Introduction

Significant bone loss, often characterized by an inverted-pear glenoid or engaging Hill-Sachs lesion, is believed to be a main cause of failures after arthroscopic stabilization.¹^–³ According to a three-dimensionally (3-D) reconstructed computed tomography (CT) study, the prevalence of glenoid bone defect has been reported as high as 90% in shoulders with chronic recurrent traumatic anterior instability, and an associated bony fragment is present in about half of shoulders with glenoid bone loss.⁴ Further, bone loss in shoulders associated with a bony fragment is relatively significant compared with that in shoulders with attritional glenoid without bony fragment.⁴^,⁵ Therefore, the majority of shoulders with a significant bone loss can be treated through arthroscopic bony Bankart repair.⁵

Indications/contraindications

• Surgery is indicated for patients who have symptomatic instability.

• Patients with uncontrolled epilepsy or who are noncompliant are not candidates for arthroscopic stabilization.

Preoperative history, examination, and radiographic findings

Preoperative history

The diagnosis of recurrent traumatic anterior glenohumeral instability is usually made easily on the basis of the history of distinct dislocation or subluxation and the positive apprehension sign. However, with collision athletes, care should be taken because they may not experience clear dislocation or subluxation and only complain of pain or weakness when they bring their arm to maximum external rotation in abduction.⁶

Examination findings

The anterior apprehension test is done with the patient in the supine position. In this test, the shoulder is moved passively into maximum external rotation with the arm at side; at 30, 60, 90, 120, and 150 degrees of abduction, and maximum flexion.⁶ At the same time, the posterior apprehension test is done with the arm at maximum internal rotation in 90 degrees of abduction. The feeling of apprehension is reported in each arm position. However, the most important and reliable physical examination usually can be done with the patient under anesthesia, comparing stability testing to the contralateral extremity.

Radiographic findings

X-ray images are sometimes helpful in detecting the Hill-Sachs lesion and the anterior glenoid rim lesion, especially during the first patient visit. Bernageau described a unique method for detecting an anterior glenoid rim lesion with the patients in the standing position.⁷ However, this technique requires fluoroscopic control in order to obtain optimal diagnosable images and, therefore, radiation exposure is an unignorable issue.⁸ We have developed a modified Bernageau method with the patient lying on their axilla in their most relaxed position (Fig. 15-1).⁶ In this method, clear Xx-ray images can be obtained more easily with a high probability of ascertaining bony pathology without using fluoroscopic imaging (Fig. 15-2).⁶

FIGURE 15-1 A modified Bernageau method. A, The patient lies on the axilla in the most relaxed position. In this position, the scapula needs to incline 5 degrees to the vertical line. B, Then the incident x-ray needs to be aimed craniocaudally with 15 to 20 degrees of inclination to the vertical line.

(From Sugaya H: Instability with bone loss. In Angelo R, et al, editors: AANA advanced shoulder arthroscopy, Philadelphia, 2010, Elsevier.)

FIGURE 15-2 X-ray images obtained by the modified Bernageau methods. A, Normal glenoid. B, Attritional glenoid. C, Bony Bankart.

(From Sugaya H: Instability with bone loss. In Angelo R, et al, editors: AANA Advanced shoulder arthroscopy, Philadelphia, Elsevier, 2010.)

Although plain magnetic resonance imaging (MRI) provides only limited information, magnetic resonance arthrography (MRA) is helpful when detecting a soft tissue lesion such as a Bankart lesion, capsular pathology, and/or a humeral avulsion of the glenohumeral ligament (HAGL) lesion. However, the final diagnosis of soft tissue pathology can be made most accurately through diagnostic arthroscopy.

Three-dimensional CT is the most important imaging study in assessing glenoid morphology accurately.⁴ In a shoulder with a bony Bankart, detecting accurate configuration of the bony fragment is not easy because the bone fragment is covered by the surrounding soft tissue. Through preoperative 3-D CT, surgeons can determine whether the glenoid is attritional or if a bony Bankart lesion is present. They also can quantify bone loss with attritional glenoids and detect the size and shape of the bony fragment in shoulders with a bony Bankart lesion (Fig. 15-3).⁴^,⁵^,⁹

FIGURE 15-3 A, A bony Bankart lesion in the 3-D CT images. Arthroscopic appearance of the bony Bankart lesion in the same shoulder viewed from the posterior (B) and the anterior portal (C). The asterisks indicate the bony fragment embedded in the surrounding soft tissue.

Description of techniques

If a bone fragment is present with 3-D CT, an arthroscopic bony Bankart repair, in which the fragment is incorporated into the Bankart repair, is indicated regardless of the severity of glenoid bone loss.⁵^,¹⁰^,¹¹ Therefore, a majority of shoulders with a large glenoid bone loss can be treated arthroscopically using this technique.⁶ For shoulders with significant bone loss associated with the attritional glenoids in young and active patients, although the number of such patients is limited, open or arthroscopic bone grafting procedures are indicated. The author’s preference is an arthroscopic iliac bone block grafting in combination with an anterior-inferior capsulolabral repair, which is described later in detail.¹²^,¹³

Arthroscopic bony bankart repair

Because most of the bony Bankart lesions are displaced and partly malunited chronic avulsion type fractures, the bony fragment is firmly connected to the adjacent labrum or soft tissue. These characteristics of chronic bony Bankart lesions make arthroscopic bony reconstruction feasible.⁵^,¹⁰ Normally, bony Bankart lesion is never completely healed to the glenoid neck because the fragment is displaced from the original place, and the adjacent glenohumeral ligament is not functioning. Therefore, most of the bony fragment associated with a bony Bankart lesion can be separated easily from the glenoid neck, using a standard straight rasp. Although the gap between the fragment and original glenoid is well demarcated in most shoulders, if otherwise, careful palpation or preoperative 3-D CT greatly helps surgeons to delineate the gap.⁶

In regard to patient positioning, all patients are seated in the beach chair position under general anesthesia, and joint laxity is assessed by examination of both shoulders before surgical intervention.

Procedure (see video 15-1)

• Step 1—Portals, Diagnostic Arthroscopy: A 4-mm arthroscope is introduced through a standard posterior portal, and a diagnostic arthroscopy is performed. We then create an anterior portal just superior to the subscapularis tendon and lateral to the conjoined tendon using an outside-in technique in order to facilitate instrument insertion without cannulas.¹⁴ Inserting the arthroscope through the anterior portal also can help confirm a bony Bankart lesion (see Fig. 15-3).

• Step 2—Mobilization of the Complex: After inspection from the anterior portal, separation and mobilization of the labroligamentous complex together with the bony fragment from the glenoid neck is performed using an elevator, straight and curved rasps, scissors, shavers, and a radiofrequency instrument through a cannula-less anterior portal. This step is a vital part of this procedure. First, a straight rasp is inserted from the anterior portal and is placed in the small gap between the fragment and the glenoid neck. Then, the gap is expanded by tapping the handle of the rasp. After separating the fragment from the glenoid neck, the mobilization of the labroligamentous complex is performed up to the 7:30 position in the right shoulder until the complex and the fragment become completely free in exactly the same way as one would mobilize a Bankart lesion without a bony fragment using the instruments previously described. Once mobilization of the fragment and the complex are completed, preparation of the glenoid is performed by removing scar tissues from the glenoid neck and exposing the bony surface using a shaver and an abrader. Further, articular cartilage on the edge of the glenoid also is removed to promote tissue healing after repair (Fig. 15-4). Normally, the separation of the fragment from the neck can be readily accomplished using only elevators and rasps. If the separation of the fragment is difficult and the fragment is united firmly, a small size chisel can be introduced from the anterior portal to separate it from the glenoid neck. An anterosuperior portal is established at the anterosuperior margin of the rotator interval using an outside-in technique. This becomes the second working portal. In shoulders with superior labral detachment, a lateral acromial portal, established just lateral to the midpoint of the acromion through the muscle-tendon junction of the infraspinatus, is used instead of the anterosuperior portal (Fig. 15-5).

• Step 3—Repair of Inferior Labrum Adjacent to the Osseous Fragment: The first bioabsorbable suture anchor loaded with #2 high-strength suture is inserted on the surface of the glenoid at the 6 o’clock position using a drill guide introduced through the anterior portal. Because this portal has no cannula, the angle of approach of the guide can be adjusted easily allowing optimization of the angle to the glenoid.¹⁴ After the first anchor insertion, a looped #2-0 nylon suture is placed into the labrum at the 6:30 position using a low profile 7-mm Caspari Punch (Conmed Linvatec, Largo, FL) or a Suture Hook (Conmed Linvatec, Largo, FL). A suture relay is then performed intra-articularly.¹⁴ The second anchor is inserted into the face of the glenoid at the 4:40 position, followed by the suture placement in the labrum adjacent to the inferior side of the bony fragment using the same technique (Fig. 15-6). After completion of the suture placement of the inferior two anchors, knot tying is performed using a self-locking sliding knot through a 5-mm cannula inserted through the anterior portal. To accomplish secure knot tying, the complex, together with the fragment, is held upward and laterally on the glenoid surface by a grasper introduced through the anterosuperior portal to reduce tensile force on the suture (see Figs. 15-6 and 15-7).

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