The effects of total contact casting materials on plantar pressures

The plaster-based total contact cast (TCC) is effective at reducing high plantar pressures associated with foot ulceration in the patient with diabetes. However, the weight and the lengthy drying time which require nonweightbearing create an inconvenience for the patient. Fiberglass has been commonly used as a substitute for plaster due to the quicker drying time, although little is known about the effects of fiberglass on plantar pressures. The purpose of the study was to compare a plaster-based TCC (PB-TCC) and an all-fiberglass TCC (AF-TCC) using selected plantar pressure parameters for commonly ulcerated regions of the foot. Using a repeated measures design, 10 healthy subjects consented to walk, for four consecutive trials, along a 25-m corridor while wearing a running shoe, PB-TCC, and AF-TCC. For each of the footwear conditions, parameters of peak pressure, pressure-time integral, and contact time for the forefoot, lateral midfoot, and heel regions were recorded using the Pedar trade mark system of plantar pressure measurement. Both the PB-TCC and AF-TCC produced similar peak plantar pressures that were significantly lower (p =.001) than the running shoe. Pressure-time integrals were similar for all footwear conditions and contact time was not altered with footwear type. In summary, the AF-TCC appears to be an effective alternative to the PB-TCC for plantar pressure reduction in the management of neuropathic foot ulceration.