The knee is the largest and one of the most complex joints in the human body. It consists of 4 bones, multiple ligaments, muscles and tendons, cartilage and soft tissue. The boney structures of the knee consist of the patella (knee cap), Femur (thigh bone), Tibia and Fibula (lower leg bones). The smoothness motion of the knee is accomplished through articular cartilage and fibrocartilage. Articular cartilage is the protective covering over the ends of the bones. Meniscus or fibrocartilage is the additional type. The purpose of your two meniscuses (medial – inside and lateral – outside) is to act as cushions between your femur (thigh bone) and tibia (lower leg bone). Both kinds of cartilage allow the joint to glide permitting fluid motion during active and passive activities.
Osteochondritis Dissecans or OCD lesion is a condition that can occur and develop in children, adolescents and young adults from a decreased blood supply to a specific area of bone affecting the cartilage site. The lack of blood supply causes the cartilage to become damaged and crack and loosen. This does occur in other joints of the body but is more common in the knee. Non-surgical treatment typically consists of partial to non-weight bearing for a period of time, physical therapy, rest and anti-inflammatory conditions. In cases of traumatic injury or in older patients these defects can be surgically repaired or replaced through procedures in which cartilage is transplanted from a cadaver or your own cartilage is grown in a lab and placed back into the area of defect. Above is a photo of a typical OCD lesion within the knee.