Researchers at Cornell University have developed a new soft robotic glove called EdemaFlex, designed to alleviate swelling in individuals suffering from edema. The innovative device features over three dozen actuators distributed across all five fingers and the palm, demonstrating a significant potential for reducing hand volume by as much as 25% following just one 30-minute session.
In a preliminary study involving seven participants, the glove proved safe for unsupervised home use, marking a significant advancement in non-invasive treatment options for edema. The research was led by Cindy (Hsin-Liu) Kao, an associate professor of human-centered design at the College of Human Ecology. Previously, Kao had developed KnitDema, which established the efficacy of shape-memory alloy actuators for providing gentle pressure to alleviate swelling in individual fingers.
Advancing Soft Robotics for Health
The latest iteration of this technology combines the insights gained from earlier projects, including MediKnit, which focused on improving the fabrication of soft medical devices. According to Kao, who directs the Hybrid Body Lab, the research team aims to expand their focus beyond the upper extremities, with aspirations for applications in women’s health and other bodily areas.
Kao and her colleagues published their findings in the article titled “EdemaFlex: Textile-Based Soft-Robotic Platform Toward Personalized Hand Edema Therapy” on February 24, 2024, in the journal npj Flexible Electronics, a publication of Nature. The study co-author, Dr. Joan Stilling, an assistant professor of clinical rehabilitation medicine at Weill Cornell Medicine, provided essential medical and design consultation throughout the project.
EdemaFlex operates by applying sequential pressure from the fingertips toward the palm and wrist, effectively pushing excess fluid out of the swollen hand. The glove incorporates thread-like shape memory alloy (SMA) springs woven into its knitted fabric, which activate through a compact printed circuit board. This design allows for a total of 37 actuators—six in each finger and seven in the palm—to work in unison, delivering targeted compression to facilitate fluid mobilization.
Personalized Design and Clinical Collaboration
The glove is made from two types of yarn, including a blend that contains 17% spandex, ensuring flexibility and comfort. Importantly, the duration and intensity of the compression can be tailored to meet the specific needs of individual patients.
One of the challenges faced by the research team was developing an actuator pattern that would not interfere with the lymphatic or venous systems of the hand. Stilling emphasized the importance of clinical input, stating, “Clinicians help to identify specific patient needs based on their individual anatomy and reason for hand swelling, like patterning the compression location and intensity or adjusting the glove design to be more easily worn when the hand is difficult to open.”
In the study, participants diagnosed with hand edema underwent a three-day evaluation, which included a home trial. Clinicians performed fittings with each patient, sending hand measurements back to the lab through an innovative software platform. Kao noted, “An important part of what we did was the introduction of this software platform. It allowed us to take a bitmap of the hand and feed the information into the knitting machine to produce a first prototype.”
The collaboration between the researchers at Cornell and clinical experts at Weill Cornell Medicine highlights the potential for developing effective and user-friendly devices. As noted by Stilling, this partnership facilitates the creation of innovative, personalized solutions that address real-world medical challenges. The EdemaFlex glove represents a promising step forward in the field of soft robotics for health care, paving the way for more accessible treatment options for those affected by edema.
