Table 4: CT staging system for osteochondral lesions of the talus.
| Stage |
Definition |
| I |
Cystic lesion with intact roof |
| IIA |
Cystic lesion with communication to talar dome surface |
| IIB |
Open articular surface lesion with overlying nondisplaced fragment |
| III |
Nondisplaced fragment with lucency |
| IV |
Displaced fragment |
CT classifcation of OLT - Ferkel RD, Sgaglione NA, DelPizzo W. Arthroscopic treatment of osteochondral lesions of the talus: long-term results. Orthop Trans. 1990; 14:172-8.