Are you wondering if the pain and stiffness in your hips, knees, or fingers are caused by arthritis? Here's how you and your doctor can decide.

Hardly anyone escapes the annoyance of occasional aches and pains, especially as we age. But persistent joint pain and stiffness can be signs of arthritis, which affects about 50 million American adults.

So how do you know if your symptoms are caused by arthritis or something else? While joint pain and stiffness are the most common terms used to describe arthritis pain, the warning signs are pretty specific. Here's what you need to know in order to get the right diagnosis — and the best treatment.

Read more: What Arthritis Pain Feels Like

Overweight and obese adults suffering from knee osteoarthritis may benefit more from combined intensive diet and exercise regimes, rather than undertaking diet or exercise regimes separately, according to a study published in JAMA.

Osteoarthritis (OA) is a common degenerative joint disease and the most common form of arthritis. Knee OA is the most common cause of mobility dependency and diminished quality of life, and obesity is a major contributing factor to the disorder.

According to the Centers for Disease Control and Prevention (CDC), two in every three people who are obese will develop knee OA in their lifetime.

Read more: Knee Arthritis Improved by Combined Diet and Exercise

Psoriatic arthritis is a chronic condition in which the immune system attacks the body, causing joint pain and other symptoms. It tends to develop in people with psoriasis.

"The most important thing for these patients is early recognition, diagnosis, and treatment of the disease," says Elaine Husni, MD, vice chair of the Department of Rheumatic and Immunologic Diseases at the Cleveland Clinic.

Many symptoms mimic other conditions or arthritis types, so psoriatic arthritis can be missed or misdiagnosed.

Read more: Psoriatic arthritis Symptoms

One of the more common shoulder conditions Midwest Orthopaedics at Rush (MOR) physicians treat is pain from arthritis of the shoulders. Shoulder arthritis is not as prevalent as hip and knee arthritis, but it is relatively common. It typically affects patients over 50.

Critical to the elimination of pain and restoration of function is a specific and appropriate diagnosis. MOR physicians have significant experience and clinical expertise in diagnosing and treating shoulder arthritic conditions. The physicians at MOR are ranked by U.S.News & World Report as the top Orthopedic group in Illinois and among the top in the country. The MOR shoulder physicians place significant emphasis on identifying a specific pain generator and developing an individualized treatment plan for each patient.

Read more: Shoulder Arthritis

Osteoarthritis is a condition that affects the joints, it's the most common form of arthritis in the UK according to the NHS and around 1 million people see there GP about it every year.

Read more: 7 ways to treat hip arthritis