Chronic Adaptation of the Coracohumeral Space and Subscapularis Tendon in Professional Baseball Pitchers.

BACKGROUND: Pitchers frequently experience anterior shoulder pain, possibly associated with coracohumeral impingement; however, whether the coracohumeral distance (CHD) and/or subscapularis tendon adapt chronically (bilateral difference) due to pitching, and whether clinical measures are associated with CHD and subscapularis tendon organization have not been evaluated in professional pitchers. HYPOTHESIS: The authors hypothesized that dominant arm CHD would be smaller than the nondominant arm, dominant subscapularis tendon would have increased spatial frequency (ie, be more disorganized), and humeral retroversion (HR) would predict CHD and subscapularis tendon organization. LEVEL OF EVIDENCE: Level 4. METHODS: Healthy professional baseball pitchers were recruited during their preseason physical examination. Bilateral diagnostic ultrasound measured CHD, HR, and posterior capsule thickness (PCT), and quantified subscapularis tendon organization. External rotation, neutral, and crossbody CHD was measured. RESULTS: Overall, 52 healthy professional baseball pitchers participated. The dominant arm of pitchers demonstrated a significantly narrower CHD in all 3 positions (P < 0.01), increased scapular protraction (163 vs 156 mm; P < 0.01), and increased spatial frequency of the subscapularis tendon (1.8 vs 1.6 peaks/mm; P < 0.01). HR was associated with CHD in 30° of external rotation (R2 = 0.12; P < 0.01), neutral rotation (R2 = 0.11; P < 0.01), and the crossbody position (R2 = 0.28; P < 0.01). PCT was associated with CHD in 30° of external rotation (R2 = 0.16; P = 0.05). HR and CHD in 30° of external rotation was associated most strongly with subscapularis tendon organization (R2 = 0.11; P = 0.03). CONCLUSION: The dominant shoulder of professional pitchers presents with a smaller CHD, more scapular protraction, and more subscapularis tendon disorganization than the nondominant shoulder. CLINICAL RELEVANCE: Professional pitchers demonstrate chronic CHD and subscapularis tendon adaptations, which may increase their risk for anterior shoulder pain and subscapularis tendon injury.

Is There a Relationship Between Grip Strength and Injuries in Professional Baseball Players?

Background: Injuries in professional baseball players have become exceedingly common. Efforts to mitigate injury risk have focused on the kinetic chain, shoulder motion, and so forth. It is unclear whether grip strength is related to injury risk in professional baseball pitchers. Purpose/Hypothesis: The purpose of this study was to determine if grip strength was a risk factor for injury. It was hypothesized that pitchers with weaker grip strength would have a higher likelihood of sustaining a shoulder or elbow injury compared with pitchers with stronger grip strength. Study Design: Case-control study; Level of evidence, 3. Methods: All professional pitchers from a single Major League Baseball organization were included. Dominant and nondominant grip strength were measured after each pitching outing throughout the 2022 season. Injuries over the course of the season were recorded, and data were compared between pitchers who sustained a shoulder or elbow injury and those who did not. Results: Overall, 213 pitchers were included, of whom 53 (24.9%) sustained a shoulder or elbow injury during the season. The mean grip strength for all pitchers was 144.0 ± 20.8 lb (65.3 ± 9.4 kg). The mean dominant-arm grip strength was 142.6 ± 20.8 lb (64.7 ± 9.4 kg) for pitchers who did not sustain a shoulder or elbow injury and 148.2 ± 20.9 lb (67.2 ± 9.5 kg) for pitchers who did sustain an injury, with no significant group difference in grip strength (P > .05). Furthermore, there were no significant differences in change in grip strength over the course of the season between the groups. Conclusion: There was no significant difference in mean grip strength or change in grip strength over the course of a single season between professional baseball pitchers who sustained a shoulder or elbow injury and those who did not.