Question: Do I document craterization of the talus and of the medial cuneiform with 28120? And can I charge with 2 units, or do I use separate codes? AAPC Forum Participant Answer: Using 28120 (Partial excision (craterization, saucerization, sequestrectomy, or diaphysectomy) bone (eg, osteomyelitis or bossing); talus or calcaneus) to document a partial excision of the talus or calcaneus would be correct, as the exception noted in 28122 (Partial excision (craterization, saucerization, sequestrectomy, or diaphysectomy) bone (eg, osteomyelitis or bossing); tarsal or metatarsal bone, except talus or calcaneus) would preclude using 28122 for the procedure when performed on the talus. Code 28122 may be reported for craterization of the medial cuneiform. As for the number of units you can bill for the service, according to Medicare, the maximum units of service that a provider can report for 28120 under most circumstances for a single beneficiary on a single date of service (known as medically unlikely edits, or MUEs) is two. So, you would not need a second code to bill two units of the procedure.