Osteochondritis Dissecans is a joint condition where bone underneath the cartilage of a joint dies due to a lack of blood flow. This bone and cartilage can then break loose, causing pain and hindering joint motion. In the elbow, this most commonly affects the capitellum, which is the rounded outer part of the humerus. It is frequently seen in adolescent athletes involved in repetitive overhead or weight-bearing activities, such as gymnastics or baseball.
Symptoms of OCD often develop gradually and are related to the stability of the affected bone and cartilage fragment.
Outer Elbow Pain: A dull ache on the lateral (outer) side of the joint that worsens during activity.
Locking and Catching: A sharp sensation that the joint is stuck, which occurs if a fragment has detached and is floating in the joint space.
Limited Extension: Difficulty fully straightening the arm.
Swelling: Intermittent puffiness or fluid buildup after physical exertion.
Tenderness: Localized soreness when pressing on the outer bony part of the elbow.
Early diagnosis is vital to prevent the fragment from detaching and causing permanent joint surface damage.
Physical Examination
X-rays: Initial images can often show a flattening or lucency (dark spot) in the bone, though early stages may not be visible.
MRI: This is the most effective tool for determining the stability of the lesion. It shows if the cartilage is intact or if fluid has leaked behind the fragment, suggesting it is loose.
CT Scan: Occasionally used to get a highly detailed look at the bone structure and to identify any loose bodies within the joint.
The treatment path is largely determined by whether the bone fragment is stable or unstable.
Stable (Cartilage Intact): Strict rest from sports (3 to 6 months), physical therapy, and activity modification to allow blood flow to return.
Unstable (Fragment Loose): Surgery to secure the fragment back into place using small pins or screws.
Detached (Loose Body): Arthroscopic surgery to remove the loose fragment and "drill" the bone to stimulate new cartilage growth.