['It is unclear when routine workup of postoperative pyrexia (POP) following total joint arthroplasty (TJA) should be performed.', 'A retrospective electronic database search was conducted on 25,558 consecutive patients undergoing primary or revision TJA between June 2001 and June 2013. We identified patient demographics, procedure type, characteristics of feverish patients, and febrile complications. The estimated costs for chest x-ray (CXR), urinalysis, urine culture, and blood culture were investigated.', 'POP occurred in 46% of TJAs. A total of 11,589 separate workups were performed in 90.5% of POP patients, of which 2.4% were positive. Urinalysis, urine culture, blood culture, and CXR were positive in 38.7%, 9.5%, 7.0%, and 0.2%, respectively. Febrile complications occurred in 4.5% and the infectious complications rate was 2.0%. The positive rate of fever workups was significantly higher in patients with the first POP occurring after postoperative day 3, POP > 102°F, multiple fever spikes, and patients undergoing revision TJA. Multivariate logistic regression revealed that the time of first POP, the maximum temperature, multiple fever spikes, and revision TJA were independent predictors of febrile complications. The estimated cost for 11,319 negative workups in patients with POP was $4,636,976.80, with CXR costing $4,613,182.00.'] Does routine Workup of Postoperative Pyrexia Following Total Joint Arthroplasty be Only Necessary in Select Circumstances?