People are sometimes told they are "at risk" of developing arthritis at some point in the future. What does this mean? First it is important to understand the causes of arthritis. There are many factors that can contribute to the development of arthritis, and people with arthritis may have more than one of these contributing factors.

Here are some causes of osteoarthritis:

Old Injuries - Major injuries that damage the cartilage in the joint can result in arthritis later down the road. This is known as post-traumatic osteoarthritis. Examples of this are any fractures that enter into the joint, or an ACL tear, which is a common sports injury.

Weight - Being overweight puts more force across the joints with daily activities. This is especially a problem in the hips and knees. Being overweight may also accelerate the development of arthritis in a joint that has had a previous injury.

Age - As we age, cartilage is not able to repair itself as well. Also, the characteristics of cartilage change with age, making it more susceptible to injury.

Genetics - It is not known for certain how much of a role heredity plays in arthritis, but we know that it does have a role. Some researchers suggest that genetics contribute about 50% to the overall development of arthritis. There is research underway now to determine the specific ways in which heredity is related to arthritis.

Infection - Having a joint infection can damage the cartilage, and lead to arthritis. There are also other medical conditions related to the development of arthritis.

Repetitive activities - People in specific occupations may have a higher risk of developing arthritis. Work involving heavy physical labor or repetitive assembly line activities may increase the risk for arthritis in certain joints. Also, some high-level sports may be related to an increased risk for arthritis. For example, elite javelin throwers and high jumpers tend to be more prone to hip arthritis.