Osteoarthritis (OA) is the most common form of arthritis and affects approximately 30 million Americans. The underlying pathology is altered biochemical changes in cartilage- the gristle that caps the ends of long bones. Cartilage consists of cells called chondrocytes that produce a matrix. The chondrocytes sit inside this matrix, much like grapes inside gelatin.
With the development of OA, the chondrocytes no longer function properly. In addition, inflammatory changes occur within the joint. The end result is progressive and gradual loss of cartilage- leading to altered mechanics. Pain develops as a result of a number of factors including inflammation of the lining of the joint, stimulation of pain receptors in the joint capsule, and stretching of ligaments and tendons due to the altered biomechanics.
While, OA tends to affect weight-bearing joints such as the neck, low back, hips, and knees, the area that seems to be responsible for most visits to a rheumatologist's office is OA of the knee.
Conservative OA of the knee treatment consists of a comprehensive program incorporating patient education, weight loss, exercise, non-steroidal-anti-inflammatory drugs, glucocorticoid (cortisone injections), and viscosupplementation (injections of lubricant material).
In a previous article, I discussed the use of bracing for OA of the knee, which is another conservative measure.
In this article I discuss a little-known but very effective means of reducing knee pain called the lateral wedge insole.
Lateral wedged insoles are aimed at patients with varus deformity knee OA. A varus deformity means the patient has ?bow-legs?. Patients with varus knee deformities due to OA have significant pain involving the medial (inside) part of the knee.
A number of studies have demonstrated that the use of the lateral wedge insole, by lifting the outside of the foot, leads to valgus angulation of the ankle, resulting in slight correction of the varus knee deformity.
Measures that many studies have included are subjective daytime pain, night time pain, length of time required to walk 50 feet, and reduction in need for non steroidal anti-inflammatory drugs.
Different types of wedges are available. Some wedges are simply inserted inside a shoe. Other wedges come with a strap that provides stability of the wedge inside the shoe.
According to one of the authors responsible for the development of a popular wedged insole device, "The prevalence of knee OA in our society is increasing due to the escalating proportion of elderly persons. A conservative therapy such as the use of an insole that provides a low-cost complement or alternative to surgical treatment would be a very useful adjunct to the care of patients with knee OA and would benefit the health economy."
[Toda Y and Tsukimura N. Randomised trial to compare the clinical effects of an insole with subtalar strapping and knee support with hinged struts for patients with varus deformity osteoarthritis of the knee. Arthritis Rheum 2004; 50 (9) (supplement).
Toda Y and Tsukimura N. A six-month follow-up of a randomised trial to compare the efficacy of a lateral wedge insole with subtalar strapping and an in-shoe lateral wedged insole in patients with varus deformity osteoarthritis of the knee. Arthritis Rheum 2004; 50 (9) (supplement)].
While some detractors point to flaws in study design, abundant anecdotal evidence as well as the multiplicity of studies pointing towards effectiveness, suggest that these insoles should at least be given a try.
OA is a disease of articular cartilage, the gristle that caps and cushions the ends of long bones and allows the joint to glide. With OA, the cartilage begins to wear away prematurely.
Weight-bearing areas such as the neck, low back, hips, and knees are the areas most often involved. The knee, since it is so important for normal ambulation, is the joint that appears to give most patients a problem.
The treatment of symptomatic OA of the knee revolves around patient education, maintenance of ideal weight, exercise (stretching, strengthening, non impact aerobic), assistive devices such as canes or walkers if necessary, topical rubs, non-steroidal anti-inflammatory drugs (NSAIDS), injections of glucocorticoid (cortisone) or viscosupplements (lubricants) into the joint, and sometimes surgery.
One frequently neglected mode of treatment is bracing. Braces come in all shapes, sizes, and configurations. Braces are divided into two different groups, soft braces and hard braces.
Soft braces or ?sleeves? are made of stretchable material such as synthetic cloth material or neoprene. Soft braces are designed to be either pulled up to fit around the knee or strapped into place using velcro or another similar method.
Soft braces have the benefits of being easy to use and easy to care for. They function by giving the knee a small amount of support. This support may be more of a function of proprioceptors (nerves that provide feedback as to orientation in space) around the knee than it is of actual knee stabilization since cloth or neoprene are not stiff enough to restrict motion. Patients with arthritis in the hands may also have difficulty pulling a sleeve up.
The other type of knee brace is the hard brace. These rigid braces are made of durable molded plastic. They have foam rubber liners for comfort and are reinforced with steel hinges. Technological advances have made these hard braces relatively light-weight but still much heavier than sleeves.
These braces are designed to stabilize the joint and alter knee mechanics. They work by applying pressure to the outside thigh and outside lower leg (on the opposite side from the narrowed part of the knee joint). The result is a redistribution of weight away from the painful inside compartment of the knee.
A number of different companies manufacture these hard braces. The two best companies in the OA of the knee bracing arena (in my opinion) are Generation II and Donjoy.
The braces are custom-fit and therefore expensive, ranging in price from $400-750. Most insurance companies do pay for these braces.
Since bracing is non-invasive- not requiring surgery- and is non-pharmacologic- not requiring drugs- it is a safe and viable alternative for patients with symptomatic OA of the knee. It also can be used as a complementary treatment- ie., used in conjunction with other forms of treatment.
In our clinic, we have found that some patients may require arthroscopy if they have meniscus tears (damage to cartilage in the knee). After an arthroscopy they often undergo viscosupplementation treatment. A rigid brace, following either or both of these other procedures, is an excellent complementary treatment.
Some studies have suggested that bracing can postpone the need for knee replacement.
Nathan Wei has sinced written about articles on various topics from Arthritis Pain, Health and Arthritis Signs. Nathan Wei, MD FACP FACR is a rheumatologist and Director of the Arthritis and Osteoporosis Center of Maryland. He is a Clinical Assistant Professor of Medicine at the University of Maryland School of Medicine. For more info:. Nathan Wei's top article generates over 550000 views. to your Favourites.