Human joints come in many shapes and sizes and allow us to move and carry out normal activities of daily living. Without joints, we would be rigid and immobile. But they are also often injured, causing pain and discomfort.
The most commonly injured joints are the knees, shoulders, ankles and spine. Approximately 30 million doctor visits a year are due to knee and shoulder injuries alone. Some 150 million to 200 million cases of back pain send people to the doctor every year—and many of those are related to joint injuries.
How do joints work?
Joints are designed to withstand the loads placed on them and provide a full range of motion. Each joint is made up of at least two surfaces that touch each other and allow for movement. These include ball-and-socket joints like the hip, hinge joints like the knee and elbow, and gliding joints like those in the spine.
The bones that make up the joint allow movement, but it is the muscles that pull the bones that produce the movement. Muscles are attached to bones by structures called tendons. Tendons must be both strong to facilitate movement and compliant to prevent damage to the muscle tissues. Ligaments, which are stiff structures that connect bones, help to prevent excessive movement.
Muscles, tendons, and ligaments are attached around each joint at very specific positions, with joint surfaces shaped in exact dimensions. Fluid within most of the joints lubricates the joint surfaces to reduce friction and allow for lifelong use.
How do I keep my joints in good shape?
The movements that you perform on a daily basis are critical to long-term joint health, as are proper nutrition, a healthy exercise regimen and a healthy lifestyle. Proper lifting is also important.
Moving a joint through its full range of motion serves several important purposes. Joints are not supplied directly with blood as are other organs within the body, so the saying “If you don’t use it, you’ll lose it” applies to joint function.
Most joints in the body are lined with cartilage—a firm but pliable tissue that covers the surfaces of the bones that make up the joint. Cartilage within a joint is nourished by synovial fluid, which is “forced” into the joint cartilage through a process called imbibition.
See Your Chiropractic Physician If you find yourself in pain despite your best efforts, your doctor of chiropractic can treat any injuries and provide additional advice.
