33.1 Goals of Procedure

The goals of the procedure are to identify the injury to the posterior capsule of the shoulder and repair the capsule to the site of the avulsion from the humerus without compromising the posterior rotator cuff muscle and tendon.

33.2 Advantages

Open, mini-open, and arthroscopic repair techniques of HAGL/RHAGL lesions have all obtained successful outcomes. ^{1 – 5} All have proven to be successful with few failures in a recent review ³ ; however, arthroscopic treatment provides easier identification of the lesion, minimal damage to the surrounding soft tissues, maximum visualization, less postoperative pain, and improved rehabilitation. Unless other pathology in the shoulder dictates an open approach, we recommend an all-arthroscopic technique for these repairs.

33.3 Indications

All indications and contraindications are considered relative and are dictated by the patient’s pathology and level of disability. As with all instability complaints, the patient’s level of dysfunction dictates the need for operative intervention. Pain and disability are the most important factors to consider when they interfere with normal or desired activity. The majority of patients will present with a traumatic dislocation event, often occurring during a sporting activity. If at all possible, it is important to determine the position of the arm at the time of injury. The most common position of the arm in the setting of RHAGL lesions is abducted and internally rotated at the time of injury. Other signs and symptoms include recurrent dislocations, general sense of “looseness” of the shoulder, shoulder pain, and intermittent popping/catching. ^{6 , 7}

Current thinking may suggest initial nonoperative treatment for traumatic posterior instability focusing on scapular stabilization and rotator cuff strengthening; however, nonoperative management was once the mainstay for treatment after anterior dislocation, and investigations have since shown a lower recurrence of anterior instability after early arthroscopic stabilization in young athletes. ^{8 – 10} Because of this, we advise that young, active patients, especially athletes, undergo surgical correction.

33.4 Contraindications

Contraindications are the presence of an active infection or lack of surgical skill for the appropriate technique.

33.5 Preoperative Preparation/Positioning

A thorough physical examination should be performed on each patient, including comparison to the contralateral shoulder. Great care should be taken to assess for differences in active and passive range of motion as well as strength between the two sides. Extra focus should be placed on the evaluation of the infraspinatus muscle in the presence of RHAGL lesions. While none are specific for HAGL/RHAGL lesions, tests for instability should be performed, including apprehension, posterior jerk, sulcus, and a load and shift. In patients without concomitant labral pathology, one will not feel the usual “grind” during subluxation, as it feels more like an elastic-type shift without the crepitation as the lateral attachment separates from the humerus. Performing a thorough physical examination will also help eliminate or confirm other pathology, which is important as RHAGL lesions have a high incidence of concomitant injuries. ^{7 , 11 , 12}

Standard radiographs are rarely useful to specifically diagnose HAGL/RHAGL lesions except in the setting of a bony HAGL. MRI or an MR arthrogram is the mainstay of diagnosis. The IGHL complex is best viewed on coronal oblique or sagittal oblique images on a T2-weighted MRI. In a normal shoulder, the IGHL complex forms a “U shape” at the inferior margin of the joint. In the presence of an RHAGL lesion, this is changed to a backward J shape as a result of the deficient capsule. Additionally, the use of an MR arthrogram can confirm the presence of an HAGL lesion. The axillary pouch of the IGHL drops inferiorly and extravasation of contrast media can be seen to cross the humeral attachment. While MRI is a helpful diagnostic tool, it has been shown to miss the diagnosis of an HAGL/RHAGL lesion in up to 50% of cases based on imaging alone. Conflicting pathology on MRI may distract from the HAGL diagnosis.

The arthroscopic repair of an RHAGL lesion can be performed in both the lateral decubitus and the beach-chair positions; however, we recommend the lateral position as it provides increased access and viewing of the inferior glenohumeral joint as compared to the beach-chair position. We perform most procedures for instability in the lateral decubitus position.

After successful induction of anesthesia, the patient is placed in the lateral decubitus position with the operative shoulder rolled posteriorly 30 to 45 degrees. An examination under anesthesia is performed to confirm preoperative clinical findings. Standard draping is applied and the arm is suspended (abducted 45–50 degrees, forward flexed 15–20 degrees) and attached to approximately 5 to 15 lb of weight (depending on the patient size).