Growth Plate Injuries (Apophysitis) in Young Athletes

What is an apophysis?

During childhood and adolescence, the bones become longer and the muscles become larger. Tendons are the connection point between muscles and bones. The place where the tendon attaches the muscle to the bone is made out of cartilage and is called an apophysis. Chronic overuse injury to these sites that results in inflammation, pain, and/or weakness is called apophysitis.

How does injury to an apophysis occur?

The cartilage that makes up an apophysis is weaker than the bones and muscles. When a muscle contracts to move a bone, it tugs on the apophysis. When this tug occurs repeatedly or with too much force or suboptimal biomechanics, it can injure the cartilage over time and cause inflammation, swelling, and pain. In the worst cases, the cartilage can be pulled from the bone attachment site and is known as an avulsion fracture. Avulsion fractures are rare, but do occur when apophysitis is not treated properly and stress at these growth plates continues to the end point of breakdown or avulsion.

What are the symptoms of apophysitis?

Pain from apophysitis in its early stages occurs after or during an activity at the site of a muscle attachment. Sometimes swelling occurs as well. As apophysitis progresses through the stages of overuse injuries, often coaches, parents, or athletes themselves will notice that pain causes worsening of an athlete’s performance.  If apophysitis goes untreated and progresses it will often lead to either unremitting stage 4 pain or an avulsion fracture depending on the specific growth plate involved.

Who gets apophysitis?

Young athletes who are involved in sports or activities that require repetitions of the same action are more likely to have injuries. Some examples include throwing sports (like baseball or football) and jumping or running sports (like basketball, track, or soccer).

How is apophysitis diagnosed?

Often, apophysitis is a clinical diagnosis, meaning that the pain history, location of pain, and your doctor’s exam give enough information to make a diagnosis. If avulsion fracture or another diagnosis is considered, X-rays may be required. Rarely, MRI or CT-scan may be required.

How is apophysitis treated?

Rest and physical therapy are required to completely heal an inflamed apophysis and return back to sport successfully. Usually this process takes anywhere from 4-8 weeks depending on the stage of injury, but every athlete is different. Both rest and physical therapy are important aspects of healing and should be taken seriously in order to return to play. Physical therapy focuses on improving flexibility, joint stability, mechanics, and strength of the injured area to promote healing and to prevent re-injury.  Conservative return to play guidelines should be utilized by a pediatric sports medicine specialist who understands the fragility and pediatric growth plates.


By Becca Bramble, DO and Mo Mortazavi, MD