Lay summary
19,300 hip or knee replacements are performed in Aotearoa every year. The lifetime risk of a prosthetic joint infection (PJI) is 2% and so many New Zealanders are diagnosed with PJIs each year. PJIs dramatically affect quality of life and are difficult to treat because the prosthetic joint is a foreign body which encourages bacterial biofilm formation. Combined surgical and prolonged antibiotic management is necessary but outcomes are generally poor with substantial variation (infection cure rates of 10-90%, median 50%, after two years) and healthcare costs are high. Existing guidelines for the management of PJI are informed by low-quality evidence with fewer than 1,700 participants ever enrolled into published randomised trials comparing PJI management approaches. Defining the optimal surgical and antibiotic approaches is a critical unmet need. We propose a large Bayesian adaptive platform trial which will address multiple questions simultaneously to identify the best management for people with PJIs.