Orthopedic Coding Alert

Question: Notes indicate that the orthopedist performed an arthroscopy on a patient’s right knee. What is the correct code for this scenario?

Minnesota Subscriber

Answer: Which code is the correct one is a fairly open question without much more information. But here’s the basics of choosing the correct knee arthroscopy code.

Diagnostic: When the orthopedist performs a diagnostic knee arthroscopy, coding is easy. You’ll choose 29870 (Arthroscopy, knee, diagnostic, with or without synovial biopsy (separate procedure)).

Surgical: When the orthopedist performs a surgical knee arthroscopy, coding is … not as easy. You’ll choose from codes in the following ranges:

• 29866 (Arthroscopy, knee, surgical; osteochondral autograft(s) (eg, mosaicplasty) (includes harvesting of the autograft[s])) through 29868 ( … meniscal transplantation (includes arthrotomy for meniscal insertion), medial or lateral).
• 29871 (Arthroscopy, knee, surgical; for infection, lavage and drainage) through 29887 (…  drilling for intact osteochondritis dissecans lesion with internal fixation).

Remember that an arthroscopy can start out diagnostic and end up surgical, and you’ll need to be ready for that situation. Also, keep in mind that all surgical arthroscopies include a diagnostic arthroscopy. For example, a patient with left knee pain reports to the orthopedist. During a diagnostic arthroscopy, the orthopedist finds evidence of chondral fragments. The orthopedist removes the fragments and completes the arthroscopy.

In this instance, the diagnostic arthroscopy code 29870 does not cover the encounter. You’d report 29874 ( … for removal of loose body or foreign body (eg, osteochondritis dissecans fragmentation, chondral fragmentation)) instead, with modifier RT (Right side) appended to indicate laterality, if the payer requires it.