Osteochondritis Dissecans

What is osteochondritis dissecans?

Osteochondritis dissecans is a joint disorder in which a loose piece of bone and cartilage separates from the end of the bone because of a loss of blood supply. The loose piece may stay in place or fall into the joint space, making the joint unstable. This causes pain and a sense that the joint is “catching” or “giving way.” These loose pieces are sometimes called “joint mice.”

Osteochondritis dissecans often occurs from repetitive motions that stress the joint. It affects both boys and girls, but is more common in boys 10 to 20 years old. It most often affects the knee (high-impact landings) and elbow (pitching and throwing).

Children with osteochondritis dissecans should be seen by a doctor right away. Without treatment, a loosened fragment of bone and cartilage may drift into the joint, causing it to slip, pop or lock. If this happens, the joint can get “stuck,” often at a 45-degree angle, until it’s moved manually or otherwise manipulated.

Meet Ryker

The football kicker’s dreams of playing for a Division 1 college team were nearly cut short by osteochondritis dissecans. After surgery, he came back stronger than ever.


Learn more about Ryker

What are the symptoms of osteochondritis dissecans?

The first sign of an osteochondritis dissecans injury may be a “popping” sensation in the injured joint. Most people can still use the injured joint, and many athletes keep playing. When symptoms of inflammation set in, the knee or elbow feels painful and tight. Your child may also have:

  • soreness or tenderness at the joint line
  • swelling or stiffness
  • difficulty straightening the joint fully
  • feeling like the joint is locking, “catching” or “giving way”
  • collection of fluid (“water on the knee”)

The signs and symptoms of osteochondritis dissecans can resemble those of other joint injuries. So it’s important that your child see a doctor for a diagnosis.

What causes osteochondritis dissecans?

Young athletes involved in high-impact sports can sustain an osteochondritis dissecans injury from repetitive motions that stress the joint. Typical sports that can put athletes at risk for osteochondritis dissecans of the knee are football, basketball, gymnastics, soccer and lacrosse. Sports that can increase the risk of osteochondritis dissecans of the elbow are squash, tennis, baseball and weight-lifting.

How we care for osteochondritis dissecans

The Boston Children’s Hospital Orthopedic Center provides comprehensive assessment, treatment and follow-up care to children, adolescents and young adults with osteochondritis dissecans.

With a goal of dramatically reducing overuse injuries like osteochondritis dissecans, members of our team often travel to local and regional schools, youth groups and sports clubs to teach leg strengthening and other techniques. We also conduct frequent safe-training programs and clinics for coaches.