Guided by an old technique, researchers have discovered that vibrations can reduce the intense pain caused by injury or arthritis, without using drugs. Crude personal massagers have long been used to soothe aches, but relief is often fleeting. Orthopedic surgeon Dr. Ranjan Vhadra has refined and fine tuned the vibration method for seven years, discovering the "sweet-spot" frequency: 140Hz. He's packaged it into a personal vibration device, branded "Kneease." This vibrations therapy, as it's called, was apparently first used during the Civil War, when drummer boys found they could relieve the pain of amputees by playing on their stumps. Now modern researchers say our central nervous systems can't carry pain and vibration signals simultaneously. So if you introduce high frequency vibrations to the site of pain, the pain signals won't reach the brain.