title: Intelligent stretching of ankle joints with contracture/spasticity.
abstract: An intelligent stretching device was developed to treat the spastic/contractured ankle of neurologically impaired patients. The device stretched the ankle safely throughout the range of motion (ROM) to extreme dorsiflexion and plantarflexion until a specified peak resistance torque was reached with the stretching velocity controlled based on the resistance torque. The ankle was held at the extreme position for a period of time to let stress relaxation occur before it was rotated back to the other extreme position. Stretching was slow at the joint extreme positions, making it possible to reach a larger ROM safely and it was fast in the middle ROM so the majority of the treatment was spent in stretching the problematic extreme ROM. Furthermore, the device evaluated treatment outcome quantitatively in multiple aspects, including active and passive ROM, joint stiffness and viscous damping and reflex excitability. The stretching resulted in considerable changes in joint passive ROM, stiffness, viscous damping and reflex gain. The intelligent control and yet simple design of the device suggest that with appropriate simplification, the device can be made portable and low cost, making it available to patients and therapists for frequent use in clinics/home and allowing more effective treatment and long-term improvement.
authors.affiliation: Rehabilitation Institute of Chicago, the Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, IL 60611 USA. l-zhang@northwestern.edu
authors.forename: Li-Qun
authors.initials: LQ
authors.lastname: Zhang
authors.forename: Sun G
authors.initials: SG
authors.lastname: Chung
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Bai
authors.forename: Dali
authors.initials: D
authors.lastname: Xu
authors.forename: Elton M T
authors.initials: EM
authors.lastname: van Rey
authors.forename: Mark W
authors.initials: MW
authors.lastname: Rogers
authors.forename: Marjorie E
authors.initials: ME
authors.lastname: Johnson
authors.forename: Elliot J
authors.initials: EJ
authors.lastname: Roth
mesh_terms: D000328:Adult; D000843:Ankle Joint / Q000503:physiopathology*; D001185:Artificial Intelligence; D003286:Contracture / Q000209:etiology / Q000534:rehabilitation*; D004548:Elasticity; D004867:Equipment Design; D005240:Feasibility Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015915:Motion Therapy, Continuous Passive / Q000295:instrumentation* / Q000379:methods*; D009128:Muscle Spasticity / Q000209:etiology / Q000534:rehabilitation*; D016059:Range of Motion, Articular; D012026:Reflex, Stretch; D012399:Rotation; D012680:Sensitivity and Specificity; D020521:Stroke / Q000150:complications; D019415:Torque; D016896:Treatment Outcome; D014783:Viscosity