A comparison of ultrasound-guided rotator interval and posterior glenohumeral injection techniques for MR shoulder arthrography

Purpose: The aim of this prospective, randomized study was to compare the performance of a rotator interval approach with the posterior glenohumeral approach for ultrasound-guided contrast injection prior to MR shoulder arthrography. Method: This study was approved by the institutional review board. One hundred and twenty consecutive patients referred for MR shoulder arthrography were randomized into four groups: rotator interval approach inplane (n = 30); rotator interval approach out-of-plane (n = 30); posterior approach in-plane (n = 30); and posterior approach out-of plane (n = 30). Outcome measures included procedure time, number of injection attempts, patient-reported pain score (0 -10), and radiologist-reported technical difficulty (0-10). MR arthrograms were assessed for adequacy of joint distension, diagnostic utility, and extra-capsular contrast leakage. Results: All 120 patients had a successful ultrasound-guided injection with adequate joint distension and diagnostic utility for MR arthrography. In-plane needle guidance was less technically demanding, quicker, required fewer injection attempts, and had a lower frequency of contrast leakage than out-of-plane needle guidance. The posterior glenohumeral approach was less technically demanding though had a higher frequency of contrast leakage and caused more patient discomfort than the rotator interval approach. Conclusion: For ultrasound-guided shoulder joint injection, an in-plane approach is preferable. The posterior glenohumeral approach is less technically demanding though causes more patients discomfort than the rotator interval approach possibly due to the longer needle path.