抄録
It was important to evaluate the preoperative state of a torn rotator cuff to perform a successful arthroscopic rotator cuff repair. The purpose of this study was to determine the usefulness of CT arthrography (CTA) for diagnosing rotator cuff tears (RCT). 87 shoulders from 87 patients who had undergone both magnetic resonance imaging (MRI) and CTA preoperatively and subsequent arthroscopy were included in this study. There were 52 men and 35 women. The average age of the patients was 63.4 years old, with a range of 17 to 82 years old. Images of CTA were reconstructed in the oblique-sagittal and oblique-coronal planes same as MRI. The presence and size of RCT were evaluated separately and these results were compared with arthroscopic findings. In CTAs, there were 55 shoulders diagnosed as RCT. There were 16 small tears (less than 1 cm), 17 medium-sized tears (1 to 3 cm), 16 large tears (3 to 5 cm), and six massive tears (more than 5 cm). The presence and size of RCT in CTAs was approximately matched to our arthroscopic findings. MRIs could not detect a complete tear in 15 of 18 small tears diagnosed in CTA. In RCT with a size of larger than 1 cm, findings of MRI and CTA were similar. CTA had a sensitivity of 100%, a specificity of 90.6% and an accuracy of 96.6% for the diagnosis of tears of the supraspinatus. The sensitivity, specificity, and accuracy of MRI was 75.8%, 96.6%, 82.8%, respectively. CTA is useful in evaluating RCT and more sensitive than MRI for detecting a small tear.
