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from the American Academy of Orthopaedic Surgeons

Diseases & Conditions



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Throwing Injuries in the Elbow in Children

With the start of baseball season, doctors frequently see an increase in elbow problems in young baseball players. 

While common in baseball players — especially pitchers — these same elbow injuries also occur in young athletes who participate in softball, water polo, tennis, volleyball, and other sports with repetitive overhead throwing or hitting. 


Your elbow joint is a joint made up of three bones: the upper arm bone (humerus) and the two bones in the forearm (radius and ulna). Muscles, ligaments, and tendons hold the elbow joint together and provide stability during movement.

The elbow is a combination hinge and pivot joint. The hinge part of the joint lets the arm bend like the hinge of a door; the pivot part lets the lower arm twist and rotate. Several muscles, nerves, and tendons (connective tissues between muscles and bones) cross at the elbow.

Elbow anatomy

Anatomy of the elbow, including the bones and major ligaments and nerves


"Little Leaguer's elbow" and osteochondritis dissecans are two examples of conditions that affect pitchers and other players who throw repetitively. A few other common elbow conditions are also detailed below.

Epicondyle Apophysitis (Little Leaguer's Elbow)

This injury occurs when repetitive throwing creates an excessively strong pull on the tendons and ligaments of the elbow, putting stress on the growth plate on the elbow. The young player feels pain at the location of the growth plate, the knobby bump on the inside of the elbow, which is vulnerable to injury because it is weaker than the ligaments and muscles that attach to it.

Little leaguer's elbow can be serious if it becomes aggravated, especially if the child ignores the pain and plays through it. Repeated pulling can tear ligaments and tendons away from the bone (see UCL Tears below. The tearing may pull tiny bone fragments with it in the same way a plant takes soil with it when it is uprooted. This can disrupt normal bone growth, resulting in deformity.

Osteochondritis Dissecans

A less common condition called osteochondritis dissecans is also caused by excessive loading, such as throwing and tumbling, and may be the source of the pain on the outside of the elbow.

Muscles work in pairs. In the elbow, if there is pulling on one side, there is pushing on the other side. As the elbow is compressed, the joint smashes immature bones together. Over time, with repetitive smashing, the bone and cartilage can loosen or fragment (break apart). The resulting condition is called osteochondritis dissecans.

X-ray showing effects of excessive throwing

X-rays of the right elbow joint of an 8-year-old baseball pitcher show irregularity of the humerus where it meets the bones of the forearm (see arrows). This irregularity is a side effect of excessive throwing in the immature elbow.

Ulnar Collateral Ligament (UCL) Tears

The ulnar collateral ligament is the major stabilizing ligament of the elbow in throwing. With repetitive throwing and poor mechanics, the ligament can tear, leading to severe pain and instability with all throwing activities.

Athletes will feel pain on the inside of the elbow, and they will frequently notice decreased throwing velocity.

Tendinitis or Muscle Strain

The flexor-pronator is a strong muscle of the upper forearm next to the elbow. It enables you to grip the ball and flex your wrist during throwing. With too much stress, this muscle can become inflamed and painful. 

With tendinitis, the athlete will have pain on the inside of the elbow when throwing, and if the tendinitis is severe, they will also experience pain during rest.


Little leaguer's elbow" may cause pain on the inside of the elbow. A child should stop throwing if any of the following symptoms appear:

  • Elbow pain or swelling, especially with loss of throwing velocity
  • Feeling a "pop"
  • Numbness or tingling in the arm
  • Restricted range of motion
  • Locking 


Left untreated, throwing injuries in the elbow can become complicated conditions. Continuing to throw may lead to major complications and jeopardize a child's ability to remain active in a sport that requires throwing.

Nonsurgical Treatment

Younger children tend to respond better to nonsurgical treatments. 

  • Rest. Decreasing the stress on the elbow remains the first line of treatment.
  • Apply ice packs to control pain and swelling. Do not put ice directly on the skin. 
  • If pain persists after a few days of complete rest of the affected area, or if pain recurs when throwing is resumed, stop the activity again until the child gets treatment.
  • Refine throwing technique.
  • Adhere to pitch counts and days of rest between pitching (below)

Surgical Treatment

Surgery is occasionally necessary, especially in girls older than 10 years and boys older than 12 years.

Depending upon a child's injury, surgery may involve:

  • Fixing a small piece of loose or broken bone
  • Bone grafting
  • Repairing a torn ligament


The number of pitches a child can safely throw daily in a game depends on the child's age. Generally speaking, the recommended maximum number of pitches is:

  • 50 for children ages 7 to 8 years
  • 75 for children ages 9 to 10 years
  • 85 for children ages 11 to 12 years
  • 95 for children ages 13 to 16 years
  • 105 for children and young adults ages 17 to 18

Source: PitchSmart

Even more important, young pitchers must get enough days of rest between pitching. Comprehensive pitching guidelines — including pitch count limits and required rest recommendations — have been developed by USA Baseball and Major League Baseball to help protect children from injury.

OrthoKids logo

Learn more about pediatric musculoskeletal conditions and injuries at POSNA's OrthoKids website.

Last Reviewed

June 2023

AAOS does not endorse any treatments, procedures, products, or physicians referenced herein. This information is provided as an educational service and is not intended to serve as medical advice. Anyone seeking specific orthopaedic advice or assistance should consult his or her orthopaedic surgeon, or locate one in your area through the AAOS Find an Orthopaedist program on this website.