Assessing Biomechanical and Clinical Outcomes of an Elbow Orthosis Intervention in Youth Baseball: Preliminary Results

Proper orthosis design may help youth baseball players develop safer pitching mechanics to prevent elbow injuries. This study evaluated the impact of a custom elbow orthosis on pitching biomechanics and adverse events. Ten 11-12-year-old players (mean age 11.5 years) from a regional league team were recruited. The inclusion criteria were at least two years of baseball experience. Six players were randomly assigned to the orthosis group, with four in the control group. Anthropometric data and baseline characteristics were recorded. A video analysis assessed elbow flexion angle during pitching at baseline and at 2 months. The frequency of orthosis wear was also tracked. Adverse events during twice-weekly practices were documented. Post-study surveys evaluated orthosis comfort, stability, and safety perceptions. In the orthosis group (n = 6), four participants showed improved elbow flexion angle, and two of the six participants showed almost no change. The overall median difference was 23.5°. In the control group (n = 4), three participants showed improvement, with a median improvement of 5.5°. Twelve adverse events, including pain, were reported by players not wearing orthoses, whereas no events occurred with orthosis use. Individual players in the control group or who did not wear the orthosis correctly experienced multiple episodes of pain from pitching over the study period. This preliminary study indicates a custom elbow orthosis can optimize pitching biomechanics and prevent adverse events in youth baseball players over the course of two months.

Effect of Pitching Restrictions and Mound Distance on Youth Baseball Pitch Counts

Background:

Studies have shown that higher pitch counts are directly related to a greater incidence of elbow and shoulder pain among youth baseball pitchers.

Purpose/Hypothesis:

The purpose of this study was to examine the effect of different pitching restriction rules on the number of pitches thrown in youth baseball leagues. We hypothesized that more pitches would be thrown in leagues with inning restrictions versus leagues with pitch count restrictions as well as in leagues with a longer mound distance (from pitching mound to home plate).

Study Design:

Cohort study; Level of evidence, 2.

Methods:

Pitch count data were collected for 2 consecutive years over a 10-week season from 3 different leagues of 9- to 12-year-old baseball players in a single city. The Eastern league had a pitch count restriction and 46-ft (14.02-m) mound distance. The Southeastern and South leagues’ pitching restrictions were based on innings per week. The Southeastern league had a 50-ft (15.24-m) mound distance, while the South league had a 46-ft mound distance. Comparisons of total seasonal pitches thrown were made of the 3 highest-volume pitchers on each team. League averages for each value were then compared utilizing analysis of variance with Bonferroni post hoc analysis. The number of pitchers in each league who threw >600 pitches per season was compared using the chi-square test.

Results:

No significant difference in seasonal pitch counts or innings pitched was noted between the Eastern and South leagues, which differed only in their pitching restrictions. The Southeastern league, with a longer mound distance, was found to have higher seasonal pitch counts per thrower (598 ± 195 pitches) than the South league (463 ± 198 pitches) for the 3 highest-volume throwers for each team (P = .004). The Southeastern league also had a significantly larger number of pitchers who threw >600 pitches per season (33 vs 20 for Eastern and 13 for South; P = .009).

Conclusion:

There was no significant difference in seasonal pitch counts when the leagues in this study differed based on pitching restrictions. However, the league with a greater mound distance (Southeastern) had higher seasonal pitch counts for the highest-volume throwers. Pitching restrictions based on pitch counts, as opposed to innings, may be advisable.

Pitching Behaviors in Youth Baseball: Comparison With the Pitch Smart Guidelines

Background

The Pitch Smart guidelines aim to limit youth baseball pitching behaviors associated with overuse injuries. Despite many youth baseball leagues being compliant with the guidelines, during tournaments, pitch count restrictions or guidelines are often not followed.

Purpose

To perform a quantitative analysis of pitch counts in youth baseball players and evaluate compliance with regard to the Pitch Smart guidelines in the tournament setting.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Included in the analysis were 100 youth baseball teams that competed in the 8-and-under to 14-and-under age divisions during the 2019 tournament season. Pitching data were compared with the Pitch Smart guidelines. Violations were identified as (1) exceeding maximum daily pitch count, (2) inadequate rest between pitching events, and (3) pitching more than 1 event on the same day. Pitcher and game factors were analyzed for possible relationships to guideline violations using mixed-effects negative binomial regression models, with comparisons of violations using rate ratios (RRs).

Results

Analysis included 1046 pitchers and 2439 games. There were 1866 total Pitch Smart guideline violations, with 48.6% of pitchers having at least 1 violation. Inadequate rest was the most common reason for violation, with noncompliance occurring in 43.3% of pitchers. The highest rate of any violation (0.32 per appearance) occurred in the 8-and-under age division. High-volume pitchers had increased violation rates in each category compared with low-volume pitchers (P < .001). Violation rates were increased more than twice the rate when pitchers participated in ≥5 consecutive games without a rest day when compared with a single game (RR, 2.48; P < .001).

Conclusion

Noncompliance with Pitch Smart guidelines in tournament settings occurred in more than 90% of teams and almost half of all pitchers. Factors associated with noncompliance included younger pitcher age, high-volume pitching, and pitching in multiple consecutive games. Education of tournament directors, coaches, parents, and athletes regarding pitching guidelines is warranted in order to limit the risk of injury.

Medical Advisability of Youth Pitching Recommendations on the Internet

Background:

As the incidence of youth pitching injuries and surgical procedures attributed to overuse has drastically increased, there are quality concerns about popular internet resources regarding arm care for youth pitchers.

Purpose/Hypothesis:

To assess the medical advisability of online arm care recommendations for youth pitchers. It was hypothesized that websites contain misleading arm-care information that is discordant with medical advice.

Study Design:

Cross-sectional study.

Methods:

We reviewed the first 100 websites populated after a Google search for youth pitching recommendations. Websites were categorized by type (athletic organization, commercial, or educational) and content quality (medically advisable, discordant, or neutral), the latter with respect to the Pitch Smart guidelines used by Major League Baseball. Chi-square tests of independence and z tests of independent proportions were used to compare column proportions among categories of website content quality for each type of website source. Given the small sample sizes in some instances, the Fisher-Freeman-Halton exact test was performed to assess the relationship between website source type and quality of information.

Results

Of the 99 qualifying websites, 76 were categorized as medically advisable, 16 as discordant, and 7 as neutral. In addition, 92% of educational websites and 94.7% of athletic organization websites featured exclusively advisable content, whereas only 54.8% of commercial websites were advisable. Of the 16 discordant websites, 15 were commercial sites. Educational websites were significantly more advisable and neutral in content when compared with discordant information, while commercial websites were significantly predictive of discordant content. Among the first 50 websites populated according to Google, 42 (84%) were advisable, 6 (12%) discordant, and 2 (4%) neutral. The remaining websites (n = 49) featured 34 (69.4%) that were advisable, 10 (20.4%) discordant, and 5 (10.2%) neutral.

Conclusion:

Study findings indicated that websites of an educational nature are predictive of medically advisable content, while commercial websites (eg, blogs) are associated with discordant information. The abundance and availability of inaccurate internet information should be appreciated by medical professionals and parents/coaches of youth baseball players.

The Father in Youth Baseball: A Self-Determination Theory Approach

This study based on the self-determination theory aims to examine the relationship among the aspirations that fathers have about their children's youth baseball practice, the children's basic psychological needs (satisfaction and frustration), and their intentions to either continue or drop out of baseball practice in a sample of children from Hermosillo, Mexico. A cross-sectional study was carried out involving 533 fathers (M = 44.30, SD = 5.18) and 533 children (M = 13.09, SD = 1.68). The results showed that the intrinsic aspirations of fathers were positively correlated to the satisfaction of the children's psychological needs, whereas the extrinsic aspirations of fathers were positively correlated with the frustration of the children's psychological needs. Satisfaction of basic psychological needs was positively correlated with the intention to continue and negatively correlated with dropout; on the contrary, frustration of basic psychological needs was negatively correlated with the intention to continue and positively with dropout. In conclusion, the fathers' pursuit of intrinsic aspirations for their children in the youth baseball context satisfies the children's basic psychological needs, and in turn, their intention to continue practicing increases. Conversely, when a father pursues extrinsic aspirations for his son in youth baseball, the child will feel his basic psychological needs frustrated, and he will have a greater intention to drop out. Overall, this study extends the existing sport-scientific literature by confirming the impact of parents' aspirations on their children's basic psychological needs and intention to continue being baseball players.

Early Sport Specialization Linked to Throwing Arm Function and Upper Extremity Injury History in College Baseball Players

BACKGROUND

Evidence suggests that shoulder and elbow injuries account for 31% to 37% of all National Collegiate Athletic Association (NCAA) baseball injuries, and up to 69% of NCAA baseball injuries are the result of noncontact and overuse mechanisms. Early sport specialization may contribute to the high rates of upper extremity injuries in college baseball players.

HYPOTHESIS

Higher specialization by age 13 years would be associated with worse subjective throwing arm function and a greater history of shoulder and elbow injury.

STUDY DESIGN

Cohort study.

LEVEL OF EVIDENCE

Level 2.

METHODS

Survey data were collected from college baseball players (N = 129) during midseason of the spring 2019 baseball season. Participants were stratified in low, moderate, and high specialization groups based on a 3-criteria sports specialization questionnaire. Participants' throwing arm function was measured using the Functional Arm Scale for Throwers and the Kerlan-Jobe Orthopaedic Clinic shoulder and elbow questionnaires. Participants' history of a shoulder or elbow injury that resulted in missing ≥2 weeks of baseball activity at any point in their baseball career was also collected.

RESULTS

The high specialization group reported worse subjective throwing arm function on the Functional Arm Scale for Throwers questionnaire than the low (P = 0.03) and moderate (P = 0.01) specialization groups. The high specialization group was over 5 times more likely to report a history of shoulder injury than the moderate (odds ratio [OR] = 5.42; 95% CI [1.71, 17.2]; P = 0.004) and low (OR = 5.20; 95% CI [1.87, 14.5]; P = 0.002) specialization groups, and over 3 times more likely to report a history of elbow injury than the moderate specialization group (OR = 3.77; 95% CI [1.05, 13.6]; P = 0.04).

CONCLUSION

College baseball players that were highly specialized by age 13 years reported worse subjective throwing arm function and were more likely to have a history of upper extremity injury than players that were moderate or low specialization.

CLINICAL RELEVANCE

Early specialization in baseball may be detrimental to long-term upper extremity health in college baseball players.

Sport Specialization and Increased Injury Frequency in Youth Baseball Players: A Prospective Study

CONTEXT

Sport specialization is thought to be a primary contributor to the throwing-related injury risk in youth baseball players.

OBJECTIVE

To (1) establish arm-injury incidence in a cohort of male youth (9-12 years old) baseball players and (2) examine sport specialization and the frequency of arm injuries in the same cohort.

DESIGN

Cohort study.

SETTING

Greenville, South Carolina, youth baseball programs and tournaments.

PATIENTS OR OTHER PARTICIPANTS

A total of 159 asymptomatic youth baseball players (age = 11.1 ± 1.1 years) were physically assessed and then were prospectively followed for 6.7 ± 1.5 months.

MAIN OUTCOME MEASURE(S)

Athlete demographics and playing and injury histories were initially recorded. Athlete-exposures and presence of arm injury were prospectively tracked. All injuries were physically confirmed by a licensed physical therapist.

RESULTS

Youth players demonstrated an arm-injury incidence rate of 2.22 per 1000 athlete-exposures. Parents and players underestimated sport-specialization status based on the standard research definition (self versus research based: 31% versus 83%, respectively; P = .001). The frequency of arm injuries was higher in specialized players (100%) than in nonspecialized players (80%, P = .03) but did not differ between pitchers and position players (13.2% each, P = 1.00).

CONCLUSIONS

Sport specialization was associated with throwing-related arm injuries in a small cohort of youth baseball players. It is concerning that 57.9% of parents and specialized players were unaware of the athletes' status. Larger studies with longer follow-up periods are needed to further evaluate injury-risk profiles in physically developing youth populations.

Impact of ball weight on medial elbow torque in youth baseball pitchers

HYPOTHESIS

Our hypothesis was that an increase in ball weight would result in an increase in medial elbow torque during the pitching motion.

METHODS

Youth pitchers were recruited for this study and instructed to throw 5 maximum-effort fastballs from ground level using baseballs of 4 different weights: 85 g (3 oz), 113 g (4 oz), 142 g (5 oz), and 170 g (6 oz). The validated Motus sensor was used to assess medial elbow torque, arm speed, arm slot, and shoulder rotation for each pitch. Pitch velocity was measured using a radar gun. Relationships between baseball weight and pitching kinetics and/or kinematics were evaluated using linear mixed-effects analysis. An exit survey was conducted detailing the pitcher's evaluation of the ball weights used.

RESULTS

A total of 19 youth baseball pitchers (average age, 11.8 ± 1.1 years; age range, 9-14 years) completed the study. For every 1-oz (28-g) increase in ball weight, ball velocity decreased 2.0 ± 0.1 mph (χ² = 52.68, P < .001), medial elbow torque increased 0.92 ± 0.37 newton meters (χ² = 5.36, P = .02), and arm speed decreased 8.52 ± 3.68 rpm (χ² = 5.03, P = .02). Shoulder rotation and arm slot were not significantly impacted by ball weight (P > .05). Survey results indicated that the 85-g (3-oz) baseball was most favored (8 of 19 pitchers) and believed to result in the highest pitch velocity (15 of 19 pitchers). The 170-g (6-oz) baseball was least favored (17 of 19 pitchers) and believed to result in the slowest pitch velocity (18 of 19 pitchers). No adverse outcomes were reported with the use of any ball weight or the mobile sensor.

CONCLUSION

Among youth pitchers, an increase in ball weight correlated with greater medial elbow torque, decreased pitch velocity, and decreased arm speed.

Shoulder MRI Abnormalities in Asymptomatic Little League Baseball Players

Background:

Youth baseball is extremely popular in the United States, but it has been associated with shoulder pain and injury. The incidence of shoulder abnormalities in this athletic population has yet to be defined.

Purpose:

To examine abnormalities noted on magnetic resonance imaging (MRI) in the shoulders of asymptomatic Little League baseball players and to correlate these findings with the players’ throwing history and physical examinations.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

A total of 23 Little League baseball players aged 10 to 12 years were recruited. All players underwent a comprehensive physical examination and responded to a questionnaire addressing their playing history and any arm or shoulder pain. Bilateral shoulder MRIs were performed and read in a blinded manner by 2 radiologists. Responses on the questionnaire and physical examination findings were compared between participants with and without positive MRI findings through use of chi-square test and analysis of variance.

Results:

The dominant arm was 8.5 times more likely to have an abnormality on MRI compared with the nondominant arm. In all, 12 players (52%) had 17 positive MRI findings in their throwing shoulder that were not present in their nondominant shoulder. These findings included edema or widening of the proximal humeral physis (n = 5), labral tear (n = 4), partial rotator thickness tear (n = 4), acromioclavicular joint abnormality (n = 2), subacromial bursitis (n = 1), and cystic change of the greater tuberosity (n = 1). Two primary risk factors were associated with an abnormal MRI: year-round play and single-sport athletes focusing solely on baseball (P < .05). Players with no risk factors, 1 risk factor, and both risk factors had a 25%, 71%, and 100% chance, respectively, of having an abnormal MRI. A majority of players (61%) had previously experienced shoulder pain, especially pitchers throwing curveballs and sliders (P < .05), but this was not associated with an abnormal MRI.

Conclusion:

Abnormalities seen on MRI involving the shoulder are common in Little League baseball players, especially those who are single-sport athletes playing year-round.

Youth Baseball Pitching Mechanics: A Systematic Review

Context:

Pitching injuries in youth baseball are increasing in incidence. Poor pitching mechanics in young throwers have not been sufficiently evaluated due to the lack of a basic biomechanical understanding of the “normal” youth pitching motion.

Objective:

To provide a greater understanding of the kinetics and kinematics of the youth baseball pitching motion.

Data Sources:

PubMed, MEDLINE, and SPORTDiscus databases were searched from database inception through February 2017.

Study Selection:

A total of 10 biomechanical studies describing youth pitching mechanics were included.

Study Design:

Systematic review.

Level of Evidence:

Level 3.

Data Extraction:

Manual extraction and compilation of demographic, methodology, kinetic, and kinematic variables from the included studies were completed.

Results:

In studies of healthy youth baseball pitchers, progressive external rotation of the shoulder occurs throughout the start of the pitching motion, reaching a maximum of 166° to 178.2°, before internally rotating throughout the remainder of the cycle, reaching a minimum of 13.2° to 17°. Elbow valgus torque reaches the highest level (18 ± 4 N·m) just prior to maximum shoulder external rotation and decreases throughout the remainder of the pitch cycle. Stride length is 66% to 85% of pitcher height. In comparison with a fastball, a curveball demonstrates less elbow varus torque (31.6 ± 15.3 vs 34.8 ± 15.4 N·m).

Conclusion:

Multiple studies show that maximum elbow valgus torque occurs just prior to maximum shoulder external rotation. Forces on the elbow and shoulder are greater for the fastball than the curveball.

Are the Current Little League Pitching Guidelines Adequate? A Single-Season Prospective MRI Study

Background:

Little League throwing guidelines have recently been implemented in an attempt to lessen the growing number of elbow injuries occurring in youth baseball players.

Hypothesis/Purpose:

The purpose of this study was to examine pre- and postseason changes seen on magnetic resonance imaging (MRI) in youth baseball players’ elbows in an attempt to identify risk factors for pain and MRI abnormalities, with a particular focus on the current Little League guidelines. We hypothesized that MRI abnormalities would be common in pitchers with high pitch counts and poor guideline compliance.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

A prospective study of Little League players aged 10 to 13 years was performed. Players were recruited prior to the start of the season and underwent bilateral elbow MRI as well as a physical examination and completed a questionnaire addressing their playing history and arm pain. At the end of the season, a repeat MRI and physical examination were performed. MRIs were read by blinded radiologists. During the season, player statistics including innings played, pitch counts, and guideline compliance were recorded. Physical examination findings and player statistics were compared between subjects with and without MRI changes utilizing chi-square and analysis of variance techniques.

Results:

Twenty-six players were enrolled. Despite 100% compliance with pitching guidelines, 12 players (48%) had abnormal MRI findings, and 28% experienced pain during the season. There was a significant difference in distal humeral physeal width measured pre- to postseason (1.54 vs 2.31 mm, P < .001). There was a significant loss of shoulder internal rotation during the season, averaging 11°. While pitch counts, player position, and throwing curveballs/sliders were not significantly associated with changes seen on MRI, year-round play was associated with abnormalities (P < .05). Much lower compliance (<50%) was observed with nonenforced guidelines, including avoidance of single-sport specialization, year-round play, and throwing curveballs/sliders.

Conclusion:

Arm pain and MRI abnormalities of the medial elbow are common in Little League baseball players who comply with the Little League throwing guidelines, especially those playing year-round.

The Youth Throwing Score: Validating Injury Assessment in Young Baseball Players

BACKGROUND

Epidemic levels of shoulder and elbow injuries have been reported recently in youth and adolescent baseball players. Despite the concerning frequency of these injuries, no instrument has been validated to assess upper extremity injury in this patient population. Purpose/Hypothesis: The purpose of this study was to validate an upper extremity assessment tool specifically designed for young baseball players. We hypothesized that this tool will be both reliable and valid.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

The Youth Throwing Score (YTS) was constructed by an interdisciplinary team of providers and coaches as a tool to assess upper extremity injury in youth and adolescent baseball players (age range, 10-18 years). The psychometric properties of the test were then determined.

RESULTS

A total of 223 players completed the final survey. The players' mean age was 14.3 ± 2.7 years. Pilot analysis showed that none of the 14 questions received a mean athlete importance rating less than 3 of 5, and the final survey read at a Flesch-Kincaid level of 4.1, which is appropriate for patients aged 9 years and older. The players self-assigned their injury status, resulting in a mean instrument score of 59.7 ± 8.4 for the 148 players "playing without pain," 42.0 ± 11.5 for the 60 players "playing with pain," and 40.4 ± 10.5 for the 15 players "not playing due to pain." Players playing without pain scored significantly higher than those playing with pain and those not playing due to pain ( P < .001). Psychometric analysis showed a test-retest intraclass correlation coefficient of 0.90 and a Cronbach alpha intra-item reliability coefficient of 0.93, indicating excellent reliability and internal consistency. Pearson correlation coefficients of 0.65, 0.62, and 0.31 were calculated between the YTS and the Pediatric Outcomes Data Collection Instrument sports/physical functioning module, the Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow score, and the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, respectively. Injured players scored a mean of 9.4 points higher after treatment ( P < .001), and players who improved in their self-assigned pain categorization scored 16.5 points higher ( P < .001).

CONCLUSION

The YTS is the first valid and reliable instrument for assessing young baseball players' upper extremity health.

Youth Baseball Pitching Stride Length: Normal Values and Correlation With Field Testing

BACKGROUND

Pitching biomechanical analysis has been recommended as an important component of performance, injury prevention, and rehabilitation. Normal values for youth pitching stride length have not been established, leading to application of normative values found among professional pitchers to youth pitchers.

HYPOTHESES

The average youth pitching stride length will be significantly less than that of college and professional pitchers. There will be a positive correlation between stride length, lower extremity power, balance, and pitching experience.

STUDY DESIGN

Prospective cohort study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Ninety-two youth baseball pitchers (aged 9-14 years) met the inclusion/exclusion criteria and completed the study. Stride length was recorded using a Dartfish video system over 3 maximal effort pitches. Both intra- and interrater reliability was calculated for the assessment of stride length. Double-leg vertical jump, single-leg stance time, leg length, weight, age, and pitching experience were also recorded.

RESULTS

Mean (SD) stride length was 66.0% (7.1%) of height. Stride length was correlated ( P < 0.01) with vertical jump (0.38), pitching experience (0.36), and single-leg balance (0.28), with excellent intra- and interrater reliability (0.985 or higher). No significant correlations between stride length and body weight, leg length, or age existed.

CONCLUSIONS

There was a significant difference between youth pitching stride length and the current published norms for older and more elite throwers. There was a positive correlation between stride length and lower extremity power, pitching experience, and single-leg balance.

CLINICAL RELEVANCE

Two-dimensional analysis of stride length allows for the assessment of pitching biomechanics in a practical manner. These values can be used for return to pitching parameters after an injury and designing injury prevention and performance programs.

Elbow Biomechanics of Pitching: Does Age or Experience Make a Difference?

BACKGROUND

Elbow pain and elbow injuries are common in youth baseball players. It is not clear whether pitching experience and/or age creates biomechanical differences at the elbow and whether these differences place an athlete at greater risk.

HYPOTHESES

(1) Youth pitchers will have differing elbow kinematics with regard to flexion/extension, internal/external rotation, and pronation/supination when compared with nonbaseball athletes and (2) younger youth pitchers will have differing elbow kinematics when compared with older youth pitchers.

STUDY DESIGN

Case-control study.

LEVEL OF EVIDENCE

Level 4.

METHODS

Twenty-seven healthy male youths age 10 to 18 years were recruited and divided into an experience group (n = 18 pitchers) and a no experience group (n = 9 nonbaseball athletes). The experience group was subdivided by age into the younger experience subgroup (n = 10 pitchers) and the older experience subgroup (n = 8 pitchers). Biomechanics were recorded using an electromagnetic motion tracking system. Subjects from each group were averaged together, and a Mann-Whitney U test was utilized for statistical analysis.

RESULTS

The experience group had greater external rotation during late cocking (-47.8° vs 5.8°) and greater flexion during early cocking (112.8° vs 100.1°). The younger experience subgroup had greater range of motion with supination-pronation during early cocking (21.9° vs 11.2°) and late cocking (5.9° vs 2.0°).

CONCLUSION

Youth athletes with pitching experience had an increase in maximal external rotation in late cocking and maximal flexion in early cocking, which suggests experience may be a factor to these parameters. The age of experienced baseball pitchers may be a factor due to differences observed with supination and pronation.

CLINICAL RELEVANCE

Learning to throw is a skill that leads to changes in elbow motion; however, these changes may be stable once athletes reach grade school age. Minimal differences were noted between the younger and older experience subgroups, which may underscore the importance of teaching proper mechanics at a young age.

Arm pain in youth baseball players: a survey of healthy players

BACKGROUND

Overuse injury in youth baseball players is increasing in prevalence, and these injuries have been correlated to pitching mechanics and pitch counts/types. Prior studies regarding arm pain in these athletes have focused simply on presence or absence of pain during the season rather than on detailed factors related to arm pain with respect to frequency, severity, and associated performance and psychosocial effect.

HYPOTHESIS/PURPOSE

The goal of this study was to investigate frequency, quality, and effect of arm pain in healthy youth baseball players. The hypothesis was that arm pain will affect a majority of healthy baseball players and will be associated with adverse psychosocial effects.

STUDY DESIGN

Descriptive epidemiological study.

METHODS

A novel survey focusing on arm pain in youth baseball players was developed for the purpose of this study. Survey questions were formulated by a consortium of trainers, clinicians, and coaches. Surveys were administered to healthy youth baseball players throughout the states of New Jersey and New York.

RESULTS

A total of 203 healthy players completed the survey; 23% of players (n=47) reported a prior overuse injury. Only 26% and 20% of players reported that their arm never hurt when throwing or the day after throwing, respectively; 30% of players reported that arm pain at least sometimes caused them to have less fun playing; and 46% of players reported at least once being encouraged to keep playing despite having arm pain. Pitchers were more likely to report arm pain while throwing and the day after throwing and to indicate that arm pain held them back from being a better player (all P<.05). Those with prior overuse injury were more likely to have arm pain while throwing, to have arm fatigue during a game or practice, and to be encouraged to keep playing despite having pain (all P<.05).

CONCLUSION

A majority of healthy (actively competing) youth baseball players report at least some baseline arm pain and fatigue, and many players suffer adverse psychosocial effects from this pain.

Risk-Prone Pitching Activities and Injuries in Youth Baseball: Findings From a National Sample

BACKGROUND

There are relatively few published epidemiological studies that have correlated pitching-related risk factors with increased pitching-related arm problems as well as injuries.

HYPOTHESIS

High pitching volume and limited recovery will lead to arm fatigue, thus placing young pitchers at a greater risk for elbow and shoulder problems and, subsequently, an increased risk for arm injuries.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A national survey was conducted among 754 youth pitchers (ages 9 to 18 years) who had pitched in organized baseball leagues during the 12 months before the survey. Self-reported risk-prone pitching activities were identified and compared with recommendations by the American Sports Medicine Institute. Relationships between self-reported pitching activities, shoulder and elbow problems, and injuries were assessed using multivariable logistic regression.

RESULTS

Of the 754 participating pitchers, 43.4% pitched on consecutive days, 30.7% pitched on multiple teams with overlapping seasons, and 19.0% pitched multiple games a day during the 12 months before the study. Pitchers who engaged in these activities had increased risk of pitching-related arm pain (odds ratio [OR] = 2.53, 95% confidence interval [CI] = 1.14-5.60; OR = 1.85, 95% CI = 1.02-3.38; OR = 1.89, 95% CI = 1.03-3.49, respectively). Nearly 70% of the sample reported throwing curveballs, which was associated with 1.66 (95% CI = 1.09-2.53) greater odds of experiencing arm pain while throwing. Pitching-related arm tiredness and arm pain were associated with increased risk of pitching-related injuries. Specifically, those who often pitched with arm tiredness and arm pain had 7.88 (95% CI = 3.88-15.99) and 7.50 (95% CI = 3.47-16.21) greater odds of pitching-related injury, respectively. However, pitching on a travel baseball club, playing baseball exclusively, or playing catcher were not associated with arm problems.

CONCLUSION

The results of this study, along with those of others, reinforce the importance of avoiding risk-prone pitching activities to prevent pitching-related injuries among youth pitchers.