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Muscle imbalances in the upper body can lead to ineffective movement patterns and potential injury. The purpose of this study was to investigate the muscle activity, impact, and muscle activation ratio of the serratus anterior (SA), upper trapezius (UT), lower trapezius (LT), and pectoralis major (PM) during the knee push-up plus (KPUP) exercise under various loads. Method: Electromyography assessed scapular muscle activity in 32 healthy adults (15 males, 17 females) during three KPUP variations. Results: PM and UT showed no significant activity differences across loads, whereas SA and LT did. SA activity was significantly higher in the weighted KPUP (WKPUP) 3 kg than that in KPUP and WKPUP 1 kg. LT activity was also significantly higher in WKPUP 3 kg compared to KPUP and WKPUP 1 kg, with KPUP showing higher activity than WKPUP 1 kg. PM/SA ratios remained consistent across loads, while UT/LT ratios varied significantly, being notably lower at 3 kg compared to 0 kg and 1 kg. Similarly, UT/SA ratios differed significantly among loads, being notably lower at 3 kg and 1 kg compared to 0 kg. Conclusion: WKPUP with 3 kg demonstrated significantly higher SA and LT activity compared to KPUP and WKPUP 1 kg. The lowest UT/LT ratio was observed during the WKPUP 3 kg, suggesting its effectiveness for optimizing muscle activation balance during KPUP exercises. These findings may inform the development of exercise protocols aimed at improving scapular stabilization. [ABSTRACT FROM AUTHOR]

Context: Decreased scapular upward rotation (UR) and diminished activation of the serratus anterior (SA) and lower trapezius (LT) are often observed among patients with subacromial impingement syndrome. Maintaining the elbow fully flexed during shoulder flexion may limit glenohumeral motion due to passive insufficiency of the triceps brachii and therefore facilitate greater scapular UR and increased scapular muscle activation. Objectives: To compare scapular UR, SA, upper trapezius (UT), middle trapezius, and LT activation levels between shoulder flexion with the elbow extended (Flexion-EE) to shoulder flexion with the elbow fully flexed (Flexion-EF). This study hypothesized that Flexion-EF would result in greater scapular UR, greater SA and LT activation, and a lower UT/SA and UT/LT activation ratio compared with Flexion-EE. Design: Cross-sectional study. Setting: A clinical biomechanics laboratory. Participants: Twenty-two healthy individuals. Main Outcome Measures: Scapular UR and electromyography signal of the SA, UT, middle trapezius, and LT, as well as UT/SA and UT/LT activation ratio were measured during Flexion-EE and Flexion-EF. Results: Flexion-EF resulted in greater scapular UR compared with Flexion-EE (P < .001). Flexion-EF resulted in greater S A activation, lower UT activation, and a lower UT/SA activation ratio compared with Flexion-EE (P< .001). Conclusions: Fully flexing the elbow during shoulder flexion leads to increased scapular UR primarily through greater activation of the SA. This exercise may be of value in circumstances involving diminished scapular UR, decreased activation of the SA, and an overly active UT such as among patients with subacromial impingement syndrome. [ABSTRACT FROM AUTHOR]

BACKGROUND: Daily activities that involve upper limb movements require muscle activation from different body parts by transferring forces and energy along the functional kinetic chain. The scapulae connect and transfer forces between the trunk and the upper limbs, so scapular dyskinesis may compromise the performance of the kinetic chain. OBJECTIVE: To assess the relationship between core muscle performance and shoulder pain and function in individuals with shoulder pain, with and without scapular dyskinesis. METHODS: Data was collected from 77 non-athlete adults aged between 18 and 50 years with shoulder pain, 45 had scapular dyskinesis. Core muscle performance was measured using the prone bridging test (PBT). Shoulder pain and disability were measured by the Shoulder Pain and Disability Index (SPADI), and the upper limbs' stability was assessed by the Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST). The peak torque of shoulder external and internal rotators was measured using an isokinetic dynamometer. Multiple linear regression models evaluated the relationship between the PBT and CKCUEST, SPADI, and shoulder rotator strength. RESULTS: Significant correlations were found between the PBT and the SPADI total score (r = – 0.522), pain domain (r = – 0.513), and disability domain (r = – 0.501); normalized score (r = 0.593), and the power (r = 0.624) of the CKCUEST; and peak torque for external (r = 0.256) and internal (r = 0.292) rotations. Scapular dyskinesis did not influence the magnitude of the correlations and predictive values. CONCLUSION: The PBT was correlated with shoulder pain and function, but scapular dyskinesis did not affect the magnitude of these relationships. [ABSTRACT FROM AUTHOR]

Background: Shoulder injuries are substantial problems in overhead athletes, and more studies are necessary to deepen the knowledge on this type of injury. The objective of this study was to compare the overall function and performance of female overhead athletes with and without a previous history of shoulder injuries. Methods: In this cross-sectional study, female overhead athletes with and without a previous shoulder injury were included. Muscular impairment, the stability of the shoulder, strength, scapular dyskinesia, functionality and sports performance were evaluated. A total of 50 females were included. Results: There were significant differences in strength (p = 0.046) and stability (p = 0.039) between groups, with a poorer score in the group with a history of shoulder injury. Regarding scapular dyskinesia, significant differences were also observed between groups (p = 0.048), with higher levels of dyskinesia in the group with previous shoulder injury. Also, muscular impairment showed significant differences between groups for the three muscles evaluated (p < 0.005). Additionally, the group without a previous shoulder injury presented with a significantly greater score in functionality (p = 0.046) and sports performance (p = 0.004). Conclusion: In conclusion, previous shoulder injuries are an important factor to take into account in female overhead athletes. Players with a history of shoulder injury present clinical impairments during the game, leading to poorer functional status and performance in sport. [ABSTRACT FROM AUTHOR]

Aims Scapula dyskinesis and reduced strength of the glenohumeral external rotator muscles are shoulder risk factors. The shoulder joint’s unstabilizing mechanisms can cause a decrease in the strength of the external rotator muscles, an imbalance of the rotator cuff muscles, and scapula dyskinesis. This study aimed to investigate the effect of an exercise program on scapula dyskinesis and the strength of glenohumeral rotator cuff muscles in overhead athletes. Materials & Methods The present quasi-experimental study with a control group and preand post-test plan was conducted on 62 female handball players (club-level, 18-25 years old) with scapula dyskinesis from 2021 to 2022 in Hamadan City, Iran. The lateral scapular slide test and hand dynamometers were used to measure scapula dyskinesis and the strength of glenohumeral rotator cuff muscles, respectively. The participants in the intervention group participated in eight weeks of three sessions of an exercise program. Data were measured before and after the intervention and were analyzed using the Mann-Whitney U test. Findings According to this test, there is a significant difference between the strength of external rotator muscles (p<0.001) in the intervention and control groups after exercises, so the strength of external rotator muscles and the strength of external/internal rotator muscles ratio (p<0.001) has increased after exercises. Also, scapula dyskinesis after exercises has decreased significantly (p=0.013). Conclusion The exercise program increases the strength of external rotator muscles and the ratio of external/internal rotator muscles and improves scapula dyskinesis in overhead athletes. [ABSTRACT FROM AUTHOR]

Subacromial impingement syndrome (SIS) is one of the most common causes of shoulder pain in adults and is caused by muscle imbalance around the shoulder joint, which is referred to as secondary SIS. Centralization of the glenohumeral joint (CGH), one of the intervention methods for this, targets strengthening the control ability of the rotator cuff. Dynamic humeral centering (DHC) targets the learning of selective contractile function of the pectoralis major and latissimus dorsi as depressors of the humeral head. This study aims to determine the short-term effects of CGH and DHC on pain, disability, and grip strength in patients with secondary SIS. Forty-eight patients with secondary SIS participated in the study and were randomly allocated into three groups (CGH group (n = 16), DHC group (n = 16), and simple exercise group (n = 16)) and received the intervention for 50 min. The Constant–Murley score was used to assess shoulder pain and disability (primary outcome), and a hand-held dynamometer was used to assess grip strength (secondary outcome). Measurements were performed before the intervention and one day after the intervention. The results showed that the Constant–Murley score improved in the CGH and DHC groups. In addition, pain and disability (range of motion scores) improved in both the CGH and DHC groups. Improvements in disability (shoulder strength) and grip strength were seen only in the CGH group. Both CGH and DHC can be used as methods for short-term pain release and disability recovery in secondary SIS. In particular, CGH appears to be more effective in the short-term improvement in shoulder strength and grip strength. [ABSTRACT FROM AUTHOR]

To investigate whether scapular movement training (SMT) is superior to standardized exercises in improving scapular biomechanics, behavioral, and clinical aspects of individuals with shoulder pain. A total of 64 individuals with chronic shoulder pain were randomly assigned to receive 16 sessions of SMT or SE over 8 weeks. Outcome measures included three-dimensional scapular kinematics, muscle activity of scapulothoracic muscles, pain, disability, fear-avoidance, kinesiophobia, and self-perceived changes. Kinematics and muscle activity were assessed at baseline and after treatment, and self-reported measurements at baseline, 4, 8, and 12 weeks. SMT significantly (p < 0.05) decreased scapular internal rotation during arm elevation and lowering at sagittal and scapular planes (mean difference [MD]: ranged from 2.8 to 4.1°), and at lower angles of arm elevation and lowering at the frontal plane (MD: 3.4° and 2.4°, respectively), increased upper trapezius (UT) activity (MD: 10.3%) and decreased middle trapezius (MT) (MD: 60.4%) and serratus anterior (MD: 9.9%) activity during arm lowering compared to SE. Both groups significantly improved pain, disability, fear-avoidance, kinesiophobia, and self-perceived changes over 4 weeks, which was sustained over the remaining 8 weeks. SMT is not superior to standardized exercises in improving scapular biomechanics, behavioral, and clinical aspects of individuals with shoulder pain. NCT03528499 Scapular movement training (SMT) showed small and likely not clinically relevant changes in scapular kinematics and muscle activity compared to standardized exercises. SMT and standardized exercises presented similar improvements in pain, disability, fear-avoidance beliefs, kinesiophobia, and self-perceived change in health condition immediately following 4-weeks of treatment, which was sustained over the following 8 weeks. The changes in patient-reported outcome measures are unlikely to be associated with changes in scapular kinematics and electromyographic activity. Clinicians should consider other factors than scapular movement during the treatment of patients with shoulder pain. [ABSTRACT FROM AUTHOR]

Comparing short- and long-term effects of comprehensive physiotherapy (CP) and subacromial corticosteroid injection (SCI) on pain, disability, and quality of life in the patients with subacromial pain syndrome (SAPS). 2 × 4 randomized controlled trial. 50 participants with unilateral SAPS. Random assignment with allocation concealment into two groups labeled as 12 sessions, supervised CP (n = 22) and 1cc triamhexal SCI (n = 25). Visual Analog Scale (VAS), Shoulder Pain and Disability Index (SPADI), shortened Disabilities of Arm, Shoulder and Hand (Quick-DASH), and Western Ontario Rotator Cuff Index (WORC). Outcomes were gathered pre- and post-intervention, with three- and six-month follow-ups. Variance analysis revealed that there was a significant interaction of group-in-time for SPADI and WORC (P <.05) but not for Quick-DASH and VAS (P >.05). The independent t-test analysis showed that the mean scores of all outcome measures in CP group were lesser than SCI group via 6 months (P <.05), except for the VAS (P >.05, mean difference = −0.97, 95% confidence interval −2.11–0.15). CP results in statistically significant and potentially clinically important difference in function and quality of the life at all timeframe. Moreover, there was no between group difference in order to reduce pain. [ABSTRACT FROM AUTHOR]

BACKGROUND: While positive short-term effects from corrective exercise on neck-shoulder pain (NSP) are evident, maintenance effects after cessation of the exercise remain unknown. OBJECTIVE: The objective of the present study was to assess the lasting effects of corrective exercise in NSP and workability after a year of detraining. METHODS: A cohort study with 1-year follow-up was carried out in two previous training groups (n = 24) using a self-reported paper-based questionnaire, which was completed three times (baseline, 8-week exercise, and 1-year detraining). The subjects (mean±SD age: 39.0±6.4, 38.1±8.0) responded to the Visual Analogue Scale (VAS) for NSP as the primary outcome. A single validated item from the Workability Index determined workability as the secondary outcome. Between and within-group differences of the two groups were investigated using non-parametric tests, including 12 subjects in each group. RESULTS: The results indicated that 8-week exercise improvements in NSP and mental and physical workability were largely maintained after one year of detraining. The lasting effects of NSP and physical and mental workability were statistically identified in 8-week and 1-year follow-ups. Nevertheless, it is noticeably warranted to adhere to the exercise program. CONCLUSION: The current study indicates that a brief 8-week exercise period once per year is sufficient to reduce pain and improve workability among workers. This knowledge can make exercise interventions more feasible and cost-effective for companies aiming to improve employee health. [ABSTRACT FROM AUTHOR]

Introduction: Overhead movement demands optimal pelvic and scapular stability and alignment for efficient energy transfer during shoulder movements. Throughout a sports game, hyperactivity of the pelvic and scapular musculature might affect performance. As a result, we can establish goals for muscle strength and injury prevention. To study the muscles activation of posterior oblique sling muscles (POS) in different hip positions (Standing, Sitting and Lunge) with three different shoulder movements (flexion, extension & abduction) among a sportsman population. Material and methods: Muscle activation was recorded by surface electromyography in 38 male athletes of different sports cricket (bowlers)-10; baseball-9; volleyball-9; control group (recreational overhead)-10. Maximum voluntary isometric contraction (MVIC) measurements were collected in order to compare muscular activation. Every player performed shoulder flexion, abduction and extension in standing, sitting and lunge positions. Results: Significant differences in muscle activity were noted using a 3-way ANOVA and Bonferroni post hoc test. The results of the study showed statistically significant interactions between individual groups, positions and muscles with shoulder movements (p = 0.001) and a pairwise comparison between subjects showed a significant difference (p = <0.05). Conclusions: All hip position changes may be beneficial in scapular rehabilitation training because more muscles are employed. However, in shoulder extension motions, posterior oblique sling muscles are activated more than abduction muscles. While sitting, the serratus anterior is the most active muscle, more than the lower trapezius, latissimus dorsi, and gluteus maximus. [ABSTRACT FROM AUTHOR]

Background: Improvements in motor control of the scapular muscles are important for the prevention and rehabilitation of shoulder and elbow injuries in overhead athletes. Purpose: To clarify scapular muscle activity during multijoint compound movement exercises using fine-wire and surface electrodes. Study Design: Descriptive laboratory study. Methods: Sixteen healthy men performed 5 types of exercises (cat and dog, trunk rotation, A-exercise, T-exercise, and Y-exercise). Muscle activity was measured as percentage of maximum voluntary isometric contraction (%MVIC) by using fine-wire electrodes in the rhomboid major (Rhom) and using surface electrodes in the upper (UT), middle (MT), and lower (LT) trapezius and serratus anterior (SA) muscles. The Rhom/UT, MT/UT, LT/UT, and SA/UT muscle activity ratios were calculated. One-way analysis of variance was used to compare the %MVIC and muscle activity ratios between exercises. Results: There was no significant difference in Rhom activity between the exercises (34.6-54.2%MVIC; P =.25). LT activity was significantly greater in the trunk rotation (58.0 ± 24.6%MVIC) and Y-exercise (63.2 ± 40.1%MVIC) than in the cat and dog scapular retraction (19.6 ± 9.3%MVIC) and A-exercise (28.2 ± 14.2%MVIC) (P <.05). SA activity was significantly greater in the cat and dog scapular protraction (26.7 ± 11.0%MVIC) and Y-exercise (25.6 ± 19.3%MVIC) than in the other exercises (P <.05). The SA/UT activity ratio in the cat and dog scapular protraction exercise (9.64 ± 8.48) was significantly higher than in the other exercises (P <.05). Conclusion: All the exercises were effective for activating the Rhom. The trunk rotation and Y-exercise were effective for activating the LT, and the cat and dog scapular protraction exercise was effective for activating the SA while suppressing the UT. Clinical Relevance: These results enable exercise selection based on muscle activity characteristics (moderate [20%-50%MVIC] and high [>50%MVIC] levels contribute to muscle activation) to prevent and rehabilitate shoulder and elbow injuries. [ABSTRACT FROM AUTHOR]

The wall-slide exercise is commonly used in clinic and research settings. Theraband positioning variations for hip exercises have been investigated and used, but Theraband positioning variations for upper extremity wall-slide exercises, although not commonly used, have not been examined. To evaluate the effect of different Theraband positions (elbow and wrist) on the activation of the scapular and shoulder muscles in wall-slide exercises and compare these variations with each other and with regular wall-slide exercises for the upper limbs. Descriptive laboratory study. University laboratory. A total of 20 participants (age = 23.8 ± 3 years, height = 176.5 ± 8.14 cm, mass = 75.3 ± 12.03 kg, body mass index = 24.23 ± 4.03) with healthy shoulders. Participants performed wall-slide exercises (regular and 2 variations: Theraband at the elbow and Theraband at the wrist) in randomized order. Surface electromyographic activity of the trapezius (upper trapezius [UT], middle trapezius [MT], and lower trapezius [LT]), infraspinatus, middle deltoid (MD), and serratus anterior (SA) muscles. Regular wall-slide exercises elicited low activity in the MD and moderate activity in the SA muscles (32% of maximal voluntary isometric contraction [MVIC] in the SA), whereas the Theraband-at-elbow and Theraband-at-wrist variations elicited low activity in the MT, LT, infraspinatus, and MD muscles and moderate activity in the SA muscle (46% and 34% of MVIC in the SA, respectively). The UT activation was absent to minimal (classified as 0% to 15% of MVIC) in all wall-slide exercise variations. The Theraband-at-wrist variation produced lower UT:MT, UT:LT, and UT:SA levels compared with the regular wall-slide exercise and Theraband-at-elbow variation. In shoulder rehabilitation, clinicians desiring to activate the scapular stabilization muscles should consider using the Theraband-at-wrist variation. Those seeking more shoulder-abduction activation and less scapular stabilization should consider using the Theraband-at-elbow variation of the upper extremity wall-slide exercise. [ABSTRACT FROM AUTHOR]

Introduction: Shoulder impingement syndrome (SIS), characterized by decreased acromiohumeral distance (AHD), is a promising objective outcome measure with both clinical and research utility. The purpose of this study was to evaluate and compare the effectiveness of combining exercise therapy and manual therapy with motor control exercise on AHD in overhead athletes with SIS. Material and methods: Ten overhead athletes with clinically diagnosed SIS were randomly assigned to two groups. The exercise therapy plus manual therapy (ET plus MT) group received the exercise therapy plus manual therapy regime, and the motor control exercises (MCE) group followed the motor control exercise protocol. Both groups underwent eight weeks of intervention, and AHD was evaluated at three levels of abduction (0°, 45°, 60°) with real-time ultrasound. The AHD evaluation was performed at baseline and at end of intervention (week 8). Results: AHD improvement was noted at all three levels only in the ET plus MT group and the mean difference was found to be 2.62 ± 0.18 mm (0°), 3.28 ± 0.40 mm (45°) and 3.77 ± 0.30 mm (60°). Statistical analysis performed with two-way repeated measures ANOVA (3 × 2) revealed significant group effects for AHD (0°: F (2,1.10) = 0.76, p < 0.001; 45°: F (2,0.98) = 0.80, p < 0.001; 60°: F (2,0.95) = 0.84, p < 0.001). Time effect and interaction effects were also found to be significant. Conclusions: ET plus MT appears to be a more effective rehabilitation tool than MCE since it improves AHD at 0°,45°, 60° in overhead athletes with SIS. [ABSTRACT FROM AUTHOR]