Cyrus Behzadi, Presenter: Nothing to Disclose

Azien Laqmani, Abstract Co-Author: Nothing to Disclose

Frank Oliver Gerhard Henes MD, Abstract Co-Author: Nothing to Disclose

Michael Gerhard Kaul, Abstract Co-Author: Nothing to Disclose

Gerhard B. Adam MD, Abstract Co-Author: Nothing to Disclose

Marc Regier, Abstract Co-Author: Nothing to Disclose

To quantitatively assess the immediate effect of a 45 minute endurance run on articular cartilage of the knee using T2 and T2* relaxation measurements at 3T. 

The study collective consisted of 30 young male adults (18–31 years) who routinely perform sports at an amateur level without prior knee injury. After resting for 30 minutes in supine position, all participants underwent an initial MRI at 3T. For quantitative analysis T2 (16 echo times ranging from 9.7-154.6ms; image resolution, 0.5x3x3mm) and T2* (22 echo times ranging from 4.6-52.9ms; image resolution 0.5x2x2mm) measurements were performed in sagittal orientation. All participants then performed a 45 minutes endurance run using a treatmill at medium level (mean, 6.5 mph). After the run, all individuals were re-examined identically with a delay of 2 to 6 minutes. All data sets were postprocessed using a dedicated software (ImageJ) and quantitative maps were generated. 22 regions-of-interest (ROI) were manually drawn in the areas of the femoral, tibial and patellar cartilage. For statistical evaluation a Wilcoxon-matched-pairs analysis was performed.

After the run, a significant decrease in mean T2 and T2* relaxation times was observed for all segments in all participants. The highest decrease was determined for the medial femoral segments, here the T2 values decreased from 36.58ms to 31.13ms (14.91%; p=0.02) and the T2* values decreased from 23.75ms to 19.14ms (19.4%; p<0.001). The effect of running was higher at the anterior segments than posteriorly, here the mean values decreased from 42.45ms to 37.08ms (12.65%; p=0.02) for T2 and from 32.36ms to 26.87ms (16.96%; p=0.01) for T2* measurements. The lateral basis of the patella was least effected by the axial load during running, here a mean decrease of 8.1% (T2; p=0.06) and 11.6% (T2*; p=0.03) was noted.

The presented data underline the ability of T2 and T2* mapping to quantitatively assess the acute effect of endurance running on the articular cartilage of the knee. Based on our results, this effect seems to predominate in the anterior and medial articular facette whereas the posterior segments of the femur are not affected in the same level. 

T2 and T2* show a high concordance in the assessment of acute exercise related changes to the articular cartilage of the knee and can be useful in the detection of initial cartilage degeneration.

Behzadi, C, Laqmani, A, Henes, F, Kaul, M, Adam, G, Regier, M, The Immediate Effect of Athletic Endurance Running on T2 and T2*-relaxation Times of Articular Cartilage of the Knee in Young Healthy Adults at 3T MRI.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14009417.html