Glenohumeral Internal Rotation Deficit Research Articles

The Biomechanics of Shoulder Movement with Implications for Shoulder Injury in Table Tennis: A Minireview.

A high proportion of shoulder injuries in table tennis players are common, which is both a diagnostic and therapeutic challenge. An understanding of the interaction between biomechanical function of the shoulder and mechanisms of shoulder injuries in table tennis players is necessary to prevent injury and to conduct clinical treatment of the shoulder as soon as possible. The purpose of this minireview was to select the available evidence on the biomechanical characteristics of shoulder movement and potential relationships with various shoulder injuries that are common in table tennis players. Five studies revealed interesting biomechanical characteristics of shoulder movement patterns in table tennis players: large internal rotation torque, an increased torsion-rotation movement, and a greater angular velocity of internal rotation were found. Two studies were noted that were related to specific shoulder injury: glenohumeral internal rotation deficit (GIRD) and impingement syndrome. Unfortunately, it is difficult to draw conclusions on the mechanisms of shoulder injury in table tennis players due to the little evidence available that has investigated shoulder injury mechanisms based on biomechanical characteristics. Future studies should focus on the potential relationship between the biomechanical characteristics of the shoulder and injury prevalence to provide valuable reference data for clinical treatment.

Effect of a novel stretching technique on shoulder range of motion in overhead athletes with glenohumeral internal rotation deficits: a randomized controlled trial

BackgroundThe cross-body and the modified sleeper stretch have been used to improve posterior shoulder soft tissue flexibility and to increase glenohumeral joint internal rotation (GHJ IR) in overhead athletes. However, due to the inability to stabilize patient’s scapula and control GHJ rotation with the cross-body stretch and the potential for subacromial impingement or symptoms’ aggravation with the modified sleeper stretch, a new stretching technique (Passive Glenohumeral Internal Rotation with Clam Shell Bridging) was developed as an alternative to these commonly used stretches that may allow for greater stability of the scapula without reproducing symptoms. Thus, the current study aimed to examine and compare a novel stretching technique to the traditional modified sleeper stretch to determine the effect on glenohumeral IR range of motion (ROM) and self-reported pain in overhead athletes with glenohumeral internal rotation deficits (GIRD).MethodsForty-two overhead athletes with GIRD [mean age 25.9 ± 2.6 years, 20 males and 22 females] participated in this study. Participants were randomly assigned into either novel stretching group or modified sleeper stretching group. IR ROM was measured with a digital inclinometer before, immediately, and at week 4 post intervention, while pain was measured with Numeric Pain Rating Scale before and at week 4 post intervention.ResultsThere was no significant group by time interaction effect for IR ROM (p = 0.27); however, there was a significant change over time (p < 0.001, η2 = 0.77). Both groups demonstrated a significant increase in IR from baseline to immediate and week 4, and from immediate to week 4 (p < 0.001). There was a significant group by time interaction for pain intensity (p < 0.001, η2 = 0.72). Results showed a significant reduction in pain intensity over time in the novel group (p = 0.001, d = 2.18), but not in the traditional group (p = 0.231, d = 0.46).ConclusionBoth stretches appear to be effective at improving IR ROM in overhead athletes with GIRD. However, the novel stretching might be more effective at reducing shoulder pain and thus may be more appropriate for symptomatic patients.Trial registrationProspectively registered in February 6, 2017 under Clinical Trial Registry # NCT03044236.

The Relationship between the Glenohumeral Joint Internal Rotation Deficit and the Trunk Compensation Movement in Baseball Pitchers.

Background and objectives: Glenohumeral joint internal rotation deficit (GIRD) is commonly observed in the dominant arm of baseball pitchers and is limited by horizontal adduction motions. We inferred that when pitchers’ generation of internal shoulder rotation and horizontal adduction activity is limited, they may generate compensation movements in other body parts. This study aims to investigate whether pitchers with GIRD generates trunk compensation during pitching where pitching targets were on the lower corner of their non-dominant side. Design: Case-control study. Setting: Elite senior high school baseball. Participants: Twenty-five senior high school baseball pitchers participated in this study. Twelve pitchers with GIRD were assigned to the experiment group, and the remaining 13 participants to the control group. Main outcome measures: Glenohumeral internal/external rotation of both arms and internal/external rotation of the bilateral hip joints were measured. The kinematic values of the trunk when pitching to a target were measured using high-speed infrared cameras. Results: Pitchers with GIRD exhibited significantly greater upper trunk rotation toward the non-dominant side when a baseball was released from their hand (27.39 ± 6.62 degrees), compared with non-GIRD pitchers (20.42 ± 5.97 degrees) (p < 0.05). The total rotation of the pivot leg of pitchers with GIRD (67.54 ± 7.84 degrees) was significantly smaller than that of pitchers without GIRD (74.00 ± 7.07 degrees) (p < 0.05). Conclusions: GIRD in the dominant arm affected upper trunk rotation during pitching and was associated with the hip range of motion. Future studies could conduct a longitudinal study regarding the relationship between GIRD and other joint injuries of the lower limbs.

Comparison of the Effects of Static-Stretching and Tubing Exercises on Acute Shoulder Range of Motion in Collegiate Baseball Players

BackgroundThe overhead throwing motion repetitively stresses the dominant arm in baseball players, frequently altering normal range of motion (ROM) in multiple directions. Baseball players regularly perform a combination of static stretches (SS) and dynamic tubing (DT) resistance exercises in pre-throwing warm-up routines intended to improve shoulder ROM and reduce injuries.PurposeThe purpose of this study was to compare acute changes in dominant shoulder ROM improvements between SS and DT warm-up exercise protocols. The DT exercises were hypothesized to elicit greater improvements in shoulder ROM.Study DesignTwo-way crossover study.MethodsTwenty-five healthy collegiate baseball players (mean age = 19.8 ±1.0 years) presenting with glenohumeral internal rotation deficit (GIRD) >20° and total rotational range of motion (TRROM) losses >5° completed the SS and DT interventions on different days. Dominant arm internal rotation (IR), external rotation (ER) and TRROM were measured before, immediately after, 30-minutes after, and 60-minutes after each treatment session. A two-way repeated measures analysis of variance (ANOVA) compared the effect of SS and DT over time on IR, ER and TRROM.ResultsIR improved on average 10.68 ± 0.82° (p < .001) post intervention, 11.18 ± 0.79° (p < .001) 30-min post intervention, and 9.03 ± 0.95° (p < .001) 60-min post intervention. ER improved on average 8.60 ± 0.67° (p < .001) post intervention, 8.25 ± 0.85° (p < .001) 30-min post intervention, and 6.65 ± 0.91° (p < .001) 60-min post intervention. TRROM improved on average 19.28 ± 1.09° (p < .001) post intervention, 19.43 ± 1.36° (p < .001) 30-min post intervention, and 15.68 ± 1.55° (p < .001) 60-min post intervention. There were no significant differences between the main effects of treatment and time for IR, ER, and TRROM. For IR, SS improved by an average of 1.73 ± 0.55° (p = .005) more than DT. For ER and TRROM, there were no differences between SS and DT.ConclusionBoth SS and DT exercises improve glenohumeral IR, ER and TRROM up to one-hour post intervention, with no significant differences noted between interventions for treatment or time. Baseball players can benefit equally from performing SS or DT exercises to acutely improve shoulder ROM.Level of EvidenceLevel 3

Chronic Adaptations of the Posterior Rotator Cuff in Professional Pitchers

Background: Because of the large forces and high frequency of throwing, the upper extremity experiences repetitive stresses that lead to acute and chronic adaptations. While the importance of pennation angle and muscle thickness as predictors of muscle force production has been shown in other populations and other joints, there has been little research done that examines these variables in the shoulders of baseball players. Purpose: (1) To examine the chronic effect pitching has on the rotator cuff muscle architecture (pennation angle and muscle thickness) in healthy professional baseball pitchers, and (2) to examine the correlation between muscle architecture and clinical measures of strength and range of motion (ROM). Study Design: Cross-sectional study; Level of evidence, 3. Methods: Twenty-eight healthy professional pitchers were recruited during the 2019 spring training. Internal rotation (IR) and external rotation (ER) strength were measured with a handheld dynamometer and IR and ER ROM were measured with an inclinometer. A diagnostic ultrasound machine was utilized to capture images of humeral retroversion, as well as the pennation angle and muscle thickness of the infraspinatus and teres minor muscles. ImageJ software was used to quantify the pennation angle and muscle thickness. Results: There were no significant differences between the dominant and nondominant arms for ER or IR strength. Also, no pennation angle and muscle thickness differences were found between the dominant and nondominant arms. A weak positive relationship between infraspinatus muscle thickness (superficial and total) and ER strength (P = .016, R = 0.287 and P = .009, R = 0.316) and a moderate negative relationship between soft tissue glenohumeral internal rotation deficit (GIRD) and the bilateral difference of the teres minor deep pennation angle (R = −0.477, P = .008) were observed. No other significant relationships were noted. Conclusion: Our results are contrary to current literature as we expected to see a stronger dominant arm, with a larger pennation angle and greater muscle thickness. Interestingly, we found that ER strength was positively related to only the thickness of the infraspinatus muscle, and that soft tissue GIRD was positively related to only the side-to-side adaptation of the pennation angle within the deep portion of the teres minor. This suggests that when posterior shoulder tightness occurs, specifically the architecture of the teres minor muscle is involved. However, the organization to which these players belonged has a very extensive training protocol throughout the year that emphasizes bilateral training during a large majority of the exercises. Therefore, the results may not be generalizable to all professional players.

The Effect of Straight-Line Long-Toss Versus Ultra-Long-Toss Throwing on Passive Glenohumeral Range of Motion Recovery After Pitching.

Repetitive throwing in baseball pitchers can lead to pathologic changes in shoulder anatomy, range of motion (notably glenohumeral internal rotation deficit), and subsequent injury; however, the ideal strengthening, recovery, and maintenance protocol of the throwing shoulder in baseball remains unclear. Two strategies for throwing shoulder recovery from pitching are straight-line long-toss (SLT) throwing and ultra-long-toss (ULT) throwing, although neither is preferentially supported by empirical data. ULT will be more effective in returning baseline internal rotation as compared with SLT in collegiate pitchers after a pitching session. Cohort study. Level 3. A total of 24 National Collegiate Athletic Association Division I baseball pitchers with mean age 20.0 ± 1.1 years were randomized to either the ULT group (n = 13; 9 right-hand dominant, 4 left-hand dominant) or SLT group (n = 11; 10 right-hand dominant, 1 left-hand dominant). Measurements (dominant and nondominant, 90° abducted external rotation [ER], internal rotation [IR], and total range of motion [TROM]) were taken at 5 time points across 3 days: before and immediately after a standardized bullpen session on day 1; before and immediately after a randomized standardized ULT or SLT session on day 2; and before practice on Day 3. ULT demonstrated significantly greater final ER compared with baseline (+10°; P = 0.05), but did not demonstrate significant IR changes. Similarly, SLT demonstrated significantly greater post-SLT ER (+12°; P = 0.02) and TROM (+12°;P = 0.01) compared with baseline, but no significant IR changes. Final ER measurements were similar between ULT (135° ± 14°) and SLT (138° ± 10°) (P = 0.59). There was also no statistically significant difference in final IR between ULT (51° ± 14°) and SLT (56° ± 8°) (P = 0.27). The routine use of postperformance, ULT throwing to recover from range of motion alterations, specifically IR loss, after a pitching session is not superior to standard, SLT throwing. Based on these findings, the choice of postpitching recovery throwing could be player specific based on experience and comfort. The most effective throwing regimens for enhancing performance and reducing residual impairment are unclear, and ideal recovery and maintenance protocols are frequently debated with little supporting data. Two strategies for throwing shoulder recovery from pitching are SLT and ULT throwing. These are employed to help maintain range of motion and limit IR loss in pitchers. The routine use of ULT throwing for recovery and to limit range of motion alterations after a pitching session is not superior to SLT throwing.

Comparison of the Acute Effects of Kinesio Taping and Sleeper Stretching on the Shoulder Rotation Range of Motion, Manual Muscle Strength, and Sub-Acromial Space in Pitchers with Glenohumeral Internal Rotation Deficit.

Background and Objectives: Sleeper stretching (SS) can improve the shoulder’s range of motion (ROM) for pitchers with glenohumeral internal rotation deficit (GIRD). However, no evidence has proven the effect of Kinesio taping (KT) on shoulder strength and ROM. Therefore, this study compared the effects of SS and KT on shoulder rotation ROM, muscle strength, and sub-acromial distance in pitchers with GIRD. Materials and Methods: Thirty-one pitchers with GIRD were allocated into control, KT, and SS groups. Shoulder rotation ROM, muscle strength, and sub-acromial space were measured before and after treatment with SS or KT. Results: The results revealed that KT and SS significantly enhanced shoulder rotation ROM in pitchers with GIRD. External rotator strength significantly increased following KT but significantly decreased after SS. KT and SS exerted no effects on the sub-acromial space. Conclusions: KT and SS improve shoulder rotation ROM in pitchers with GIRD. In addition, KT improves shoulder external rotator strength, and SS reduces it.

The potential impact from glenohumeral internal rotation deficit to the knee kinematics in baseball pitchers: A case-control study.

A recent study suggested that baseball pitchers with glenohumeral internal rotation deficit (GIRD) may tend to use trunk rotation as compensation to adjust ball placement, which may lead to subsequent counter movement at the knee of the leading leg.This study aims to investigate the kinematic characteristics of the counter movements between the femur and the tibia (knee torsion), from the landing of the leading leg until the follow-through phase, during throwing between pitchers with and without GIRD at the dominant arm.This is a case-control study. Twenty-one senior high school baseball pitchers were recruited in this study. The glenohumeral internal and external rotation, hip internal and external rotation of all participants were measured. Eight pitchers without GIRD and 13 pitchers with GIRD were enrolled into the control group and experiment group, respectively. The maximal angular movement between the femur and the tibia (knee torsion) of the leading leg was measured, using The Zebris 3D (Zebris Medizintechnik GmbH, Isny, Germany) motion analysis system, in the interval from the landing until the follow-through phase during pitching a fastball to the bottom-outside corner with their dominant arm.The results showed that the maximal knee torsion of the leading leg in the experimental group (13.67 ± 0.9 degrees) was significantly greater than the control group (4.25 ± 1.369 degrees) (P < .05).Pitchers with GIRD had greater counter movement in the knee joint than pitchers without GIRD.

Soft Tissue Mobilization and Stretching for Shoulder in CrossFitters: A Randomized Pilot Study.

Background. The shoulder in CrossFit should have a balance between mobility and stability. Glenohumeral internal rotation deficit and posterior shoulder stiffness are risk factors for overhead shoulder injury. Objective. To determine the effectiveness of instrument-assisted soft tissue mobilization and horizontal adduction stretch in CrossFit practitioners’ shoulders. Methods: Twenty-one regular CrossFitters were allocated to experimental (stretching with isometric contraction and instrument-assisted soft tissue mobilization) or control groups (instrument-assisted soft tissue mobilization). Each session lasted 5 min, 2 days a week, over a period of 4 weeks. Shoulder internal rotation and horizontal adduction (digital inclinometer), as well as posterior shoulder stretch perception (Park scale), were evaluated. Shapiro–Wilk test was used to analyze the distribution of the sample. Parametric Student’s t-test was used to obtain the intragroup differences. The inter- and intra-rater differences were calculated using a repeated measures analysis of variance (ANOVA). Results. Average age was 30.81 years (SD: 5.35), with an average height of 178 (SD: 7.93) cm and average weight of 82.69 (SD: 10.82) kg. Changes were found in the experimental group following intervention (p < 0.05), and when comparing baseline and follow-up assessments (p < 0.05) in all variables. Significant differences were found in the control group following intervention (p < 0.05), in right horizontal adduction and left internal rotation. When comparing the perception of internal rotation and horizontal adduction in both groups, significant differences were found. Conclusions. Instrument-assisted soft tissue mobilization can improve shoulder horizontal adduction and internal rotation. An instrument-assisted soft tissue mobilization technique yields the same results alone as those achieved in combination with post-isometric stretch with shoulder adduction.

Relationship between glenohumeral internal rotation deficit and shoulder conditions in professional baseball pitchers

Previous studies have reported that glenohumeral internal rotation deficit (GIRD) may increase the risk of throwing-shoulder injuries. The purpose of this study was to analyze the conditions of the throwing shoulder in professional baseball pitchers with GIRD by comparing with those in pitchers without GIRD. In total, 26 male professional baseball pitchers participated in this study. We evaluated passive range of motion (ROM) and isometric muscle strength at internal rotation (IR) and external rotation (ER) at 90° of abduction, as well as the muscle thickness of the supraspinatus (SSP) and infraspinatus (ISP) by ultrasound. The pitchers were divided into 2 groups: those who exhibited a loss of IR of ≥20° in the throwing shoulder (GIRD group) and those who did not (non-GIRD group). In the GIRD group, the total ROM deficit (throwing side - non-throwing side) (P < .001), the muscle thickness ratio (throwing to non-throwing) of the SSP and ISP (P = .017 and P = .014, respectively), and the muscle strength ratio (throwing to non-throwing) of ER (P = .028) were significantly lower than those in the non-GIRD group. In contrast, the muscle strength ratio (throwing to non-throwing) of IR was significantly higher in the GIRD group than in the non-GIRD group (P = .0064). We have shown that GIRD has significant correlations with several conditions, such as atrophy of the SSP and ISP, weakness of ER strength, enhancement of IR strength, limitation of total ROM, and throwing side, all of which could be important factors for throwing-shoulder injuries.

Effect of Glenohumeral Internal Rotation Deficit on Shoulder in Baseball Pitchers during Fastball Pitching

Previous studies have reported that pitchers with glenohumeral internal rotation deficit (GIRD) may increase the risk of shoulder injury. However, limited information is available regarding the specific effects of GIRD in baseball pitching. The purpose of this study was to investigate whether baseball pitchers with GIRD change their pitching mechanism. Fifteen baseball pitchers with GIRD and 15 pitchers without GIRD were recruited from university or senior high-school teams. A three-dimensional motion analysis system (Eagle System, Motion Analysis Corporation, Santa Rosa, CA, USA) was used to capture the pitching motion while performing fastball pitches. The kinematics and kinetics of the throwing shoulder and trunk were analyzed based on motion captured data. The Mann–Whitney U test was used to test the differences of the analyzed parameters between two groups. At the instant of ball release, the GIRD group showed lower shoulder external rotation and trunk rotation, and larger shoulder horizontal adduction. In addition, the GIRD group exhibited a significantly larger shoulder inferior force in the cocking and acceleration phase, and a significantly larger internal rotation torque in the acceleration phase. The present results suggested that pitchers with GIRD need stretch training to enlarge joint range of motion, and to improve trunk strength and flexibility to alleviate potential problems associated with pitching in GIRD pitchers.

Effect of Fascial Manipulation on Glenohumeral Internal Rotation Deficit in Overhead Athletes - A Randomized Controlled Trial

Background. Glenohumeral Internal Rotation Deficit (GIRD) is common among overhead athletes and is considered as one of the risk factors for upper extremity injuries.GIRD is usually managed by stretching and soft tissue release of the posterior shoulder capsule. Fascial manipulation is a manual therapy technique used in the management of musculoskeletal disorders. This study compared the efficacy of fascial manipulation (FM)with posterior capsular ball release and stretching on GIRD.Purpose. The purpose of this study is to determine the effect of Fascial Manipulation (FM) on the Internal Rotation Range of Motion (IRROM) in athletes with GIRD. Since studies have shown a possible association between GIRD and shoulder injuries, improving the IRROM in athletes with GIRD may help in reducing the risk of shoulder injuries. Thus,FM may be used as an effective strategy in increasing IRROM in overhead athletes with GIRD, thus preventing upper extremity injuries.Study Design. Randomized controlled trial.Methods. Asymptomatic overhead athletes with GIRD more than 20° when compared with the non-dominant shoulder were randomly assigned to two groups. The experimental group has received three sessions of FM treatment in two weeks. FM applied to densified Centre of Coordination (CC) points located on the myofascial sequences for 5 to 8 minutes at each CC point. The control group has received three sessions of posterior shoulder capsule release using a tennis ball under supervision. Along with the ball release, the therapist taught home-based, unsupervised sleeper, and cross-body adduction stretches, for the control group. A universal goniometer was used to measure the IRROM before and after all three treatment sessions in both groups. Results. There were no statistically significant differences between the control and experimental groups (p< 0.05). However, immediate improvement in the IRROM following FM was more substantial in the experimental group following each session.Conclusions. This study indicates that FM may be used as an adjunct to stretching in asymptomatic participants with GIRD to increase the IRROM. There is a scope for future studies to be done to investigate the effect of FM on symptomatic overhead athletes with GIRD

Correlation of glenohumeral internal rotation deficit with shear wave ultrasound elastography findings for the posterior inferior shoulder capsule in college baseball players

The glenohumeral internal rotation deficit (GIRD), primarily caused by the tightness of the posterior capsule, is a major risk factor for shoulder injuries in overhead throwing athletes. Quantitative evaluation of posterior capsular thickness and tightness can help determine the relationship between the posterior inferior capsule and GIRD. One previous study has assessed posterior capsule tightness using shear wave elastography (SWE), in college baseball players; however, it did not address the cutoff value of capsular elasticity that could be considered as abnormal capsular tightness. We aimed to re-evaluate effectiveness of SWE in quantifying posterior shoulder capsule tightness in college baseball players and determine the cutoff value of abnormal capsular elasticity that can predict impending throwing-related shoulder injuries associated with GIRD. Twenty-four college baseball players were enrolled in this study. External and internal rotation of the shoulder joint was assessed. The participants were classified into the GIRD group if their throwing shoulder showed >20° of internal rotation loss compared with their nonthrowing shoulder. In a longitudinal ultrasonographic scan of the posterior inferior capsule, shear wave (SW) velocity and thickness were measured at the point nearest to the labrum on both shoulders. Of the 24 subjects, 6 had a GIRD. The mean value of the SW velocity in the throwing shoulder was greater in the GIRD group than in the non-GIRD group (P = .006). The SW velocity difference between the throwing and nonthrowing shoulder was also greater in the GIRD group than in the non-GIRD group (P < .001). There was no significant difference in the thickness of the posterior inferior capsule between both groups. In correlation analysis, the difference in the SW velocity was more strongly correlated with the GIRD than with the SW velocity in the throwing shoulder. When we assume that a 20° GIRD is indicative of a shoulder at risk, the cutoff SW velocity in the throwing shoulder is 4.81 m/s and the SW velocity difference is 0.77 m/s. The SW velocity is closely associated with posterior shoulder capsular tightness and may be of quantitative value in baseball players.

Glenohumeral internal rotation deficit in non-pitcher overhead athletic athletes: case series analysis of ten athletes

BackgroundThe glenohumeral internal rotation deficit (GIRD) is diagnosed when there is a loss of 20° of internal rotation compared to the contralateral shoulder. This condition has already been well described in a group of throwing athletes, i.e. baseball pitchers. However, athletic athletes such as javelin throwers, discus throwers, hammer throwers, shot putters may also be susceptible to this condition. Reports are lacking to recognize these symptoms as GIRD for these group of athletes. We aim to evaluate these subgroups of athletes for the possibility of GIRD. Materials and methodsWe examined ten athletes (javelin, hammer throwers, and shot putters) for signs of GIRD. Signs of loss of internal rotation were assessed by measuring shoulder range of motion (internal rotation and external rotation) in supine position and posterior shoulder tightness test. Complaints of shoulder pain, evidence of scapular malposition, inferior medial border prominence, coracoid pain and malposition, and dyskinesis of scapular movement (SICK) scapula, posterior shoulder flexibility test were examined. ResultsThe athletes had a mean training period of 3.8 years. One athlete had complaints of mild pain on their dominant shoulder. Two athletes had GIRD (20° and 25°) with no posterior shoulder tightness. Three athletes had posterior shoulder tightness, but normal total shoulder ROM (195°, 180°, and 185°). Three athletes had increased external rotation (105°, 100°, 125°). No subjects had scapular dyskinesia nor SICK scapula syndrome. All athletes had normal total shoulder ROM. ConclusionGlenohumeral internal rotation deficit could be present in non-pitcher overhead athletics athletes.

WITHDRAWN: Posterior shoulder tightness, joint position sense, and shoulder strength in subjects with and without glenohumeral internal rotation deficit

The Publisher regrets that this article is an accidental duplication of articles which have already been published in Physical Therapy in Sport (2018) e1-e7 http://dx.doi.org/10.1016/j.ptsp.2020.04.007 . The duplicate articles have therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal .

Injury and training history are associated with glenohumeral internal rotation deficit in youth tennis athletes

A glenohumeral internal rotation deficit (GIRD) of the shoulder, is associated with an increased risk of shoulder injuries in tennis athletes. The aim of the present study was to reveal the impact of 1) age, sex, specific training data (i.e. training volume, years of tennis practice, years of competitive play) and 2) upper extremity injuries on GIRD in youth competitive tennis athletes.A cross-sectional retrospective study design was adopted. Youth tennis players (n = 27, 12.6 ± 1.80 yrs., 18 male) belonging to an elite tennis squad were included. After documenting the independent variables (anthropometric data, tennis specific data and history of injury), the players were tested for internal (IR) and external (ER) shoulder rotation range of motion (RoM, [°]). From these raw values, the GIRD parameters ER/IR ratio and side differences and TRoM side differences were calculated. Pearson’s correlation analyses were performed to find potential associations of the independent variables with the GIRD outcomes.A significant positive linear correlation between the years of tennis training and IR side asymmetry occurred (p < .05). A significant negative linear relation between the years of tennis training and the ratio of ER to IR range of motion (RoM) in the dominant side (p < .05) was found. The analysis of covariance showed a significant influence of the history of injuries on IR RoM (p < .05).Injury and training history but not age or training volume may impact on glenohumeral internal rotation deficit in youth tennis athletes. We showed that GIRD in the dominant side in youth tennis players is progressive with increasing years of tennis practice and independent of years of practice associated with the history of injuries. Early detection of decreased glenohumeral RoM (specifically IR), as well as injury prevention training programs, may be useful to reduce GIRD and its negative consequences.

The relationship between shoulder range of motion and elbow stress in college pitchers

College pitchers with increased external rotation gain (ERG) produce increased medial elbow torque (elbow stress)whereas those with reduced total rotational range of motion (ROM) have reduced medial elbow torqueduring pitching. Pitchers were recruited from 3 college baseball teams. Players with prior injury or on pitching restrictions because of pain were excluded. Players were evaluated within 2 weeks before their first game of the season. Pitchers completed an intake survey, and shoulder and arm measurements were taken. Pitchers were fitted with a baseball sleeve that included a sensor at the medial elbow. The sensor calculated elbow torque, arm speed, arm slot, and shoulder rotation for each pitch, while a radar gun measured peak ball velocity. After adequate warm-up, pitchers threw 5 fastballs in a standardized manner off the mound at game-speed effort. The primary outcome evaluated the relationship between shoulder ROM and medial elbow torque. Additional outcomes evaluated pitcher characteristics and demographic characteristics in the context of shoulder ROM. Twenty-eight pitchers were included in the preseason analysis. The average age and playing experience were 20.1 years (standard deviation [SD], 1.3 years) and 15.3 years (SD, 1.8 years), respectively, with 2.5 years (SD, 1.2 years) playing at collegiate level. The dominant shoulder showed decreased internal rotation and increased external rotation (ER) relative to the nondominant side (P < .001). The average glenohumeral internal rotation deficitand ERG were 11.3° (SD, 9.87°) and 5.71° (SD, 8.8°), respectively. ERG ≥ 5° was a significant predictor of elbow stress during pitching (47.4 Nm [SD, 0.7 Nm] vs. 45.1 Nm [SD, 0.6 Nm], P = .014). Univariate associations showed that each additional degree of ER resulted in increased elbow torque (β estimate, 0.35± 0.06 Nm; P = .003). Conversely, decreased medial elbow torque was found in pitchers with reduced shoulder ROM (glenohumeral internal rotation deficit ≥ 20°: 43.5 Nm [SD, 1.1 Nm] vs. 46.6 Nm [SD, 0.5 Nm], P = .011; loss of total rotational ROM ≥ 5°: 43.6 Nm [SD, 1.1 Nm] vs. 46.6 Nm [SD, 0.5 Nm], P = .013)and in those with greater arm length (P < .05). College pitchers with increased ER produce greater medial elbow torque during the pitching movement. Each degree of increased ER was found to correlate with increased elbow torque and ball velocity. On the contrary, arm length and reduced shoulder ROM were associated with reduced medial elbow torque. This study suggests that increased ER in pitchers is associated with greater elbow stress during pitching.

THE EFFECTS OF ISOLYTIC AND STATIC POSTERIOR SHOULDER STRETCHING IN INDIVIDUALS WITH SUBACROMIAL IMPINGEMENT SYNDROME

Static posterior shoulder stretching exercise (PSSE) in modified cross-body position (MCBP) improves posterior shoulder tightness (PST) and glenohumeral internal rotation deficit (GIRD). Isolytic stretching (isotonic eccentric contraction) is a form of muscle energy technique. The effects of isolytic PSSE were not investigated in shoulder pathologies. PURPOSE: To investigate the effects of isolytic and static PSSE in MCBP on shoulder internal rotation (IR) and external rotation (ER) range of motion (ROM) and strength, PST, subacromial space (SAS), supraspinatus tendon thickness (SsTT), supraspinatus tendon occupation ratio (STOR), functionality and disability level in individuals having subacromial impingement syndrome (SIS) with GIRD. METHODS: Sixty-three participants having SIS with GIRD were randomly divided into three groups. Isolytic Stretching Group (ISG) and Static Stretching Group received standard physiotherapy and isolytic or static PSSE in MCBP. The control group (CG) received physiotherapy without PSSE. Shoulder ROM and PST were assessed with bubble inclinometer, strength with hand-held dynamometer, SAS (at 0° and 60° scapular plane shoulder elevation), SsTT, and STOR with ultrasonography, functionality and disability level with Modified Constant-Murley Scale and Quick Disability of the Arm-Shoulder-Hand Questionnaire. GIRD was determined by the difference in bilateral shoulder IR ROM. Data were analyzed with two-way ANOVA with repeated measures. RESULTS: All groups improved in terms of shoulder mobility, strength, SAS, STOR, functionality, and disability level after 4-weeks of treatment (p<0.05). IR ROM and SAS increased, PST, GIRD, and STOR decreased more in stretching groups compared to CG (p<0.001). Improvements in stretching groups were similar (p>0.05). ER ROM, strength, functionality, and disability levels improved more in ISG compared to CG (p<0.05). CONCLUSIONS: Standard physiotherapy including PSSE in MCBP is superior to treatment program without PSSE to improve shoulder mobility, SAS and STOR. Both isolytic and static stretchings are equally effective. Standard physiotherapy plus isolytic PSSE provided a greater improvement in ER ROM, strength, functionality and disability levels compared to treatment program without PSSE. Research was not founded.

Editorial Commentary for In Throwers with Posterior Instability, Rotator Cuff Tears are Common but Do Not Affect Surgical Outcomes

Superior labral pathology is an exceedingly common entity among throwers, and in recent years, a number of reports have elucidated the prevalence of posterior glenohumeral instability among overhead athletes (baseball, softball, volleyball.) However, within this unique patient population, these conditions should not be viewed as separate clinical entities, but, rather as findings that exist on a single pathomechanic spectrum. In 2020, we now know that the complexity of the symptomatic thrower’s shoulder is a consequence of the complex anatomic relationships between the biceps tendon, capsulolabral tissues, posterosuperior rotator cuff, and the glenoid. In 2003, Burkhart et al. noted that diminished glenohumeral range of motion (i.e. glenohumeral internal rotation deficit “GIRD”) was common among throwers with painful shoulders. These authors further described a posterior-inferior capsular contracture as the “essential lesion” in the development of diminished range of motion in conjunction with impingement of the supraspinatus tendon between the greater tuberosity and the posterior-superior labrum (“pathologic internal impingement”) [1,2]. It is this internal impingement that so often manifests as partial thickness, articular sided supraspinatus tears in the throwing athlete. But these findings are now perhaps better understood as sequelae of a number of anatomic factors, including humeral retrotorsion, contractures of the coracohumeral ligament, pectoralis, and anterior deltoid, as well as dynamic muscle stiffness that can occur in response to the repetitive strains involved in overhead throwing.

Efficacy of throwing exercise with TheraBand in male volleyball players with shoulder internal rotation deficit: a randomized controlled trial

BackgroundThe Glenohumeral internal-rotation deficit (GIRD) is related to the altered eccentric external-rotator (ER), the concentric internal-rotator (IR), muscle strength, and the ER: IR ratio. GIRD has been documented as a risk factor for shoulder injuries. However, few studies have investigated the effect of an exercise training on these parameters in athletes with GIRD. Therefore, the purpose of this study was to evaluate the effects of an 8-week throwing exercise with a TheraBand for retraining the rotator cuff on Electromyography (EMG) activity of selected muscles, rotator cuff muscle strength, the glenohumeral (GH) joint IR range of motion (ROM) and GH joint position sense in asymptomatic male volleyball players with GIRD.MethodsSixty male volleyball players with GIRD were randomized into either a training group or a control group. The experimental group underwent an 8-week throwing exercise with a TheraBand including 5 sessions of stretching and 3 sessions of strengthening exercises per week. The control group received an active self-exercise program. EMG (onset time and muscle activation), shoulder range of motion (ROMs), strength and GH joint position sense were all assessed pre and post trainings.ResultsThere were statistically significant within-group differences in the EMG activity of the anterior deltoid (p = 0.005), middle deltoid (p = 0.007), posterior deltoid (p = 0.004), infraspinatus (p = 0.001) and supraspinatus (p = 0.001) muscles, IR ROM (p = 0.001), rotator cuff muscle strength ratio (p = 0.001), and GH joint position sense (p = 0.033) in the experimental group. A 2 × 2 analysis of variance with a mixed model design and independent and paired t-tests were used for statistical analysis.ConclusionsThrowing exercise with a TheraBand improved shoulder muscle activation, IR ROM, rotator cuff muscle strength ratio and GH joint position sense in participants with GIRD. These findings may improve the treatment of GIRD in a clinical setting. Although the results are significant, further studies should follow up the long-term effects of the Throwing exercise with a TheraBand on GIRD.Trial registrationCurrent Controlled Trials using the UMIN-RCT website with ID number of, UMIN000038416 “Retrospectively registered” at 2019/10/29.