title: Comparing a passive-elastic and a powered prosthesis in transtibial amputees.
abstract: Passive-elastic foot prostheses cannot produce net work. Consequently, passive-elastic foot prostheses are limited in their ability to enable a biologically-realistic gait pattern in transtibial amputees. This shortcoming results in difficulties in balance and walking and leads to high levels of oxygen consumption during locomotion. A powered prosthesis has the potential for overcoming these problems and allowing transtibial amputees to achieve a biologically-realistic gait pattern. In this study, we compared the effects of the Ceterus by Össur, a traditional passive-elastic prosthesis, with those of the PowerFoot Biom (iWalk, Cambridge, MA), a recently-developed powered prosthesis. Gait biomechanics and metabolic cost were compared in a group of 5 transtibial amputees during level-ground walking. The results provided preliminary evidence that the use of a powered prosthesis leads to a decrease in the level of oxygen consumption during ambulation due to improvements in ankle kinematics and kinetics primarily during late stance. An average decrease in oxygen consumption of 8.4% was observed during the study when subjects used the PowerFoot compared to the Ceterus. An average increase of 54% was observed in the peak ankle power generation during late stance. Our results suggest that powered prostheses have the potential for significantly improving ambulation in transtibial amputees.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Harvard Medical School, Spaulding Rehabilitation Hospital,Boston, MA 02114, USA. cmancinelli@partners.org
authors.forename: Chiara
authors.initials: C
authors.lastname: Mancinelli
authors.forename: Benjamin L
authors.initials: BL
authors.lastname: Patritti
authors.forename: Peppino
authors.initials: P
authors.lastname: Tropea
authors.forename: Richard M
authors.initials: RM
authors.lastname: Greenwald
authors.forename: Rick
authors.initials: R
authors.lastname: Casler
authors.forename: Hugh
authors.initials: H
authors.lastname: Herr
authors.forename: Paolo
authors.initials: P
authors.lastname: Bonato
mesh_terms: D000328:Adult; D000674:Amputees; D001186:Artificial Limbs; D001696:Biomechanical Phenomena; D004548:Elasticity; D004560:Electricity; D006801:Humans; D007700:Kinetics; D008297:Male; D010101:Oxygen Consumption; D013977:Tibia / Q000601:surgery*