Different Types of Arthritis and Pain Characteristics

"Arthritis" is an umbrella term describing over 100 conditions that affect the joints and surrounding tissues. An estimated 91 million adults in the United States live with arthritis, with osteoarthritis, rheumatoid arthritis, gout, and psoriatic arthritis among the most common types.

This article discusses the differences between arthritis types, the most and least common types, and what to do if you suspect you may have arthritis. 

How Are the Types of Arthritis Different?

Each type of arthritis has unique symptoms, causes, and characteristics, but they all share one thing in common—joint inflammation and pain. The word "arthritis" literally means "joint inflammation."

While all forms of arthritis affect the joints, they all have distinct differences in how they develop, which joints are affected, and their impact on a person's overall health. 

Affected Body Parts 

Arthritis can affect any joint in the body, and some forms of the condition can affect the muscles, tendons, ligaments, eyes, and internal organs. Joints most commonly affected by arthritis include:

• Knees
• Hands
• Hips
• Lower back
• Neck
  

Each type of arthritis targets specific joints and tissues differently, influenced by factors like wear and tear due to aging or injury, inflammation, genetics, or the body's immune response. The most common types of arthritis affect different body parts, such as:

• Osteoarthritis: Also known as degenerative arthritis, this type primarily affects weight-bearing joints like the knees, hips, and spine but also commonly affects the fingers. 
• Rheumatoid arthritis (RA): RA tends to target smaller joints in the hands, wrists, and feet and can also affect the eyes, skin, blood, nerves, and internal organs, such as the heart and lungs.
• Psoriatic arthritis (PsA): PsA primarily affects joints in the spine and hips, but also the fingers, toes, and heels. PsA can also affect the skin, eyes, nails, and digestive system.  
• Gout: Primarily affects the big toe but can also attack other joints. 
  

Autoimmune Characteristics

Some types of arthritis are autoimmune diseases, meaning the body's immune system mistakes the body's cells for a foreign invader (e.g., bacteria, virus) and releases inflammatory chemicals to attack those cells. 

With rheumatoid arthritis (RA), the most common form of autoimmune arthritis, the immune system attacks the synovial membrane (the lining of the joints), leading to inflammation. Inflammation causes joint pain, swelling, and stiffness and damages the affected joints over time.

Autoimmune arthritis can also cause systemic (bodywide) inflammation that affects other body parts and systems, such as the eyes, internal organs, skin, digestive system, and blood vessels. Common types of autoimmune arthritis include:

• Rheumatoid arthritis
• Psoriatic arthritis 
• Sjögren's syndrome
• Axial spondyloarthritis
• Ankylosing spondyloarthritis 
• Juvenile idiopathic arthritis 
• Systemic lupus erythematosus 
  

Other types of arthritis do not involve the immune system but develop due to other causes, such as genetics or environmental and lifestyle factors. Osteoarthritis, for example, develops due to normal wear and tear from aging or joint injury.

Symptom Development

The development of arthritis symptoms varies, depending on the type of arthritis you have. With some forms of arthritis, symptoms develop gradually and progressively worsen as the disease progresses. Osteoarthritis, for example, is a degenerative condition that develops when the cartilage in joints breaks down slowly over time. As the cartilage wears away, the bones rub against each other, leading to pain, stiffness, and reduced joint mobility.

With other forms of arthritis, such as gout, symptoms can develop suddenly, and joint pain, stiffness, and swelling may be severe and debilitating. 

Many types of arthritis are associated with periods when symptoms worsen, called flare-ups. Flare-ups are common with autoimmune and inflammatory forms of arthritis, such as rheumatoid arthritis and psoriatic arthritis.

Stress, infection, diet, weather changes, and other lifestyle and environmental factors can lead to flare-ups.

Common Types of Arthritis

Arthritis is a leading cause of disability in the United States, affecting children and adults of all ages. The most common types of arthritis are: 

• Osteoarthritis (OA): OA is the most common form of arthritis, affecting an estimated 32.5 million adults in the United States.
• Rheumatoid arthritis (RA): RA is the most common form of autoimmune arthritis, with approximately 1.3 million adults in the United States living with RA.
• Gout: Gout is the most common form of inflammatory arthritis, affecting 8.3 million U.S. adults.
• Psoriatic arthritis (PsA): PsA is an inflammatory arthritis associated with a skin condition (psoriasis). About 2.4 million people in the United States have psoriatic arthritis.

Less Common Types of Arthritis 

Certain arthritis types are less common than others, including:

• Ankylosing spondylitis (AS): A kind of inflammatory arthritis primarily affecting the joints and ligaments of the spine. AS is a progressive disease that can cause the spinal vertebrae to fuse over time. AS is rare, affecting only 0.5% of the general population.
• Palindromic rheumatism (PR): A rare, recurrent inflammatory arthritis that causes brief episodes of severe joint pain, swelling, and redness in the hands, wrists, knees, and ankles. The episodes (palindromes) last several hours to several days and often resolve spontaneously. 
• Reactive arthritis: A form of inflammatory arthritis that develops in response to a bacterial infection—usually a urinary tract or sexually transmitted infection. Approximately 1 in 1,000 people develop reactive arthritis. 

Most Painful Types of Arthritis 

All arthritis types can cause pain. Experiences of pain are highly individual; what one person finds extremely painful may not be as severe for another. Several factors influence the severity of arthritis pain, including the severity of joint damage, frequency and duration of flare-ups, number of joints affected, and individual pain sensitivity. 

Gout is often called the most painful type of arthritis due to the sudden onset of intense, severe pain. Gout occurs when uric acid (a body waste product) builds up in the synovial fluid surrounding joints. Gout pain usually develops at night, affecting one joint at a time—usually the big toe. It is often described as excruciating or throbbing pain.

Inflammatory and autoimmune forms of arthritis, such as rheumatoid arthritis and psoriatic arthritis, are also known for causing intense, sometimes debilitating pain. These types of arthritis are associated with chronic inflammation that can affect multiple joints and cause problems with other body parts and systems. 

Undiagnosed Arthritis: Steps to Getting a Diagnosis 

Experiencing joint pain, swelling, or stiffness can be a sign of arthritis. Whether you experience joint pain that comes and goes or is constant, it's important to see a healthcare provider to discuss your symptoms. Generally, joint pain or swelling that lasts for three days or longer or pain that feels worse in the morning or after prolonged periods of sitting is a sign of arthritis.

The first step to getting a diagnosis is scheduling an appointment with a primary care physician. Be prepared to discuss your symptoms in detail during the visit, including the location, severity, and duration of pain.

Your provider will also want to know whether you have a family history of arthritis and will perform a physical examination, focusing on the affected joints and assessing their range of motion. They may order blood tests, imaging tests (e.g., X-rays, magnetic resonance imaging (MRI), or joint fluid tests to provide an accurate diagnosis.

Summary 

"Arthritis" is a general term that describes over 100 conditions affecting the joints and surrounding connective tissues. Arthritis can affect different joints throughout the body, depending on the type. All forms of arthritis involve joint pain, inflammation, or swelling; some can affect other body parts and systems.

Certain types of arthritis develop gradually over time, while others can cause sudden and severe pain. See a healthcare provider if you have joint pain or swelling to discuss your symptoms and treatment options.