VibraTip (McCallan Medical) is a device resembling a small keyring fob that provides a near‑silent vibration of consistent amplitude, at a frequency similar to that of a calibrated tuning fork. It is intended to test a person's vibration perception during routine checks for diabetic peripheral neuropathy in people with type 1 or type 2 diabetes.
The VibraTip probe is applied to the patient's foot twice: once while not vibrating and once while vibrating. The patient is asked to indicate when they feel the vibration. If the vibration is not detected, this may suggest the presence of diabetic peripheral neuropathy and the clinician may investigate further. VibraTip is intended as an alternative to, or replacement for, the devices that are currently used in NHS clinical practice for testing foot sensory function, such as the 10 g monofilament (light touch sensation) and the calibrated tuning fork or biothesiometer (vibration perception). The device is designed to provide a consistent application compared with the variable vibration and cold touch of the tuning fork, and to offer continuous operation over its battery life compared with the 10 g monofilament, which needs resting after every 10 full patient foot examinations.
VibraTip received a CE mark in March 2010 and is indicated to test for vibration perception in the foot during routine checks for diabetic peripheral neuropathy.
The cost of VibraTip stated in the sponsor's submission is £9.95 (excluding VAT) per device.
The sponsor's claimed patient and healthcare system benefits for VibraTip are:
The ease and speed of the test, together with the device's reliability, means earlier diagnosis of neuropathy, leading to improved foot care, helping to prevent ulcers and amputations.
Less user variability, making the VibraTip test for diabetic peripheral neuropathy more consistent compared with a tuning fork test.
The ease and speed of testing means little user training is needed.
Smaller size makes it more portable and accessible than comparators.
Easily cleaned and tolerant to regular, routine cleaning facilitating compliance with infection control guidelines.
NICE guidelines on type 2 diabetes foot problems and type 1 diabetes both recommend a structured programme of regular (annual) foot surveillance, risk assessment and education by trained personnel to raise awareness of the condition. The annual foot examination should include a visual check, palpation of pulses and assessment of foot sensory nerve function. The sensory nerve function component may include assessment of touch using a 10 g monofilament, or a test of vibration perception using either a biothesiometer or calibrated tuning fork. In clinical practice, biothesiometers are reported to have been replaced by neurothesiometers which work in the same way, but have a self‑contained battery, allowing for greater portability. The 10 g monofilament should not be used to test more than 10 people per session and should be rested for 24 hours thereafter. Both NICE guidelines are currently being updated, with anticipated publication in 2015.
Classification of risk (low, increased, high, ulcer present) in the annual check is on the basis of sensation, pulses, deformity, skin changes or previous ulcers. This may result in referral to a specialist foot protection team, comprising podiatrists, orthotists and foot care specialists (nurses trained in dressing diabetic foot wounds and diabetologists with expertise in lower limb complications). The assessment will typically result in more frequent foot checks (every 3‑6 months), with a vascular assessment and an assessment of footwear. For people at particularly high risk of ulcer formation, foot examinations may take place every 1‑3 months, and include an intensive foot care education programme and the use of specialist footwear insoles and skin and nail care. Self‑monitoring and self‑inspection is both taught and encouraged.
There is currently no agreed standard on the number or location of the sites on each foot which should be examined when testing for touch sensation or vibration perception.