The Association of Sport Participation Behaviors with Throwing Arm Health in Little League Baseball Pitchers

Background: Little League shoulder (LLS) is an overuse injury characterized by throwing-related pain that commonly presents in adolescent male athletes. Investigations into the optimal duration of rest from throwing and protocols for graduated return to sports (RTS) are lacking. Purpose: To summarize the current literature with respect to the diagnosis, management, RTS, and return to throwing for LLS. Design: Systematic review; Level of evidence, 4. Methods: The databases EMBASE, MEDLINE, and PubMed were searched between inception and April 22, 2020. References of retrieved records were reviewed for potentially eligible studies. English-language studies that reported the diagnosis and/or management of LLS in children or adolescents were included. Studies of animals or cadavers, review articles, and non—peer reviewed records were excluded. Data were summarized narratively using descriptive statistics. Results: Overall, 23 studies (21 level 4 studies, 2 level 3 studies) met the criteria for a total of 266 participants with a weighted mean age of 12.8 years (range, 7.4-17 years). Treatment recommendations evolved from prolonged rest and complete cessation of throwing to shorter periods of rest and graduated RTS. Less than half (11/23) of studies reported specific criteria to RTS; 1 case report discussed a coaching strategy to resume throwing, and 1 case report discussed a regimented throwing program. The proportion of participants returning to any sport participation was 94.0% (n = 157/167). The proportion returning to their preinjury level of sport was 92.5% (n = 123/133). Upon RTS, 18.7% (n = 35/187) of participants experienced a recurrence of symptoms. Premature closure of the epiphysis was reported in 1 participant. Conclusion: Young athletes with LLS may return to play after a period of rest, and a high proportion return to their preinjury level of sport. Further prospective studies are warranted to develop evidence-based, graduated RTS protocols and to better capture any long-term sequelae of the condition.

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Biomechanics of the Shoulder in Youth Baseball Pitchers

The American Journal of Sports Medicine ◽

10.1177/0363546505275347 ◽

2005 ◽

Vol 33 (11) ◽

pp. 1716-1722 ◽

Cited By ~ 147

Author(s):

Michelle B. Sabick ◽

Young-Kyu Kim ◽

Michael R. Torry ◽

Michael A. Keirns ◽

Richard J. Hawkins

Keyword(s):

Body Weight ◽

External Rotation ◽

Pitching Motion ◽

Little League ◽

Youth Baseball ◽

Shoulder External Rotation ◽

Baseball Pitchers ◽

Force Components ◽

Simulated Game ◽

Distraction Force

Background The effects of repetitive throwing on the shoulders of developing athletes are not well understood because of the paucity of data describing the biomechanics of youth pitchers and the plasticity of the developing skeleton. Hypothesis The direction and magnitude of the stresses that exist at the proximal humeral physis during the fastball pitching motion are consistent with the development of proximal humeral epiphysiolysis (Little League shoulder) and/or humeral retrotorsion. Study Design Descriptive laboratory study. Methods A total of 14 elite youth baseball pitchers (mean age, 12.1 ± 0.4 years) were filmed from the front and dominant side while throwing fastballs in a simulated game. The net force and torque acting on the humerus throughout the throwing motion were calculated using standard biomechanical techniques. Results The external rotation torque about the long axis of the humerus reached a peak value of 17.7 ± 3.5 N.m (2.7% ± 0.3% body weight × height) just before maximum shoulder external rotation. A shoulder distraction force of 214.7 ± 47.2 N (49.8% ± 8.3% body weight) occurred at, or just after, ball release. Conclusion Shear stress arising from the high torque late in the arm-cocking phase is large enough to lead to deformation of the weak proximal humeral epiphyseal cartilage, causing either humeral retrotorsion or proximal humeral epiphysiolysis over time. The stresses generated by the external rotation torque are much greater than those caused by distraction forces generated during the pitching motion of youth baseball pitchers. Clinical Relevance The motion of throwing fastballs by youth baseball pitchers results in force components consistent with proposed mechanisms for 2 clinical entities.

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Opening of the Season: Little League Baseball Pro and Con

PEDIATRICS ◽

10.1542/peds.50.2.341 ◽

1972 ◽

Vol 50 (2) ◽

pp. 341-341

Author(s):

Harold M. Maller

Keyword(s):

Little League ◽

Arm Injuries ◽

Baseball Pitchers ◽

February Issue

Drs. Torg et al. have thrown us a curve with their article in the February issue of Pediatrics on arm injuries in young baseball pitchers. Having referred to "the effect of competitive pitching" in their title, they have proceeded to discuss a group of boys who, they would have us believe, played baseball "for the sake of recreation rather than competition." If one could imagine that such a group of boys had been found, then the authors have failed to investigate what they claim to have investigated.

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An Introduction to the Sport Commitment Model

Journal of Sport and Exercise Psychology ◽

10.1123/jsep.15.1.1 ◽

1993 ◽

Vol 15 (1) ◽

pp. 1-15 ◽

Cited By ~ 230

Author(s):

Tara K. Scanlan ◽

Paul J. Carpenter ◽

Jeffery P. Simons ◽

Greg W. Schmidt ◽

Bruce Keeler

Keyword(s):

Theoretical Model ◽

Stepwise Regression ◽

Sport Participation ◽

Empirical Test ◽

Social Constraints ◽

Psychological State ◽

Sport Commitment ◽

Little League ◽

Model Components

This article introduces a sport-specific theoretical model of commitment. Sport commitment is defined as a psychological state representing the desire or resolve to continue sport participation. The Sport Commitment Model proposes that sport commitment is determined by sport enjoyment, involvement alternatives, personal investments, social constraints, and involvement opportunities. Greater sport enjoyment, personal investments, social constraints, involvement opportunities, and less attractive involvement alternatives are predicted to lead to higher levels of sport commitment. Constitutive definitions were established for each of the model's components, and questionnaire items were developed. Results from the first empirical test of the model conducted with girls (n = 95) and boys (n = 83) participating in a Little League program showed that the questionnaire items formed reliable scales. Correlational analyses demonstrated that several predictors were related to sport commitment as hypothesized. Stepwise regression findings revealed that sport enjoyment and personal investments were the dominant predictors of commitment for this sample. Together, these two model components accounted for 58% of the sport commitment variance.

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Associations between Years of Pitching Experience and Injury Precursors in a Cohort of Little League Baseball Pitchers

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000385053.48759.b5 ◽

2010 ◽

Vol 42 ◽

pp. 473

Author(s):

Johna K. Register-Mihalik ◽

Sakiko Oyama ◽

Stephen W. Marshall ◽

Frederick O. Mueller

Keyword(s):

Little League ◽

Baseball Pitchers

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Current Workload Recommendations in Baseball Pitchers: A Systematic Review

The American Journal of Sports Medicine ◽

10.1177/0363546519831010 ◽

2019 ◽

Vol 48 (1) ◽

pp. 229-241 ◽

Cited By ~ 1

Author(s):

Neil K. Bakshi ◽

Paul M. Inclan ◽

Jacob M. Kirsch ◽

Asheesh Bedi ◽

Cristine Agresta ◽

...

Keyword(s):

High School ◽

Systematic Review ◽

Injury Rate ◽

Current Evidence ◽

Professional Baseball ◽

High Quality Research ◽

Baseball Players ◽

Little League ◽

Increased Risk ◽

Baseball Pitchers

Background: Several recommendations have been made regarding pitch counts and workload for baseball players of different levels, including Little League, high school, collegiate, and professional baseball. However, little consensus is found in the literature regarding the scientific basis for many of these recommendations. Purpose: The primary purpose of this study was to summarize the evidence regarding immediate and long-term musculoskeletal responses to increasing pitching workload in baseball pitchers of all levels. A secondary purpose of this review was to evaluate the extent to which workload influences injury and/or performance in baseball pitchers. Study Design: Systematic review. Methods: We performed a systematic search in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for studies addressing physiologic and/or pathologic musculoskeletal changes in response to a quantifiable pitching workload. We included studies examining the effects of pitching workload on performance, injury rate, and musculoskeletal changes in Little League, high school, collegiate, and professional baseball players. Results: We identified 28 studies that met our inclusion and exclusion criteria: 16 studies regarding Little League and high school pitchers and 12 studies regarding collegiate and professional pitchers. The current evidence presented suggests that increased pitching workload may be associated with an increased risk of pain, injury, and arm fatigue in Little League and high school pitchers. However, little consensus was found in the literature regarding the association between pitching workload and physiologic or pathologic changes in collegiate and professional pitchers. Conclusion: Evidence, although limited, suggests the use of pitch counts to decrease injury rates and pain in Little League and high school baseball pitchers. However, further research must be performed to determine the appropriate number of pitches (or throws) for players of different ages. This systematic review reported conflicting evidence regarding the use of pitch counts in college and professional baseball. Future high-quality research is required to determine the role, if any, of pitch counts for collegiate and professional pitchers.

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