Featured Research

from universities, journals, and other organizations

Racial disparity observed in varus and valgus thrust study of knee osteoarthritis

Date:
April 29, 2010
Source:
Wiley-Blackwell
Summary:
A recent study determined that African-Americans were less likely to have a varus thrust, but more likely to have valgus thrust than Caucasians. Varus thrust is visualized during gait as the worsening or abrupt onset of varus (bow-legged) alignment as the leg accepts weight, with a return to less varus and more neutral alignment during lift-off of the foot and the swing phase of gait. Prior research has shown that varus thrust seen in gait is associated with a 4-fold increase in the risk of progression of knee osteoarthritis. Disparity in thrust presence between the races may help explain differences in the pattern of osteoarthritic involvement at the knee.

A recent study determined that African-Americans were less likely to have a varus thrust, but more likely to have valgus thrust than Caucasians. Varus thrust is visualized during gait as the worsening or abrupt onset of varus (bow-legged) alignment as the leg accepts weight, with a return to less varus and more neutral alignment during lift-off of the foot and the swing phase of gait. Prior research has shown that varus thrust seen in gait is associated with a 4-fold increase in the risk of progression of knee osteoarthritis (OA). Disparity in thrust presence between the races may help explain differences in the pattern of osteoarthritic involvement at the knee.

Study findings are published in the May issue of Arthritis & Rheumatism, a journal of the American College of Rheumatology.

OA is the most common type of arthritis, characterized by cartilage damage and loss, and causing pain, inflammation, and loss of joint motion. According to The National Institute of Arthritis and Musculoskeletal and Skin Diseases, roughly 27 million Americans 25 years and older have OA. With the aging population, experts project that by 2030 20% of Americans (72 million) will be at risk for developing this disabling disease.

In the current study, a team of researchers from the Feinberg School of Medicine at Northwestern University assessed frequency of varus and valgus thrust in African-Americans and Caucasians and identified factors associated with thrust presence in members of the Osteoarthritis Initiative (OAI) cohort. The OAI thrust study included 3,592 persons (594 African-Americans and 2,998 Caucasians) who were split into two groups: participants without knee OA (n=1,566) and those with OA in one or both knees (n=2026). Those participants without knee OA had a mean age 61 years, a mean body mass index (BMI) of 27.6 kg/m2, and 58.7% were women. In persons with knee OA, the mean age was 63.4 years, the mean BMI was 28.4 kg/m2, and 57.5% were women.

The study revealed that 32.1% of subjects without OA and 36.7% of those with OA had a varus thrust. Valgus thrust was less frequent: 7.2% without OA and 9.1% with OA. The odds of varus thrust were significantly less for African-Americans compared to Caucasians in both disease subgroups, after controlling for other factors. Other factors associated with varus thrust presence in persons without knee OA were age, BMI, varus malalignment, gender (reduced odds in women), and knee extensor strength (reduced odds with greater strength), and, in persons with knee OA, more severe OA disease, varus malalignment, and gender (reduced odds in women).

The odds of valgus thrust were significantly greater for African-Americans compared with Caucasians, in persons without and with knee OA. Also associated with valgus thrust presence in persons without knee OA were valgus malalignment and, in persons with knee OA, more severe lateral disease and valgus malalignment.

"To our knowledge, this is the first report on the frequency of varus and valgus thrust in African-Americans and Caucasians either in persons with or at higher risk of developing knee OA," Dr. Sharma commented. "Further investigation of methods to quantify the elements of a thrust, such as its force and loading rate, will enhance understanding of the mechanism of a thrust effect," concluded the authors. The researchers also caution that persons without knee OA in the OAI thrust study were at high risk of developing it, and thus frequency estimates should not be applied to the general population.


Story Source:

The above story is based on materials provided by Wiley-Blackwell. Note: Materials may be edited for content and length.


Journal Reference:

  1. Alison Chang, Marc Hochberg, Jing Song, Dorothy Dunlop, Joan S. Chmiel, Michael Nevitt, Karen Hayes, Charles Eaton, Joan Bathon, Rebecca Jackson, Kent Kwoh, Leena Sharma. Frequency of varus and valgus thrust and factors associated with thrust presence in persons with or at higher risk for knee osteoarthritis. Arthritis & Rheumatism, 2010; DOI: 10.1002/art.27377

Cite This Page:

Wiley-Blackwell. "Racial disparity observed in varus and valgus thrust study of knee osteoarthritis." ScienceDaily. ScienceDaily, 29 April 2010. <www.sciencedaily.com/releases/2010/04/100429082401.htm>.
Wiley-Blackwell. (2010, April 29). Racial disparity observed in varus and valgus thrust study of knee osteoarthritis. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2010/04/100429082401.htm
Wiley-Blackwell. "Racial disparity observed in varus and valgus thrust study of knee osteoarthritis." ScienceDaily. www.sciencedaily.com/releases/2010/04/100429082401.htm (accessed October 2, 2014).

Share This



More Health & Medicine News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pregnancy Spacing Could Have Big Impact On Autism Risks

Pregnancy Spacing Could Have Big Impact On Autism Risks

Newsy (Oct. 1, 2014) A new study says children born less than one year and more than five years after a sibling can have an increased risk for autism. Video provided by Newsy
Powered by NewsLook.com
Robotic Hair Restoration

Robotic Hair Restoration

Ivanhoe (Oct. 1, 2014) A new robotic procedure is changing the way we transplant hair. The ARTAS robot leaves no linear scarring and provides more natural results. Video provided by Ivanhoe
Powered by NewsLook.com
Insertable Cardiac Monitor

Insertable Cardiac Monitor

Ivanhoe (Oct. 1, 2014) A heart monitor the size of a paperclip that can save your life. The “Reveal Linq” allows a doctor to monitor patients with A-Fib on a continuous basis for up to 3 years! Video provided by Ivanhoe
Powered by NewsLook.com
Attacking Superbugs

Attacking Superbugs

Ivanhoe (Oct. 1, 2014) Two weapons hospitals can use to attack superbugs. Scientists in Ireland created a new gel resistant to superbugs, and a robot that can disinfect a room in minutes. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins