Article

Conventional prosthetic feet cannot adapt to specific conditions such as walking
on stairs or ramps. Amputees are therefore forced to compensate their prosthetic
deficits by modifying the kinematics and kinetics of their lower limbs. The
Proprio-Foot (Ossur) intends to reduce these compensation mechanisms by
automatically increasing dorsiflexion during stair ambulation thanks to an
adaptive microprocessor-controlled ankle. The present investigation proposes to
analyze the biomechanical effects of the dorsiflexion adaptation in transtibial
(TT) amputees during stair ambulation. Sixteen TT amputees and sixteen healthy
controls underwent conventional 3D gait analysis. Kinematics and kinetics of the
lower limbs were compared during stair ascent and descent performed by patients
with the prosthetic foot set to a neutral ankle angle and with an adapted
dorsiflexion ankle angle of 4 degrees . Norm distance as well as minimum and
maximal values of sagittal kinematics and kinetics were calculated for
comparisons between patients and control subjects. For both stair ascent and
descent, an improvement of the knee kinematics and kinetics could particularly be
noticed on the involved side with an increase of the knee flexion and an increase
of the knee moment during stance. Therefore, despite its additional weight
compared to a conventional prosthetic ankle, the Proprio-Foot should be
beneficial to active TT amputees whose knee musculature strength does not
constitute a handicap.

Langue : ANGLAIS