Just because you injured your knee does not mean you'll have problems as you age. However, significant injuries to the knee and hip have been found to increase the risk of osteoarthritis in these joints. Researchers tracked 1,337 medical students over a period of nearly twenty years to see whether people with knee or hip injuries would eventually have problems with osteoarthritis. They found that a higher percentage of people with injuries of the hip or knee in the younger years ended up having arthritis in the joint they had injured. People who are at risk because of an earlier injury should consider seeking advice on ways to improve the health of their joint and to prevent problems in the future.