The kinematics and kinetics of walking using a forefoot offloading shoe in patients with diabetes and periferal neuropathy.

Forefoot offloading shoes are frequently used as offloading device for
treatment of plantar forefoot ulcers in patients with diabetes. Earlier studies
have show the significant pressure-relieving effect of FOS when compare with a
standard shoe in this population (Bus et al., 2005). Due to the deviant sole
construction of the FOS, in which the roll-over process over the forefoot does
not take place, we believe that patient use a significantly different gait
pattern when walking in these shoes. This may lead to compensating strategies
that may result in complaints. Moreover, balance of walking, which is already
affected because of the sensory neuropathy, may be further affected through
these shoes which may increase the chance of falling incidents. Earlier
research has shown that patients have a significantly reduced walking comfort
in FOS. By measuring the lower-extremity dynamics of walking in diabetic
neuropathic patients while walking in FOS we may be able to understand the
mechanisms of forefoot pressure relief in these shoes. Moreover, it may be
possible to assess changes in the gait pattern that may lead to complaints,
falling incidents or reduced walking comfort.

The goal of this study is to compare the kinematics and kinetics of walking in
a FOS with a standard shoe in diabetic neuropathic patients.

The study has a cross-sectional design. Using three-dimensional movement
analysis and in-shoe pressure measurement, the gait while wearing FOS and a
standard shoe will be compared. Using reflective markers on the lower
extremity, the movements of the segments of the lower extremity will be
registered by eight camera*s. Ground reaction forces will be measured using
force plates that are set flush in the floor. In-shoe pressure measurements
will be doe using flexible insoles that are placed between the foot and the
insole and with which the pressure distribution is assessed.

Patients walk over a 12-meter walkway in two conditions per shoe: a
self-selected walking speed and a constant walking speed. Per condition, 5
successful trials will be collected. Walking comfort in both shoe conditions
will be assessed using a visual-analogue scale.

Patients will be asked to walk multiple times (minimal 15) across the gait lab
while wearing a FOS and a standard shoe. The intensity of walking will not be
different to the normal daily walking intensity. Moreover, patients will be
given sufficient time to rest between conditions. The measurements (including
subject preparation, questionnaire assessment and the actual walking) will take
in total approximately 90 minutes.

The risk associated with participation in the study is neglectable. Patients at
risk for which wearing a FOS is a contra-indication will be carefully excluded.
Additionally, the FOS is already used widely in normal clinical diabetic foot
practice for treatment of plantar ulcers.