The purpose of this study was to investigated the efficiency of the radial plane of MR arthrography(MRA) for superior labral lesions in a painful throwing shoulder. The twelve painful throwing shoulders were examined. Age of the patients were 16-33 years old (mean 21.3 years old ) and patients had either signs and symptoms of superior labral lesions. Each patient underwent a radial MRA after intra-articular injection of 10ml of 0.5% mepivacaine. Superior labral lesions of all patients were categorized according to Yamasaki's classification, and the findings on the MRA were correlated with the arthroscopical findings. MRA was performed with 1.0-T system (SIEMENS HARMONY). All patients were supine with the humerus in the neutral position. After a radial localizing imaging, intensity and morphological changes in the labrum through all the o'clock positions of the glenoid rim in T2 star images by the FRASH method were evaluated. When we diagnose Type II-B, type III or type IV as a superior labral lesion, this study showed 87% of sensitivity,78.9% of specificity, and 81.3% of accuracy through all the o'clock positions of the glenoid rim on the radial plane of MRA. A radial MRA was useful to diagnose the superior labral leision in painful throwing shoulder. Though 0.5% mepivacaine is cheaper than gadopentetate meglumine, it did not influenced the enhancement effect.
