A hand-held electro-mechanical exciter for multi-frequency peripheral neuropathy assessment

Abstract

Diabetes is becoming alarmingly common worldwide and is associated with long-term complications. One of the major and common complications of the disease is peripheral neuropathy, which causes loss of sensation in the patient's limbs due to the degeneration of sensory nerves. Loss of sensation often allows injuries to get unnoticed, which increases the risk of infections that may lead to ulcers and amputation. Several tests are used as part of peripheral neuropathy screening, one of which is the vibration perception threshold (VPT) test. Most of the existing instruments for VPT testing apply a stimulus at a single frequency while gradually increasing the vibration acceleration until the stimulus is felt and reported by the subject. Nevertheless, recent studies have shown that performing VPT at several frequencies offers a comprehensive VPT assessment. Moreover, the literature indicates that VPT evaluation is affected by excessive pressure that may be applied by the operator while the vibrators head is in contact with the skin. In this work, we describe the design of a hand-held exciter instrument capable of applying multifrequency stimuli in the range 4 Hz 500 Hz and that prevents excessive pressure from being applied by the operator to the subjects skin.