As medical treatment of diabetes mellitus improves, the life expectancy of diabetic patients is prolong and plantar ulceration, a long-term ed complication of diabetes mellitus, has become more prevalent than ever. Although many risk factors for diabetic plantar ulceration have been reported, most of them have been based on common sense, rather than on empirical evidence. Because prevention, treatment, and education of patients with diabetic plantar ulceration needs to be based on the know ledge of risk factors, it is therefore important to perform a clinical study in order to explore the risk factors by system atic observation and statistical analysis.

Data from a cross-sectional routine clinical evaluation and a longitudinal ulcer healing record were combined retrospectively to generate a new set of variables that indicated the prior conditions, present conditions, and future outcome of patients visiting a diabetic foot clinic. Special attention was paid to the patients' past history of ulcer and am putation, demographic data, quantitative sensory tests, plantar pressures, foot care habits, daily activity profile, and delayed healing.

The results revealed that the existence of a diabetic plantar ulcer at the first visit was related to patients' past history of prior plantar ulcer and amputation, increased perception threshold to vibration and pressure, prolonged duration of diabetes mellitus, and frequent barefoot walking. The ulcers also result in increased contact with medical professionals which in turn appeared to cause the patients to be more compliant with foot care and to reduce their foot activity.

P resenting diabetic plantar ulcer in future follow-up was related to patients' lifetime history of plantar ulcer and amputation, increased perception threshold to vibration and pressure, increased plantar pressures, and frequent barefoot walking. The behavioral factors such as frequent barefoot walking and activity level and the biomedical factors such as monofilament perception threshold, previous ulceration, and am putation were independently related to plantar ulcers presented at the first visit or at future follow-ups in a multiple regression model.

The multiple regression analysis of 22 accurately measured, continuously healing ulcers treated with total contact casts showed that ulcer size, calculated as the square root of the quotient of length times width divided by 4 could be predicted by the initial size, the num ber of days after initiating treatment, and its initial size multiplied by the number of days after initiating treatment. Deviations from the regression model were associated with decreased systolic toe pressure, no contact casting, and poor compliance with non-weight bearing.