Chapter 3 Instability

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CHAPTER 3 | Instability

FIGURE 3-73  A: Left shoulder, anterosuperolateral viewing portal demonstrates a capsular split variant of a reverse humeral avulsion of the glenohumeral ligaments ( black arrow ). B: Up-close view demonstrates muscle visible ( white arrow ) underlying the capsular split. G, glenoid; H, humeral head.

HAGL lesions that extend inferiorly to or beyond the 5 o’clock position can be very difficult to repair arthroscopically due to the extreme obliquity of the angle of approach that is required for suture anchor placement

(the “killer angle”) (Fig. 3-74). Furthermore, we have seen HAGL lesions that extend posterior to the 6 o’clock position, necessitating both anterior and posterior por- tals for repair.

FIGURE 3-74  The killer angle. A: External view in a left shoulder demonstrates the location of the medial low anterior portal ( black arrow ). Note: This portal begins medial to the 5 o’clock portal, which is normally directly inferior to the anterior portal. B: Anterosuperolateral viewing portal demonstrates spinal needle ( white arrow ) location in the glenohumeral joint. C: Up-close view shows the killer angle. The white line parallels the trajectory of the spinal needle. The blue line parallels the humeral head. The angle between these two lines is acute with little room for error. Thus, the phrase “killer angle.” A, anterior portal; ASL, anterosuperolateral portal; H, humeral head; HAGL, humeral avulsion of the glenohumeral ligaments.