Osteoarthritis develops when cartilage (the cushioning material that covers the ends of bones in joints) deteriorates. The reason this happens is not entirely understood, but several factors, including certain injuries, can increase the risk. A study published in the British Journal of Sports Medicine
(May 2019) examined the connection between knee injuries and osteoarthritis. The researchers reviewed results of 53 studies that included a total of about 1 million adults who had an injury of the anterior cruciate ligament (ACL), an injury of the meniscus or a combination of knee injuries. (The ACL is a ligament in the knee, and the meniscus is a C-shaped piece of cartilage between the two bones at the knee.) The odds of developing knee osteoarthritis were more than four times higher following an ACL injury and more than six times higher after a meniscal injury or combination of injuries.