Ankle scope with OCD

it was a 5mmx5mm tal dome lesion which was drilled out. When would you bill 29898- extensive debridement and when would you bill 29891-Arthroscopy, ankle, surgical, excision of osteochondral defect of talus and/or tibia, including drilling of the defect or 29892 Arthroscopically aided repair of large osteochondritis dissecans lesion, talar dome fracture, or tibial plafond fracture, with or without internal fixation (includes arthroscopy) Thanks

As you mentioned the ankle and not the subtalar joint and noted that some osseous defect was drilled out, then several CPT codes come to mind include:

29897 Arthroscopy, ankle (tibiotalar and fibulotalar joints), surgical; debridement, limited or

29898: Arthroscopy, ankle (tibiotalar and fibulotalar joints), surgical; debridement, extensive

To answer your question specifically would require knowledge of the size of the defect(s) and were they contained within the same bone or mutiple bones (e.g. tibial plafond and talar neck), was there a loss body in the joint, was the defect filled with bone, other graft material or prp (the latter perhaps not covered)?

If it was a simple drill out and scope out then 29897.

Even if you drilled out and filled one site w/some boney implant material, then 29898 would be appropriate.