Protocol for follow up of hip arthroplasty in the long term: effect on revision (WHISTLER study)

Total hip arthroplasty (THA) is highly successful for reducing pain and improving function, providing health-related quality of life benefit. Demand for THA is increasing with associated increase in revision hip surgery. Hip arthroplasty surveillance (long-term follow up) can identify asymptomatically failing THA to prepare for revision surgery, reducing potential for complications or complexity of surgery. However, it is unknown whether the surveillance of THA can be shown to improve the patient outcomes or reduce costs around revision surgery. With the current need to reduce unnecessary health consultations and to show the economic advantages of any service, the purpose of this study is to consider the relative effectiveness of hip arthroplasty surveillance on revision hip arthroplasty. This is a single-centre, observational study in which consecutive patients undergoing aseptic revision of THA over 12 months in a large orthopaedic unit will be considered for participation. Primary outcome measures will be change in each of three valid patient-reported scores from pre-operatively to 12 months post-surgery. Secondary outcomes will be the costs of treatment calculated using data obtained from the participants' hospital records and a self-report questionnaire. An exploratory approach will be used to investigate the effect of surveillance on the outcomes of interest. A linear mixed method model will be used to study the change in scores between baseline and 12 months. The economic evaluation will be a cost-utility analysis, which compares the value of alternative interventions by attaching costs to the quality-adjusted life years produced by each intervention.