Shoes: A treatment for osteoarthritis in the knees?

March 24, 2010

Flip-flops and sneakers with flexible soles are easier on the knees than clogs or even special walking shoes, a study by Rush University Medical Center has found. And that's important, because loading on the knee joints is a key factor in the development of osteoarthritis.

The study has been published online in the journal Care & Research.

"Traditionally, footwear has been engineered to provide maximum support and comfort for the foot, with little attention paid to the biomechanical effects on the rest of the leg," said Dr. Najia Shakoor, a rheumatologist at Rush and the primary author of the study. "But the shoes we wear have a substantial impact on the load on the , particularly when we walk."

"Our study demonstrated that flat, flexible footwear significantly reduces the load on the knee joints compared with supportive, stable shoes with less flexible soles."

is the most common form of arthritis and a significant source of disability and impaired quality of life. A higher-than-normal load on the knees during walking is a hallmark of the disease, associated with both the severity of osteoarthritis and its progression.

Shakoor and her colleagues analyzed the gait of 31 patients with symptoms of osteoarthritis in the Rush Motion Analysis Lab while they walked barefoot and with four popular shoe types: Dansko clogs, which are often worn by healthcare professionals who have to be on their feet much of the day; Brooks Addiction stability shoes, which are prescribed for foot comfort and stability; Puma H-Street shoes, a flat athletic shoe with flexible soles; and flip-flops.

The loads on the knee joints differed significantly depending on the footwear. For the clogs and stability shoes, the loads on the knee joints were up to 15 percent greater than with the flat walking shoes, flip-flops or barefoot walking. Knee loading was roughly the same whether the subject wore flips-flops or walked barefoot.

"Currently, knee braces and wedged orthotic shoe inserts are used to relieve the load on the knee joints of patients with osteoarthritis, but everyday footwear is also a factor to consider. The results in our study demonstrate that the reduction in load achieved with different footwear, from 11 to 15 percent, is certainly comparable to reduction in load with braces and shoe inserts ," Shakoor said.

According to Shakoor, several aspects of footwear affect the joint loading.

"Heel height is one factor, and may explain why the stability shoes and clogs in our study, both of which had higher heels, produced greater knee loads," Shakoor said.

"Stiffness is also a factor. We've shown in earlier studies that barefoot walking is associated with lower knee loads than walking with conventional footwear. It may be that the flexible movement of the bare foot is mechanically advantageous. The natural flex of the foot when it contacts the ground probably attenuates the impact on the joint, compared to the artificial 'stomping' movement created by a stiff-soled shoe."

In the present study, Shakoor said, flip-flops and the walking shoe were flat, flexible and lightweight and seemed to mimic the mechanics when walking with bare feet.

"Clogs and stability shoes, conventionally believed to provide appropriate cushioning and support, actually increased the loading on the knee joints, as opposed to shoes with less 'support,' flatter heels and more flexibility," Shakoor said.

Shakoor cautioned, however, that knee loading is not the only consideration in any clinical recommendations based on her study.

"For the elderly and infirm individuals, flip-flops could contribute to falls because of their loose-fitting design. Factors like these need to be taken into account," Shakoor said.

Related Stories

Recommended for you

Groundbreaking investigative effort identifies gonorrhea vaccine candidates

September 19, 2017
Researchers at Oregon State University have identified a pair of proteins that show promise as the basis for a gonorrhea vaccine.

Snail fever progression linked to nitric oxide production

September 14, 2017
Bilharzia, caused by a parasitic worm found in freshwater called Schistosoma, infects around 200 million people globally and its advance can lead to death, especially in children in developing countries.

Systems analysis points to links between Toxoplasma infection and common brain diseases

September 13, 2017
More than 2 billion people - nearly one out of every three humans on earth, including about 60 million people in the United States - have a lifelong infection with the brain-dwelling parasite Toxoplasma gondii.

Study clears important hurdle toward developing an HIV vaccine

September 13, 2017
An international team of researchers has demonstrated a way of overcoming one of the major stumbling blocks that has prevented the development of a vaccine against HIV: the ability to generate immune cells that stay in circulation ...

As 'flesh-eating' Leishmania come closer, a vaccine against them does, too

September 13, 2017
Parasites that ulcerate the skin, can disfigure the face, and may fatally mutilate its victim's internal organs are creeping closer to the southern edges of the United States.

Promising clinical trial results could give doctors a new tool against drug-resistant strains of malaria parasite

September 13, 2017
Tulane University researchers have developed a new drug that is effective against non-severe cases of malaria, according to results from an FDA-supervised clinical trial published in the latest issue of The Lancet Infectious ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.