Effects of transcutaneous radiofrequency diathermy versus ultrasound on latent myofascial trigger points in the upper trapezius: A randomized crossover trial

BACKGROUND

Currently, the use of radiofrequency diathermy for the treatment of neck pain is booming.

OBJECTIVE

This study aimed to evaluate the clinical efficacy of Digital Capacitive Diathermy (DCD®) on stiffness, pain, cervical range of motion, and cervical disability and to compare it with ultrasound (US) in patients with latent myofascial trigger point (MTrP) in the upper trapezius.

METHODS

Nineteen participants with latent MTrPs in the upper trapezius were included in the assessor-masked, randomized, clinical crossover trial. Subjects were exposed to both interventions: US and DCD® and treatment effectiveness was measured by myotonometric variables, pressure pain threshold (PPT), visual analog scale (VAS), cervical side-bending flexion ranges, and the neck disability index scale (NDI).

RESULTS

There were no significant differences between US and DCD® interventions regarding changes in outcome measures. The US group achieved a statistically significant difference of 2.16 to 1.13 points (p= 0.005; r= 0.646) for the VAS. The DCD® intervention showed a statistically significant improvement of 1.11 points for the NDI at 1-week following intervention (95% CI 0.14-2.07; p= 0.27; d= 0.217).

CONCLUSION

Our findings suggest that DCD® and US can both be considered effective modalities for the treatment of latent MTrPs, having a longer duration of action with DCD® therapy.

Effectiveness of ultrasound guided interfascial hydrodissection with the use of saline anesthetic solution for myofascial pain syndrome of the upper trapezius: a single blind randomized controlled trial

Background

Myofascial pain syndrome (MPS) is described as pain that arise from myofascial trigger points (MTrPs) which is a hyperirritable spot within a taut band of skeletal muscle. A newer needling technique called the interfascial hydrodissection (IH), wherein anesthetic saline solution (ASS) is injected between the fascia of the muscles using ultrasound as guide. It is theorized that this technique blocks the nerve branches and improve gliding in between the muscle and fascia.

Objective

To determine the short and long-term effects of interfascial hydrodissection using 2% Lidocaine and saline solution compared to dry needling with MPS of the upper trapezius on pain and quality of life using.

Methods

This study is a single-blind randomized controlled trial where ultrasound guided IH with ASS was compared to dry needling (DN) of the MTrPs. Both groups were taught self-stretch exercises (SSE) to be done everyday after the procedure. Outcome measures were pain using the visual analogue scale (VAS) and quality of life assessment with EQ-5D-5l questionnaire. All participants were assessed by a blinded assessor before the intervention, immediately after, 10 and 30 min, one week, two weeks, four weeks, three months, and six months after the procedure. Data Analysis: Two-way mixed ANOVA and follow-up independent T-test were conducted for the outcome measures across several time points between the 2 groups.

Results

A total of 46 participants with two dropouts were all included during the final analysis. Both groups demonstrated significant differences in VAS scores between baseline and the different time points, the IH + SSE group demonstrated the more significant effect size at as compared to the DN + SSE group. For EQ-5D-5l, no statistical differences were seen in all dimensions but there was a larger effect size for usual activities, pain/discomfort and anxiety/depression.

Conclusion

Interfascial hydrodissection is a technique that can manage both short and long term symptoms of MPS. This could be utilized as an alternative management for those with chronic MPS of the upper trapezius.

Philippine Health Research Registry ID

PHRR221003-005034.

Which muscles exhibit increased stiffness in people with chronic neck pain? A systematic review with meta-analysis

Introduction

Chronic neck pain (CNP) substantially impacts quality of life, posing both personal challenges and economic strains. This systematic review sought to discern muscle-specific stiffness differences between CNP patients and individuals without CNP.

Methods

We searched the PubMed, Scopus, and PEDro databases for studies using ultrasound elastography or myotonometry to compare muscle stiffness between CNP patients and asymptomatic controls. Using a meta-analysis with a random-effects model, we derived the pooled effect as standardized mean difference (SMD).

Results

Out of the six studies selected, the adjusted Newcastle-Ottawa rating scale for cross-sectional studies denoted three as moderate-quality and three as high-quality. Our findings indicate that the upper trapezius (UT) stiffness was elevated in CNP patients compared to their counterparts without CNP (SMD = 0.39, 95% CI = 0.05 to 0.74; p = 0.03; small effect size). The data for other muscles remained inconclusive.

Discussion

Given the case-control design of all reviewed studies, a direct causative link between UT stiffness and CNP is yet to be confirmed. As such, recommending a reduction in trapezius muscle stiffness as a primary rehabilitation strategy for CNP patients is still inconclusive and further research is needed.

Symmetry of the Neck Muscles' Activity in the Electromyography Signal during Basic Motion Patterns

The activity of muscles during motion in one direction should be symmetrical when compared to the activity of the contralateral muscles during motion in the opposite direction, while symmetrical movements should result in symmetrical muscle activation. The literature lacks data on the symmetry of neck muscle activation. Therefore, this study aimed to analyse the activity of the upper trapezius (UT) and sternocleidomastoid (SCM) muscles at rest and during basic motions of the neck and to determine the symmetry of the muscle activation. Surface electromyography (sEMG) was collected from UT and SCM bilaterally during rest, maximum voluntary contraction (MVC) and six functional movements from 18 participants. The muscle activity was related to the MVC, and the Symmetry Index was calculated. The muscle activity at rest was 23.74% and 27.88% higher on the left side than on the right side for the UT and SCM, respectively. The highest asymmetries during motion were for the SCM for the right arc movement (116%) and for the UT in the lower arc movement (55%). The lowest asymmetry was recorded for extension-flexion movement for both muscles. It was concluded that this movement can be useful for assessing the symmetry of neck muscles' activation. Further studies are required to verify the above-presented results, determine muscle activation patterns and compare healthy people to patients with neck pain.

Effects of Artificially Induced Breast Augmentation on the Electromyographic Activity of Neck and Trunk Muscles during Common Daily Movements

A female breast can be a potential source of musculoskeletal problems, especially if it is disproportionately large. The purpose of the present study was to examine the effect of artificially induced breast volume on the EMG activity of neck and trunk musculature during common everyday movements. The EMG activity of the sternocleidomastoid (SCM), the upper trapezius (UT), and the thoracic and lumbar erector spinae (TES, LES) were recorded during 45° trunk inclination from the upright standing and sitting postures (TIST45°, TISI45°) as well as during stand-to-sit and sit-to-stand (STSI, SIST) in 24 healthy females with minimal and ideal breast volume (M-NBV, I-NBV). All movements were performed before and after increasing M-NBV and I-NBV by 1.5-, 3.0-, 4.5-, and 6-times using silicone-gel implants. Significantly higher EMG activity for TES and LES were found at 6.0- and ≥4.5-times increase the I-NBV, respectively, compared to smaller breast volumes during TIST45°. EMG activity of UT was higher, and TES was lower in M-NBV females compared to I-NBV females in all movements but were significantly different only during SIST. The female breast can affect the activity of neck and trunk muscles only when its volume increases above a certain limit, potentially contributing to muscle dysfunction.

Influencing factors of pressure pain hypersensitivity of the upper trapezius in food service workers with nonspecific neck/shoulder myofascial pain: A cross-sectional study

It is unclear which factors contribute to the developing pressure pain hypersensitivity of the upper trapezius, a type of neurophysiological hyperexcitability. The present study investigated the relationship between physical and psychological factors and pressure pain hypersensitivity of the upper trapezius for each sex. In total, 154 individuals with neck/shoulder myofascial pain participated, among 372 food service workers. Participants completed a questionnaire (Beck Depression Inventory, and Borg Rating of Perceived Exertion scale) and were photographed to measure posture. Pressure pain sensitivity, 2 range of motions (cervical lateral bending and rotation), and 4 muscle strengths (serratus anterior, lower trapezius [LT], biceps, and glenohumeral external rotator) were measured by a pressure algometer, iPhone application, and handheld dynamometer, respectively. For each sex, forward multivariate logistic regression was used to test our a priori hypothesis among selected variables that a combination of psychosocial and physical factors contributed to the risk for pressure pain hypersensitivity. In multivariate analyses, LT strength (odds ratio = 0.94, 95% confidence interval = 0.91-0.97, P = .001) was the only significant influencing factor for pressure pain hypersensitivity in men. Dominant painful ipsilateral cervical rotation range of motion (odds ratio = 0.96, 95% confidence interval = 0.92-0.99, P = .037) was the only influencing factor for pressure pain hypersensitivity in women. LT strength and dominant painful ipsilateral cervical rotation range of motion could serve as guidelines for preventing and managing pressure pain hypersensitivity of the upper trapezius in food service workers with nonspecific neck/shoulder myofascial pain.

Relationships between alexisomia and the presence of latent trigger points in the upper trapezius of healthy volunteers

BACKGROUND

Alexisomia is characterized by difficulties in the awareness and expression of somatic feelings. Trigger points are classified into two types, active and latent, according to the presence or absence of identifying spontaneous pain.

OBJECTIVE

We aimed to examine the association between alexisomia and the presence of latent trigger points (LTrPs) in the upper trapezius of healthy volunteers.

METHODS

This study was designed as a cross-sectional survey. A correlation analysis between the Shitsu-Taikan-Sho Scale (STSS) and LTrPs was performed on 154 healthy volunteers. The LTrP odds ratio for healthy volunteers with alexisomia was selected as the primary endpoint.

RESULTS

LTrPs were seen in the upper trapezius of 82 healthy volunteers (53.2%). There was no significant difference between the LTrP and non-LTrP groups in STSS total score (p= 0.11). However, there was a significant difference between them in STSS difficulty of identifying bodily feelings (DIB) score (p= 0.03). In the alexisomic versus non-alexisomic groups, the LTrP odds ratio for STSS total score was 2.30 (95% confidence interval [CI] 1.03-5.10) and for STSS DIB score, 2.08 (95% CI 1.05-4.11).

CONCLUSIONS

In STSS DIB in particular, alexisomia was associated with the presence of LTrP in the upper trapezius of healthy volunteers.

Pressure pain thresholds in office workers with chronic neck pain: A systematic review and meta-analysis

OBJECTIVES

The purpose of this study was to (a) compare pressure pain threshold (PPT) values between office workers with chronic neck pain and asymptomatic controls; (b) establish reference PPT values in chronic neck pain; and (c) evaluate associations between PPTs and pain intensity, and disability.

METHODS

Seven English/Portuguese databases were searched for relevant literature. Studies investigating adult office workers (age >18 years) with chronic neck pain were included if PPTs were an outcome. The risk of bias was assessed using the Downs and Black checklist. Meta-analysis was conducted if a cluster contained at least two studies reporting the same PPTs.

RESULTS

Ten high quality, two low quality, and one poor quality studies were included. The meta-analysis revealed decreased PPT values in the upper trapezius, extensor carpi ulnaris, and tibialis anterior in office workers with chronic neck pain when compared with healthy workers, without a statistical difference (p > 0.05). The PPT reference value in the upper trapezius was 263 kPa (95% confidence interval [CI] = 236.35 to 289.70), and 365 kPa (95% CI = 316.66 to 415.12) for the tibialis anterior in office workers with chronic neck pain. No correlations were found between the upper trapezius PPT and pain intensity and disability.

CONCLUSION

This meta-analysis found that all the PPT measurements were not significantly reduced in office workers with chronic neck pain compared with healthy workers. These assumptions were based on a small sample of existing studies, and therefore further studies are necessary to quantify the differences in PPTs. Hypersensitivity PPT reference values are proposed for localized and extrasegmental sites in office workers with chronic neck pain.

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.

Differences in scapular motion and parascapular muscle activities among patients with symptomatic and asymptomatic rotator cuff tears, and healthy individuals

Background

Altered scapular motion is thought to be one of the factors associated with the development of symptomatic rotator cuff tears. However, the differences in kinematics and muscle activities of scapular upward/downward rotation between patients with symptomatic and asymptomatic tears are unclear. The purpose of this study was to compare the differences in kinematics and muscle activities of scapular rotation among patients with symptomatic and asymptomatic tears, and healthy individuals.

Methods

Twenty-three patients with rotator cuff tears and 9 healthy individuals (healthy group) participated in this study. Based on a visual analog scale (VAS, 0-100 mm), the patients were divided into symptomatic (13 patients; VAS ≥20 mm) and asymptomatic (10 patients; VAS <20 mm) groups. Scapular upward rotation was measured with a digital inclinometer. Elasticities of the upper trapezius, levator scapulae, and rhomboid major were assessed by using ultrasound real-time tissue elastography to quantify their muscle activities. All measurements were performed at 0°, 60°, 90°, and 120° of active arm elevation in the scapular plane.

Results

Scapular upward rotation was significantly less in the symptomatic group (9.4° ± 5.6°) compared with the asymptomatic group (15.7° ± 6.0°; P = .022) at 90° of arm elevation. The activity of the levator scapulae was significantly higher in the symptomatic group compared with the asymptomatic and healthy groups (P = .013 and P = .005, respectively) at 90° of arm elevation. The activity of the upper trapezius was significantly higher in the symptomatic group compared with the healthy group (P = .015) at 120° of arm elevation.

Conclusion

Patients with symptomatic rotator cuff tears showed less scapular upward rotation and higher activity of the levator scapulae at 90° of arm elevation compared to patients with asymptomatic rotator cuff tears.

Rate and maintenance of improvement of myofascial pain with dry needling alone vs. dry needling with intramuscular electrical stimulation: a randomized controlled trial

STUDY DESIGN

Prospective, randomized.

OBJECTIVES

To determine the difference in rate and maintenance of improvement of pain and disability for Dry Needling (DN) compared to Dry Needling with Intramuscular Electrical Stimulation (DN/IMES), in Myofascial Pain Syndrome (MPS).

BACKGROUND

DN and neuromuscular electrical stimulation (NMES) have been shown to be efficacious in treating MPS. DN/IMES for MPS treatment has not been studied extensively, but initial results are promising.

METHODS

Forty-five subjects were randomly assigned to the DN (n = 25) or DN/IMES (n = 20) group. Both groups received six consecutive weekly treatments and completed NDI and NPRS questionnaires (week 0, 3, 6, and 12).

RESULTS

Both DN and DN/IMES groups showed significant improvement between weeks 0-6 on NDI (p = 0.008 and 0.00002, respectively) and NPRS scores (0 = 0.017 and p = 0.018, respectively). DN/IMES group showed significant within group changes on the NPRS between weeks 0-3 (p = 0.029). No changes were noted in the DN or DN/IMES groups between week 6-12 on NDI (p = 0.497 and p = 0.714, respectively) or NPRS (p = 0.801 and p = 0.164, respectively).

CONCLUSION

DN and DN/IMES demonstrated improvement and maintenance in disability and pain for 6 weeks. No differences in improvement of disability or pain existed between the groups at week 6 or 12.

An Electromyographic Analysis of Lateral Raise Variations and Frontal Raise in Competitive Bodybuilders

The present study examined the muscle activation in lateral raise with humerus rotated externally (LR-external), neutrally (LR-neutral), internally (LR-internal), with flexed elbow (LR-flexed) and frontal raise during both the concentric and eccentric phase. Ten competitive bodybuilders performed the exercises. Normalized surface electromyographic root mean square (sEMG RMS) was obtained from anterior, medial, and posterior deltoid, pectoralis major, upper trapezius, and triceps brachii. During the concentric phase, anterior deltoid and posterior deltoid showed greater sEMG RMS in frontal raise (effect size (ES)-range: 1.78/9.25)) and LR-internal (ES-range: 10.79/21.34), respectively, vs. all other exercises. Medial deltoid showed greater sEMG RMS in LR-neutral than LR-external (ES: 1.47 (95% confidence-interval—CI: 0.43/2.38)), frontal raise (ES: 10.28(95% CI: 6.67/13.01)), and LR-flexed (ES: 6.41(95% CI: 4.04/8.23)). Pectoralis major showed greater sEMG RMS in frontal raise vs. all other exercises (ES-range: 17.2/29.5), while upper trapezius (ES-range: 2.66/7.18) and triceps brachii (ES-range: 0.41/3.31) showed greater sEMG RMS in LR-internal vs. all other exercises. Similar recruitment patterns were found during the eccentric phase. When humerus rotates internally, greater activation of posterior deltoid, triceps brachii, and upper trapezius occurs. Humerus external rotation increases the activation of anterior and medial deltoid. Frontal raise mainly activates anterior deltoid and pectoralis major. LR variations and frontal raise activate specifically shoulders muscles and should be proposed accordingly.

The effect of dry needling on the active trigger point of upper trapezius muscle: Eliciting local twitch response on long-term clinical outcomes

BACKGROUND

Pain from myofascial trigger points is often treated by dry needling (DN). Empirical evidence suggests eliciting a local twitch response (LTR) during needling is essential. Muscle damage after eliciting LTR can increase the risk of tissue fibrosis in some cases.

OBJECTIVE

This study aimed to compare two methods of DN including with and without LTR on clinical parameters.

METHODS

Twenty-six participants suffering from chronic non-specific neck pain with an active trigger point (TrP) in their upper trapezius muscles were recruited via the convenience sampling method. Participants were randomly assigned in DN with LTR (control group) and without eliciting LTR or "de qi" (experimental group). Then, they received 3 sessions of dry needling, 3 days apart. We evaluated pain, pain pressure threshold, active cervical lateral flexion range of motion, and Neck Disability Index before the intervention and 4 weeks after the treatment.

RESULTS

After the treatment, significant higher changes were seen in the experimental group compared to the control group (p< 0.05) regarding pain, pain pressure threshold, and active cervical lateral flexion. However, there was no significant difference between groups according to the disability (p> 0.05).

CONCLUSION

DN without eliciting LTR has superiority over the DN along with eliciting LTR while the treatment aimed to receive long-term effects.

SCAPULAR MUSCLE ELECTROMYOGRAPHIC ACTIVITY DURING ABDUCTION EXERCISES IN THE SCAPULAR PLANE IN THREE POSITIONS

BACKGROUND

Hyperactivity of the anterior deltoid (AD) has been shown to produce adverse effects on subacromial space width as a result of humeral head superior translation during rehabilitation exercises used with overhead athletes. Also, the importance of the ratio of upper trapezius (UT) to lower trapezius (LT) muscle activity has been examined during rehabilitation exercises particularly for those who develop scapular dyskinesis.

HYPOTHESIS/PURPOSE

The purpose of this study was to investigate the level of LT and SA muscle activity during scapular plane elevation (scaption) in three positions while maintaining a moderate level of AD muscle activity. A secondary purpose was to identify the ratio of UT to LT muscle activity during the varied scaption exercises. The authors hypothesized that the activation of these two important muscles and the UT/LT ratio would vary with exercise position and throughout the range of scapular plane elevation.

METHODS

Fourteen active young subjects performed scaption exercises in three different positions: standing (STAN), quadruped (QUAD), and prone (PRON) with three different weight loads: 0 kg, 1.8 kg, and 4.1 kg. Surface electromyography (EMG) was used to record muscular activity. Tested muscles included the UT, LT, SA, AD, and posterior deltoid muscles on the dominant side.

RESULTS

QUAD scaption exercises with a load of 1.8 kg at 4 sec after the initial movement activated the LT muscle up to 49% of maximum voluntary isometric contraction (MVIC) while maintaining a moderate level of AD muscle activity (30% MVIC). STAN scaption exercises with the weight load of 1.8 kg at 3 sec after the initial movement activated 43% MVIC of the SA muscle while maintaining a moderate level of AD muscle activity (39% MVIC). The PRON condition generated significantly less SA muscle activity with both 1.8 and 4.1 kg weight loads than during the QUAD condition. The ratios of UT to LT muscle activity were significantly less in QUAD than those of STAN up to 4 sec after the initial movement. No significant difference was observed in the UT/LT ratio between QUAD and PRON conditions.

CONCLUSION

QUAD scaption exercise effectively activated both LT and SA muscles without over activating the AD and produced favorable ratios of UT to LT muscle activity.

LEVEL OF EVIDENCE

Descriptive Cohort Study, Level 4.

Comparison of scapular muscle activation during shoulder elevation in older and young adults: A pilot study

BACKGROUND

The prevalence of degenerative shoulder disease is increasing, and most shoulder diseases are accompanied by changed activation of the scapular muscles. However, the characteristics of scapular muscle activation in older adults have not yet been reported.

OBJECTIVE

The aim of this study was to investigate the effect of age and load on scapular muscle activation during shoulder abduction and flexion.

METHODS

Eleven older adults (5 men, 6 women; 71.1 ± 5.3 years) and ten young adults (5 men, 5 women; 25.0 ± 2.7 years) performed shoulder elevation (abduction and flexion) with and without a dumbbell. Electromyography were recorded from the upper, middle and lower trapezius, and serratus anterior muscles in the dominant side. Muscle activation was normalized by reference voluntary contractions.

RESULTS

During shoulder elevation with a dumbbell load, the activation of the middle trapezius (p= 0.036) in older adults was significantly higher than that in young adults during abduction. The activation of the upper trapezius (p= 0.001) in older adults was significantly higher than that in young adults during flexion.

CONCLUSION

The older adults have a higher activation of the upper and middle trapezius during shoulder elevation with a weighted load.

Human motor unit characteristics of the superior trapezius muscle with age-related comparisons

Current understanding of human motor unit (MU) control and aging is mostly derived from hand and limb muscles that have spinal motor neuron innervations. The aim here was to characterize and test whether a muscle with a shared innervation supply from brainstem and spinal MU populations would demonstrate similar age-related adaptations as those reported for other muscles. In humans, the superior trapezius (ST) muscle acts to elevate and stabilize the scapula and has primary efferent supply from the spinal accessory nerve (cranial nerve XI) located in the brainstem. We compared electrophysiological properties obtained from intramuscular and surface recordings between 10 young (22-33 yr) and 10 old (77-88 yr) men at a range of voluntary isometric contraction intensities (from 15 to 100% of maximal efforts). The old group was 41% weaker with 43% lower MU discharge frequencies compared with the young (47.2 ± 9.6 Hz young and 26.7 ± 5.8 Hz old, P < 0.05) during maximal efforts. There was no difference in MU number estimation between age groups (228 ± 105 young and 209 ± 89 old, P = 0.33). Furthermore, there were no differences in needle detected near fiber (NF) stability parameters of jitter or jiggle. The old group had lower amplitude and smaller area of the stimulated compound muscle action potential and smaller NF MU potential area with higher NF counts. Thus, despite age-related ST weakness and lower MU discharge rates, there was minimal evidence of MU loss or compensatory reinnervation.NEW & NOTEWORTHY The human superior trapezius (ST) has shared spinal and brainstem motor neuron innervation providing a unique model to explore the impact of aging on motor unit (MU) properties. Although the ST showed higher MU discharge rates compared with most spinally innervated muscles, voluntary strength and mean MU rates were lower in old compared with young at all contraction intensities. There was no age-related difference in MU number estimates with minimal electrophysiological evidence of collateral reinnervation.

Dry needling versus trigger point compression of the upper trapezius: a randomized clinical trial with two-week and three-month follow-up

Objectives: The purpose of this randomized controlled trial was to investigate the long-term clinical effect of dry needling with two-week and three-month follow up, on individuals with myofascial trigger points in the upper trapezius muscle. Methods: A sample of convenience (33 individuals) with a trigger point in the upper trapezius muscle, participated in this study. The individuals were randomly assigned to two groups: trigger point compression (N = 17) or dry needling (N = 16). Pain intensity, neck disability, and disability of the arm, hand, and shoulder (DASH) were assessed before treatment, after treatment sessions, and at two-week and three-month follow ups. Results: The result of repeated measures ANOVA showed significant group-measurement interaction effect for VAS (p = .02). No significant interaction was found for NPQ and DASH (p > .05). The main effect of measurements for VAS, NPQ, and DASH were statistically significant (p < .0001). The results showed a significant change in pain intensity, neck disability, and DASH after treatment sessions, after two weeks and three months when compared with before treatment scores in both groups.  There was no significant difference in the tested variables after two-week or three-month as compared to after treatment sessions between the two groups. However, pain intensity after treatment sessions was significantly different between the two groups (p = .02). Discussion: Dry needling and trigger point compression in individuals with myofascial trigger point in the upper trapezius muscle can lead to three-month improvement in pain intensity and disability.

High- versus low-energy extracorporeal shock-wave therapy for myofascial pain syndrome of upper trapezius: A prospective randomized single blinded pilot study

BACKGROUND

To compare the efficacy of high- and low-energy extracorporeal shock wave therapy (ESWT) for patients with myofascial pain syndrome (MPS) of the upper trapezius.

METHODS

Thirty patients (3 men, 27 women) were randomly assigned to receive either high-energy ESWT (0.210 mJ/mm) or low-energy ESWT (0.068 mJ/mm). Both groups received 1500 pulses of ESWT once a week, for 2 weeks. Outcome measurement was assessed by verbal numeric pain scale (VNS), neck disability index (NDI), neck range of motion (ROM) (flexion, extension, rotation, lateral bending), and pressure threshold (PT). Statistical analysis was performed with significance level of P < .05.

RESULTS

No statistically significant differences of demographic and clinical characteristics existed between the 2 groups. VNS, NDI, neck ROM (rotation to sound side, lateral bending to affected side, lateral bending to sound side), and PT were improved in both groups. In contrast, statistically significant improvements in neck flexion and neck extension were observed only in the high-energy group. We also found significant differences in post-treatment NDI (4.20 ± 1.78 vs 6.47 ± 2.48) and post-treatment neck flexion ROM (65.47 ± 10.09 vs 55.93 ± 11.07) between high-energy and low-energy group.

CONCLUSION

ESWT effectively improves VNS, NDI, neck ROM, and PT to patients with MPS of the upper trapezius. High-energy ESWT was more effective in improving NDI and neck flexion ROM compared to the low-energy ESWT, suggesting superiority in functional improvement. Further studies are required to specify the effect of ESWT by energy intensity.

Comparative study of shock wave therapy and Laser therapy effect in elimination of symptoms among patients with myofascial pain syndrome in upper trapezius

BACKGROUND

The aim of this study is to compare the effects of laser therapy and shock wave therapy for symptoms treatment among patients with MPS in the upper trapezius muscle.

MATERIALS AND METHODS

In a clinical trial study, 46 patients were selected based on the clinical criteria and physiathrist diagnosis. Subjects were randomized into two groups as follows: Twenty individuals were assigned to exercise-medication-laser therapy group, and 26 to exercise-medication-shock wave therapy group. The pain was assessed based on visual analog scale (VAS), neck disability index (NDI), and SPADI in three stages: Before treatment, subsequently after treatment, and a month after treatment.

RESULTS

One man and 19 women, age group of 45.3 ± 7.7 years, were assigned into laser therapy group. Two men and 24 women, average age group of 42.3 ± 10.4 were assigned into shock wave therapy group. A significant difference was found among our study groups before treatment and after starting treatment for VAS, NDI, and SPDI indices, that is, two methods of treatments were effective (P < 0.001). However, among these two treatment methods, laser therapy provided higher effect on VAS and NDI as compared to the radial shock wave method (P < 0.05) in 2 weeks from starting the treatment (consequent to treatment).

CONCLUSION

According to this study results, we can conclude that shock wave and laser therapy results on similar effect in long-term for relieve of pain and eliminating symptoms in patients with myofascial but laser provides a faster optimal results.

Ultrasonography for the assessment of the upper trapezius properties in healthy females: a reliability study

BACKGROUND

to date, an assessment of morphometric features, muscle stiffness and blood flow in the upper trapezius among healthy females at rest and contraction states has not been conducted. So, in the current research, the intra-rater reliability of ultrasonographic features of upper trapezius in healthy females was examined.

METHOD

in this study stiffness and thickness of the upper trapezius in rest and contraction states were measured by ultrasonography on 12 healthy female subjects (28.33±5.05 years old). Color Doppler imaging was used to assess muscle circulation in the rest state only. Every step and calculation of measurements was repeated 3 times with the same rater. Therefore, in total 36 measurements were done for each variable.

RESULTS

according to the analysis, the value of intra class correlation coefficient (ICC) for total variables showed an excellent level of reliability. Thickness at contraction had maximum reliability (ICC= 0.993) and Minimum Diastolic Velocity had the lowest reliability (ICC=0.771).

CONCLUSIONS

the results of current research demonstrated that real time ultrasonography is a reliable method for measurement of various parameters of upper trapezius, including morphometric features, its stiffness and blood supply in non-symptomatic females. These mentioned variables can likely be used for objective assessment and provide numerical reference value for clinical plans.

Preferential distribution of nociceptive input to motoneurons with muscle units in the cranial portion of the upper trapezius muscle

Pain is associated with changes in the neural drive to muscles. For the upper trapezius muscle, surface electromyography (EMG) recordings have indicated that acute noxious stimulation in either the cranial or the caudal region of the muscle leads to a relative decrease in muscle activity in the cranial region. It is, however, not known if this adaption reflects different recruitment thresholds of the upper trapezius motor units in the cranial and caudal region or a nonuniform nociceptive input to the motor units of both regions. This study investigated these potential mechanisms by direct motor unit identification. Motor unit activity was investigated with high-density surface EMG signals recorded from the upper trapezius muscle of 12 healthy volunteers during baseline, control (intramuscular injection of isotonic saline), and painful (hypertonic saline) conditions. The EMG was decomposed into individual motor unit spike trains. Motor unit discharge rates decreased significantly from control to pain conditions by 4.0 ± 3.6 pulses/s (pps) in the cranial region but not in the caudal region (1.4 ± 2.8 pps; not significant). These changes were compatible with variations in the synaptic input to the motoneurons of the two regions. These adjustments were observed, irrespective of the location of noxious stimulation. These results strongly indicate that the nociceptive synaptic input is distributed in a nonuniform way across regions of the upper trapezius muscle.