Multi-frequency Vibrometry Demonstrates Strong Correlation with Nerve Conduction Velocity in Detection of Diabetic Peripheral Neuropathy

This fresh research out of Sweden by Ekman et al assessed the ability of multiple vibration frequencies to detect diabetic peripheral neuropathy (DPN). They found that combinations of high (125 Hz and 250 Hz) and low ( 4 Hz and 8 Hz) frequencies were most effective with an area under the curve (AUC) of 0.83. They subsequently searched for correlations  between vibration testing and nerve conduction velocity (NCV) testing. Interestingly, the strongest correlation with NVC testing was noted when results from the sural nerve were negatively correlated the 5th metatarsal head vibration testing at 125 Hz ((Spearman correlation: r=-0.715, p<0.0001). This varies from current clinical practice guidelines recommending vibration testing with a 128 Hz tuning fork applied to the dorsal aspect of the interphalangeal joint of the great toe.

Another interesting finding in the results but not discussed in the paper were the correlations of NCVs and vibration testing at 64 Hz and 125Hz at the first metatarsal head. Positive correlations of r=0.66 (64 Hz) and r=0.64 (125 Hz) were noted. These correlations support current clinical practice guidelines and may suggest that 64 Hz is a good alternative to use of the 128 Hz tuning fork. Our ETFMx offers multiple frequencies for those providers interested in expanding their options in this regard.