Glenohumeral Internal Rotation Deficit: Prime Suspect or Innocent Bystander?

PURPOSE OF REVIEW: Glenohumeral internal rotation deficit (GIRD) is a term used in the literature to describe the physiological adaptation that occurs in the dominant arm of the overhead-throwing athlete. The meaning of this term and the clinical significance and the rationale for its treatment have all been described with some ambiguity within the literature. GIRD as a measurement is multivariate. There is an adaptive bony component in humeral retroversion (HR) and muscular contributions in the form of thixotropy which can confound the capsular component of GIRD. Emerging diagnostic tools such as ultrasound can help differentiate between the bony and soft tissue contributions as well as provide a dynamic assessment in the throwing shoulder. The purpose of this review is to describe and differentiate between anatomical GIRD (aGIRD) and pathological GIRD (pGIRD), discuss the clinical significance of pGIRD and values reported within the literature, and describe its measurement and clinical treatment. RECENT FINDINGS: Recent literature has demonstrated that GIRD alone is not associated with injury risk of the upper extremity in the overhead athlete. Although past literature has demonstrated pGIRD as increasing injury risk, other variables such as external rotation (ER) deficit, horizontal adduction deficit, and shoulder flexion deficit have been associated with injury of the upper extremity while GIRD did not. Further, an appreciation for the difference between adaptive GIRD and pathologic GIRD has recently been emphasized to ensure optimal treatment addresses the pathologic portion of GIRD. The recent focus on early treatment approaches to pGIRD may play a role in its diminished risk association. This review offers the term humeral retroversion (HR) Corrected GIRD as a more clinically sensitive value that may provide the clinician a more precise rationale for the treatment of pGIRD. Currently, diagnostic ultrasound is a reliable and valid method for measuring HR in the overhead-throwing athlete. Future research that validates clinical methods for assessing HR could provide utility for clinical decision-making in the absence of diagnostic ultrasound.

Shoulder and Elbow Range of Motion Can Be Maintained in Major League Baseball Pitchers Over the Course of the Season, Regardless of Pitching Workload.

BACKGROUND: Studies examining the evolution of shoulder and elbow range of motion (ROM) in baseball pitchers over a single season have yielded inconsistent results. PURPOSE: To evaluate shoulder and elbow ROM in Major League Baseball (MLB) pitchers over a single season and to assess for correlations between these changes and measures of a pitcher's workload. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Bilateral shoulder ROM (internal rotation [IR], external rotation [ER], and total range of motion [TROM]) was assessed in 92 MLB pitchers pre- and postseason. Shoulder forward flexion (FF) was measured in 64 pitchers, horizontal adduction (HA) was measured in 87 pitchers, and elbow ROM was measured in 86 pitchers. Data collected included demographics (age, height, weight, and body mass index) and measures of workload for pitchers (pitches thrown, innings pitched, and mean fastball velocity). Pitchers were not specifically excluded if they had an injury during the season but had recovered and were actively pitching at the time of postseason measurements. The change in motion from pre- to postseason was measured and the associations with player demographics and workload were calculated by use of the Pearson correlation coefficient. RESULTS: On average, pitchers demonstrated an increase in dominant shoulder ER from 118.8° to 125.4° (P < .001) and TROM from 173.1° to 181.7° (P < .001). HA was increased by an average of 15.7° (P < .001). The average shoulder IR (P = .189), FF (P = .432), and elbow ROM (flexion, P = .549; extension, P = .185) remained similar over the span of the season. Average glenohumeral IR deficit did not increase. Pitcher demographics and measures of throwing workload (total pitches thrown, innings pitched, mean fastball velocity) were not significantly correlated with changes in shoulder or elbow ROM. CONCLUSION: Significant increases in dominant shoulder ER, TROM, and HA were identified in MLB pitchers over the course of a single baseball season. These ROM changes were not correlated with measures of pitching workload.

Decreased Hip Internal Rotation Increases the Risk of Back and Abdominal Muscle Injuries in Professional Baseball Players: Analysis of 258 Player-seasons.

INTRODUCTION: The relationship of hip range of motion (ROM) to shoulder, elbow, abdominal, and back injuries remains undefined. METHODS: We assessed hip ROM on players reporting to Major League Spring Training for an organization over six seasons (2010 to 2015). Hip ROM was correlated with player abdominal, back, shoulder, and elbow injury status for those seasons using multivariate binomial logistic regression analysis. RESULTS: A total of 258 player-seasons (129 pitchers and 129 position players) resulted in 20 back and 35 abdominal injuries across all players and 28 elbow and 25 shoulder injuries in pitchers. Hip ROM did not correlate with shoulder or elbow injuries. Hip internal rotation deficit of 5° correlated with core injury (odds ratio [OR], 1.40; P = 0.024 for pitchers; OR, 1.35; P = 0.026 for position players) and back injury (OR, 1.160; P = 0.022 for pitchers). DISCUSSION: Hip internal rotation deficits were predictive of back and abdominal injuries but not shoulder or elbow injury.

The Impact of Workload on the Evolution of Hip Internal and External Rotation in Professional Baseball Players Over the Course of the Season.

BACKGROUND: Although restricted hip range of motion (ROM) is associated with an increased risk for injuries in baseball players, the evolution of hip ROM over the season remains undefined. HYPOTHESIS: Hip ROM profiles would be symmetric between hips and positions (pitchers vs position players) but would decrease from preseason to postseason. Additionally, it was hypothesized that this decrease in motion would correlate with workload. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Bilateral hip ROM was assessed in 96 professional baseball players (54 pitchers, 42 position players) preseason and postseason. ROM comparisons were made between lead and trailing hips, pitchers and position players, and preseason and postseason measures. The change from preseason to postseason was correlated with player demographics and measures of workload for pitchers and position players. RESULTS: Preseason hip ROM was symmetric between hips; however, pitchers demonstrated increased preseason lead hip internal rotation (IR) (P = .018) and bilateral hip total ROM (TROM) (P < .020) compared with position players. From preseason to postseason, position players lost 7° of external rotation (ER) (P ≤ .005 ). In pitchers, the loss of IR correlated with increased pitches (P = .016) and innings (P = .037), while the loss of ER (P = .005 ) and TROM (P = .014) correlated with increasing mean fastball velocity. Workload for position players did not correlate with motion loss. CONCLUSION: Symmetric hip ROM profiles should be anticipated in baseball players; however, pitchers may have increased preseason IR and TROM and postseason ER and TROM relative to position players. Although loss of motion correlated with workload in pitchers, this was not the case for position players. Hip motion should be monitored over the course of the season. This is particularly true for pitchers who lose IR as workload increases, which may place them at a greater risk for injuries.

Return to Throwing after Shoulder or Elbow Injury.

PURPOSE OF REVIEW: Throwing places high demands on the human body, and specific characteristics are developed over time unique to these athletes. When returning to throw after injury, it is important to follow a criterion-based progression that allows the body to be prepared appropriately for the stresses that throwing will require. There is currently a void in the literature for criteria-based progression that helps these athletes return to the highest level of play. RECENT FINDINGS: As injury rates continue to rise in baseball, there is increased evidence showing contributions of the core and lower extremity to the baseball pitch. There is also additional data showing pitcher specific characteristics such as range of motion and scapular position in this unique population. The rehab professional should take into account every phase of the pitch starting from balance through ball release when designing a comprehensive return-to-throwing program. Returning an athlete back to a throwing sport can be an overwhelming task. The rehabilitation specialist must have a sound understanding of the throwing motion as well as any biomechanical implications on the body, contributions throughout the kinetic chain, range of motion, and strength characteristics specific to the thrower as well as proper tissue loading principles. It is important that these athletes are not progressed too quickly through their programs and that a criteria-based progression is followed. They should have normalized range of motion, strength, and scapular mechanics, followed by a sound plyometric progression. Once this is achieved, they are advanced to an interval throwing program with increasing distance, effort, and volume which should be tracked for workload, making sure they do not throw more than their body is prepared for.

Decreased Shoulder External Rotation and Flexion Are Greater Predictors of Injury Than Internal Rotation Deficits: Analysis of 132 Pitcher-Seasons in Professional Baseball.

PURPOSE: The primary aims of this work were to (1) describe normal range of motion (ROM) profiles for elite pitchers, (2) describe the characteristics of shoulder and elbow injuries in professional pitchers over a 6-year period in one Major League Baseball organization, and (3) identify ROM measures that were independently associated with a future shoulder or elbow injury. METHODS: Over 6 seasons (2010-2015), a preseason assessment was performed on all pitchers invited to Major League Baseball Spring Training for a single organization. ROM measures included shoulder flexion, horizontal adduction, external rotation (ER), internal rotation, as well as elbow flexion and extension, were measured for both the dominant and nondominant arm, and total range of motion and deficits were calculated. All noncontact shoulder and elbow injuries were identified. Using multivariate binomial logistic regression analysis to control for age, height, weight, and all other ROM measures, the factors associated with an increased risk of subsequent shoulder or elbow injury were identified. RESULTS: A total of 53 shoulder (n = 25) and elbow (n = 28) injuries occurred during 132 pitcher seasons (n = 81 pitchers). The most significant categorical risk factor associated with increased elbow injury rates was the presence of a shoulder flexion deficit >5° (odds ratio [OR] 2.83; P = .042). For continuous variables, the risk of elbow injury increased by 7% for each degree of increased shoulder ER deficit (OR 1.07; P = .030) and 9% for each degree of decreased shoulder flexion (OR 1.09; P = .017). None of the measures significantly correlated with shoulder injuries. CONCLUSIONS: Preseason shoulder ER and flexion deficits are independent risk factors for the development of elbow injuries during the upcoming season. Although prior work has supported the importance of reducing glenohumeral internal rotation deficits in pitchers, this study demonstrates that deficits in shoulder ER and flexion are more significant predictors of subsequent elbow injury. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Axillary artery thrombosis in a major league baseball pitcher: a case report and rehabilitation guide.

This case study describes a Major League Baseball player who was diagnosed with an axillary artery thrombosis due to arterial compression from throwing. The purpose of this article is to create awareness as to the signs and symptoms associated with arterial positional compression and the rehabilitative implications to surgical intervention.