Do Lateral Wedge Insoles Relieve Pain Due To Osteoarthritis Of The Knee?

Osteoarthritis (OA) is the most common form ofdeformity. Measures that many studies have included
arthritis and affects approximately 30 millionare subjective daytime pain, night time pain, length of
Americans. The underlying pathology is alteredtime required to walk 50 feet, and reduction in need
biochemical changes in cartilage- the gristle that capsfor non steroidal anti-inflammatory drugs. Different
the ends of long bones. Cartilage consists of cellstypes of wedges are available. Some wedges are
called chondrocytes that produce a matrix. Thesimply inserted inside a shoe. Other wedges come
chondrocytes sit inside this matrix, much like grapeswith a strap that provides stability of the wedge
inside gelatin. With the development of OA, theinside the shoe. According to one of the authors
chondrocytes no longer function properly. In addition,responsible for the development of a popular
inflammatory changes occur within the joint. The endwedged insole device, "The prevalence of knee OA
result is progressive and gradual loss of cartilage-in our society is increasing due to the escalating
leading to altered mechanics. Pain develops as a resultproportion of elderly persons. A conservative therapy
of a number of factors including inflammation of thesuch as the use of an insole that provides a low-cost
lining of the joint, stimulation of pain receptors in thecomplement or alternative to surgical treatment
joint capsule, and stretching of ligaments and tendonswould be a very useful adjunct to the care of
due to the altered biomechanics. While, OA tends topatients with knee OA and would benefit the health
affect weight-bearing joints such as the neck, loweconomy." [Toda Y and Tsukimura N. Randomised
back, hips, and knees, the area that seems to betrial to compare the clinical effects of an insole with
responsible for most visits to a rheumatologist'ssubtalar strapping and knee support with hinged
office is OA of the knee. Conservative OA of thestruts for patients with varus deformity osteoarthritis
knee treatment consists of a comprehensiveof the knee. Arthritis Rheum 2004; 50 (9)
program incorporating patient education, weight loss,(supplement). Toda Y and Tsukimura N. A six-month
exercise, non-steroidal-anti-inflammatory drugs,follow-up of a randomised trial to compare the
glucocorticoid (cortisone injections), andefficacy of a lateral wedge insole with subtalar
viscosupplementation (injections of lubricant material).strapping and an in-shoe lateral wedged insole in
In a previous article, I discussed the use of bracingpatients with varus deformity osteoarthritis of the
for OA of the knee, which is another conservativeknee. Arthritis Rheum 2004; 50 (9) (supplement)].
measure. In this article I discuss a little-known butWhile some detractors point to flaws in study design,
very effective means of reducing knee pain calledabundant anecdotal evidence as well as the
the lateral wedge insole. Lateral wedged insoles aremultiplicity of studies pointing towards effectiveness,
aimed at patients with varus deformity knee OA. Asuggest that these insoles should at least be given a
varus deformity means the patient has "bow-legs".try.
Patients with varus knee deformities due to OA haveNathan Wei, MD FACP FACR is a rheumatologist and
significant pain involving the medial (inside) part of theDirector of the Arthritis and Osteoporosis Center of
knee. A number of studies have demonstrated thatMaryland. He is a Clinical Assistant Professor of
the use of the lateral wedge insole, by lifting theMedicine at the University of Maryland School of
outside of the foot, leads to valgus angulation of theMedicine.
ankle, resulting in slight correction of the varus knee