Is It Rheumatoid Arthritis or Osteoarthritis? The Key Differences

Lots of people experience joint pain from time to time, but different causes call for entirely different treatments. You’re probably familiar with osteoarthritis (OA) — it’s the most common type of arthritis, usually associated with getting older. And it’s very different from another, less common type, called rheumatoid arthritis (RA). By understanding the differences between the two, you can find the right specialist and get the proper treatment plan.  

What Is Actually Happening in Your Joints? 

Rheumatoid arthritis is an autoimmune disease that affects the whole body. Osteoarthritis is a degenerative condition that affects one or more specific joints.  

In RA, your immune system malfunctions and attacks your own joint tissues, including the synovial membrane that lines your joints. This leads to widespread swelling that makes the lining of the joint thicker and can eventually damage both bone and cartilage. The damage happens because the body’s cells are not communicating properly. 

Osteoarthritis is a degenerative disease that is traditionally thought to be a result of “wear and tear.” OA develops when the protective cartilage at the ends of your bones erodes, leading to changes in bone shape, including bone spurs, and triggering inflammation that causes pain, stiffness and loss of mobility. It is a mechanical issue rather than an immune system malfunction and often results from advanced age or injury. 

How Do Symptoms Differ Between RA and OA? 

Both RA and OA cause joint pain and stiffness, but while RA can come on suddenly at any age, OA develops over years and occurs more often in older adults or in a joint that has previously been injured. 

Other symptoms of RA can include fever; deep fatigue; joints that are hot and red, and it can affect other parts of the body. Severe fatigue and low-grade fevers can recur with RA, whereas OA symptoms are primarily in the affected joints.  

RA symptoms can also vary, so a person can feel pretty well one day and not be able to get out of bed the next, while OA symptoms tend to be more consistent and may progress with time and use. 

Because rheumatoid arthritis is an immune system disorder, it impacts your entire body. You can experience overwhelming fatigue, loss of appetite and low-grade fevers in addition to joint pain. In some people, inflammation also causes problems with their eyes, lungs or other organs.  

Although osteoarthritis involves inflammation, it does not circulate through your body. While chronic pain may disrupt your sleep and leave you tired, OA does not produce a systemic inflammatory response.  

People with RA often have morning stiffness that lasts more than 30 minutes, whereas stiffness from OA in the morning or after inactivity eases up within 30 minutes once you start moving around. 

Which Joints Are Affected First? 

RA typically comes with joint pain on both sides of the body — often in the smaller joints, like both hands. OA typically begins in one joint at a time, like a knee or hip. 

Rheumatoid arthritis generally mirrors itself across the body. If one wrist swells, the other will, also. This symmetrical joint involvement often, but not always, targets the smaller joints of the hands and feet first. For example, you may notice swelling in the knuckles at the base of your fingers.  

With osteoarthritis, you might develop severe pain in your right knee from an old sports injury while your left knee is unaffected. It frequently strikes weight-bearing joints, including the hips, knees and lower spine. In the hands, OA typically targets the joints in the middle of the fingers, those closest to fingertips and the base of the thumb.  

What Doctor Should I See For My Arthritis? 

If you are having joint pain that is affecting your ability to function or your quality of life, you will likely first see your primary care doctor. In some cases, that is the only doctor you’ll need, depending on your diagnosis and severity of arthritis. 

For advanced cases of osteoarthritis, your doctor may refer you to an orthopedist, or in some cases to an orthopedic surgeon. If your doctor suspects you have an autoimmune form of arthritis, like rheumatoid arthritis, then they should refer you to a rheumatologist — a specialist who treats diseases of the musculoskeletal system. 

How Do Doctors Diagnose RA and OA? 

Your doctor will perform a physical exam for both RA and OA. However, RA is diagnosed through blood tests and MRI or ultrasound imaging, whereas OA is diagnosed primarily through clinical examination and X-rays. 

To confirm rheumatoid arthritis, your doctor will ask about your medical history, including any family history of RA, and order blood tests looking for specific antibodies. The presence of rheumatoid factor or anti-cyclic citrullinated peptide (anti-CCP) antibodies can indicate rheumatoid arthritis. However, some people with blood markers never develop the disease and some with the disease have normal blood tests. Other tests check inflammatory markers in your blood, such as C-reactive protein (CRP) or erythrocyte sedimentation rate (sed rate), to measure active inflammation. Elevated markers can confirm the presence of the disease.  

Diagnosing osteoarthritis does not require blood work. Instead, your doctor will rely on a physical examination to check for joint enlargements and pain and order imaging tests such as X-rays. The X-rays can show a narrowing of the space in a joint where cartilage has eroded.  

Why Don't the Same Medications Work for Both RA and OA? 

RA requires disease-modifying drugs to suppress the immune system, which helps ease symptoms. There is no disease-modifying drug for OA, so people get relief by treating its symptoms. That includes ways to reduce joint stress, like weight loss, as well as physical therapy and pain relievers.

People with RA need specialized medications called disease-modifying antirheumatic drugs, such as targeted biologics, to halt joint destruction. These drugs work by interrupting specific parts of the immune system that cause the damage. Without these medications, the immune system continues to attack the joints, regardless of how much pain medication you take.  

Treating OA focuses on managing the mechanical stress and supporting the damaged joint to help ease pain. Your doctor may recommend targeted physical therapy to strengthen the surrounding muscles, which takes pressure off the joint. A physical or occupational therapist may also help correct your movements or posture to relieve pressure on joints. Your doctor may also suggest weight management strategies, joint injections and topical or over-the-counter pain relievers or nonsteroidal anti-inflammatory drugs to keep you moving comfortably. 

Always consult a qualified healthcare professional to get an accurate diagnosis. Early diagnosis and treatment can help protect your mobility and quality of life — and especially with RA, your overall health.