The objectives of this study were to determine the perioperative surgical and medical risks associated with sequential bilateral total knee arthroplasty (TKA) in patients > or = 75 years old and to assess their functional status and overall level of satisfaction at follow-up. Study participants were 82 consecutive patients > or = 75 years old who underwent a sequential bilateral TKA and 82 matched patients who underwent a unilateral TKA. There were 46 postoperative complications in the bilateral TKA group compared with 27 in the unilateral TKA group (P = .003). Postoperative cardiovascular complications were significantly greater in the sequential bilateral TKA group and were associated significantly with preoperative cardiovascular comorbidity. The mean Modified Hospital for Special Surgery knee score was rated as good (mean, 63.5 out of 80), and 95% of patients rated their knees as excellent or good at follow-up. Sequential bilateral TKA in patients > or =75 years old results in high patient satisfaction and good functional status at follow-up; however, there is an increased risk of cardiovascular complications during the postoperative period in bilateral sequential TKA patients when compared with a matched cohort of unilateral TKA patients.