Osteochondritis Dissecans (OCD)
What is OCD?
Osteochronditis dissecans (OCD) is a condition in which the bone that supports the cartilage inside a joint undergoes softening. This softening is caused by a disruption in the blood flow to that area of bone. Over time, if left untreated, this can lead to damage to the overlying cartilage of the joint. Loose pieces of bone and cartilage can even break off into joint, and arthritis may develop long-term.
What causes OCD?
No one knows the exact cause, but it has been associated with both acute injuries and long term repetitive impact to the joint (overuse injuries). It may also be related to problems with blood supply to the bone.
Is OCD common?
OCD is a relatively rare problem, affecting far less than 1% of the population. It most commonly presents in adolescents (ages 12 – 19 years).
Which joints are most commonly affected?
The knee, ankle and elbow are the most commonly affected joints.
What are the signs and symptoms of OCD?
Not all OCDs cause signs or symptoms. The most common symptoms include knee pain, usually worse with increased activity, knee swelling, and possibly clicking and popping sensations. These may be preceded by a small injury that seemed to get better on its own.
The signs and symptoms of an acute injury to cartilage, on the other hand, are more obvious. There is usually a known twisting or contact injury to the knee, with rapid knee swelling and difficulty putting weight on the extremity. There may also be a sensation of clicking and locking of the involved joint.
What are the treatment options for OCD?
Children with growth remaining in their knee (boys below age 16 and girls below age 14) will often be treated without surgery. Resting from impact activities (like running and jumping) is recommended for at least 3 months. Many physicians will also recommend crutches, bracing, and or casting.
However, if the OCD does not heal, or if it is “unstable” upon presentation, surgery may be required.
The surgical choices to treat OCD depend on whether the OCD is firmly in place (stable) or threatening to loosen or dislodge (unstable). The following are a few examples of the many surgeries that are currently available to treat OCD.
- If the OCD is stable, the goal of the surgery is to help the OCD heal. This is most often done arthroscopically, with small incisions assisted by camera and small tools. A small pin is used to make drill holes to help encourage blood to flow to the area to heal the bone and cartilage.
- If the OCD is unstable, the point of the surgery is to make it firm or stable. A screw or dart may be used to hold the OCD in place to help it heal.
- If the bone and cartilage have broken off, and cannot be fixed, the goal of surgery is to place new cartilage in the hole.
- This can be done by ‘microfracture’, or stimulation of the bone, to make new scar tissue that acts like cartilage.
- Cartilage and bone may be moved from an area of the knee that does not need it, this is called osteochondral transplantation, or ‘OATS’. Cartilage and bone from a cadaver may alternatively be used to fill the hole.
- Lastly, the patient’s own cartilage may be sent to a lab and used to grow new cartilage that may be put back into the patient a few months later. This is called autogenous chondrocyte implantation, or ‘ACI’.
Can OCDs come back?
Once an OCD is healed, we do not believe that they can “come back.” However, sometimes an OCD acts like it has healed, or looks like it has healed, when in fact it has not. In this case, there may be a misconception that the OCD has “come back.”
Does OCD run in families?
There are some reports of families that have many cases of OCD. However, most patients with OCD do not have family members with OCD’s, so there is not thought to be a strong genetic or family disposition for OCD.
If I have an OCD in one joint, what are the chances I have one somewhere else?
OCD of the knee is thought to be bilateral, or in both knees, about 1 out of 4 times. However, there is no known link between OCD of the knee and OCD of other joints.