I saw a report that people with severe knee arthritis can use electricity to avoid having a joint replacement. How does this work?

Several studies have been done using electrical currant to stimulate cartilage growth and repair. Surface electrodes on the skin are placed directly over the knee for eight or more hours each day.

The current is delivered by a portable, battery-operated stimulator. It’s not an overnight cure. Patients must use it everyday for at least a year (or more) to be effective. But up to 60 per cent of the patients with moderate to severe osteoarthritis (OA) who used it have success avoiding surgery.

It works by delivering a negative charge to the ions in the cartilage cells. Biochemical influences signal the cartilage to start the process of healing and repair. The patient doesn’t feel anything. The intensity of the electrical signal is kept just below a tingling sensation.