Article

Lower extremity amputation not only limits mobility, but also increases the risk
of knee osteoarthritis of the intact limb. Dynamic walking models of non-amputees
suggest that pushing-off from the trailing limb can reduce collision forces on
the leading limb. These collision forces may determine the peak knee external
adduction moment (EAM), which has been linked to the development of knee OA in
the general population. We therefore hypothesized that greater prosthetic
push-off would lead to reduced loading and knee EAM of the intact limb in
unilateral transtibial amputees. Seven unilateral transtibial amputees were
studied during gait under three prosthetic foot conditions that were intended to
vary push-off. Prosthetic foot-ankle push-off work, intact limb knee EAM and
ground reaction impulses for both limbs during step-to-step transition were
measured. Overall, trailing limb prosthetic push-off work was negatively
correlated with leading intact limb 1st peak knee EAM (slope=-.72+/-.22; p=.011).
Prosthetic push-off work and 1st peak intact knee EAM varied significantly with
foot type. The prosthetic foot condition with the least push-off demonstrated the
largest knee EAM, which was reduced by 26% with the prosthetic foot producing the
most push-off. Trailing prosthetic limb push-off impulse was negatively
correlated with leading intact limb loading impulse (slope=-.34+/-.14; p=.001),
which may help explain how prosthetic limb push-off can affect intact limb
loading. Prosthetic feet that perform more prosthetic push-off appear to be
associated with a reduction in 1st peak intact knee EAM, and their use could
potentially reduce the risk and burden of knee osteoarthritis in this population.
CI - Published by Elsevier B.V.

Langue : ANGLAIS