RT Journal A1 Bhan, S. A1 Malhotra, R. A1 Kiran, E. Krishna A1 Shukla, Sourav A1 Bijjawara, Mahesh T1 A Comparison of Fixed-Bearing and Mobile-Bearing Total Knee Arthroplasty at a Minimum Follow-up of 4.5 Years JF The Journal of Bone & Joint Surgery JO The Journal of Bone & Joint Surgery YR 2005 FD October 1 VO 87 IS 10 SP 2290 OP 2296 DO 10.2106/JBJS.D.02221 UL http://dx.doi.org/10.2106/JBJS.D.02221 AB Background: Durable long-term independent results with the Low Contact Stress rotating-platform (mobile-bearing) and the Insall Burstein-II (fixed-bearing) total knee prostheses have been reported, but no studies describing either the mid-term or long-term results and comparing the two prostheses are available, to our knowledge.Methods: Thirty-two patients who had bilateral arthritis of the knee with similar deformity and preoperative range of motion on both sides and who agreed to have one knee replaced with a mobile-bearing total knee design and the other with a fixed-bearing design were prospectively evaluated. Comparative analysis of both designs was done at a mean follow-up period of six years, minimizing patient, surgeon, and observer-related bias. Clinical and radiographic outcome, survival, and complication rates were compared.Results: Patients with osteoarthritis had better function scores and range of motion compared with patients with rheumatoid arthritis. However, with the numbers available, no benefit of mobile-bearing over fixed-bearing designs could be demonstrated with respect to Knee Society scores, range of flexion, subject preference, or patellofemoral complication rates. Radiographs showed no difference in prosthetic alignment. Two knees with a mobile-bearing prosthesis required a reoperation: one had an early revision because of bearing dislocation and another required conversion to an arthrodesis to treat a deep infection.Conclusions: We found no advantage of the mobile-bearing arthroplasty over the fixed-bearing arthroplasty with regard to the clinical results at mid-term follow-up. The risk of bearing subluxation and dislocation in knees with the mobile-bearing prosthesis is a cause for concern and may necessitate early revision.Level of Evidence: Therapeutic Level II. See Instructions to Authors for a complete description of levels of evidence.