Neuroprosthesis for footdrop compared with an ankle-foot orthosis: effects on postural control during walking.
OBJECTIVE
We sought to compare the effects of a radio frequency-controlled neuroprosthesis on gait stability and symmetry to the effects obtained with a standard ankle-foot orthosis (AFO).


METHODS
A total of 15 patients (mean age: 52.2 +/- 3.6 years) with prior chronic hemiparesis resulting from stroke or traumatic brain injury (5.9 +/- 1.5 year) whose walking was impaired by footdrop and regularly used an AFO participated in the study. There was a 4-week adaptation period during which participants increased their daily use of the neuroprosthesis, while using the AFO for the rest of the day. Gait was then assessed in a 6-minute walk while wearing force-sensitive insoles, by using the neuroprosthesis and the AFO in a randomized order. An additional gait assessment was conducted after using the neuroprosthesis for a further 4 weeks. Gait speed and stride time (inverse of cadence) were determined, as were gait asymmetry index and swing time variability.


RESULTS
After the 4-week adaptation period, there were no differences between walking with the neuroprosthesis and walking with the AFO (P > .05). After 8 weeks, there was no significant difference in gait speed, whereas stride time improved from 1.48 +/- 0.21 seconds with the AFO to 1.41 +/- 0.16 seconds with the neuroprosthesis (P < .02). Swing time variability decreased from 5.3 +/- 1.6% with the AFO to 4.3 +/- 1.4% with the neuroprosthesis (P = .01). A gait asymmetry index improved by 15%, from 0.20 +/- 0.09 with the AFO to 0.17 +/- 0.08 with the neuroprosthesis (P < .05).


CONCLUSIONS
Compared with AFO, the studied neuroprosthesis appears to enhance balance control during walking and, thus, more effectively manage footdrop.
Ring
Haim
H
Neurological Rehabilitation Department, Loewenstein Rehabilitation Center, Ranana, Israel.
Treger
Iuly
I
Gruendlinger
Leor
L
Hausdorff
Jeffrey M
JM
D000222:Adaptation, Physiological; D001186:Artificial Limbs; D001696:Biomechanical Phenomena; D001900:Boston; D001930:Brain Injuries / Q000150:complications* / Q000503:physiopathology / Q000534:rehabilitation; D004599:Electric Stimulation Therapy; D004867:Equipment Design; D005260:Female; D020233:Gait Disorders, Neurologic / Q000209:etiology / Q000503:physiopathology / Q000534:rehabilitation*; D006801:Humans; D007557:Israel; D008297:Male; D008875:Middle Aged; D009989:Orthotic Devices; D017060:Patient Satisfaction; D010465:Perception; D010543:Peroneal Nerve / Q000503:physiopathology; D004856:Postural Balance; D011474:Prosthesis Design; D020127:Recovery of Function; D020521:Stroke / Q000150:complications* / Q000503:physiopathology; D000071939:Stroke Rehabilitation; D016896:Treatment Outcome; D016138:Walking