Researchers at the University of Texas at El Paso and Harvard tested a device that sends pulses to nerves in your ear to reduce knee pain. The treatment helped 11 out of 30 people with arthritis feel better after just one hour.
Why it matters
This approach targets your nervous system, not damaged knees, meaning fewer side effects and better results than current treatments.
Most treatments for knee pain focus on repairing damaged cartilage and joints. However, these researchers approached the problem from a different angle: People with knee arthritis have an imbalance in their nervous system that makes pain worse.
tVNS is given through the skin over the auricular branch of the vagus nerve, seen in magenta. Diedrich, A et al. (2021)
How it works
The treatment, transcutaneous auricular vagus nerve stimulation (tVNS) is placed on your ear for 60 minutes. It sends gentle pulses to the vagus nerve, which controls your body's "rest and digest" functions.
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The vagus nerve is part of your parasympathetic nervous system.
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This system balances out your sympathetic nervous system, which handles stress and danger responses.
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When these systems are out of balance, you feel more pain.
By the numbers
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The study included 30 people with knee arthritis.
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About 37% felt noticeable pain relief after one treatment session.
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This was the first clinical trial in the U.S. to test this method for knee pain.
The challenge
The FDA already approves tVNS devices for epilepsy and depression, but not for knee pain yet. The researchers need to run larger studies first.
The next step: A randomized controlled trial using more people divided into a group that gets the real treatment, and the other, a fake treatment, to compare results.
The takeaway
Knee arthritis can turn simple tasks into challenges — tying your shoes, climbing into a car, or walking down stairs. This new ear-based treatment offers hope for millions suffering from arthritic knee pain. While current treatments like pain medications and physical therapy help some people, they often fall short with side effects or only temporary relief.
