Trans-coracoacromial Ligament Glenohumeral Injection With Arthroscopic Confirmation

To arthroscopically evaluate the trans-coracoacromial ligament glenohumeral (GH) injection technique by understanding intra-articular needle-tip placement and potential misplacement and complications.

The technique relies on the palpation of 3 bony landmarks: anterolateral corner of the acromion, superolateral border of the coracoid tip, and curved depression of the distal clavicle. The skin entry site lies on the line connecting the curved depression of the distal clavicle and superolateral border of the coracoid tip, two-thirds of the way from the former and one-third of the way from the latter. The direction of the needle is perpendicular to the triangle formed by the 3 bony landmarks. The technique is used to insufflate the GH joint at the start of shoulder arthroscopy procedures with patients in the beach-chair position. Saline solution is injected, and the position of the needle tip in the GH joint is evaluated arthroscopically. An injection is considered successful if saline solution can be injected and the needle tip can be visualized intra-articularly.

This study enrolled 195 patients undergoing shoulder arthroscopy. Successful needle placement in the GH joint occurred in 179 patients (91.8%); placement occurred through the rotator interval in 122 of these, adjacent or through the long head of the biceps tendon in 41, through the upper subscapularis or anterior supraspinatus in 13, and through the anterior labrum in 3. Regarding the 16 failures (8.2%), the needle position did not allow saline solution to be injected because of high resistance in 3 patients whereas the needle tip was not visualized in 13. The needle tip was presumed to rest within the subscapularis muscle or tendon or the labrum in 10 failed injections.

The trans-coracoacromial ligament injection technique showed a high success rate (91.8%) in anesthetized patients about to undergo arthroscopy, whereas the failed injections mainly occurred because the needle was inserted into the subscapularis or labrum. This technique can be used for awake patients with different diagnoses in multiple settings.

Level IV, diagnostic study.