Medically Reviewed

Chrysoula I. Liakou

MD, PhD, Internal Medicine Specialist and
Cancer Immunology Researcher.

What Is Arthritis?

Arthritis is a condition that causes pain, swelling, and stiffness in your joints. Joints are the places in your body where two or more bones meet, like in your knees, wrists, hips, and ankles. When arthritis damages your joints, it can make moving around uncomfortable and sometimes very painful. This condition can affect people of all ages, even teenagers, but it’s most common in older adults.

There are over 100 types of arthritis, each with different causes. One common type happens as joints naturally wear down with age, which is known as osteoarthritis. Other types can develop after an injury damages a joint. Some forms of arthritis are linked to autoimmune diseases, where the immune system mistakenly attacks healthy joint tissue, like rheumatoid arthritis.

If you have joint pain that won’t go away or is affecting your ability to move or do daily activities, it’s essential to see a doctor. Early diagnosis and treatment can make a big difference in managing the symptoms and maintaining an active lifestyle.

Arthritis Symptoms

Arthritis can cause various symptoms that impact the joints and, sometimes, other body parts. These symptoms can range from mild to severe and may come and go or become long-term.

Common symptoms of arthritis include:

Pain: Can be constant or come and go, affecting one or more joints.
Swelling: The skin over the joint may become red, swollen, and warm to the touch.
Stiffness: Often worse in the morning or after periods of inactivity; can also occur after exercise.
Reduced movement: Difficulty moving the joint or doing daily activities.
Tenderness: The joint may feel sore when pressed.
Redness and warmth: Common around swollen joints.

Other symptoms that may occur, depending on the type of arthritis:

Fatigue: Feeling tired and lacking energy.
Morning stiffness: Lasting 30 minutes or more in conditions like rheumatoid arthritis.
Clicking or grating feeling: Often in the knees or joints that bend.
Joint instability: Weakness or a feeling that the joint may give way.
Low-grade fever: Especially with autoimmune forms of arthritis.
Eye inflammation: Seen in certain types, like juvenile arthritis.

Arthritis Types

Arthritis comes in many forms, with over 100 different types. Here are some of the most common ones:

Osteoarthritis (OA): This is the most common type of arthritis and happens when the cartilage cushions your joints and wears down. This causes pain, stiffness, and swelling. It usually affects the knees, hips, spine, and hands. Osteoarthritis is more common as people get older or after an injury.
Rheumatoid Arthritis (RA): RA is an autoimmune disease, which means the immune system attacks the body’s joints by mistake. This causes painful swelling, which can damage the joints over time. RA often affects the same joints on both sides of the body, like wrists or knees, and can also make you feel exhausted.
Gout: Gout causes sudden, sharp pain, often in the big toe. It happens when uric acid builds up and forms crystals in the joints. The pain can be intense and may be triggered by certain foods or drinks.
Ankylosing Spondylitis: This type of arthritis mainly affects the spine, causing pain and stiffness from the neck to the lower back. Over time, the bones in the spine can fuse, making movement difficult. It usually starts in young adults and is more common in men.
Psoriatic Arthritis: People who have the skin condition psoriasis can also get psoriatic arthritis. It causes joint pain, swelling, and stiffness, making fingers and toes look swollen. It also causes fatigue and varies in severity.
Juvenile Idiopathic Arthritis (JIA): This type affects kids under 16. It causes joint pain, swelling, and stiffness and can impact a child’s growth if not treated. JIA can come and go, but with proper care, it can improve or go into remission.
Septic Arthritis: This type is caused by a bacterial or fungal infection in a joint. It causes severe pain and swelling and needs quick treatment with antibiotics to prevent damage.

Each type of arthritis is different, and getting the proper treatment is essential for managing the symptoms and staying active.

Arthritis Causes

Arthritis can have many causes, depending on the type. Here are some common ones:

Wear and tear: This causes osteoarthritis, which happens as you age. Years of using your joints can wear down the cartilage that cushions them, leading to pain and stiffness. Injuries like fractures can also increase the risk of osteoarthritis later in life.
Immune system problems: In rheumatoid arthritis and other autoimmune conditions, the immune system mistakenly attacks healthy joint tissues. This causes swelling, pain, and joint damage. Conditions like lupus and scleroderma are also linked to autoimmune issues.
Uric acid buildup: Gout is caused by high uric acid levels in the blood. When the body has too much uric acid, sharp crystals form in the joints, leading to sudden and intense pain. Other types of crystal-related arthritis can also develop from metabolic issues.
Infections: Some types of arthritis can be triggered by infections, such as Lyme disease or viruses. These infections can cause joint inflammation and symptoms of arthritis.
Genetic factors: Certain genes can increase the risk of developing arthritis. For example, the HLA-B27 genetic marker is linked to ankylosing spondylitis.
Other risk factors: Age, family history of arthritis, obesity, smoking, and activities that involve repetitive joint movements can raise the chances of getting arthritis. Previous joint injuries also make arthritis more likely.

Sometimes, arthritis has no apparent cause and develops unpredictably.

Arthritis Diagnosis

During a video consultation, a doctor will discuss your symptoms and examine your affected joints. Afterward, they will collect all the necessary information to diagnose accurately. If the doctor needs to examine you in person to make a diagnosis, they can refer you to a surgery or hospital for further tests.

Your doctor may order a blood test to help diagnose if you have an autoimmune disease or rheumatoid arthritis. The test results can also help to identify other potential causes and determine the severity of the issue.