Table 2.

Detailed specifications of the indications for CTA and surgeries.

A: indication	Number of cases (n = 79)
OCL → fragment instability? (Figure 4)	n = 21
OCL → extend?	n = 16
Subchondral cyst or ganglia → fissural defect? (Figure 1)	n = 13
Subchondral BMEL → fissural/cartilage defect? (Figure 2)	n = 7
After cartilage repair surgery	n = 13
Bone necrosis/infarct → cartilage involvement?	n = 3
Tumora	n = 2
No findings on MRI but persistent complaints → cartilage defect?	n = 4
B: previous surgery	Number of cases (n = 33)
Osteochondral transplantation	n = 9
Autologous chondrocyte implantation	n = 2
Biomatrix implantation	n = 2
Retrograde drilling	n = 5
Curettage of ganglion/cyst and spongiosa graft	n = 4
Surgical treatment of ankle fractures	n = 7
Tumor surgery (giant cell tumor)	n = 1
Arthroscopy (debridement, shaving)	n = 3
C: surgery after CTA	Number of cases (n = 17)
Osteochondral transplantation	n = 2
Microfracturing/antegrade drilling	n = 3
Spongiosa graft	n = 5
Only chondral and osseous debridement	n = 4
Metal implant removal	n = 2
Syndesmosis reconstruction	n = 1

A: indications including clinical queries (→); B: previous surgeries; C: surgeries after CTA.

^aTumors were one chondroblastoma at the talus and one giant cell tumor at the tibia.

OCL: osteochondral lesion; BMEL: bone marrow edema-like lesion.