Reliability of Semmes-Weinstein Monofilaments and Tuning Fork on Pressure and Vibration Sensation Measurements in Diabetic Patients

Objectives: Sensory neuropathy is the major cause of ulceration in diabetic patients. Periodical sensory examination is an appropriate method to detect neuropathy and decrease the risk of diabetic foot ulcer. Semmes–Weinstein Monofilaments (SWM) and tuning fork on/off test are widely used to assess pressure and vibration sensitivity. The present study evaluated the inter- and intra-rater reliability of SWM and tuning fork to measure pressure and vibration sensations in diabetic patients. Methods: Following ethical approval, 34 diabetic patients without foot ulceration were recruited. Feet kit SWM and tuning fork were used for pressure and vibration sensation evaluation, respectively. Measurements were performed twice on the first session with an hour interval to assess within-day reliability and the third one was demonstrated 7 days later to assess between-days reliability.  Results: Within-day Intra-class Correlation Coefficient (ICC) analysis indicated excellent levels of inter- and intra- rater reliability (ICC>0.75) for feet kit SWM in all foot regions and 128 Hz and 256 Hz tuning forks. Excellent between-days intra-rater reliability (ICC>0.75) was also obtained for SWM; however, the ICC of tuning fork was moderate. Between-days inter-rater reliability of SWM and tuning fork were high and poor, respectively. Discussion: The obtained results indicated that SWM and tuning fork seemed to be highly reliable to measure pressure and vibration sensations in diabetic patients. However, further studies are required to support the results of current study.