subtalar arthrodesis with arthrotomy and synovectomy

Per CCI, a subtalar arthrodesis (28725) and an ankle arthrotomy with synovectomy (27625 or 27626) are bundled. My physician says that he performs these two procedures in different joints so they can legally be unbundled. He says the arthrodesis is in the subtalar joint and the arthrotomy is in the tibio-talar joint. Is this really enough of a difference to unbundle? I don't want to not bill for something that could legitimately be unbundled but I am not sure this is enough of a distinction. Any thoughts would be appreciated.

re: subtalar arthrodesis with arthrotomy and synovectomy

Is he making two different incisions, if so, use mod 59 on the second procedure. Make sure he documents this well. Per my cci edits they can be used together with a modifier