2000 Volume 24 Issue 3 Pages 401-404
To detect changes in the shoulder after throwing with Dynamic MRI.
Subjects and methods; We studied 10 shoulder joints of 10 baseball players aged 20 to 22 who belonged to a university baseball club using a 0.3-tesla MR unit before and after throwing. Each player threw a baseball 200 times as hard as he could. Following a first, Gd-DTPA was adminstered intravenously. Gradient echo images were then obtained every 30 seconds, for a total period of 11 minutes. The signal intensity changes for the first 11 minutes were used to calculate the coefficient of enhancement(CE) in regions of interest which were the humeral head, the acromion, the deltoid, the trapezius, the subscapularis, the supraspinatus, the infraspinatus and the teres minor.
Results and discussion. CE after throwing increased in the deltoid, the trapezius, the supraspinatus, the infraspinatus and the teres minor. In cases with joint laxity, CE in the infraspinatus, the teres minor were especially increased. These changes were caused by repetitive throwing. Our findings show that it is possible to objectively evaluate the stress on the shoulder joint caused by throwing using MR imaging.
