Key Outcomes:
Gait Speed: The 3 studies that looked at long-term PN FES showed increases ranging from a 13% to a 55% change at 12 months.
The results of all the PN FES studies for this population demonstrate increased gait speed regardless of whether the gait was tested over-ground with PN FES or with PN FES and BWSTT. The study comparing the short-term efficacy of PN FES to AFOs measured over-ground gait speed under three conditions: AFO alone, PN FES alone and with both devices combined, reporting a 10% increase in gait speed with PN FES alone and an 18% increase when PN FES was combined with an AFO. The 3 studies that looked at long-term PN FES showed increases ranging from a 13% to a 55% change at 12 months. One of these studies also looked at possible therapeutic effects, or the continued improvement noted when device is turned off, and found that at 12 months the subjects with SCI showed a 28% increase in gait speed without PN FES.
Four of the therapeutic studies measured changes in gait speed with PN FES both over-ground and with BWSTT and showed very significant increases. The duration of PN FES in these studies varied from sessions lasting 60 minutes 3 days/week for 12 weeks to sessions lasting 60 minutes 5 times/day for 12 weeks. The results of these studies showed large increases in gait speed ranging from a 55%1 to an 84% increase. Two of the studies reported remarkable increases of 6% and 8% respectively when the subjects walked with PN FES and BWSTT. Additionally, one study reported that of all the training methods, the most significant gait speed gains occurred in the over-ground with PN FES group. This study showed that the PN FES over-ground group had the most significant gains in distance walked during the 2 minute walk test as well.
Gait Symmetry:
Two of the studies that compared PN FES over-ground and with BWSTT reported increases in step and stride length with one also reporting an increase in the symmetry of swing and stance phase.
Other outcomes: In the study comparing PN FES and AFOs under three conditions: AFO, PN FES and a combination of both devices, results showed that the distance between the subject’s foot and the floor during swing was significantly greater with PN FES than with an AFO. The combination of AFO and PN FES was even more effective for foot clearance. Considering that the AFO is currently the standard of care for reducing foot drop; it is significant that this study shows PN FES to be superior to bracing in that regard.
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