Prediction of Insensate Peripheral Neuropathy in Diabetics using “Semmes- Weinstein Monofilament” Examination

Abstract

Background & Objective Diabetic Peripheral neuropathy (DPN) is a debilitating long term complication of Diabetes Mellitus, but has the advantage of being diagnosed early and its course slowed. The Semmes-Weinstein Monofilament examination is appropriate for early diagnosis of neuropathy, as a simple screening instrument generalizable to the
clinical setting. The aim of this project is to study the incidence of peripheral neuropathy
among diabetics using the 5.07/10 g Monofilament, and determine the most sensitive
site on the foot for its use.

Methods A random sample of 120 patients were studied. Monofilament was applied to the plantar surface of 4 sites of both feet. Inability to perceive the sensation at any one site before the monofilament bends within a contact time of 2 seconds, was considered abnormal. The data were analyzed using SPSS 17 Statistical Program. Two-sample t-Test
was done to study the prevalence.

Results and Interpretation Total of 42.5% subjects were recently (less than or equal to one year) diagnosed as cases of diabetes. Out of these subjects, 27% had already some form of neuropathy present in their feet. It was observed that the duration of morbidity significantly affects the setting in of neuropathy among diabetics (p = 0.005), especially
patients with diabetes for over 10 years tend to develop neuropathic symptoms over time. The most commonly affected site was found to be the plantar aspect of the great toe of the left foot (83%), in accordance with the gait cycle.

Conclusions The management of DPN needs to be individually based on co morbidities and tolerability to medications. Determination of an appropriate site for testing the Monofilament reduces the possibility of false negatives, and makes this bed side tool more suitable for use for determination of neuropathy.