Arthritis refers to a wide range of conditions that includes over 100 types of diseases. The term “arthritis” is a synonym for “joint inflammation.” Inflammation refers to your body’s natural response to injury or disease. It can cause swelling, pain, stiffness, and other symptoms. Tissue damage can occur when inflammation persists for a long time or returns, such as arthritis.
A joint is the place where two or more bones join together, such as the hip and knee.
Cartilage is a smooth, spongy substance that covers the bones of your joints. It cushions the bones, and allows the joint’s movement without pain.
The synovium lines the joint. The synovium’s inner lining creates a slippery fluid, called synovial fluid. This fluid nourishes the joint while limiting friction.
It is covered by a fibrous capsule called the joint capsule. Ligaments, which are strong bands of tissue that connect bones and keep them stable, are called the joint capsule. Muscles, tendons and ligaments support your joints and allow for movement.
Types of Arthritis
Osteoarthritis is characterized by the degeneration of cartilage, which often occurs with age. Degenerative joint disease is also sometimes used to describe osteoarthritis. It can start much earlier if there are other causes. Arthritis can be caused by an athletic injury such as a torn anterior cruciate ligament (ACL), or a bone fracture. Although it can occur in any joint, most commonly, arthritis affects the hands, weight-bearing joints, such as the hip, knee, and facet joints (in your spine).
Rheumatoid arthritis. Rheumatoid arthritis is a long-lasting condition that can affect any joint in the body, but it most commonly affects the hands, wrists and knees. The immune system, which is the body’s defense against disease, mistakenly attacks joints and causes swelling. The inflammation can spread to other tissues, causing damage to cartilage and bone. Rheumatoid arthritis can also affect the skin, eyes and nerves in more severe cases.
Gout is a condition where the body cannot get rid of a natural substance called Uric acid. Excess uric acid can form needle-like crystals in joints, which cause severe inflammation and swelling. Gout typically affects the wrist, big toe, and knee joints.
What Causes Arthritis?
Many types of arthritis are not understood. Researchers are investigating the role of lifestyle and genetics in arthritis development.
You may be at increased risk of developing arthritis from several factors, such as:
- Age: Your joints can become worn over time. As we age, our risk of developing arthritis, particularly osteoarthritis, increases.
- Sex: Except for gout, most types of arthritis are more common in women.
- Genes: Some types of arthritis are passed down through families. Certain genes are associated with certain conditions, such as rheumatoid, Lupus, and ankylosing Spondylitis.