Arthritis Osteoarthritis and Gout: The Top Three
There are many forms of arthritis. Arthritis means inflammation of a joint. It can be due to trauma with damage to the cartilage and bleeding into the joint. It can be due to infection, with disseminated bacteria or a puncture wound into the joint. It can be secondary to conditions like diabetes or hormonal imbalances or psoriasis. The purpose of this discussion is to discuss the three most common forms of arthritis: osteoarthritis, rheumatoid arthritis, and gouty arthritis.

Osteoarthritis is more of a deteriorative condition of the joint and bone, though certainly does have inflammation. It is manifest most often with a shrinkage and deterioration of the cartilage in the joint. The cartilage and joint fluid normally lubricates the joint and provides a cushion for the weight placed on it. With its deterioration, the subchondral bone under the cartilage begins to deteriorate and form an abnormal surface and the anatomy becomes articulation of the joint with painful bone on bone motion. Osteoarthritis is the number one cause of chronic disability in this country with over 27 million people affected. It is the number one cause for hip and knee replacement and costs the health economy billions of dollars a year. Over 25% of primary care visits are for osteoarthritis. It accounts for one-half of all non-steroidal anti-inflammatory (NSAI) prescriptions.

The typical patient with osteoarthritis comes in with knee pain, though the process can and does affect the hands, the hips, the spine, and almost any other joint. The pain gradually gets worse as the day wears on, as opposed to rheumatoid arthritis when pain is usually maximal upon arising in the morning. It is associated with decreased mobility, increased pain on cold and humid days or with weight-bearing, deformity of the joint, and sometimes a locking of the joint. If the joint is x-rayed, it shows decrease in cartilage space, subchondral bone changes, and often calcium spurs where the body has tried to repair the condition.

Treatment of osteoarthritis is usually multimodal. Patients do better with education about their condition. A first line of medication is often acetaminophen in doses of around four grams a day if the liver doesn’t object. Later, NSAI’s like the "profen" drugs can be tried if there is no history of gastrointestinal disorder. If there is a contraindication, several of these drugs come in a topical cream or gel which can be directly applied to the joint. Splinting of the joint may help, as may unloading the weight of the joint with a crutch or cane. Glucosamine and chondroitin sulfate were once touted for their benefit upon the joint, but this has been largely disproven. Some benefit may be realized with physical therapy, and to a lesser extent, with acupuncture. Sometimes the joints can be injected with corticosteroids, or the knee with hyaluronic acid to increase its fluid viscosity.

A second type of arthritis is rheumatoid arthritis. It affects about two million people, with 75% being women. It is caused by the immune system, especially cytokines, actually attacking its own joint membranes, cartilage, ligaments, and bones. It seems to have a predilection for the joints of the hands, wrists, feet, and ankles. It hurts worse in the morning and equally upon arising. It will essentially destroy the joints over time, and this is why early treatment is necessary. It is technically called an autoimmune disease. Treatment is directed at turning off a portion of the immune system, especially that which is attacking the joints. The treatment can be with drugs that generally turn off the immune system, like methotrexate, or with drugs that specifically inhibit the cytokines. Other treatments for symptoms, like NSAI’s and joint injection with corticosteroids, are much the same as with osteoarthritis.

A third type of arthritis is gout. It is caused by crystals of uric acid precipitating in the joints and soft tissues (tophi), where it sets up an inflammatory process. Gout is therefore caused by too much uric acid in the blood. Uric acid is a breakdown product of protein. Gout is caused by the body either making too much uric acid, or by the kidneys not filtering out enough. There are certain things which tend to increase uric acid: beer, red meat, and seafood. Certain drugs such as aspirin and alcohol cut down on the kidney excretion of uric acid. Although gout can occur in any joint with excruciating pain and tenderness, it has a real predilection for the right great toe.

Treatment of gout involves lowering the blood level of uric acid. The most common drug for this is allopurinol, which interferes with an enzyme process in the production of uric acid. A new drug, febuxostat, works the same way, but doesn’t have the same drawbacks and side-effects as allopurinol. It’s interesting that gout attacks can occur during treatment with these drugs because body stores of uric acid are being mobilized. These acute flare-ups can be treated with NSAI’s, colchicines, or joint injections with corticosteroids. Since elevated uric acid is an independent risk factor for heart disease, it is doubly important that uric acid levels usually above 6.8 be treated.

These are the main three types of arthritis. A tremendous amount of research is underway to discover new treatments for each of these. As each can have elements of the immune inflammatory process, several new treatments involve modulating the immune system. This is particularly true for osteoarthritis as its inflammatory characteristics have not been especially addressed. New drugs are on the horizon for all of these conditions.

John Drew Laurusonis

Doctors Medical Center

www.doctorsmedicalctr.com