Baseball Injuries

Monday was Opening Day for the Brewers, which means that spring is finally here. In our physical therapy clinic, this is also about the time we start seeing an uptick in the number of high school and college baseball players who come to see us for elbow or shoulder pain.

So, why are shoulder and elbow pain so common in baseball?

Baseball pitch

 Baseball players, especially pitchers, typically have shoulders that are very flexible in external rotation (see picture to the right), which allows them to generate speed as they throw. Over time, they may develop stiffness into internal rotation (the opposite direction) due to tightness through the rotator cuff and other shoulder structures. This can lead to irritation and pain in the shoulder, as well as compensations at the elbow. In the cocking position (see picture to the right), the shoulder is stretched into maximum external rotation and there is also a lot of stress transmitted to the inside of the elbow. To tolerate this position hundreds or thousands of times over the course of a season, the arm needs a good balance of mobility of the joints and stability of the surrounding muscles. 

Overloading the arm with too many throws or throwing with poor mechanics can lead to injuries, especially in a growing athlete. Bones grow more quickly than muscles and this imbalance often leads to injuries near the growth plates of elbow or shoulder. Overuse can also lead to irritation and gradual tears of the rotator cuff muscles or labrum (cartilage) in the shoulder. Excess strain through the elbow can overstretch or tear the ligaments that stabilize the inside of the elbow. This is known as a “Tommy John” injury in baseball circles. If not caught early, some of these injuries may require surgery and a very long recovery.

How someone throws can also be a risk factor for shoulder or elbow injuries. Poor mechanics can lead to increased torque and strain through the shoulder and the inside of the elbow. A good pitching coach can identify throwing flaws and address them in order to prevent problems down the road. Learning good mechanics early on is much more effective–and safer–than waiting until there is a problem.

Preventing Injuries

Current research shows that a high number of pitches is one of the biggest predictors of having either shoulder or elbow pain. Baseball players between 9 and 14 years old were more likely to have shoulder pain if they threw more than 600 pitches throughout the course of the season and elbow pain with more than 800 pitches. In response to this research, Little League instituted pitch counts based off of the player’s age to avoid overtaxing growing joints. The following chart shows the maximum number of pitches allowed by age, as well as the recommended days of rest following a start.

Age                 Daily Max (Pitches) Required Rest (Pitches) Required Rest (Pitches) Required Rest (Pitches) Required Rest (Pitches) Required Rest (Pitches)
    0 Days 1 Day 2 Days 3 Days 4 Days
7-8 50 1-20 21-35 36-50 N/A N/A
9-10 75 1-20 21-35 36-50 51-65 66+
11-12 85 1-20 21-35 36-50 51-65 66+
13-14 95 1-20 21-35 36-50 51-65 66+
15-16 95 1-30 31-45 46-60 61-75 76+
17-18 105 1-30 31-45 46-60 61-75 76+

Information from

It is also important to gradually increase the amount of work the arm has to tolerate, especially at the beginning of the season, after injuries, or after time off. Gradually increasing the distance, speed, and number of throws over several weeks is important to avoid overtaxing the joints as they get used to the stress of throwing.

Along with gradually increasing the work on the arm, it is important to make sure that players, especially pitchers, have adequate rest. Pitching with a sore or tired arm is a significant risk factor for injuries. It is essential that pitchers have days off after starts to allow their arm to recover. Players that play on multiple teams may play year-round, never giving the arm sufficient time to rest and recuperate. It is recommended that athletes play their main sport a maximum of 9 months a year, as specializing in any sport year-round has been associated with a higher incidence of injuries. Players should have a 6-8 week recovery period following their season and focus on rest, off-season conditioning and injury prevention. This may also help with avoiding burnout.

Given the high demands on a baseball player’s arm, every player should have an exercise program that addresses their need for shoulder and elbow mobility and stability. A physical therapist can check for adequate range of motion and strength, take a look at the structures around the shoulder or around the elbow and develop a specific, individualized program to help keep the arm happy and healthy throughout the course of a long baseball season.


Brotzman SB, Manske RC. Clinical Orthopaedic Rehabilitation: an Evidence-Based Approach – Expert Consult. 3rd ed. Philadelphia, PA: Elsevier Mosby; 2011.

Straus LB. 2017 Little League Pitch Count Limits and Mandatory Rest Rules. MomsTeam. Published February 27, 2017. Accessed March 23, 2017.