Monofilament assessment of neuropathy in a community diabetes clinic

To compare the detection of diabetic neuropathy using monofilament, cotton wool, pinprick, vibration sense and symptom evaluation.

The diabetes clinic of a community hospital.

Two examiners evaluated 89 women with diabetes mellitus (DM) using a 10 g monofilament, cotton wool, pinprick and a 128 Hz tuning fork after completion of a University of Texas subjective peripheral neuropathy verbal questionnaire.

Vibration sense was abnormal in either foot in 8% of subjects. Neuropathy as defined by monofilament, cotton wool and pinprick was present in 26%, 3% and 6% of patients respectively. The respective kappa values (kappa) for the comparison between monofilament neuropathy and cotton wool neuropathy, pinprick neuropathy and symptom-defined neuropathy were 0.18, 0.21 and 0.06. The kappa-value comparing monofilament and tuning fork-defined neuropathy was 0.24. There was fair agreement between 10 versus 3 sites (kappa = 0.60).

More abnormalities were detected using the monofilament compared with cotton wool or pinprick. There was poor concordance between symptoms and clinically detected neuropathy. The ideal number of sites that need to be evaluated is still contentious.