title: Apparatus and methods for studying artificial feedback-control of the plantarflexors in paraplegics without interference from the brain.
abstract: Apparatus has been built to explore the practical feasibility of using automatic control with electrical stimulation of paralysed legs to restore function. The experiments are performed with paraplegics with the aim of achieving a realistic postural task: to see whether the body may be maintained upright by stimulation of the plantarflexors when the other joints are braced. Significantly, the intact upper body, under natural control of the brain, cannot interfere with the automatic control. The "Wobbler" apparatus allows measurement of the ankle muscle properties in isometric conditions or in sinusoidal motion. Using the biomechanical properties of the body, which are also measured, controllers for stabilising the body can be designed. Controllers can be dynamically tested, imitating anterior-posterior sway, while the body is held upright, before "actual standing" is attempted.
authors.affiliation: Department of Medical Physics and Bioengineering, University College London, UK.
authors.forename: N de N
authors.initials: Nde N
authors.lastname: Donaldson
authors.forename: M
authors.initials: M
authors.lastname: Munih
authors.forename: G F
authors.initials: GF
authors.lastname: Phillips
authors.forename: T A
authors.initials: TA
authors.lastname: Perkins
mesh_terms: D001696:Biomechanical Phenomena; D001915:Braces; D001921:Brain / Q000502:physiology; D004599:Electric Stimulation Therapy / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D005246:Feedback / Q000502:physiology; D005528:Foot; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D010264:Paraplegia / Q000503:physiopathology* / Q000628:therapy; D011187:Posture / Q000502:physiology; D012984:Software