Outcomes of Bilateral Simultaneous Primary Total Knee Arthroplasty with Tibial Stems or Revision Implants

Abstract Background: Total knee arthroplasty (TKA) is reported to be a successful means of relieving pain and restoring function in end-stage arthritis. Performing simultaneous bilateral TKA (simBTKA) has advantages such as a single anesthetic session, reduced cost, and better joint rehabilitation. This paper evaluates the outcomes of simBTKA using patient-specific templating (PST) in patients who had unilateral tibial stem or revision implants. Methods: After obtaining ethical approval and collecting informed consent, the data for this study were collected prospectively using the Egyptian community arthroplasty registry. We included 120 patients with severe bilateral osteoarthritis confirmed clinically and radiologically, accepted for simBTKA, and patients who only had their operations using PST. Exclusion criteria included unicompartmental replacement, revision knee replacement, and bilateral simultaneous knee replacement using a primary prosthesis with no stem. We compared the outcomes of the knee society score (KSS) and range of motion (ROM) between the two groups using Student’s- t -test. Results: Most patients were female (75%), and the mean age of all participants was 65.1 (standard deviation = 7.5) years. Although there was an age difference between the two groups ( P = 0.026), there were no other differences in the preoperative varus ( P = 0.085) and fixed flexion ( P = 0.185) deformities. No mortality was reported. The outcomes were comparable between the two groups regarding the improvement in KSS ( P = 0.711) and improvement in ROM ( P = 0.270). However, seven patients reported eight complications, with the most severe one being a superficial infection that required debridement and polyethylene exchange. Conclusion: Using tibial stems or revision implants in simBTKA offers the anticipated improvement in KSS and ROM. This adds to the advantages of simBTKA, especially with the use of PST or its commercial equivalent, patient-specific instrumentation.