A – yes.  
Evidence: A prospective study specifically titled “Is etoricoxib effective in preventing heterotopic ossification after primary total hip arthroplasty?” found that 62 % of patients had no heterotopic ossification (HO) six months post-THA and only mild Brooker grade 1–2 HO in the remainder; the authors concluded that “Etoricoxib seems effective in preventing heterotopic ossification” [Brunnekreef 2013, PMID 23359100]. Subsequent trials and series have reported similarly low HO rates and efficacy comparable to standard NSAIDs, reinforcing this positive finding [Winkler 2016, PMID 26728611; Oberberg 2021, PMID 33639986].