Asymmetric polyethylene inserts promote favorable kinematics and better clinical outcome compared to symmetric inserts in a mobile bearing total knee arthroplasty

PurposeThis study aims at comparing the effects of symmetric and asymmetric designs for the polyethylene insert currently available and also for mobile bearing total knee arthroplasty (TKA). The investigation was performed both clinically and biomechanically through finite element analysis.Methods303 patients, with a mobile bearing TKA, were analyzed retrospectively. All patients received the same femoral and tibial components; for the insert, 151 patients received a symmetric design (SD) and 152 an asymmetric design (AD). Additionally, a 3D finite element model of a lower leg was developed, resurfaced with the same TKAs and analysed during gait and squat activities. TKA kinematics, and bone-stresses were investigated for the two insert solutions.ResultsAfter surgery, patients’ average flexion improved from 105°, with 5° of preoperative extension deficit, to 120° (AD-group) and 115° (SD-group) at the latest follow-up. There was no postoperative extension deficit. No pain affected the AD-group, while an antero-lateral pain was reported in some patients of the SD-group. Patients of the AD-group presented a better ability to perform certain physical routines. Biomechanically, the SD induced higher tibial-bone stresses than the AD. Both designs replicated similar kinematics, comparable to literature. However, SD rotates more on the tray, reducing the motion between femoral and polyethylene components, while AD permits greater insert rotation.ConclusionThe biomechanical analysis justifies the clinical findings. TKA kinematics is similar for the two designs, although the asymmetric solution shows less bone stress, thus resulting as more suitable to be cemented, avoiding lift-off issues, inducing less pain. Clinically, and biomechanically, an asymmetric mobile bearing insert could be a valid alternative to symmetric mobile bearing insert.Level of evidenceCase–control study retrospective comparative study, III.

[1]  Edgar Erdfelder,et al.  G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences , 2007, Behavior research methods.

[2]  Bernardo Innocenti,et al.  Tibio-femoral kinematics in different total knee arthroplasty designs during a loaded squat: a numerical sensitivity study. , 2012, Journal of biomechanics.

[3]  N. Mahomed,et al.  Meta-analysis and systematic review of clinical outcomes comparing mobile bearing and fixed bearing total knee arthroplasty. , 2011, The Journal of arthroplasty.

[4]  F. Catani,et al.  Load sharing and ligament strains in balanced, overstuffed and understuffed UKA. A validated finite element analysis. , 2014, The Journal of arthroplasty.

[5]  Johan Bellemans,et al.  The influence of muscle load on tibiofemoral knee kinematics , 2009, Journal of Orthopaedic Research.

[6]  Y. Jung,et al.  Comparison of the Clinical Outcomes after Total Knee Arthroplasty with the LCS Rotating Platform Mobile Bearing Knee System and the PFC Sigma RP-F Mobile Bearing Knee System , 2012, Clinics in orthopedic surgery.

[7]  Oguz Kayabasi,et al.  The effects of static, dynamic and fatigue behavior on three-dimensional shape optimization of hip prosthesis by finite element method , 2007 .

[8]  B. Innocenti,et al.  Biomechanical Effects of Different Varus and Valgus Alignments in Medial Unicompartmental Knee Arthroplasty. , 2016, The Journal of arthroplasty.

[9]  Ying Huang,et al.  A meta-analysis of the fixed-bearing and mobile-bearing prostheses in total knee arthroplasty , 2011, Archives of Orthopaedic and Trauma Surgery.

[10]  P Zioupos,et al.  Mechanical properties and the hierarchical structure of bone. , 1998, Medical engineering & physics.

[11]  J. Caillouette,et al.  Fat Embolism Syndrome Following the Intramedullary Alignment Guide in Total Knee Arthroplasty , 1990, Clinical orthopaedics and related research.

[12]  Johan Bellemans,et al.  Contact forces in several TKA designs during squatting: A numerical sensitivity analysis. , 2011, Journal of biomechanics.

[13]  B. Wroblewski,et al.  Reduction of postoperative blood loss after press-fit condylar knee arthroplasty with use of a femoral intramedullary plug. , 1993, The Journal of bone and joint surgery. American volume.

[14]  L Labey,et al.  Is there a biomechanical explanation for anterior knee pain in patients with patella alta?: influence of patellar height on patellofemoral contact force, contact area and contact pressure. , 2009, The Journal of bone and joint surgery. British volume.

[15]  A. Terrier,et al.  Effects of the posterior cruciate ligament reconstruction on the biomechanics of the knee joint: a finite element analysis. , 2005, Clinical biomechanics.

[16]  F. Catani,et al.  Deviations From Optimal Alignment in TKA: Is There a Biomechanical Difference Between Femoral or Tibial Component Alignment? , 2014, Journal of Arthroplasty.

[17]  Bernardo Innocenti,et al.  INVESTIGATION ON THE EFFECTS INDUCED BY TKA FEATURES ON TIBIO-FEMORAL MECHANICS PART II: TIBIAL INSERT DESIGNS , 2015 .

[18]  J. Victor,et al.  How precise can bony landmarks be determined on a CT scan of the knee? , 2009, The Knee.

[19]  P. Noble,et al.  The New Knee Society Knee Scoring System , 2012, Clinical orthopaedics and related research.

[20]  M. Hull,et al.  How the stiffness of meniscal attachments and meniscal material properties affect tibio-femoral contact pressure computed using a validated finite element model of the human knee joint. , 2003, Journal of biomechanics.

[21]  L. Labey,et al.  Stemmed TKA in a femur with a total hip arthroplasty: is there a safe distance between the stem tips? , 2013, The Journal of arthroplasty.

[22]  Héctor Robledo Yagüe,et al.  Investigation on the effects induced by TKA features on tibio-femoral mechanics part I: Femoral component designs , 2015 .

[23]  B P McNamara,et al.  Relationship between bone-prosthesis bonding and load transfer in total hip reconstruction. , 1997, Journal of biomechanics.

[24]  Claudio Belvedere,et al.  In vivo kinematics of knee replacement during daily living activities: Condylar and post‐cam contact assessment by three‐dimensional fluoroscopy and finite element analyses , 2017, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[25]  E. Erdfelder,et al.  Statistical power analyses using G*Power 3.1: Tests for correlation and regression analyses , 2009, Behavior research methods.

[26]  L. Vanlommel,et al.  Post-cam mechanics and tibiofemoral kinematics: a dynamic in vitro analysis of eight posterior-stabilized total knee designs , 2015, Knee Surgery, Sports Traumatology, Arthroscopy.

[27]  M Beaugonin,et al.  Simulation of a knee joint replacement during a gait cycle using explicit finite element analysis. , 2002, Journal of biomechanics.

[28]  Partha Sarathi Kopparti,et al.  Influence of three variables on the stresses in a three-dimensional model of a proximal tibia-total knee implant construct. , 2007, Bio-medical materials and engineering.

[29]  L. Labey,et al.  Knee kinetics and kinematics: What are the effects of TKA malconfigurations? , 2016, Knee Surgery, Sports Traumatology, Arthroscopy.

[30]  M. Ritter,et al.  "Thicker" polyethylene bearings are associated with higher failure rates in primary total knee arthroplasty. , 2010, The Journal of arthroplasty.

[31]  C. Hing,et al.  Clinical and radiological outcomes of fixed- versus mobile-bearing total knee replacement: a meta-analysis , 2010, Knee Surgery, Sports Traumatology, Arthroscopy.

[32]  L. Labey,et al.  All-polyethylene tibial components generate higher stress and micromotions than metal-backed tibial components in total knee arthroplasty , 2016, Knee Surgery, Sports Traumatology, Arthroscopy.

[33]  Colin D J Hopley,et al.  Long-term clinical outcomes and survivorship after total knee arthroplasty using a rotating platform knee prosthesis: a meta-analysis. , 2013, The Journal of arthroplasty.

[34]  A. Carr,et al.  Questionnaire on the perceptions of patients about total hip replacement. , 1996, The Journal of bone and joint surgery. British volume.

[35]  Miguel Ángel Martínez,et al.  A three-dimensional finite element analysis of the combined behavior of ligaments and menisci in the healthy human knee joint. , 2006, Journal of biomechanics.

[36]  W. Yau,et al.  Unusual complication associated with femoral intramedullary alignment guide in total knee arthroplasty. , 2001, The Journal of arthroplasty.

[37]  Jimmie Leppink,et al.  Effect size – large, medium, and small , 2016, Perspectives on medical education.

[38]  L. Labey,et al.  Fixation techniques and stem dimensions in hinged total knee arthroplasty: a finite element study , 2016, Archives of Orthopaedic and Trauma Surgery.

[39]  Bernardo Innocenti,et al.  A new graphical method to display data sets representing biomechanical knee behaviour , 2015, Journal of Experimental Orthopaedics.

[40]  A. Leardini,et al.  The Mark Coventry Award Articular: Contact Estimation in TKA Using In Vivo Kinematics and Finite Element Analysis , 2010, Clinical orthopaedics and related research.

[41]  K. Oh,et al.  Meta-analysis comparing outcomes of fixed-bearing and mobile-bearing prostheses in total knee arthroplasty. , 2009, The Journal of arthroplasty.

[42]  D. Dennis,et al.  Mobile-bearing total knee arthroplasty: a meta-analysis. , 2010, The Journal of arthroplasty.

[43]  S. Kurtz,et al.  International survey of primary and revision total knee replacement , 2011, International Orthopaedics.

[44]  C. Rimnac,et al.  Ultra high molecular weight polyethylene: mechanics, morphology, and clinical behavior. , 2009, Journal of the mechanical behavior of biomedical materials.

[45]  L Cristofolini,et al.  The 'standardized femur program' proposal for a reference geometry to be used for the creation of finite element models of the femur. , 1996, Journal of biomechanics.

[46]  J. Weiss,et al.  Subject‐specific finite element analysis of the human medial collateral ligament during valgus knee loading , 2003, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[47]  B. Innocenti,et al.  How accurate and reproducible are the identification of cruciate and collateral ligament insertions using MRI? , 2016, The Knee.

[48]  J. Bellemans,et al.  Can medio-lateral baseplate position and load sharing induce asymptomatic local bone resorption of the proximal tibia? A finite element study , 2009, Journal of orthopaedic surgery and research.

[49]  Lutz Dürselen,et al.  Material Models and Properties in the Finite Element Analysis of Knee Ligaments: A Literature Review , 2014, Front. Bioeng. Biotechnol..

[50]  Federica Verdini,et al.  Assessment of patient functional performance in different knee arthroplasty designs during unconstrained squat. , 2019, Muscles, ligaments and tendons journal.

[51]  Yulin Li,et al.  No difference in clinical outcome between fixed- and mobile-bearing TKA: a meta-analysis , 2014, Knee Surgery, Sports Traumatology, Arthroscopy.