The top of the talus (ankle bone) is dome-shaped and is completely covered with cartilage. A talar dome lesion is an injury to the cartilage and underlying bone of the talus within the ankle joint. While symptoms may take months to develop, a talar dome lesion can cause pain, swelling, and more. This is why if you suspect some type of pain or injury to the ankle, it is important to have it diagnosed quickly. The place to start is with the skilled and experienced orthopedic specialists at OCC – Advanced Orthopedic & Sports Medicine Specialists in Denver, Parker, or Aurora, Colorado. Left untreated, a talar dome lesion can lead to long-term damage to the bone.
OVERVIEW
The talus is the uppermost bone in the foot that together with the tibia (shinbone) make up the ankle joint. The top of the talus is completely covered with cartilage—a tough, rubbery tissue that enables the ankle to move smoothly. When the ankle joint is injured, the cartilage may become torn or fractured and there is also injury to the underlying bone, causing a talar dome lesion. A talar dome lesion is also called an osteochondral defect (OCD), osteochondral lesion of the talus (OLT) or talar osteochondral lesion (OCL). “Osteo” means bone and “chondral” refers to cartilage. Osteochondral lesions can occur in any joint but are most common in the knee and ankle. Talar dome lesions account for 4% of all osteochondral lesions in the body. However, they have been found in more than 40% of patients after operative treatment of ankle fractures. About 85% of talar dome lesions are caused by a traumatic ankle injury.
ABOUT THE ANKLE
The ankle is the joint that connects the foot to the lower leg. Healthcare providers sometimes refer to it as the tibiotalar joint or the talocrural joint. The ankle moves in two directions: plantar flexion—down, away from the body, and dorsiflexion—up, toward the body. The ankles are made of bones, cartilage, ligaments, muscles, nerves, and blood vessels. Ankles are synovial joints. They’re made of a cavity in one bone that another bone fits into. Slippery cartilage covers the ends of the bones. A synovial membrane—a fluid-filled sac that lubricates and protects the joint—lines the space between the bones. This helps the joints move with as little friction as possible. The three bones that make up the ankle joint are the tibia (shinbone), fibula (calf bone), and talus. The talus sits between the tibia and fibula and the calcaneus (heel bone) below it. Even though it’s a small bone, the talus plays a big role in the ability to stand and move. It functions to support the weight of the leg, allow the foot to move up and down, maintain balance by moving the back of the foot side-to-side, stabilize the arch, and support ligaments in the ankle, heel, and foot.
WHAT IS TALAR DOME LESION?
If the ankle is injured through fracture or sprain, the talus and the tibia can collide against one another. When the tibia and talus collide, damage can occur to the cartilage of the talus resulting in a talar dome lesion. These lesions to the talar dome vary in severity from bruising of the cartilage to an actual fracture of the talar dome. In most cases, talar dome lesions form after another ankle injury, like a sprain, when the cartilage doesn’t heal correctly. When cartilage doesn’t heal correctly, it can soften and break off, and this in turn can cause debris to build up in the ankle joint, leading to further irritation. Talar dome lesions most commonly occur in two areas of the talus:
- The inside and top part of the lower bone of the ankle (the medial talar dome)
- The outside and top part of the lower bone of the ankle (the anterolateral talar dome)
Read more about Talar Dome Lesions on our new Orthopedic News Site – Colorado Orthopedic News. Schedule an appointment with a ankle specialist today.
