Research Sheds New Light on Running Patterns and Osteoarthritis

The relationship between physical activity and osteoarthritis onset is unclear and complex, which is one reason Peter C. Thurlow, MD, a radiology fellow at the University of Wisconsin (UW), wanted to investigate the association between foot strike patterns in runners and the presence of early degeneration through both biomechanics and MRI. Osteoarthritis is the most common chronic condition of the joints that affects more than 30 million adults in the U.S. alone.

And as an avid runner, Dr. Thurlow was interested in bringing together his personal and professional passions as part of his research project, “Evaluating the Effect of Foot Strike Patterns on MRI of the Knee.”

Recruiting from running clubs and local gyms, the study brought together 16 forefoot strike runners, 24 rearfoot strike runners and 20 asymptomatic non-runners between 25 and 40 years of age with no knee pain or stiffness, no history of prior knee trauma or surgery and no inflammatory or infectious joint disorders.

Each runner first underwent a 3T MR examination of the knee using a 3-D fast spin-echo sequence to detect morphologic joint abnormalities and measure cartilage thickness and a T2 mapping sequence to evaluate cartilage composition and microstructure. Each runner also underwent biomechanical gait analysis at the Biomechanical Gait Analysis Laboratory at the UW Research Park Clinic.

“The timeframe of how cartilage responds to force is still not well understood. This was a very challenging project,” Dr. Thurlow said.

Findings Surprise Researchers

The study confirmed previous research demonstrating the biomechanical benefits of forefoot strike running, such as lower ground force and lower loading rates, on the knee.

“However, our MRI results showed no benefits of fore-foot running,” Dr. Thurlow said. “There was no significant difference in morphologic knee joint abnormalities on MRI including cartilage lesions, meniscus tears, and bone marrow edema lesions, and no significant difference in cartilage thickness measurements between forefoot runners and rearfoot runners.”

In fact, forefoot runners had significantly higher cartilage T2 relaxation time on the medial tibial plateau compared to rearfoot runners, suggesting a greater degree of early cartilage degeneration.

Researchers are still analyzing their data to understand the reason behind that finding.

“You would expect that if you put less force on your lower extremity, it would reduce acute and chronic injury from joint generation,” said Richard Kijowski, MD, a professor of musculoskeletal imaging at the UW School of Medicine and Public Health, who supervised Dr. Thurlow’s project. “That was not the case though.”