Feature | Orthopedic Imaging | December 01, 2015

MRI Reveals Weight Loss Protects Knees

Patients who lost more than 10 percent of their body weight had slower degeneration of their knee cartilage

RSNA 2015, MRI study, weight loss, knee cartilage degeneration

Figure 1. Cartilage T2 maps indicating worsening cartilage quality (red) after 48 months in an obese patient without weight loss (top row) compared to a patient with >10 percent weight loss (bottom row) in which only little cartilage degeneration is found.

RSNA 2015, MRI study, weight loss, knee cartilage degeneration, knee joint

Figure 2. Knee joint of patient without weight loss (A) showing severe cartilage defects after 48 months, whereas in the knee joint of a patient with a substantial amount of weight loss (B), cartilage remains intact.

November 30, 2015 — Obese people who lose a substantial amount of weight can significantly slow knee cartilage degeneration, according to a new magnetic resonance imaging (MRI) study presented today at the annual meeting of the Radiological Society of North America (RSNA).

Obesity is a major risk factor for osteoarthritis, a degenerative joint disease that affects more than a third of adults over the age of 60, according to the Centers for Disease Control and Prevention. The knee joint is a common site of osteoarthritis, and in many people the condition progresses until total knee replacement becomes necessary. Aging baby boomers and a rise in obesity have contributed to an increased prevalence of knee osteoarthritis.

"Degenerative joint disease is a major cause of pain and disability in our population, and obesity is a significant risk factor," said the study's lead author, Alexandra Gersing, M.D., from the Department of Radiology and Biomedical Imaging at the University of California, San Francisco. "Once cartilage is lost in osteoarthritis, the disease cannot be reversed."

Gersing and colleagues recently investigated the association between different degrees of weight loss and the progression of knee cartilage degeneration in 506 overweight and obese patients from the Osteoarthritis Initiative, a nationwide research study focused on the prevention and treatment of knee osteoarthritis. The patients either had mild to moderate osteoarthritis or risk factors for the disease. They were divided into three groups: a control group who did not lose weight, a second group who lost a little weight, and a third group who lost more than 10 percent of their body weight. The researchers then used MRI to quantify knee osteoarthritis.

"Through T2 relaxation time measurements from MRI, we can see changes in cartilage quality at a very early stage, even before it breaks down," Gersing said.

When the researchers analyzed differences in the quality of cartilage among the three groups over a four-year time span, they found evidence that weight loss has a protective effect against cartilage degeneration and that a larger amount of weight loss is more beneficial.

"Cartilage degenerated a lot slower in the group that lost more than 10 percent of their body weight, especially in the weight-bearing regions of the knee," Gersing said. "However, those with 5 to 10 percent weight loss had almost no difference in cartilage degeneration compared to those who didn't lose weight."

Substantial weight loss not only slows knee joint degeneration—it also reduces the risk of developing osteoarthritis, Gersing said. Along with moderate exercise, weight loss is one of the primary interventions against the disease.

"It's most helpful if these lifestyle interventions take place as early as possible," Gersing said.

In the future, the researchers are planning to study the role of diabetes, which is closely linked with obesity, in cartilage degeneration. They also plan to do an eight-year follow-up with the patient group and look at what effects weight gain may have on the knee joint.

Co-authors on the study are Martin Solka; Gabby B. Joseph, Ph.D.; Benedikt J. Schwaiger, M.D.; Ursula R. Heilmeier, M.D.; Georg Feuerriegel; John Mbapte Wamba, M.D.; Charles E. McCulloch, Ph.D.; Michael C. Nevitt, Ph.D.; and Thomas M. Link, M.D., Ph.D.

For more information: www.radiologyinfo.org

Related Content

MRI Plus Mammography Improves Detection of New Breast Cancer After Surgery
News | Breast Imaging | June 22, 2017
A new article published by JAMA Oncology compares outcomes for combined mammography and magnetic resonance imaging (MRI...
Dual-Agent PET/MR With Time of Flight Detects More Cancer

Tc-99m MDP bone scan (left) is negative for osseous lesions. NaF/FDG PET/MRI (right and second slide) confirms absence of bone metastases, but shows liver metastases. Image courtesy of Stanford University.

News | PET-MRI | June 20, 2017
Simultaneous injections of the radiopharmaceuticals fluorine-18 fluorodeoxyglucose (18F-FDG) and 18F-sodium fluoride (...
Combined Optical and Molecular Imaging Could Guide Breast-Conserving Surgery

WLE specimen from a patient with a grade 3, ER-/HER2-, no special type (NST) carcinoma. (A) Cerenkov image; (B) Grey-scale photographic image overlaid with Cerenkov signal. An increased signal from the tumor is visible (white arrows); mean radiance is 871 ± 131 photons/s/cm2/sr, mean TBR is 3.22. Both surgeons measured the posterior margin (outlined in blue) as 2 mm (small arrow); a cavity shaving would have been performed if the image had been available intraoperatively. The medial margin (outlined in green) measured >5 mm by both surgeons. Pathology ink prevented assessing the lateral margin; a phosphorescent signal is visible (open arrows). (C) Specimen radiography image. The absence of one surgical clip to mark the anterior margin, and the odd position of the superior margin clip (white arrow) prevented reliable margin assessment. (D) Combined histopathology image from two adjacent pathology slides on which the posterior margin (bottom of image) and part of the primary tumor are visible (open arrows). The distance from the posterior margin measured 3 mm microscopically (double arrow). The medial margin is > 5 mm (not present in image). Credit: A. D. Purushotham, M.D., King’s College London, UK

News | Nuclear Imaging | June 20, 2017
June 20, 2017 — Breast-conserving surgery (BCS) is the primary treatment for early-stage...
Henry Ford Cancer Institute First in World to Install Viewray MRIdian Linac
News | Image Guided Radiation Therapy (IGRT) | June 19, 2017
The Henry Ford Cancer Institute is the first in Michigan – and first in the world – to offer patients advanced...
The Magnetom Vida with BioMatrix technology
News | Magnetic Resonance Imaging (MRI) | June 16, 2017
The U.S. Food and Drug Administration (FDA) has cleared the Magnetom Vida 3 Tesla (3T) magnetic resonance imaging (MRI...
Stéphane Bordas, Professor in Computational Mechanics at the Faculty of Science, Technology and Communication of the University of Luxembourg, and his team have developed methods to train surgeons, help them rehearse for such complex operations and guide them during surgery

Stéphane Bordas, Professor in Computational Mechanics at the Faculty of Science, Technology and Communication of the University of Luxembourg, and his team have developed methods to train surgeons, help them rehearse for such complex operations and guide them during surgery. Image © Legato Team / University of Luxembourg.

News | Information Technology | June 16, 2017
Researchers from the University of Luxembourg, in cooperation with the University of Strasbourg, have developed a...
pediatric imaging
News | Pediatric Imaging | June 14, 2017
Despite evidence showing that the routine use of sonography in hospital emergency departments can safely improve care...

Image courtesy of Carestream

News | Business | June 13, 2017
Communication between patients and radiologists is a key element of patient-centered care, a major focus of the...
News | PET-CT | June 12, 2017
Siemens Healthineers has announced that the Food and Drug Administration (FDA) has cleared Biograph Horizon Flow...
News | Clinical Study | June 09, 2017
The milestone Imaging Dementia — Evidence for Amyloid Scanning (IDEAS) Study is working with government and academic...
Overlay Init