woman with knee joint pain

Healthy Joints

Healthy joints allow us to keep pace with our busy day comfortably and pain-free. But when aches and pains or sudden injuries slow us down, it’s good to have some basic knowledge about how the body responds to injury and where to find expert medical advice.

synovial joint diagram

Structure of a Joint

A joint is a junction where bones are joined together, allowing the human body to be strong yet flexible. Ligaments connect bone to bone while tendons attach the bones to powerful muscles that provide strength and movement.

There are three types of joints; fibrous joints like the sutures of the skull, cartilaginous joints found between the vertebrae of the spine, and synovial joints that allow for the most movement and are found in the arms, legs, shoulders, and hips.

The synovial joints are the most prevalent, and also the most prone to injury or to damage from the wear and tear of everyday use. Some function like a hinge, flexing in one direction (fingers, toes, elbows, and knees), while others are “ball-and-socket” joints (shoulders and hips) that allow for rotational movement.

Most joints of these types are surrounded by a joint capsule lined with a synovial membrane that secretes fluid. Synovial fluid lubricates the cartilage “caps” that cover bone surfaces.

Joint Damage

Our body’s instantaneous response to a joint injury is to increase production of fluid inside the joint capsule. This results in stiffness and immobility and allows the body time to heal itself. Health experts at WebMD.com advise that an injured joint should be protected with a bandage and rested while applying ice.

The most common disease of the joints, and a leading cause of disability in America, is arthritis. Arthritis literally means “inflammation of the joint.” There are many different types and causes but the two most common are osteoarthritis and rheumatoid arthritis:

osteoarthritis info chart

Osteoarthritis occurs from overuse or wearing down of a joint. This happens naturally with age and could be influenced by diet and exercise and treated with pain relievers and topical medications.

rheumatoid arthritis info chart

Rheumatoid Arthritis is a painful disease of the joints that occurs when the immune system malfunctions and sends chemical substances that break down healthy joint tissue. Over time, bones begin to erode and the joint becomes misshaped and immobile.

Arthritis.org is an invaluable resource for information about the symptoms of arthritis, treatment options, diet and exercise advice, and ways to get involved in your local community.