[Cutaneous sensibility threshold in the feet of diabetic patients with pressure specified sensory device: an assessment of the neuropathy].

OBJECTIVES: Neuropathy is a severe progressive loss of protective sensation in the feet, increasing patient vulnerability to mechanical trauma and consequently more prone to development of chronic wounds, major distortion of the foot bone architecture and to eventual limb amputation. Prophylaxis should be enforced to avoid foot ulceration and for this purpose, evaluation of the degree of loss of sensation on the skin is essential. The PSSD (Pressure Specified Sensory Device) was developed to quantify the threshold of pressure applied to the skin that the patient might recognize as positive. Pressure of one or two points is tested both statically and with movement, thus assessing the function of fast and slow response nerve fibers.

METHODS: 33 diabetic patients, type II, with no previous history of wounds on the lower extremity were studied. The tests used were, one point static, one point moving and two points, static and moving on the cutaneous territory of the fibular nerve and posterior tibial nerve (two territories - medial plantar and calcaneous nerves).

RESULTS: Altered values were observed for the static and dynamic tests over the three nerve territories studied. Differences were statically significant (p < 0.05). This numeric quantification of the threshold of pressure supports the evaluation of the status of the fiber/receptor structures as well as the functional deficit subsequent to diabetic neuropathy.