Abstract
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.
The gastrocnemius muscle plays a major role in nearly every baseball-related movement, as it is heavily utilized for quick leg movements, running, jumping, and, to a lesser degree, standing and walking.14,19 Specifically, the gastrocnemius muscle functions to plantarflex the foot at the ankle joint and to flex the knee, both of which are vital movements to athletes performing at the highest level.14,23 Gastrocnemius strain is a common sports injury that results in time out of play in multiple sports, including professional baseball. 23 Baseball players are especially prone to gastrocnemius injuries, given their explosive push-off acceleration and deceleration during running.19,23,24
Previous epidemiological studies of baseball injuries have shown that 5% of all injuries sustained by professional baseball players were due to injuries to the lower leg.5,7 Calf injuries, including gastrocnemius strains, follow only hamstring, hip adductor, quadriceps, and ankle injuries in frequency for lower extremity injuries and accounted for 70 injuries per Major League Baseball (MLB) season from 2011 to 2016.3,16 Specifically, gastrocnemius muscle strains were in the top 20 of all injuries sustained by professional baseball players, resulting in a mean 11.6 days missed per injury. 3 The mechanism of injury for gastrocnemius muscle strains are more often the result of acute, noncontact injuries with no predilection for pitchers, fielders, or batters. 3
The MLB Health and Injury Tracking System (HITS) was implemented for the beginning of the 2010 season and allows for a more robust analysis of common injuries than previous methods of data management.6,7,17,18 Injury data are entered by club athletic trainers and medical professionals caring for MLB and Minor League Baseball (MiLB) teams. Although gastrocnemius injuries are a major cause of morbidity in professional athletes, there have been no studies focusing on evaluating the epidemiological characteristics of gastrocnemius injuries with the HITS.3,23 Previous studies have evaluated all types of injuries, without a specific subset analysis of gastrocnemius injuries.3,15 Over the past several years, the HITS has allowed for the investigation of epidemiological characteristics of different injuries commonly seen in professional baseball players, including traumatic brain injuries, 13 elbow injuries, 4 hip and groin injuries, 5 knee injuries, 8 hamstring injuries, 1 and abdominal injuries, 2 among others. These studies have proven to be extremely valuable in understanding the true nature of these injuries, providing athletic trainers, physical therapists, and team physicians better data to help guide treatment decisions and offer improved recovery expectations for players and clubs. These data also provide information regarding positions or activities that result in greater risk for certain injuries, which may help focus future injury prevention efforts. In addition, these studies have the potential to be useful for nonmedical professionals, such as front office and on-field personnel, who may make decisions on roster management for players with these injuries.
The purpose of this work was to utilize the HITS database to provide an updated report on the epidemiology and effect of gastrocnemius injuries in MLB and MiLB. Specifically, we sought to (1) better understand the true incidence and rate of gastrocnemius injuries in this elite athletic population, (2) determine the effect of these injuries based on time out of play, and (3) use these data to identify specific injury patterns and at-risk athletes to lay a foundation for potential injury prevention programs in the future. We hypothesized that gastrocnemius injuries in professional baseball players are influenced by factors such as age, player position, and time of season. Despite focused injury prevention in recent years, these injuries are likely to continue to represent a significant cause for time out of play among professional baseball players, warranting further investigation.
Methods
Gastrocnemius injury data were collected for all MLB and MiLB players for the 2011-2016 seasons. MLB consists of approximately 750 active players on 30 teams throughout the United States and Canada. The teams are divided into 2 leagues, the American League and National League, with each team playing 162 games scheduled over a 180- to 183-day regular season. MiLB consists of approximately 6500 active players on >200 teams spread across North America, South America, and the Caribbean. There are roughly 1000 inactive players in the minor leagues at any given time for several reasons: some are on the injured list (formerly, the disabled list), and others are on the restricted or inactive lists. MiLB also sees an increase in players in late June and July, when amateur players are signed. Each minor league team is affiliated with a specific major league parent ball club, which contracts all players on its minor league teams. Minor league teams are divided into different leagues (ie, AAA, AA, A, Rookie Ball) based on skill level and geographic location. The major league and a majority of the minor league players report for spring training in February, with regular season play beginning in late March or early April and ending in September. Some lower-level minor league seasons are shorter, with play beginning in mid-June and running until early September.
Data Acquisition
All injuries were recorded in the MLB HITS between 2011 and 2016; the data extracted from the HITS for this study included only injuries that resulted in lost game time for a player and occurred during spring training, regular season, or postseason play. Injuries and player symptoms were recorded in the database by each team’s certified athletic trainer. Offseason injuries were not included in the analysis. Injury events that were classified as “season ending” were not included in the analysis of days missed, to account for potential cases in which a player may not have been cleared to play until the beginning of the following season, upon arrival at spring training. Therefore, calculation of days missed may not accurately reflect time away from play in the same way that it does for non-season-ending injuries. Season-ending injury events were excluded only when days missed were summarized, but they were included for all other analyses, such as incidence, age, position, percentage requiring surgery, and reinjury. This is consistent with the reporting methods of other published epidemiological studies evaluating concussion, knee, hip, hamstring, abdominal, and elbow injuries in professional baseball players.1,2,4,5,8,13
Defining Gastrocnemius Injury and Related Characteristics
For the purpose of data extraction, a gastrocnemius injury was defined as follows: an event with the body region variable identified as “Lower Leg / Achilles Tendon” with a primary injury diagnosis of gastrocnemius sprain, strain or tear, which was classified as work related injury and did not occur in the off season. All gastrocnemius injuries, acute and chronic, resulting in lost game time were extracted from the HITS for MLB and MiLB players during the 2011-2016 seasons. For each injury, a multitude of variables were analyzed, including date of injury, time of season, days missed, activity leading to injury, location on the field, mechanism, body side, surgical and nonsurgical treatment, and recurrence rates. Player-specific characteristics included age, level of play, position at the time of injury (called “event position”), batting-side dominance, and throwing-side dominance. The only exception was the event position variable, which was added to the HITS during the 2012 season; therefore, this was designated as “not classified” for the 2011 season. All data were deidentified and void of player name.
Data Analysis
All epidemiological data are reported with descriptive statistics (mean, SD, median, range, frequency, and percentage) where indicated. When pairwise comparisons were made between means of continuous variables, such as number of days missed, a Student t test was utilized to assess for significant differences for all normally distributed values, and mean differences with 95% CIs are provided. When means of ≥3 groups of continuous variables were compared, analysis of variance was performed. For categorical data (eg, pitcher vs hitter, major vs minor league), proportions were compared with Fisher exact tests to calculate a 2-tailed P value. Differences in the number of observed and expected injuries among groups were compared by chi-square analysis. To determine the significance of trends over time, a best-fit line was generated to illustrate the change over the years. These lines are reported with their corresponding R 2 values to assess the trend for statistical significance; the slope of this best-fit line was compared against a line with a slope of zero (no change over time) per regression analysis. For all statistical comparisons, the threshold for alpha was set to P < .05.
Analysis also included calculation of gastrocnemius injury rates. To estimate athlete exposure, the mean number of players per team per game was based on analysis of regular season game participation via box scores, consistent with previous epidemiological baseball studies.1,2,4,16,18 This mean number over a season, multiplied by the number of team games at each level of professional baseball, was used as an estimate of athlete-exposures (AEs) to provide rates comparable with those of other injury surveillance systems. Injury rates were reported as injuries per 1000 AEs for those gastrocnemius injuries that occurred during the regular season.
Initial statistical analysis was conducted within the R Statistical Computing Environment, 22 with additional analysis completed with Stata (Version 15, StataCorp).
Results
There were 419 gastrocnemius injuries sustained between 2011 and 2016 in MLB and MiLB players: 147 spasms (35.1%), 269 strains (64.2%), and 3 tears (0.7%). The 3 gastrocnemius tears were excluded for further analysis. MLB players were less likely to have season-ending injuries as compared with MiLB players (n = 1 [0.7%] vs n = 13 [4.8%], respectively) but were more likely to reinjure their gastrocnemius during the study period (2.8% vs 0.8%). None of the players required surgical repair for their injury, and there was no significant difference in acuity of injury or body side injured.
Of the 416 injuries that met inclusion criteria, 146 (36.1%) occurred in MLB players and 270 (63.9%) in MiLB players (Table 1). The mean age of MLB players at the time of injury was 30.1 years (range, 19.4-43.3 years) as compared with 23.9 years (range, 16.8-36.5 years; P < .001) in MiLB players. MLB players missed a mean 12.7 days because of gastrocnemius injury, for a total of 1837 days over the study period. MiLB players had slightly fewer days missed, 10.9 days per injury on average, with a total of 2810 days missed over the course of the study (P = .377).
Characteristics of Professional Baseball Gastrocnemius Injuries, 2011-2016 a
MiLB, Minor League Baseball; MLB, Major League Baseball.
Gastrocnemius injuries trended downward per year from the 2011-2016 seasons, as shown in Table 2 , but this trend was not significant among years (P = .696). The injury rate per 1000 AEs for MiLB was 0.121, as compared with the MLB rate of 0.196. The overall combined injury rates per 1000 AEs for each year were calculated and did not show significance per the chi-square test (P = .651). Mean days missed attributed to injury during the study period was 11.6 days per injury, ranging from a low of 7.8 days in 2016 up to 15.2 days in 2015, with no general trend up or down. The mean number of days missed did not differ significantly among years (P = .3915) or between leagues, except for 2014 (P = .02). The mean number of days missed did not differ among activities at the time of injury (P = .58).
Comparison of Gastrocnemius Injuries by Season, 2011-2016 a
DM, days missed; MiLB, Minor League Baseball; MLB, Major League Baseball.
Table 3 displays the distribution of gastrocnemius injuries by activity at the time of injury. For MLB and MiLB players, injuries occurred most often during base running (36.1% combined), followed by fielding activities (23.6% combined) and conditioning (13.2% combined), as shown in Figure 1. By total days missed, running was the highest (1564 days), followed by fielding (984 days), conditioning (701 days), pitching (541 days), batting (223 days), weight training (106 days), and throwing (28 days). MLB players displayed a small increase in injuries during conditioning and fewer injuries while pitching, but no significant difference was found between activity at the time of injury and level of play (P = .261). In comparing the mean number of injuries per season by activity, running was the highest at 24.2 injuries per year, followed by fielding (15.8/y), conditioning (8.8/y), pitching (7.5/y), batting (3.3/y), and throwing (1.3/y).
Frequency of Gastrocnemius Injuries by Activity, 2011-2016 a
DM, days missed; MiLB, Minor League Baseball; MLB, Major League Baseball.
Frequency of gastrocnemius injuries by activity at time of injury, 2011-2016.
Table 4 demonstrates that approximately two-thirds of base-running gastrocnemius injuries occurred while running (77.2% combined) versus sliding or other base path activities (Figure 2). No significant differences existed in type of running activity or location between MLB and MiLB (P = .218 and .372, respectively). Most base-running injuries occurred at first base (50.3% combined), with the percentage decreasing as the players progress around the diamond. The percentage of injuries occurring while base running to home plate was 3.1 times higher in MiLB players as compared with MLB players (11.8% vs 3.9%; P = .136). MiLB players were 5.4 times more likely than major league players to injure their gastrocnemius while sliding (9.7% vs 1.9%; P = .096).
Frequency of Gastrocnemius Injuries While Base Running, 2011-2016 a
DM, days missed; MiLB, Minor League Baseball; MLB, Major League Baseball.
Frequency of gastrocnemius injuries while base running by location at time of injury.
As shown in Figure 3, catchers (6.2%) and designated hitters (0.5%) made up the smallest percentages of gastrocnemius injuries by position, with no significant difference between levels of play in catchers (P = .520). The percentage of gastrocnemius injuries was significantly higher in MLB players than MiLB players for infield (48.3% vs 33.5%; P = .004) and first base (15.9% vs 7.0%; P = .006) but lower for outfield (17.9% vs 30.7%; P = .004) (Table 5). No other significant differences were found between position and level of play. Overall, center field (7.2%) was the most common outfield position to sustain a gastrocnemius injury for both leagues as compared with right field (3.5%) and left field (3.0%). For infielders at both levels of play, shortstop was the most common position to sustain a gastrocnemius injury (12.2%), followed by first base (10.2%), third base (7.5%), and second base (6.0%). In MLB, relief pitchers represented a slightly higher percentage of the injuries (11.7%, starter; 12.9%, relief), while the opposite was true in MiLB (16.7%, starter; 12.1%, relief).
Frequency of gastrocnemius injuries based on player position, 2011-2016. MiLB, Minor League Baseball; MLB, Major League Baseball.
Frequency of Gastrocnemius Injury and Days Missed by Player Position, 2011-2016 a
Values are presented as No. (%). DM, days missed; MiLB, Minor League Baseball; MLB, Major League Baseball.
Table 5 also displays the total and mean days missed caused by gastrocnemius injuries. No significant differences were found between position and mean days missed overall (P = .311). On average, center fielders took the most time to return to play (19.7 days), while catchers missed the least amount of playing time (3.2 days). No significant differences were found for mean days missed among positions by level of play (P > .05).
In general, gastrocnemius injuries were most frequent during spring training and then decreased as the season progressed (Table 6). Infielders were the group most represented, during the preseason (39.5% of total) and the regular season (38.7% of total), matched only by pitchers in the postseason. Pitchers and infielders represented 67.5% of all injuries across periods. Outfielders, meanwhile, consistently demonstrated the lowest proportion of injuries throughout the year, aside from May, during which they just surpassed infielders (40.4% outfielders vs 36.2% infielders). Outfielders showed the most consistent gradual decline in injuries through the season, while injuries in infielders were evenly distributed for most of the regular season (Figure 4). Pitchers demonstrated a strong decline at the beginning of the season but then had a small increase in injuries around the middle of summer before continuing to decline. Based on the distribution of gastrocnemius injuries by league, the number of injuries was similar during the pre- and postseason. However, in MLB, gastrocnemius injuries dropped off after the preseason and then remained steady for the rest of the regular season. In MiLB, the number of injuries stayed fairly constant throughout the season, dropping only in September as the season concluded. A greater number of overall injuries in MiLB would be expected given the increased number of players. Minor league seasons are different in duration as compared with the MLB season, but we would also have expected there to be a similar trend of increased injuries at the start of the season that decreases over time; it is unclear why this trend was not observed.
Frequency of Gastrocnemius Injury by Position Over Time, 2011-2016
No. of injuries.
Percentage by month.
Percentage by position.
Distribution of gastrocnemius injuries by month based on player position (top) and level (bottom), 2011-2016.
Players at both levels of play showed a significant increase in days missed for injuries sustained in April, at the beginning of the regular season. MLB players also showed a smaller peak in the month of July; this may be due to the all-star break in mid-July, which may have allowed for additional recovery days before return to play. There was an overall trend toward decreasing days missed as the season progressed for all players. There was a slight increase in season-ending injuries toward the end of the season, with 16.7% of the injuries in September being season ending, while between February and July, <4% of injuries were season ending.
Discussion
Previous epidemiology studies of professional baseball athletes have highlighted gastrocnemius injuries as one of the leading causes of time out of play. However, there have been no studies focusing on gastrocnemius injury trends and characteristics seen in professional baseball players with the HITS database. The purpose of our study was to utilize the HITS database to better understand the current incidence of gastrocnemius injuries, their true effect on time out of play, and specific injury characteristics that can be used to determine which players are most at risk for these injuries. Our hypothesis was confirmed: gastrocnemius injury was a common lower extremity injury that was influenced by factors such as age, player position, activity, time of season, and level of play. Major league players had a higher rate of gastrocnemius injury than minor league players (MLB injury rate, 0.196 per 1000 AEs; MiLB, 0.121); however, there was a greater number of injuries in MiLB, given the higher number of players and overall AEs. The higher rate of injury at the MLB level may be due to the older mean age of players or increase in pressure to perform at that level. The data have shown that gastrocnemius injuries are responsible for an annual mean of >750 days missed (the equivalent of >4 full-length MLB seasons) each year in all of professional baseball. The most common injury mechanism for MLB and MiLB players was base running, particularly while running to first base. In MLB, infielders represented a greater percentage of the gastrocnemius injuries than outfielders, whereas MiLB had a larger percentage of gastrocnemius injuries in outfielders than infielders.
Camp and colleagues’ 2018 summary 3 of professional baseball injuries provides a broad analysis on an array of injuries over the same period. In the supplemental data, their analysis of gastrocnemius injuries in baseball players shows similar trends to those found in this article with slightly different numbers, likely because of the different exclusion criteria during analysis. Our study offers a more complete analysis of gastrocnemius injuries in MLB and MiLB players, examining how position, level, time of the year, and other factors affect the rate of injury and recovery time. This information can be used to provide more accurate estimations of return to play, as well as to focus injury prevention efforts to peak months.
When injury trends in baseball injuries are assessed by year, it is important to adjust for exposure. In baseball research, this has historically been accomplished by calculating AEs and using these values to calculate injury rates per 1000 AEs. We compared our calculated injury rates per 1000 AEs with previous published research, specifically to the US National Collegiate Athletic Association (NCAA) Injury Surveillance System baseball game time-loss injury data published by Dick et al 9 in 2007 using similar injury and exposure definitions. We found that the combined MLB and MiLB game-related time-loss injury rates over the 2011-2016 seasons were similar to previously reported injury rates in NCAA athletes (0.13 vs 0.15).
For the major and minor leagues, base running was the top activity associated with gastrocnemius injuries and was associated with over one-third of overall injuries. The majority of the injuries that occurred during base running occurred while running to first base. The primary reason for this may simply be the increased number of trips to first base as compared with subsequent bases, providing greater opportunity for injury, similar to what is seen with hamstring injuries. 1 Additionally, base-running techniques differ among bases and may contribute as well. The acceleration from a rotating, stationary swinging action transitioning into sprinting to first base (and usually with no planned deceleration while approaching first base itself) is the most complex and frequent acceleration-related baseball activity relative to running to the other bases on the field or fielding, pitching, or catching. 12 More research is necessary to fully appreciate the biomechanical characteristics of this complex baseball-related activity. Investigations into whether these injuries have a higher likelihood of occurring while running out of the batter’s box from the right or left side could prove to be valuable in developing injury prevention programs.
Gastrocnemius injuries have been shown to be a limiting injury in professional baseball players, with previous studies reporting them to be a “lingering injury” that results in among the highest number of days missed for non-season-ending injuries. 3 In our study, gastrocnemius injuries caused MLB players to miss a mean 12.7 days, while MiLB players missed a mean 10.9 days. When these results are compared with other professional sports, specifically professional football and soccer, the number of days missed from game time is lower. In 2017, Werner et al 23 reported 17.4 ± 14.6 days missed (mean ± SD) because of gastrocnemius injuries among players on a single professional team competing in the National Football League from 2003 to 2015. In 2011, Ekstrand et al 11 reported 14.7 ± 14.4 days of absence in professional soccer players competing in 24 clubs in the Union of European Football Association, 15 teams in the Swedish First League, and an additional 15 European teams who had calf injuries from 2001 to 2009. In terms of mean days missed by position, MLB outfielders average 13 days, which is similar to the findings for professional soccer and football, whereas MLB infielders average 11 days and catchers only 3.3 days. This difference between infielders and outfielders may be due to the increased running demands in the outfield positions. Soccer and football (depending on position) also have significant running demands, with previously published studies reporting mean running distances of almost 6000 m in a soccer match. 21 Additionally, there may be some variation on the degree of gastrocnemius injury that players sustain among position or sports. The severity of the strain may influence the amount of time needed to return to play.
There is an overall trend toward decreasing days missed as the season progresses for all players, with a significantly greater number of days missed at the start of the season and around the all-star break in July. The early peak may be due to decreased pressure to return at the start of the season, or there may be more severe injuries early on as players return to a higher activity level. The exclusion of season-ending injuries may decrease the mean days missed later in the season, given the lower number of potential recovery days before the season ends. Players with longer recovery times may not have sufficient days left in the season to return to play.
Prompt diagnosis and early appropriate treatment are important for minimizing the degree of disability and resulting recovery duration. Treatment of gastrocnemius injuries is centered on reducing pain and hemorrhage and preventing complications such as muscle contracture, with surgery reserved for chronic and severe grade III injuries. In the acute phase (3-5 days), rest, ice, compression, and elevation are the primary treatment modalities.10,20 In this phase, heat, massage, and nonsteroidal anti-inflammatory drugs are generally avoided, owing to the risk of increased bleeding within the tissue. 20 Once past the acute phase, gentle stretching is important to prevent contracture and help elongate the intermuscular scar. Around 10 days, progressive strengthening, dynamic training exercises, and physical therapy modalities are then used, advancing activities as tolerated in a pain-free progression. Gradual progression of activities to preinjury baseline without early return to play is important, as early return before full recovery can prolong recovery or result in reinjury to the gastrocnemius. 10
To our knowledge, this is the most extensive review of gastrocnemius injuries in professional baseball; however, this study does have several limitations. We used the MLB HITS database, which is a robust tracking system that has recorded injury information on every MLB and MiLB player since the 2010 season, making it the most comprehensive database of its kind in professional sports. 17 Although the HITS database tracks the injury characteristics of professional baseball players systematically, it is not without some limitations. As with all databases, it is reliant on the accuracy and quality of the data entered. Although the HITS database was developed to help certified athletic trainers (ATCs), team physicians, physical therapists, and other medical staff input information in an easily reproducible and reliable format, there is always the possibility of inconsistent data entry, as well as the inevitable variability that exists among the numerous physicians and ATCs subjectively inputting their players’ injury characteristics. Additionally, our study is limited by its narrow scope of treatment information available. We were able to discern only whether the gastrocnemius injury sustained by a player required surgery or not. Treatment strategies other than surgery (rest, oral medications, bracing, therapy programs, etc) are not available for statistical analysis. In addition, these data reflect gastrocnemius injury trends and characteristics just in professional baseball athletes and may not be as applicable to other professional sports or amateur athletes. The HITS database tracks the number of days missed for each injury, which is indicative of injury severity, but there is no other quantifying factor within the database to easily determine the severity of each gastrocnemius injury.
Conclusion
Gastrocnemius injuries in professional baseball players were a significant cause of lower extremity injuries over the 2011-2016 seasons, resulting in 4647 missed days. Base running, particularly to first base, was the most common activity during injury, possibly because of the explosive sprinting movement and increased exposure while running to first base. Conditioning and weight training accounted for 18% of MLB gastrocnemius injuries and were found to result in the greatest mean days missed of all activities at the time of injury. MLB players had significantly more injuries among infielders than did MiLB players. The greatest number of injuries occurred at the transition between spring training and the regular season for MLB players, with the number of injuries significantly decreasing in the first few months of play. In MiLB players, the distribution of injuries was consistent throughout the year. Injuries occurring at the start of the season or around the all-star break in July had a significant increase in days; otherwise, there was a gradual decrease in days missed because of gastrocnemius injuries as the season progressed. The exclusion of season-ending injuries may have altered the mean days missed later in the season as the maximum number of possible days missed was decreased. 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.
Footnotes
Submitted December 26, 2019; accepted May 5, 2020.
One or more of the authors has declared the following potential conflict of interest or source of funding: K.H. has received education support from Smith & Nephew, Liberty Surgical, and Pinnacle Inc. S.B.C. has received consulting fees and hospitality payments from Zimmer Biomet. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.