Medial epicondyle avulsion fracture

The forearm muscles anchored to the elbow at the medial epicondyle growth plate. A single, forceful contraction of these muscles can cause them to pull the growth plate away from the bone. This is called an avulsion fracture.

A. Boutwell

The medial epicondyle is the bony bump on the inner side of the elbow. In children and adolescents who are actively growing, there is a growth plate at the medial epicondyle. The growth plate is made up of cartilage cells, which are softer and more vulnerable to injury than mature bone. The forearm muscles that bend the wrist are anchored to the elbow at the medial epicondyle growth plate. A single, forceful contraction of these muscles can cause them to pull the growth plate away from the bone. This is called an avulsion fracture.

How it occurs

Medial epicondyle avulsion fractures most commonly affect adolescent baseball pitchers during periods of rapid growth, typically between 9 and 14 years of age. This is when the growth plate cartilage is most vulnerable to injury. One hard pitch can cause an avulsion fracture. The forearm muscles anchored to the elbow at the medial epicondyle growth plate contract forcefully during the pitching motion. Baseball players in other positions that require hard throws, such as shortstop, third base, and outfield are also vulnerable to this injury. Less commonly, it can affect athletes in other throwing or overhead sports such as football, water polo, and volleyball.

Signs & symptoms

The main symptom is sudden onset of severe pain on the inside of the elbow following a forceful pitch or throw. Some athletes feel or hear a pop at the time of the injury. There is usually swelling and some limitation of elbow motion. Occasionally the ulnar nerve, which sits next to the medial epicondyle, becomes irritated after an avulsion fracture, causing numbness and tingling in the forearm and fourth and fifth fingers.

Diagnosis

Your doctor will examine your child’s elbow and arm for tenderness at the medial epicondyle. An X-ray will show the avulsion fracture as a separation of the growth plate from the bone of the upper arm (humerus).

Treatment

Most avulsion fractures can be successfully treated with cast immobilization for 4-6 weeks. During this time ice can be placed on the elbow for 20-30 minutes every 3-4 hours while there is pain or swelling. After 4-6 weeks of immobilization, if X-rays show the fracture is healing, a course physical therapy is prescribed. While most avulsion fractures heal well with this treatment, those with a very wide separation on X-rays may require surgery. The recovery time after surgery is similar that for non-surgical treatment.

Returning to activity and sports

When your child achieves full pain-free motion of the elbow and adequate strength in the arm, upper back, and core muscles (usually after 3-6 weeks of physical therapy), a gradual return-to-throwing program is begun. It typically takes 4-6 weeks in this program before the athlete can pitch in games.

Everyone recovers from injury at a different rate. Return to your sport or activity will be determined by how soon the elbow recovers, not by how many days or weeks it has been since the injury occurred. The goal is to return your child to his or her sports as quickly and safely as possible. If your child returns to play too soon or plays with pain, the injury may worsen, which could lead to permanent damage and difficulty with sports.

Preventing medial epipcondyle avulsion fractures

Lots of pitching puts repetitive stress on the medial epicondyle growth plate, which can weaken it and make it more prone to avulsion fracture.

• The best way to prevent medial epicondyle avulsion fracture is to follow the attached guidelines for appropriate pitch count limits and proper rest between pitching appearances.
• DO NOT throw through pain. Pain is a sign of injury, stress, or overuse. Pushing through pain will only worsen the injury. Rest is required to allow time for the injured area to heal.
• DO NOT throwing breaking pitches (curveball, slider) before age 14.

How many pitches should youth baseball pitchers throw? The USA Baseball Medical and Safety Advisory Committee has published guidelines for maximum pitch counts based on age.

Maximum number of pitches

Rest for pitchers

A certain amount of repetition is required to develop the strength and skills needed to be a successful pitcher. However, adequate rest is as important as repetition. If rest is insufficient, skill development suffers and the risk for injury increases. A pitcher’s body muscles, tendons, and bone growth centers need sufficient time to cool down and re-charge for the next event. Pitchers should obtain at least 24 hours of rest after each pitching outing. Once removed from the pitching position, pitchers should not return to pitch in a later inning during the same game.

For pitchers age 7 to 16:

For pitchers age 17 to 18: