Arthritis means ‘inflammation of the joints’ and is a term that encompasses a range of joint diseases and conditions, each with unique characteristics and treatment approaches. Among these, Osteoarthritis (OA) and Rheumatoid Arthritis (RA) are two of the most common types. 

Despite sharing the name ‘arthritis,’ OA and RA are very different and understanding each of these conditions is crucial for proper diagnosis and management. Below we have looked into Osteoarthritis and Rheumatoid Arthritis in more detail, highlighting the key differences between causes, symptoms and diagnosis. 

What is Osteoarthritis?

Osteoarthritis is the most common form of arthritis. It’s often associated with ageing, but can also occur after injury and is primarily caused by the breakdown and wearing away of the protective cartilage that cushions the joints, causing bones to rub together. This degeneration leads to pain, swelling and difficulty moving the joint. While OA can affect any joint, it is typically diagnosed in the knees, hips, lower back and hands.

What is Rheumatoid Arthritis?

Rheumatoid arthritis is an autoimmune condition where the immune system attacks the body’s tissues. By mistakenly attacking the soft tissue that lines your joints and provides cushioning, medically known as the synovium, RA can cause inflammation. Joint inflammation leads to pain and stiffness, and can eventually destroy the cartilage and bone within the joint. RA typically affects both sides of the body and impacts small joints first. Since RA is a systemic disease, it doesn’t just affect the joints. Over time, it can also impact other areas of the body, including the organs. 

Symptoms of Osteoarthritis and Rheumatoid Arthritis

These two types of arthritis share many of the same symptoms, which can make it difficult to differentiate between them. The symptoms often develop gradually, they can come and go, and even change over time. It isn’t uncommon for symptoms to vary in severity depending on factors like the time of day and activity levels too. Commonly, people will experience: 

  • Joint pain
  • Joint stiffness 
  • Joint tenderness
  • Joint swelling

However, there are some additional symptoms of rheumatoid arthritis to look out for. It isn’t uncommon for people living with rheumatoid arthritis to also experience fatigue and they will lack energy. Some will also have flu-like symptoms, including a high temperature, lack of appetite and muscle pains. If RA starts to affect other parts of the body, people can also experience chest pain or dry eyes. 

Causes of Osteoarthritis

Osteoarthritis is often referred to as a “wear and tear” disease because it is commonly associated with the ageing process and the gradual degeneration of joint cartilage. However, several other factors can contribute to the development of OA:

  • Joint Injury or Overuse – Injuries to joints, such as sports injuries, can increase the risk of OA. Similarly, repeated stress on a joint can increase the breakdown of cartilage.
  • Weight – Excess body weight can put more stress on weight-bearing joints, like the knees and hips. 
  • Medical Conditions – Some diseases can damage the bones and joints, which can lead to secondary OA.
  • Genetics – Some people inherit a risk of developing OA. If your family has a history of arthritis, you may be more likely to get it.

Causes of Rheumatoid Arthritis

Rheumatoid arthritis is an autoimmune disease, the exact cause of which is not fully known. However, a combination of genetic and environmental factors is believed to play a role, and increase the risk. Factors that may contribute to someone developing RA include: 

  • Genetics – Specific genes can indicate an increased susceptibility of RA, yet not everyone with the gene will develop this condition. If someone in your family has RA, this doesn’t mean that you are guaranteed to develop it too. 
  • Hormones – Since RA is more common in women than men, it is thought that hormones could potentially have a role to play in the immune system attacking parts of the body. 
  • Environmental Exposures – Some environmental factors could increase the risk of developing RA. Exposure to a virus or infection, or a traumatic or stressful episode could have a role to play in this disease. 
  • Smoking – There is evidence that smoking tobacco cigarettes increases the risk of developing RA and can make this disease more aggressive. 

Getting the Right Diagnosis 

It can be easy to confuse OA and RA, and if you’re experiencing joint pain, it’s important to speak to a medical professional. Early diagnosis is key to getting the right treatments and learning how to manage your condition. 

There isn’t a single, definitive test for RA, which is why it will ultimately be diagnosed by a specialist. However, if you think you may have RA, the first step is to see your GP. They will talk to you about your symptoms, examine your joints and run some blood tests. If they suspect RA they will then refer you to a rheumatologist, who will decide whether or not to diagnose you with RA based on the blood test results, scans, discussion and examination of the joints.

  • Physical Examination – A GP or rheumatologist will conduct an examination and check for swollen joints and muscle strength. 
  • Blood Tests – Your blood can be tested for inflammatory markers and antibodies like Rheumatoid Factor (RF) and Anti-Cyclic Citrullinated Peptide (anti-CCP).
  • Imaging Tests – Sometimes, X-rays, ultrasounds and MRI scans will be used to look for joint damage and inflammation. 

Getting Support with Rheumatoid Arthritis

In the battle against arthritis, knowledge and awareness are your best allies. Hopefully, you will now know more about the differences between osteoarthritis and rheumatoid arthritis. If you’re worried about joint pain and you think you may be suffering from arthritis, don’t hesitate to book an appointment with your GP. Early diagnosis and appropriate treatment can help manage your symptoms and improve your quality of life. 

We can provide you with lots of useful information about RA. As a patient-led organisation, we are passionate about helping people with RA and their families. You can sign up for our newsletter to receive useful information straight to your inbox.