• Injuries to the inferior glenohumeral ligament (IGHL) and capsulolabral complex may occur at the glenoid origin (40%) or present as an intrasubstance tear (35%) or tear at the humeral insertion (25%).

• The incidence of humeral avulsion of the glenohumeral ligament (HAGL) is 1%-9% in patients presenting with glenohumeral instability (Fig. 9-1).

• Special attention should be paid to intrasubstance tears of the IGHL and capsule, which appear parallel to its fibers. This may present similarly to an HAGL but without frank capsular detachment at the humeral insertion and can be repaired with side-to-side sutures passed and tied arthroscopically. In these cases, imaging is consistent with escape of fluid from the capsule and a positive “J sign” on MRI, but an intact humeral attachment is seen arthroscopically.¹,²

• Biomechanical studies show that large anterior HAGL lesions increase glenohumeral rotation and translation. Repair of these large HAGL lesions restores range of motion (ROM) and translational stability similar to native condition.³,⁴

• Positioning

• Beach chair, with patient elevated 45 degrees

• Arm holder as preferred

• Approach

• The arm is positioned so that it is forward-flexed in line with the body and in neutral rotation to assist with the surgical approach.

• An incision is made over the deltopectoral interval, slightly more vertically than otherwise would be used for shoulder arthroplasty or proximal humeral work. The incision should extend from superior border of the coracoid to just above the axillary fold, ˜7 cm.

• Dissection with cautery is carried through fat until deep muscular fascia is reached. The cephalic vein (typically found proximally and medially in the wound) is identified, the plane medial to the vein is dissected, and the vein is retracted laterally. Crossing veins are ligated with cautery.

• The deep deltopectoral interval is developed and retracted with a self-retaining retractor (Kolbel retractor, George Tiemann & Co., Hauppauge, NY).

• The clavipectoral fascia is incised with Metzenbaum scissors lateral to the muscular component of the conjoint tendon.

• The Kolbel retractor is adjusted to retract the proximal conjoint tendon medially, with care not to place excessive tension on the musculocutaneous nerve.

• The arm is externally rotated to place tension on the subscapularis tendon.

• Landmarks include the long head of the biceps tendon and the bicipital groove laterally and the upper border of the subscapularis tendon and rotator interval proximally.

• Tenotomy and release

• An L-shaped subscapularis tenotomy is made with a vertical limb 1 cm medial to the insertion on the lesser tuberosity at the superolateral corner of the subscapularis and the transverse limb inferiorly (Fig. 9-2). This maintains a 1-cm cuff of subscapularis tendon insertion laterally for repair. We begin this tenotomy inferiorly.

• The upper two-thirds of the subscapularis typically appear more tendinous, while the lower onethird typically appears more muscular. At this junction, a transverse plane is developed parallel to the fibers of the subscapularis with two small Freer elevators.

• The plane between the upper two-thirds of the subscapularis (superficial) and the anterior capsule (deep) is developed with a small periosteal elevator, which is left in place to place tension on the subscapularis tendon.

• With the subscapularis insertion still attached but retracted, the inferior capsule is examined to confirm that the capsule is completely avulsed from the humerus, because sometimes only a portion of the capsule is avulsed. In cases of incomplete capsular detachment, we detach only a portion of the subscapularis, instead of its entirety.

• Further release of the subscapularis tendon progresses from inferior to superior, medial to its insertion. We find needlepoint cautery helpful to start with a partial-thickness release of the subscapularis tendon to prevent injury to the anterior capsule, deep to the tendon.

• Tagging sutures are placed (we prefer a Mason-Allen type stitch) from inferior to superior as the release progresses.

• Once the tendon is fully released, the plane between the subscapularis and the anterior glenoid medially is bluntly developed, and the subscapularis is retracted medially.

• Alternatively, the upper half of the subscapularis can be preserved.

• An L-shaped tenotomy is made with the transverse limb at the inferior border of the subscapularis, splitting muscle fibers, and the vertical limb is 1.5 cm medial to lesser tuberosity traversing the inferior half of tendon, leaving the superior half of subscapularis tendon undisturbed.⁹

• The axillary nerve is palpated inferiorly.

• The subscapularis is tagged and retracted medially and superiorly.

• As the interval between the capsule and subscapularis is dissected, the HAGL lesion will become visible at the anteroinferior aspect of the glenohumeral neck.

• The remaining anterior capsule is released off the humeral neck and mobilized for repair.

• This is done as an inverse L-shaped capsulotomy, with the transverse limb along the rotator interval and the vertical limb on the border of the anatomic neck/articular margin of the humerus.

• The release of the anterior capsule is continued from superior to inferior.

• At the anteroinferior quadrant of the glenohumeral joint (5-6 o’clock on a right shoulder), the avulsion of the capsule from the humeral neck will be visible extending posteroinferiorly (Fig. 9-3).