**8.1 Examination under anaesthesia**

A meticulous examination under anaesthesia should be performed in all cases before arthroscopy. A sensitivity of 100% and specificity of 93% have been found for this examination as confirmed by the actual arthroscopic findings (Cofield et al, 1993). The examination should be performed either in the supine or beach chair positions. Passive range of motion is recorded first with the arm at the side and 90o of abduction. With the arm abducted at 90o, posterior and anterior forces are applied to provoke translation of the humeral head in relation to the glenoid. A sulcus sign is tested in adduction and external rotation, and also at 45o abduction that tightens the inferior capsule. Persistent sulcus sign in both positions is abnormal and indicative of rotator interval pathology.

### **8.2 Patient positioning**

The patient can be positioned in either the lateral decubitus or beach chair positions, which is mainly based on surgeon preference. The beach chair position affords several advantages including the ease to address concomitant rotator cuff pathology and the ability to convert to open surgery if necessary. However, it is often easier to address the pathology at the anteroinferior capsulolabral complex with the patient in the lateral decubitus position, because it provides a wider distension of the glenohumeral joint (Fig 6). The arm is usually placed at 45o abduction and traction is applied both in the axial and lateral directions. One of the disadvantages of this patient setup is the difficulty to achieve rotational control during the repair. For example, subscapularis repair and rotator interval closure are best performed in 30o to 45o of external rotation, which cannot be easily done at the lateral position.

#### **8.3 Instrumentation**

Basic equipment for shoulder arthroscopy includes a tower containing a video monitor, control box, light source, shaver power and electrocautery source, and irrigation pump. A

Arthroscopic Treatment of Recurrent Anterior Glenohumeral Instability 39

Fig. 7. Typical posterior, anterior-superior and anterior-inferior portals for arthroscopic anterior instability repair. A working cannula is inserted in the anterior-inferior and

Assessment of the mobility of the capsuloligamentous complex is crucial to determine if the soft tissues have been displaced or are scarred in a medial position on the neck of the glenoid. A combination of probes, rasps, motorized shavers and periosteal elevators are used to mobilize the medially displaced soft tissues from the glenoid neck. Care must be taken not to debride normal tissue needed for the repair. During this step, the subscapularis muscle must be visualized underneath the mobilized labral tissue. It is recommended to release tissue inferiorly to the 6 o'clock position on the glenoid face for optimal mobilization. Attention is then turned towards the glenoid. An abrader or rasp is used to decorticate the glenoid edge while preserving the bone stock. It is important to ensure that the soft tissue remnants have been removed and there is a bleeding bed of bone at the repair site to

A hole is created along the anterior and anteroinferior articular margin and the anchors are inserted below the articular surface. Accurate positioning of the anchors is critical to restore the depth of the glenoid. Ideally, the anchors are placed at 45o angle relative to the glenoid surface, perpendicular to the superior-inferior axis, and 2 to 3 mm inside the anterior glenoid rim (Fig 8). Eight to 10 mm intervals between the anchor holes are considered to

Glenoid anchors are commonly smaller than those used in rotator cuff repair because bone quality is usually better. Our current preference in our department is 2.8mm, absorbable,

The number and positioning of suture anchors used across the glenoid rim is still controversial. A standard arthroscopic Bankart repair typically requires three anchors. Others however have suggested the routine use of four anchors, because a three-anchor configuration was associated with increased failure rates (Boileau et al, 2006). Typically, the anchors are placed below the 3 o'clock position beginning inferiorly and then progressing superiorly. In general, it is acceptable to insert as many anchors as needed to achieve an adequate restoration of the capsulolabral restraint to anterior humeral head translation.

Wissinger rods in the remaining two portals.

**8.5 Glenoid and labrum preparation** 

enhance healing.

**8.6 Suture anchor placement** 

limit the stress risers for more secure fixation (Abrams, 2007).

screw-in anchors loaded with permanent, reinforced braided sutures.

30-degree arthroscope is usually adequate for most arthroscopic procedures in the shoulder. Fluid pressure within the joint should be kept around 30mmHg and may increase up to 70mmHg for viewing the subacromial space. Maintaining a systolic arterial pressure below 100mmHg improves visualization. Increased fluid pressure or flow may cause extravasation of fluid into the surrounding soft tissue, distort the anatomy intra-operatively and increase morbidity postoperatively.

Fig. 6. Lateral decubitus setup for arthroscopic instability repair. Axial and lateral traction is applied with the arm at approximately 45o abduction.

#### **8.4 Arthroscopic portals**

Initially, a standard posterior portal is used for diagnostic arthroscopy. It can be created in line with the lateral edge of the acromion and 1cm inferior to its posterior tip to have an improved trajectory in relation to the glenoid. This portal is used for diagnostic glenohumeral arthroscopy and to localize the pathology to be addressed. An anteriorsuperior portal is then created with an inside-out or outside-in technique between the biceps tendon and superior edge of the subscapularis. This portal is used for mobilization of the capsulolabral complex and for subsequent suture management. It is always advisable to assess the intra-articular pathology through the anterior-superior portal as well, to better evaluate the extent of labral tear posteriorly or glenoid bone loss and avoid missing a possible ALPSA lesion. A second anterior-inferior portal is placed just above the superior edge of the subscapularis to allow for inferior placement of suture anchors on the lower aspect of the glenoid neck. Both anterior portals are created within the rotator interval and there should ideally be enough skin bridge between them (2-3cm) to allow for easier handling of arthroscopic instruments (Fig 7). Alternative portals have been described, such as a transubscapularis portal described by Davidson and Tibone or a 7-o-clock posteroinferior portal for accessing the most inferior aspect of the glenoid.

Working cannulas are inserted into the two working portals to facilitate instrumentation handling. A wider (8mm) cannula is preferable for the anterior-inferior portal to allow for curved suture hooks, while a 5.5mm cannula is adequate for the superior portal for grasping instruments to be inserted.

Fig. 7. Typical posterior, anterior-superior and anterior-inferior portals for arthroscopic anterior instability repair. A working cannula is inserted in the anterior-inferior and Wissinger rods in the remaining two portals.

#### **8.5 Glenoid and labrum preparation**

38 Modern Arthroscopy

30-degree arthroscope is usually adequate for most arthroscopic procedures in the shoulder. Fluid pressure within the joint should be kept around 30mmHg and may increase up to 70mmHg for viewing the subacromial space. Maintaining a systolic arterial pressure below 100mmHg improves visualization. Increased fluid pressure or flow may cause extravasation of fluid into the surrounding soft tissue, distort the anatomy intra-operatively and increase

Fig. 6. Lateral decubitus setup for arthroscopic instability repair. Axial and lateral traction is

Initially, a standard posterior portal is used for diagnostic arthroscopy. It can be created in line with the lateral edge of the acromion and 1cm inferior to its posterior tip to have an improved trajectory in relation to the glenoid. This portal is used for diagnostic glenohumeral arthroscopy and to localize the pathology to be addressed. An anteriorsuperior portal is then created with an inside-out or outside-in technique between the biceps tendon and superior edge of the subscapularis. This portal is used for mobilization of the capsulolabral complex and for subsequent suture management. It is always advisable to assess the intra-articular pathology through the anterior-superior portal as well, to better evaluate the extent of labral tear posteriorly or glenoid bone loss and avoid missing a possible ALPSA lesion. A second anterior-inferior portal is placed just above the superior edge of the subscapularis to allow for inferior placement of suture anchors on the lower aspect of the glenoid neck. Both anterior portals are created within the rotator interval and there should ideally be enough skin bridge between them (2-3cm) to allow for easier handling of arthroscopic instruments (Fig 7). Alternative portals have been described, such as a transubscapularis portal described by Davidson and Tibone or a 7-o-clock

Working cannulas are inserted into the two working portals to facilitate instrumentation handling. A wider (8mm) cannula is preferable for the anterior-inferior portal to allow for curved suture hooks, while a 5.5mm cannula is adequate for the superior portal for grasping

posteroinferior portal for accessing the most inferior aspect of the glenoid.

applied with the arm at approximately 45o abduction.

morbidity postoperatively.

**8.4 Arthroscopic portals** 

instruments to be inserted.

Assessment of the mobility of the capsuloligamentous complex is crucial to determine if the soft tissues have been displaced or are scarred in a medial position on the neck of the glenoid. A combination of probes, rasps, motorized shavers and periosteal elevators are used to mobilize the medially displaced soft tissues from the glenoid neck. Care must be taken not to debride normal tissue needed for the repair. During this step, the subscapularis muscle must be visualized underneath the mobilized labral tissue. It is recommended to release tissue inferiorly to the 6 o'clock position on the glenoid face for optimal mobilization. Attention is then turned towards the glenoid. An abrader or rasp is used to decorticate the glenoid edge while preserving the bone stock. It is important to ensure that the soft tissue remnants have been removed and there is a bleeding bed of bone at the repair site to enhance healing.

#### **8.6 Suture anchor placement**

A hole is created along the anterior and anteroinferior articular margin and the anchors are inserted below the articular surface. Accurate positioning of the anchors is critical to restore the depth of the glenoid. Ideally, the anchors are placed at 45o angle relative to the glenoid surface, perpendicular to the superior-inferior axis, and 2 to 3 mm inside the anterior glenoid rim (Fig 8). Eight to 10 mm intervals between the anchor holes are considered to limit the stress risers for more secure fixation (Abrams, 2007).

Glenoid anchors are commonly smaller than those used in rotator cuff repair because bone quality is usually better. Our current preference in our department is 2.8mm, absorbable, screw-in anchors loaded with permanent, reinforced braided sutures.

The number and positioning of suture anchors used across the glenoid rim is still controversial. A standard arthroscopic Bankart repair typically requires three anchors. Others however have suggested the routine use of four anchors, because a three-anchor configuration was associated with increased failure rates (Boileau et al, 2006). Typically, the anchors are placed below the 3 o'clock position beginning inferiorly and then progressing superiorly. In general, it is acceptable to insert as many anchors as needed to achieve an adequate restoration of the capsulolabral restraint to anterior humeral head translation.

Arthroscopic Treatment of Recurrent Anterior Glenohumeral Instability 41

Capsular plication is an important aspect of correcting plastic deformation of the capsule. Sutures can be passed using suture hooks and shuttles along the posterior inferior labrum, anterior inferior pouch, and mid anterior capsule to reinforce the capsular thickness in vulnerable areas. These sutures can close defects, reinforce capsule thickness, and obliterate a pouch that developed as a result of capsular stretching. The capsule can be plicated either

Rotator interval closure is advisable when residual inferior translation is evident during the examination under anaesthesia or after Bankart repair. Typical Bankart repair does not require RI closure but may benefit from it. One or two sutures are passed from the middle glenohumeral ligament to the capsule anterior to the biceps tendon and tied. Consequently,

Associated SLAP tears are addressed simultaneously. Typical treatment of these lesions (type II and above) involves the placement of one or two suture anchors to reattach the superior labrum and biceps root to the glenoid rim. An accessory anterior portal is commonly created lateral to the biceps tendon within the rotator interval to provide the optimal approach angle for anchor insertion (Hantes et al. 2009). Alternatively, a transrotator cuff portal can be used. When the lesion extends to the posterior labrum a posterolateral acromial (Wilmington) portal is created 1cm anterior and 1cm lateral to the posterolateral edge of the acromion. After debridement of the superior glenoid and labrum, suture anchors are properly placed at the superior margin of the articular cartilage and

After all suture anchors are placed, the repair is evaluated from both the posterior and anterior portals (Fig 11). It is a good practice to remove the arm and evaluate the humeral head position and rotation, to best understand the tensioning effect of the repair. The head should appear well centered on the glenoid and any Hill-Sachs lesion should rotate posteriorly. Ideally, this lesion will not come in contact with the articular surface in any

Fig. 10. The arm of the braided suture has been passed through the labrum (left) and a

directly to the labrum or to itself.

sliding knot is being performed.

position of the shoulder.

the sides of this triangular interval are approximated.

sutures are tied as described above to restore all avulsed structures.

Fig. 8. Correct positioning of the suture anchor drill guide relative to the glenoid (left). The suture anchor has been inserted below the articular cartilage (right) with one arm facing the detached labrum.

Suture management is a challenge for arthroscopists performing reconstructive surgery. The anchors should be properly oriented to prevent unnecessary twists in the suture arms. Singleor double-loaded anchors may be used and should be inserted so that a single arm of the suture is facing the anticipated repair. A soft-tissue penetration device (suture passer or suture hook) is used to facilitate suture passage. We prefer to use a curved Spectrum suture hook (ConMed Linvatec, Largo, FL) and perform two separate passes though the capsule and then under the detached labrum towards the glenoid margin. A suture shuttle or a no1 monofilament suture is advanced through the hook and retrieved through the other working portal. The arm of the braided suture is passed through the eyelet of the shuttle or tied at the end of the monofilament suture and then pulled backwards to incorporate the piece of labrum and capsule (Fig 9). Sliding knots are then preformed and tied using a knot pusher and a knot cutter. The capsulolabral tissue is seen re-approximating the glenoid rim (Fig 10).

Fig. 9. Using a Spectrum suture hook, a PDS suture is passed (left) and tied (right) to the arm of the braided suture.

Fig. 8. Correct positioning of the suture anchor drill guide relative to the glenoid (left). The suture anchor has been inserted below the articular cartilage (right) with one arm facing the

Suture management is a challenge for arthroscopists performing reconstructive surgery. The anchors should be properly oriented to prevent unnecessary twists in the suture arms. Singleor double-loaded anchors may be used and should be inserted so that a single arm of the suture is facing the anticipated repair. A soft-tissue penetration device (suture passer or suture hook) is used to facilitate suture passage. We prefer to use a curved Spectrum suture hook (ConMed Linvatec, Largo, FL) and perform two separate passes though the capsule and then under the detached labrum towards the glenoid margin. A suture shuttle or a no1 monofilament suture is advanced through the hook and retrieved through the other working portal. The arm of the braided suture is passed through the eyelet of the shuttle or tied at the end of the monofilament suture and then pulled backwards to incorporate the piece of labrum and capsule (Fig 9). Sliding knots are then preformed and tied using a knot pusher and a knot

Fig. 9. Using a Spectrum suture hook, a PDS suture is passed (left) and tied (right) to the arm

cutter. The capsulolabral tissue is seen re-approximating the glenoid rim (Fig 10).

detached labrum.

of the braided suture.

Capsular plication is an important aspect of correcting plastic deformation of the capsule. Sutures can be passed using suture hooks and shuttles along the posterior inferior labrum, anterior inferior pouch, and mid anterior capsule to reinforce the capsular thickness in vulnerable areas. These sutures can close defects, reinforce capsule thickness, and obliterate a pouch that developed as a result of capsular stretching. The capsule can be plicated either directly to the labrum or to itself.

Fig. 10. The arm of the braided suture has been passed through the labrum (left) and a sliding knot is being performed.

Rotator interval closure is advisable when residual inferior translation is evident during the examination under anaesthesia or after Bankart repair. Typical Bankart repair does not require RI closure but may benefit from it. One or two sutures are passed from the middle glenohumeral ligament to the capsule anterior to the biceps tendon and tied. Consequently, the sides of this triangular interval are approximated.

Associated SLAP tears are addressed simultaneously. Typical treatment of these lesions (type II and above) involves the placement of one or two suture anchors to reattach the superior labrum and biceps root to the glenoid rim. An accessory anterior portal is commonly created lateral to the biceps tendon within the rotator interval to provide the optimal approach angle for anchor insertion (Hantes et al. 2009). Alternatively, a transrotator cuff portal can be used. When the lesion extends to the posterior labrum a posterolateral acromial (Wilmington) portal is created 1cm anterior and 1cm lateral to the posterolateral edge of the acromion. After debridement of the superior glenoid and labrum, suture anchors are properly placed at the superior margin of the articular cartilage and sutures are tied as described above to restore all avulsed structures.

After all suture anchors are placed, the repair is evaluated from both the posterior and anterior portals (Fig 11). It is a good practice to remove the arm and evaluate the humeral head position and rotation, to best understand the tensioning effect of the repair. The head should appear well centered on the glenoid and any Hill-Sachs lesion should rotate posteriorly. Ideally, this lesion will not come in contact with the articular surface in any position of the shoulder.

Arthroscopic Treatment of Recurrent Anterior Glenohumeral Instability 43

potentially causes permanent deficits. Intra-articular use of thermal devices, articular pain pumps, and local anesthetics within the articular space, as well as increased articular

Numerous pathologic conditions have been suggested as contraindications to arthroscopic shoulder instability repair, including capsular attenuation, humeral avulsion of the glenohumeral ligament (HAGL) lesions, failure of previous stabilization, and instability in a collision athlete. However, sizeable glenohumeral bone defects represent the most

Studies have shown that compression fractures of the posterior superior humeral head (Hill-Sachs lesion) can occur in 32% to 51% of initial anterior dislocations, while anteroinferior glenoid deficiency in 22% of primary dislocations (Rowe et al, 1978; Rowe et al, 1984). The incidence of both glenoid and humeral head bone defects approaches 100% in cases of

A critical decision on shoulder stabilization today focuses on the degree of bone loss and whether soft tissue reconstruction can be successful. Diagnostic pearls for clinical and imaging evaluation of glenohumeral bone defects have been discussed above. Bone defects between 20% and 30% of the inferior glenoid have shown a high recurrence rate after arthroscopic Bankart repair. However, the size and orientation of glenoid and humeral head defects can be extremely variable, making preoperative assessment and decision making difficult. It is currently suggested that patient with glenoid bone deficiency exceeding 20 to 25% of the articular surface should better be treated with a bone-substituting procedure

Bone grafting procedures, such as iliac bone-block or distal tibia transfer, glenoid allograft augmentation and the Bristow procedure have been advocated to restore osseous glenoid defects and shoulder stability. The Latarjet procedure was introduced in 1954. It delineates an osteotomy of the coracoid just proximal to its angle, which comprises the horizontal part of the coracoid and provides a 2 to 3cm bone segment. This is then transferred along with the attached conjoined tendon and the released coracoacromial ligament through a horizontal division of the subscapularis tendon and fixed at the antero-inferior glenoid,

The Latarjet procedure has shown excellent and reliable results both in biomechanical testing and the clinical setting. Quantitative Computed Tomography (qCT) has shown this technique to adequately restore a mean defect of up to 28% the intact inferior glenoid (Hantes et al, 2010). Compared with a structural bone graft, it resulted in significantly less anterior and anteroinferior translation at 60° of abduction. Satisfactory clinical results have also been reported with shoulder function ranging from good to excellent with recurrence rates between 0% and 7%. Complications include bony nonunion, graft displacement, progressive impingement and hardware loosening or migration. Improper graft placement, due to lack of experience or surgical exposure, may predispose to recurrent dislocation

pressure during surgery have been implicated in the pathogenesis of chondrolysis.

**9. Contraindications to arthroscopic instability repair** 

important contraindication to arthroscopic shoulder stabilization.

chronic anterior shoulder instability (Burkhart and De Beer 2000).

(when placed too medially or high) or osteoarthritis (too laterally).

**9.1 Glenohumeral bone defects** 

(Provencher et al, 2010).

preferably with two screws (Fig 12).
