Morning stiffness may also occur in the hands when you are examined for the absence of rheumatoid arthritis. Although morning stiffness is mainly caused by rheumatoid arthritis, diseases such as systemic lupus erythematosus, ankylosing spondylitis, osteoarthritis and carpal tunnel syndrome may also cause morning stiffness, and doctors will usually combine the patient’s clinical symptoms and signs with various types of tests to confirm the diagnosis.