Fibromyalgia has recently emerged as a diagnosis of exclusion for patients with chronic, widespread pain. We investigated the influence of this comorbidity on outcomes of total knee arthroplasty (TKA). We matched 59 patients (90 knees) who underwent primary TKA with a diagnosis of fibromyalgia to control patients who underwent the same surgery. Postoperative satisfaction and functional outcomes were assessed using a Likert scale and the SF-36 survey, respectively. At 3.4 years' follow-up, fibromyalgia patients were less satisfied with TKA than control patients, and had lower preoperative and postoperative SF-36 scores. They demonstrated improvement comparable to that of controls following TKA, however. Fibromyalgia patients appear to show improvement comparable to that of controls following surgery. This syndrome should not be considered a contraindication for surgery.