Foundations for practice: Neuropathy examinations

The American Diabetes Association recommends that all individuals with diabetes should be screened for protective sensation (peripheral neuropathy) in their feet at diagnosis and at least annually thereafter. Recommended tests include the 10 g monofilament test and at least one other exam either the 128 Hz tuning fork (large-fibre function), and temperature or pinprick sensation (small-fibre function) exam.^1,2,3 Combining at least two examinations will increase the sensitivity and specificity of detecting distal symmetric polyneuropathy (DSPN).^2,3,4,5 Following are the recommended procedures for the two most frequently used exams, the monofilament and the tuning fork.

The SWME is performed using a 5.07 monofilament, which is a calibrated, single-fibre nylon thread. The 5.07 monofilament exerts 10 grams of force when bowed into a C-shape against the skin for one second. Patients who cannot reliably detect application of the 5.07 10g monofilament to designated sites on the plantar surface of their feet are considered to have lost protective sensation. A positive Semmes-Weinstein monofilament result is a significant predictor of future ulceration and likely lower extremity amputation as well in patients with diabetes mellitus.⁶