Surgical Treatment of Osteochondral Lesions of the Talus in Young Active Patients

C artilage is a smooth, highly specialized tissue that coats the surface of the joint. Although it is only a few millimeters thick, it has exceptional stiffness to compression and resilience and is able to distribute loads1. It is susceptible to injury and is limited in regenerative capability2. The biological function of cartilage is to permit articular movement while minimizing surface friction, to absorb loads in the weight-bearing joints, and to reduce the stress on the subchondral bone. Figs. 1-A and 1-B Histological appearance of hyaline cartilage. Fig. 1-A After staining with safranin O (×30). Fig. 1-B After staining with alcian blue (×100). Hyaline (articular) cartilage consists of 70% water; 15% collagens (primarily type II); and 15% proteoglycans (in particular, aggrecan), noncollagen proteins, lipids, and inorganic material. Chondrocytes, the only cell type in this tissue, sit within the matrix of proteoglycans and collagen, which give the cartilage its compressive and tensile properties3 (Figs. 1-A and 1-B). Osteochondral lesions of the talus are defects of the cartilaginous surface and underlying subchondral bone of the talar dome4. The etiology of osteochondral lesions of the talus can be divided into primary and secondary. Primary osteochondral lesions of the talus represent chronic diseases of the subchondral bone, most likely due to a deficiency of the vascular supply. More rarely, they are described as associated with endocrine disorders and genetic abnormalities4. Primary osteochondral lesions were formerly described as osteochondritis dissecans5. Secondary osteochondral lesions of the talus most likely occur as a result of ankle injuries (ankle sprain or fracture), chronic instability, axial defects of the lower leg, or dysbaric osteonecrosis6,7. Because joint cartilage has a poor reparative capability, osteochondral lesions of the talus rarely heal spontaneously. More frequently, patients with osteochondral lesions of …