Staged bilateral mobile-bearing and fixed-bearing total knee arthroplasty in the same patients: a prospective comparison of a posterior-stabilized prosthesis

Abstract

Mobile-bearing total knee arthroplasty (TKA) has several theoretical advantages over fixed-bearing TKA. We conducted a prospective randomized trial to compare the results of mobile-bearing and fixed-bearing posterior-stabilized TKA in the same patients using the same femoral component design of a mobile-bearing prosthesis in one knee and a fixed-bearing prosthesis in the other knee in 25 patients with osteoarthritis. The mean follow-up was 40 months. No significant differences were found in the mobile-bearing and fixed-bearing knees in terms of clinical and radiographic results. No osteolysis, loosening, or revision occurred. One knee with a mobile-bearing prosthesis had a dislocation of the rotating bearing; however, spontaneous reduction occurred and the dislocation did not recur. Satisfactory early results can be achieved in both mobile-bearing and fixed-bearing knees. We could not demonstrate an advantage of a mobile-bearing TKA.

Gait analysis of fixed bearing and mobile bearing total knee prostheses during walking: Do mobile bearings offer functional advantages?

“…In total knee replacement (TKR) surgery, mobile bearing (MB) prostheses facilitate planar rotation about the vertical axis of the tibia [1] and [2], with a view to reducing sub-surface stress through dual surface articulation at both the superior and inferior surfaces of a polyethylene insert [3] and [4]. Dual surface articulation promotes load sharing between the relative displacements of the tibial and femoral components, dissipating knee moments and shear forces to the surrounding soft tissues in a similar manner to the normal knee [5].…”

International Comparative Evaluation of Knee Replacement with Fixed or Mobile-Bearing Posterior-Stabilized Prostheses

“…Very few studies have specifically compared fixed-bearing posterior-stabilized and mobile-bearing posterior-stabilized total knee prostheses. In a small number of studies, no differences in midterm functional and radiographic outcomes between patients with fixed and those with mobile-bearing posteriorstabilized prostheses were identified 4,11,12 . In one study with limited follow-up, implant survival rates were also reported to be similar 14 .…”

“…Mobile bearings were introduced in an attempt to reduce polyethylene wear and possibly reduce torque at the bone-implant interface. In biomechanical testing, mobile bearings were found to reduce both contact stress and polyethylene wear; this has the potential to decrease the risk of revision, particularly in younger and more active patients [3][4][5][6][7] . It has also been argued that mobile bearings have the potential to enhance patellar tracking, reduce pain, enhance function, and reduce patellofemoral-related revision 8 .…”

“…It has also been argued that mobile bearings have the potential to enhance patellar tracking, reduce pain, enhance function, and reduce patellofemoral-related revision 8 . Many studies have compared clinical and radiographic outcomes of mobile and fixed-bearing total knee prostheses 4,5,7,[9][10][11][12] . One meta-analysis demonstrated an early reduction in anterior knee pain for patients with mobile-bearing total knee prostheses 7 .…”

Patellar Clunk Syndrome in Fixed-Bearing Posterior-Stabilised versus Cruciate-Substituting Prostheses

“…Studies of bilateral TKR with different prostheses in the same patient have compared mobile versus fixed-bearing models, [2][3][4] standard versus highflex models, 5 and standard versus gender-specific models. 6 Patellar clunk syndrome has been reported in different models, especially in posterior-stabilised prostheses.…”