Minor League Baseball Research Articles

Facilitating the Transition out of Professional Baseball Following Release: A Self-Determination Theory Perspective

Approximately 90% of players in Minor League Baseball will be released at some point in their career. The purpose of this study was to qualitatively explore the role of individuals’ basic psychological needs during the release from professional baseball and throughout their subsequent transition to a new career. Semistructured interviews were conducted with 12 former Minor League Baseball players. Thematic analysis generated four themes: (a) The release resulted in immediate but temporary basic psychological need thwarting, (b) the “liberating experience” of the release allowed individuals to perceive autonomy in the transition out of affiliated baseball, (c) perceptions of competence served as the foundation for a positive transition to a new career, and (d) meaningful connections fostered individuals’ perception of relatedness in the transition out of affiliated baseball. The findings suggest that need fulfillment might act as a buffer between potential stressors in the transition process and athletes’ cognitive, emotional, and behavioral response.

Epidemiology, Treatment, and Performance-Based Outcomes in American Professional Baseball Players With Symptomatic Spondylolysis and Isthmic Spondylolisthesis

Background: Repetitive lumbar hyperextension and rotation during athletic activity affect the structural integrity of the lumbar spine. While many sports have been associated with an increased risk of developing a pars defect, few previous studies have systematically investigated spondylolysis and spondylolisthesis in professional baseball players. Purpose: To characterize the epidemiology and treatment of symptomatic lumbar spondylolysis and isthmic spondylolisthesis in American professional baseball players. We also sought to report the return-to-play (RTP) and performance-based outcomes associated with the diagnosis of a pars defect in this elite athlete population. Study Design: Descriptive epidemiology study. Methods: A retrospective cohort study was conducted among all Major and Minor League Baseball (MLB and MiLB, respectively) players who had low back pain and underwent lumbar spine imaging between 2011 and 2016. Players with radiological evidence of a pars defect (with or without listhesis) were included. Analyses were conducted to assess the association between player-specific characteristics and RTP time. Baseball performance metrics were also compared before and after the injury episode to determine whether there was an association between the diagnosis of a pars defect and diminished player performance. Results: During the study period of 6 MLB seasons, 272 professional baseball players had low back pain and underwent lumbar spine imaging. Overall, 75 of these athletes (27.6%) received a diagnosis of pars defect. All affected athletes except one (98.7%) successfully returned to professional baseball, with a median RTP time of 51 days. Players with spondylolisthesis returned to play faster than those with spondylolysis, MLB athletes returned faster than MiLB athletes, and position players returned faster than pitchers. Athletes with a diagnosed pars defect did not show a significant decline in performance after returning to competition after their injury episode. Conclusion: Lumbar pars defects were a common cause of low back pain in American professional baseball players. The vast majority of affected athletes were able to return to competition without demonstrating a significant decline in baseball performance.

Fracture Epidemiology in Professional Baseball From 2011 to 2017.

Background:Fractures are a significant cause of missed time in Major League Baseball (MLB) and Minor League Baseball (MiLB). MLB and the MLB Players Association recently instituted rule changes to limit collisions at home plate and second base.Purpose:To evaluate the epidemiologic characteristics of fractures in professional baseball and to assess the change in acute fracture incidence secondary to traumatic collisions at home plate and second base after the recently instituted rule changes.Study Design:Descriptive epidemiology study.Methods:The MLB Health and Injury Tracking System (HITS) database was used to access injury information on MLB and MiLB players to analyze fracture data from 2011 to 2017. Injuries were included if the primary diagnosis was classified as a fracture in the HITS system in its International Classification of Diseases, Ninth Revision, codes; injuries were excluded if they were not work related, if they occurred in the offseason, or if they were sustained by a nonplayer. The proportion of fractures occurring due to contact with the ground or another person in the relevant area of the field—home plate or second base—in the years before rule implementation was compared with the years after.Results:A total of 1798 fractures were identified: 342 among MLB players and 1456 among MiLB players. Mean time missed per fracture was 56.6 ± 48.4 days, with significantly less time missed in MLB (46.8 ± 47.7 days) compared with MiLB (59.0 ± 48.3 days) (P < .0001). A 1-way analysis of variance with post hoc Bonferroni correction demonstrated that starting pitchers missed significantly more time due to fractures per injury than all other position groups (P < .0001). Acute fractures due to contact with the ground or with another athlete were significantly decreased after rule implementation at home plate in 2014 (22 [3.0%] vs 14 [1.3%]; P = .015) and at second base in 2016 (90 [7.0%] vs 23 [4.5%]; P = .045).Conclusion:The recently instituted rule changes to reduce collisions between players at home plate and at second base are associated with reductions in the proportion of acute fractures in those areas on the field.

Gastrocnemius Injuries in Professional Baseball Players: An Epidemiological Study

Background: Gastrocnemius injuries are a common lower extremity injury in elite baseball players. There are no current epidemiological studies focused on gastrocnemius injuries in professional baseball players that provide information on the timing, distribution, and characteristics of such injuries. Hypothesis: Gastrocnemius injury in professional baseball players is a common injury that is influenced by factors such as age, player position, and time of season. Study Design: Descriptive epidemiological study. Methods: Based on Major League Baseball’s (MLB’s) Health and Injury Tracking System (HITS) database, gastrocnemius injuries that caused time out of play for MLB and Minor League Baseball (MiLB) players during the 2011-2016 seasons were identified. Player characteristics, including age, level of play, and position at time of injury, were collected. Injury-specific factors analyzed included date of injury, time of season, days missed, and activity leading to injury. Results: A total of 402 gastrocnemius injuries (n = 145, MLB; n = 257, MiLB) occurred during the 2011-2016 seasons. MLB players were significantly older at the time of injury (30.1 years, MLB; 23.9 years, MiLB; P < .001). Base running (36.1%) was the most common activity causing the injury, followed by fielding (23.6%), with 50.3% of base-running injuries sustained on the way to first base. In MLB players, gastrocnemius injuries were most common in infielders (48.3%), followed by pitchers (27.6%) and then outfielders (17.9%), while for MiLB players the injuries were more evenly distributed (33.5%, 28.8%, and 30.7%, respectively). The frequency of injuries in MLB players dropped off after the start of the regular season, whereas MiLB players had a consistent injury rate throughout the year. Conclusion: Gastrocnemius injuries are a common cause of lower extremity injury in professional baseball players, resulting in significant time out of play. Base running, particularly to first base, was the most common activity during injury. Outfielders had the fewest injuries; however, they required the longest time to recover. This study provides the first investigation to date with the HITS database to examine the characteristics and distribution of gastrocnemius injuries in professional baseball players, offering insight into risk factors, injury prevention, and recovery expectations.

Epidemiology of acromioclavicular joint injuries in professional baseball: analysis from the Major League Baseball Health and Injury Tracking System

Shoulder injuries account for a large portion of all recorded injuries in professional baseball. Much is known about other shoulder pathologies in the overhead athlete, but the incidence and impact of acromioclavicular (AC) joint injuries in this population are unknown. We examined the epidemiology of AC joint injuries in Major League Baseball (MLB) and Minor League Baseball (MiLB) players and determined the impact on time missed. The MLB Health and Injury Tracking System was used to compile records of all MLB and MiLB players from 2011 to 2017 with documented AC joint injuries. These injuries were classified as acute (sprain or separation) or chronic (AC joint arthritis or distal clavicular osteolysis), and associated data extracted included laterality, date of injury, player position, activity, mechanism of injury, length of return to play, and need for surgical intervention. A total of 312 AC joint injuries (183 in MiLB players and 129 in MLB players; range, 39-60 per year) were recorded: 201 acute (64.4%) and 111 chronic (35.6%). A total of 81% of acute and 59% of chronic injuries resulted in time missed, with a mean length of return to play of 21 days for both. Of the injuries in outfielders, 79.6% were acute (P < .0001), as were 66.3% of injuries in infielders (P = .004). Pitchers and catchers had more equal proportions of acute and chronic AC injuries (P > .05for all). Acute AC injuries occurred most often while fielding (n = 100, 84.7%), running (n = 25, 80.6%), and hitting (n = 19, 61.3%), whereas chronic injuries tended to be more common while pitching (n = 26, 68.4%). Of contact injuries, 82.5% were acute (P < .0001), whereas 59.0% of noncontact injuries were chronic (P = .047). MLB players showed consistently higher regular-season rates of both acute and chronic AC injuries than MiLB players (P < .0001 for each). Acute AC joint injuries are contact injuries occurring most commonly among infielders and outfielders while fielding that result in 3 weeks missed before return to play, whereas chronic AC joint injuries occur more commonly in pitchers and catchers from noncontact repetitive overhead activity. Knowledge of these data can better guide expectation management in this elite population to better elucidate the prevalence of 2 common injury patterns in the AC joint.

Effects of Employees’ Extra-Role Behaviors on Organizational Performance: An Assessment of Minor League Baseball Team Front Offices

The purpose of this study was to examine the effects of employees’ extra-role behaviors on desired organizational outcomes in sport. An assessment of innovative work behaviors and organizational citizenship behaviors of Minor League Baseball team front office employees was conducted as organizations planned for an upcoming season. An empirical model controlling for extraneous factors was developed and tested. Results revealed organizational citizenship behaviors of front office employees positively affected attendance during the season for Triple-A and Double-A level franchises. No significant effects between employees’ organizational citizenship and team attendance was seen in lower level teams. Employees’ innovative work behaviors were not significantly related to team attendance. The current study indicates that these sport organizations may not be benefitting from the behaviors it celebrates in its employees, namely the extra role behaviors. This study has demonstrated that context specific factors can substantially alter expected employee and organizational behaviors.

Ankle and Lower Leg Injuries in Professional Baseball Players

Background: Ankle and lower leg injuries are very common in sports, and numerous studies have discussed their diagnosis and management. Our study differs in that we report lower leg injuries in professional baseball players spanning the 2011-2016 seasons by utilizing a comprehensive injury surveillance system developed by Major League Baseball (MLB). Purpose: To determine the injury characteristics of ankle and lower leg injuries in professional baseball players during the 2011-2016 seasons by utilizing the MLB injury surveillance system. Study Design: Descriptive epidemiology study. Methods: Our study is a descriptive epidemiological evaluation through a retrospective review of injury data from the MLB Health and Injury Tracking System (HITS) since its implementation in 2010. We included any professional baseball player (MLB and Minor League Baseball [MiLB]) who was identified as having an ankle or lower leg injury between January 1, 2011, and February 28, 2017. Results: Over the study period, there were a total of 4756 injuries, of which 763 (16%) occurred in MLB players and 3993 (84%) occurred in MiLB players. The mean number of days missed for all players was 27.8 ± 141.4 days, with a median of 3 days. From 2011 through 2016, it was estimated that there were 414,912 athlete exposures (AEs) in MLB and 1,796,607 AEs in MiLB. Of the 4756 injuries recorded, 550 (12%) took place during the MLB regular season, and 3320 (70%) took place during the MiLB regular season. Injuries in MLB players, however, were 1.7 times more likely to require surgery (P < .001). Additionally, rates of injury to the lower leg were stratified by position, with infield players experiencing injuries at a 1.6 times greater rate than any other position (P < .001). Conclusion: In conclusion, this is the only epidemiological study to focus primarily on ankle and lower leg injuries in professional baseball players, utilizing an injury surveillance system developed by MLB.

On the Road With Minor League Baseball Externalities

Investigation of minor league demand is scant relative to major leagues, particularly at the game level. This presents not only a contextual gap in the research, but also a conceptual one related to demand externalities. Minor League Baseball differs from major professional leagues in that gate revenue sharing is not a fixture in league policy, and talent investment decisions are made by the parent club. Nonetheless, it may be the case that a host club benefits from characteristics of its opponent. Econometric examination of over 31,000 minor league games across multiple leagues and seasons finds proximity to an opponent’s major league parent team increases attendance. Although the authors find evidence of increased demand for a top prospect from the home club, the presence of visiting top prospects is not associated with changes in attendance, prompting the question as to whether effective marketing efforts in this regard would increase home club revenues.

Casey at the Bank: A Proposed Financial Instrument to Facilitate Risk-Hedging by Minor League Baseball Players

Casey at the Bank: A Proposed Financial Instrument to Facilitate Risk-Hedging by Minor League Baseball Players

Influencing Factors on Spectators' Revisit Intention In Minor League Baseball (MiLB): Spectators' Perceptions of Complaint Management Practices

This study investigates four influencing factors (i.e., facility quality, performance quality, interaction quality, and complaint management) on fans' satisfaction and perceived value, which further leads the intention to return. A total of 238 respondents of a Class A Short Season Minor League Baseball (MiLB) team participated in an online survey. Data were analyzed primarily with structural equation modeling (SEM) to investigate the relationship between study variables. The results indicated that spectators' satisfaction was influenced by interaction quality, performance quality, and complaint management while perceived value was predicted by facility quality and interaction quality. In predicting spectators' revisit intention, fans' perceived value was more critical in comparison to their perceived level of satisfaction.

Analysis of Non-Game Injuries in Major League Baseball

Background:Numerous studies have investigated injuries and treatments in the baseball athlete. The majority of these studies have focused on the throwing shoulder and elbow. However, more recent literature is reporting injuries to other regions in this cohort, including the knee, head, hip, and hamstring.Purpose/Hypothesis:The purpose of the current study was to determine the number and type of injuries in Major League Baseball (MLB) and Minor League Baseball (MiLB) players that do not occur during the actual game but are related to baseball participation. Our hypothesis was that there would be a substantial number of injuries that occurred in professional baseball players during non-game situations.Study Design:Descriptive epidemiological study.Methods:Deidentified, anonymous data were collected from the 2011 through 2016 seasons from the MLB Health and Injury Tracking System (HITS) medical record database. All injuries that were identified as a primary diagnosis and resulted in at least 1 day out of play from both MLB and MiLB were examined. Injuries were categorized as occurring during the game (“game” injuries) or not during the game. A “non-game” injury was defined as occurring at any time other than during the scheduled game from the first to last pitch.Results:There were 51,548 total injuries in MLB and MiLB players from 2011 to 2016, almost 40% of which were attributed to non–game-related injuries (n = 19,201; 37.2%). The remainder occurred during a game (n = 32,347; 62.8%). A significantly greater percentage of non-game injuries were season ending (10.8%) compared with the percentage of game-related season-ending injuries (8.4%) (P < .0001). Pitchers had significantly more non–game-related injuries than game-related injuries (P < .0001).Conclusion:A large number of injuries occur in professional baseball outside of actual games. MiLB players, specifically pitchers, are particularly at risk for these types of injuries. It is feasible that the overall injury rate in professional baseball players could be reduced by analyzing these injuries in more detail to develop prevention strategies.

Getting to First Base: Developmental Trajectories of Major League Baseball Players.

The road to professional baseball illustrates the complexity, variability and non-linearity of athlete development, as players may be drafted from various high school, 2 year, or 4 year programs and then placed into extensive minor league systems. The purpose of this study was to identify the different pathways to Major League Baseball (MLB) and explore their influence on career success. Performance and developmental data of 2,291 American-born MLB players who debuted between 1990 and 2010 were collected using baseball-reference.com. Three performance indicators, career games played (GP), age of debut, and wins above replacement (WAR; player’s total contributions in wins), were coupled with high school, post-secondary, and Minor League Baseball (MiLB) data. Analyses revealed 17 descriptively different pathways to MLB, which were grouped into three main streams based on the last institution attended before entrance into professional baseball. Overall, 63% of the athletes started their career directly after attending a 4 year higher education institution, 23% after high school, and 14% directly after attending a 2 year institution. Interestingly, 78% of the athletes did not sign or were not selected as high school draft picks. Position players drafted or signed from high school debuted in MLB younger (M = 23.99) and averaged significantly more MiLB GP (M = 909.13) than those drafted or signed from a 2 year (M = 25.67 and 834.41 GP) or 4 year institution (M = 25.95 and 752.33 GP). Pitchers signed or drafted from high school also debuted in MLB younger and played more MiLB games, as well as played in more MLB games than players from a 2 year or 4 year institution, F(8, 3,082) = 31.96, p ≤ 0.001. No significant differences of WAR were noted in position players or pitchers. Perhaps pitchers who are drafted from high school are afforded more opportunities to succeed, which may be indicative of sunk cost effects. This is conceivable as these players had the highest average GP but did not accrue a higher WAR. Future research may benefit from the consideration of post-secondary and/or high school statistics in combination with draft selection data, which may have important implications for improving talent identification accuracy.

Cost analysis of Tommy John surgery for Major League Baseball teams

The economic loss following ulnar collateral ligament reconstruction (UCLR) in Major League Baseball (MLB) pitchers has not been evaluated. The purpose of this study is to quantify the financial impact of UCLR on MLB teams. We hypothesize that MLB teams incur significant losses annually as a result of salaries paid to injured players following reconstruction. Public records were accessed to identify MLB pitchers from January 1, 2004, to December 31, 2014, who had undergone UCLR. Contract terms and time away from competition were used to approximate economic loss. Successful return was considered when a pitcher returned to play in at least 1 Minor League Baseball (MiLB) or MLB game. One hundred ninety-four MLB pitchers underwent UCLR from 2004 to 2014, missing on average 180.2 days of the MLB regular season. Cost of recovery (COR) amounted to $395 million, averaging $1.9 million per player. Starting pitchers accounted for the largest total COR at $239.6 million, whereas closers had the largest economic loss per player ($3.9 million/player). Only 77% of pitchers returned to MLB play. UCLR has a substantial economic impact on MLB teams. Starting pitchers represented a majority of team cost, but closers represented higher costs per pitcher.

Nonoperative Treatment of Elbow Ulnar Collateral Ligament Injuries With and Without Platelet-Rich Plasma in Professional Baseball Players: A Comparative and Matched Cohort Analysis

Background: Recent studies evaluating nonoperative treatment of elbow ulnar collateral ligament (UCL) injuries augmented with platelet-rich plasma (PRP) have shown promising results. To date, no comparative studies have been performed on professional baseball players who have undergone nonoperative treatment with or without PRP injections for UCL injuries. Hypothesis: Players who received PRP injections would have better outcomes than those who did not receive PRP. Study Design: Cohort study; Level of evidence, 3. Methods: The Major League Baseball (MLB) Health and Injury Tracking System identified 544 professional baseball players who were treated nonoperatively for elbow UCL injuries between 2011 and 2015. Of these, 133 received PRP injections (PRP group) before starting their nonoperative treatment program, and 411 did not (no-PRP group). Player outcomes and a Kaplan-Meier survival analysis were compared between groups. In addition, to reduce selection bias, a 1:1 matched comparison of the PRP group versus the no-PRP group was performed. Players were matched by age, position, throwing side, and league status: major (MLB) and minor (Minor League Baseball [MiLB]). A single radiologist with extensive experience in magnetic resonance imaging (MRI) interpretation of elbow injuries in elite athletes analyzed 243 MRI scans for which images were accessible for tear location and grade interpretation. Results: Nonoperative treatment of UCL injuries resulted in an overall 54% rate of return to play (RTP). Players who received PRP had a significantly longer delay in return to throwing (P < .001) and RTP (P = .012). The matched cohort analysis showed that MLB and MiLB pitchers in the no-PRP group had a significantly faster return to throwing (P < .05) and the MiLB pitchers in the no-PRP group had a significantly faster RTP (P = .045). The survival analysis did not reveal significant differences between groups over time. The use of PRP, MRI grade, and tear location were not statistically significant predictors for RTP or progression to surgery. Conclusion: In this retrospective matched comparison of MLB and MiLB pitchers and position players treated nonoperatively for a UCL tear, PRP did not improve RTP outcomes or ligament survivorship, although there was variability with respect to PRP preparations, injection protocols, time from injury to injection, and rehabilitation programs. MRI grade and tear location also did not significantly affect RTP outcomes or progression to surgery.

Prevalence of Medial Ulnar Collateral Ligament Surgery in 6135 Current Professional Baseball Players: A 2018 Update.

Background:As the incidence of ulnar collateral ligament (UCL) surgery continues to rise rapidly, an update on the current prevalence and demographics in professional baseball players is warranted.Hypothesis:The prevalence of UCL reconstruction in Major League Baseball (MLB) and Minor League Baseball (MiLB) players will be higher than that previously reported, and the increase in prevalence will be most notable in MiLB pitchers.Study Design:Cross-sectional study; Level of evidence, 3.Methods:During the 2018 baseball season, an online questionnaire regarding a history of UCL surgery was distributed to the certified athletic trainers of all 30 MLB organizations. These trainers then administered the survey to all players within their organizations, including MLB, MiLB (AAA, AA, High A, Low A, High Rookie, Low Rookie), and Dominican Summer League (DSL) players. Demographics were compared between MLB, MiLB, and DSL players. Results of this 2018 survey were compared with previously published data from the 2012 season to assess the change over time.Results:There were 6135 professional baseball players who completed the survey (66% response rate). The prevalence of UCL reconstruction in all MLB and MiLB players was 13% (637/4928), while the prevalence in DSL players was 2% (20/1207) (P < .001). The prevalence in all MLB and MiLB players (13%) and pitchers (20%) both increased significantly from 2012 (P < .001). MLB pitchers reported a higher prevalence of UCL reconstruction than did MiLB pitchers (26% vs 19%, respectively; P < .001). In 2018, the prevalence of UCL reconstruction has increased significantly in MiLB pitchers (19% vs 15%, respectively; P < .001) and pitchers aged 21 to 30 years (22% vs 17%, respectively; P < .001) compared with 2012. Additionally, United States–born pitchers were more likely to have undergone UCL reconstruction compared with Latin America–born pitchers (23% vs 13%, respectively; P < .001).Conclusion:The prevalence of UCL reconstruction has increased significantly in professional baseball players over the past 6 years from 10% to 13%. Ultimately, the prevalence of UCL reconstruction has increased most significantly since 2012 in MiLB pitchers, pitchers aged 21 to 30 years, and pitchers born in the United States.

Fun, Failure, and Fulfillment: A Case-Study Approach to Informal Athlete Leadership in Minor League Baseball

The purpose of this study was to crystalize a single case of informal athlete leadership in Minor League Baseball (MiLB) during the 2015 season. Teammates and coaches of a Class A MiLB team voted for the highlighted participant as the best athlete leader on the team. The first author conducted 8 individual semistructured interviews with the participant, 2 coaches, and 5 teammates. Using interpretative phenomenological analysis and open-ended prompts based on leadership and athlete literature, the first author learned about the highlighted participant’s emergence as a leader on a team without formal leadership titles. Findings revealed 4 main themes: navigating personal on-the-field failure, fulfilling others’ expectations, helping teammates manage emotions, and fostering a fun working environment. Findings also indicated 1 foundational theme, having a philosophy, that grounded the 4 main themes. Implications for athlete leadership development and future directions for athlete leadership research are discussed.

Do Professional Baseball Players With a Higher Valgus Carrying Angle Have an Increased Risk of Shoulder and Elbow Injuries?

Background:There are many risk factors for shoulder and elbow injuries in professional baseball pitchers. The elbow carrying angle has not been studied as a potential risk factor.Purpose/Hypothesis:The aim of this study was to determine whether elbow carrying angle is a risk factor for shoulder or elbow injuries in professional baseball pitchers. We hypothesized that pitchers with a higher elbow carrying angle would be less likely to sustain an injury during the season than pitchers with a lower elbow carrying angle.Study Design:Cohort study; Level of evidence, 2.Methods:All professional pitchers for a single baseball club during the 2018 season had the carrying angle of both elbows measured at spring training by a single examiner. The pitchers were followed prospectively throughout the season. Shoulder and elbow injuries were recorded prospectively.Results:A total of 52 pitchers (21 [40%] Major League Baseball and 31 [60%] Minor League Baseball) were included. During the season, 23 (44%) pitchers became injured. The mean carrying angle in the throwing arm was 12.5° ± 4.2° versus 9.9° ± 2.8° in the nonthrowing arm (P < .001). Comparing the injured and noninjured groups, there were no differences in level of play (P = .870), throwing hand dominance (P = .683), batting hand dominance (P = .554), throwing-side carrying angle (P = .373), nonthrowing-side carrying angle (P = .773), or side-to-side difference in carrying angle (P = .481).Conclusion:The elbow carrying angle was not associated with an injury risk during a single season in professional baseball pitchers.

Epidemiology and Impact of Hand and Wrist Injuries in Major and Minor League Baseball.

Background: Professional baseball players are at risk of acute and chronic injuries to their upper extremities. Methods: Major League Baseball's Health and Injury Tracking System, a prospective injury surveillance system, was used to identify and characterize all hand and wrist injuries sustained by all Major League Baseball (MLB) and Minor League Baseball (MiLB) players during the pre-, regular, and postseason throughout 2011-2016. Injuries were included if they resulted in at least 1 day out of play and were sustained during standard baseball activities. Days missed were defined as the time between injury and the first time in which a player was cleared to return to play. Results: During the study period, there were 4478 hand and 1748 wrist injuries throughout MLB and MiLB, which resulted in a total of 105 246 days out of play. This was equivalent to the length of 575 individual MLB player seasons, and the mean days missed per injury was 17 days. Most injuries were traumatic in nature, with 43% (n = 2672) of players injured after being hit by a baseball that mainly occurred during batting (n = 2521; 40%). Injuries that most frequently required surgical intervention were hook of hamate fractures (72%) and scaphoid fractures (60%). Conclusions: Understanding the epidemiology and impact of hand and wrist injuries in MLB and MiLB players may lead to improved management of these injuries and reduce time away from play. Most importantly, preventive measures and/or enhanced protective gear may be developed to minimize these types of injuries in MLB and MiLB.

Association Between a Rule Change to Reduce Home Plate Collisions and Mild Traumatic Brain Injury and Other Injuries in Professional Baseball Players

Background: Improved player safety is an important goal of professional baseball. Prevention of mild traumatic brain injury (concussion) is an area of emphasis because of the potential for long-term as well as short-term sequelae. Hypothesis: A rule change can lower the incidence of concussions and other injuries in professional baseball. Study Design: Cohort study; Level of evidence, 3. Methods: This study included a retrospective review of data entered concurrently into professional baseball’s electronic medical record system. All minor and major league teams are required to use this system. All injuries are captured by creation of a new record in the system at the time of the injury. All active minor and major league players from 2011 to 2017 were included. The 30 major league clubs have 1200 roster players and play 162 games per season. The approximately 200 minor league clubs have about 7500 active players and play 56 to 144 games annually that combine for approximately 330,000 athlete-exposures per season. Before the 2014 season, Major League Baseball, in conjunction with its players association, instituted a rule limiting home plate collisions between base runners and catchers that applied to both Major League Baseball and Minor League Baseball. All concussions and other injuries at home plate from 2011 to 2017 were analyzed by mechanism and player position. Results: From 2011 to 2013, an annual mean of 100 injuries occurred from home plate collisions in the minor and major leagues, resulting in a mean loss of 2148 days annually. After the rule change, there was a mean 55 home plate collision injuries with 936 days lost per season (P < .0001 for injuries and days lost). A mean 11 concussions attributed to these collisions occurred annually in the minor and major leagues before the rule change, as compared with 2.3 per year after (P = .0029). There were no major league concussions from these collisions after the rule change. The mean annual number of days missed because of concussions at home plate dropped from 276 before 2014 to 36 per year after 2014 (P = .0001). Conclusion: This rule change was associated with significant reductions in the numbers of concussions and other injuries caused by collisions at home plate as well as significant decreases in time lost from play.

Hamstring Injury Trends in Major and Minor League Baseball: Epidemiological Findings From the Major League Baseball Health and Injury Tracking System.

Background:Hamstring strains are the most common injury for professional baseball players and can result in significant time on the disabled list. To date, no study has reported the current trends in hamstring strains in professional baseball.Hypothesis:Professional baseball players would have an increased incidence of hamstring strains from 2011 through 2016.Study Design:Descriptive epidemiology study.Methods:Injury data were prospectively collected from 2011 through 2016 for every Major League Baseball (MLB) and Minor League Baseball (MiLB) team and was recorded in the MLB Health and Injury Tracking System. Data collected for this study included date of injury, activity during injury, time lost, primary injury or reinjury status, and imaging findings as well as player demographic information related to level of play, age, and position for all hamstring injury events. Injury rates were reported as hamstring injuries per number of games.Results:From 2011 to 2016, there were 2633 hamstring strains in professional baseball players. The rate of hamstring strains increased in MLB from a low of 1 injury every 39 games in 2011 to a high of 1 injury every 30 games in 2016. In MiLB, there were 2192 hamstring strains, with 1 injury every 35 games in 2011 compared with 1 injury every 30 games in 2016. The majority of injuries occurred in the infielder positions (37.5%) and resulted from base running (>50%), most commonly from home to first base. The most common hamstring injury was a grade 2 injury to the distal biceps femoris. The mean time missed after a hamstring injury was 14.5 days. Grade 3 and grade 2 hamstring strains resulted in significantly more days missed compared with grade 1 injuries (P = .005 and P = .002, respectively). The rate of recurrent hamstring injuries was 16.3% for MLB and 14.2% for MiLB. Recurrent hamstring injuries resulted in more time lost than primary injuries (mean, 16.4 vs 14.5 days, respectively; P = .02). A total of 42 injuries were treated with platelet-rich plasma, and 19 were treated with surgery. The number of injuries treated with platelet-rich plasma increased in successive years.Conclusion:The rate of hamstring strains in professional baseball players has increased over the past 6 years and has resulted in a significant loss of playing time. Study results indicated that these injuries are affected by injury characteristics, position played, running to first base, seasonal timing, and history of hamstring injuries.