My knee hurts and no one takes me seriously – Osteochondrosis dissecans in growing youths and children
Bone pain experienced during sports is not always just harmless growing pains. Osteochondrosis dissecans typically occurs on joint surfaces that are subject to repetitive stress (ankle, femoral condyle, elbow). This can lead to a disturbance of the blood supply in the growth cartilage below the joint cartilage, which causes cells in this cartilage layer to die. This can only be confirmed via MRI. With increasing growth and ossification, this defect becomes located in the bone core of the epiphysis and thus becomes visible on an x-ray. As long as the overlying articular cartilage is intact and the demarcated piece is stable, there is typically no swelling or blockage of the joint. At this point, complete healing with open growth plates is still possible by reducing strain. In addition, vitamin D deficiency is being discussed as a cause for a lack of bone repair.
If the disease is not detected at this stage, the fragment can be further damaged by prolonged athletic exertion and thus become more mobile. As a result, the overlying articular cartilage is exposed to ever-increasing shear forces, which at some point can no longer be withstood, which in turn leads to the formation of cracks. This causes synovial fluid to enter the defect, resulting in a bulge that mechanically irritates the joint and causes blockages or swelling. At this point, healing without surgical intervention is unlikely. With further weight bearing, the fragment may become a loose body (“joint mouse“). Because joint-supporting cartilage and bone are involved, this leads to premature wear and tear of the joint. In this case, the goal of surgery is either to anchor the fragment stably again (e.g. with screws) or, if it is already too badly damaged, to fill the bone defect with bone from another region and then to close it with a chondroplasty made from harvested cartilage cells and a stabilising membrane. But the overarching goal should be to identify the problem while it can still heal without consequences.
