A new report by Fortune Business Insights predicts that the global knee replacement market will reach $12.72 billion by 2026. The market, which totaled $9.1 billion in 2018, will grow as a result of increasing osteoarthritis and other knee diseases worldwide.

The Norh American knee replacement market, the world’s largest, was measured at $4.83 billion in 2018, with more than 600,000 knee replacement surgeries performed every year, according to the report. Approximately 14 million people have symptomatic knee osteoarthritis in the United States, according to the Arthritis Foundation.

The ballooning rate of osteoarthritis is a result of a rapid increase in the aging population, and increasing rates of obesity of younger patients. The highest rate of osteoarthritis in the United States is among patients between 55 and 64 years old, but obesity increases the risk among all age groups. Women are three times more likely to need knee replacement surgery than men.

The top players in the knee replacement market, according to the report, are Zimmer Biomet, Stryker, DePuy Synthes Companies, and Smith & Nephew. These companies manufacture the majority of medical devices that are used in knee arthroplasty. In the last three years, a number of new knee replacement technologies have been launched including the ATTUNE Cementless Knee, designed for younger, more active patients.