The codes for Open Treatment of a Tibial Nonunion start with 27720 (without bone graft), 27722 (with sliding bone graft), and 27724 (with iliac or other autograft). Unfortunately, the way CPT is written, 27720 includes Internal Fixation, but is written such that it implies that Compression Fixation Technique (i.e. Compression Plate and Screws) is the only method of fixation used/usable for this repair. This used to be true years ago, but certainly isn't true today. IM Nailing is a valid method of fixation/treatment of nonunion, if it can be performed. The CPT code 27720 needs to be updated to include this fixation method, or be written to include any type of, or "with internal fixation." Codes 27722 and 27724, as subtypes of 27720, would also include the method of fixation, but differ only in the type of bone graft used and its source. The code 27759 applies to Open Treatment of (acute/current) Tibial Shaft Fractures, but not Nonunions of old fractures.
I hope this helps.
Respectfully submitted, Alan Pechacek, M.D.