Without more details to work with, it appears that your surgeon was treating an arthritic joint, during which the femoral notch region was treated by removal/debridement of scar tissue and removal of an osteophyte/spur of the femoral notch, which is a very common finding in this condition. I would tend to believe that more was done in the way of joint "debridement" of the arthritis than just the femoral notch region. In essence, this procedure should be called an "Arthroscopically Performed &/or Assisted Arthroplasty" of the knee, which is not a procedure for which there is a CPT Code (surprise). Having done my share of these cases, it usually involves a variety/multitude of procedures including synovectomy (limited (29875) or more likely extensive/major of several compartments (29876)), chondroplasty (29877) of several areas/compartments of degenerative articular cartilage disease (chondromalacia), and debridement/removal of osteophytes/spurs of the patella, femur (condyles and notch), and tibia (usually in the tibial spine area), and treatment of degenerative meniscal tears (29880/29881: meniscectomies), and in multiple compartments. Of the codes available for arthroscopic knee surgery, none of them adequately cover all that is done in these cases. So what you are left with is listing multiple codes for all the various types of procedures done with one or more Modifiers such as 22, 51, and even 59 (if one of its variant applies). The 29877 code "mentions" debridement in its descriptor, but tends to emphasize the debridement of articular cartilage (chondroplasty) more. As such I don't think that this code is adequate for covering all that is often done in these complex cases/procedures. The term "Debridement" is really quite vague and general, and would include the removal of any and all types of tissue that warranted removal, not just articular cartilage. As it is written, I would restrict the use of 29877 to the debridement of diseased articular cartilage (chondroplasty). Of course then you have to cross check all the NCCI Edits to see what you are left with.
As for the case in question, I would recommend reviewing the Operative Report to get the "whole picture" and whatever was done in the femoral notch would be included in the "whole picture." I would be surprised that the femoral notch was the only joint region that was treated.
Although I had not really considered an Unlisted Procedure, arthroscopic (29999) as a way to "bundle" all of these procedures into one code, I can't really argue with it as an alternative concept. As for "pairing" it with another comparable code, the best and most inclusive would be 27447: Arthroplasty of the knee (essentially "all compartments") which in its descriptor does not absolutely require the insertion of prosthetic components. In Orthopedics, the term "Arthroplasty" is defined/means a rather extensive "open debridement" of a joint (usually arthritic), but does not necessarily mean or require the insertion/placement of one or more prosthetic components. At one time there was a code for Knee Joint Arthroplasty (not requiring or mentioning prosthetic component placement), but that particular code is no longer in CPT.
This is a very complex situation to deal with, particularly as it applies to the arthroscopic treatment of arthritic joints, the knee being the most common, and the coding for it. There should be a code for this extensive procedure, but Hell will freeze over before that happens.
I hope this sheds some light on this query.
Respectfully submitted, Alan Pechacek, M.D.