The tactile circumferential discriminator. A new, simple screening device to identify diabetic patients at risk of foot ulceration.

Abstract

To evaluate the tactile circumferential discriminator (TCD) (Tacticon Medical Enterprises, West Chester, PA), a new, simple, handheld quantitative sensory testing device, in the identification of patients at potential risk of neuropathic ulceration. Patients with diabetes (n = 133) attending the Manchester Diabetes Centre or diabetic foot clinic seen within a 5-week period were assessed using the TCD, monofilaments, and vibration perception threshold (VPT) measured over the hallux. The sensitivity and specificity of each method in the identification of "high-risk" patients were compared. The TCD was easy to use, and there was a highly significant correlation between the results obtained compared with both filaments and VPT (P < 0.0001). Similarly, in the identification of patients at risk of ulceration, the TCD agreed with VPT in 75.2% of cases and with the monofilaments in 78.9%. In the identification of the 37 foot ulcer patients, TCD was highly sensitive (100%) but less specific (58.3%) than VPT (86.5%; 79.2%) and the monofilaments (91.9%; 76.0%). These data suggest that the TCD is a simple and reliable new technique for population screening for neuropathy and foot ulcer risk.