An osteochondral lesion of the talus in ankle fracture needs appropriate treatment to prevent traumatic arthritis. Despite the high incidence of an osteochondral lesion in cases of ankle fracture, it is difficult to identify the location of the lesion during open fracture reduction due to limitation of the surgical approach. Therefore, we reviewed retrospectively the MRIs of ankle fractures to determine the incidences and locations of osteochondral lesions of the talus according to ankle fracture injury mechanism.

The MRIs of forty patients with ankle fractures were reviewed. Locations of osteochondral lesions were divided into nine areas; i.e., medial, central, lateral and anterior, central, posterior. Injury mechanisms were divided into supination and pronation groups.

Twenty eight (70%) out of 40 patients with ankle fractures had an osteochondral lesion of the talus. Thirteen (46%) patients were allocated to the supination group and 15 (54%) to the pronation group. Lesion locations were; 7 cases of lateral, 1 central, 5 medial and 8 posterior, 3 central, and 2 anterior for supination injury. In cases of pronation injury, 13 were lateral, 1 each central and medial, and 9 posterior, 5 central, and 1 anterior. The incidences of osteochondral lesions were significantly different at the lateral and central areas, and also between the posterior and anterior areas in both the supination and pronation groups.

For osteochondral lesion in cases of ankle fracture, careful observation of the posterior and lateral areas of the talar dome should be performed and additional treatment should be added for the lesion if required.