Xavier Drevelle1, Coralie Villa2, Xavier Bonnet3, Isabelle Loiret4, Pascale Fodé5, Hélène Pillet6. 1. Institution Nationale des Invalides Centre d'Etude et de Recherche sur l'Appareillage des Handicapés, BP 50719, 57147 Woippy Cedex, France. Electronic address: xavier.drevelle@invalides.fr. 2. Arts et Metiers ParisTech, LBM, 151 boulevard de l'Hôpital, 75013 Paris, France. 3. PROTEOR, 6 rue de la redoute, 21250 Seurre, France. 4. Centre de médecine physique et de réadaptation Louis Pierquin IRR-UGECAM Nord-Est 75, Boulevard Lobau, CS 34209, 54042 Nancy Cedex, France. 5. Institution Nationale des Invalides Centre d'Etude et de Recherche sur l'Appareillage des Handicapés, BP 50719, 57147 Woippy Cedex, France. 6. Arts et Metiers ParisTech, LBM, 151 boulevard de l'Hôpital, 75013 Paris, France. Electronic address: helene.pillet@ensam.eu.
Abstract
BACKGROUND: Vaulting is a gait compensatory mechanism used by transfemoral amputees to assist toe clearance during the prosthetic swing phase. It is defined by a plantar flexion of the contralateral ankle during the single-limb support phase. The aim of the study is to propose a method to quantify vaulting of transfemoral amputees. METHODS: 17 transfemoral amputees and 28 asymptomatic subjects participated in the data collection. Kinematics and kinetics of the whole body were recorded while subjects were walking on a level surface. Biomechanical gait analysis was focused on a reduced set of parameters linked to the contralateral ankle, the contralateral knee and the trajectory of the center of pressure. The patients were classified in two groups: with or without vaulting using video recordings. Differences between both groups and the control group were analyzed. FINDINGS: A higher generated ankle power was found during the single support phase of the contralateral limb of transfemoral amputees presenting vaulting. These subjects presented also a higher dissipated knee flexion power before the peak in ankle flexion power. The trajectory of the center of pressure was also modified by the vaulting. INTERPRETATION: Vaulting for transfemoral amputees is characterized by a propulsive plantar flexion at the contralateral ankle. Quantifying the ankle flexion power during the contralateral single support phase will help in understanding vaulting.
BACKGROUND: Vaulting is a gait compensatory mechanism used by transfemoral amputees to assist toe clearance during the prosthetic swing phase. It is defined by a plantar flexion of the contralateral ankle during the single-limb support phase. The aim of the study is to propose a method to quantify vaulting of transfemoral amputees. METHODS: 17 transfemoral amputees and 28 asymptomatic subjects participated in the data collection. Kinematics and kinetics of the whole body were recorded while subjects were walking on a level surface. Biomechanical gait analysis was focused on a reduced set of parameters linked to the contralateral ankle, the contralateral knee and the trajectory of the center of pressure. The patients were classified in two groups: with or without vaulting using video recordings. Differences between both groups and the control group were analyzed. FINDINGS: A higher generated ankle power was found during the single support phase of the contralateral limb of transfemoral amputees presenting vaulting. These subjects presented also a higher dissipated knee flexion power before the peak in ankle flexion power. The trajectory of the center of pressure was also modified by the vaulting. INTERPRETATION: Vaulting for transfemoral amputees is characterized by a propulsive plantar flexion at the contralateral ankle. Quantifying the ankle flexion power during the contralateral single support phase will help in understanding vaulting.