No. In your joints there is a liquid called synovial fluid, which serves as a lubricant. When you cause your knuckles to crack the synovial fluid has to fill more space, and this is what causes your knuckles to make a cracking noise. Arthritis comes about when your immune system starts to cause harm to your joints. Of course, cracking your knuckles too much can still cause other problems for your joints, just not arthritis.