Ultrasound-guided shoulder MR arthrography: comparison of rotator interval and posterior approach

The purpose of this study was to prospectively evaluate the two different ultrasound-guided injection techniques for magnetic resonance (MR) arthrography of the shoulder.

This study included 100 patients [50 rotator interval group (n=50) vs. 50 posterior approach group (n=50)]. All procedures were performed by the same radiologist. The two injection techniques were compared. The discomfort during and after arthrography was evaluated. Extraarticular contrast media extravasation was graded according to the MRI findings. The number of injection attempts, effect of contrast media extravasation rate on diagnostic quality and procedure times were recorded.

There were no significant difference between the posterior and rotator interval puncture groups with regard to pain (P=.915), procedure times (P=.401) or attempt scores (P=.182). There were significantly more contrast media extravasations with rotator interval approach than posterior approach (P<.05).

Both techniques were successful and well tolerated by patients. Posterior injection technique provided a more effective route with decreased extravasation rate and easier approach compared to the rotator interval approach.