Acute crystal arthritis mimicking infection after total knee arthroplasty

Total knee arthroplasty is the most effective treatment to relieve the pain associated with end stage arthritis of the knee.1 A reported 0.5-2% of people will develop sepsis of the implant, necessitating lavage and debridement of the affected knee with immediate or delayed removal of the implant.2 3 The key to successful management of implant sepsis is early and accurate diagnosis, which allows prompt treatment. Every patient with pain and swelling at the site of a total knee arthroplasty must, therefore, be assessed for infection.1 We report a case of a patient initially diagnosed as having implant sepsis who in fact had pseudogout of the knee. This shows the diagnostic difficulties and issues surrounding management that may arise when a patient presents with crystal arthritis at the site of previous joint replacement.