An assessment of vibration threshold using a biothesiometer compared to a C128-Hz tuning fork

A standardised method of assessment of vibration threshold (VT), with a C128-Hz tuning fork (TF), was compared to VT measured with a biothesiometer in normal patients free of neurological disease at four separate bony points. The biothesiometer is more accurate compared to a timed tuning fork. The accuracy of both declined with patient age, however, especially for patients older than 50 years. The longer the nerve tested, the greater the age-related decline. The C128-Hz tuning fork, provided consistently applied, may be meaningfully employed at the thumb or hallux proximal nail fold to assess VT-TF at the bedside, but remains less able to discriminate VT at all ages.