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In Depth Tutorials and Information
figure 2.1
Structural changes in the neuropathic foot
and is often referred to as a polyneuropathy. Motor neuropathy can cause
wasting of the small muscles of the foot. This can lead to characteristic
structural changes, including claw toes and prominent metatarsal heads
(
van Schie et al 2004
) (
Figure 2.1
).
When this is coupled with sensory loss, these areas are particularly
vulnerable to increased repetitive pressures and altered time loading,
resulting in callus formation, which is known to be the precursor to foot
ulceration (Young 1992) (
Figure 2.2
).
Foot pressure systems (
Figure 2.3
) can be useful in clinical practice as
well as in research in order to evaluate the impact of increased foot pres-
sure and time loading and the effect of orthoses in dealing with these
problems. It is also useful to evaluate if by offloading one area of the foot,
another vulnerable area is created.
Many of the gait abnormalities recognised in patients with diabetes are
a direct consequence of motor neuropathy which leads to muscle wasting.
Atrophy of the muscles in the foot can result in an altered arch profile,
typically presenting in the diabetic patient as a high-arched foot. The
increase in arch height reduces the area of the foot that makes contact
with the ground, resulting in a further increase in pressure under the
contact areas. The site that is known to be subject to increased pressure
is under the first metatarso-phalangeal joint and together with sensory
neuropathy it becomes an area of potentially increased time loading.
