Handheld Device Reduces Tremors

Pauline Anderson

March 11, 2014

A small, handheld device stabilizes a spoon and reduces tremor, which allows patients to better carry out tasks such as eating, a new study shows.

The compact and lightweight device (it weighs 100 g) could improve the quality of life for patients with essential tremor, who identify eating soup as among the most difficult tasks to perform, said study author, Kelvin L. Chou, MD, Thomas H and Susan C Brown Early Career Professor, University of Michigan, Ann Arbor.

The pilot study was published online in Movement Disorders.

Counteracting Tremor

Developed by Lift Labs of San Francisco, California, the device resembles a large electric toothbrush. It has a detachable spoon, a motion-generating platform, a controller/sensor, and a rechargeable battery. The spoon can be removed to be cleaned or replaced.

The device works by detecting the frequency at which a tremor oscillates, quickly counteracting that motion, explained Dr. Chou. For example, if the tremor motion is upward, the device moves downward. "So even though the hand is tremoring, the spoon stays stable."

Dr. Kelvin L. Chou

The study included 15 participants, 5 of whom had received deep brain stimulation (DBS).

Researchers tested the patients on 3 tasks using a prototype device: holding, "eating" foam blocks, and transferring the blocks, each performed with the device turned on and off, in random order. Two patients were tested by using their nondominant hand because tremors in their dominant hand were too severe with their deep brain stimulator turned off.

To evaluate overall tremor severity, researchers used the Fahn-Tolosa-Marin Tremor Rating Scale (TRS). As well, patients rated their improvement using the Clinical Global Impression Scale (CGI-S).

TRS scores improved significantly on all 3 tasks with the device turned on (mean changes in holding, 1.00 [P = .016]; eating, 1.47 [P = .001]; and transferring, 1.33 [P = .001]).

The changes meant going from "spilling to minimal spilling" when eating or transferring, which represented a clinically significant difference, said Dr. Chou. "The subjects still had tremor in the hand, but they could actually eat from the spoon without spilling any foam boxes, and when they transferred the foam boxes from the spoon to a cup about a foot away, they had less spilling."

The base of the spoon contains microelectronics that sense and cancel out hand tremors

CGI-S scores did not improve with the holding task but did improve significantly with eating (mean change: 2.13; P = .000) and with transferring (2.27; P = .013). This change, said Dr. Chou, represents a "minimal to moderate" improvement on average.

He noted that some patients were so impressed with the device that they said would be eager to get one when it became available. Since the study completion, it has become commercially available, at a cost of $295, through www.liftlabsdesign.com.

Accelerometer recordings showed that the device reduced tremor by 71% to 76%.

The patients and the neurologist were blinded as to whether the device was turned on. However, while the device is silent, it may have been impossible to achieve true blinding, noted the authors.

Try Before You Buy

Rodger J. Elble, MD, PhD, chair, Movement Disorder Society task force on tremor, and professor, neurology, Southern Illinois University School of Medicine, Springfield, who has tested the device himself, agreed. "You can feel the mechanical movement counteracting your hand movement," he told Medscape Medical News.

Dr. Elble has recommended the device to patients after using it while mimicking a tremor. "I faked a tremor to see how steady the spoon was, and it definitely counteracts the oscillation; there's no doubt about that."

But it would be nice if patients could try out the device before purchasing it to see if it works for them, he said.

The fact that 2 patients with severe tremors without DBS stimulation prevented the use of this device in their dominant hand suggests that it might not be suited for severe tremors, the authors write. Dr. Elble agreed, but added that most patients with essential tremor have mild to moderate tremors.

Because the spoon is detachable, patients may eventually be able to use the device to eat by using a fork, put on lipstick, or perform other tasks. The company is working to develop additional attachments, said Dr. Chou.

The study was supported by a grant from the National Institutes of Health. Dr. Chou has disclosed no relevant financial relationships. First author Anupam Pathak, PhD, is the CEO and founder of Lift Labs Design and an inventor on 2 patents for Active Cancellation of Tremor technology. Disclosures for other authors are available in the publication. Dr. Elble has disclosed no relevant financial relationships.

Movement Disord. Published online December 27, 2013. Abstract

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.

processing....