Imaging evaluation of physical activity effect on knee articular cartilage

Introduction

Hyaline cartilage is a complex tissue with great load absorbing-function. Studies showed that moderate exercise can have a positive effect on chondral matrix composition but excessive can be harmful to cartilage.

Objectives

Evaluate knee cartilage thickness before and after physical activity (running) in healthy young individuals.

Methods

Ten healthy young adult male volunteers aged between 18 and 21 years old were selected to undergo magnetic resonance imaging examination of the right knee to measure the cartilage thickness of the anterior, medial, and lateral compartments before and after 1 hour of continuous running. Cartilage thickness measurements were performed by a radiologist who did not know the identity of the volunteers or the moment of the evaluation (before or after the exercise).

Results

The subjects' mean age, height, and weight were 19.5 years, 1.80 m, and 75.2 kg, respectively, with a mean body mass index of 23.14. There was a decrease in chondral thickness after running on all surfaces evaluated. The changes that were relevant (P < .05) were all the medial femoral condyle, the anterior portion of the lateral femoral condyle, the anterior portion of the lateral plateau, the entire surface of the patella and trochlea. The greatest difference in thickness between before and after exercise was observed in the lateral facet of the patella (−0.224 mm) followed by the anterior surface of the medial femoral condyle (−0.186 mm). In proportional values, the highest decrease occurred in the anterior portion of the medial femoral condyle (−11.42%).

Conclusion

There was a decrease in knee chondral thickness after 60 minutes of running, being statistically significant in the medial femoral condyle, anterior surface of the lateral femoral condyle, and lateral plateau and patellofemoral joint (patella and trochlea).

Level of evidence

IV (Case Series).