Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Too much or too little activity bad for knees

26.11.2012
Both very high and very low levels of physical activity can accelerate the degeneration of knee cartilage in middle-aged adults, according to a new study presented at the annual meeting of the Radiological Society of North America (RSNA).

Nearly one in every two people in the U.S. may develop knee osteoarthritis by age 85, according to the Centers for Disease Control and Prevention. By 2030, an estimated 67 million Americans over the age of 18 are projected to have physician-diagnosed arthritis.

Researchers at the University of California in San Francisco (UCSF) previously had found an association between physical activity and cartilage degeneration. But that study focused on one point in time.

For the new study, the UCSF researchers looked at changes in knee cartilage among a group of middle-aged adults over a four-year period. They used magnetic resonance imaging (MRI)-based T2 relaxation times to track the evolution of early degenerative cartilage changes in the knee.

"T2 relaxation times generated from MR images allow for analysis of the biochemical and molecular composition of cartilage," said Wilson Lin, B.S., research fellow and medical student at UCSF. "There is increased water mobility in damaged cartilage, and increased water mobility results in increased T2 relaxation time."

The researchers analyzed 205 patients, age 45 to 60, from the UCSF-based Osteoarthritis Initiative, a nationwide study funded by the National Institutes of Health on the prevention and treatment of knee osteoarthritis. Participants used a questionnaire to record their physical activity. The researchers measured T2 values of cartilage at the patella, femur and tibia of the right knee joint at baseline and at two- and four-year visits.

According to the results of the study, participating frequently in high-impact activities, such as running, appears associated with more degenerated cartilage and potentially a higher risk for development of osteoarthritis.

"When we compared the scores among groups, we found an accelerated progression of T2 relaxation times in those who were the most physically active," said Thomas M. Link, M.D., professor of radiology and chief of musculoskeletal imaging at UCSF. "Those who had very low levels of activity also had accelerated progression of T2 values. This suggests that there may be an optimal level of physical activity to preserve the cartilage."

The results open up numerous areas for future inquiry, including analysis of the impact of specific types of physical activity on knee cartilage health. For instance, some of the participants in the Osteoarthritis Initiative wore an accelerometer, a device with a motion sensor to record physical activity.

"In this study, we used the subjective measure of a questionnaire," Lin said. "The accelerometers provide a more objective way to measure physical activity."

Along with the findings on changes in knee cartilage, the study also highlighted the potential of T2 relaxation times as an early indicator of cartilage degeneration.

"Standard MRI shows cartilage defects that are irreversible," Dr. Link said. "The exciting thing about the new cartilage T2 measurements is that they give us information on a biochemical level, thus potentially detecting changes at an earlier stage when they may still be reversible."

Dr. Link noted that people who have a higher risk for osteoarthritis (such as family history of total joint replacement, obesity, history of knee injury or surgery) can reduce their risk for cartilage degeneration by maintaining a healthy weight and avoiding risky activities and strenuous, high-impact exercise.

"Lower impact sports, such as walking or swimming, are likely more beneficial than higher impact sports, such as running or tennis, in individuals at risk for osteoarthritis," he said.

Coauthors are Waraporn Srikhum, M.D., Charles E. McCulloch, Ph.D., Michael Neitt, Ph.D., John Lynch, Ph.D., Gabby B. Joseph, Ph.D., and Hamza Alizai, M.D.

Note: Copies of RSNA 2012 news releases and electronic images will be available online at RSNA.org/press12 beginning Monday, Nov. 26.

RSNA is an association of more than 50,000 radiologists, radiation oncologists, medical physicists and related scientists, promoting excellence in patient care and health care delivery through education, research and technologic innovation. The Society is based in Oak Brook, Ill.

Editor's note: The data in these releases may differ from those in the published abstract and those actually presented at the meeting, as researchers continue to update their data right up until the meeting. To ensure you are using the most up-to-date information, please call the RSNA Newsroom at 1-312-949-3233.

For patient-friendly information on MRI of the knee, visit RadiologyInfo.org.

Linda Brooks | EurekAlert!
Further information:
http://www.rsna.org
http://RadiologyInfo.org

More articles from Studies and Analyses:

nachricht The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung

nachricht A sudden drop in outdoor temperature increases the risk of respiratory infections
11.01.2017 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>