Dose-dependent efficacy of diclofenac-cholestyramine on pain and periarticular ossifications after total hip arthroplasty: a double-blind,prospective, randomised trial

Introduction To investigate the efficacy of treatment with diclofenac-cholestyramine on postoperative pain and functional outcome after total hip arthroplasty, a randomised double-blind study was conducted.Materials and methods A total of 245 patients received postoperative treatment with 75 mg or 150 mg diclofenac p.o. daily for 14 days.Results Patients who received 75 mg diclofenac per day needed paracetamol as an additional analgesic significantly more often (p=0.0162) than patients who were treated with 150 mg diclofenac daily (75 mg twice a day). The incidence of adverse gastrointestinal events was significantly lower in the group receiving 75 mg diclofenac daily than in the group receiving the higher dose (23.1% vs 37.1%; p=0.025). Six months after the operation, no differences were observed between the two groups with regard to pain or functionality measured in terms of overall mobility of the hip. No patient of either group developed clinically relevant heterotopic ossifications.Conclusion Treatment with a dose of 75 mg diclofenac once daily—if necessary with the additional use of paracetamol—is a favourable option for the postoperative care of THA.