title: Tibio-femoral joint contact in healthy and osteoarthritic knees during quasi-static squat: A bi-planar X-ray analysis.
abstract: The aim of this study was to quantify the tibio-femoral contact point (CP) locations in healthy and osteoarthritic (OA) subjects during a weight-bearing squat using stand-alone biplanar X-ray images. Ten healthy and 9 severe OA subjects performed quasi-static squats. Bi-planar X-ray images were recorded at 0°, 15°, 30°, 45°, and 70° of knee flexion. A reconstruction/registration process was used to create 3D models of tibia, fibula, and femur from bi-planar X-rays and to measure their positions at each posture. A weighted centroid of proximity algorithm was used to calculate the tibio-femoral CP locations. The accuracy of the reconstruction/registration process in measuring the quasi-static kinematics and the contact parameters was evaluated in a validation study. The quasi-static kinematics data revealed that in OA knees, adduction angles were greater (p<0.01), and the femur was located more medially relative to the tibia (p<0.01). Similarly, the average CP locations on the medial and lateral tibial plateaus of the OA patients were shifted (6.5±0.7mm; p<0.01) and (9.6±3.1mm; p<0.01) medially compared to the healthy group. From 0° to 70° flexion, CPs moved 8.1±5.3mm and 8.9±5.3mm posteriorly on the medial and lateral plateaus of healthy knees; while in OA joints CPs moved 10.1±8.4mm and 3.6±2.8mm posteriorly. The average minimum tibio-femoral bone-to-bone distances of the OA joints were lower in both compartments (p<0.01). The CPs in the OA joints were located more medially and displayed a higher ratio of medial to lateral posterior translations compared to healthy joints.
authors.affiliation: Laboratoire de Recherche en Imagerie et Orthopédie (LIO), École de Technologie Supérieure (ÉTS), Centre de Recherche du CHUM, Montréal, Québec, Canada. Electronic address: zeighamiali87@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: Zeighami
authors.affiliation: Univ Lyon, Université Claude Bernard Lyon 1, IFSTTAR, UMR_T9406, LBMC, F69622 Lyon, France. Electronic address: raphael.dumas@ifsttar.fr.
authors.forename: R
authors.initials: R
authors.lastname: Dumas
authors.affiliation: Laboratoire de Recherche en Imagerie et Orthopédie (LIO), École de Technologie Supérieure (ÉTS), Centre de Recherche du CHUM, Montréal, Québec, Canada. Electronic address: michele.kanhonou@gmail.com.
authors.forename: M
authors.initials: M
authors.lastname: Kanhonou
authors.affiliation: Laboratoire de Recherche en Imagerie et Orthopédie (LIO), École de Technologie Supérieure (ÉTS), Centre de Recherche du CHUM, Montréal, Québec, Canada. Electronic address: Nicola.Hagemeister@etsmtl.ca.
authors.forename: N
authors.initials: N
authors.lastname: Hagemeister
authors.affiliation: Department of Orthopedic Surgery, Centre Hospitalier de l׳Université de Montréal (CHUM), Montréal, Québec, Canada. Electronic address: fredericlavoiemd@gmail.com.
authors.forename: F
authors.initials: F
authors.lastname: Lavoie
authors.affiliation: Laboratoire de Recherche en Imagerie et Orthopédie (LIO), École de Technologie Supérieure (ÉTS), Centre de Recherche du CHUM, Montréal, Québec, Canada. Electronic address: jacques.deguise@etsmtl.ca.
authors.forename: J A
authors.initials: JA
authors.lastname: de Guise
authors.affiliation: Laboratoire de Recherche en Imagerie et Orthopédie (LIO), École de Technologie Supérieure (ÉTS), Centre de Recherche du CHUM, Montréal, Québec, Canada. Electronic address: Rachid.Aissaoui@etsmtl.ca.
authors.forename: R
authors.initials: R
authors.lastname: Aissaoui
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001696:Biomechanical Phenomena; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011187:Posture / Q000502:physiology*; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology; D013977:Tibia / Q000000981:diagnostic imaging / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology
keywords: Bi-planar X-ray; In vivo tibio-femoral contact; Knee quasi-static kinematics; Osteoarthritis; Squat