Chapter 3 Instability

180

CHAPTER 3 | Instability

FIGURE 3-105  MR arthrogram in a right shoulder. A: Axial image demonstrates an intact anterior labrum without evidence of glenoid bone loss or a Hill-Sachs defect. B: Coronal image demonstrates a HAGL lesion as shown by the “J” sign.

Pearls, Pitfalls, and Decision-making: ■ The classic MRI finding for a HAGL lesion is the “J” sign, which results from inferomedial retraction of the humeral attachment of the glenohumeral ligaments. This finding is most pronounced with intra-articular contrast (MR arthrogram) ■ The HAGL lesion may be viewed from either the ASL portal or the posterior portal; a 70° arthroscope is often helpful to facilitate visualization ■ The first step is determining if an adequate angle of approach (the “killer angle”) can be achieved for suture anchor placement. If this is not possible, a safe

conversion can be made to an open procedure before substantial swelling occurs. ■ Several steps are used to improve visualization: ■ HAGL repair should be performed prior to labral repair to maximize the ability to work in this tight space. ■ A Gemini cannula can be used to retract the ante- rior structures and increase the anterior working space. ■ For a knotless repair, all sutures are passed prior to anchor placement rather than sequentially passing a suture and placing an anchor.

FIGURE 3-106  Right shoulder, anterosuperolateral viewing portal with a 70° arthroscope demonstrates (A) a HAGL lesion, followed by (B) arthroscopic repair. H, humeral head.