ASEPTIC LOOSENING OF CEMENTED TOTAL HIP ARTHROPLASTY – THE INFLUENCE OF NON-STEROIDAL ANTI-INFLAMMATORY DRUGS AND SMOKING

Abstract

Introduction: Non-steroidal anti-inflammatory drugs (NSAIDs) are inhibitors of cyclooxygenase activity and are potential therapeutic agents in the prevention of aseptic loosening. Cigarette smoking is a risk factor for decreased proximal femur bone density. We investigated whether the clinical variables of NSAID usage and cigarette smoking are possibly linked to aseptic loosening around total hip arthroplasty (THA).

Methods: Retrospective review of records and radiographs of all patients attending for follow-up between August 2002 and 2003 who had undergone THA. Age, gender, primary and revision surgery details, radiographic parameters as detailed above, smoking history and NSAID usage history were recorded. Logistic regression analysis was used to determine the presence of associations.

Results: 224 patients were recruited to the study: 143 to the control group with a mean time of THR survival of 14.6 years and 81 to the aseptic group with a mean time to THR failure of 5.1 years. 130 patients had never smoked, 69 were ex-smokers and 25 were smokers (average of 15.5 cigarettes/day). 13.6% of patients in the study group were smokers and 10.5% in the control group. The average duration of NSAID usage pre-operatively was 3.4 years and post-operatively was 4.4 years. Using the logistic regression model, amount of cigarettes smoked, years as a non-smoker and length of usage of NSAID were not found to be associated with aseptic loosening

Discussion and conclusions: We found no such statistically significant relationship with regards to smoking habit or NSAID usage as either protective or risk factors.