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Tommy John Injury

It’s the championship game that he has been training for weeks. The 13-year old pitcher stands at the mound. He winds up, goes for the pitch, and POP!!! Uh oh. He cradles his arm and winces in pain. He is now on a long road to recovery from a Tommy John injury.

Elbow pain in young and seasoned athletes is nothing new. Its prevalence in the sport coincides with the surge in enrollments on high-level sports teams like traveling, championship, and high school sports teams. Baseball players are joining team earlier, they are playing harder, and they are getting injured.
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One of the most common causes of elbow pain in baseball players is Tommy John injuries or Ulnar Collateral Ligament (UCL) injuries.

What are Tommy John Injuries?

A Tommy John injury is an injury to the ulnar collateral ligament (UCL), or medial lateral ligament, the elbow. It is the fraying, partial tear, stretching, or complete rupture of the ulnar collateral ligament.

‘Tommy John injury’ got its name from a baseball pitcher in the 1970s. Tommy John was a pitcher for the LA Dodgers. He suffered from a ruptured tendon in his elbow. When Dr. Frank Jobe performed an ulnar collateral ligament reconstruction on the pitcher, the first of its kind at the time, the surgery was named after the southpaw pitcher.

Role of the Ulnar Collateral Ligament in Baseball

The UCL is vital for stability when throwing and pitching. It originates (or attaches) at the posterior distal side of the medial epicondyle. The insertion (moves with contraction) is at the base of the coronoid process. Three bands comprise the UCL: transverse, posterior, and anterior.

How does that affect throwing and pitching?

An overhead throw has five phases. The highest amount of stress on the elbow comes in the third phase – the acceleration phase. Here are the five stages of throwing to learn why.

baseball pitcher

Phase one: wind up

In this phase, the player is preparing to throw the ball. Movement in the upper body is generally low as the body gathers enough power to throw the ball. Usually you see the player pivoting the body and cradling the ball in their glove.

Phase two: cocking (early and late)

Cocking is when the arm is at the back to prepare to throw the ball. In the early cocking movement, the body is at the end of the windup movement and the stride is headed toward the batter. The arm is at 90-degree abduction, 30-degree horizontal abduction, and 50-percent external rotation.

In the late cocking phase, the front leg strikes the ground and the shoulder is at 90-degree abduction, 10- to 20-degree horizontal abduction, and 175-degree lateral rotation. As the body moves forward, the front shoulder is directed at the target, putting the shoulder in extreme external rotation.

Phase three: acceleration

In this phase, the pitcher is in the process of actually throwing the ball. The power is in the throw, and the shoulders, elbow, and muscles are most active at this critical phase.

During this time, extension can occur at a rate of almost 2500 degrees per second, all while at 20-degree flexion. For power and movement, the forearm is behind the upper arm so the elbow depends on UCL’s anterior band for stability.

The sheer force of the stress on the UCL is more than the tensile strength of the ligament. As a result, the UCL suffers small tears or complete ruptures.

Phase four: deceleration

In the fourth phase of throwing, the hand releases the ball with the muscles in the posterior quadrant controlling the rotation of the humeral head. During deceleration, the shoulder is abducted by 100 degrees. The joint experiences maximum loading.

Phase five: follow-through

The final phase of throwing allows the body to slow down and stop the forward motion of the body. Muscle activity returns to normal, and the player regains control of their body again.

Breaking down the five phases of throwing explains the mechanics of the pitch and the proper body positions. Even the most experienced baseball players can suffer injuries if the shoulder or elbow is overstressed. Injury can also occur when the movements are incorrectly executed.

Symptoms of UCL injuries

Not all elbow pain is a UCL injury that requires Tommy John surgery.

An MRI is required to diagnose Tommy John injuries. Some symptoms you should watch out for are:

  • Pain on the inside of the elbow
  • Decreased throwing ability and stability in the arm
  • Tingling in the latter two fingers: ring and pinky
  • Irritation or discomfort at the ulnar nerve (funny bone)
  • Loose elbow or unstable elbow

Athletes Most Susceptible to UCL Injuries

If the arms go up, the risk does too.

Activities such as running, batting, lifting weights (non-overhead exercises), and playing hockey don’t usually cause UCL injuries. Athletes who are most at risk of suffering elbow injuries that require Tommy John surgery are those who perform repetitive overhead movements that cause strain and stress on the elbow, such as:

  • Pitchers in baseball (softball pitchers are not at risk because they pitch underhand)
  • Catchers in baseball and softball
  • Gymnasts
  • Javelin throwers
  • Tennis players
  • Wrestlers
  • Football players, especially quarterbacks
  • Water polo players

Lyman (2012) found that half of youth pitchers experienced throwing arm pain at some point during their baseball seasons.

33 Things to Know About Tommy John Injuries (UCL Injuries)

That was only a quick recap of the injury.

There is a lot more to learn about the pervasive injury in throwing sports.

1.Elbow injuries are especially problematic for younger players and athletes. Risk of Elbow pain in youth baseball players is 20-30% for players age 8-12 years; 45% for players between 13 and 14 years old; 50% and higher for high school athletes (Gregory and Nyland, 2013).

2. Poor pitching mechanics and overuse often cause elbow injuries despite 31 % of coaches, 28% of players, and 25% of players believe overuse does not contribute to injury or increase risk of injury (Gregory and Nyland, 2013).

3. Gregory and Nyland also reported that an overwhelming number of participants, players, and coaches believe the only solution for UCL injuries is Tommy John surgery: 51%, 37%, and 30% respectively (Gregory and Nyland, 2013).

4. The elbow is most at risk for injury during late cocking and acceleration phase because the elbow experiences maximum elbow valgus stress (stress on medial collateral ligament).

This is how we do the Tommy John ligament stress test:

5. In 2012, 36 MLB players had Tommy John surgery. Note, this is just MLB, not minor league.

6. Many believe that having the surgery will improve pitching performance. It will not. In fact, returning to normal pre-injury pitching is only achieved with extensive physical therapy, hard work, and a little luck. Remember, most elite pitchers make it back, but not all. Read this  great piece by physical therapist Stephania Bell.

7. After a surge of Tommy John surgeries in the late 90s, Tommy John surgery is trending downward. 2016 experienced the lowest instances of Tommy John surgery since 2008.

8. MLB players are turning to alternative methods of treatment such as stem cell injections to repair partially torn UCLs. Some are also just forgoing surgery and doing intensive physical therapy like Masahiro Tanaka.

9. The MLB team with the highest number of players who have undergone Tommy John surgery is the Reds, with three pitchers going under the knife.

10. Players between the ages of 15 and 19 years are the most common patients for Tommy John surgery. About 60% of Tommy John surgeries performed in the US are on youth athletes in that age group according to a 2015 American Journal of Sports Medicine report.

11. It can take anywhere from 12 months to 30 months for an athlete to recover from Tommy John surgery. Returning to the field depends on the extent of the injury, the location of the injury, and adherence to recovery recommendations.

12. Players may experience a “pop” followed by pain and immediate swelling if a complete tear occurs.

13. An athlete may have an injury but not experience pain during normal daily activities. Pain will occur only during the overhead throwing movement.

14. UCL injuries may also be suspected in other ways apart from their painful symptoms. Limited throwing endurance and speed as well as elbow instability may occur instead.

15. Caution should be taken in youth athletes, especially if they play overhead sports year-round. Players need rest throughout the year. This used to be what off-season was for, but now that youth players have more opportunities to play during winter, summer, and fall, the risk for a UCL injury increases.

16. Youth pitchers require lots of rest. According to ASMI, young pitchers must have weekly and annual rests. They should abstain from any overhead throwing for 30 to 60 days per year,

and not pitch competitively for 4 months per year.

17. Pitchers should not be pitching every day of the week. In youth sports, pitchers should adhere to pitch counts to prevent injury from overuse.

See the pitching chart count from The American Sports Medicine Institute (ASMI):

Position Statement for Adolescent Baseball Players

18. Youth pitchers should be encouraged to pitch only at an age-appropriate speed and pitching technique.

19. The ASMI recommends youth pitchers pitch no more than 100 innings per year to avoid overuse injuries.

20. Youth players must first learn the fastball before progressing to more advanced pitching methods such as the forkball, curveball, knuckleball, and screwball. Progression is key, and it won’t happen in a single season. Gradual progression to advanced pitching methods takes years.

21. RICE is the most prescribed method for treating and recovering from a minor UCL injury. Rest, Ice, Compression, and Elevation reduces swelling and inflammation, but it is not enough for more serious injuries such as partial or full tears.

22. The main risk factor for UCL injury in pitchers is pitching velocity (Norton 2020).

23. The most effective ways to identify injury and the location of injury are with a valgus stress test and an MRI. A valgus stress test on the elbow is done in a clinic. A physician, sports medicine professional, or physical therapist tests the integrity of the elbow when the athlete is in a sitting position. The elbow is placed at a 20-degree elbow while the clinician palpates the medial joint line when the humerus is on full lateral rotation and the forearm is neutral. If the athlete experiences pain while the valgus force is applied to the area, the UCL is injured.

24. Not enough rest is one of the biggest mistakes young players, coaches, and parents could make. I mention all three, even though it is the youth athlete who needs the rest, because the coach and parents play a vital role in encouraging rest.

25. Players with injuries that occur at the point of origin recover easier than those with injuries at distal points where the ligament attaches at the ulna (the funny bone).

26. Too much rest may be counter intuitive to recovery. Physical therapy is a major factor in prevention and recovery. It helps strengthen muscle and correct mechanics.

27. Tommy John surgery will not improve pitching speed. Only strength training and conditioning for pitchers will improve speed and performance.

28. Regular physical therapy and proper strength training help players prevent elbow injuries, recover from elbow injuries, and correct pitching mechanics. Physical therapy for baseball players and pitchers improves proprioception –or a person’s sense of body movement and joint position– for better mechanics and movement.

29. The evidence is unclear about whether pitching from a mound or pitching from a flat ground surface contributes to or reduces the risk of UCL injuries in pitchers.

30. Throwing and pitching movements are not the only ones that contribute to UCL injuries. Power gripping and excess weight on a rotated elbow could also cause injury to the ligament.

31. Tommy John surgery is not always the answer for UCL injuries. Fortunately, the professionals have caught on this fact. Stress, stretching, and micro-tears could be corrected with physical therapy to improve the stability and integrity of the elbow for healthier pitches and longer baseball careers.

32. Height was also determined as risk factor. A study by Harada (2010) that found that height >150 cm doubled the risk for certain elbow injuries.

33. Playing for multiple teams is also deemed a risk factor (Norton 2020). Chalmers (2015) found after a multivariate analysis that pitchers were 22% more likely to have sustained a throwing arm injury if they reported pitching for more than 1 team at a time.

In an interview I had with Dr. Mark Schickendantz, Associate Professor at the Cleveland Clinic and Director for the Center for Sports Health, he said the biggest mistakes athletes, especially younger ones, make is not getting enough rest and pitching too much throughout the year. So, youth athletes are subjected to invasive surgeries at a younger age.

Injuries and surgeries are becoming an epidemic when prevention is possible. Surgery is not always inevitable.

Dr. Schickendantz expresses the need for more studies on proper pitching mechanics. More clinical studies are also needed to explore modifiable risk factors to reduce the staggering number of UCL injuries in youth athletes.

I agree and encourage players, coaches, and parents to take some initiative too. Everyone could explore other methods, such as targeted strength training and physical therapy to prevent and treat UCL injuries.

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1. Gregory, B., & Nyland, J. (2013). Medial elbow injury in young throwing athletes. Muscles, Ligaments and Tendons Journal, 3(2), 91–100.