Arthroscopic Bankart-Bristow-Latarjet (2B3) Procedure: How to Do It and Tricks To Make it Easier and Safe

The all-arthroscopic technique that the authors propose combines a Bristow-Latarjet procedure with a Bankart repair. This combined procedure provides a triple blocking of the shoulder (the so-called 2B3 procedure): (1) the labral repair recreates the anterior bumper and protects the humeral head from direct contact with the coracoid bone graft (Bumper effect); (2) the transferred coracoid bone block compensates for anterior glenoid bone loss (Bony effect); and (3) the transferred conjoined tendon creates a dynamic sling that reinforces the weak anteroinferior capsule by lowering the inferior part of the subscapularis when the arm is abducted and externally rotated (Belt or sling effect). The procedure combines the theoretic advantages of the Bristow-Latarjet procedure and the arthroscopic Bankart repair, eliminating the potential disadvantages of each. The extra-articular positioning of the bone block together with the labral repair and capsule retensioning allows the surgeon to perform a nearly anatomic shoulder repair. This novel procedure allows the surgeon to extend the indications of arthroscopic shoulder reconstruction to the subset of patients with recurrent anteroinferior shoulder instability with glenoid bone loss and capsular deficiency. It is an attractive surgical option to treat patients with a previous failed capsulolabral repair for which the surgical solutions are limited.

Technical advancements in arthroscopic shoulder surgery in the last 2 decades have dramatically altered the treatment of anterior shoulder instability. Arthroscopic labral repair, once considered an ineffective and impractical procedure is now considered routine and reliable, and in most situations is the treatment of choice for recurrent anterior shoulder instability.

Although the results of arthroscopic anterior labral repair using modern techniques have been shown to approach the success rates of open anterior stabilizations in most patients, it has been recognized that it is much less effective in patients with risk factors for failure such as young age, hyperlaxity, competitive contact sport participation, and particularly severe glenoid or humeral bone loss. In such patients coracoid transfer procedures have been shown to be more effective.

This recognition combined with the trend toward minimally invasive shoulder surgery and incremental improvements in technology and technique have led some surgeons to push the boundaries of arthroscopic treatment even farther, developing techniques to treat severe instability with associated bone loss using arthroscopic coracoid transfer. This approach may seem fanciful and impractical to many surgeons today, just as arthroscopic labral repair did 20 years ago. However, it is our belief that the rationale for the procedure is sound and that it provides certain advantages over the traditional open coracoid transfer procedures. Once certain technical challenges are overcome the authors believe that it will become a reliable and commonly performed procedure.

Background

The open Bristow-Latarjet coracoid transfer, proposed as an alternative to capsulolabral repair in patients with significant glenoid bone loss, has been shown to be a reliable technique with a very low rate of recurrent instability, a high rate of return to sports at the preinjury level and a high rate of patient satisfaction. However, placement of the transferred coracoid graft may be difficult because of the limited exposure, especially in young muscular athletes. Improper surgical placement of the coracoid bone block and screw failures are common complications, which have been reported in up to 50% of patients, and may compromise the results of the procedure. A coracoid bone block placed too medial or too high (over the glenoid equator) has been found to be associated with recurrent shoulder instability; late glenohumeral osteoarthritis may result from lateral placement of the bone block.

In recent years the concept of performing the Bristow-Latarjet transfer procedure under arthroscopy has emerged. Our experience with an arthroscopic modified Bristow procedure started 10 years ago with the Bristow-Trillat procedure, which consists of an arthroscopic Bankart repair combined with a transfer of the tip of the coracoid process to a socket drilled in the glenoid neck over the subscapularis. The authors have reported the results of this procedure, which supplements the Bankart repair with the sling effect of the conjoined tendon and allows stabilization of shoulders in hyperlax patients. However, in patients with glenoid bone loss, the bone block effect is also needed, which means that the coracoid tip must be passed through the subscapularis muscle and fixed on the glenoid neck. Such a procedure is technically more difficult to perform arthroscopically.

Lafosse and colleagues have recently proposed an arthroscopic technique similar to the original technique described by Latarjet in 1954. In this technique, the labrum and capsule are resected and the bone block is therefore positioned inside the glenohumeral joint. We have developed an all-arthroscopic approach that is different in at least 2 respects: (1) we do not resect the labrum and capsule but, instead repair them with suture and anchors; and (2) we place the bone block in the standing position outside the glenohumeral joint.

The goal of our all-arthroscopic technique is to provide a nearly anatomic reconstruction of the glenohumeral joint by treating the soft tissue and the bony lesions, as well as to reinforce the weak anteroinferior capsule with the help of a musculotendinous sling. Our technique, which combines a Bristow-Latarjet coracoid transfer procedure with a Bankart repair, has been developed on cadaveric specimens by the senior author after 20 years of experience with the open technique. It provides a so-called triple-blocking effect ( Fig. 1 ): (1) the labral repair recreates the anterior bumper and protects the humeral head from direct contact with the coracoid bone graft (bumper effect); (2) the transferred standing coracoid bone block compensates for anterior glenoid bone loss and conforms to the glenoid concavity (bony effect); and (3) the transferred conjoined tendon creates a dynamic reinforcement of the inferior part of the capsule, by itself and by lowering the inferior part of the subscapularis, particularly when the arm is abducted and externally rotated (belt or sling effect). Our hope is that, by doing so, we can avoid some of the common complications reported with the standard Bristow-Latarjet procedure, such as residual instability (apprehension or subluxations), persistent shoulder pain, or glenohumeral osteoarthritis.

Surgical technique

The patient is placed in the semi-beachchair position with the trunk elevated 30°. The arm is placed parallel to the floor in a support (Spider limb positioner, Tenet Medical, Canada) without traction.

In addition to the standard posterior portal, 5 anterior portals are used. Their locations are carefully marked on the skin ( Fig. 2 A). The central portal is located just lateral to the tip of the coracoid; the proximal portal (or north portal) is located above the coracoid process, just in front of the acromioclavicular joint; the distal portal (or south portal) is located in the axillary fold, 3 finger widths distal to the tip of the coracoid; the lateral portal (or west portal) is located 2 finger widths lateral to the tip of the coracoid; and the medial portal (or east portal) is located 3 to 4 finger widths medial to the tip of the coracoid, passing obliquely through the pectoralis major muscle (see Fig. 2 B). Before starting, the soft tissues (skin, fat, and deltoid fascia) are elevated from the coracoid process and conjoined tendon by injecting 10 mL of xylocaine with adrenaline.

The surgical technique is comprised of 5 operative steps, all performed arthroscopically.

Step One: Glenoid Preparation and Drilling

With the arthroscope in the posterior portal, the rotator interval is opened using a radiofrequency device (VAPR, Depuy-Mitek, USA), and the coracoid process and conjoined tendon are identified. The anterior labrum is completely detached until the red fibers of the subscapularis muscle are clearly seen. A traction suture is passed through the labrum and used at the time of the Bankart repair to manipulate and shift it proximally. The anterior glenoid rim is debrided from 2 to 6 o’clock with a shaver and a burr. The scope is switched to the anterior central portal. A specific guide (glenoid guide, Smith & Nephew, USA), introduced through the posterior portal, is used to insert a guide pin through the glenoid neck from posterior to anterior. The glenoid guide is angled 15° from medial to lateral and has a stop at the distal end to prevent over-penetration of the guide pin ( Fig. 3 A). The guide pin is made of 2 parts: a female part (2.8 mm in diameter) and a male part (1.5 mm in diameter). The guide pin should penetrate the glenoid neck anteriorly below the equator (at 5 o’clock) and 3 mm medial to the glenoid surface (see Fig. 3 B). The drilling depth is measured using the glenoid guide. Before leaving the glenohumeral joint a blunt switching stick is introduced through the posterior portal and pushed through the subscapularis muscle (under the labrum) to act as a landmark for the subscapularis split that will be performed later.

Step 2: Coracoid Harvesting

The scope is then placed in the anterior subdeltoid space through the lateral (west) portal and the coracoid process and subcapularis are identified, still using the VAPR. The distal (south) portal and medial (east) portal are created, using an outside-in technique with a blunt trochar directed to the tip of the coracoid process. When creating the east portal, care should be taken to keep the instruments superficial to the conjoined tendon to avoid injury to the brachial plexus and axillary vessels. The coracoacromial ligament is released from the lateral side of the coracoid and the pectoralis minor insertion is released from its medial side. Because the brachial plexus lies just behind the pectoralis minor, the VAPR device is kept strictly in contact with the medial side of the coracoid. The pectoralis minor and conjoined tendon are confluent at this level and should be separated with the VAPR, but only over a limited distance of 10 to 15 mm to prevent injury to the musculocutaneous nerve and preserve the vascular pedicle of the coracoid graft.

Using a specific guide (coracoid guide, Smith & Nephew, USA), introduced through the distal (south) portal, a guide pin is inserted along the axis of the coracoid process ( Fig. 4 A). The coracoid is drilled along its axis using a cannulated drill. A 3.5-mm cannulated screw is then inserted centrally in the coracoid to a depth of 15 mm (see Fig. 4 B). The length of the screw that is selected is determined by adding the length of the coracoid graft to the glenoid drilling depth previously measured, and adding 2 mm to ensure that the posterior cortex is engaged.

The proximal (north) portal is then created just anterior to the acromioclavicular joint using a spinal needle to ensure it is strictly perpendicular to the coracoid process. The coracoid is held using a grasper introduced through the central portal. Starting on its superior surface, the coracoid is osteotomized 15 mm from the tip using a zip burr or a saw via the proximal (north) portal. When half of the osteotomy is completed, the central location of the guide pin and screw is confirmed. The guide pin is then retrieved but the screwdriver is left in place. A metallic suture-passing wire is introduced through the screwdriver, screw, and bone block and retrieved through the medial (east) portal. The coracoid osteotomy is then completed in an oblique fashion, leaving more bone superiorly than inferiorly so that the cancellous surface of the bone block has an oblique shape matching the anterior glenoid neck.

Still holding the coracoid with the coracoid grasper, the screw is pushed further through the bone block. The screwdriver is disengaged from the screw and the other end of the suture-passing wire is retrieved with a grasper, also through the medial (East) portal. By pulling on both strands of the metallic wire from the medial (east) portal the bone block is flipped and medialized, thus giving free access to the subscapularis muscle belly.

Step 3: Axillary Nerve Identification and Subscapularis Splitting

At this stage of the procedure, the arm is placed in flexion and slight internal rotation to identify the axillary nerve. Using a blunt trocar, the nerve is located as it passes under the inferior rim of the subscapularis ( Fig. 5 A). The arm is then placed in neutral rotation to provide better access to the muscular part of the subscapularis. The bursa and fascia are removed from the anterior surface of the subscapularis muscle. Once the superior border of the subscapularis and its inferior border with the anterior axillary vessels (the 3 sisters) are identified, the switching stick is pushed fully through the subscapularis muscle. Using the VAPR via the medial (east) portal, the subscapularis muscle belly is then split in line with its fibers at the superior two-thirds and inferior one-third junction (at the level of the switching stick). The VAPR is moved from medial to lateral, away from the axillary nerve, which remains under constant visual control medially (see Fig. 5 B). Hemostasis is carefully maintained as division of the muscle is slowly carried down to the glenoid neck.

A small U-shaped retractor is inserted in the subscapularis split via the proximal (north) portal and used to retract the upper part of the subscapularis superiorly. A second retractor is introduced through the distal (south) portal and placed under the neck of the scapula between the capsule and the subscapularis to retract the lower part of the muscle inferiorly ( Fig. 6 A). The lower part of the glenoid neck is exposed and the previously inserted glenoid guide wire is identified. To improve visualization of the anterior neck, the arthroscope can be then transferred to the distal (south) portal (together with the inferior retractor). Correct positioning of the pin is confirmed: below the equator and 3 mm medial to the glenoid surface. Decortication of the glenoid neck is completed using a burr, and a 2-mm deep socket created to receive and stabilize the bone block.

Step 4: Coracoid Transfer and Fixation

A swivel tip screwdriver is introduced via the medial (east) portal along 1 strand of the metallic wire (the one without the loop) and engaged in the previously placed screw. A suture is placed trough the metallic loop and a knot pusher is introduced via the medial (east) portal over the suture to bring the wire’s loop inside the shoulder. By pulling on the end of the metallic wire, the loop is brought to the tip of the screw. The screwdriver and the knot pusher are used to guide the bone block and wire’s loop toward the glenoid neck. A hooked suture retriever (Captain Hook, Smith & Nephew, USA) is passed from posterior to anterior through the female guide pin and used to catch the loop and retrieve the metallic wire posteriorly (see Fig. 6 B). Once the loop is caught by the hook, the knot pusher and suture are removed. By pulling on the Captain Hook, the nitinol wire is brought to the posterior aspect of the shoulder. Once the wire is retrieved posteriorly the female guide pin is removed using a pin puller. Two Kocher forceps are then clipped on each end of the nitinol wire (flush to the handle of the screwdriver anteriorly and flush to the skin posteriorly) to prevent disengagement of the screwdriver from the screw. With the subscapularis split maintained open with retractors and switching stick, the bone block and screw are guided into place on the glenoid neck by applying gentle traction on the suture-passing wire posteriorly and using the screwdriver as a joystick anteriorly. The switching stick can also be used as a lever to lift up the upper two-thirds of the subscapularis.

The screw is advanced through the bone block and into the hole in the glenoid neck guided by the metallic wire ( Fig. 7 A). After engaging the screw to a depth of approximately 10 mm, the scope is reintroduced into the glenohumeral joint through the posterior portal (using the switching stick) to obtain an intra-articular view. Pulling on the traction suture helps to lift up the labrum and capsule to visualize the bone block from inside the joint. A grasper or spatula is introduced through the anterior central portal and used to rotate the coracoid graft 90° so that its concave surface conforms to the natural convexity of the glenoid. Compression of the bone block is controlled by direct visualization and any soft tissue interposed between the bone block and the glenoid neck is removed. Accurate initial positioning of the guide wire allows the bone block to be positioned flush to the glenoid surface and below the equator (see Fig. 7 B).

Step 5: Capsulolabral (ie, Bankart) Repair

Still with the scope in the posterior portal, a classic arthroscopic Bankart repair is performed using 2 to 3 suture anchors (Lupine anchors or Knotless anchors, Depuy-Mitek, USA). The anchors are placed on the glenoid rim at 5, 4 and 3 (or 2) o’clock, which allows retensioning of the capsuloligamentous structures and recreation of the bumper effect of the labrum. The scope is reintroduced through the anterolateral (west) portal to observe the sling effect of the conjoined tendon passing through the subscapularis muscle. Range of motion is checked to ensure that complete mobility is maintained. The coracoid with the attached conjoined tendon maintains the subscapularis split open and no attempt is made to close the split because this would limit rotation. Postoperative radiographs are taken to confirm the correct positioning of the bone block ( Fig. 8 A–C).