Multifrequency vibration could improve early detection of diabetic neuropathy

High blood sugar can cause damage to diabetics’ nerves and could eventually lead to foot ulcers and, in some cases, amputation. Swedish researchers have found that patient perception of vibrations delivered at varying frequencies could become a better way to detect foot ulcers early.

The study, presented Tuesday at the annual meeting of the European Association for the Study of Diabetes, used the CE marked VibroSense Meter from Malmö, Sweden-based VibroSense. The device is indicated for the early detection of impaired vibration sensibility in the hands and fingers that may be caused by neurological, vascular or musculoskeletal injuries, according to the company. It has been used to detect neuropathy in miners, as well as other industries where vibration injury is common, such as construction and auto repair.

The researchers, led by Dr. Eero Lindholm of Skånes University, tested the sensory perception of 364 Type 1 diabetics with and without foot ulcers and 137 healthy people. “The results are very promising and could lead to improved early detection of diabetic foot ulcers,” Lindholm said in a statement. “We have found a strong correlation between foot ulcers and impaired tactile sensation at low vibration frequencies.”

Unlike the current method, where a physician applies a tuning fork to the patient’s foot, the VibroSense delivers vibrations at frequencies ranging from 4 Hz to 500 Hz. For the study, the researchers used frequencies from 4 Hz to 125 Hz. The ability to deliver multiple frequencies makes the device a more sensitive measure of sensory loss, VibroSense Marketing Director Ulf Rogers told FierceMedicalDevices. It also allows for the stimulation of several mechanical receptors in the skin, which respond to differing frequencies. Additionally, the device offers a more controllable way to deliver vibrations as compared with a tuning fork, where the pressure on a patient’s foot depends on who is conducting the examination, Rogers said. It delivers a controlled sequence of vibrations of increasing frequency until the patient can feel them and presses a button. This causes the vibrations to then decrease in frequency until the patient can no longer sense them and presses a button.

The early detection of diabetic neuropathy is key because it develops gradually, and patients may not get a diagnosis until the damage has been done. Diabetic foot ulcers affect about 10% of diabetics at least once in their lives, and they precede more than 80% of amputations in people with diabetes, according to the statement. There is no cure, but medications and controlling blood sugar can help ease symptoms.

The study will continue for another three years, Rogers said. It will include more testing on healthy people to establish a baseline for vibration sensitivity to better determine what is not normal.