A Portable Powered Ankle-Foot Orthosis for RehabilitationBy Shorter, K. Alex; Kogler, Geza F.; Loth, Eric; Durfee, William K.; Hsiao-Wecksler, Elizabeth T.; Journal of Rehabilitation Research and Development, Vol. 48, No. 4, pp. 459-472
Publication Date: 2011
Article presents a novel portable powered ankle-foot orthosis (PPAFO) to provide untethered assistance for daily in-home rehabilitation treatment. The PPAFO provides both plantar flexor and dorsiflexor torque assistance by way of a bidirectional pneumatic rotary actuator. The system uses a portable pneumatic power source and embedded electronics to control the actuation of the foot. The power source is a commercially available compressed liquid carbon dioxide bottle with a pressure regulator. To demonstrate design functionality, the PPAFO was tested during treadmill walking with 3 nondisabled male participants with a mean age of 26 years and a 51-year-old male participant with bilateral impairment of the lower legs due to Cauda Equina Syndrome. Data from nondisabled participants demonstrated the PPAFO’s capability to provide correctly timed plantar flexor and dorsiflexor assistance during gait. Reduced activation of the tibialis anterior during stance and swing was also seen during assisted nondisabled walking trials. An increase in the vertical ground reaction force during the second half of stance was present during assisted trials for the impaired participant. Data from the nondisabled walkers demonstrated functionality, and data from the participant with lower leg impairment demonstrated the ability to provide functional plantar flexor assistance. Implications for future studies with the PPAFO using larger participant populations are discussed.
VA Rehabilitation Research & Development Service (Web Site: http://www.rehab.research.va.gov )
Link to text: http://www.rehab.research.va.gov/jour/11/484/shorter484.html
This publication is included in the library of the National Rehabilitation Information Center (NARIC), accession number J61383