The effect of EMG biofeedback training on muscle activation in an impingement population.

Subacromial impingement syndrome (SAIS) is one of the most diagnosed causes of pain in the upper extremity. The purpose of this study was to investigate muscle activity between asymptomatic and SAIS shoulders on the same subject while understanding the effectiveness of EMG biofeedback training (EBFB) on bilateral overhead movements. Ten participants (7 male), that tested positive for 2/3 SAIS clinical tests, volunteered for the study. Bilateral muscle activity was measured via electrodes on the upper trapezius (UT), lower trapezius (LT), serratus anterior (SA), and lumbar paraspinals (LP). Participants performed bilateral scapular plane overhead movements before and after EBFB. EBFB consisted of 10 bilateral repetitions of I, W, T, and Y exercises focused on reducing UT and increasing LT and SA activity. Prior to EBFB, no significant difference in muscle activity was present between sides. A significant main effect of time indicated that after EBFB both sides exhibited reduced UT activity at 60° (p = 0.003) and 90° (p = 0.036), LT activity was increased at all measured humeral angles (p < 0.0005), and SA muscle activity was increased at 110° (p = 0.001). EBFB in conjunction with scapular based exercise effectively alters muscle activity of asymptomatic and symptomatic scapular musculature.

Using biofeedback to optimize scapular muscle activation ratios during a seated resisted scaption exercise.

Impairments in muscle activation have been linked to increased risk of developing shoulder pathologies such as subacromial impingement syndrome (SIS) and associated rotator cuff injuries. Individuals with SIS have demonstrated increased upper trapezius (UT) muscle activation and reduced serratus anterior (SA) and lower trapezius (LT) muscle activation, which can be collectively represented as ratios (UT/SA and UT/LT). Targeted exercise is an important component of shoulder rehabilitation programs to re-establish optimal muscle activation and ratios. Electromyography (EMG) biofeedback during exercise has been shown to reduce UT activation and favorably alter scapular muscle activation ratios, however, a literature gap exists regarding the efficacy of other types of biofeedback. Therefore, we compared the effects of three types of biofeedback (visual EMG, auditory, verbal cues) on UT/SA and UT/LT ratios during a seated resisted scaption exercise in fifteen subjects without shoulder pain. Baseline muscle activation was recorded and compared to real-time muscle activation during each randomized biofeedback trial. All biofeedback types showed improvements in the UT/SA and UT/LT ratios, with visual EMG demonstrating a significant change in UT/LT ratio (p < 0.05). These results suggest that biofeedback could be utilized as a component of rehabilitation programs to prevent or treat shoulder pain.

Comparing exercises with and without electromyographic biofeedback in subacromial pain syndrome: A randomized controlled trial.

BACKGROUND: Deficits in movement and muscle activation of scapulohumeral joint are related to Subacromial Pain Syndrome. Electromyography biofeedback during exercise may enhance muscle activation and coordination, and consequently improve pain and shoulder function. METHODS: This study compared the effects of an exercise protocol with and without using electromyographic biofeedback on pain, function and movement of the shoulder complex in subjects with Subacromial Pain Syndrome. A total of 24 patients with subacromial pain (mean age = 46.2 + 8.1;18 women) were randomized to either therapeutic exercise or exercise plus biofeedback to the trapezius and serratus muscles. Pain and shoulder function were evaluated as the primary outcome and range of motion, muscle strength, electromyographic activity and scapulohumeral kinematics as secondary outcomes. The subjects underwent eight weeks of intervention and comparisons were made between groups in baseline, at 4 weeks, 8 weeks, and at 4 weeks post intervention. FINDINGS: There were differences between groups for pain [mean difference = 1.5 (CI 0.3, 3.2) p = 0.01] at 8 weeks in the Exercise group and scapular upward rotation at 60° of arm elevation [mean difference = 13.9 (CI 0.9, 9.3), p = 0.006] in the Biofeedback group. There was no difference for the other variables of scapular kinematics as well as for shoulder function (DASH), muscle strength, range of motion and electromyographic variables. INTERPRETATION: The addition of Biofeedback to the exercise protocol increased upward rotation of the scapula. However, the volunteers who performed only the Exercises had a better response in reducing pain.

Assessment of a standardized EEG reactivity protocol after cardiac arrest.

OBJECTIVE: Reactivity assessment during EEG might provide important prognostic information in post-anoxic coma. It is still unclear how best to perform reactivity testing and how it might be affected by hypothermia. Our primary aim was to determine and compare the effectiveness, inter-rater reliability and prognostic value of different types of stimulus for EEG reactivity testing, using a standardized stimulation protocol and standardized definitions. Our secondary aims were to assess the effect of hypothermia on these measures, and to determine the prognostic value of a simplified sequence with the three most efficient stimuli. METHODS: Prospective single-center cohort of post-anoxic comatose patients admitted to the intensive care unit of an academic medical center between January 1, 2016 and December 31, 2018 and receiving continuous EEG monitoring (CEEG). Reactivity was assessed using standardized definitions and standardized sequence of stimuli: auditory (mild noise and loud noise), tactile (shaking), nociceptive (nostril tickling, trapezius muscle squeezing, endotracheal tube suctioning), and visual (passive eye opening). Gwet's AC1 and percent agreement (PA) were used to measure inter-rater agreement (IRA). Ability to predict favorable neurological outcome (defined as a Cerebral Performance Category of 1 to 2: no disability to moderate disability) was measured with sensitivity (Se), specificity (Sp), accuracy, and odds ratio [OR]. These were calculated for each stimulus type and at the level of the entire sequence comprising all the stimuli. RESULTS: One-hundred and fifteen patients were included and 242 EEG epochs were analyzed. Loud noise, shaking and trapezius muscle squeezing most frequently elicited EEG reactivity (42%, 38% and 38%, respectively) but were all inferior to the entire sequence, which elicited reactivity in 58% cases. The IRA for reactivity to individual stimuli varied from moderate to good (AC1:58-69%; PA:56-68%) and was the highest for loud noise (AC1:69%; PA:68%), trapezius muscle squeezing (AC1:67%; PA:65%) and passive eye opening (AC1:68%; PA:64%). Mild (odds ratio [OR]:11.0; Se:70% and Sp:86%) and loud noises (OR:27.0; Se:73% and Sp:75%), and trapezius muscle squeezing (OR:15.3; Se:76% and Sp:83%) during hypothermia had the best predictive value for favorable neurological outcome, although each was inferior to the whole sequence (OR:60.2; Se:91% and Sp:73%). A simplified sequence of loud noise, shaking and trapezius muscle squeezing had the same performance for predicting neurological outcome as the entire sequence. Hypothermia did not significantly affect the effectiveness of stimulation, but IRA was slightly better during hypothermia, for all stimuli. Similarly, the predictive value was higher during hypothermia than during normothermia. CONCLUSIONS: Despite a standardized stimulation protocol and standardized definitions, the IRA of EEG reactivity testing in post-anoxic comatose patients was only good at best (AC1 < 70%), and its predictive value for neurological outcome remained imperfect, in particular with Sp values < 90%. While no single stimulus appeared superior to others, a full sequence using all stimuli or a simplified sequence comprising loud noise, shaking and trapezius muscle squeezing had the best combination of IRA and predictive value. SIGNIFICANCE: This study stresses the necessity to use multiple stimulus types to improve the predictive value of reactivity testing in post-anoxic coma and confirms that it is not affected by hypothermia.

Ischemic Pressure vs Postisometric Relaxation for Treatment of Rhomboid Latent Myofascial Trigger Points: A Randomized, Blinded Clinical Trial.

OBJECTIVE: The purpose of this study was to investigate the effects of ischemic pressure (IP) vs postisometric relaxation (PIR) on rhomboid-muscle latent trigger points (LTrPs). METHODS: Forty-five participants with rhomboid-muscle LTrPs were randomly assigned into 3 groups and received 3 weeks of treatment-group A: IP and traditional treatment (infrared radiation, ultrasonic therapy, and transcutaneous electrical nerve stimulation); group B: PIR and traditional treatment; and group C: traditional treatment. Shoulder pain and disability, neck pain and disability, and pressure pain threshold (PPT) of 3 points on each side were measured before and after treatment. RESULTS: Multivariate analysis of variance indicated a statistically significant Group × Time interaction (P = .005). The PPT for the right lower point was increased in group A more than in groups B or C. Neck pain was reduced in group B more than in group C. Moreover, shoulder and neck disability were reduced in both groups A and B more than in group C. The PPTs of the left lower and middle points were increased in group B compared with groups A and C. The PPT of the left upper point was increased in group A more than in group C. There were significant changes in all outcomes in the 2 experimental groups (P < .05). No changes were found in the control group except in pain intensity, shoulder disability, and PPT of the left lower point. CONCLUSION: This study found that IP may be more effective than PIR regarding PPT, but both techniques showed changes in the treatment of rhomboid-muscle LTrPs.

The Effect of Scapular Muscle Strengthening on Functional Recovery in Patients With Lateral Elbow Tendinopathy: A Pilot Randomized Controlled Trial.

CONTEXT: There is a lack of consensus on the best management approach for lateral elbow tendinopathy (LET). Recently, scapular stabilizer strength impairments have been found in individuals with LET. OBJECTIVE: The purpose of this study was to compare the effectiveness of local therapy (LT) treatment to LT treatment plus a scapular muscle-strengthening (LT + SMS) program in patients diagnosed with LET. DESIGN: Prospective randomized clinical trial. SETTING: Multisite outpatient physical therapy. PATIENTS: Thirty-two individuals with LET who met the criteria were randomized to LT or LT + SMS. INTERVENTIONS: Both groups received education, a nonarticulating forearm orthosis, therapeutic exercise, manual therapy, and thermal modalities as needed. Additionally, the LT + SMS group received SMS exercises. MAIN OUTCOME MEASURE: The primary outcome measure was the patient-rated tennis elbow evaluation; secondary outcomes included global rating of change (GROC), grip strength, and periscapular muscle strength. Outcomes were reassessed at discharge, 6, and 12 months from discharge. Linear mixed-effect models were used to analyze the differences between groups over time for each outcome measure. RESULTS: The average duration of symptoms was 10.2 (16.1) months, and the average total number of visits was 8.0 (2.2) for both groups. There were no significant differences in gender, age, average visits, weight, or height between groups at baseline (P > .05). No statistical between-group differences were found for any of the outcome measures. There were significant within-group improvements in all outcome measures from baseline to all follow-up points (P < .05). CONCLUSION: The results of this pilot study suggest that both treatment approaches were equally effective in reducing pain, improving function, and increasing grip strength at discharge as well as the 6- and 12-month follow-ups. Our multimodal treatment programs were effective at reducing pain and improving function up to 1 year after treatment in a general population of individuals with LET.

Immediate Effects of Dry Needling and Myofascial Release on Local and Widespread Pressure Pain Threshold in Individuals With Active Upper Trapezius Trigger Points: A Randomized Clinical Trial.

OBJECTIVE: This study sought to compare the immediate effects of a single session of dry needling (DN), myofascial release (MR), and sham DN on pressure pain threshold (PPT) and neck pain intensity in individuals with chronic neck pain. METHODS: This was a randomized trial with a blinded outcome assessor. Forty-four individuals with chronic neck pain and unilateral myofascial trigger points in the upper trapezius muscle (UTM) were randomized to receive DN (n = 15), MR (n = 14), or sham DN (n = 15). The PPT over the UTM (ipsilateral and contralateral sides) and the proximal head of the radius (ipsilateral and contralateral to the treated side) and neck pain were assessed immediately and 10 minutes after the intervention. RESULTS: There was no significant Group × Time interaction for PPT in the UTM on the treated side (F = 0.63, P = .641) or the contralateral side (F = 1.77, P = .144). However, there was a main effect of time on both the treated side (F = 4.917, P = .001) and the contralateral side (F = 4.70, P = .015), with DN and MR increasing PPT at the UTM. No significant Group × Time × Side interaction was found for PPT at the proximal head of the radius (F = 1.23, P = .276). Within-group analysis revealed a significant increase in PPT on the ipsilateral and contralateral sides in both DN and MR. Neck pain decreased after DN (P < .001), MR (P < .001), and sham DN (P = .008). CONCLUSION: A single application of DN or MR generated local and distant hypalgesic responses superior to placebo. Future trials are needed to examine whether these findings occur in long-term follow-ups.

Interrater and Intrarater Reliability of a Handheld Myotonometer in Measuring Mechanical Properties of the Neck and Orofacial Muscles.

OBJECTIVE: The purpose this study was to investigate the reliability of a handheld myotonometer in measuring the mechanical properties of the neck and orofacial muscles in asymptomatic individuals. METHODS: The study included 16 healthy participants. The mechanical properties (frequency, decrement, stiffness, relaxation time, and creep) of the selected muscles were measured with a MyotonPRO myotonometer (Mumeetria Ltd, Tallinn, Estonia). The sternocleidomastoid, upper trapezius, cervical extensor, and masseter muscles were selected to determine the reliability of the device. Measurements were performed by 2 examiners to determine interrater reliability; for intrarater reliability, an examiner repeated the measurements 1 week after the first measurements. RESULTS: The results revealed moderate to excellent intrarater and interrater reliability (intraclass correlation coefficients: 0.50-0.95) in measuring muscle mechanic properties. The standard error of measurement in the tested muscles ranged from 0.3 to 0.8 Hz for frequency, from 7.4 to 20.9 N/m for stiffness, from 0.1 to 0.2 for decrement, and from 0.8 to 1.4 ms for relaxation time. The minimum detectable change ranged from 0.8 to 2.2 Hz for frequency, from 20.5 to 57.9 N/m for stiffness, from 0.2 to 0.6 for decrement, from 2.2 to 3.9 ms for relaxation time, and from 0.2 to 0.3 for creep. In addition, the coefficients of variation were below 9.1% for all the assessed parameters. CONCLUSION: The obtained results demonstrate that the MyotonPRO device is a reliable and repeatable tool to quantify the frequency, stiffness, decrement, relation time, and creep of the neck and orofacial muscles in asymptomatic individuals.

The Acute Effects of Manual and Instrument-Assisted Cervical Spine Manipulation on Pressure Pain Threshold, Pressure Pain Perception, and Muscle-Related Variables in Asymptomatic Subjects: A Randomized Controlled Trial.

OBJECTIVE: The purpose of this study was to compare the immediate effects in asymptomatic participants of manual and instrument-assisted cervical manipulation on pressure pain thresholds, pressure pain perception, and muscle mechanical properties (tone, stiffness, and elasticity) over muscles anatomically related and unrelated to the manipulated level. METHODS: Fifty-nine asymptomatic participants (34 women and 25 men; age [mean ± standard deviation] = 21.1 ± 1.6 years) were randomly assigned to 4 groups in a double-blind, randomized, placebo-controlled trial. Two groups received cervical (C3/C4) manipulation, 1 manual and the other instrument-assisted; the third group received a sham manipulation; and the fourth group served as the control. Bilateral pressure pain threshold, pressure pain perception, muscle tone, stiffness, and elasticity in the upper trapezius and biceps brachii were evaluated before and immediately after the interventions. RESULTS: At baseline, there were no differences among the groups on any variable. After the interventions, a significant increase in pressure pain threshold was observed with both manual and instrument-assisted manipulation at local and distal sites (P < .05), whereas no changes were observed in either the control or the placebo group. The perception of pain pressure did not change significantly in any group. The interventions did not promote any statistically significant differences in muscle tone, elasticity, or stiffness at any site (local or distal). CONCLUSION: Cervical (C3/C4) manual and instrument-assisted manipulations produced an increase in pressure pain threshold bilaterally and over muscles related and unrelated to the vertebral segment, but had no effect on muscle tone, elasticity, or stiffness.

Effects of Corrective Exercises on Posture, Pain, and Muscle Activation of Patients With Chronic Neck Pain Exposed to Anterior-Posterior Perturbation.

OBJECTIVES: This study aimed to evaluate the effects of corrective exercises on posture, pain, and muscle activation of patients with chronic neck pain exposed to anterior-posterior perturbation. METHODS: A total of 32 women (37.76 ± 3.83 years) with chronic, nonspecific neck pain were randomized into corrective exercise and control groups. The experimental group underwent a corrective exercise program for 8 weeks, 30 min/d, 3 days per week. The control group received active self-exercise instructions. Neck pain, forward head and protracted shoulder posture, and timing of superficial neck muscle activation were evaluated using the visual analog scale, photogrammetry, and electromyogram, respectively, before and then 48 hours after the 8-week program for both the experimental and control groups. All measurements at pretest and posttest were taken by a blinded assessor. RESULTS: Significant alterations were observed in cervical angle (P = .003, effect size = 0.329), shoulder angle (P = .008, effect size = 0.457), neck pain and disability (P = .009, effect size = 0.645), movement control (P = .038, effect size = 0.353), activation onset of the upper trapezius (P = .015, effect size = 0.746), the sternocleidomastoid (P = .018, effect size = 0.879) and cervical erector spinae (P = .031, effect size = 0.765), and the root mean square of the upper trapezius (P = .033, effect size = 0.742), the sternocleidomastoid (P = .041, effect size = 0.587), and the cervical erector spinae (P = .024, effect size = 0.832) in the intervention group from pre- to posttest (P < .05). CONCLUSION: Positive and significant alterations have been observed in the forward head and protracted shoulder posture, the timing of superficial neck muscle activation, neck pain, and disability in female patients with chronic neck pain exposed to anterior-posterior perturbation after performing an 8-week corrective exercise program.

The Effect of Shoulder Mobilization on Scapular and Shoulder Muscle Activity During Resisted Shoulder Abduction: A Crossover Study of Asymptomatic Individuals.

OBJECTIVE: The primary aim was to investigate the effect of inferior shoulder mobilization on scapular and shoulder muscle activity during resisted shoulder abduction in asymptomatic individuals. METHODS: This was a lab-based, repeated-measures, crossover, randomized controlled study. Twenty-two participants were recruited. The order of experimental conditions was randomized. Each participant performed 5 repetitions of resisted shoulder abduction before and after the control and mobilization (grade +IV inferior shoulder mobilization, 3 sets, 60 seconds) conditions. Surface electromyography recorded the muscle activity of anterior, middle, and posterior deltoid; supraspinatus; infraspinatus; upper and lower trapezius; serratus anterior; and latissimus dorsi muscles. RESULTS: Muscle activity levels reduced for infraspinatus (11.3% MVIC, 95% CI: 1.7-20.8), middle (22.4% MVIC, 95% CI: 15.9-28.8) and posterior deltoid (8.7 % MVIC, 95% CI: 4.6-12.9), and serratus anterior (-28.1% MVIC, 95% CI: 15.6-40.8) muscles after the mobilization condition during the eccentric phase of shoulder abduction. No carryover effects were observed, and within-session reliability was excellent (intraclass correlation coefficient scores ranging from 0.94 to 0.99). CONCLUSION: Our findings suggest that inferior glenohumeral mobilization reduces activity levels of some scapular and shoulder muscles. Given the exploratory nature of our study, changes in muscle activity levels may have been found by chance. Confirmatory studies are required.

Assessing the physiological strain of physical therapists according to work experience: A cross-sectional study.

OBJECTIVES: This cross-sectional study aimed to assess the physiological response of physical therapists to compare the physiological workload within three groups of varying work experience and their comparative physiological responses during a 15-min recovery period. METHODS: Thirty therapists participated in the present study. They were divided into three groups with varying levels of work experience based on the number of years they had been in active employment: 1) Early Career (EC) group = 2-6 years); 2) Mid-Career (MC) group = 7-11 years), and 3) Late career (LC) group = over 11 years). Each group included 10 subjects comprised of both males and females. To conduct the measurements, each therapist treated one hemiplegic patient for 20 min using a passive range of motion protocol and then rested for 15 min. The maximum voluntary contraction on trapezius and deltoid muscles were tested using electromyography before and after treatment. During treatment, the muscle workload, muscle fatigue, and cardiovascular load were measured. The perceived workload was assessed using a subjective workload index (SWI) questionnaire following treatment. RESULTS: The three work experience groups of physical therapists performed a similar workload. The SWI corresponded well with physiological measurement. The muscle capacity after treatment of the EC group was significantly lower than that of the MC group (p < 0.05). Notably, the right deltoid of the LC group was significantly lower than that of the MC group. CONCLUSIONS: The physical therapists worked with a moderate, objectified workload. A 15-min rest period brought the cardiovascular load below 30% and lowered fatigue in the right deltoids. This result may indicate a musculoskeletal disorder warning signal for the physical therapists.

Gender, BMI and side-to-side differences in spinal accessory nerve conduction from the upper and middle components of the trapezius muscle.

INTRODUCTION: There is a variety of testing methods described in the literature for the spinal accessory nerve (SAN). This study aims to evaluate side-to-side, gender, and BMI differences with surface recording from the upper and middle trapezius using a standard distance to the upper trapezius. METHODS: Subjects underwent bilateral SAN conduction testing with the active recording electrodes over the superior border of the upper trapezius, midway between the acromion and the C7 spinous process, and over the middle trapezius 3 cm medial to the vertebral border of the scapula. RESULTS: Mean latency values were 2.17 ± 0.22 msec and 3.14 ± 0.40 msec for the upper and middle trapezius, respectively. Mean amplitude values were 8.02 ± 2.2 mV for the upper trapezius and 3.96 ± 1.77 mV for the middle trapezius. The mean side-to-side latency difference was 7.8% for the upper and 9.5% for the middle trapezius, while the mean side-to-side amplitude difference was 18.2% for the upper and 37.6% for the middle trapezius. BMI had a significant inverse effect on upper and middle trapezius amplitudes such that both males and females with lower BMI had larger amplitudes. There was a significant gender difference for upper and middle trapezius latency with faster latency values observed in females. CONCLUSIONS: SAN conduction with surface recording from the upper and middle trapezius is well tolerated. Side-to-side differences may be the best way to evaluate both amplitude and latency, so bilateral testing is essential in light of anatomical variation and BMI effects on amplitude.

Interaction Between Thoracic Movement and Lumbar Spine Muscle Activation Patterns in Young Adults Asymptomatic for Low Back Pain: A Cross-Sectional Study.

OBJECTIVE: The purpose of this study was to investigate the interaction between thoracic movement and lumbar muscle co-contraction when the lumbar spine was held in a relatively neutral posture. METHODS: Thirty young adults, asymptomatic for back pain, performed 10 trials of upright standing, maximum trunk range of motion, and thoracic movement tasks while lumbar muscle activation was measured. Lumbar co-contraction was calculated, compared between tasks, and correlated to thoracic angles. RESULTS: Movement tasks typically exhibited greater co-contraction than upright standing. Co-contraction in the lumbar musculature was 67%, 45%, and 55% greater than upright standing for thoracic flex, thoracic bend, and thoracic twist, respectively. Generally, the thoracic movement task demonstrated greater co-contraction than the maximum task in the same direction. Co-contraction was also correlated to thoracic angles in each movement direction. CONCLUSION: Tasks with thoracic movement and a neutral lumbar spine posture resulted in increases in co-contraction within the lumbar musculature compared with quiet standing and maximum trunk range-of-motion tasks. Findings indicated an interaction between the 2 spine regions, suggesting that thoracic posture should be accounted for during the investigation of lumbar spine mechanics.

Influence of Forward Head Posture on Myotonometric Measurements of Superficial Neck Muscle Tone, Elasticity, and Stiffness in Asymptomatic Individuals With Sedentary Jobs.

OBJECTIVE: The objective of the study was to assess the influence of forward head posture on the mechanical parameters and pressure pain threshold of superficial neck muscles in clinically nonsymptomatic individuals with sedentary jobs. METHODS: Twenty-five office workers with forward head posture and 25 office workers with normal head posture were matched for sex, age, body mass index, and the nature and duration of their work and were compared at a single point. The study participants were divided into study groups on the basis of photometric craniovertebral angle measurements. The upper trapezius, sternocleidomastoid, and splenius capitis mechanical properties were assessed in the sitting position. Primary outcome measures were muscle stiffness (N/m), muscle tone (Hz), and muscle elasticity. The secondary variable was perceived pain threshold. RESULTS: No significant differences between the groups were found for biomechanical properties and perceived pain threshold in the studied muscles. CONCLUSION: Forward head posture has no impact on muscle stiffness, tone, and elasticity, nor does it increase the pressure sensitivity of superficial neck muscles in healthy, mildly symptomatic office workers. It is most likely that not incorrect posture of the cervical spine, but probably other factors combined with forward head posture, like comorbid acute and chronic cervical pain and musculoskeletal disorders or prolonged sitting, contribute to changes in active myofascial tone and tensegrity as well as increased pressure sensitivity of neck muscles.

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.

Comparison of muscular activities between subjects with and without scapular downward rotation impairment during diagonal pattern of exercises.

BACKGROUNDS: One form of abnormal scapular alignment is scapular downward rotation (SDR). Changes in muscle function in SDR have not been clearly identified, and SDR exercises also require investigation. Although a diagonal pattern of exercise is commonly used as part of the exercise protocol, a direct comparison of shoulder and scapular diagonal exercises has not yet been conducted. The objectives of this study were to determine the altered activation of the scapular musculature in the SDR group and to investigate which diagonal pattern of exercise effectively activates the scapular musculature. METHODS: Thirty-two participants (18 in the control group and 14 in the SDR group) volunteered to participate in this study. Electromyographic signals were collected from four muscles, the upper trapezius (UT), lower trapezius (LT), serratus anterior (SA), and anterior deltoid (AD), during standing performance of diagonal shoulder and scapular exercises. RESULTS: The control group showed significantly lower UT activity, UT/LT ratio, and UT/SA values than the SDR group (p < .05). Activation of the AD was significantly higher in the SDR than in the control group (p < .05). SA and AD activation were significantly higher in shoulder diagonal pattern exercises than in scapular diagonal pattern exercises (p < .05). The scapular posterior elevation pattern exercise showed significantly higher UT and LT activities than anterior elevation and shoulder diagonal pattern exercises (p < .05). CONCLUSION: Our findings suggest that reduced activation of the UT could lead to greater activation in the AD in SDR. Scapular posterior elevation exercise is advantageous as selectively activates the trapezius musculature, and shoulder diagonal pattern exercise is advantageous in activating the SA and AD.

The Effect of Auricular and Systemic Acupuncture on the Electromyographic Activity of the Trapezius Muscle with Trigger Points-A Pilot Study.

The purpose of this study was to analyze and compare intra and intergroup the immediate effect of the auricular and LR8 systemic acupuncture on the electromyographic activity of the trapezius with the trigger points. This is an experimental clinical trial; 40 people were split in 4 distinct groups (n = 10): GI mustard seed application in the auricular acupoint; GII bilateral needle application in the LR8 acupoint; GIII combination of the techniques; GIV/Control Group mustard seed application in an acupoint not linked to the muscle tension. The EMG was used to assess the muscle contraction for 5 seconds during the resting time and during the isometric contraction time. The EMG signal was first collect without the acupuncture intervention; then both techniques were applied for 5 minutes; and the EMG was collected again right after these applications. The Shapiro-Wilk test was used, the t test was paired with the Wilcoxon test to the intragroup comparison; One-way analysis of variance test for intergroup comparison. There was no statistical difference in the intragroup comparison for the groups. The same happened to the intergroup comparison before and after application. Systemic and auricular acupuncture did not promote immediate changes in the EMG activity of the trapezius muscle in individuals with MTrPs.

Ipsilateral EEG mu rhythm reflects the excitability of uncrossed pathways projecting to shoulder muscles.

BACKGROUND: Motor planning, imagery or execution is associated with event-related desynchronization (ERD) of mu rhythm oscillations (8-13 Hz) recordable over sensorimotor areas using electroencephalography (EEG). It was shown that motor imagery involving distal muscles, e.g. finger movements, results in contralateral ERD correlating with increased excitability of the contralateral corticospinal tract (c-CST). Following the rationale that purposefully increasing c-CST excitability might facilitate motor recovery after stroke, ERD recently became an attractive target for brain-computer interface (BCI)-based neurorehabilitation training. It was unclear, however, whether ERD would also reflect excitability of the ipsilateral corticospinal tract (i-CST) that mainly innervates proximal muscles involved in e.g. shoulder movements. Such knowledge would be important to optimize and extend ERD-based BCI neurorehabilitation protocols, e.g. to restore shoulder movements after stroke. Here we used single-pulse transcranial magnetic stimulation (TMS) targeting the ipsilateral primary motor cortex to elicit motor evoked potentials (MEPs) of the trapezius muscle. To assess whether ERD reflects excitability of the i-CST, a correlation analysis between between MEP amplitudes and ipsilateral ERD was performed. METHODS: Experiment 1 consisted of a motor execution task during which 10 healthy volunteers performed elevations of the shoulder girdle or finger pinching while a 128-channel EEG was recorded. Experiment 2 consisted of a motor imagery task during which 16 healthy volunteers imagined shoulder girdle elevations or finger pinching while an EEG was recorded; the participants simultaneously received randomly timed, single-pulse TMS to the ipsilateral primary motor cortex. The spatial pattern and amplitude of ERD and the amplitude of the agonist muscle's TMS-induced MEPs were analyzed. RESULTS: ERDs occurred bilaterally during both execution and imagery of shoulder girdle elevations, but were lateralized to the contralateral hemisphere during finger pinching. We found that trapezius MEPs increased during motor imagery of shoulder elevations and correlated with ipsilateral ERD amplitudes. CONCLUSIONS: Ipsilateral ERD during execution and imagery of shoulder girdle elevations appears to reflect the excitability of uncrossed pathways projecting to the shoulder muscles. As such, ipsilateral ERD could be used for neurofeedback training of shoulder movement, aiming at reanimation of the i-CST.

Different weight bearing push-up plus exercises with and without isometric horizontal abduction in subjects with scapular winging: A randomized trial.

The aim of the present study was to determine whether the application of isometric horizontal abduction (IHA) differentially affected two weight-bearing push-up plus exercises by examining activation of the scapulothoracic muscles in subjects with scapular winging. Fifteen male subjects performed standard push-up plus (SPP) and wall push-up plus (WPP), with and without IHA. Two-way analyses of variance using two within-subject factors were used to determine the statistical significance of observed differences in upper trapezius (UT), pectoralis major (PM), and serratus anterior (SA) muscle activities and UT/SA and PM/SA muscle activity ratios. UT and SA muscle activities were greater during SPP than WPP. PM muscle activity was lower with IHA application. The UT/SA and PM/SA muscle activity ratios were lower during SPP than WPP. The PM/SA muscle activity ratio was lower with IHA application. The results suggest that IHA application using a Thera-Band can effectively reduce PM muscle activity during SPP and WPP exercises. Moreover, the SPP exercise can be used to increase UT and SA muscle activity and reduce the UT/SA and PM/SA muscle activity ratios in subjects with scapular winging.