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

Medical researchers at Flinders University have established a new link between high body mass index (BMI) and breast cancer survival rates — with clinical data revealing worse outcomes for early breast cancer (EBC) patients and improved survival rates in advanced breast cancer (ABC).

Getty Images

News | Women's Health | May 13, 2021
May 13, 2021 — Medical researchers at Flinders University
National Imaging Solutions, a recognized leader in medical imaging and radiology solutions, announced it has acquired DynaRad — the oldest manufacturer of portable X-ray systems in the US. This new investment will allow National Imaging Solutions to support its customers by supplying them with DynaRad portable X-ray machines, including a mobile field X-ray device using nanotube technology.
News | Radiology Business | May 11, 2021
May 11, 2021 — ...
New Module Creates a Warped MRI Scan that Matches Real-Time Ultrasound Results (Graphic: Business Wire)

New Module Creates a Warped MRI Scan that Matches Real-Time Ultrasound Results (Graphic: Business Wire)

News | Artificial Intelligence | May 07, 2021
3D aMRI not only provides a stunning look inside the "beating brain", but it can also measure this physiological motion in all directions. Here, the amplitude of brain motion is overlayed for each brain slice and orientation in 3D. Image credit: 3D aMRI method outlined in Abderezaei et al. Brain Multiphysics (2021); Terem et al. Magnetic Resonance in Medicine (2021).

3D aMRI not only provides a stunning look inside the "beating brain", but it can also measure this physiological motion in all directions. Here, the amplitude of brain motion is overlayed for each brain slice and orientation in 3D. Image credit: 3D aMRI method outlined in Abderezaei et al. Brain Multiphysics (2021); Terem et al. Magnetic Resonance in Medicine (2021).

News | Magnetic Resonance Imaging (MRI) | May 06, 2021
May 6, 2021 — Magnetic Resonance Imaging
After radiosurgery concurrent with nivolumab in 59-year-old patient with melanoma BM (patient 1; Supplemental Tables 3 and 5), F-18 FET PET at follow-up 12 weeks after treatment initiation (bottom row) shows significant decrease of metabolic activity (TBRmean, ?28%) compared with baseline (top row), although MRI changes were consistent with progression according to iRANO criteria. Reduction of metabolic activity was associated with stable clinical course over 10 mo. CE = contrast-enhanced. Image created by

After radiosurgery concurrent with nivolumab in 59-year-old patient with melanoma BM (patient 1; Supplemental Tables 3 and 5), F-18 FET PET at follow-up 12 weeks after treatment initiation (bottom row) shows significant decrease of metabolic activity (TBRmean, ?28%) compared with baseline (top row), although MRI changes were consistent with progression according to iRANO criteria. Reduction of metabolic activity was associated with stable clinical course over 10 mo. CE = contrast-enhanced. Image created by N. Galldiks et al., Research Center Juelich, Juelich, Germany.

News | PET Imaging | May 05, 2021
May 5, 2021 — For patients with brain metastases, amino acid ...
SmartXR uses a unique combination of hardware and AI-powered software to lighten radiographers’ workloads and provide image acquisition support.

SmartXR uses a unique combination of hardware and AI-powered software to lighten radiographers’ workloads and provide image acquisition support. 

Feature | Digital Radiography (DR) | May 04, 2021 | By Melinda Taschetta-Millane
The COVID-19 pandemic brought about an uptick in
News | Artificial Intelligence | April 30, 2021
April 30, 2021 — Canon Medical is bringing the power of accessible...