Glenohumeral Internal Rotation Deficit Research Articles

Soft Tissue Glenohumeral Internal Rotation Deficit Revealed Detailed Musculoskeletal Factors of Baseball Players.

Weng, Y-H, Huang, T-S, Chang, C-Y, Yang, J-L, Chen, W-S, and Lin, J-J. Soft tissue glenohumeral internal rotation deficit revealed detailed musculoskeletal factors of baseball players. J Strength Cond Res XX(X): 000-000, 2024-Glenohumeral internal rotation deficit (GIRD) remains contentious regarding its role in shoulder injuries. Soft tissue GIRD (ST-GIRD), reflecting soft tissue changes, may offer a more precise understanding of the injury mechanism. This study investigates correlations between ST-GIRD, self-perceived function/performance, and musculoskeletal factors in baseball players, comparing them with traditional GIRD measurements. Subjects completed the Kerlan-Jobe Orthopedic Clinic self-report questionnaire for function and performance. Soft tissue GIRD, adjusted for humeral retrotorsion, was calculated. Eighty baseball players from various levels were recruited. Kerlan-Jobe Orthopedic Clinic scores significantly correlated with ST-GIRD (r = 0.307, p = 0.046) but not with GIRD (r = 0.164, p = 0.161). Soft tissue GIRD significantly correlated with scapula root of spine alignment (r = -0.303, p = 0.023) but not with GIRD (r = -0.069, p = 0.614). Higher correlation coefficients were found between acromiohumeral distance and posterior capsule thickness with ST-GIRD (r = -0.241 and 0.236, respectively) than with GIRD (r = 0.183 and 0.122, respectively). Soft tissue GIRD offers more detailed musculoskeletal insights than GIRD, showing improved correlations with function/performance, scapular alignment, acromiohumeral distance, and posterior capsule thickness. This supports the notion that internal rotation deficiency is associated with increased posterior capsule thickness and decreased acromiohumeral distance. These results provide coaches and health care practitioners a more detailed way to monitor function and performance of baseball players.

Is Stretching Effective for Reducing Glenohumeral Internal Rotation Deficit? A Systematic Review and Meta-Analysis

Is Stretching Effective for Reducing Glenohumeral Internal Rotation Deficit? A Systematic Review and Meta-Analysis

The Role of Humeral Torsion on Glenohumeral Rotation in Injured Baseball Players.

Differences in rotational range of motion (ROM) compared to humeral retrotorsion (HRT)-corrected rotational ROM exist in healthy baseball athletes, but it is unclear whether these differences exist in a pathological population. The purpose of this study was to determine if there are disparities between objectively measured differences in ROM and HRT-corrected deficits in injured baseball players. It was hypothesized that disparities would exist between (1) the side-to-side difference in glenohumeral external rotation (GER) and the HRT-corrected glenohumeral external rotation deficit (GERD) and (2) the side-to-side difference in glenohumeral internal rotation (GIR) and the HRT-corrected glenohumeral internal rotation deficit (GIRD). Cross-sectional study; Level of evidence, 3. Data from 172 baseball players with shoulder or elbow injuries (45 shoulder, 127 elbow) were reviewed in July 2023. GER and GIR were measured on the injured and noninjured sides of all players, and diagnostic ultrasound was used to measure HRT. Dependent t tests were run to compare the side-to side differences in GER and GIR with the HRT-corrected GERD and GIRD, respectively. In the players with a shoulder injury, there was a significant disparity between the side-to-side difference in GER and the HRT-corrected GERD (2°± 14° vs -13°± 15°, respectively) and between the side-to-side difference in GIR and the HRT-corrected GIRD (-14°± 8° vs 2°± 9°, respectively) (P < .001 for both). Similarly, players with an elbow injury had significant disparities between the side-to-side difference in GER and the HRT-corrected GERD (6°± 9° vs -10°± 9°, respectively) and between the side-to-side difference in GIR and the HRT-corrected GIRD (-12°± 8° vs 4°± 10°, respectively) (P < .001 for both). The results supported our hypothesis that there were disparities between objectively measured differences in GER and GIR compared with the HRT-corrected GERD and GIRD in injured baseball players. Consideration must be given to osseous adaptations that occur at the glenohumeral joint when evaluating and treating this population.

Increased Humeral Retrotorsion is not a Risk Factor for Overuse Injury of the Throwing Shoulder in Elite Youth Handball Athletes

PurposeTo identify the potential role of humeral retrotorsion (HRT) and range of motion (ROM) as a risk factor for shoulder overuse injury in elite youth handball players. The hypothesis was that increased HRT is associated with an increased risk of shoulder overuse injury. MethodsOver two seasons, 258 elite youth handball players (52% boys; age:14±0.8years) were included. Pre-season assessment included HRT and glenohumeral internal (IR) and external (ER) rotational ROM using ultrasound and a manual goniometer. Sports-specific adaptations between male and female athletes and the dominant and nondominant shoulder were calculated. In addition, players completed standardized questionnaires over the 2018-2019 or 2019-20 season and reported any shoulder overuse symptoms using the Western Ontario Shoulder Index questionnaire. ResultsComparing male and female players showed significantly decreased HRT and decreased internal ROM in the dominant side of male athletes (p≤0.027). No other difference was found. Significant side-to-side differences between the dominant and non-dominant shoulder were found for HRT, IR, and ER, regardless of sex (p<0.001). For total range of motion (TROM), only female athletes showed a significant increase in the dominant arm (p=0.032). The dominant side showed a significantly higher glenohumeral internal rotation deficit (GIRD) in male athletes than in female athletes (10°±17° vs. 5°±10°, p=0.011). Adaptations in HRT, ER gain, and TROM gain were not significant. Over the course of the two seasons, 20 athletes reported shoulder overuse injuries. Although GIRD was borderline non-significant (p=0.056), none of the parameters tested were significantly associated with shoulder overuse injuries. ConclusionDespite significant side-to-side differences and sport-specific adaptations, individual pre-season screening of humeral retrotorsion and soft tissue adaptations does not identify elite youth handball athletes at increased risk of shoulder overuse injury.

Trunk and shoulder strength and mobility in young female volleyball and handball athletes

IntroductionVolleyball and handball have typical overhead throwing motion that can generate adaptations in the athlete's kinetic chain predisposing to injuries and pain. Considering the importance of the trunk and shoulder in overhead throwing motion and the particularities of these action in different sports, this study aimed to compare the trunk and shoulder muscle strength and mobility in young female volleyball and handball athletes. DesignCross-sectional study with 70 female volleyball and handball athletes between 13 and 18 years old. MethodsShoulder rotators, trunk extension and flexion with rotation strength was measured with a handheld dynamometer (MicroFET 2, Hoogan Health Industries, West Jordan, UT, USA). Shoulder and trunk range of motion was measured with a digital inclinometer (Acummar – model ACU001). Total range of motion deficit (TROM deficit), glenohumeral internal and external rotation of dominant (DOM) and non-dominant (NDOM) shoulder were also calculated. ResultsHandball athletes presented greater muscle strength of trunk flexors/rotators (DOM: 24.96%, effect size: 0.687; NDOM, 31.83%, effect size: 0.798) and dominant shoulder internal rotators (16.65%, effect size: 0.619). The groups showed no difference for trunk and shoulder range of motion and external rotators strength. A TROM (volleyball: 48%, handball: 35%) and a glenohumeral internal rotation deficit (volleyball: 28%, handball: 29%) was found in both groups. ConclusionsYoung female handball athletes have greater strength of trunk flexors/rotators and dominant shoulder internal rotators compared to volleyball athletes. These differences may be related to the different demands required in the movement of these sports.

Glenohumeral Internal Rotation Deficit in Young Asymptomatic Elite Swimmers.

Glenohumeral internal rotation deficit (GIRD) may affect overhead athletes and contribute to shoulder injury. To assess data on passive shoulder range of motion (ROM) in young elite swimmers and to determine the prevalence of anatomical and pure GIRD (aGIRD and pGIRD, respectively) in a large sample size of asymptomatic elite swimmers with a new classification method. Cross-sectional study. Research laboratory. A total of 752 asymptomatic elite swimmers were recruited by voluntary participation (391 males and 361 females; mean age, 15.88 ± 2.31 years). Passive glenohumeral rotational ROM was measured bilaterally to investigate the prevalence of aGIRD and pGIRD. Evaluations were performed with athletes at rest before any training or competition. Glenohumeral internal rotation deficit and associated aGIRD and pGIRD in elite youth swimmers by identifying a standard classification procedure. Glenohumeral internal rotation deficits were found in 136 participants (18.1%). Anatomical GIRD was present in 28 cases (3.7%), whereas pGIRD was observed in 108 cases (14.4%). No significant differences were found regarding GIRD between sex, age, age group, years of training, breathing side, and distance. Swimmers with pGIRD showed significantly less dominant internal rotation, total ROM, and external rotation gain (P < .01) than swimmers with aGIRD; conversely, swimmers with aGIRD showed significantly less nondominant internal rotation, external rotation, and total ROM than swimmers with pGIRD (P < .01). Glenohumeral internal rotation deficit is a relatively common condition in asymptomatic elite youth swimmers; as to not overestimate this condition, aGIRD and pGIRD have to be distinguished. Although they play a role, the respiratory side, dominant limb, and crawl did not have a significant impact on an elite swimmer with GIRD.

Risk factors for shoulder injury in professional male handball players: A systematic review

Handball is a globally popular and physically demanding sport that requires high-intensity intermittent activities, with a particular emphasis on frequent ball throwing or shooting. The primary aim of this systematic review was to identify the risk factors for shoulder injuries in professional male handball players. The secondary aim is to propose preventive measures for reducing shoulder injuries in professional or elite handball players. This study followed the guidelines provided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Web of Science, PubMed, Science Direct, and Google Scholar were used to identify relevant studies. Only 8 studies met the eligibility requirements and were incorporated into the review. The Physiotherapy Evidence Database (PEDro) was assessed for the methodological quality of studies. Seven of the total eight studies were considered moderate quality, however, only one study was considered low quality. Based on this review findings, the following risk factors for shoulder injury are prominent among professional and elite male handball players. The primary factors for eventual shoulder injury are shoulder muscle imbalances, range of motion (ROM) discrepancies, glenohumeral internal rotation deficit (GIRD), and scapular dyskinesis. Also, in one study authors specified player position as a potential risk factor.

Shoulder External Over Internal Rotation Ratio Is Related to Biomechanics in Collegiate Baseball Pitching.

Altering baseball pitching mechanics affects both performance and the risk of injury. The purpose of this study is to investigate the relationships of shoulder external over internal rotation ratio (SEIR) and other shoulder rotational properties during physical exam and biomechanics of pitching for 177 collegiate baseball pitchers. The shoulder range of motion was quantitatively measured using a custom-made wireless device. Pitching motion data were collected at 240Hz, and a custom program was created to calculate the throwing arm motion and loading during baseball pitching. Linear regression and analysis of variance tests were performed to investigate the relationships between the shoulder physical exam outcomes and throwing arm biomechanics. SEIR had significant correlations with shoulder horizontal adduction angle at foot contact, maximum shoulder external rotation angle, maximum shoulder linear velocity, and elbow angle at ball release. SEIR groups had significant differences in shoulder proximal force, adduction torque, internal rotation torque, and horizontal adduction torque, and in elbow medial force and varus torque. Glenohumeral internal rotation deficit and total rotational motion deficit had no relationships with throwing arm motions or joint loadings. Shoulder health should be monitored to improve understanding of pitching mechanics in collegiate baseball pitchers.

Comparison of Muscle Energy Technique, Myofascial Release, and Combined Techniques for Glenohumeral Internal-Rotation Deficit. An Interventional Study

Comparison of Muscle Energy Technique, Myofascial Release, and Combined Techniques for Glenohumeral Internal-Rotation Deficit. An Interventional Study

Glenohumeral internal rotation deficit: insights into pathologic, clinical, diagnostic, and therapeutic characteristics.

Overhead athletes undergo significant biomechanical adaptations due to repetitive overhead movements, primarily affecting the glenohumeral joint. These adaptations can lead to glenohumeral internal rotation deficit (GIRD), which is characterized by posterior capsule stiffness that results in glenohumeral joint translation and a shift in the center of gravity. The severity of GIRD is dependent upon the presence of asymmetry between gained external and lost internal rotation, which is defined clinically as an asymmetry exceeding 20º; this reduces the total range of motion compared to the unaffected limb or baseline measurements. Diagnosis is challenging, as it can be mistaken for chronic scapular adaptations. To mitigate misdiagnosis, a high clinical suspicion is crucial in overhead athletes, especially those who began performing forceful overhead movements before closure of growth plates. Periodic physical examinations should establish baseline values for glenohumeral rotation and track changes in glenohumeral motion to aid in diagnosis. Symptoms of GIRD include shoulder pain, stiffness, and decreased force exertion. Magnetic resonance imaging is the preferred imaging method for evaluating GIRD and assessing concomitant soft tissue pathologies. Untreated GIRD can lead to rotator cuff strength imbalances. Treatment mainly involves conservative measures, such as physical therapy, to improve internal rotation and alleviate posterior tightness. Surgical interventions are considered when symptoms persist despite conservative treatment with physical therapy or in the presence of concomitant pathologies.

Prevalence of Glenohumeral Internal Rotation Deficit in Fast Bowlers and Its Correlation with Bowling Speed

Prevalence of Glenohumeral Internal Rotation Deficit in Fast Bowlers and Its Correlation with Bowling Speed

Analysis of the functional performance of the shoulder in swimming athletes with and without a history of injury

Background: Swimmers have a significant potential for shoulder injuries due to the unique nature of the different styles involved in swimming, as well as the high volume of repetitions required during training, which arise through repetitive strain and microtrauma. Injuries are the most frequent due to the repetitive use of the upper limb in overhead movements and factors related to Range of Motion (ROM) and strength. Objective: To analyze the performance of the shoulder of swimming athletes and to verify if there is a difference between athletes with and without a history of injury, as well as to verify the transmission between the performance of this joint with ROM and strength values. Methods: 24 competitive swimmers were evaluated, with an average age of 20 years (± 7.9). The glenohumeral internal rotation deficit (GIRD) and internal and external rotation ROM of the shoulder were evaluated using goniometry. Shoulder functionality was assessed using the closed kinetic chain test for upper limbs (CKCUEST). Handgrip strength was also evaluated with a dynamometer. SPSS software, version 21.0, was used and data were analyzed using Pearson's collaboration test and Student's t test for independent samples. Results: Athletes with a history of injuries had a higher weekly training load, although they did not differ in terms of the number of years practicing the sport. The performance in the CKCUEST was higher in the group without a history of injury (p=0.04) and there was no difference between the groups regarding the variables of total ROM and GIRD, as well as for grip strength. There was change only between the CKCUEST power values with the grip strength (p&lt;0.05, r=0.677). Conclusion: The functional performance of the shoulder is greater in athletes without a history of injury.

Risk of injury and kinematic assessment of the shoulder biomechanics during strokes in padel players: a cross-sectional study.

Padel players commonly suffer from shoulder pain and the particularly high incidence is probably linked to the high frequency of strokes. In addition, due to the repetitive technical gesture, an adequate technique is essential in terms of performance and injury risk prevention. Aim of this study was to objectively evaluate shoulder kinematic during the athletic gesture to analyze the risk factors linked to padel strokes. Professional and amateur padel players underwent a three-dimensional motion analysis of the padel strokes utilizing optoelectronic and surface electromyography systems (BTS Bioengineering, Garbagnate Milanese, Milan, Italy). Twelve padel players were included in this study (10 professional players in Group A and 10 amateurs in Group B). Experience influences the execution of padel strokes with a significant difference between group A and B in terms of gleno-humeral rotation and scapular tilt. Moreover, a subgroup analysis revealed that male players execute voleè with a higher external rotation (P=0.043), and forehand with a higher scapular tilt (P=0.044). The results confirm that the high ranges of motion of the overhead strokes could rise the risk of slap lesion, impingement, and glenohumeral internal rotation deficit. However, a correct execution of the athletic gesture is linked with a dynamic stabilization of the humeral head. In conclusion, the kinematic analysis could help in the early identification of the kinematic alteration to build a tailored rehabilitation plan based on the athlete's needs.

Dry Needling versus Diacutaneous Fibrolysis for the Treatment of the Mechanical Properties of the Teres Major Muscle: A Randomized Clinical Trial

(1) Background: The stiffness of the posterior shoulder muscles has been shown to be related to shoulder pain and range of motion (ROM) restriction in athletes. Specifically, the treatment of the teres major muscle showed promising results in previous studies. The aim of this study was to compare the effects of dry needling (DN) vs. diacutaneous fibrolysis (DF) to improve the stiffness and tone of the teres major muscle, pain intensity, shoulder ROM, and extensibility in the short-term and at one-week follow-up in handball athletes. (2) Methods: A randomized clinical trial with blinded examiners was carried out. Elite handball athletes with shoulder pain and glenohumeral internal rotation deficit (n = 30) were randomly allocated to the DN group or the DF group. Patients in both groups received a single treatment session directly applied to the teres major muscle. The primary outcome variables and instrument were mechanical properties of the teres major muscle (stiffness and tone) measured with myotonometry. The secondary outcome variables were intensity of shoulder pain evaluated with visual analogue scale and shoulder ROM and extensibility recorded with a digital inclinometer. (3) Results: No between-group differences were found after the intervention or at one-week follow-up in the mechanical properties of teres major muscle, pain intensity, shoulder ROM, or extensibility. (4) Conclusions: the DN and DF techniques showed similar results at both timepoints in elite handball athletes with shoulder pain and glenohumeral internal rotation deficits.

Throwing Shoulder Adaptations Are Not Related to Shoulder Injury or Pain: A Preliminary Report.

Overhead throwing in baseball and softball athletes induces shoulder adaptations theorized to increase risk of shoulder musculoskeletal injury (MSI) and/or pain due to range of motion (ROM) deficits. Shoulder ROM adaptations are associated with a higher risk for developing shoulder MSI and pain. Prospective cohort study. Level 3. A total of 60 National Collegiate Athletic Association Division I athletes cleared for full athletic participation and free from upper extremity MSI in the last 4 weeks (age, 19.0 ± 1.2 years; weight, 82.1 ± 13.7 kg; height, 178.6 ± 11.2 cm; softball, n = 23; baseball, n = 37). Passive glenohumeral internal rotation (IR), external rotation (ER), and horizontal adduction (HA) ROM were measured with the scapula stabilized and used to categorize participants with/without external rotation gain (ERG), external rotation insufficiency (ERI), glenohumeral internal rotation deficit (GIRD), pathological GIRD, and posterior shoulder tightness (PST) before the competitive season. Groups were then compared to assess the incidence of shoulder MSI prospectively and prevalence of shoulder pain at the initial evaluation. Baseball and softball athletes demonstrated significantly less IR ROM in the dominant shoulder (50.6° ± 9.4°) compared with the nondominant shoulder (59.1° ± 8.6°; P < 0.01) and significantly more ER ROM (dominant, 104.6° ± 12.1°; nondominant, 97.7° ± 12.0°; P < 0.01). Incidence of shoulder MSI was 15% but was not significantly related to any shoulder adaptations. No significant relationship was found between prevalence of pain and any shoulder adaptations in the 27% of athletes with pain. Increased ER and decreased IR ROM adaptations in intercollegiate overhead throwing athletes do not appear to be correlated to risk of shoulder MSI or pain. The findings of this level 3 prospective study provide clinicians working with overhead athletes information regarding shoulder MSI risk and pain. It is recommended that clinicians should not use ROM adaptations exclusively to determine increased risk of shoulder MSI.

MODİFİYE POSTERİOR OMUZ GERME EGZERSİZLERİNİN POSTERİOR OMUZ GERGİNLİĞİ VE GLENOHUMERAL İNTERNAL ROTASYON DEFİSİTİNDEKİ ETKİNLİĞİ: BİR SİSTEMATİK DERLEME

Purpose: Posterior shoulder tightness (PST) and Glenohumeral internal rotation deficit (GIRD) can impact shoulder biomechanics and damage shoulder function. Posterior shoulder stretching exercises (PSSEs) are often performed in traditional positions to improve posterior shoulder inflexibility. However, these traditional positions can cause inadequate control of the scapula and glenohumeral rotation. The modified PSSEs through scapular stabilization are preferred as current trends to effective management of the GIRD and PST. However, there is a lack of consensus regarding which type of modified PSSE is more effective on PST and GIRD improvement. Therefore, we aimed to describe the efficacy of modified PSSEs on PST and GIRD in symptomatic and asymptomatic populations to aid clinicians when making decisions for these populations. &#x0D; Methods:A literature search was conducted for a systematic review. Relevant studies were searched from appropriate electronic databases (CINAHL, Cochrane Review, Pubmed (MEDLINE), Web of Science as well as Google Scholar©), and selected the eligible studies for inclusion.&#x0D; Results: The present systematic literature search generated 127 relevant citations and 17 articles were included in the final review. As an outcome measure GIRD was assessed in all included studies, whereas PST was assessed in 10 studies.There was high evidence related to the positive effects of both modified cross-body and sleeper stretch to improve GIRD and PST.&#x0D; Conclusion: According to this systematic literature review, both modified cross-body and sleeper stretch are effective in the improvement of GIRD and PST. Future research should focus on other specific shoulder diseases and should also recruit specific participants to address the effectiveness of modified PSSEs on GIRD and PST.

EFFECTIVENESS OF MUSCLE ENERGY TECHNIQUES ON GLENOHUMERAL INTERNAL ROTATION DEFICIT IN OVERHEAD ATHLETES: A SYSTEMATIC REVIEW

Purpose: Posterior shoulder tightness (PST) and Glenohumeral Internal Rotation Deficit (GIRD) are frequent biomechanical changes in overhead athletes. Evidence has shown that PST and the presence of GIRD increase subacromial pain syndrome. Posterior shoulder stretching exercises are used to improve posterior shoulder tightness. Muscle Energy Techniques (MET) are a long-established and effective approach, and the number of studies investigating the effects of MET on GIRD has been increasing in recent years. Despite the use of static stretching techniques in training, GIRD continues to be common in athletes performing overhead activities. Therefore, revealing the effects of MET on GIRD might be effective in determining the type of stretching most appropriate for preventing GIRD in athletes.&#x0D; Methods: We performed a systematic literature review, assessing the relevance of studies for inclusion and selecting the studies from appropriate electronic databases (CINAHL, Cochrane Review, Pubmed (MEDLINE), Web of Science as well as Google Scholar©).&#x0D; Results: The present systematic literature search generated 178 relevant citations and 8 articles were included in the final review. As an outcome measure, GIRD was assessed in all eight, whereas PST was assessed in four.&#x0D; Conclusion: According to this systematic literature review, MET is effective in the improvement of GIRD and PST in overhead athletes. Future research should focus on symptomatic shoulders and investigate the long-term benefits of MET.

Increased Tone and Stiffness of the Teres Major Muscle in Elite Handball Athletes: A Cross-Sectional Study

Background: The aim of this study was to determine whether the elite handball (HB) athletes with glenohumeral internal rotation deficit (GIRD) present differences in the mechanical properties in the teres major muscle, and strength and extensibility of the posterior shoulder tissues of the throwing shoulder (TS) compared to the non-throwing (non-TS) and non-HB athletes. Methods: A cross-sectional study was carried out, with sixty male participants: 30 HB athletes with GIRD and 30 age-matched healthy non-HB athletes. Mechanical properties of the teres major muscle were measured with MyotonPRO; also, extensibility of the posterior shoulder tissues and maximum isometric internal rotation (IR) and external rotation (ER) strength were recorded. Results: The teres major muscle of the TS in the HB group achieved a higher tone (Δ 0.34; 95% CI: 0.15, 0.53) and stiffness (Δ 30.86; 95% CI: 23.04,38.68), and a lower relaxation time compared to the non-TS of the same group (Δ −0.69; 95% CI: −1.15, −0.24;) and to the TS of the control group for the tone (Δ 0.36; 95% CI: 0.02, 0.70) and for the stiffness (Δ 27.03; 95% CI: 15.24, 38.83). The extensibility of the TS of the HB group presented a statistically significant decrease compared to the control group (Δ−7.83; 95% CI: −12.42, 3.23). A between-groups ER/IR ratio imbalance was found for the TS (Δ−12.18; 95% CI: −25.59, −1.23) and the non-TS (Δ−13.01; 95% CI: −25.79, −0.25). Conclusions: HB athletes with GIRD present a higher tone and stiffness of the teres major muscle and lack of extensibility of the tissues of the posterior part of the shoulder compared to the non-TS and to healthy non-HB athletes.

Effect of core-shoulder stability exercises on shoulder performance among throwers with glenohumeral internal rotation deficit

The study aimed to find out the effect of core-shoulder stability exercises on shoulder performance among throwers with glenohumeral internal rotation deficit (GIRD). Out of Forty-two athletes who participated, 30 subjects were selected who fulfilled the selection criteria and were randomized into 2 groups with 15 subjects in each group. Throwing accuracy (functional throwing performance index), throwing distance (overall medicine throw test), and shoulder range of motion were assessed and recorded at baseline, 3rd week, and 6th week of intervention. The control group received shoulder stability exercises while the study group received core-shoulder stability exercises 4 days per week for 6 consecutive weeks. Repeated measure ANOVA was used to see the difference between groups (groups 1 and 2) and time (baseline,3rd week, and 6th week ) Averaged across times statistically significant improvement was found in overhead medicine ball throw in the study group (Group 2) as compared to the control group with p&lt;0.05. No significant difference was found in the functional throwing performance index and range of motion when groups were compared across times. However, for all the outcome measures when compared across groups, a significant difference was found between 6th and 3rd-week scores as compared to baseline scores. This indicates improvements were seen in both groups independently. We conclude that core stability and shoulder stability training both improve the range of motion with throwing accuracy and distance. Core stability training improves throwing distance compared to shoulder stability training in subjects with GIRD.

The Effect of 8-week Online Scapular-focused Training on Scapular Kinematics, Proprioception, and Selected Muscles Strength in Female Volleyball Players With Glenohumeral Internal Rotation Deficit

Purpose: One of the most significant risk factors for throwing athletes is an internal rotation deficit of the shoulder joint. This study aims to investigate 8-week online scapular-focused training on the scapular kinematics, proprioception, and strength of particular shoulder muscles in female volleyball players with glenohumeral internal rotation deficit. Methods: The present study was conducted using a two-group with pre and post-test design. Based on the inclusion and exclusion criteria, 30 female athletes with abnormalities in the shoulder joint’s internal rotation were split into two groups, experimental (n=15) and control (n=15). In the pre-test, goniometers were used to measure shoulder range of motion, isokinetic devices were used to measure proprioception and rotator cuff muscle strength, and inclinometers were used to measure scapular kinematics. The experimental group’s participants underwent 8-week online scapular-focused training, lasting 30 minutes over three sessions each week. These exercises encompassed strength (with TheraBand) and stretching activities. Ultimately, intra-group and inter-group differences were examined using SPSS software, version 20 using paired t-tests and analysis of covariance (ANCOVA) at a significance level of 0.95. Results: The results of paired t-test revealed that only the experimental group and the pre-test and post-test had a significant difference in all study variables (P&lt;0.05). Additionally, the results of the analysis of covariance (ANCOVA) demonstrated a significant difference between the two groups’ shoulder proprioception at 45° and 90° in the post-test (P=0.001 and P=0.01, respectively). The two groups also differed significantly in the scapular kinematics at all angles of 45°, 90°, and 135° as well as at the limit of the shoulder’s range of motion (P=0.01, P=0.04, P=0.001, and P=0.001, respectively). Additionally, significant differences were observed between the two groups in all variables of isokinetic strength of concentric internal rotation, isokinetic strength of concentric external rotation, isokinetic strength of eccentric internal rotation, and isokinetic strength of eccentric external rotation (P=0.001, P=0.02, and P=0.001, respectively). Conclusion: Based on the results, it can be concluded that 8-week online scapular-focused training improves scapular kinematics, proprioception, and shoulder internal and external rotator muscle strength in female volleyball players experiencing internal rotation deficiencies of the shoulder joint. It is advised that coaches, experts, and occupational therapists employ these workouts to enhance the aforementioned factors in female volleyball players experiencing shoulder internal rotation deficiencies.