Nepal, Sept. 16 -- 25 years ago, Meena Risal, now 88, began noticing a twinge in her knees whenever she stood or walked for too long.

"It was easy to ignore at first. But gradually, the ache turned into persistent pain. My knees started swelling, they felt stiff in the mornings, and even simple movements became increasingly difficult," she says. For years, Meena dismissed the discomfort as a normal part of aging. It was only more than a decade later, when the pain began to impair her mobility, that she sought medical attention.

Her symptoms were characteristic of osteoarthritis, a chronic joint disease that affects an estimated 600 million people worldwide. That number is expected to reach one billion by 2050.

In Nepal, its true burden...