title: Intraoperative passive knee kinematics during total knee arthroplasty surgery.
abstract: Surgical navigation systems for total knee arthroplasty (TKA) surgery are capable of capturing passive three-dimensional (3D) angular joint movement patterns intraoperatively. Improved understanding of patient-specific knee kinematic changes between pre and post-implant states and their relationship with post-operative function may be important in optimizing TKA outcomes. However, a comprehensive characterization of the variability among patients has yet to be investigated. The objective of this study was to characterize the variability within frontal plane joint movement patterns intraoperatively during a passive knee flexion exercise. Three hundred and forty patients with severe knee osteoarthritis (OA) received a primary TKA using a navigation system. Passive kinematics were captured prior to (pre-implant), and after prosthesis insertion (post-implant). Principal component analysis (PCA) was used to capture characteristic patterns of knee angle kinematics among patients, to identify potential patient subgroups based on these patterns, and to examine the subgroup-specific changes in these patterns between pre- and post-implant states. The first four extracted patterns explained 99.9% of the diversity within the frontal plane angle patterns among the patients. Post-implant, the magnitude of the frontal plane angle shifted toward a neutral mechanical axis in all phenotypes, yet subtle pattern (shape of curvature) features of the pre-implant state persisted.
authors.affiliation: School of Biomedical Engineering, Dalhousie University, Dentistry Building, city, Halifax, NS, Canada, B3H 3J5.
authors.forename: Kathryn L
authors.initials: KL
authors.lastname: Young
authors.affiliation: School of Biomedical Engineering, Dalhousie University, Dentistry Building, city, Halifax, NS, Canada, B3H 3J5.|Department of Surgery, Dalhousie University, Halifax, NS, Canada.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Dunbar
authors.affiliation: Department of Surgery, Dalhousie University, Halifax, NS, Canada.
authors.forename: Glen
authors.initials: G
authors.lastname: Richardson
authors.affiliation: School of Biomedical Engineering, Dalhousie University, Dentistry Building, city, Halifax, NS, Canada, B3H 3J5.
authors.forename: Janie L
authors.initials: JL
authors.lastname: Astephen Wilson
mesh_terms: D019645:Arthroplasty, Replacement, Knee; D001696:Biomechanical Phenomena; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D025341:Principal Component Analysis; D012189:Retrospective Studies
keywords: computer-assisted surgery; knee kinematics; principal component analysis; surgical navigation; total knee arthroplasty