the efficacy of radial extracorporeal shock wave therapy and dry needling in the treatment of myofascial trigger points in the upper trapezius muscle.

DESIGN

A total of 65 patients with myofascial trigger points were randomly divided into extracorporeal shock wave therapy group (n = 32) and dry needling group (n = 33). Patients received 3 wks of treatment at 1-wk intervals (in both groups). Visual analog scale, pressure pain threshold, Neck Disability Index, and shear modulus were evaluated before treatment, immediately after the first therapy, 1 mo, and 3 mos after the completion of the third therapy.

RESULTS

Significant improvements of visual analog scale, pressure pain threshold, and Neck Disability Index scores were observed at all time points after treatment (P < 0.01) in both treatment groups. The shear modulus of myofascial trigger points was reduced in both dry needling group (P < 0.05) and extracorporeal shock wave therapy group (P < 0.01) immediately after the first treatment. Significant reductions in shear modulus were maintained up to 3-mo posttreatment in both groups (P < 0.01). There were no significant differences between the radial extracorporeal shock wave therapy group and dry needling group.

CONCLUSIONS

The extracorporeal shock wave therapy is as effective as dry needling for relieving pain, improving function, and reducing shear modulus for patients with myofascial trigger points after a series of three treatments.

Dry needling equilibration theory: A mechanistic explanation for enhancing sensorimotor function in individuals with chronic ankle instability

Patients with chronic ankle instability (CAI) experience a dynamic interplay between impaired mechanical structures and sensorimotor deficiencies that contribute to recurrent sprains and sensations of instability. Concomitantly, muscular trigger points (MTrPs) are known to occur following trauma, maximal or submaximal concentric contractions, and unaccustomed eccentric loads. Additionally, MTrPs are theorized to be exacerbated in low-load and repetitive strain activities. MTrPs located within a muscle are associated with altered motor control, reaction delay, and decreased strength, deficits also found among those with CAI. Dry needling (DN) is reported to improve muscle range of motion, motor control, and pain in a myriad of neuromusculoskeletal conditions by decreasing spontaneous electrical activity and stiffness of taut muscle bands while improving filament overlap. Building on evidence supporting neuromechanical decoupling in chronic ligamentous injury with what is known about the development of MTrPs, this paper proposes a centrally mediated mechanism for improved sensorimotor function following DN for individuals with CAI. Dry needling equilibration theory (DNET) states that proprioception is improved following DN in the lower extremity by changing the muscle's length-tension relationship and leveraging minor acute discomfort to improve muscle spindle afferent information via the gamma motor system. The application of DNET for individuals with CAI may provide a mechanistic explanation for improved descending cortical output, resulting in enhanced sensorimotor function.

Shear Wave Elastography of the Lumbar Multifidus Muscle in Patients With Unilateral Lumbar Disk Herniation

OBJECTIVES

To assess lumbar multifidus muscle stiffness in patients with unilateral lumbar disk herniation (LDH) causing nerve root compression using shear wave elastography (SWE).

METHODS

Thirty-three patients with unilateral subarticular LDH (L3-L4, L4-L5, and L5-S1) causing nerve root compression, diagnosed by magnetic resonance imaging, were enrolled in the study. Exclusion criteria were bilateral or multilevel LDH confirmed on magnetic resonance imaging, bilateral leg symptoms, and patients with a history of any spinal operation, malignancy, trauma, infection, spondylolisthesis, severe lateral recess stenosis, spinal canal stenosis, and substantial comorbidities. Two observers separately evaluated the multifidus muscle using SWE. Shear wave elastographic examinations of the muscle were performed slightly below the herniation using the spinous process of the vertebra as a landmark. The stiffness of the muscle between affected and normal sides was compared. Moreover, the correlation between the stiffness and duration of the symptoms and the correlation between the stiffness and severity of the nerve compression were also calculated.

RESULTS

The mean stiffness values of the multifidus muscle on the affected side (mean ± SD: observer 1, 14.08 ± 3.57 kPa; observer 2, 13.70 ± 4.05 kPa) were significantly lower compared to the contralateral side (observer 1, 18.81 ± 3.95 kPa; observer 2, 18.28 ± 4.12 kPa; P < .001). The muscle stiffness had a moderate negative correlation with the duration of the symptoms and the severity of the nerve compression (observer 1, r = -0.535; observer 2, r = -0.458; P < .001).

CONCLUSIONS

The multifidus muscle on the ipsilateral side of the LDH showed reduced stiffness values, and stiffness values were negatively correlated with the disease duration and severity of the nerve compression. Further studies might reveal the potential role of SWE of the multifidus muscle in determining clinical outcomes and assessing effectiveness treatment in patients with LDH.

Modulation in Elastic Properties of Upper Trapezius with Varying Neck Angle

Background

Neck and shoulder complaints caused by poor posture may influence upper trapezius stiffness. The relationship between the shear elastic modulus of the upper trapezius and cervical flexion angles is unknown. Therefore, it is essential to assess upper trapezius stiffness during cervical flexion. The objectives of this study were to (1) determine the intra- and interoperator reliabilities of evaluating upper trapezius stiffness and calculate the minimal detectable change (MDC); (2) examine the elastic modulus alterations of the upper trapezius during cervical flexion; and (3) explore the difference of upper trapezius stiffness between the dominant and nondominant sides.

Methods

Twenty healthy male participants were recruited in this study. The shear modulus of the upper trapezius was evaluated by two independent investigators using shear wave elastography (SWE) during cervical flexion at 0° and 50°.

Findings

The intraoperator (intraclass correlation coefficient (ICC) = 0.85–0.86) and interoperator (ICC = 0.94–0.98) reliabilities for measuring the shear elastic modulus of the upper trapezius during the cervical flexion ranged from good to excellent. An increase of 35.58% in upper trapezius stiffness was found at 0° to 50° of cervical flexion, and the MDC was 7.04 kPa. In addition, a significant difference was obtained in the elastic modulus of the upper trapezius muscle between the dominant and nondominant sides (P < 0.05).

Conclusions

Our findings revealed that SWE could quantify the elastic modulus of the upper trapezius and monitor its changes. Therefore, further studies are required to delineate the modulation in upper trapezius muscle stiffness among subjects with neck and shoulder pain.

Normative parameters and anthropometric variability of lumbar muscle stiffness using ultrasound shear-wave elastography

BACKGROUND

Quantifying stiffness of the lumbar spine musculature using shear-wave elastography (SWE) maybe beneficial in the diagnosis and treatment of non-specific low back pain (LBP). The primary purpose of this study was to establish normative parameter and variance estimates of lumbar spine muscle stiffness at rest and during submaximal contraction levels using SWE in healthy individuals. A second aim was to determine the relationship between lumbar spine muscle stiffness and a variety of demographic, anthropometric, and medical history variables.

METHODS

This cross-sectional study included stiffness measurements of the lumbar musculature in 120 asymptomatic individuals using ultrasound SWE. The lumbar erector spinae muscle was measured during rest only and lumbar multifidus muscle was measured during rest and during submaximal contraction using a prone contralateral arm lift. Statistical comparisons of shear modulus were made between sex (male vs. female) and muscle condition (erector spinae rest, lumbar multifidus rest, lumbar multifidus contracted) using 2 × 3 repeated measures analysis of variance (ANOVA). Univariate associations between shear modulus and age, sex, BMI, activity level, and history of back pain were assessed using correlation analysis.

FINDINGS

Shear modulus at rest was approximately 4 kPa for the erector spinae muscles and approximately 6 kPa for the lumbar multifidus muscles. Shear modulus substantially increased during contraction, and varied by sex, BMI, and self-reported activity level, with men and more active individuals generally having stiffer muscles.

INTERPRETATION

Variability in shear modulus of the lumbar musculature may be mediated through a combination of muscle size and contractile state, which is consistent with our findings of higher stiffness in the more postural lumbar multifidi muscles, during contraction, and in larger and more active individuals. These findings should inform and be accounted for in future comparative clinical studies.

Localization of Muscle Edema and Changes on Muscle Contractility After Dry Needling of Latent Trigger Points in the Gastrocnemius Muscle

In this article, we aimed to describe what happens in skeletal muscle after dry needling intervention using magnetic resonance imaging (to show if there is edema) and tensiomyography (to measure contractile properties). At the same time, we describe the relationship between pain, edema, and contractility. Our results suggest that in asymptomatic patients, the application of dry needling over latent trigger points produce intra-muscular edema, an increase in muscle stiffness and an improved muscle contraction time.

Scanning electron microscopy examination of needle tips after different procedures of deep dry needling in humans

The aim of this study was to evaluate the tips and the surface conditions of two types of needles with different quality and their possible alterations after performing different needling on human beings. A total of 160 needles from AguPunt brand were examined. Surface conditions (lumps and scratches) and tip of the needles after needling procedures in humans were tested using a JEOL JSM-6360LV microscopy device. Additionally, a group of physiotherapists assessed the use of both types of needles in clinical practice using a self-reported questionnaire. Both types of needles, after performing different needling on human beings, kept the needle tips well preserved although the dry needle (Type B) suffered very little deformation even touching the bone of the scapula 10 times versus acupuncture needle (Type A), which were deformed slightly. The surface conditions revealed irregularities and scratches in both types of needles but the tips of Type A suffered more damage after different procedures (Odds ratio = 0.04,95% CI:0.01-0.13, p < 0.001). The cellular tissue adhered to the surface was similar in both types of needles and the questionnaire about clinical practice of both types of needles showed that Type B seemed easier than Type A when the physical therapist penetrated the skin and when the needle went out the skin.

Changes in Muscle Stiffness of the Trapezius Muscle After Application of Ischemic Compression into Myofascial Trigger Points in Professional Basketball Players

The study aimed to assess the effects of compression trigger point therapy on the stiffness of the trapezius muscle in professional basketball players (Part A), and the reliability of the MyotonPRO device in clinical evaluation of athletes (Part B). Twelve professional basketball players participated in Part A of the study (mean age: 19.8 ± 2.4 years, body height 197 ± 8.2 cm, body mass: 91.8 ± 11.8 kg), with unilateral neck or shoulder pain at the dominant side. Part B tested twelve right-handed male athletes (mean ± SD; age: 20.4 ± 1.2 years; body height: 178.6 ± 7.7 cm; body mass: 73.2 ± 12.6 kg). Stiffness measurements were obtained directly before and after a single session trigger point compression therapy. Measurements were performed bilaterally over 5 points covering the trapezius muscle. The effects were evaluated using a full-factorial repeated measure ANOVA and the Bonferroni post-hoc test for equal variance. A p-value < .05 was considered significant. The RM ANOVA revealed a significant decrease in muscle stiffness for the upper trapezius muscle. Specifically, muscle stiffness decreased from 243.7 ± 30.5 to 215.0 ± 48.5 N/m (11.8%), (p = .008) (Part A). The test-retest relative reliability of trapezius muscle stiffness was found to be high (ICC from 0.821 to 0.913 for measurement points). The average SEM was 23.59 N/m and the MDC 65.34 N/m, respectively (Part B). The present study showed that a single session of compression trigger point therapy can be used to significantly decrease the stiffness of the upper trapezius among professional basketball players.

A critical overview of the current myofascial pain literature - July 2018

In the current issue of this clinical overview, we are pleased to include several basic research studies ranging from the differentiation of radicular and non-radicular low back pain based on the presence of trigger points (TrPs) to the role of TrPs in patients with osteoarthritis, the diagnostic criteria of TrP, the accurate placement of needles in the piriformis muscle with dry needling (DN), and the reliability of TrP identification, among others. As usual, there are many new DN studies, but also several review papers, and manual TrP research. Contributing authors come from as many as 15 different countries!

Evidence of Generalized Muscle Stiffness in the Presence of Latent Trigger Points Within Infraspinatus

OBJECTIVE

To evaluate stiffness of infraspinatus muscle tissue, both with and without latent trigger points, using ultrasound shear wave elastography (SWE). The primary hypothesis is that muscle with a latent trigger point will demonstrate a discrete region of increased shear wave speed. The secondary hypothesis is that shear wave speed (SWS) in the region with the trigger point will be higher in patients compared with controls, and will be similar between the two groups in the uninvolved regions.

DESIGN

Case-control.

SETTING

Hospital-based outpatient physical therapy center.

PARTICIPANTS

Convenience sample (N=18) of patients (6 female, 3 male, mean age=44) (range=31-61y) diagnosed with latent trigger points in infraspinatus and matched controls without trigger points.

MAIN OUTCOME MEASURES

Shear wave speed (m/s).

RESULTS

SWS of the latent trigger point (mean=4.09±SD1.4 m/s) did not differ from the adjacent muscle tissue (3.92±1.6 m/s, P>.05), but was elevated compared to corresponding tissue in controls (2.8±0.75 m/s, P=.02). SWS was generally greater in patients' uninvolved tissue (3.83±1.6 m/s) when compared to corresponding tissue in controls (2.62±0.2 m/s, P=.05).

CONCLUSION

Although discrete regions of increased SWS corresponding to the trigger point were not observed in patients, evidence of generally increased muscle stiffness in infraspinatus was exhibited compared to healthy controls. Further study of additional muscles with SWE is warranted.

The effect of dry needling on spasticity, gait and muscle architecture in patients with chronic stroke: A case series study

Objectives The objective of this study was to assess the short-term effects of dry needling on spasticity, gait, and muscle architecture of patients with chronic stroke. Methods A case series study was designed; and six chronic stroke patients with ankle spasticity and gait impairment received a single session of dry needling for gastrocnemius medialis, lateralis, and soleus muscles. The main outcome measures were the Modified Modified Ashworth Scale (MMAS), and Timed Up and Go test (TUG). In addition, ultrasonography measurements (e.g. thickness, pennation angle, and fascicle length) were performed for gastrocnemius medialis at baseline (T0), immediately after intervention (T1) and 30 min after intervention (T2), while the MMAS and TUG Test were only measured at T0 and T2. Results Based on the TUG test, there was a significant improvement in gait function (p = 0.023). Furthermore, the MMAS results (p = 0.014) showed a decrease in resistance to passive movements from plantar flexor muscles. Furthermore, a significant decrease in pennation angle (p = 0.014) and muscle thickness (p = 0.001), and also a significant increase in fascicle length of gastrocnemius medialis (p = 0.001) were observed after dry needling. Discussion & conclusions Based on the outcomes of this study, dry needling application seems to have short term effects in terms of reducing spasticity, improving gait, and muscle architecture of gastrocnemius medialis in patients with chronic stroke. The changes of muscle architecture may be interpreted as the positive effects of dry needling on the physical properties of hypertonic muscles.

Comparing Trigger Point Dry Needling and Manual Pressure Technique for the Management of Myofascial Neck/Shoulder Pain: A Randomized Clinical Trial

OBJECTIVE

The aim of this study was to investigate short-term and long-term treatment effects of dry needling (DN) and manual pressure (MP) technique with the primary goal of determining if DN has better effects on disability, pain, and muscle characteristics in treating myofascial neck/shoulder pain in women.

METHODS

In this randomized clinical trial, 42 female office workers with myofascial neck/shoulder pain were randomly allocated to either a DN or MP group and received 4 treatments. They were evaluated with the Neck Disability Index, general numeric rating scale, pressure pain threshold, and muscle characteristics before and after treatment. For each outcome parameter, a linear mixed-model analysis was applied to reveal group-by-time interaction effects or main effects for the factor "time."

RESULTS

No significant differences were found between DN and MP. In both groups, significant improvement in the Neck Disability Index was observed after 4 treatments and 3 months (P < .001); the general numerical rating scale also significantly decreased after 3 months. After the 4-week treatment program, there was a significant improvement in pain pressure threshold, muscle elasticity, and stiffness.

CONCLUSION

Both treatment techniques lead to short-term and long-term treatment effects. Dry needling was found to be no more effective than MP in the treatment of myofascial neck/shoulder pain.

Assessing the viscoelastic properties of upper trapezius muscle: Intra- and inter-tester reliability and the effect of shoulder elevation

BACKGROUND

Increasing stiffness in the upper trapezius muscle may contribute to imbalance of scapular motion, and result in shoulder and neck discomfort during shoulder flexion. Therefore, it is essential to quantify upper trapezius stiffness in various shoulder positions in order to aid in the prevention of these disorders and to optimize rehabilitation.

OBJECTIVES

The objectives of the present study were to examine the intra and inter-tester reliability of MyotonPRO device in measuring upper trapezius stiffness and its ability to determine changes in stiffness during shoulder flexion.

METHODS

Twenty healthy male subjects (mean age: 28.3±4.8 years) were studied. The stiffness of upper trapezius was quantified using the MyotonPRO device.

RESULTS

The results revealed excellent intra and inter-tester reliability for measuring upper trapezius stiffness with the shoulder in a neutral position, and also found a 14.2% increase in stiffness upon shoulder flexion between 0° and 60° of flexion. Minimal detectable change (MDC) was 26.3 N/m.

CONCLUSIONS

Our findings indicate that MyotonPRO device is a feasible tool to quantify upper trapezius stiffness as well as changes in muscle stiffness. Thus, it is important to assess the changes in upper trapezius muscle stiffness due to pathology or treatments for future studies.

Reliability of the Upper Trapezius Muscle and Fascia Thickness and Strain Ratio Measures by Ultrasonography and Sonoelastography in Participants With Myofascial Pain Syndrome

Objective

The purpose of this study was to assess the intra- and interexaminer reliability of the upper trapezius muscle and fascia thickness measured by ultrasonography imaging and strain ratio by sonoelastography in participants with myofascial pain syndrome.

Methods

Thirty-two upper trapezius muscles were assessed. Two examiners measured the upper trapezius thickness and strain ratio 3 times by ultrasonography and sonoelastography independently in the test session. The retest session was completed 6 to 8 days later.

Results

A total of 87.5% of participants had trigger points on the right side, and 22.5% had trigger points on the left side. For the test session, the average upper trapezius thickness, fascia thickness, and strain ratio measured by first and second examiners were 11.86 mm and 11.56 mm, 1.23 mm and 1.25 mm, and 0.94 and 0.99, respectively. For the retest session, the previously mentioned parameters obtained by first and second examiners were 11.76 mm and 11.39 mm, 1.27 mm and 1.29 mm, and 0.96 and 0.99, respectively. The intraclass correlation coefficients indicated good to excellent reliability for both within-intraexaminer (0.78-0.96) and between-intraexaminer (0.75-0.98) measurements. Also, the intraclass correlation coefficients and standard errors of measurement of interexaminer reliability ranged between 0.88 to 0.93 and 0.05 to 0.44 for both muscle and fascia thickness and 0.70 to 0.75 and 0.04 to 0.20 for strain ratio of upper trapezius, respectively.

Conclusion

Upper trapezius thickness measurements by ultrasonography and strain ratio by sonoelastography are reliable methods in participants with myofascial pain syndrome.

Novel method to measure active myofascial trigger point stiffness using ultrasound imaging

INTRODUCTION

Myofascial trigger points (MTrPs) are one of the most common and important causes of musculoskeletal pain. Ultrasound is a useful modality in examining musculoskeletal disorders. By applying compressive stress and observing changes in ultrasound images, the elastic modulus (Young's modulus) can be calculated. Our objective was to develop a novel method to distinguish MTrPs from normal tissues.

METHODS

A total of 29 subjects with MTrP in the sternocleidomastoid muscle were assessed. A force gauge was attached to a transducer to obtain stress levels. To obtain strain, images were recorded in both with stress and without stress states. By dividing the stress level by the measured strain, the elastic modulus was determined.

RESULTS

Elastic modulus in MTrPs and the normal part of the muscle were measured to be 13379.57 ± 1069.75Pa and 7078.24 ± 482.92Pa, respectively (P = 0.001). This indicated that MTrPs were stiffer than normal parts of the muscle.

CONCLUSION

This study presents a new method for the quantitative measurement of the elastic modulus of MTrP, thereby distinguishing MTrPs from normal adjacent muscular tissue, with more simplicity and lower cost, compared to other ultrasound methods.

Assessment of the mechanical properties of the muscle-tendon unit by supersonic shear wave imaging elastography: a review

This review aimed to describe the state of the art in muscle-tendon unit (MTU) assessment by supersonic shear wave imaging (SSI) elastography in states of muscle contraction and stretching, during aging, and in response to injury and therapeutic interventions. A consensus exists that MTU elasticity increases during passive stretching or contraction, and decreases after static stretching, electrostimulation, massage, and dry needling. There is currently no agreement regarding changes in the MTU due to aging and injury. Currently, the application of SSI for the purpose of diagnosis, rehabilitation, and physical training remains limited by a number of issues, including the lack of normative value ranges, the lack of consensus regarding the appropriate terminology, and an inadequate understanding of the main technical limitations of this novel technology.

Referred Pain Patterns of the Infraspinatus Muscle Elicited by Deep Dry Needling and Manual Palpation

OBJECTIVES

To identify the most common referred pain (ReP) pattern of the infraspinatus myofascial trigger point (MTrP) and compare its coincidence with the original ReP pattern, to verify whether there are any significant differences by sex and types of technique and to determine the observed signs and symptoms evoked by deep dry needling (DDN) and manual palpation (MPal).

DESIGN

A cohort study of patients randomized to two different examination methods (July and August 2016).

SETTINGS

Students and staff recruited from Miguel Hernandez University (Southeast Spain).

PATIENTS

One hundred thirty-three participants (70.7% women) with shoulder complaints were randomly assigned to either an MPal (n = 67) or DDN group (n = 66).

INTERVENTIONS

The same physiotherapist carried out the techniques on all participants, and the same protocol was followed for both the DDN and MPal groups. The physiotherapist did not ask participants about their pain features or other relevant issues.

OUTCOME MEASURES

Local twitch response (LTR) and ReP assessed through a visual analogue scale and features of ReP of the infraspinatus muscle.

RESULTS

The areas with the highest percentage of ReP were the front (area 3; 27.1%) and back (area 11; 21.1%) of the arm, anterior (area 4; 36.1%) and posterior (area 12; 42.1%) shoulder, and infraspinatus muscle area. DDN proved to be significantly easier than MPal in evoking an LTR (p ≤ 0.001). There were significant differences between sexes in zone 2 (p = 0.041) and no statistically significant differences were found by technique.

CONCLUSIONS

The ReP pattern of the infraspinatus muscle coincides with the original pattern described by Travell and Simons, although the neck area should be questioned. The study found no significant differences in the ReP pattern by sex and when comparing MPal with DDN of MTrP of the infraspinatus muscle. DDN proved to be significantly easier than MPal in evoking an LTR.