There are different causes, such as repetitive actions and autoimmune diseases, for the different forms of arthritis. Although genetics may play a role in the disease, scientists believe it is an indirect role, so the genetic predisposition is affected by environmental factors, such as broken bones, which actually damage the joint. 

The risk factors that predispose a person to a higher chance of developing the disease are 

Age - Males over 45 years and females over 55 years are more likely to have arthritis than younger individuals. 

Sex - Males are more likely to develop the degenerative form of arthritis and females more likely to develop the autoimmune form. 

Obesity - Excess weight of the individual can have a degenerative effect on the joints, which may appear in later years. 

Injury - Professional sports players or even long-time enthusiasts who have had a major joint injury or other professionals who have repetitive occupational injuries to the joint develop arthritis more readily.