Osteoarthritis finding sheds new light on HA injection controversy

Injections of hyaluronic acid (HA) are a common treatment of pain in osteoarthritis of the knee - a condition that affects 27 million Americans according to the Centers for Disease Control and Prevention. The injections replace natural HA that has depleted from one's joints, which can cause pain and stiffness due to the lack of lubrication between bones moving against each other.