Research Article Kinematics of the Normal Knee during Dynamic Activities: A Synthesis of Data from Intracortical Pins and Biplane Imaging Xavier Gasparutto, 1 Florent Moissenet, 2 Yoann Lafon, 1 Laurence Chèze, 1 and Raphaël Dumas 1 1 University Lyon, Université Claude Bernard Lyon 1, IFSTTAR, LBMC UMR_T9406, 69622 Lyon, France 2 Centre National de Rééducation Fonctionnelle et de Réadaptation-Rehazenter, Laboratoire d’Analyse du Mouvement et de la Posture (LAMP), Luxembourg, Luxembourg Correspondence should be addressed to Raphaël Dumas; raphael.dumas@ifsttar.fr Received 16 November 2016; Revised 9 January 2017; Accepted 29 January 2017; Published 11 April 2017 Academic Editor: Luis Gracia Copyright © 2017 Xavier Gasparutto et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Few studies have provided in vivo tibiofemoral kinematics of the normal knee during dynamic weight-bearing activities. Indeed, gold standard measurement methods (i.e., intracortical pins and biplane imaging) raise ethical and experimental issues. Moreover, the conventions used for the processing of the kinematics show large inconsistencies. This study aims at synthesising the tibiofemoral kinematics measured with gold standard measurement methods. Published kinematic data were transformed in the standard recommended by the International Society of Biomechanics (ISB), and a clustering method was applied to investigate whether the couplings between the degrees of freedom (DoFs) are consistent among the different activities and measurement methods. The synthesised couplings between the DoFs during knee flexion (from 4 ° of extension to -61 ° of flexion) included abduction (up to -10 ° ); internal rotation (up to 15 ° ); and medial (up to 10 mm), anterior (up to 25 mm), and proximal (up to 28 mm) displacements. These synthesised couplings appeared mainly partitioned into two clusters that featured all the dynamic weight-bearing activities and all the measurement methods. Thus, the effect of the dynamic activities on the couplings between the tibiofemoral DoFs appeared to be limited. The synthesised data might be used as a reference of normal in vivo knee kinematics for prosthetic and orthotic design and for knee biomechanical model development and validation. 1. Introduction Due to ethical and experimental issues, very few studies have provided the in vivo tibiofemoral kinematics of the normal knee. Indeed, the only methods that can accurately provide such information are intracortical pins coupled with the Roentgen stereophotogrammetric analysis of the bones (e.g., [1]), biplane fluoroscopy coupled with computed tomography and three-dimensional (3D) reconstruction of the bones (e.g., [2]), and high-speed stereoradiography with bone-implanted radio-opaque markers (e.g., [3]). These methods are considered the gold standard but are invasive and/or ionising. The present study aimed at getting a better understanding of the healthy knee in vivo tibiofemoral kinematics during dynamic activities. Indeed, knowledge of the normal in vivo tibiofemoral kinematics is essential to evaluate pathological conditions and surgical treatments or to design knee pros- thesis and orthosis that are consistent with a healthy knee. A synthesis of data from intracortical pins and biplane imaging was proposed. Rather than a systematic review, which would have only revealed the inconsistency of the reported data, a reprocessing of the 6 degrees of freedom (DoFs) of the tibiofemoral joint using a standardised method was performed based on mean curves displayed in the published papers. Indeed, various conventions have been used in literature to report the kinematic data of the knee, resulting in contradictory observations and inability to compare data, even if conformation to the general method of Grood and Suntay [4] was most commonly claimed. Thus, to allow the comparison between datasets with different conventions, the kinematics displayed in studies that used intracortical pins and biplane imaging were transformed into the standardised convention proposed Hindawi Applied Bionics and Biomechanics Volume 2017, Article ID 1908618, 9 pages https://doi.org/10.1155/2017/1908618