Simultaneous single-stage versus two-staged bilateral total knee arthroplasty: a prospective comparative study

Abstract
Purpose The study aims to prospectively compare peri-operative morbidity and mortality of simultaneous single-stage bilateral total knee arthroplasty (SS BLTKA) with two-staged bilateral total knee arthroplasty (TS BLTKA) performed within 12 months of the first surgery. We hypothesized that SS BLTKA is as safe as TS BLTKA. Methods Patients with a minimum follow-up of 12 months were included in this study. Oxford knee score and quality of life index SF12 was compared between the 2 groups at six weeks and six month follow-up. Results SS BLTKA included 250 patients and TS BLTKA included 210 patients. The minimum time interval between two operations was three weeks (mean 1.6 months, range 3 weeks-12 months). There was no significant difference between the 2 groups in peri-operative mortality, surgical site infection, major peri-operative complications. There was no difference between the 2 groups in the Oxford knee score and quality of life index SF12 at 6-month follow-up. There was no difference in the range of knee flexion between the 2 groups at six months. Post-operative haemoglobin drop was significantly more in SS BLTKA patients and consequently, blood transfusion requirement was significantly higher in SS BLTKA. There was a significantly higher length of hospital stay and duration of surgery in TS BLTKA group. Conclusion There does not appear to be a difference in complication rates between the 2 groups. SS BLTKA seems to be a logical choice if both knees have severe osteoarthritis. Patients with severe cardiopulmonary compromise were excluded, and a unilateral procedure may be preferred in them.