Limited total arc range of motion increases sheer stress in the shoulder while pitching in collegiate baseball pitchers.

CONTEXT: Upper extremity injuries in baseball pitchers cause significant time-loss from competing and decreased quality of life. Although shoulder range of motion (ROM) is reported as a key factor to prevent potential injury, it remains unclear how limited glenohumeral ROM affects pitching biomechanics which may contribute to upper extremity injuries. OBJECTIVE: To investigate how pitchers with decreased total arc glenohumeral ROM of the throwing arm differed in upper extremity pitching kinematics and kinetics as well as ball velocity compared to pitchers with greater levels of glenohumeral ROM. DESIGN: Cross-sectional Study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Fifty-seven baseball pitchers (ages 18-24) were divided into either control (≧160° total arc) or lower ROM (<160° total arc) groups. MAIN OUTCOME MEASURE(S): The mean glenohumeral ROM deficits, pitching kinematic and kinetic outcomes, and ball velocity were compared between groups. RESULTS: The control group demonstrated significantly less deficit in total arc ROM between arms than the lower ROM (Control: -1.5±10.0°, Lower ROM: -12.4±13.9°, p<.001). While, the lower ROM group displayed less maximal shoulder external rotation (ER) while pitching, the control group had significantly less difference in ROM between maximal shoulder ER while pitching and clinically-measured ER (Lower ROM: 64.4±12.1°, Control: 55.8±16.6°, p=.025). The control group had significantly faster ball velocity compared to the lower ROM group (Control: 85.0 ± 4.3mph, Lower ROM: 82.4 ± 4.8mph, p=.024). CONCLUSION: Pitchers with decreased total arc glenohumeral ROM (<160° total arc) may undergo over-stretching toward ER in the shoulder during the late cocking phase. Pitchers with higher total arc ROM can pitch the same or faster ball without increasing loading in the upper extremity. Total arc glenohumeral ROM measurement can be a clinical screening tool to monitor shoulder condition over the time, and pitchers with limited total arc ROM might be at higher risk of shoulder injury.

Motivation and Behaviors Related to Sport Specialization in College Baseball Players.

CONTEXT: Early sport specialization is a growing concern among youth sports athletes, particularly in baseball. Motivation to participate in sports is an important factor in determining which sports youth athletes participate in and why. OBJECTIVE: The purpose of this study was to qualitatively investigate youth sport participation behaviors and motivations of college baseball players. DESIGN: Qualitative Study. SETTING: Online Teleconference. PATIENTS OR OTHER PARTICIPANTS: We conducted 25 semi-structured interviews with college baseball athletes who were classified as either high-level (n=8), moderate-level (n=9), or low-level specialists (n=8) prior to college. DATA COLLECTION AND ANALYSIS: Participants completed an individual semi-structured interview to develop an understanding of the participants' youth and high school sports experiences and associated motivations to participate in those experiences. A framework analysis approach was used to analyze transcript data to identify themes among the three specialization groups. RESULTS: From our interview analysis, six overall themes emerged among the groups: (1) Motivation, (2) Stress, (3) Quitting, (4) Barriers, (5) Facilitators of Success, and (6) Future Directions. Moderate and high-level specialists described higher levels of passion, participating in deliberate practice, higher levels of performance-related stress, and a desire to quit sports more than low-level specialists. None of the groups described parents as an overbearing external motivator to participate in sports at an early age. CONCLUSIONS: Participants who were classified as low-, moderate-, and high-level specialists described different experiences related to their motivation, stress levels, desire to quit, barriers to participating in baseball, facilitators of success, and their overall future career goals after completing baseball. This information may be useful for parents, coaches, and health care professionals to better communicate the benefits and risks associated with sport specialization to youth athletes. Future research is needed to determine if differences in motivation levels exist in younger populations.

Early Sport Specialization and Long-term Throwing Arm Health in College Baseball Players.

BACKGROUND: Early sport specialization is associated with increased risk of overuse injuries in several sports, including baseball. However, limited evidence exists evaluating how early sport specialization affects patient-reported outcome measures as they age. The purpose of this study was to determine differences in Kerlan-Jobe Orthopedic Clinic (KJOC) Shoulder and Elbow Scores among collegiate baseball players based on the grade when a participant first reported high specialization behaviors. HYPOTHESIS: Baseball players who were highly specialized at a younger age will have worse throwing arm health while participating in college. STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 3. METHODS: A total of 752 college baseball players was contacted through their institution's athletic trainer. We measured baseball specialization and KJOC scores using the validated Baseball and Sport Experience survey. Data were summarized using means and SDs, medians and interquartile ranges (IQRs), and frequencies and percentages. A Kruskal-Wallis test was used to determine differences in mean KJOC scale scores based on the earliest time the participant reported high-level specialization. RESULTS: A total of 294 baseball players completed the survey (response rate: 39.1%). Of the 294 participants, 280 completed the KJOC scale questions to generate a total KJOC score (median: 90.5; IQR: 76.6-97.2). No significant differences in KJOC total scores (P = 0.78) existed based on the grade period in which the athlete was first highly specialized. CONCLUSION: Early baseball specialization as a youth baseball player may not impact throwing arm health in college baseball athletes. CLINICAL RELEVANCE: Early specialization has been linked to increased risk for overuse injuries in certain sports, but may not lead to poorer throwing arm health in college baseball players. Sports medicine clinicians and researchers may use this information to educate various stakeholders about the benefits and risks associated with early sport specialization.

A Comparison of Pitching Biomechanics and Sport Specialization in High School Pitchers.

Background: The prevalence of sport specialization in high school athletes continues to rise, particularly among baseball players. Previous research has focused on the incidence of injury among specialized and non-specialized athletes but has yet to examine the level of sport specialization and pitching biomechanics. Hypotheses/Purpose: The purpose of this study was to investigate differences in pitching volume and biomechanics between low-, moderate-, and high-level specialized baseball pitchers. It was hypothesized that high-level specialized pitchers would have the most pitching volume within the current and previous years while low-level specialized pitchers would exhibit the least amount. The second hypothesis states that kinematics and kinetics commonly associated with performance and injury risk would differ between low-, moderate-, and high-level specialized pitchers. Study Design: Case-Control Study. Methods: Thirty-six high school baseball pitchers completed a custom sport specialization questionnaire before participating in a three-dimensional pitching motion analysis. Sport specialization was based off current guidelines and categorized as low-, moderate-, and high-level specialized based upon self-reported outcomes. Pitchers then threw ≈10 fastballs from a mound engineered to professional specifications. Data averaged across fastballs was used for biomechanics variables. Key pitching biomechanical and pitching volume variables were compared between low-, moderate-, and high-level specialized pitchers. Results: High-level specialized pitchers were older (p = 0.003), had larger body mass (p = 0.05) and BMI (p = 0.045), and threw faster (p = 0.01) compared to low-level specialized pitchers. Pitching volume and pitching biomechanics were similar across groups. Conclusions: Pitching biomechanics were similar across groups, although high-level specialized pitchers threw with significantly higher throwing velocity compared to low-level pitchers. The low amount of pitching volume throughout the season may be responsible for the lack of additional observed differences. Further research should examine the relationship between pitching biomechanics, upper extremity strength and flexibility, and sport specialization. Level of Evidence: Level III.