Arthritis facts for kids

Arthritis is a medical term for when your joints become sore, stiff, or swollen. Joints are places where two bones meet, like your knees, elbows, or fingers. In arthritis, the smooth cushion between your bones, called cartilage, can wear away. This can cause bones to rub against each other, which can be painful.

Common signs of arthritis include joint pain and stiffness. You might also notice redness, warmth, or swelling around the joint. Sometimes, it becomes harder to move the affected joint. Arthritis can start slowly or appear suddenly.

There are many different kinds of arthritis. The most common types are osteoarthritis and rheumatoid arthritis. Osteoarthritis often happens as people get older and affects joints like hips and knees. Rheumatoid arthritis is a condition where your body's own defense system mistakenly attacks your joints, often in the hands and feet. Other types include gout and lupus.

Doctors often suggest resting the joint, using ice or heat, and exercising to help with arthritis. Losing weight can also help reduce stress on joints. Medications like ibuprofen can ease pain and swelling. In some serious cases, surgery might be needed to replace a damaged joint.

Arthritis is quite common, especially as people get older. It can sometimes make it hard to do daily activities or even work. The word "arthritis" comes from Greek words meaning 'joint' (arthr-) and 'inflammation' (-itis).

Signs and Symptoms

The most common symptom of arthritis is pain in your joints, which can range from mild to severe. Besides pain, you might notice other changes around your joints:

• Swelling
• Joint stiffness, especially in the morning
• Redness or warmth around the joint
• Aching in the joint
• Difficulty moving the joint or using your hand or leg
• Feeling tired or unwell (called Malaise)
• Sometimes, a rash can appear on the skin

Some types of arthritis, like lupus and rheumatoid arthritis, can affect other parts of your body too, not just the joints.

What Causes Arthritis?

The reasons why someone gets arthritis can be different depending on the type.

Osteoarthritis: Wear and Tear

Osteoarthritis often happens when the cartilage in your joints wears down over time. Think of cartilage as a smooth, slippery cushion that helps your bones glide easily. If this cushion gets damaged from an injury or just from many years of use, your bones can start to rub together. This rubbing causes pain and stiffness. It's like the natural "wear and tear" on a machine part.

Rheumatoid Arthritis: When Your Body Attacks Itself

Rheumatoid arthritis is different. It's an autoimmune disorder. This means your body's own immune system, which usually fights off germs and sickness, mistakenly attacks the healthy lining of your joints. This attack causes inflammation, swelling, and pain. It's like your body's defense system gets confused and starts fighting against itself.

Gout: Tiny Crystals

Gout is caused by too much uric acid in the body. Uric acid is a natural waste product. If there's too much, it can form tiny, sharp crystals that collect in your joints. These crystals cause sudden, severe pain, swelling, and redness, often in the big toe. Eating certain foods or drinks can sometimes increase uric acid levels.

Other Causes

There are many other types of arthritis, each with its own cause. Some can be linked to other skin conditions like psoriasis, or even infections.

Who Gets Arthritis? (Risk Factors)

Some things can make a person more likely to develop arthritis. These are called risk factors. Some you can change, and some you can't.

Things that can increase your chance of getting osteoarthritis include:

• Being overweight, as this puts more stress on joints like knees and hips.
• Having a past injury to a joint.
• The specific joint itself – some joints are more prone to it.
• Muscle strength around the joint.

For types like rheumatoid arthritis, some risk factors are:

• Being a girl or woman.
• Having family members with arthritis (it can run in families).
• Getting older.
• Past joint injuries.
• Exposure to smoking.

How Doctors Diagnose Arthritis

This image shows osteoarthritis in the index finger of a 63-year-old woman.

If you have joint pain, a doctor or health professional will examine you. They will ask about your symptoms, like when the pain started and what makes it better or worse.

To help figure out what type of arthritis you might have, doctors use different tools:

• Physical Exam: The doctor will look at your joints, check how you walk, and see if there's any swelling or tenderness.
• Imaging Tests: They might take X-rays to see the bones and joints inside your body. X-rays can show if cartilage is worn down or if bones are damaged. Other tests like CT scans or MRI scans might also be used.
• Blood Tests: Sometimes, blood tests can help identify signs of inflammation or specific markers related to certain types of arthritis, like rheumatoid factor.

Different types of arthritis can have different patterns. For example, pain from rheumatoid arthritis is often worse in the morning and lasts for more than 30 minutes. Pain from osteoarthritis might start with activity and then become more constant over time.

Understanding Osteoarthritis

This X-ray shows osteoarthritis in both knees, with the space between the bones looking narrower.

Osteoarthritis (OA) is the most common type of arthritis. It affects people and even animals like dogs and cats. It can happen in big joints like your knees, hips, and shoulders, or smaller joints like your fingers and toes. It's mainly caused by the daily wear and tear on your joints, which breaks down the cartilage. When cartilage is gone, bones rub together, causing pain.

Symptoms usually start as mild pain during activities and can get worse over time, even hurting when you're resting. OA often affects joints that carry a lot of weight, like your back, knees, and hips. It's more common in older people, with many women over 65 having some degree of OA. X-rays are key to diagnosing OA, showing things like narrowed joint space or bone spurs.

Understanding Rheumatoid Arthritis

This X-ray shows bone damage (erosions) caused by rheumatoid arthritis in a finger joint.

Rheumatoid arthritis (RA) is an autoimmune disorder where your body's immune system attacks the lining of your joints. This attack can also affect other parts of the body. RA often affects joints in the fingers, wrists, knees, and elbows, and usually appears on both sides of the body (symmetrically). If not treated, it can lead to severe changes in the shape of the joints over time.

RA usually starts earlier in life than OA, often affecting people aged 20 and older. In children, it can cause a skin rash, fever, pain, and make daily activities difficult. Early diagnosis and treatment can help many people control their symptoms and have a better quality of life.

Understanding Lupus Arthritis

This "butterfly" rash on the face is a common sign seen in people with Lupus.

Lupus is another autoimmune disorder that can cause severe arthritis. About 90% of people with Lupus experience joint pain and stiffness, similar to rheumatoid arthritis. It often affects joints in the fingers, wrists, and knees. People with Lupus might also have other symptoms like a skin rash (often shaped like a butterfly on the face), sensitivity to sunlight, hair loss, or kidney problems.

Understanding Gout

Gout most commonly affects the big toe, causing swelling, redness, and warmth.

Gout usually starts by affecting just one joint, but over time, it can affect many. It's most common in the big toe, knee, or fingers. During a "gout flare," the affected joint becomes very swollen, warm, and red, and the pain can be intense.

To manage gout, doctors might prescribe anti-inflammatory medicines during a flare. Between flares, medications can help reduce the amount of uric acid in the body. Eating a healthy diet with lots of fiber, vegetables, and whole grains, while limiting alcohol and fatty foods, is also recommended for people with gout.

There's also a less common type called pseudogout, caused by different crystals. For pseudogout, treatments focus on reducing inflammation.

Other Types of Arthritis

• Infectious Arthritis: This is a serious type of arthritis caused by bacteria that spread through the bloodstream to a joint, causing infection and damage. It needs quick diagnosis and treatment. Viruses, like the one causing COVID-19, can also sometimes lead to a type of joint inflammation called reactive arthritis.
• Psoriatic Arthritis: Some people with a skin condition called psoriasis can also develop psoriatic arthritis. They usually first have skin symptoms (like scaly, itchy patches) and then start to feel joint pain, stiffness, and swelling. There's no cure, but treatments can help manage the symptoms.

Treating Arthritis

Currently, there isn't a cure for most types of arthritis, but there are many ways to manage the symptoms and improve how your joints work. Treatment plans depend on the type of arthritis you have.

Physical Activity and Therapy

Staying active is very important! Regular, gentle exercise of the affected joints can help reduce pain in the long run. It also helps keep your joints healthy and improves your overall body strength and flexibility.

Physical therapy and occupational therapy can be very helpful. Physical therapists teach you exercises to improve joint movement, strength, and balance. Occupational therapists can help you find easier ways to do daily tasks if your joints are making things difficult. For example, they might suggest special tools or ways to hold things.

Medications

Doctors use different medicines to treat arthritis. They usually start with medicines that have fewer side effects.

• Pain Relievers: Over-the-counter medicines like acetaminophen (paracetamol) or ibuprofen can help reduce pain and swelling.
• Anti-inflammatory Drugs: For more severe inflammation, doctors might prescribe stronger anti-inflammatory medications.
• Other Medications: For conditions like rheumatoid arthritis, which involve the immune system, doctors might use special medications called disease-modifying antirheumatic drugs (DMARDs). These medicines help slow down the disease and protect your joints from further damage.

Surgery

In some serious cases, when a joint is very damaged and other treatments haven't worked, surgery might be an option. The most common surgery is joint replacement surgery, also called arthroplasty. Common joints that are replaced include the shoulder, hip, and knee. After surgery, patients can often return to many physical activities like swimming or golf.

Helpful Tools

People with arthritis, especially in their hands, might find it hard to do simple daily tasks like turning a key or opening jars. There are special tools, called adaptive equipment or assistive devices, that can help. These tools are designed to make tasks easier and less painful. Sometimes, these aids can even be made using 3-D printing to help reduce costs.

A Look Back in Time (History)

Evidence of arthritis has been found in ancient creatures like dinosaurs! The first known signs of human arthritis date back as far as 4500 BC. It was a common ailment for prehistoric people, with traces found in ancient Native American remains and even in Ötzi the Iceman, a mummy from around 3000 BC.

In 1703, William Musgrave wrote an important medical book about arthritis. Later, in France, Augustin Jacob Landré-Beauvais was the first to describe the symptoms of rheumatoid arthritis in detail.

In the 1960s, a doctor named John Charnley performed the first successful hip replacement surgery in England to treat arthritis. This was a huge step forward in treating severe joint damage.

Living with Arthritis

Arthritis is a leading cause of disability in many countries, including the United States. Millions of people with arthritis face challenges with daily activities. It can sometimes make it difficult to be physically active or even go to work. The condition can also lead to frequent doctor visits.

See also

In Spanish: Artritis para niños

• Antiarthritics
• Knee arthritis
• Osteoimmunology
• Weather pains