Overview
Many diseases and conditions affect the bones and joints, yet
the treatment of these diseases and conditions with complementary and alternative
medicine (CAM) has yet to be evaluated extensively by clinical studies; thus,
variability of results among studies is typical.
“Arthritis” is the general term for joint inflammation and is
the primary distinguishing feature of joint disorders. CAM seeks to reduce
inflammation regardless of the cause of arthritis. Osteoarthritis, also known as degenerative joint disease, is
the most common disorder involving joint movement. Not limited to old age,
osteoarthritis can result from a complex interaction of mechanical, biological, or
genetic factors that result in the depletion of joint cartilage. Rheumatoid
arthritis is an autoimmune disease in which the
immune
system attacks the tissues surrounding and cushioning the
joint, eventually affecting the cartilage and bones of the joints. Gout and
bursitis also affect the joint.
Some diseases affecting the joint also affect other tissues and organs. These
diseases include systemic lupus erythematosus, fibromyalgia, and ankylosing
spondylitis. Another disorder, osteoporosis, is the decrease
in density of many different bones of the body and does not affect the joint.
Osteoporosis is often confused with osteoarthritis, yet they are very different
medical conditions with little in common.
Osteoarthritis
Osteoarthritis (OA) is distinguished by degeneration of joint cartilage and
adjacent bone, leading to pain, difficulty in movement, and stiffness. OA can
affect any joints in the body, including knees, hips, shoulders, vertebrae,
fingers, toes, and the temporomandibular joint, which is in the jaw. Standard
treatments consist of exercise or physical therapy programs, analgesic
drugs or corticosteroids for pain, and, as a last resort, joint
replacement surgery.
None of the standard treatments regenerate lost or damaged cartilage.
Cartilage is composed of collagen and proteoglycan. Collagen
is a large fibrous protein, whereas proteoglycan consists of a core protein with
linkages to many long-chain carbohydrates known as glycosaminoglycans. Chondroitin
sulfate is the glycosaminoglycan found in collagen. Because chondroitin sulfate is
an integral part of collagen, and glucosamine is an essential metabolic
intermediate in the formation of collagen, it was reasoned that providing these
compounds to persons with joint disorders would serve as a stimulus for the
formation of collagen.
Considerable research has been reported on the effectiveness of glucosamine and
chondroitin sulfate in halting and reversing joint degeneration. Although earlier
research did indeed seem to show effectiveness, there were some questions about
research design and methodology. Recent studies were more rigorous in nature,
involving larger numbers of persons and using the gold standard of clinical
trials: randomized, double-blind, and placebo-controlled
trials. Meta-analyses compile the data from many studies for
overall statistical analyses. In the case of glucosamine and chondroitin, recent
analyses do not support much benefit from their use.
A review article in 1998 reported on studies that evaluated the effectiveness of glucosamine and chondroitin sulfate in reducing pain symptoms in OA. Most studies showed that persons receiving glucosamine had a reduction in pain score, compared with those receiving placebo. Fewer studies were reported on the effectiveness of chondroitin sulfate, but the compound appeared to produce what were called favorable outcomes. An analysis reported in 2003 found that glucosamine was significant in alleviating pain and in maintaining cartilage, while chondroitin was effective in some indices of pain reduction.
Another review in 2008 studied the results of twenty-five randomized controlled studies involving 4,963 persons. When all studies (including older studies) were analyzed, glucosamine improved pain more than did a placebo after six months. When the analysis was restricted to higher-quality studies with adequate blinding (in which neither the persons studied nor the researchers knew the identity of the treatments), no benefit was observed.
A meta-analysis was reported in 2007 on twenty trials
evaluating the effectiveness of chondroitin sulfate for reducing symptoms of OA.
Heterogeneity among the trials made analysis difficult, but when only large,
methodologically sound trials were included in the analysis, no significant
benefits of chondroitin were found.
A two-year study reported in 2006 evaluated the effectiveness of glucosamine and chondroitin sulfate on slowing structural damage of knee OA. Measurements of joint space width (cartilage depletion) were used as measures of structural damage. At the two-year stage of treatment, no statistical differences were found among the treatments, compared with the placebo control. The combination of glucosamine and chondroitin may be less active, compared with their individual effects. Persons with less severe OA at the beginning of the study tended to show less joint loss than those using a placebo.
A large glucosamine/chondroitin arthritis intervention trial (GAIT) involved 1,583 persons. After twenty-four weeks of treatment, glucosamine or chondroitin singly or in combination did not show the significant 20 percent reductions in knee pain, compared with placebo, although the groups did show numerical improvements over placebo. A subgroup of persons with moderate to severe pain at the beginning of the study showed a significant reduction in pain, compared with placebo.
A companion GAIT trial studied the effect of glucosamine and chondroitin singly or in combination on progressive loss of joint space width (JSW). At two years, no treatment achieved statistically significant differences in JSW loss, compared with placebo, although the placebo had less JSW loss than anticipated.
Rheumatoid Arthritis
Rheumatoid arthritis (RA) is an autoimmune disorder in which the immune
system attacks the tissues lining the joints, causing swelling, pain, and
stiffness. Rheumatoid arthritis can eventually affect the bones and cartilage in
the joints.
CAM seeks to alleviate the symptoms of rheumatoid arthritis without attempting cures for the underlying causes. Mind/body techniques, such as relaxation, imagery, and biofeedback, can improve symptoms such as pain, psychological state, physical function, and ability to cope. In terms of dietary supplements, some clinical studies have shown that omega-3 fatty acids may be beneficial in reducing the inflammation of rheumatoid arthritis. Preliminary evidence suggests that gamma linolenic acid can have the same effect.
Tai
Chi is a traditional martial art that combines slow and
gentle movements with mental focus. A twelve-week study showed that Tai Chi
improved muscle function in lower limbs in persons with RA. Persons using Tai Chi
experienced improved psychosocial benefits such as less pain and improved posture,
balance, and coordination.
Other Joint Diseases and Conditions
Gout. Gout is a recurrent, acute inflammation
of peripheral joints, such as the big toe, instep, ankle, knee, wrist, and elbow.
The condition is caused by deposits of monosodium urate crystals in cartilage,
tendons, and ligaments and can become chronic with joint deformities. CAM focuses
on the diet and includes recommendations such as avoiding foods with high purine
content (such as beef, organ meats, sardines, and anchovies), eating cherries,
taking fish oil supplements, minimizing alcohol consumption, and drinking eight
glasses of water per day.
Systemic lupus erythematosus. Systemic lupus erythematosus
(SLE) is an autoimmune disease in which antibodies
attack connective tissue cells. Connective tissue serves to support and connect
organs, muscles, joints, and other body parts. Because connective tissue is
widespread, the organs affected and symptoms observed are also broad. The vast
majority of persons with SLE experience joint pain and swelling.
A few studies have indicated that dehydroepiandiosterone (DHEA) may lead to decreased symptoms of lupus. Persons with lupus have abnormally high levels of estrogen metabolites and low levels of testosterone. DHEA may control these hormone abnormalities and may have effects on immune system components, such as a decrease in pro-inflammatory cytokines. Preliminary studies have also indicated a beneficial effect of omega-3 fatty acids in fish oils on reducing abnormal levels of the immune components cytokine and interleukin.
Fibromyalgia. Fibromyalgia (FM), or fibromyalgia
syndrome, is a disorder characterized by chronic pain, tenderness, and stiffness
in soft tissues, including muscles, tendons, and ligaments. FM most commonly
affects women, and its cause is unknown. Some believe the disorder is triggered by
physical or mental stress. Other symptoms of the disorder include severe fatigue,
nonrestorative sleep, irritable bowel syndrome,
depression, and cognitive difficulty (also called brain
fog).
CAM seems to be particularly useful in treating FM because conventional
therapies, namely drugs, are only partially effective and may have undesirable
side effects. The treatments focus on the overall health of the person with FM,
including his or her emotional state and nutritional health, and how these states
can affect the condition. A review article found the largest improvements occurred
with mind/body techniques, such as biofeedback, hypnosis, and
cognitive
behavioral therapy, especially when they were part of a
multidisciplinary approach to treatment. Acupuncture
was only moderately effective, while manipulative techniques such as chiropractic
and massage were least effective. Another study, however, showed that just twenty
minutes of moderate-pressure massage can lessen the flow of chemicals associated
with pain and stress while increasing production of serotonin, a nerve transmitter
that improves mood.
Osteoporosis
Osteoporosis (OP), or “porous bone,” is the gradual
weakening of bone structure caused by the depletion of calcium and other minerals.
The condition can lead to bone fractures. Fractures are most common in the arm
bone, vertebrae, and hip. Women are more subject to OP than men, but before
menopause, estrogen secretion provides a protective effect against OP. For both
prevention and treatment of OP, emphasis is placed on consuming adequate calcium
and vitamin
D and engaging in weight-bearing exercises. Prevention is
more successful than treatment.
Estrogen therapy was common practice for postmenopausal women because of the
beneficial effects in preventing hot flashes and reducing OP. However, a large
Women’s Health Initiative Study concluded that the health risks of estrogen
therapy exceeded its benefits. In the search for alternatives to estrogen therapy,
attention has focused on the use of dietary isoflavones. Isoflavones are
non-nutritive compounds found in relatively large amounts in soybeans. The most
common isoflavones are genistein and daidzein. They are also known as
phytoestrogens, because they are similar in structure to estrogens and have weak
estrogenic activity. Researchers have shown that isoflavones bind to estrogen
receptors in osteoblast (bone-forming) cells, although in a manner different from
estrogen. As a result, isoflavones were characterized as selective estrogen
receptor modulators that could provide some of the beneficial effects of estrogen
without the negative effects. Isoflavones could also inhibit osteoclast
(bone-breakdown) cells by decreasing acid secretion or regulatory enzyme
activities.
A review article summarized the results of two double-blind, randomized-control studies and one case-control study. Those persons receiving isoflavone treatments showed improvements in bone mass and reductions in the loss of bone mass, compared with those persons in the control group.
Another study evaluated the effect of isoflavones on bone resorption. Subjects were provided with radioactive calcium and three levels of isoflavones in a double-blind, randomized-control study. Serum and urinary samples were taken and analyzed for radioactive calcium to determine the rate of bone resorption (loss). Isoflavones did not have any influence on bone resorption.
Another study compared the effect of isoflavones on bone mineral density (BMD) in men and women. The results showed that isoflavones had a modest benefit in preserving spine but not hip BMD in women.
Bibliography
Beers, Mark H., ed. The Merck Manual of Medical Information, Second Home Edition. Whitehouse Station, N.J.: Merck Research Laboratories, 2003. This is the layperson’s version of professional Merck Manual of Diagnosis and Therapy. Provides an excellent discussion of bone and joint disorders.
Brynin, Rona. “Soy and Its Isoflavones: A Review of Their Effects on Bone Density.” Alternative Medicine Review 7, no. 4 (2002): 317-326. Describes the nature of soy isoflavones and relevant studies to evaluate the effect of isoflavones on bone density.
Clegg, Daniel, et al. “Glucosamine, Chondroitin Sulfate, and the Two in Combination for Painful Knee Osteoarthritis.” New England Journal of Medicine 354 (February 23, 2006): 795-808. Reports on the effect of glucosamine and chondroitin on pain alleviation in GAIT studies.
Kelly, Gregory. “The Role of Glucosamine Sulfate and Chondroitin Sulfates in the Treatment of Degenerative Joint Disease.” Alternative Medicine Review 3, no. 1 (1998): 27-39. Describes the structure and metabolism of glucosamine and chondroitin and discusses relevant clinical trials.
National Center for Complementary and Alternative Medicine. “Rheumatoid Arthritis and CAM.” Available at http://www.nccam.nih.gov/health/ra. Provides a summary of all CAM methods that treat symptoms of rheumatoid arthritis.
Reichenbach, Stephan, et al. “Meta-analysis: Chondroitin for Osteoarthritis of the Knee or Hip.” Annals of Internal Medicine 146 (2007): 580-590. Concludes that chondroitin showed no benefit for osteoarthritis in those studies that were large and well designed.
Sawitzke, Allen, et al. “ The Effect of Glucosamine and/or Chondroitin Sulfate on the Progression of Knee Osteoarthritis.” Arthritis and Rheumatism 58, no. 10 (2008): 3183-3191. Reports on the effect of glucosamine and chondroitin on reducing cartilage loss in osteoarthritis in GAIT studies.
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