This query started as a diagnosis coding question (ICD-10), then morphed into a procedural question (CPT). ICD-10 really doesn't use the term "sinus," but kicks it over to Fistula instead. Fistulas don't just "happen" by themselves, but arise from some other tissue disease/disorder. In Orthopedics, this usually means bone, joint, bursa, muscle, tendon, etc., and is usually the result of a chronic process, which sooner or later becomes contaminated, then infected, and which finds its way to the surface through the subcutaneous tissue and skin, i.e. a chronic draining sinus/fistula. From the standpoint of diagnosis coding, it depends on the deepest musculoskeletal "tissue" involved and/or the "site of origin," such as bone, joint, etc. If it only involves the Skin and Subcutaneous Tissues, then that would be L98.8: Other Specified Disorders of Skin and Subcutaneous Tissue. If it originates from bone, then there is probably some element of Chronic Osteomyelitis such that M86.4: Osteomyelitis, Chronic, with Draining Sinus (Fistula) would apply. If it originates from within a joint, then M25.1: Joint Fistula would apply. Another issue is whether the Fistula/Sinus is the result or complication of a previous wound, surgical or traumatic, slow or non-healing? For a surgical wound, this would lead to T81.83: Persistent Post-procedural Fistula. For a traumatic wound, there is T79.81: Slow or Non-healing Traumatic Wound (with Fistula/Sinus). In other words, in order to code the "little picture," the fistula, you have to look at the "big picture," what happened before that resulted in this complication.
As for the surgical treatment/procedure, again it goes back to the history of how it all evolved. For a Surgical Wound with Dehiscence, then the 13160 would apply to repair of a deep and complex wound dehiscence, such as into a knee joint. The other Repair/Closure of Wound Codes (Simple, Intermediate, and Complex) generally leads one to think that these apply to Acute Wounds, but there is nothing that I can see in the "Instructions" that would Exclude chronic wounds such as those resulting in a Fistula, so I guess these Repair codes could be used. The 15002-5 codes refer to the exploration, debridement, etc. of a chronic wound situation for the "preparation" of the site for skin grafting, flap rotation, some other type of wound coverage, or Complex Closure/Repair. These codes are for the wound preparation only, but wouldn't include the Repair Procedure code itself.
Obviously this is not a simple topic with a simple answer, but maybe this discussion will help you some.
Respectfully submitted, Alan Pechacek, M.D.
icd10orthocoder.com