An ankle foot orthosis that orients the ankle in slight dorsiflexion may help improve knee flexion during gait and reduce the risk of heel ulcers in post-stroke patients, according to research from Marquette University in Milwaukee.
Investigators performed gait analysis on eight patients with impaired mobility following a stroke, as they walked while wearing an experimental AFO set for three different ankle alignment conditions. The three AFO conditions (5° of plantar flexion, neutral, and 5° of dorsiflexion) were tested in random order.
While ambulating with the ankle in plantar flexion, subjects demonstrated significantly less knee flexion during the loading response phase of gait than when the ankle was in dorsiflexion. Six of the eight subjects also exhibited increased knee flexion moments during plantar flexion relative to dorsiflexion.
AFO alignment in plantar flexion was also associated with increased peak heel contact force during loading response, suggesting that this ankle orientation may be contraindicated in patients with a history of rearfoot ulcers.
The findings were e-published on March 29 by Prosthetics & Orthotics International.