Oblique Injuries in MLB

by Gene Coleman and Jose Vazquez

In 2011, there were 50 oblique injuries among MLB players and these players spent a total of 1,604 days on the DL. The average stay was 35 days for pitchers and 28 days for position players. The total cost of these 50 injuries (salaries paid to injured players plus salaries paid to players who replaced them) was more than $22 million.

Thirty percent of the injuries (N = 15) occurred to pitchers and 70% (N = 35) occurred to position players. Most of the injuries (80%) were on the non-dominant side (left side for right handed pitchers and batters and right side for left handed pitchers and batters). Interestingly, most of the injuries occurred during the months of March and April when players’ bodies are often not in tune with the demands of the sport¹.

As was the case for hamstring injuries, a previous oblique injury was a primary risk factor for re-injury. Approximately 55% of players with a history of oblique injury experienced a second oblique injury¹.

These data led several in the sports media to declare 2011 as the “year of the obliques.” While the media reported that the number of oblique injuries in MLB had skyrocketed between 2009 and 2011, research shows that this was not the case. Oblique injuries are not new. MLB medical personnel started tracking them in 1991 and found that the number of oblique injuries remained fairly constant for 20 seasons². Over the course of those 20 seasons (1991-2010), oblique injuries accounted for a total of 393 abdominal strains resulting in an average of 30.6 days on the DL. The non-dominant was injured over 70% of the time and 12% of players experienced recurrence of injury after attempting to return to play.

Fast forward to 2017 and once again, some in the media are proclaiming that we are in the midst of another “oblique crisis”^3-5. While there are no official data to provide an accurate number of the oblique injuries that have occurred so far in 2017, fantasy websites⁶ indicate that there have been fewer than 20 reported cases of oblique injuries through the first half of the 2017 season. Likewise, recent research indicates that there were no spikes in oblique injuries among MLB players in the five seasons between 2011 to 2015⁷. Oblique injuries are debilitating and can have extremely negative effects on personal and team performance, but there is little evidence that there has been a significant increase in them in the last 2.5 decades^{2, 7}.

In fact, recent research on data collected since the Health and Injury Tracking System (HITS) was created and implemented by MLB in 2010 indicates that the number of oblique injuries has remained fairly constant over the past five years⁸. Inspection of Figure 1 shows that after an initial rise in 2011, there was a decline in the number of oblique injuries among MLB players each year between 2011 and 2015.

Further inspection of the data collected by HITS between 2010 and 2015 indicated the data obtained in the 20 years before the introduction of HITS were consistent with that obtained between 2011 and 2015⁷. Specific findings of the more recent study included the following:

• There were 996 oblique strains reported among 347,609 appearances by MLB players in 24,298 games resulting in an injury rate of one oblique injury for every 1342 appearances.

• The 996 oblique strains occurred in 259 MLB players (26%) and these players missed on average 23.7 days.

• Approximately 10.5% of these 259 players were reinjured within a 428 days of the initial injury. Thirty-eight percent (38%) were reinjured in the same season and 61% recurred in a subsequent season.

• The non-dominant side was injured in over 72% of batters and 82% of pitchers and took approximately 5 days longer to recover than injuries to the dominant side.

• The most common mechanism for injury was batting (45.7%) followed by pitching (34.9%). Approximately 6% of injuries were the result of non-pitching throwing while weightlifting was responsible for less than 1.5% of all oblique injuries.

• Starting pitchers were injured more often (62.6%) than relief pitchers (37.4%) and spent more days on the DL (27.4 vs. 23.8)

• The majority of injuries (78.3%) occurred during the season followed by spring training (19.7%) and the post-season (1.9%).

• When comparing injuries from month to month, there was a slight trend toward decreased injuries as the season progressed. Most of the injuries (37%) occurred during the first two months of the season.

• Two significant findings in this study were that there were measurable decreases in both the number of oblique injuries and days missed each year. These findings are significant because they indicate that following the initial research on oblique injuries started in 1991, there has been increased attention paid to these injuries and additional focus has been placed on comprehensive, preemptive core training as a potential means to prevent injury.

• Although the rate of oblique injuries is on the decline in MLB, this is not the case for MiLB, and these injuries continue to represent a significant source of time out of play in professional baseball.

Subsequent posts will examine the potential causes of oblique injuries and provide suggestions for developing a comprehensive core training program to help reduce the risk of oblique injuries.

References

1. MLB Medical Aspects Research Council, 2011.

2. Conte, SA, et.al. Abdominal muscle strains in professional baseball. Am J. Sports Med. 40:650-656, 2012.

3. Oblique injuries will keep Chris Davis out indefinitely, https://www.pressboxonline.com/2017/06/17/oblique-injury-will-keep-orioles-chris-davis-out-indefinitely

4. Cole Hamels expected to miss 8 weeks with oblique strain. https://www.mlbtraderumors.com/2017/05/rangers-place-cole-hamels-on-10-day-dl.html

5. Miguel Cabre4a out with oblique injury. http://www.scout.com/mlb/rumors/story/1779099-miguel-cabrera-out-with-oblique-injury

6. Injury report. http://mlb.mlb.com/mlb/fantasy/injuries/

7. Camp, CL., et. al., Epidemiology and impact of abdominal oblique injuries in major and minor league baseball. Orthop J sports Med. March 2017.

8. Pollock, KM, et. al., Developing and implementing Major League Baseball’s health and injury tracking system. Am J Sports Med. 183:490-496, 2016.

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Gene Coleman, Ed. D., RSCC-E, FACSM, was the Head S&C Coach for the Houston Astros from 1978-2012, has been a strength and conditioning consultant for the Texas Rangers since 2013 and is currently Professor Emeritus in the Exercise and Health Sciences Program at the University of Houston – Clear Lake. Jose Vazquez, PT, RSCC is Head Strength and Conditioning Coach, Texas Rangers.