Custom foot orthoses significantly reduced plantar pressure compared with the sham, but there were no significant differences between groups for pain or function. The high-quality walking footwear provided to both groups may explain this finding. Footwear should have greater emphasis as the clinical intervention.

BackgroundThe total contact cast (TCC) is an effective intervention to reduce plantar pressure in patients with diabetes and a plantar forefoot ulcer. The walls of the TCC have been indirectly shown to bear approximately 30 % of the plantar load. A new direct method to measure inside the TCC walls with capacitance sensors has shown that the anterodistal and posterolateral-distal regions of the lower leg bear the highest load. The objective of this study was to directly measure these two regions in patients with Diabetes and a plantar forefoot ulcer to further understand the mechanism of pressure reduction in the TCC.MethodsA TCC was applied to 17 patients with Diabetes and a plantar forefoot ulcer. TCC wall load (contact area, peak pressure and max force) at the anterodistal and posterolateral-distal regions of the lower leg were evaluated with two capacitance sensor strips measuring 90 cm2 (pliance®, novel GmbH, Germany). Plantar load (contact area, peak pressure and max force) was measured with a capacitance sensor insole (pedar®, novel GmbH, Germany) placed inside the TCC. Both pedar® and pliance® collected data simultaneously at a sampling rate of 50Hz synchronised to heel strike. The magnitude of TCC wall load as a proportion of plantar load was calculated. The TCC walls were then removed to determine the differences in plantar loading between the TCC and the cut down shoe-cast for the whole foot, rearfoot, midfoot and forefoot (region of interest).ResultsTCC wall load was substantial. The anterodistal lower leg recorded 48 % and the posterolateral-distal lower leg recorded 34 % of plantar contact area. The anterodistal lower leg recorded 28 % and the posterolateral-distal lower leg recorded 12 % of plantar peak pressure. The anterodistal lower leg recorded 12 % and the posterolateral-distal lower leg recorded 4 % of plantar max force. There were significant differences in plantar load between the TCC and the cut down shoe-cast for the whole foot, rearfoot, midfoot and forefoot (region of ulcer). Contact area significantly increased by 5 % beneath the whole foot, 8 % at the midfoot and 6 % at the forefoot in the shoe-cast (p < 0.05). Peak pressure significantly increased by 8 % beneath the midfoot and 13 % at the forefoot in the shoe-cast (p < 0.05). Max force significantly increased 6 % beneath the midfoot in the (shoe-cast p < 0.05).ConclusionIn patients with diabetes and a plantar forefoot ulcer, the walls of the TCC bear considerable load. Reduced plantar contact area in the TCC compared to the shoe-cast suggests that the foot is suspended by the considerable load bearing capacity of the walls of the TCC which contributes mechanically to the pressure reduction and redistribution properties of the TCC.

BackgroundAustralia is ranked ninth of 39 countries in the Western Pacific region most affected by diabetes. Patients with diabetes are at high risk of developing foot ulcerations that can develop into non-healing wounds. Recent studies suggest that the lifetime risk of developing a diabetic foot ulcer is as high as 25%. Few studies have reported the prevalence of, risk factors and socioeconomic status associated with, diabetic foot ulcers in Australia. The aim of this study was to evaluate the characteristics of diabetic foot ulcers in a tertiary referral outpatient hospital setting in Western Sydney, Australia.MethodsFrom January-December 2011, a total of 195 outpatients with diabetes were retrospectively extracted for analysis from the Westmead Hospital’s Foot Wound Clinic Registry. Data on demographics, socioeconomic status, co-morbidities, foot ulcer characteristics and treatment were recorded on a standardised form.ResultsDemographics and physical characteristics were: 66.2% male, median age 67 years (IQR: 56–76), median body mass index (BMI) of 28 kg/m2 (IQR: 25.2-34.1), 75.4% had peripheral neuropathy and the median postcode score for socioeconomic status was 996 (IQR: 897–1022). Diabetic foot ulcer characteristics were: median cross sectional area of 1.5 cm2 (IQR: 0.5-7.0), median volume of 0.4 cm3 (IQR: 0.11-3.0), 45.1% on the plantar aspect of the foot, 16.6% UT Wound Grade of 0C to 3C (with ischaemia) and 11.8% with a Grade 0D to 3D (with infection and ischaemia) and 25.6% with osteomyelitis. Five patients required an amputation: 1 major and 4 minor amputations.ConclusionsIn accordance with other international studies, foot ulcers are more likely to present on the plantar surface of the foot and largely affect overweight older males with a long standing history diabetes in our outpatient hospital in Western Sydney.

The offloading properties of the total contact cast can be enhanced with a 12 mm cellular urethane cushion modification. Further well-designed trials are required to understand and validate this cast technique and to demonstrate healing rates and safety in different patient populations.