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OSTEOARTHROSIS (OSTEOARTHRITIS)
A CASE OF DYSFUNCTIONAL CARTILAGE
OSTEOARTHROSIS IS BY FAR THE MOST COMMON arthritic disease, with some sixteen million people seeking treatment every year and many more suffering in silence.1 The U.S. Centers for Disease Control estimates that one in five adults will experience symptoms of osteoarthrosis by the year 2020. The term osteoarthritis (the old name for this condition) is more than a little misleading. As we have seen, the Greek suffix itis means âinflammation.â But inflammation is a key symptom of rheumatoid arthritis and related diseasesânot of osteoarthrosis. The new medical term, osteoarthrosis, means âboneâjoint disorder.â This new term better reflects the nature of the disease, whose primary cause of pain is the gradual decay of cartilage and subchondral boneânot the inflammation associated with rheumatic diseases (see Chapter 6).
Osteoarthrosis is not life threatening, but it can be quite disabling if left untreated. In severe cases, joint replacement surgery may become necessary. As weâll see, however, many people with osteoarthrosis may be able to avoid surgery and chronic pain with the help of physical therapies (see Chapter 2) and breakthrough nutritional treatments (see Chapter 4).
DEFINING THE DISEASE
The term osteoarthrosis describes the typical progression of events that occurs in joints affected by any of five factors, which include normal aging, physical injury, chronic joint stress, oxidative stress (free radicals from subchondral immune cells), and genetic defects. It is helpful to understand and visualize what is going on inside a joint afflicted by osteoarthrosis. Often, the first event is some sort of injury or malfunction in articular cartilage and subchondral bone. But these events may be precipitated by problems in the synovial membrane or fluid or in peripheral joint tissuesâthe bursa, tendons, or ligaments.
Joints are marvelous biomechanical systems whose health is maintained by a sophisticated chemical feedback loop. Problems in any part of the joint can produce a domino effect that throws the whole system out of kilter. As we age, this remarkably resilient system loses its ability to absorb stresses it handles easily at earlier stages in life. Once the system is thrown out of balance, several problems may result.
- Cartilage will roughen, fray, develop ulcers, and allow joint fluid to leak into subchondral bone, causing cysts to form in the marrow.
- Subchondral bone (that is, bone to which cartilage is attached) may develop tiny fractures, sprout jagged spurs, form calluses, and harden.
- Synovial cells may begin to form tiny pellets of bone and connective tissue called osteophytes. These collect in synovial fluid and peripheral areas of the joint, causing further damage.
- Synovial membranes thicken, reducing the joint space.
- In later stages, inflammation occurs in the synovial membrane, causing cartilage cells (chondrocytes) to manufacture the wrong kind of collagen (Types I and III, instead of the normal Type II).
This troubling picture reflects a finely tuned biochemical system that has spun out of control.
Weight-bearing joints are the ones most susceptible to osteoarthrosis, which often crops up in knees and hips as well as spinal joints. The major exceptions to this rule are ankle joints, which are rarely affected, and finger joints, which, even though they are not weight bearing, are commonly afflicted. It is also unusual to find osteoarthrosis in elbows, shoulders, or wrists.
PRIMARY OSTEOARTHROSIS
When the cause of damage is unknownâand clearly not a side effect of rheumatoid arthritisâthe condition is called âprimary osteoarthrosis.â Throughout this book, we will follow standard practice and use the terms primary osteoarthrosis and osteoarthrosis interchangeably.
SECONDARY OSTEOARTHROSIS
When joint damage results from an injury, infection, gout (see Chapter 5), or rheumatic disease (see Chapter 6), the term secondary osteoarthrosis is used. The symptoms of secondary osteoarthrosis are often similar to those of primary osteoarthrosis, and blood tests are often needed to confirm the diagnosis.
SYMPTOMS OF OSTEOARTHROSIS
While almost everyone experiences some joint degeneration by middle age, symptoms rarely occur that soon. Because osteoarthrosis is a gradual degenerative condition, it may progress for years before making its presence felt. Nine out of ten people more than 40 years of age show early signs of osteoarthrosis on X rays but it may be a decade or more before any discomfort is felt.
The joint pain and stiffness caused by osteoarthrosis often starts as a minor annoyance. Typically, the first symptom is morning stiffness in one or more joints, which fades in a half hour or less. Stress on affected joints can cause pain, and range of motion may become diminished. Affected joints can stiffen into a bent position, feel tender, and become difficult to fully flex without pain. In some cases, including secondary osteoarthrosis caused by gout or rheumatoid arthritis, symptoms may flare suddenly and then recede for a time.
Later, arthritic joint(s) may begin to grate, crackle, and vibrate because degenerated cartilage no longer smooths the passage of bone over bone. Bony, pelletlike osteophytes may begin to block the motion of the joint. Fluid may build up, and the joint begins to swell and distort. These distortions start to stretch anchoring ligaments, causing the joint to loosen, destabilize, and produce pain. If pain discourages movement of the joint, muscles will begin to atrophy from lack of use, further destabilizing the joint.
DIAGNOSIS OF OSTEOARTHROSIS
While early signs may appear on X rays, a diagnosis of osteoarthrosis begins with the presence of symptoms perceptible to the patient. At that time, the doctorâs chief concern is to differentiate primary osteoarthrosis from serious rheumatic diseases. Lab tests are useful in narrowing the diagnosis to primary osteoarthrosis (see Chapter 6).
SURGICAL OPTIONS
Should the various physical and pharmaceutical therapies described in later chapters fail to prevent crippling damage, there are surgical options. While none of these procedures is risk free or guaranteed to provide permanent relief, skilled surgery often restores disabled joints to nearly normal functioning for many years.
Arthroplasty, or joint replacement surgery, involves replacement of an injured joint component or whole joint with a man-made substitute. Most operations involve the hip or knee, but arthroplasty can also be performed on joints in the elbows, wrists, fingers, ankles, toes, shoulders, and jaw. Arthroscopy employs a long, thin tool (arthroscope) with fiber-optic capacity to examine the inside of a joint and remove bony fragments. Osteoplasty is the replacement of lost bone tissue, reconstruction of defective bony parts, and removal of bony fragments. Osteotomy is designed to alter the way bones fit in the joint by removing or adding wedges of bone. Arthrodesis immobilizes a joint so that the bones will grow together. This last-resort procedure prevents movement and attendant pain by permanently fusing the joint.
WHAT CAUSES OSTEOARTHROSIS?
Some cases of osteoarthrosis are believed to be initiated by injuries to joints, but any upset in the chemical system that maintains articular cartilage and bone can start a downward spiral of joint degradation and deformity. The disruption may begin with a bone defect, traumatic injury, nerve disorder, repetitive motion injury, or genetic defect. In most cases of osteoarthrosis, no precise cause can be determined. The body can usually repair minor insults to healthy cartilage, but this capacity can be foiled by genetic flaws and significant injury to or chronic stress on joints.
GENETIC FACTORS
In younger people (40 to 60 years old), osteoarthrosis often occurs in the absence of any significant injury or chronic stress to the affected joint. Many scientists have suspected that genetics is responsible for some of these âprematureâ cases. The genetic theory gained more support in 1996 with the publication of two reports from Britain. The first study revealed that when one of two identical twins was diagnosed with osteoarthrosis, the other was significantly more likely than the general population to have it as well. The second study found that the tissue changes typical of osteoarthrosis were more similar in identical twins than fraternal twins. (Identical twins possess the same set of genes, while fraternal twins have about half in common.)2
If the hereditary hypothesis is confirmed, doctors may then be able to identify the responsible genetic trait. This could allow appropriate treatment to begin before serious damage to cartilage takes place. In Chapter 4, we will review the problems these genetic traits may cause and novel dietary supplements that can limit pain by partly restoring the resiliency of cartilage.
OXIDATIVE STRESS
There is another hypothesisâexcess oxidative stressâthat would explain why antioxidant supplements can produce improvement in osteoarthrosis. How could oxidative stress be a factor in accelerating and worsening osteoarthrosis? You will recall that cartilage contains no blood vessels and that chondrocytes (cartilage-building cells) rely on nutrients supplied from blood vessels in subchondral bone. Changes in cartilage produced by any causeâaging, genetics, inactivity, chronic stress on cartilage, or injuryâtend to reduce the blood and oxygen supply. And, ironically, cells are at greatest risk of oxidative damage when their supply of oxygen is insufficient.3 This would help explain why antioxidant supplements produce documented benefits in osteoarthrosisâa condition that is not traditionally linked to oxidative stress.
WHO IS MOST AT RISK?
Rates of osteoarthrosis are about equal in men and women, but men tend to show symptoms earlier. Hereditary traits can cause osteoarthrosis to crop up in multiple joints or produce unique symptoms, but they are relatively uncommon. Physical activities that place repeated stress on particular joints sharply raise the risk of osteoarthrosis. Risky activities include constant kneeling, lifting, typing, and bending or a regular practice of walking or jogging on hard roads or interior surfaces in poorly cushioned shoes. âCarpenterâs kneeâ is a perfect example of osteoarthrosis caused by repetitive stress.
Nevertheless, concern about osteoarthrosis developing as the result of a regular running routine may be unwarranted. The available evidence suggests that dedicated runners are not more likely to get osteoarthrosis in their hips or knees. As insurance, wear running shoes with ample support and cushioning and try to run on an athletic track or some other reasonably level, yielding surfaceânot on pavement.
Obesity was recently confirmed as a leading risk factor for osteoarthrosis in the knees. In a two-year study of women with osteoarthrosis in one knee, researchers found that those who were not obese or who lost ten pounds or more were significantly less likely to show signs of osteoarthrosis in the second knee. Participants who saw the greatest reduction in risk were the heaviest women who achieved the greatest weight loss.4
PHYSICAL AND MENTAL THERAPIES
WORKING MIND AND BODY TO REDUCE DRUG DEPENDENCY
PILLS AND POTIONS ARE NOT EVERYTHINGâyour own actions and attitudes can have dramatic impacts on symptoms and can even affect the course of your disease. Physical therapy can be highly effective in improving strength and energy while also minimizing pain. Psychological therapies and techniques can alleviate pain and enhance the performance of your immune system. Let us take a look at the available options.
EXERCISE, PHYSICAL THERAPIES, AND ACUPUNCTURE
The pain of arthritis has an insidious side effect. People suffering pain in a joint naturally want to avoid using it. When they do, the muscles and connective tissues surrounding and supporting the joint wither, contract, and weaken. Disuse causes the joint to become progressively unstable and deformed, causing more pain. This vicious cycle can end in serious incapacitation and can dim prospects for successful joint replacement surgery. In addition, incapacitation of a knee or hip joint can keep you from getting the sort of exercise necessary for good health, immunity, and vitality.
Exercise and various physical therapies have three purposes: to maintain the flexibility, stability, and strength of joint support structures; to promote overall health; and to prevent obesity or undue weight loss. Because effective physical therapy must be customized to individual circumstances, we will outline the var...