Impact de l'arthrose au genou sur les articulations de la hanche et de la cheville en se basant sur une analyse biomécanique

Abstract

Numerous studies use biomechanical data to investigate pathologies such as knee osteoarthritis. The classification of knee osteoarthritis (OA) vs. asymptomatic (AS) subjects has already been made using knee kinematics during gait. However, the consequences of osteoarthritis on other joints of the lower limb are poorly documented. The objective of this project is to analyze the impact of knee osteoarthritis on hip and ankle during gait : 3D angular kinematics patterns of the three joints are analyzed for OA and AS populations and used to classify subjects. The biomechanical data was obtained during a gait analysis protocol from a previous project. The latter was conducted on 15 asymptomatic subjects and 32 knee osteoarthritis patients. (1) Statistical analysis is performed on kinematic curves of each joint expressed in each anatomical plane during a gait cycle. Analysis of variance (ANOVA) was calculated for each percent of the gait cycle and on points of interest. This was used to compare means between groups and identify local parameters allowing distinguishing between groups. The significance level was set at p = 0.05. (2) The classification system used is based on the method of subspaces and uses the singular value decomposition (SVD). This global approach allows characterizing the signals in their totality while also identifying gait sub-cycles that allow a better discrimination between groups. Knee osteoarthritis patients show increased abduction in the hip movement during the stance phase, and less in external rotation than controls, especially at pre-swing (2.0°, p = 0.01). During the stance phase, knee flexion of osteoarthritic patients is lower (4.7°, p = 0.003) and remains in decreased internal tibial rotation compared to asymptomatics (1.0°, p = 0.01). Finally, the ankle is less in eversion during swing and more in plantar flexion along the entire cycle. The classification gives excellent results for knee kinematics, with more than 95% of subjects correctly classified in the frontal plane, but also very good rates at hip and ankle, respectively up to 89% and 85% in the sagittal plane. The swing phase reveals the best rates in sagittal plane at the three joints. Gait 3D kinematic patterns of OA patients reveal significant differences with those of AS subjects at the three joints of lower limb. The presence of knee osteoarthritis leads to adjustment of angular displacements strategies of knee, but also of hip and ankle. In addition, both groups can be classified according to rotations recorded at the three joints, opening the way for further research to identify coping strategies of locomotor system against disease and predict its development using strengthened classification systems.

Date	10 May 2012
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Neila Mezghani (Supervisor) & Nicola Hagemeister (Co-supervisor)