Shoulder Exercises Research Articles

Kinetic Chain Exercise Intervention Improved Spiking Consistency and Kinematics in Volleyball Players With Scapular Dyskinesis.

Chang, C-C, Chang, C-M, and Shih, Y-F. Kinetic chain exercise intervention improved spiking consistency and kinematics in volleyball players with Scapular Dyskinesis. J Strength Cond Res 36(10): 2844-2852, 2022-Scapular dyskinesis (SD) is a common problem among volleyball players with chronic shoulder pain. This randomized controlled study examined the effectiveness of kinetic chain (KC) training on neuromuscular performance of the scapula and trunk during volleyball spikes. Forty volleyball players with SD and chronic shoulder pain received 4 weeks of KC training or the conventional shoulder exercise training (CT). Shoulder pain was assessed using the visual analogue scale (VAS) every week. The kinematics and muscle activation of the shoulder and upper trunk, and proprioceptive feedback magnitude (PFM) for scapular movement consistency, were recorded at the maximum shoulder flexion (T1) and ball contact (T2) during spiking tasks. The two-way repeated measures analysis of variances was used to assess the between-group differences before and after the intervention. The results showed a significant time by group interaction for the upper trunk rotation ( p < 0.001) and PFM ( p = 0.03) at T2. The post-hoc test indicated that the KC group significantly increased contralateral rotation of the upper trunk (9.63 ± 4.19° vs. -4.25 ± 10.05°), and improved movement consistency (error: 8.88 ± 11.52° vs. 19.73 ± 12.79°) at T2 compared with the CT group. Significant time effects were also identified for VAS, scapular upward rotation (T1 and T2), upper trunk contralateral side-bending and PFM at T1, and upper trunk contralateral rotation at T2. In conclusion, both KC and CT training would relieve shoulder pain and improve scapular and trunk movement, whereas the KC program was more effective for increasing scapular movement consistency and upper trunk rotation during volleyball spikes.

FOREARM POSITION MATTERS DURING ECCENTRIC SHOULDER EXERCISES: AN EMG RECRUITMENT STUDY WITH IMPLICATIONS FOR REHABILITATION.

Eccentric exercise has demonstrated great utility in the rehabilitation of various shoulder pathologies. Research on the electromyographic (EMG) activity of the shoulder musculature during these activities is limited, however. Furthermore, no studies have observed how forearm positioning during exercise affects EMG output. The purpose was to examine the degree of specific muscle recruitment among commonly used eccentric exercises in rehabilitation of the upper extremity and shoulder. Secondarily, the authors hypothesized that different hand/forearm positions would alter EMG activity within the targeted musculature during a given exercise. Prospective cross-sectional observation of EMG analysis. This study analyzed surface EMG data obtained from 10 healthy individuals during five eccentric exercises of the dominant extremity, performed in a randomized order: side-lying eccentric horizontal abduction (SL ER), half-kneeling weighted ball decelerations (BALL DC), seated eccentric external rotation in scaption (STD ER), standing eccentric external rotation at 0deg (STND ER), supine eccentric external rotation at 90deg (SUP ER). Each exercise was performed with two to three forearm position variants commonly used in clinical environments: neutral, pronation, and/or supination. EMG data were collected from the upper trapezius, infraspinatus, teres minor, latissimus dorsi, and anterior/middle/posterior deltoid. Data were analyzed for each individual exercise and within each muscle using a mixed-model ANOVA repeated across forearm position. Significant interactions were followed by a Bonferroni post-hoc test for pairwise comparisons. Effect size was calculated for all significant pairwise comparisons using a Cohen's d statistic. Significant differences in EMG activity for the selected musculature exist between forearm positions for four of the five exercises and Cohen's d effect sizes 0.178 - 1.159. Specific eccentric shoulder exercises activate muscles of the shoulder complex differently based on forearm positioning. Level 2.

Strain Elastography and Tendon Response to an Exercise Program in Patients With Supraspinatus Tendinopathy: An Exploratory Study.

Background:Shoulder pain is common, with a lifetime prevalence of up to 67%. Evidence is conflicting in relation to imaging findings and pain in the shoulder. Sonoelastography can be used to estimate tissue stiffness and may be a clinically relevant technique for diagnosing and monitoring tendon healing.Purpose:To evaluate changes in supraspinatus tendon stiffness using strain elastography (SEL) and associations with changes in patient-reported outcomes, supraspinatus tendon thickness, and grade of tendinopathy after 12 weeks of unilateral shoulder exercises in patients with supraspinatus tendinopathy.Study Design:Controlled laboratory study.Methods:A total of 23 patients with unilateral clinical supraspinatus tendinopathy performed 12 weeks of “standard care” exercises. At baseline and follow-up, supraspinatus tendon stiffness was measured bilaterally using SEL and compared with tendinopathy grading on magnetic resonance imaging scans and tendon thickness measured using conventional ultrasound. Patient-reported outcome measures included physical function and symptoms from the Disabilities of the Arm, Shoulder and Hand questionnaire and pain rating (visual analog scale).Results:No significant changes in SEL within or between groups (asymptomatic vs symptomatic tendon) were seen. All patient-reported outcomes showed significant improvement from baseline to follow-up, but with no change in tendinopathy grading and tendon thickness. No significant differences in the proportion of patients changing above the minimal detectable change in SEL and PROM were seen, except for discomfort while sleeping.Conclusion:Despite no significant within-group or between-group changes in SEL, significant improvements were found in patient-reported outcomes. An acceptable agreement between patients changing above the minimal detectable change in SEL and patient-reported outcome measure was seen. Further studies should explore the use of SEL to detect changes after tendon repair and long-term training potentially in subgroups of different tendinopathy phases.Clinical Relevance:In the short term, structural changes in supraspinatus tendons could not be visualized using SEL, indicating that a longer time span should be expected in order to observe structural changes, which should be considered before return to sports. Subgrouping based on stage of tendinopathy may also be important in order to evaluate changes over time with SEL among patients with supraspinatus tendinopathy.Registration:NCT03425357 (ClinicalTrials.gov identifier).

Different Shoulder Exercises Affect the Activation of Deltoid Portions in Resistance-Trained Individuals.

The aims of this study were to compare muscle activity of the anterior deltoid, medial deltoid, and posterior deltoid in the bench press, dumbbell fly, shoulder press, and lateral raise exercises. Thirteen men experienced in strength training volunteered for the study. Muscle activation was recorded during maximum isometric voluntary contraction (MVIC) for data normalization, and during one set of 12 repetitions with the load of 60% 1RM in all exercises proposed. One-way repeated-measures ANOVA with Bonferroni’s posthoc was applied using a 5% significance level. For anterior deltoid, the shoulder press (33.3% MVIC) presented a significantly higher level of activation when compared to other exercises. Also, no significant difference was found between the bench press (21.4% MVIC), lateral raise (21.2% MVIC), and dumbbell fly (18.8% MVIC). For the medial deltoid, the lateral raise (30.3% MVIC) and shoulder press (27.9% MVIC) presented a significantly higher level of activity than the bench press (5% MVIC) and dumbbell fly (3.4% MVIC). Besides, no significant difference was found between the bench press and the dumbbell fly. For the posterior deltoid, the lateral raise (24% MVIC) presented a significantly higher level of activation when compared to other exercises. For the posterior deltoid portion, the shoulder press (11.4% MVIC) was significantly more active than the bench press (3.5% MVIC) and dumbbell fly (2.5% MVIC). Moreover, no significant difference was found between the bench press and the dumbbell fly. In conclusion, the shoulder press and lateral raise exercises showed a higher level of muscle activation in the anterior deltoid and medial deltoid when compared to the bench press and dumbbell fly exercises.

Does the Activity in Scapular Muscles During Plyometric Exercises Change When the Kinetic Chain Is Challenged?-An EMG Study.

Werin, MB, Maenhout, AG, Icket, J, Jacxsens, N, Kempkes, E, and Cools, AM. Does the activity in scapular muscles during plyometric exercises change when the kinetic chain is challenged?-An EMG study. J Strength Cond Res 36(7): 1793-1800, 2022-Plyometric exercises for the shoulder are used in rehabilitation and in workout regime when the sport demands high speed power training. The aim of this clinical laboratory electromyography (EMG) study was to determine whether scapular muscle performance differs during plyometric shoulder exercises when changing the demand on the kinetic chain. Thirty healthy overhead athletes, with a mean age of 22.7 years (±2.2), performed 6 exercises, with both a low and a high demand on the kinetic chain, in prone, side and standing in positions. The EMG activity of the upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), and serratus anterior (SA) on the tested side and bilateral of gluteus maximus (GM) and abdominal oblique externus (OE) was registered with wireless surface EMG. Intermuscular muscle ratios UT/SA, UT/MT, and UT/LT were also calculated. The level of significance set for the study was alpha = 0.05. The muscle ratio UT/SA was significantly lower (p < 0.05) when high demand on the kinetic chain compared with low. SA muscle activity showed significantly (<0.001) higher values in the prone position with high demand on the kinetic chain compared with low. All 3 trapezius muscle parts had significantly higher values (p < 0.001) in the prone compared with side and standing positions. The GM and OE showed significantly higher (p ≤ 0.01) activity in positions more demanding for the kinetic chain. When composing a strengthening or a rehabilitation program for athletes, the knowledge of how scapular and trunk muscles interact can be used to amplify the strengthening effect.

PERCEIVED SELF-REPORT OF EFFORT DURING ROTATOR CUFF & SCAPULAR REHABILITATIVE EXERCISE IN PATIENTS AFTER SHOULDER SURGERY.

Rehabilitation following shoulder surgery involves the use of resistive exercise but dosing of these -exercises historically employs multiple sets of pre-determined repetitions and few reports document the perceived effort encountered by patients during these exercises for both elastic resistance and free-weights. The OMNI-Resistance Exercise Scale (OMNI-RES) has been tested and applied as a measure of perceived exertion (RPE) for resistive exercise but has not gained widespread acceptance as an optimal method for physical therapists to document RPE during rehabilitation of shoulder surgery. To generate descriptive values of RPE encountered during common shoulder exercises of varying resistance in patients following shoulder surgery as well as provide a comparative analysis between perceived exertion ratings of similar exercise movement patterns using elastic and traditional isotonic resistance. Descriptive Cross-sectional Cohort. Sixty-six subjects (mean age 53.3 + 12.8 years) were included in this study following shoulder surgery (RC repair n=22, labral repair n=10, SA n=34). Perceived exertion using the OMNI-RES was recorded during performance of seven rotator cuff and scapular rehabilitation exercises at 6- and 12-weeks following surgery. Mean RPE using OMNI-RES in combined surgical groups ranged between 3.6 and 5.7 (mean = 4.50 + 2.1) across all seven exercises (scale 0 = very easy to 10 = extremely hard). From the external rotation (ER) exercise pair, paired t-tests revealed standing ER w/ Thera-band® (ERB) had a significantly higher OMNI-RES score versus sidelying ER w/ cuff weight (SLERW) (mean: 5.13 vs 4.41, p = 0.001) while the extension exercise pair consisting of standing shoulder extension w/ band (EXTB) and prone extension w/ cuff weight (PEXTW) showed no significant difference in OMNI-RES score (mean: 3.54, 3.67, p = 0.626). Commonly prescribed resistance exercise in the rehabilitation following shoulder surgery show light-moderate ratings of perceived exertion at both 6 & 12 week post-operative timepoints across three surgical procedures. 3b.

Strain measurement of the deep layer of the supraspinatus tendon using fresh frozen cadaver: The influence of shoulder elevation

The shoulder is a uniquely complex large joint. Effective and safe physical therapy efforts towards rehabilitating injured and repaired shoulders requires a thorough understanding of shoulder mechanics from both generalized and very specific perspectives. Numerous biomechanical studies have been published on the shoulder. None of the studies, to our knowledge, considered the strain of the deep layers of the supraspinatus tendon for scapular plane elevation. Ten unilateral fresh-frozen human cadaveric specimens were used for the study. Scapular plane angles ranging from -10 to 30 degrees were evaluated for tensile loads, ranging from 0 to 120Newtons, exerted on the supraspinatus tendon. Strain measurements that specifically targeted the deep layer of the supraspinatus tendon during tensile loading were recorded. Strains recorded in the supraspinatus deep layer while increasing tendon force of the supraspinatus were significant for isometric gleno-humeral elevation of 30° and 20°. The response of strain to tendon force was less pronounced for 10° or less of gleno-humeral elevation. When performing isometric shoulder exercise regimens, rotator cuff forces and both surface and deep tendon strain, relative to scapular positioning, are relevant and should be considered.

Shoulder amplitude movement does not influence postoperative wound complications after breast cancer surgery: a randomized clinical trial.

The goal of this study is to evaluate the influence of shoulder exercises with restricted amplitude movement (RAM) or free amplitude movement (FAM) performed from the first postoperative day (1st POD) on the incidence of surgical wound complications (SWC) in breast cancer. This study comprises a randomized clinical trial with an intention-to-treat analysis including 465 women aged 18 to 79, who underwent curative surgery for breast cancer. Participants were submitted to perform free amplitude movement (FAM) or restricted amplitude movement (RAM) shoulder exercises, until the 30th postoperative day. The outcome measures were the SWC: seroma, dehiscence, necrosis, infection, hematoma and bruise. 461 participants completed the follow-up. Thirty days after surgery, 63.8% of the women presented some surgical wound complication, with necrosis (39.3%) and seroma (30.8%) as the most frequent. No statistically significant differences in SWC according to postoperative amplitude shoulder exercise (FAM vs RAM), even after a stratified analysis by type of surgery (segmentectomy vs mastectomy) or axillary approach (axillary lymphadenectomy versus sentinel lymph node biopsy) were observed. FAM exercises do not increase the incidence of postoperative wound complications compared to RAM exercises. NCT03796845.

Optimal activation ratio of the scapular muscles in closed kinetic chain shoulder exercises: A systematic review.

Muscle synergies contribute to scapular position during arm movement. The trapezius and serratus anterior (SA) muscles are the main stabilizers and are therefore the main target muscles of therapeutic exercises. To systematically review the current literature investigating the optimal activation ratio of the scapular muscles during a range of closed kinetic chain exercises. A systematic review search was conducted to identify studies reporting shoulder electromyography (EMG) activity during rehabilitation exercises in healthy participants. The search was conducted in PubMed, Cochrane Library, MEDLINE, CINAHL, Scopus, SPORTDiscus, and ScienceDirect. The included studies reported closed kinetic chain exercises and the muscle activity as a percentage of maximum voluntary isometric contraction (%MVIC) or muscle ratios of the lower trapezius (LT), middle trapezius (MT), and SA with respect to the upper trapezius (UT). Muscle ratios were classified as optimal if they were equal to or lower than 0.6, and the adapted Newcastle-Ottawa Scale (NOS) was used to evaluate the methodological quality of the selected studies. Twenty-nine studies were included in this review; 7 main exercises and 30 variations of these were reported. The average electromyographic activity of the concentric and eccentric phase was considered. Half Push Up, Push Up Plus, and Scap Protraction exercises showed optimal SA activity (UT/SA < 0.6), while Press Up, Half Push Up, and One Hand Plank exercises showed optimal LT activity (UT/LT < 0.6). According to the NOS, 15 studies were classified as moderate methodological quality. The exercises in higher positions (e.g. exercises with the trunk closest to the vertical line) or unstable surfaces tend to favor UT activity over the MT, LT and SA. The exercises including scapular retraction showed optimal UT/MT and UT/LT ratios, while those including scapular protraction showed optimal UT/SA ratios. This will assist therapists in the correct selection of exercises for shoulder rehabilitation.

Adherence Tracking With Smart Watches for Shoulder Physiotherapy in Rotator Cuff Pathology: Protocol for a Longitudinal Cohort Study.

BackgroundPhysiotherapy is essential for the successful rehabilitation of common shoulder injuries and following shoulder surgery. Patients may receive some training and supervision for shoulder physiotherapy through private pay or private insurance, but they are typically responsible for performing most of their physiotherapy independently at home. It is unknown how often patients perform their home exercises and if these exercises are performed correctly without supervision. There are no established tools for measuring this. It is, therefore, unclear if the full benefit of shoulder physiotherapy treatments is being realized.ObjectiveThe proposed research will (1) validate a smartwatch and machine learning (ML) approach for evaluating adherence to shoulder exercise participation and technique in a clinical patient population with rotator cuff pathology; (2) quantify the rate of home physiotherapy adherence, determine the effects of adherence on recovery, and identify barriers to successful adherence; and (3) develop and pilot test an ethically conscious adherence-driven rehabilitation program that individualizes patient care based on their capacity to effectively participate in their home physiotherapy.MethodsThis research will be conducted in 2 phases. The first phase is a prospective longitudinal cohort study, involving 120 patients undergoing physiotherapy for rotator cuff pathology. Patients will be issued a smartwatch that will record 9-axis inertial sensor data while they perform physiotherapy exercises both in the clinic and in the home setting. The data collected in the clinic under supervision will be used to train and validate our ML algorithms that classify shoulder physiotherapy exercise. The validated algorithms will then be used to assess home physiotherapy adherence from the inertial data collected at home. Validated outcome measures, including the Disabilities of the Arm, Shoulder, and Hand questionnaire; Numeric Pain Rating Scale; range of motion; shoulder strength; and work status, will be collected pretreatment, monthly through treatment, and at a final follow-up of 12 months. We will then relate improvement in patient outcomes to measured physiotherapy adherence and patient baseline variables in univariate and multivariate analyses. The second phase of this research will involve the evaluation of a novel rehabilitation program in a cohort of 20 patients. The program will promote patient physiotherapy engagement via the developed technology and support adherence-driven care decisions.ResultsAs of December 2019, 71 patients were screened for enrollment in the noninterventional validation phase of this study; 65 patients met the inclusion and exclusion criteria. Of these, 46 patients consented and 19 declined to participate in the study. Only 2 patients de-enrolled from the study and data collection is ongoing for the remaining 44.ConclusionsThis study will provide new and important insights into shoulder physiotherapy adherence, the relationship between adherence and recovery, barriers to better adherence, and methods for addressing them.International Registered Report Identifier (IRRID)DERR1-10.2196/17841

Quantifying Kinematic Fidelity Of Demonstrated Therapeutic Shoulder Exercises Between Therapist And Patient

Reduced cost and greater portability of 3D motion tracking technology increases the likelihood of its use in clinical settings to evaluate therapeutic exercise quality in reference to an ideal movement pattern. It must first be determined how accurately healthy individuals can mirror a demonstrated exercise to understand the inherent variability of this approach. PURPOSE: To test the kinematic fidelity between therapeutic shoulder exercises demonstrated by a therapist and mirrored by patients. METHODS: Ten, healthy, young (21.4 ± 0.5 yr, 70.2 ± 12.3 kg, 1.68 ± 0.08 m) men and women with a history of resistance exercise training simulated the roles of therapist and patients. A physical therapy aid performed unloaded forward and lateral raise shoulder exercises while a 2D video camera and 12-camera, 3D motion capture system recorded shoulder kinematics. The 2D video recording of the therapist was played back on a life-size screen to each patient who emulated the therapist’s demonstrated exercise. Upper-body marker data of both therapist and patients were recorded at 250 Hz, smoothed with a 6 Hz low-pass filter, and shoulder joint kinematics were obtained. Custom software was used to time normalize kinematic data, obtain cross-correlations between each patients’ joint positions and the therapist’s as a global measure of agreement, calculate the mean absolute error across the range of motion, and error at peak joint excursion. Shoulder angles were compared in the sagittal plane for forward flexion and frontal plane for lateral flexion exercises. RESULTS: The mean cross-correlation coefficient for the forward raise was r = 0.98, 95% CI [0.96, 1.00], the mean error across the range of motion was 11.9 deg, 95% CI [7.8, 16.0], and error at peak excursion was 7.1 deg, 95% CI [1.6, 12.5]. The mean cross-correlation coefficient for the lateral raise was r = 0.96, 95% CI [0.95, 0.98], the mean error across the range of motion was 14.6 deg, 95% CI [11.6, 17.7], and error at peak excursion was 4.4 deg, 95% CI [0.6, 8.2]. CONCLUSIONS: After time normalization, cross-correlations revealed healthy, young people have an excellent ability to replicate the shape of demonstrated uniaxial shoulder exercises. Yet, a modest amount of absolute position error exists across the range of motion and at peak joint excursion. Supported by NSF Grant 1830597

The effectiveness of ultrasonogram guided intervention in chronic shoulder pain cases attending pain clinic of a government hospital of East zone, India: a prospective observational study

Background: Ultrasonogram guided intervention in chronic shoulder pain is well known for relief of pain and improvement of range of movement (ROM) of affected shoulder joint. Ultrasonogram gives accuracy helps in localized corticosteroid delivery. Corticosteroids relieve the pain by its anti-inflammatory effect. There is conflicting evidence available regarding the effectiveness of the intervention in chronic shoulder pain, questioned in many studies. We planned this study to evaluate the efficacy of ultrasonogram guided intervention in chronic shoulder pain in a tertiary teaching hospital of rural Bengal.Methods: The prospective observational study was carried out in 100 patients with chronic shoulder pain attending pain clinic who fulfilled predetermined inclusion criteria. Patients were injected with 40 mg of depomethyl prednisolone and 10 ml of 1% preservative free lignocaine via standard posterior approach. Then half an hour of standard shoulder range of motion (ROM) exercise regimen was performed under supervision. Pre injection and post injection pain level were scored by visual analogue score (VAS) shoulder exercises were taught and home-based physiotherapy was carried out by patients themselves. Patient were followed at 4, 8, and 12 weeks.Results: The mean age of patients was 53.23±5.680 years with 63 % male study subjects, After the intervention, excellent result in VAS score and improvement of ROM observed in patients. There was statistically significant difference from baseline in both pain relief and shoulder movement.Conclusions: USG guided intervention is effective in pain relief and in improvement in ROM in chronic shoulder pain in long term.

Effects of Dynamic Exercise Program Using Thera-Band on Craniovertebral Angle in Adults with Forward Head Posture

Background: The alignment of the neck and shoulder is important in people with forward head posture. However, previous studies have mainly conducted fragmentary studies on the neck and shoulders, and studies on the combined movement of the neck and shoulders are incomplete. Objective: To investigate the effects of 6 week dynamic exercise program using Thera-band on craniovertebral angle (CVA) in adults with forward head posture. Design: Quasi-experimental study. Methods: The study was conducted on 24 adults with forward head posture and experimented with neck and shoulder exercises and divided them into groups of neck exercises, shoulder exercises, and neck and shoulder exercises to measure CVA values before and after the experiment. The neck exercise program included flexion and extension muscles of the neck and shoulder exercises included dynamic exercise of the upper extremities such as the trapezius muscles and serratus anterior muscle. The CVA results were measured using PA200. Results: Following the interventions, neck exercise group showed significant improvement in CVA (P .05). However, both groups showed some positive results. Significant differences were seen in the comparisons between the three groups (P<.05), and the results of the posthoc test showed significant differences in neck exercise group and shoulder exercise, neck exercise and combine exercise group. Conclusion: This study suggested that the Thera-band neck exercise is beneficial for foward head posture patients and is expected to be used in clinical trials.

Neuromuscular shoulder activity during exercises with different combinations of stable and unstable weight mass

BackgroundRecent shoulder injury prevention programs have utilized resistance exercises combined with different forms of instability, with the goal of eliciting functional adaptations and thereby reducing the risk of injury. However, it is still unknown how an unstable weight mass (UWM) affects the muscular activity of the shoulder stabilizers. Aim of the study was to assess neuromuscular activity of dynamic shoulder stabilizers under four conditions of stable and UWM during three shoulder exercises. It was hypothesized that a combined condition of weight with UWM would elicit greater activation due to the increased stabilization demand.MethodsSixteen participants (7 m/9 f) were included in this cross-sectional study and prepared with an EMG-setup for the: Mm. upper/lower trapezius (U.TA/L.TA), lateral deltoid (DE), latissimus dorsi (LD), serratus anterior (SA) and pectoralis major (PE). A maximal voluntary isometric contraction test (MVIC; 5 s.) was performed on an isokinetic dynamometer. Next, internal/external rotation (In/Ex), abduction/adduction (Ab/Ad) and diagonal flexion/extension (F/E) exercises (5 reps.) were performed with four custom-made-pipes representing different exercise conditions. First, the empty-pipe (P; 0.5 kg) and then, randomly ordered, water-filled-pipe (PW; 1 kg), weight-pipe (PG; 4.5 kg) and weight + water-filled-pipe (PWG; 4.5 kg), while EMG was recorded. Raw root-mean-square values (RMS) were normalized to MVIC (%MVIC). Differences between conditions for RMS%MVIC, scapular stabilizer (SR: U.TA/L.TA; U.TA/SA) and contraction (CR: concentric/eccentric) ratios were analyzed (paired t-test; p ≤ 0.05; Bonferroni adjusted α = 0.008).ResultsPWG showed significantly greater muscle activity for all exercises and all muscles except for PE compared to P and PW. Condition PG elicited muscular activity comparable to PWG (p > 0.008) with significantly lower activation of L.TA and SA in the In/Ex rotation. The SR ratio was significantly higher in PWG compared to P and PW. No significant differences were found for the CR ratio in all exercises and for all muscles.ConclusionHigher weight generated greater muscle activation whereas an UWM raised the neuromuscular activity, increasing the stabilization demands. Especially in the In/Ex rotation, an UWM increased the RMS%MVIC and SR ratio. This might improve training effects in shoulder prevention and rehabilitation programs.

Analysis of Scapular Kinematics and Muscle Activity by Use of Fine-Wire Electrodes During Shoulder Exercises

Background: During nonoperative or postoperative rehabilitation after sports injuries, exercise selection is often based on minimal load on the injured/repaired glenohumeral structures, while optimally activating scapulothoracic muscles. Previous research explored scapular muscle activity during rehabilitation exercises using surface electromyography (EMG). However, limited information exists about the deeper lying muscle activity, measured with fine-wire electrodes, even more in combination with 3-dimensional scapular kinematics. Purpose: To report scapular kinematics synchronously with surface and fine-wire EMG during specific shoulder exercises for early rehabilitation. Study Design: Descriptive laboratory study. Methods: A total of 23 healthy male patients were recruited. Three-dimensional scapular kinematics were measured combined with EMG recording of 8 muscles during 4 commonly used shoulder exercises (inferior glide, low row, lawnmower, and robbery). Upper (UT), middle (MT), and lower (LT) trapezius and serratus anterior muscle activities were measured with bipolar surface electrodes. Intramuscular electrodes were placed in the levator scapulae (LS), rhomboid major (RM), pectoralis minor (Pm), and infraspinatus (IS) muscles. All data were normalized as a percentage of maximal voluntary isometric contraction (%MVIC). A linear mixed model with Bonferroni correction was applied for statistical analysis. Results: Scapular kinematics revealed an anterior tilt position during the inferior glide, low row, and robbery (P < .05). An upward rotation position between 20° and 30° was reached in all exercises except low row. Inferior glide (31°) and low row (42°) represented a significantly increased internal rotation position compared with lawnmower and robbery. Lawnmower and robbery showed significantly (P < .05) more MT (lawnmower, 36% MVIC; robbery, 39% MVIC) and RM (lawnmower, 59% MVIC; robbery, 66% MVIC) activation compared with inferior glide and low row. Lawnmower and robbery showed significantly (P < .05) less Pm activation (9.5%-12% MVIC). LS was significantly more active during robbery (58% MVIC) compared with inferior glide and low row (27%-36% MVIC) (P < .05). IS showed moderate activity (24%-37% MVIC) for all exercises, except low row (13% MVIC). Conclusion/Clinical Relevance: This study provides new insights about scapular positions and activation of the deeper layer muscles during 4 commonly used shoulder rehabilitation exercises. The lawnmower showed a favorable position of the scapula with less Pm activity in contrast to the low row. The inferior glide, lawnmower, and robbery should not be implemented in early phases of shoulder rehabilitation because of their moderate muscle activity.

The Relationship Between Surface Electromyographic Activity and Torque Production of the Infraspinatus Muscle in Shoulder Rehabilitation Exercises.

In current rehabilitation practice, exercise selection is commonly based on the amount of muscle recruitment demonstrated by electromyographic (EMG) analysis. A preponderance of evidence supports the concept that EMG of a muscle and torque output are positively correlated. This study was designed to investigate the relationship between surface EMG activity of the infraspinatus and torque production during exercises involving shoulder external rotation (ER). A total of 30 participants (average age = 24.6y) performed maximum voluntary isometric contraction of ER at 5 points within the range of motion of 3 shoulder exercise positions with concomitant surface EMG recording. As a maximal internally rotated position was approached, maximum ER torque and minimum or near-minimum EMG recruitment were demonstrated. Conversely, at maximally externally rotated positions, EMG activity was greatest and torque values were lowest. An inverse relationship between joint torque output and EMG activity was established in each of the 3 exercises. The inverse relationship between EMG activity and torque output during Shoulder ER suggests that there may be additional factors warranting consideration during exercise selection. Further research may be needed to determine the relative value of electrical activity versus torque output to optimize the selection of rehabilitative exercises.

Step by Step Guide to Understanding the Kinetic Chain Concept in the Overhead Athlete.

The purpose of this review will be to provide both a historical and recent review of the role of the kinetic chain for the overhead athlete. The kinetic chain concept will then be applied to clinical exercise modifications and integrations for prevention and treatment of shoulder injury. The primary conclusion reached through this review is the important role the lower extremity, trunk, and scapular region play in the development of optimal terminal segment acceleration in the overhead throwing and serving motion. Failure of any links in the kinetic chain has implications for shoulder and elbow injury in the overhead athlete. Modifications of traditional shoulder exercises emphasizing activation of the scapular stabilizers and core musculature alongside concomitant rotator cuff activation are recommended and supported in EMG research. Future research is needed to further identify risk factors and rehabilitation and prevention strategies and key clinical tests for the overhead athlete. The goal is to elucidate the important role the kinetic chain plays in both performance enhancement and injury prevention for the overhead athlete. Understanding the key role all segments of the kinetic chain play in the complex biomechanical segmental rotations required for high-level throwing and serving will assist clinicians who work with overhead athletes.

Painful Shoulder: Exercise Can Reduce Pain and Improve Mobility and Function.

Shoulder pain is common, especially as we age. Pain that limits your ability to raise your arm above your head or rotate your shoulder is called "subacromial shoulder pain." The good news is that most people with subacromial shoulder pain improve with physical therapy. A review of the most up-to-date research published in the March 2020 issue of JOSPT concluded that shoulder exercises are the best way to manage this pain. J Orthop Sports Phys Ther 2020;50(3):142. doi:10.2519/jospt.2020.0501.

Does Infiltrative Anesthesia Improve Post-operative Morbidity after Axillary Lymph Node Dissection in Patients of Breast Cancer? â A Prospective Study from a Tertiary Care Center in North India

Background: The role axillary lymph node dissection (ALND) in staging, prognostic assessment and local control in patients of breast cancer with clinically evident disease in the axilla is well established. ALND has its share of morbidity in the form of restriction of range of motion of arm, pain, paraesthesia and lymphedema influencing quality of life. This prospective study evaluates the effect of infiltrative anaesthesia injected along the nerve bundles exposed during ALND in reducing the restriction of range of motion of arm and pain scores following ALND. Methods: A total of 60 ALND in patients of operable invasive breast cancer were randomized in to two groups:- Group 1: The control group where patients of ALND were managed in the postoperative period with standard analgesia of injection acetaminophen 1 gm 8 hourly and early arm and shoulder movements from the evening of the procedure. Group 2: The test group had 5 ml of 0.125% Bupivaccaine injected each around the three nerve bundles exposed during ALND along with early arm and shoulder exercises and standard analgesia similar to the control group. Medical records of patients were analysed for age, laterality, clinical staging, histopathological parameters and surgical complications. Range of motion of ipsilateral at the shoulder and pain scores as recorded by visual analog scale (VAS) were objectively noted on day 0 to day 28 postoperatively at various intervals. Results: The range of motion at ipsilateral shoulder was measured by flexion, abduction and extension. The degrees of flexion and abduction were found to have statistically significant difference on Days 0, 3 and 7 in the test group in comparison to control group (p=0.001 for flexion on all Day 0,3 and 7 and p=0.009 for Day 0, p=0.001 for Day 3 and p<0.001 for Day 7 for abduction). Extension was better in the test group on Days 0 and 3 (p<0.001 and p=0.005 respectively). Pain scores assessed by VAS were significantly lower in test group when compared to control group on Days 0,1, 3 and 7 (p ≤ 0.01). There was no statistically significant difference in the restriction of flexion, extension and abduction and pain scores on Day 28 between the groups. Analgesia requirement was significantly reduced in the test group on days 0 and 1 (p ≤ 0.05). Conclusion: Infiltrative anaesthesia with 0.125% bupivaccaine along the nerve bundles exposed during ALND improves range of motion at shoulder and pain scores in the immediate postoperative period in patients of breast cancer.

Muscle recruitment during plyometric exercises in overhead athletes with and without shoulder pain

ObjectivesTo investigate if there is a difference in muscle activity patterns during high load plyometric shoulder exercises between overhead athletes with and without shoulder pain. DesignControlled laboratory EMG study. SettingUniversity EMG Laboratory. ParticipantsSixty overhead athletes, 30 with shoulder pain and 30 healthy controls were included. Main outcome measuresThe EMG activity of Upper Trapezius (UT), Middle Trapezius (MT), Lower Trapezius (LT), Serratus Anterior (SA), Latissimus Dorsi (LD) and Pectoralis Major (PM) on the tested side and bilateral on Abdominal Obliques Externus (OE) muscles was registered with wireless surface EMG during 3 rotational plyometric shoulder exercises in 3 positions, prone, sidelying and standing. ResultsA significant higher muscle activity was found in the shoulder pain group for MT together with an overall significant higher activity in the thoraco-humeral and abdominal muscles compared to healthy controls. ConclusionsWhen rehabilitating the overhead athlete with shoulder pain, shoulder muscles together with both thoraco-humeral and abdominal muscles need to be engaged.