Arthritis: Types, Causes, Symptoms, Diagnosis and Treatment

Overview

Arthritis is a general term for conditions that cause pain, swelling and stiffness in one or more joints. It does not refer to a single disease. There are more than 100 types of arthritis and related conditions, and they have different causes, patterns and treatments.

Arthritis can affect people of any age, including children, but it becomes more common as people get older. The two most common forms are osteoarthritis, which is mainly caused by wear and tear on joint cartilage, and rheumatoid arthritis, which is an autoimmune disease. The World Health Organization estimates that around 595 million people worldwide were living with osteoarthritis in 2020 and about 18 million with rheumatoid arthritis.

Arthritis is a leading cause of pain and reduced mobility. Many types cannot be cured, but early diagnosis, the right treatment and healthy habits can control symptoms, protect the joints and keep people active.

How Joints Work

A joint is where two or more bones meet, such as the knee, hip, shoulder or finger. The ends of the bones are covered by smooth cartilage, which cushions them and allows them to glide. The joint is surrounded by a capsule lined with a thin tissue called the synovium, which produces synovial fluid to lubricate the joint. Ligaments and tendons hold the joint stable and allow movement.

Arthritis damages or inflames one or more of these structures. The result is pain, stiffness, swelling and, over time, loss of movement or changes in joint shape.

Main Types of Arthritis

Osteoarthritis (OA)

Osteoarthritis is the most common type. It occurs when cartilage gradually breaks down and the underlying bone changes. It was once thought to be simple wear and tear, but doctors now understand it as a disease of the whole joint, involving cartilage, bone, ligaments and the joint lining.

Most often affects the knees, hips, hands, spine and base of the thumb
Usually develops slowly over years
Pain tends to get worse with activity and ease with rest
Morning stiffness is usually brief, often under 30 minutes

Rheumatoid arthritis (RA)

Rheumatoid arthritis is a chronic autoimmune disease. The immune system mistakenly attacks the synovium, causing inflammation that can damage cartilage and bone.

Typically affects small joints of the hands and feet first, usually on both sides of the body
Causes prolonged morning stiffness, often lasting more than an hour
Can cause fatigue, low-grade fever and loss of appetite
Can affect organs such as the lungs, eyes, heart and blood vessels
More common in women and often starts between middle age and the sixties, though it can begin at any age

Gout

Gout is a form of inflammatory arthritis caused by a buildup of uric acid in the blood. Uric acid can form sharp crystals in a joint, triggering sudden and severe attacks.

Often starts in the big toe, but can affect ankles, knees, wrists and other joints
Attacks come on quickly, often at night, with intense pain, redness, warmth and swelling
More common in men and in people with obesity, high blood pressure, kidney disease or a diet high in red meat, seafood and alcohol
Untreated, it can lead to repeated attacks, hard lumps under the skin (tophi), joint damage and kidney stones

Psoriatic arthritis

Psoriatic arthritis affects some people who have the skin condition psoriasis, and sometimes joint symptoms appear before skin symptoms.

Can cause swollen “sausage-like” fingers or toes
Can cause nail changes such as pitting or separation from the nail bed
Can involve the spine, tendons and places where tendons attach to bone

Ankylosing spondylitis and axial spondyloarthritis

These conditions mainly affect the spine and the sacroiliac joints at the base of the spine.

Cause lower back pain and stiffness that is worse after rest and better with exercise
Often begin in young adults, commonly before age 45
In severe cases, spinal bones can fuse and reduce movement

Juvenile idiopathic arthritis (JIA)

JIA is the most common type of chronic arthritis in children, with onset before age 16. It can affect one or many joints and sometimes the eyes, so regular eye checks are important.

Septic (infectious) arthritis

Septic arthritis is an infection inside a joint, usually caused by bacteria. It causes sudden severe joint pain, swelling, warmth and often fever. It is a medical emergency, because delayed treatment can quickly destroy the joint.

Other types

Reactive arthritis: Joint inflammation that can follow certain gut, urinary or genital infections
Lupus-related arthritis: Joint inflammation as part of systemic lupus erythematosus
Post-traumatic arthritis: Arthritis that develops after a joint injury
Pseudogout (calcium pyrophosphate deposition disease): Crystal-related arthritis that can look similar to gout

Causes and Risk Factors

Causes depend on the type of arthritis. In many cases several factors work together.

Osteoarthritis

Age: Risk rises with age
Previous joint injury or repeated stress on a joint, including some jobs and sports
Excess body weight, especially for knees, and also through metabolic effects on the joints
Joint shape differences present from birth or childhood
Family history and genetic factors
Sex: More common in women, particularly after menopause

Rheumatoid arthritis and other autoimmune types

Genetic factors, including certain HLA gene variants
Smoking, which is the strongest known modifiable risk factor for RA
Sex: More common in women
Infections and other environmental triggers that may set off the disease in genetically susceptible people
Obesity

Gout

High uric acid levels from diet, genetics, kidney problems or certain medicines such as some diuretics
Alcohol, especially beer and spirits, and sugary drinks
Obesity, high blood pressure, diabetes and chronic kidney disease

Septic arthritis

Infection spreading through the blood, or entering after injury, surgery or injection
Existing joint disease, artificial joints, diabetes, a weakened immune system and intravenous drug use

Signs and Symptoms

Common symptoms of arthritis include:

Joint pain
Stiffness, especially after waking up or after sitting for a long time
Swelling around a joint
Warmth or redness over a joint
Reduced range of motion
Tenderness when touching the joint
A grating or cracking feeling (crepitus) in the joint, particularly in osteoarthritis
Weakness in the muscles around the joint

Symptoms that suggest inflammatory arthritis

Inflammatory types, such as rheumatoid arthritis, gout and psoriatic arthritis, are more likely when there is:

Morning stiffness lasting longer than 30 to 60 minutes
Swelling in several joints, especially on both sides of the body
Fatigue, fever, weight loss or feeling generally unwell
Skin rash, nail changes or red, painful eyes

When to see a doctor

See a doctor if joint pain or swelling lasts for more than a few days, keeps coming back, affects daily activities, or comes with fever, rash or fatigue. Early treatment of inflammatory arthritis, ideally within the first months of symptoms, can prevent permanent joint damage.

Seek urgent medical care if a single joint becomes suddenly hot, red, swollen and very painful, especially with fever or chills, or if you cannot move or put weight on the joint. This may be septic arthritis or a severe gout attack.

How Arthritis Is Diagnosed

A doctor, and often a rheumatologist (a specialist in joint and autoimmune disease) or an orthopedic specialist, diagnoses arthritis using several tools.

Medical history: Which joints are affected, how long symptoms last, what makes them better or worse, morning stiffness, family history and other medical conditions
Physical examination: Checking for swelling, tenderness, warmth, deformity, range of motion and signs in the skin, nails and eyes

Blood tests

Inflammation markers: ESR and CRP
Rheumatoid factor (RF) and anti-CCP antibodies: Support the diagnosis of rheumatoid arthritis
Antinuclear antibody (ANA): Looked for in conditions such as lupus
HLA-B27: Associated with spondyloarthritis
Uric acid level: Helps assess gout, though it can be normal during an attack
Complete blood count and kidney and liver tests: Used for overall assessment and before starting some medicines

Joint fluid analysis

A sample of fluid is drawn from the joint with a needle. It can show crystals (gout or pseudogout) or bacteria (septic arthritis).

Imaging

X-ray: Shows joint space narrowing, bone spurs and damage
Ultrasound: Detects inflammation, fluid and crystal deposits
MRI: Shows soft tissue, early inflammation and spinal changes
DEXA scan or CT: Used in specific situations

Because no single test confirms every type of arthritis, diagnosis depends on putting together the history, examination and test results.

Treatment Options

The goals of treatment are to relieve pain, control inflammation, protect the joints, maintain movement and improve quality of life. Treatment depends on the type of arthritis, its severity and the person’s overall health.

Treatment for osteoarthritis

There is no medicine that reverses cartilage damage, but symptoms can be well managed.

Exercise and physical therapy: The most important treatment. Strengthening, stretching, low-impact aerobic activity and balance exercises reduce pain and improve function.
Weight management: Even modest weight loss can reduce knee pain.
Pain relief: Topical anti-inflammatory gels, oral NSAIDs (non-steroidal anti-inflammatory drugs) or acetaminophen (paracetamol) as advised by a doctor
Corticosteroid injections: Can give short-term relief in some joints
Assistive devices: Walking sticks, braces, supportive footwear and splints
Surgery: Joint replacement (such as hip or knee replacement) is considered when pain and loss of function are severe and other treatments no longer help.

Treatment for rheumatoid arthritis and other inflammatory types

Starting treatment early and aiming to control the disease is the standard approach.

Conventional DMARDs (disease-modifying antirheumatic drugs): Such as methotrexate, sulfasalazine, leflunomide and hydroxychloroquine. They slow disease progression and are usually the first line.
Biologic DMARDs: Target specific parts of the immune system, such as TNF inhibitors, IL-6 inhibitors, IL-17 inhibitors, abatacept and rituximab
Targeted synthetic DMARDs: Such as JAK inhibitors
Corticosteroids: Used short-term to control flares or while other drugs take effect
NSAIDs: Help with pain and stiffness but do not stop joint damage

These medicines can affect the immune system, blood counts, liver and other organs, so regular monitoring and checks for infections such as tuberculosis and hepatitis are usually needed.

Treatment for gout

During an attack: Anti-inflammatory medicines such as NSAIDs, colchicine or corticosteroids, started as early as possible
Long-term prevention: Urate-lowering medicines such as allopurinol or febuxostat, taken regularly to keep uric acid below target levels
Lifestyle measures: Limiting alcohol (especially beer), sugary drinks and high-purine foods such as organ meats, and maintaining a healthy weight and good hydration

Treatment for septic arthritis

Septic arthritis requires urgent hospital care with antibiotics and drainage or washout of the infected joint.

Self-care and complementary measures

Rest during flares, balanced with regular gentle movement
Heat for stiff joints and cold packs for acutely swollen joints
Stretching, yoga, tai chi and swimming, which many people find helpful
Pacing activities and using joint-protection techniques
Good sleep and stress management

Supplements such as glucosamine, chondroitin and turmeric have shown mixed or limited benefit in studies. Talk to a doctor before taking any supplement, as some can interact with medicines.

Complications

Without proper treatment, arthritis can lead to:

Permanent joint damage and deformity
Loss of mobility and difficulty with daily tasks
Chronic pain and sleep problems
Depression and anxiety
In rheumatoid arthritis, an increased risk of heart disease, lung disease, osteoporosis and infections
In gout, tophi, kidney stones and kidney damage
In spondylitis, spinal stiffness and fusion

Living With Arthritis

Living well with arthritis involves ongoing partnership with a healthcare team and daily habits that protect the joints.

Stay active. Regular exercise is safe and beneficial for most people with arthritis, and avoiding movement usually worsens stiffness and weakness.
Take prescribed medicines as directed and attend follow-up appointments.
Keep a healthy weight to lessen stress on weight-bearing joints.
Do not smoke, since it increases the risk and severity of rheumatoid arthritis.
Use ergonomic tools and adapt your home or workplace if joint movement is limited.
Look after mental health. Chronic pain can affect mood, and support groups, counseling and talking with family can help.
Keep vaccines up to date, particularly if you take immune-suppressing medicines. Ask your doctor which are appropriate.

Prevention

Not all arthritis can be prevented, but some steps lower the risk or slow progression:

Maintain a healthy weight
Stay physically active throughout life
Protect joints from injury. Use proper technique and protective gear in sports and at work.
Avoid smoking
Limit alcohol and sugary drinks to reduce the risk of gout
Eat a balanced diet rich in vegetables, fruit, whole grains and healthy fats
Treat joint injuries properly and seek early care for persistent joint symptoms
Manage related conditions such as high blood pressure, diabetes and kidney disease

Common Myths About Arthritis

“Arthritis only affects older people.” Arthritis can affect children, teenagers and young adults. Rheumatoid arthritis, psoriatic arthritis, spondylitis and juvenile arthritis often start before old age.

“Exercise will wear out my joints.” Appropriate exercise strengthens the muscles that support joints and usually reduces pain. Staying inactive tends to make arthritis worse.

“Cracking your knuckles causes arthritis.” Studies have not found that knuckle cracking causes arthritis.

“Weather causes arthritis.” Some people feel more pain in certain weather, but weather does not cause arthritis.

“Arthritis is just a normal part of aging, so nothing can be done.” Many treatments can reduce pain and protect function at any age.

“Gout is caused only by eating rich food.” Diet matters, but genetics, kidney function, medicines and other health conditions also play major roles.

“There is a miracle cure.” No supplement, diet or device cures arthritis. Be cautious of products that promise a complete cure.

Frequently Asked Questions

What is the difference between osteoarthritis and rheumatoid arthritis?

Osteoarthritis is mainly caused by breakdown of joint cartilage over time and tends to be worse after activity. Rheumatoid arthritis is an autoimmune disease in which the immune system attacks the joint lining, causing inflammation, long morning stiffness and often involvement of both sides of the body.

Can arthritis be cured?

Most types of arthritis cannot be fully cured, but they can be controlled. Rheumatoid arthritis can go into remission with early, effective treatment. Gout can be effectively controlled with long-term medicine and lifestyle changes. Infectious arthritis can be cured with prompt treatment.

Is arthritis hereditary?

Genes can increase the risk of several types, including rheumatoid arthritis, osteoarthritis, ankylosing spondylitis and gout. Having a relative with arthritis raises your risk, but it does not mean you will definitely develop it.

Which doctor should I see for arthritis?

Start with a general doctor. They may refer you to a rheumatologist for inflammatory or autoimmune arthritis, or to an orthopedic specialist for joint damage and surgery.

Does diet affect arthritis?

Diet can matter, especially for gout and for body weight. No single diet treats all arthritis, but a balanced, Mediterranean-style eating pattern is generally healthy for joints and the heart.

Is it safe to exercise with arthritis?

For most people, yes. Low-impact activities such as walking, swimming, cycling and strengthening exercises are usually recommended. A doctor or physical therapist can advise on what is suitable, especially during a flare.

Can children get arthritis?

Yes. Juvenile idiopathic arthritis affects children and teenagers. Prompt treatment helps prevent joint damage and growth problems.

Are painkillers safe to take long term?

It depends on the medicine and the person. NSAIDs can cause stomach, kidney and cardiovascular problems in some people. Always use them as directed and discuss long-term use with a doctor.

Sources and Further Reading

Medical Disclaimer

This article is for general educational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Arthritis care depends on the individual, so always talk to a qualified healthcare professional about your own symptoms, test results and treatment choices. If you have a suddenly hot, swollen, painful joint with fever, or any other medical emergency, contact your local emergency services or seek urgent care immediately.