Osteoarthritis is the most common type of arthritis. It is the type of arthritis most people are familiar with because it is most prevalent and is associated with aging. Osteoarthritis is also known by other names that are more reflective of the underlying disease process, including: “wear-and-tear” arthritis, degenerative arthritis, degenerative joint disease, and osteoarthrosis.
In a healthy person, the ends of the bones that form a joint are cushioned by cartilage, allowing for smooth, unconstrained movement of the joint. With osteoarthritis, the cartilage breaks down and deteriorates. As the cartilage deteriorates and is worn away, bone rubs on bone, resulting in pain, stiffness, and reduced mobility.
Bone spurs (also known as osteophytes) may develop which intrude on the joint space and fragments of bone may dislodge, which also interferes with normal movement of the joint. The lining of the joint, or synovium, becomes inflamed as cartilage breaks down, starting a process which itself causes even more cartilage deterioration and joint damage.
Symptoms of Osteoarthritis
Osteoarthritis can affect any joint, but the weight-bearing joints of the hips, knees, and spine are most commonly symptomatic. It is also not unusual for osteoarthritis to develop in the joints of the fingers or feet. A single joint or multiple joints may be affected by osteoarthritis.
According to the Arthritis Foundation, osteoarthritis of the knees and hips is the most common cause of arthritis-related disability in the United States. In people who have knee osteoarthritis, moderate physical activity at least three times per week can reduce the risk of arthritis-related disability by 47 percent.
Signs and symptoms associated with osteoarthritis include:
Gradual onset of symptoms
Joint stiffness in the morning, which usually lasts less than one half hour
Joint stiffness following inactivity or staying in one position for a prolonged period
Joint pain or stiffness following overuse of the affected joint
Joint pain that is typically worse in the evening than the morning
Limited range of motion in the affected joint
Joints that lock up or feel like they are giving out
Crepitus (a crackling noise)
Diagnosis and Treatment of Osteoarthritis
X-ray evidence of joint damage, a physical examination performed by your doctor, and a medical history that includes details about the onset of symptoms help diagnose osteoarthritis. Blood tests are ordered for the purpose of ruling out other types of arthritis. For example, blood test results that are abnormal in rheumatoid arthritis or other inflammatory forms of arthritis are usually normal in cases of osteoarthritis.
Though there is no cure for osteoarthritis, treatment is aimed at controlling symptoms, preserving residual joint function, and improving mobility. Medications are commonly prescribed to treat osteoarthritis (for example, NSAIDs and analgesics). Local injections of corticosteroids or viscosupplementation agents are also treatment options.
Some osteoarthritis patients find relief from topical creams or certain nutritional supplements. You may find that hot or cold packs can relieve symptoms. The benefits of exercise, physical therapy, and weight management can't be understated for controlling pain and symptoms associated with osteoarthritis. Surgery, though considered a last-resort treatment option for severe cases, can yield dramatic results.
Risk Factors and Prevalence of Osteoarthritis
Risk factors for osteoarthritis include age, gender, heredity, and obesity. Other risk factors may include previous injury, developmental abnormalities, and occupation.
Approximately 21 million Americans have been diagnosed with osteoarthritis. Though osteoarthritis can affect people of any age, it is more prevalent among older people. If x-rays were taken of everyone over seventy years old, about 70 percent would reveal x-ray evidence of osteoarthritis. Interestingly, only half of the group with x-ray evidence actually becomes symptomatic.
In general, more women than men develop osteoarthritis. However, under the age of fifty-five, more men than women are likely to develop osteoarthritis.
Obesity, because of the additional stress added to weight-bearing joints, is a risk factor for developing osteoarthritis. The knee joint is most affected by osteoarthritis in people carrying excess weight. Being mindful of the risk factors, especially those you can control such as your weight, may impact the course of your disease.
According to the CDC, weight loss of eleven pounds reduces the risk of developing knee osteoarthritis by 50 percent. One study from the Parker Institute concluded that in patients with knee osteoarthritis, weight reduction of 10 percent improved function by 28 percent.