title: Deviations From Optimal Alignment in TKA: Is There a Biomechanical Difference Between Femoral or Tibial Component Alignment?
abstract: Restoration of neutral mechanical alignment is one of the prerequisites for long-term TKA survival. This study aimed to investigate the effect of deviations from neutral alignment on bone and implant stress and on ligament strain. Using a previously validated finite element model, a neutrally aligned TKA model was compared to 3 different varus and valgus configurations induced by tibial or by femoral component only and by both component simultaneously. Each model underwent a 2500 N vertical load simulating the peak walking force. Varus and valgus alignment increased polyethylene and bone stress, and altered ligament strains, as compared to the neutral aligned model. Changes in alignment of the tibial component were always associated with more detrimental effects compared to the one of the femoral component.
authors: BEAMS Department, Université Libre de Bruxelles, Brussels, Belgium.
authors: Bernardo
authors: B
authors: Innocenti
authors: Department of Orthopedic Surgery, Ziekenhuis Oost-Limburg, Genk, Belgium.
authors: Johan
authors: J
authors: Bellemans
authors: Orthopaedics and Traumatology Department, Modena Policlinic, Modena, Italy.
authors: Fabio
authors: F
authors: Catani
mesh_terms: D019645:Arthroplasty, Replacement, Knee; D001696:Biomechanical Phenomena; D005269:Femur / Q000601:surgery*; D020342:Finite Element Analysis; D006801:Humans; D020959:Polyethylene / Q000737:chemistry*; D016062:Porosity; D011474:Prosthesis Design; D013314:Stress, Mechanical; D013977:Tibia / Q000601:surgery*; D016138:Walking
chemical_list: D020959:Polyethylene
keywords: TKA; collateral ligament strain; neutral mechanical alignment; tibial stress; valgus alignment; varus alignment