title: Static ankle impedance in stroke and multiple sclerosis: a feasibility study.
abstract: Quantitative characterization of ankle mechanical impedance is critical for understanding lower extremity function in persons with neurological disorders. In this paper, we examine the feasibility of employing an ankle robot and multivariable analysis to determine static ankle impedance in 4 patients: 1 with multiple sclerosis and 3 with stroke. We employed a scalar based vector field approximation method which was successful in identifying young healthy subjects' ankle impedance. It enabled clear interpretation of spatial ankle impedance structure and intermuscular feedback at the ankle for both affected and unaffected legs. Measured impedance of two patients was comparable to healthy young subjects, while the other two patients had significantly different static ankle impedance properties.
authors.affiliation: Mechanical Engineering Department, Massachusetts Institute of Technology, MA 02139, USA. hyunglae@mit.edu
authors.forename: Hyunglae
authors.initials: H
authors.lastname: Lee
authors.forename: Tara
authors.initials: T
authors.lastname: Patterson
authors.forename: Jooeun
authors.initials: J
authors.lastname: Ahn
authors.forename: Daniel
authors.initials: D
authors.lastname: Klenk
authors.forename: Albert
authors.initials: A
authors.lastname: Lo
authors.forename: Hermano Igo
authors.initials: HI
authors.lastname: Krebs
authors.forename: Neville
authors.initials: N
authors.lastname: Hogan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000842:Ankle / Q000503:physiopathology*; D016022:Case-Control Studies; D017097:Electric Impedance; D005240:Feasibility Studies; D005260:Female; D006262:Health; D006801:Humans; D007595:Joint Prosthesis; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000503:physiopathology* / Q000534:rehabilitation; D012371:Robotics / Q000295:instrumentation*; D012399:Rotation; D020521:Stroke / Q000503:physiopathology*; D000071939:Stroke Rehabilitation; D055815:Young Adult