Interposition Arthroplasty CMC Joint Denial

Question:

Our surgeon documented an interposition arthroplasty and removal of both the trapezoid and trapezium bones. I reported CPT code 25447 for the arthroplasty and 25210-59 for the removal of the trapezoid (in this case the second bone). I know CPT code 25447 includes the removal of one bone but not both. I coded this according to CPT rules as the patient is not Medicare.

Answer:

Thank you for your inquiry. Without seeing the operative note the coding is correct as shared.

KZA recommends you appeal using the AAOS Global Service Data Guide summary for CPT code 25447. It specifically states that the removal of either the trapezium or trapezoid is included in CPT code 25447. The key is the term “or”. Bone bones are not typically removed, and removal of the second bone requires additional work for the surgeon.

The use of modifier 59 is correct based on CPT rules of “different structure.”