Comparison of quantitative sensory-threshold measures for their association with foot ulceration in diabetic patients

We compared the accuracy of cutaneous pressure perception-threshold measurements with that of other sensory-threshold measurements for detecting diabetic foot ulcer patients. Three hundred fourteen non-insulin-dependent diabetic patients were studied, of whom 91 had either a current foot ulcer or a history of foot ulceration. Foot ulcer patients had much higher pressure perception thresholds at the hallux than those without foot ulcers (mean +/- SE 4.63 +/- 0.05 vs. 3.54 +/- 0.04 U, P less than 0.001). The magnitude of association was higher than that for vibration thresholds and markedly greater than those for cool and warm thresholds. Pressure thresholds were highly accurate for identifying foot ulcer patients. At a threshold level of 4.21 U, the sensitivity was 0.84, with a specificity of 0.96. At similar sensitivities for vibration and thermal thresholds, specificities were lower. Foot ulceration and cutaneous pressure perception threshold are strongly associated. Pressure-threshold measurements are extremely accurate and perform at least as well as other quantitative sensory tests in identifying foot ulcer patients. Assessment of the foot pressure threshold may have promise as a simple and inexpensive method for detecting diabetic patients at risk for foot ulcers.