osteochondrosis dissecans (O. D.): Death of small cartilage-bone parts, preferably in the knee, ankle or elbow joint. When these parts detach from the bone union, they migrate as Joint mice (joint bodies) move around freely in the joint and lead to pain and symptoms of entrapment there. Younger adults are usually affected. Spontaneous healing occurs in young patients and small foci, otherwise surgery is usually required.
– Pain in the knee joint – Recurrent swelling (joint effusions) – Sudden joint blockages due to entrapment of the joint mouse (blockage), after shaking often solved again.
When to go to the doctor's office
In the next few days, in case of pain in the knee that lasts longer than 3 days.
Immediately in the case of painful movement restrictions of the knee associated with a blocking sensation.
Show background information
Death of small portions of cartilage/bone close to the surface occurs in various joints, most commonly in the knee joint (Fig.) at the inner roll of the thigh bone. The cause is not clear. According to a common theory, recurrent impulse loading of the knee joint is thought to play an important role. Such pulses occur especially in sports with repetitive stopping or impact movements (z. B. in soccer, tennis).
The dead piece of bone, which is usually the size of a lentil, detaches from the composite over time and wanders around in the joint as a joint mouse. This process initially causes little discomfort. Only when the mouse becomes wedged and causes a blockage of the joint, the disease becomes noticeable. In most cases, shaking or carefully bending and stretching the knee succeeds in freeing the mouse from the entrapment again and thus resolving the symptoms. However, if the joint mouse is left untreated for a long time, it often leaves behind damage to the remaining cartilage. If the mouse bed, i.e. the origin of the detached piece of bone (dissekat), is located in the main load-bearing zone, wear-related changes develop over time that can eventually lead to knee joint arthrosis. Especially in younger patients or small mice, the disease often stops at an early stage or even heals completely.
What the doctor does
Detection of the articular mouse is only successful with an X-ray if it contains bony parts. Purely cartilaginous mice can be visualized in magnetic resonance imaging.
Osteochondrosis dissecans starts when a piece of bone dies on the joint surface, typically in the area of the joint roll on the femur. The loosening piece of bone (dissekat) is marked with red arrows on the upper X-ray image. As the disease progresses, the dissecting bone detaches from the bone union; this is shown in the lower magnetic resonance image. Georg Thieme Publishing House, Stuttgart
The long-term treatment depends on the stage of the disease. If the dead piece of bone has not yet detached, sometimes 3 months of relief of the affected leg is sufficient for healing. All other cases require an operation in the course of a knee endoscopy (arthroscopy). In the case of fresh detachments, reattachment (refixation) of the mouse is often successful, whereas in the case of older joint mice, the only option is removal. In the second case, drilling into the mouse bed serves to stimulate the formation of replacement cartilage and thus fill the resulting hole in the long run. An alternative is to fill the defect with a cartilage graft. Also in early stages of the disease, the surgeon often drills holes to reconnect dead but not yet detached bone tie to the blood supply. surgeon removes cartilage-bone cylinders from little-used joint regions. inserted into the worn parts of the joint. There the cylinders heal. Replace the missing cartilage sections.
The prognosis depends mainly on the stage of the disease at the start of therapy. It ranges from complete healing to a permanent defect with the threat of arthrosis.