Posts in baseball
Imaging's Role in Youth Baseball

In our previous blog posts we have written on the limitations of MRI for many injuries and conditions.  In general, these expensive tests have high rates of false positives where patients without pain often have positive results including ligament/labrum tears or tendon changes.  The incidence of false of positives increases in athletes with the majority of major league baseball players, regardless of symptoms, demonstrating rotator cuff tears or labrum injury.   It appears these changes are no different in our little leaguers.  

An article in the Journal of Bone and Joint Surgery examined 10-13 year old little league baseball players.  Each player underwent an MRI on both elbows at the start of the season.   The authors found many of the players with or without pain had imaging findings in their elbow.  Adding to our existing data that many athletes have positive MRI findings without pain or injury.  Two factors were associated with a positive MRI and elbow pain including year round baseball play and working with a private pitching coach.  

Athletes are encouraged to work with a local Physical Therapist to treat their elbow pain and reduce their risk of throwing injuries. 

The Impact of Core and Leg Muscle Fatigue on Baseball Throwing Mechanics

As we move into Spring we begin to see our youth athletes return to the baseball diamond often with a sudden increase in practice volume.  The sudden increase in throwing volume, either in the field or on the mound, places the athlete's shoulder and elbow at greater risk of baseball injuries. The greatest risk factors for injury include throwing more than 80 pitches/game, playing baseball greater than 8 months/year, and pitching with arm fatigue. As discussed in our prior posts, an athlete's throwing velocity is driven by their legs strength and power. Athletes with leg weakness are more likely to suffer from progressive changes in performance and increased injury risks.

A recent study in the Orthopedic Journal of Sports Medicine authors analyzed the impact of fatigue on throwing velocity, accuracy, and throwing mechanics (Chalmers et al. 2016). Authors studied 28 elite adolescent (13-16 year old) pitchers as they pitched a simulated game (90 pitches). Each pitch was analyzed for velocity and accuracy while every 15th pitch was analyzed for pitching mechanics. As expected the velocity, accuracy, and mechanics suffered with increased pitch counts. Importantly, the authors showed the loss of velocity, accuracy, and biomechanics were preceded first by core and leg muscle fatigue.

This study adds to the importance of controlling pitch counts and treating the lower extremities in order to improve throwing performance and reduce injury risk.  

Sports Specialization and Injury Risk

With a changing in the seasons we also see a changing of the sports in our Boulder County student athletes.  Athletes previously focused on winter sports including swimming and basketball are now able to focus on spring sports including baseball and track.  Prior research shows athletes who change sports during the sports year have half the risk of injury compared to their peers who focus on one sport all year round.  Early sports specialization  in school sports places athletes at greater risk of overuse injuries during their seasons due to lack of recovery/rest periods, muscle imbalances, and repetitive sports movements such as pitching.  

A recent article in the American Journal of Sports Medicine adds further support to the risk of student athletes playing one sport year round.  Bell and colleagues studied over 300 athletes aged 13-18 from 2 high schools to determine the prevalence and impact of year round athletics (2016).  Athletes were classified in 3 groups including low, moderate, and high specialization based on their single sport participation.  Not surprisingly, athletes from larger high schools were more likely to specialize in one sport and these athletes reported greater rates of overuse injuries than their peers who played at smaller schools or multiple sports per year. Specifically, athletes playing one sport greater than 8 months per year were at greater risk of injury than athletes who participated in one sport less than 8 months of the year.  

Parents, coaches, and student athletes are advised to consider the risk of spending >75% of the year training for an individual sport.  Coaches and athletes are advised to schedule their training year based on periods of dedicated to both training and recovery.  

Improving Throwing Velocity

A common question we receive from young throwers and their parents is how to improve throwing velocity safely without undue stress on their arms.  Our prior posts on throwing have focused on reducing arm stress through injury prevention and lower quarter strengthening.  This post will focus on the research surrounding exercise programs designed to improve a thrower's velocity of their pitches.  Ellenbecker et al. previously reported the lower body contributes 50% towards hand forces, while the shoulder only contributes 15%  (JOSPT, 2007).  As we would expect whole body, multimodal training aimed at the entire body improves throwing velocity both in short and long term training programs.

A recent analysis of the available evidence in the Journal of Strength and Conditioning Research examined the training programs shown to have the greatest impact on ball velocity in baseball, softball, or tennis (Myers, N. 2015).  13 articles were included in the final analysis and included interventions from plyometric training, medicine ball throws, and traditional upper and lower body resistance training.  These articles were scored as moderate to high quality based on a methodological analysis.  The training programs included were as short as 6 weeks or up to 9 months in length in a periodization format.  

The authors noted improvements in ball velocity across sports if the athletes were given whole body exercises focused on the connection between the legs and arm.   Longer term programs were most often used but short term programs, 6 weeks, also reported improvements in velocity.  Specifically, in tennis a 17 and 20 mph serve speed increase was noted with a 4 and 9 month resistance training program.  Athletes should speak with a Physical Therapist to determine how to structure their resistance training, plyometrics, and medicine ball throws in order to have an optimal impact on their ball velocity.