Osteoarthritis is a disease of the joints, and it can affect the spine (osteoarthritis in the spine is often referred to as spondylosis). Also know as degenerative joint disease, it is the most common form of arthritis, affecting some 27 million American adults. It is a separate condition from and should not be confused with rheumatoid arthritis, another painful inflammatory condition.

Osteoarthritis is caused by cartilage breakdown; cartilage provides a cushion between the bones of the joints. Healthy cartilage allows bones to glide over one another and acts as a shock absorber during physical movement. In osteoarthritis, the cartilage breaks down and wears away. This causes the bones under the cartilage to rub together, causing pain, swelling, and loss of joint motion.

What Causes Osteoarthritis?
While the process of spinal osteoarthritis is understood (as explained above), what causes this process to begin is not as well-understood.  There are several risk factors that make it more likely you'll develop spondylosis, including:

• Age – osteoarthritis affects more people over the age of 45
• Gender – osteoarthritis is more common in women than in men
• Certain hereditary conditions such as defective cartilage and joint deformity
• Joint injuries caused by sports, work-related activity, or accidents
• Obesity
• Diseases that affect the structure and function of cartilage, such as rheumatoid arthritis, hemochromatosis (a metabolic disorder), Paget's disease, and gout

Signs and Symptoms of Spinal Osteoarthritis (Spondylosis)
Osteoarthritis usually begins slowly. Early in the disease, joints may ache after physical work or exercise. Often the pain of early osteoarthritis fades and then returns over time, especially if the affected joint is overused. Other symptoms may include:

• Swelling or tenderness in one or more joints, especially before or during a change in the weather
• Loss of flexibility of a joint
• Stiffness after getting out of bed
• A crunching feeling or sound of bone rubbing on bone
• Bony lumps on the joints of the fingers or the base of the thumb
• Steady or intermittent pain in a joint (although not everyone with osteoarthritis has pain)