Patients with diabetic neuropathy often can’t feel injuries on their feet, which can lead to ulcers and amputation. Siren’s microsensor-embedded socks catch early signs of inflammation.
This week, medical device company Siren raised $11.8 million in funding for a smart wearable on course to change the lives of patients with diabetic neuropathy.
The Mayo Clinic explains that diabetic neuropathy can cause nerve damage, most often in the legs and feet, resulting in less sensation in those areas. Patients with this condition may not notice small injuries on the lower legs and feet, which leads to inflammation and if not tended to, an ulcer. Siren says this condition leads to an average of 100,000 lower extremity amputations in the U.S. every year.
To remedy this issue, Siren has developed socks interwoven with microsensors that monitor the temperature of the feet—a spike in temperature indicates inflammation—and communicates data via Bluetooth. These socks are meant to be worn daily, and as such, are machine washable and dryable.
The sensor-embedded socks send temperature data via Bluetooth. Image used courtesy of Alexander M Reyzelman et. al
Inspiration for the Temperature-Sensing Socks
The inspiration for Siren socks comes from its CEO, Ran Ma, a biomedical engineer who graduated from Johns Hopkins University and came from a family of doctors. Ma she wanted to create a wearable that took a preventative approach to diabetic neuropathy. Currently, Ma explains, doctors must manually check their patients’ feet for ulcers.
Should a doctor take a preventative approach to this condition, he or she must take the temperature of a patient’s foot in six specific areas that are most at risk for inflammation. If the body is fighting an infection on the foot, unnoticed by the patient, a doctor can measure a temperature spike in the region of infection.
Siren developed a technology known as Neurofabric that conducts the same temperature measurement a patient might expect in a clinic; only, this temperature measurement can occur continuously and autonomously, sending warnings from a Bluetooth hub on socks to the patient and his or her doctor via an app.
How Does Neurofabric Work?
An observational study on Neurofabric technology reveals the electronic design behind the product.
The “smart textile” in the socks weaves microsensors directly into the fabric. These microsensors embedded in the fabric connect to a small tag or capsule that contains a Bluetooth chip, a microcontroller unit, and a battery. The sock includes six sensors at various points at the bottom of the patients’ feet: the hallux, the metatarsal points (1, 2, and 5), midfoot, and the heel.
The left image shows the tag that encapsulates the Bluetooth chip, the MCU, and the battery. The right image shows six temperature-measured places of the foot. Image used courtesy of Alexander M Reyzelman et. al
The sensors measure the temperature at these points in 10-second intervals, storing data in the tag and sending information on each pair of socks via Bluetooth to the user’s mobile phone app. The user can adjust the settings of the app to send alerts when his or her feet spike in temperatures—an early indication of developing ulcers.
Siren feels confident that these smart socks can give patients peace of mind in between doctor visits, especially since ulcers can take only hours or days to develop.
Siren’s History and Trajectory
Since its founding in 2015, Siren has raised $22 million in funding, including the recently funded $11.8 million. Siren also won TechCrunch’s CES Hardware Battlefield award and was named the winner of the 2018 CES Best of Innovation award.
A Forbes article on Siren socks explains that the wearables underwent heavy testing among patients experiencing Type 1, Type 2, and gestational diabetes in the United States and Canada. These patients reported that the socks felt completely normal and that there was no discomfort.
Siren socks. Image used courtesy of Siren
Siren says its Neurofabric has the potential to be about 87% more effective in treating diabetic foot ulcers than conventional methods. Ran Ma feels this technology of interwoven microsensors can be expanded to other industries, varying in what kinds of data the microsensors collect.