Question: The patient had an acetabuloplasty with resection of the femoral head. While still in the global period, the physician removed the spacers and performed a total hip arthroplasty (THA). Should this be coded as a THA or a revision THA, and what modifiers should I use? Michigan Subscriber Answer: If the surgeon was revising a previous total hip replacement, you would report 27134 (Revision of total hip arthroplasty; both components, with or without autograft or allograft). However, 27132 (Conversion of previous hip surgery to total hip arthroplasty, with or without autograft or allograft) is appropriate in the scenario the subscriber outlined because the physician is performing a THA on a patient who has undergone a previous hip procedure. You should append modifier -58 (Staged or related procedure or service by the same physician during the postoperative period) to the THA code because this was presumably a planned or anticipated procedure.