Diabetes is a metabolic disease involving also the peripheral nervous system. Common problems are reduced sensation in hands and feet. Impaired tactile discrimination in the hand has serious consequences for hand function since a well-tuned sensory feedback is necessary for fine motor functions and grip strength of the hand.

Moreover, decreased sensation of the hand deprives the patient of an important sense – the sense of touch - with considerable consequences for all activities of daily life and social interaction. Impaired sensation in the foot introduces a risk for skin ulceration since the patient looses protective sensation and can easily injure the skin.

The loss of sensibility in the hands in combination with retinopathy is extra severe since this may significantly decrease the patient’s ability to read Braille with their fingers.

The Carpal Tunnel Syndrome (CTS) is more common on diabetes patients compared with the healthy population. An early detection is important because a surgical measure do have a good recovery prognosis, i.e. to get a considerably improved sensibility in the hand.

Assessment of hand sensation is important for early diagnosis of diabetes and is of value for evaluation of the longitudinal progression of the disease. For the foot assessment of the protective sensation is essential for evaluation of the risk for skin ulceration. If diminished protective sensation can be detected at an early stage, the need for time consuming medical foot ulcer care and amputation is diminished.

Today's methods for routine assessment of sensation in the hand and foot are primitive and not sufficiently standardised. For investigation of foot sensibility tuning forks, working within one frequency band, are usually used.

Also for assessment of vibration sense in the hand tuning forks may be used although the electronic tuning fork – the biothesiometer – may help to make the investigation more standardised. However, both precision and accuracy are very low for that type of device. Added to this the method includes assessment of vibration sense within one frequency which has proven quite insufficient to get reliable results.