Everyday activities can be greatly affected by hip arthritis symptoms, which can include limited range of motion, joint stiffness, and pain in the hip, groin, leg or back. As symptoms get worse over time, hip arthritis can greatly affect mobility and quality of life.
The most common type of hip arthritis is osteoarthritis. Inflammatory forms of arthritis—such as rheumatoid arthritis, an auto-immune disease, and gout, a metabolic disease—have similar symptoms but are less common.
Two major signs of hip osteoarthritis that can be seen on an x-ray are:
- Deterioration of the articular cartilage that covers the surfaces of the hip’s ball-and-socket
- The appearance of bone spurs, called osteophytes
The hip is the third most susceptible body part to develop osteoarthritis, after the hand and knee.1-3 Health professionals do not know the cause of hip osteoarthritis but have identified several risk factors that increase the likelihood of its development.
There is no known cure for hip osteoarthritis. With a large percentage of the American population aging, health professionals continue to grow and refine knowledge about prevention, diagnosis, and treatment options for hip osteoarthritis.
Hip Joint Anatomy
The hip is located where the head of the femur, or thighbone, fits into a rounded socket of the pelvis, called the acetabulum. This ball-and-socket construction allows the leg to move back and forth and side-to-side, as well as rotate, pointing toes inward and outward.
Both the acetabulum and the rounded femur head are lined with articular cartilage. The articular cartilage is an extremely slippery, strong, flexible material that provides a buffer between the bones as the hip flexes and bears weight.
See Hip Anatomy
How Hip Osteoarthritis Causes Pain
Hip osteoarthritis is associated with many changes in the hip that may lead to pain.
- Cartilage is damaged or wears away. The femur and pelvic bones that make up the hip’s ball-and-socket may rub and grind against one another. The bone-on-bone friction can cause hip pain.
- The bones may produce small, scalloped growths, called osteophytes or bone spurs, to compensate for the deteriorated cartilage. In turn, the bone spurs can create even more friction.
- The bone underneath the damaged cartilage can develop lesions, and these lesions are associated with pain.4
- The delicate lining that surrounds the hip joint can become inflamed. This lining, called the synovium, produces and contains joint fluid, which supplies nutrients to the joint. During osteoarthritis, the inflamed synovium becomes thicker, and the quantity and composition of the joint fluid it produces may change. This potentially painful condition5 is called synovitis.
In addition, osteoarthritis can change the hip’s mechanics, causing tendons, ligaments, and bursa to undergo excess strain and friction. Inflammation or injury of these tissues may be a painful side-effect of hip osteoarthritis.
Not everyone who has hip arthritis will experience pain. It is not clear why some people who have arthritic damage to a hip experience pain while others do not.