title: Prosthetic foot roll-over shapes with implications for alignment of trans-tibial prostheses.
abstract: Roll-over shape is introduced as a significant characteristic of prosthetic feet. The roll-over shapes of the Flexwalk, Quantum, SACH, and SAFE prosthetic feet were determined using three methods; two involving quasi-static loading and one dynamic loading. The results show that foot roll-over shape properties obtained by quasi-static and by dynamic methods are similar. Relationships between foot roll-over shape and the alignment of trans-tibial prostheses are introduced that suggest ways to align trans-tibial prostheses without walking trials and iterations. The relationships may explain what prosthetists attempt to accomplish when they dynamically align a trans-tibial limb. They also explain why prosthetic feet with different mechanical properties usually necessitate different alignments, and may explain why a number of gait studies of trans-tibial amputees do not show major gait differences when walking is executed on various kinds of prosthetic feet.
authors.affiliation: Department of Biomedical Engineering, Northwestern University, Chicago, IL, USA.
authors.forename: A H
authors.initials: AH
authors.lastname: Hansen
authors.forename: D S
authors.initials: DS
authors.lastname: Childress
authors.forename: E H
authors.initials: EH
authors.lastname: Knox
mesh_terms: D000671:Amputation, Surgical / Q000534:rehabilitation*; D001186:Artificial Limbs; D001696:Biomechanical Phenomena; D001698:Biomedical Engineering / Q000379:methods; D005528:Foot / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006801:Humans; D007866:Leg; D011474:Prosthesis Design; D017755:Prosthesis Fitting; D012680:Sensitivity and Specificity; D013977:Tibia / Q000601:surgery