TECHNIQUE
Arthroscopic Latarjet and Capsular Shift (ALCS) Procedure: A New “Freehand” Technique for Anterior Shoulder Instability Associated With Significant Bone Defects Deepak N. Bhatia, MS(Orth), DNB(Orth)
Abstract: Anterior shoulder instability associated with significant bone loss has been described as “bony-instability,” and this condition is usually treated with an anterior glenoid bone grafting procedure (Latarjet procedure). The Latarjet procedure involves transfer of the horizontal limb of the coracoid process along with the conjoint tendon to the anterior glenoid rim, and is traditionally performed as an open surgical procedure. Recently, an arthroscopic technique for the Latarjet procedure has been described; the technique necessitates the use of specialized instrumentation and involves excision of the entire anterior capsule to facilitate coracoid fixation. We describe a new “freehand” arthroscopic technique for the Latarjet procedure, and, in addition, a simultaneous capsular shift to further optimize mid and end range stability. This technique eliminates the use of additional instrumentation and can be done using routine arthroscopic instruments. Preliminary experience with this technique suggests that the arthroscopic Latarjet and capsular shift is a technically demanding procedure. Glenohumeral capsule can be preserved, and this should be attempted wherever possible to optimize stability. Additional specialized instrumentation would probably reduce surgical time; however, the procedure can be performed with routine instruments. Key Words: Latarjet procedure, capsular shift, shoulder arthroscopy, shoulder instability (Tech Hand Surg 2015;19: 11–17)
HISTORICAL PERSPECTIVE The Latarjet procedure (open and mini-open) is a well recognized and accepted technique for surgical treatment of anterior instability associated with significant bone defects. The procedure involves transfer of the coracoid process to the anterior glenoid for reconstruction of the glenoid bone loss. The procedure was first described by Latarjet in 1955, and several modifications have evolved thereafter.1,2 Recently, Lafosse and Boyle have described an arthroscopic technique for the Latarjet procedure for safe and reproducible coracoid fixation to the deficient anterior glenoid. The authors reported excellent results in a large series of patients using this technique.3 The procedure involves excision of the entire anterior glenohumeral capsule to permit adequate visualization and to facilitate graft passage without obstruction. The procedure is performed with special instrumentation (Mitek) that simplifies the procedure and makes it reproducible and safe. A modification of the arthroscopic Latarjet procedure has been described, and this technique also involves excision of the anterior capsule.4 From the Department of Orthopaedic Surgery, Seth GS Medical College, and King Edward VII Memorial Hospital, Mumbai, India. Conflicts of Interest and Source of Funding: The authors report no conflicts of interest and no source of funding. Address correspondence and reprint requests to Deepak N. Bhatia, MS(Orth), DNB(Orth), Department of Orthopaedic Surgery, Seth GS Medical College, and King Edward VII Memorial Hospital, Parel, Mumbai 400012, India. E-mail: [email protected]. Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved.
Techniques in Hand & Upper Extremity Surgery
The role of preservation of the anterior capsule has been analyzed in biomechanical and clinical studies, and closure of the capsule has recently been described as an important component of the Latarjet procedure. Young et al2 described the use of the coracoacromial (CA) ligament to reconstruct the anterior capsule. Burkhart and DeBeer5 described the congruent-arc modification with an added capsular shift for greater stability. Hovelius et al6 showed a significantly better outcome in Latarjet procedure with capsular repair. Bhatia and DasGupta found an 11% incidence of humeral avulsion glenohumeral ligament lesions (HAGL) associated with significant glenoid defects, and described excellent results with a new dual-window subscapularis-sparing approach for combined Latarjet procedure, capsular shift, and HAGL lesion repair.7,8 Biomechanical studies have further quantified the role of capsular closure in this procedure. Schulze-Borges and colleagues compared open and arthroscopic Latarjet procedure, and found a superior stabilization effect of the open Latarjet procedure in a pure abduction position of the arm, as compared with the arthroscopic Latarjet. They ascribed this difference to anterior capsular repair, which was performed in the open technique, and omitted during the arthroscopic procedure.9 Wellmann et al10 investigated the biomechanical status of different components of the Latarjet procedure, and concluded that anterior capsule reconstruction represented a significant contribution to the stabilizing effect of the Latarjet procedure. Yamamoto et al11 found that anterior capsular closure contributed to approximately 25% of the end range stability. We describe a new arthroscopic Latarjet technique that involves coracoid transfer and capsular shift. The entire anterior capsule is detached initially, and is reattached to the glenoid rim after coracoid fixation, thereby exteriorizing the bone graft. The procedure is performed with routine arthroscopic instruments, and may, therefore, be used even when special instrumentation is unavailable.
INDICATIONS The arthroscopic Latarjet and capsular shift (ALCS) procedure is performed in anterior glenohumeral instability associated with significant bony defects (> 20% to 25% glenoid loss).7 Balg and Boileau12 have described an Instability Severity Index Score, and a score of 6 or greater necessitates a bone grafting procedure like the ALCS. Larger “engaging” Hill-Sachs lesions without glenoid loss are relative indications, although these lesions may also be treated with a “remplissage” procedure.13 In some patients, poor capsular tissue may preclude an effective soft tissue repair, and an ALCS procedure may be indicated.
CONTRAINDICATIONS The ALCS procedure is relatively contraindicated in patients with no bone defects, and strong capsular tissue. The only exception to this is contact athletes. The procedure should be performed with caution in patients with poor bone mineral
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colleagues. The coracoid and screw portals are created with a 5 mm stab incision, and the drilling, osteotomy, and screw passage is percutaneous without the use of a large diameter cannula. A diagnostic arthroscopy is performed by the standard posterior portal; the glenoid and humeral bone defects are visualized and quantified. Any associated soft tissue lesions (superior labral tears, HAGL lesions) are noted and may be treated at this stage.7 Thereafter, the ALCS procedure can be simplified into the following 7 steps:
Step 1: Capsulotomy and Capsular Preservation FIGURE 1. Arthroscopic shoulder portals are shown. V1 and V2 are anterolateral viewing portals. C1 and C2 are percutaneous coracoid drilling portals. S1 and S2 are percutaneous coracoid fixation portals.
density and patients with relatively smaller coracoid processes; these are prone to graft breakage and suboptimal screw purchase, and may result in intraoperative complications.
SURGICAL TECHNIQUE Positioning and Portals The patient is placed in a high beach-chair position (60 to 80 degrees), and the shoulder is draped with adequate anteromedial clearance; this position facilitates medial portal placement for graft fixation. A standard posterior viewing portal (1 to 2 cm medial and inferior to the posterolateral acromial angle) is placed in the standard “soft spot.” A standard anterior portal (A) is placed in the rotator interval. Additional portals include V1 and V2 (viewing portals), C1 and C2 (portals for coracoid drilling and osteotomy), S1 and S2 (portals for screw fixation) (Fig. 1). These portals have been modified from the original arthroscopic Latarjet procedure described by Lafosse and
This is the most important difference between the ALCS and other modifications of the arthroscopic Latarjet procedure. The capsulotomy is initiated at the rotator interval, and a transverse excision of rotator interval capsule is performed. The capsulolabral complex is then dissected from the anterior glenoid rim using a radiofrequency (RF) probe tip, or arthroscopic scissors, by the standard anterior portal (A). The capsulotomy is extended down to the 6 o’clock position on the glenoid, and care is taken to limit dissection to the bonelabrum junction. Next, the capsule is separated from the subscapularis muscle using blunt dissection. This maneuver preserves both capsular and subscapularis fibers, and does not compromise vascularity and innervation. Adequate mobility of the capsule is confirmed by grasping the capsule and checking medial approximation to glenoid rim (Figs. 2A–E).
Step 2: Coracoid Exposure Coracoid dissection is performed with a shaver and RF probe by the standard anterior portal (A) and V1. The coracoacromial ligament (CA) and conjoint tendon (CT) are identified the CA attachment to the coracoid process is separated, and the tendinous fibers of the CT, covering the coracoid tip, are preserved. Next, the clavipectoral fascia (CL) lateral to the CT is cut for approximately 4 to 5 cm inferior to the coracoid tip.
FIGURE 2. Surgical steps for capsulotomy and capsular preservation are shown. A, Anterior significant glenoid bone loss can be visualized. B, The capsule is shown after separation from the anterior glenoid rim. The underlying subscapularis fibers can be visualized. C, The capsule is separated from the underlying subscapularis muscle. D, The capsule is retracted laterally and the subscapularis fibers are visible. E, The capsule is grasped and approximated to the anterior glenoid rim to ascertain mobility. Cp indicates capsule; G, glenoid, H, humeral head; SSc, subscapularis; Gr, grasper.
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Arthroscopic Latarjet and Capsular Shift (ALCS) Procedure
FIGURE 3. A, Arthroscopic dissection of the coracoid attachments is shown. The coracoacromial ligament (CA) is visualized as a glistening white structure attaching to the superior surface of the coracoid (Co). The conjoint tendon (CT) attaches to the coracoid tip. The clavipectoral fascia (CL) extends laterally from the tendinous edge of the conjoint tendon. B, The pectoralis minor tendon (Pm) is separated from the medial coracoid surface (Co). C, Medial dissection under the pectoralis minor muscle (Pm) reveals a constant fat pad (FP), and the brachial plexus (BP) underneath. Co indicates coracoid process; RF, radiofrequency probe; ssc, subscapularis tendon.
The arthroscope is now shifted to the V1 portal, and a V2 portal is created adjacent to the coracoid tip. The RF probe is placed in the V2 portal, and the pectoralis minor (PM) is exposed and dissected off the medial border of the superior coracoid pillar. A constant fat pad is identified deep to the PM and further medial dissection is not necessary. The brachial plexus (BP) is medial to this fat pad, and blunt dissection in this region will usually identify the musculocutaneous nerve. The CT is released from the medial fascia for 2 to 4 cm below the coracoid tip. The superior surface of the coracoid process is cleared up to the trapezoid ligament, and a constant ridge, just anterior to this ligament, serves as a guide to the trapezoid ligament and subsequent osteotomy (Figs. 3A–C).14
Step 3: Coracoid Drilling Coracoid drilling is performed by percutaneous portals C1 and C2. These are located using needles, and a 3.5 mm guide cannula is placed through the percutaneous portals. Wires for cannulated drill system are passed through the superior coracoid surface, and exit through the undersurface under vision. A 3.2 mm cannulated drill bit is passed over the wires and drill holes are completed. This method of “freehand”
placement of drill holes allows for precise placement of 2 holes even in smaller coracoids, as compared with standard drill guides, which only allow a fixed distance between the screws. The undersurface of the coracoid is prepared at this stage; arthroscopic burrs and a rasp (PoweRasp, Arthrex) are used to lightly decorticate the coracoid undersurface for later fixation (Figs. 4A–C).
Step 4: Coracoid Osteotomy Two 5 mm narrow osteotomes are placed on the superior and inferior surfaces of the superior coracoid pillar. The superior osteotome (OS1) is placed percutaneously through the C1 or C2 portals, and the inferior osteotome (OS2) is placed through a 6 mm cannula in portal V2. This approach provides the correct angles for the osteotomy, and preserves bone in smaller coracoids. A constant ridge between the junctional surface area and superior coracoid pillar serves as a guide and the osteotomy must be limited to this level to prevent inadvertent damage to the coracoclavicular ligaments.14 The osteotomy approach also prevents extension of the osteotomy into the drill holes, which may happen if a burr is used for osteotomy (Fig. 5).
FIGURE 4. Percutaneous coracoid drilling is shown. A, Guide wires (W1 AND W2) are placed through percutaneous cannulas by coracoid portals. B, The exact points for drilling the guide wires is ascertained using spinal needles (C1, C2) after coracoid (Co) exposure. C, The coracoid process (Co) is drilled using a cannulated drill-bit (DR) over the guide wire (G). Inferior migration of the guide wire is prevented by placing a shaver blade (B) under the guide wire. SH indicates arthroscope sheath; CT, conjoint tendon; V1 and V2, anterolateral viewing portals; S1 and S2 are percutaneous coracoid fixation portals. Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved.
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performed with caution to avoid damaging the preserved anterior capsule, and the long biceps tendon (Figs. 6A, B).
Step 6: Coracoid Fixation
FIGURE 5. Coracoid osteotomy is performed using 2 curved osteotomes (OS1 and OS2) placed through C1/C2 portal and V2 portal. V1 and V2 are anterolateral viewing portals. C1 and C2 are percutaneous coracoid drilling portals. S1 and S2 are percutaneous coracoid fixation portals.
Step 5: Subscapularis Split The anterior surface of the subscapularis is cleared down to the leash of the anterior circumflex vessels. A Wissenger rod is passed into the glenohumeral joint through the posterior portal, and through the subscapularis; the passage is performed before the coracoid osteotomy and is lateral to the CT, at the midpoint between the upper subscapularis border and leash of vessels. The subscapularis is split using the RF probe, and the Wissenger rod is used to lever the subscapularis superiorly, thereby facilitating the split. The split should be restricted medially up to 10 mm from the anterior glenoid rim to protect the subscapularis nerves.15 Laterally, the split should be
An outside-in technique is used to create 2 medial portals S1 and S2, these portals are guided by the posterior Wissenger rod that was passed through the subscapularis, and should have a trajectory as parallel as possible to the glenoid articular surface. A guide wire is passed through the superior cannula and is directed approximately 5 mm medial to the glenoid articular surface on the anterior glenoid neck just below the 2 o’clock position. A long 3.2 mm cannulated drill bit is used to drill this hole through both cortices; the wire and drill bit are withdrawn, and a depth gauge is used to measure the length of the hole. A wire is now reinserted through the cannula into the upper coracoid hole, and directed into the glenoid drill hole. The cannula is withdrawn, and a 4 mm cannulated cancellous screw with a washer is passed percutaneously into the coracoid graft. The screw is advanced over the wire into the glenoid; further tightening leads to an indirect reduction of the coracoid onto the glenoid, and the subscapularis fibers are retracted superiorly just before intra-articular entry of the graft. Thereafter, a second wire is placed through portal S1 or S2 into the coracoid and glenoid, and the steps are repeated to place a second screw for graft fixation. Final tightening is performed simultaneously with 2 screwdrivers to achieve graft compression (Figs. 7A–E and 8).
Step 7: Capsular Shift and Graft Exteriorization Capsular shift of the preserved anterior capsule is performed by viewing through the standard posterior portal, and working through the V1 and A portals (Fig. 9). The capsule is grasped and approximated to the glenoid to determine the integrity and tissue tension. Usually, the anterior band of the inferior glenohumeral ligament is well preserved, and is used to anchor the capsular tissue to the glenoid. One or 2 double-loaded anchors are passed through the V1 portal into the 4 and 2 o’clock positions on the anterior glenoid rim. An antegrade or retrograde suture passing device is used to pass sutures through the capsule in a mattress manner. Thereafter, sliding knots (double-barrel knot) are tied in 20 to 30 degrees of external rotation to approximate the capsule to the glenoid.16 The capsular closure completely covers the coracoid graft and exteriorizes it.
FIGURE 6. Steps for splitting the subscapularis muscle are shown. A, A Wissenger rod (G) passed through the posterior portal and through the subscapularis (SSC) lateral to the conjoint tendon. B, The subscapularis is split from medial to lateral at the level marked by the rod. H indicates humeral head; GL, glenoid; RF radiofrequency probe.
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Arthroscopic Latarjet and Capsular Shift (ALCS) Procedure
FIGURE 7. A guide wire G is placed through one of the coracoid (Co) holes (7A) and passed through a predrilled glenoid hole (7B). C, Percutaneous cannulated screw (Cn) passage is shown over guide wires G1 and G2 through portals S1 and S2. One of the screws is passed with a washer and is tightened first to achieve graft reduction and compression. D, Percutaneous tightening of the screws with 2 screwdrivers (SD) through portals S1 and S2 is shown. E, Final coracoid graft (Co) approximation with the glenoid (GL), and screw positions (S1, S2), are shown. GL indicates glenoid; H, humeral head; V1 and V2, viewing portals.
RESULTS Between 2013 and 2014, the ALCS procedure was performed and analyzed in 14 patients who presented with recurrent anterior instability with significant bone loss. The capsule could be dissected, preserved, and reattached in 12 of the 14
patients (86%). Two double-loaded anchors were required in 8 patients (67%), and in 4 patients (33%), only 1 double-loaded anchor was sufficient. Radiographic union was seen in all 14 patients. All patients returned to their preoperative functional and sporting levels, and none had recurrence of instability.
FIGURE 8. Radiologic images of final graft position. The computed tomography scan (right top and bottom) shows accurate positioning and congruence of the graft with the glenoid surface. Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved.
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FIGURE 9. Passage of suture anchor (AN) into the anterior glenoid rim (9A), and reattachment of the capsule to the anterior glenoid rim (9B) is shown. AN indicates anchor; Co, coracoid; Cp, capsule; GL, glenoid; H, humeral head; K, knot pusher.
Complications The ALCS procedure may result in potential complications at each step of the procedure. Careful dissection and thorough knowledge of arthroscopic anatomy is required to avoid these complications. (a) Axillary nerve injury: The axillary nerve is at risk for injury during capsular detachment, and during subscapularis split. Injury to this nerve may be avoided by careful bursal clearance anterior to the subscapularis down to the level of the leash of anterior circumflex vessels. Further inferior dissection helps identify the axillary nerve, and the split is then performed well above the neurovascular structures. During capsular dissection, the capsule should be detached as close to the glenoid rim as possible. The
anterior surface of the capsule should be separated by blunt dissection only. (b) Musculocutaneous nerve and BP injury: The musculocutaneous nerve and the BP are at risk for injury during dissection medial to the coracoid process. To avoid injury, PM tenotomy should be performed as close to the medial coracoid surface as possible, and the medial release of CT should not exceed 4 cm below the coracoid tip. Identification of the nerve may be used as an additional safeguard. (c) Subscapularis injury: This may occur during capsular separation and anterior subscapularis clearance, and subscapularis split. The injury may be prevented by avoiding direct contact of RF probe and shaver blade with the muscle. Subscapularis split should be performed in a
TABLE 1. Rehabilitation Protocol for the ALCS Procedure
Phase
Range of Motion
Phase 1 (0-4 wk) Week 1 Week 2 0-30 degrees, passive
Nil
Immobilization Method Sling only, arm in internal rotation Sling only, arm in internal rotation
Week 3 (1) Passive abduction and flexion (scapular plane) Sling only, arm in internal restricted to 60 degrees rotation (2) Passive external and internal rotations (arm adducted) to 30 degrees Week 4 (1) Passive abduction and flexion Sling only, arm in internal (scapular plane) to 90 degrees rotation (2) Passive external and internal rotations (arm adducted) to 45 degrees (3) Transition to active-assisted exercises within the same range of motion Phase 2 (1) Active abduction and flexion Nil (4-8 wk) (scapular plane) to 90 degrees, and progression to full active overhead range (2) Active rotational range of motion with arm in adduction is increased to 60 degrees of external (3) Active rotational range with the arm in 90 degrees of abduction is initiated and progresses to full internal and external rotation Phase 3 Muscle strengthening exercises Nil (9 wk to 6 mo)
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Exercise Nil (1) Pendulum exercises for the shoulder (2) Elbow, wrist, and hand exercises (1) Passive supervised sessions (2) Elbow, wrist, and hand exercises (1) Passive and active assisted exercises (2) Elbow, wrist, and hand exercises
1. Active range exercises 2. Elbow, wrist, and hand exercises
(1) Theraband exercise (2) Weights (3) Scapular stabilizing exercises
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linear manner, along the direction of the fibers. The split should not extend >1 cm medial to the glenoid rim, to avoid damage to the subscapular nerves. Lateral extension of the split may also endanger the capsule and long head of the biceps tendon. (d) Graft breakage: This can occur during coracoid osteotomy and coracoid fixation. It may be prevented by performing the osteotomy 3 to 5 mm away from the screw hole, and by avoiding the use of a burr for osteotomy. The burr may be used simply to decorticate the osteotomy area, and osteotomes should be used to complete the osteotomy. (e) Graft malpositioning: Graft fixation is a “freehand” technique in the ALCS procedure, and malrotation and/or cephalization may occur. Coracoid malrotation may be prevented by use of Kocher grasping forceps that may be placed through the same portal as the screw. Once the proximal screw is tightened, the graft does not rotate and the distal screw may be passed without any problem. Graft cephalization is prevented by placing the proximal glenoid hole below the 2 o’clock position.
Rehabilitation Rehabilitation protocol after the ALCS procedure is similar to the protocol for mini-open dual-window subscapularis sparing approach described earlier.8 The shoulder is immobilized in a sling for 4 weeks. Active range of motion is begun after 4 weeks, and progressed to full active range within 3 months. Return to full sporting activity is permitted by 6 to 9 months. The overall rehabilitation protocol and the timeline are summarized in Table 1.
REFERENCES 1. Latarjet M. A propos du traitement des luxations re0 cidivante de l’epaule. Lyon Chir. 1954;49:994–1003. 2. Young AA, Maia R, Berhouet J, et al. Open Latarjet procedure for management of bone loss in anterior instability of the glenohumeral joint. J Shoulder Elbow Surg. 2011;20(suppl):S61–S69. 3. Lafosse L, Boyle S. Arthroscopic Latarjet procedure. J Shoulder Elbow Surg. 2010;19(suppl):2–12. 4. Ranne JO, Kainonen TU, Lehtinen JT, et al. Modified arthroscopic latarjet procedure with coracoid exteriorization for treatment of anterior glenohumeral instability. Arthrosc Tech. 2013;2:e361–e365.
Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved.
Arthroscopic Latarjet and Capsular Shift (ALCS) Procedure
5. Burkhart SS, De Beer JF. Traumatic glenohumeral bone defects and their relationship to failure of arthroscopic Bankart repairs: significance of the inverted-pear glenoid and the humeral engaging Hill-Sachs lesion. Arthroscopy. 2000;16:677–694. 6. Hovelius L, Sandstro¨m B, Olofsson A, et al. The effect of capsular repair, bone block healing, and position on the results of the BristowLatarjet procedure (study III): long-term follow-up in 319 shoulders. J Shoulder Elbow Surg. 2012;21:647–660. 7. Bhatia DN, DasGupta B. Surgical treatment of significant glenoid bone defects and associated humeral avulsions of glenohumeral ligament (HAGL) lesions in anterior shoulder instability. Knee Surg Sports Traumatol Arthrosc. 2013;21:1603–1609. 8. Bhatia DN. Dual-window subscapularis-sparing approach: a new surgical technique for combined reconstruction of a glenoid bone defect or bankart lesion associated with a HAGL lesion in anterior shoulder instability. Tech Hand Up Extrem Surg. 2012;16: 30–36. 9. Schulze-Borges J, Agneskirchner JD, Bobrowitsch E, et al. Biomechanical comparison of open and arthroscopic Latarjet procedures. Arthroscopy. 2013;29:630–637. 10. Wellmann M, de Ferrari H, Smith T, et al. Biomechanical investigation of the stabilization principle of the Latarjet procedure. Arch Orthop Trauma Surg. 2011;132:377–386. 11. Yamamoto N, Muraki T, Sperling JW, et al. Stabilizing mechanism in bone-grafting of a large glenoid defect. J Bone Joint Surg Am. 2010;92:2059–2066. 12. Balg F, Boileau P. The instability severity index score. A simple pre-operative score to select patients for arthroscopic or open shoulder stabilisation. J Bone Joint Surg Br. 2007;89:1470–1477. 13. Wolf EM, Arianjam A. Hill-Sachs remplissage, an arthroscopic solution for the engaging Hill-Sachs lesion: 2- to 10-year follow-up and incidence of recurrence. J Shoulder Elbow Surg. 2014;23: 814–820. 14. Bhatia DN, de Beer JF, du Toit DF. Coracoid process anatomy: implications in radiographic imaging and surgery. Clin Anat. 2007;20:774–784. 15. Yung SW, Lazarus MD, Harryman DT II. Practical guidelines to safe surgery about the subscapularis. J Shoulder Elbow Surg. 1996;5:467–470. 16. Bhatia DN. The “double-barrel” knot. a new sliding knot for arthroscopic soft tissue fixation using single-pulley and double-pulley techniques. Tech Hand Up Extrem Surg. 2013;17: 128–133.
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Arthroscopic Latarjet and Capsular Shift (ALCS) Procedure: A New “Freehand” Technique for Anterior Shoulder Instability Associated With Significant Bone Defects Deepak N. Bhatia, MS(Orth), DNB(Orth)
Abstract: Anterior shoulder instability associated with significant bone loss has been described as “bony-instability,” and this condition is usually treated with an anterior glenoid bone grafting procedure (Latarjet procedure). The Latarjet procedure involves transfer of the horizontal limb of the coracoid process along with the conjoint tendon to the anterior glenoid rim, and is traditionally performed as an open surgical procedure. Recently, an arthroscopic technique for the Latarjet procedure has been described; the technique necessitates the use of specialized instrumentation and involves excision of the entire anterior capsule to facilitate coracoid fixation. We describe a new “freehand” arthroscopic technique for the Latarjet procedure, and, in addition, a simultaneous capsular shift to further optimize mid and end range stability. This technique eliminates the use of additional instrumentation and can be done using routine arthroscopic instruments. Preliminary experience with this technique suggests that the arthroscopic Latarjet and capsular shift is a technically demanding procedure. Glenohumeral capsule can be preserved, and this should be attempted wherever possible to optimize stability. Additional specialized instrumentation would probably reduce surgical time; however, the procedure can be performed with routine instruments. Key Words: Latarjet procedure, capsular shift, shoulder arthroscopy, shoulder instability (Tech Hand Surg 2015;19: 11–17)
HISTORICAL PERSPECTIVE The Latarjet procedure (open and mini-open) is a well recognized and accepted technique for surgical treatment of anterior instability associated with significant bone defects. The procedure involves transfer of the coracoid process to the anterior glenoid for reconstruction of the glenoid bone loss. The procedure was first described by Latarjet in 1955, and several modifications have evolved thereafter.1,2 Recently, Lafosse and Boyle have described an arthroscopic technique for the Latarjet procedure for safe and reproducible coracoid fixation to the deficient anterior glenoid. The authors reported excellent results in a large series of patients using this technique.3 The procedure involves excision of the entire anterior glenohumeral capsule to permit adequate visualization and to facilitate graft passage without obstruction. The procedure is performed with special instrumentation (Mitek) that simplifies the procedure and makes it reproducible and safe. A modification of the arthroscopic Latarjet procedure has been described, and this technique also involves excision of the anterior capsule.4 From the Department of Orthopaedic Surgery, Seth GS Medical College, and King Edward VII Memorial Hospital, Mumbai, India. Conflicts of Interest and Source of Funding: The authors report no conflicts of interest and no source of funding. Address correspondence and reprint requests to Deepak N. Bhatia, MS(Orth), DNB(Orth), Department of Orthopaedic Surgery, Seth GS Medical College, and King Edward VII Memorial Hospital, Parel, Mumbai 400012, India. E-mail: [email protected]. Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved.
Techniques in Hand & Upper Extremity Surgery
The role of preservation of the anterior capsule has been analyzed in biomechanical and clinical studies, and closure of the capsule has recently been described as an important component of the Latarjet procedure. Young et al2 described the use of the coracoacromial (CA) ligament to reconstruct the anterior capsule. Burkhart and DeBeer5 described the congruent-arc modification with an added capsular shift for greater stability. Hovelius et al6 showed a significantly better outcome in Latarjet procedure with capsular repair. Bhatia and DasGupta found an 11% incidence of humeral avulsion glenohumeral ligament lesions (HAGL) associated with significant glenoid defects, and described excellent results with a new dual-window subscapularis-sparing approach for combined Latarjet procedure, capsular shift, and HAGL lesion repair.7,8 Biomechanical studies have further quantified the role of capsular closure in this procedure. Schulze-Borges and colleagues compared open and arthroscopic Latarjet procedure, and found a superior stabilization effect of the open Latarjet procedure in a pure abduction position of the arm, as compared with the arthroscopic Latarjet. They ascribed this difference to anterior capsular repair, which was performed in the open technique, and omitted during the arthroscopic procedure.9 Wellmann et al10 investigated the biomechanical status of different components of the Latarjet procedure, and concluded that anterior capsule reconstruction represented a significant contribution to the stabilizing effect of the Latarjet procedure. Yamamoto et al11 found that anterior capsular closure contributed to approximately 25% of the end range stability. We describe a new arthroscopic Latarjet technique that involves coracoid transfer and capsular shift. The entire anterior capsule is detached initially, and is reattached to the glenoid rim after coracoid fixation, thereby exteriorizing the bone graft. The procedure is performed with routine arthroscopic instruments, and may, therefore, be used even when special instrumentation is unavailable.
INDICATIONS The arthroscopic Latarjet and capsular shift (ALCS) procedure is performed in anterior glenohumeral instability associated with significant bony defects (> 20% to 25% glenoid loss).7 Balg and Boileau12 have described an Instability Severity Index Score, and a score of 6 or greater necessitates a bone grafting procedure like the ALCS. Larger “engaging” Hill-Sachs lesions without glenoid loss are relative indications, although these lesions may also be treated with a “remplissage” procedure.13 In some patients, poor capsular tissue may preclude an effective soft tissue repair, and an ALCS procedure may be indicated.
CONTRAINDICATIONS The ALCS procedure is relatively contraindicated in patients with no bone defects, and strong capsular tissue. The only exception to this is contact athletes. The procedure should be performed with caution in patients with poor bone mineral
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colleagues. The coracoid and screw portals are created with a 5 mm stab incision, and the drilling, osteotomy, and screw passage is percutaneous without the use of a large diameter cannula. A diagnostic arthroscopy is performed by the standard posterior portal; the glenoid and humeral bone defects are visualized and quantified. Any associated soft tissue lesions (superior labral tears, HAGL lesions) are noted and may be treated at this stage.7 Thereafter, the ALCS procedure can be simplified into the following 7 steps:
Step 1: Capsulotomy and Capsular Preservation FIGURE 1. Arthroscopic shoulder portals are shown. V1 and V2 are anterolateral viewing portals. C1 and C2 are percutaneous coracoid drilling portals. S1 and S2 are percutaneous coracoid fixation portals.
density and patients with relatively smaller coracoid processes; these are prone to graft breakage and suboptimal screw purchase, and may result in intraoperative complications.
SURGICAL TECHNIQUE Positioning and Portals The patient is placed in a high beach-chair position (60 to 80 degrees), and the shoulder is draped with adequate anteromedial clearance; this position facilitates medial portal placement for graft fixation. A standard posterior viewing portal (1 to 2 cm medial and inferior to the posterolateral acromial angle) is placed in the standard “soft spot.” A standard anterior portal (A) is placed in the rotator interval. Additional portals include V1 and V2 (viewing portals), C1 and C2 (portals for coracoid drilling and osteotomy), S1 and S2 (portals for screw fixation) (Fig. 1). These portals have been modified from the original arthroscopic Latarjet procedure described by Lafosse and
This is the most important difference between the ALCS and other modifications of the arthroscopic Latarjet procedure. The capsulotomy is initiated at the rotator interval, and a transverse excision of rotator interval capsule is performed. The capsulolabral complex is then dissected from the anterior glenoid rim using a radiofrequency (RF) probe tip, or arthroscopic scissors, by the standard anterior portal (A). The capsulotomy is extended down to the 6 o’clock position on the glenoid, and care is taken to limit dissection to the bonelabrum junction. Next, the capsule is separated from the subscapularis muscle using blunt dissection. This maneuver preserves both capsular and subscapularis fibers, and does not compromise vascularity and innervation. Adequate mobility of the capsule is confirmed by grasping the capsule and checking medial approximation to glenoid rim (Figs. 2A–E).
Step 2: Coracoid Exposure Coracoid dissection is performed with a shaver and RF probe by the standard anterior portal (A) and V1. The coracoacromial ligament (CA) and conjoint tendon (CT) are identified the CA attachment to the coracoid process is separated, and the tendinous fibers of the CT, covering the coracoid tip, are preserved. Next, the clavipectoral fascia (CL) lateral to the CT is cut for approximately 4 to 5 cm inferior to the coracoid tip.
FIGURE 2. Surgical steps for capsulotomy and capsular preservation are shown. A, Anterior significant glenoid bone loss can be visualized. B, The capsule is shown after separation from the anterior glenoid rim. The underlying subscapularis fibers can be visualized. C, The capsule is separated from the underlying subscapularis muscle. D, The capsule is retracted laterally and the subscapularis fibers are visible. E, The capsule is grasped and approximated to the anterior glenoid rim to ascertain mobility. Cp indicates capsule; G, glenoid, H, humeral head; SSc, subscapularis; Gr, grasper.
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Arthroscopic Latarjet and Capsular Shift (ALCS) Procedure
FIGURE 3. A, Arthroscopic dissection of the coracoid attachments is shown. The coracoacromial ligament (CA) is visualized as a glistening white structure attaching to the superior surface of the coracoid (Co). The conjoint tendon (CT) attaches to the coracoid tip. The clavipectoral fascia (CL) extends laterally from the tendinous edge of the conjoint tendon. B, The pectoralis minor tendon (Pm) is separated from the medial coracoid surface (Co). C, Medial dissection under the pectoralis minor muscle (Pm) reveals a constant fat pad (FP), and the brachial plexus (BP) underneath. Co indicates coracoid process; RF, radiofrequency probe; ssc, subscapularis tendon.
The arthroscope is now shifted to the V1 portal, and a V2 portal is created adjacent to the coracoid tip. The RF probe is placed in the V2 portal, and the pectoralis minor (PM) is exposed and dissected off the medial border of the superior coracoid pillar. A constant fat pad is identified deep to the PM and further medial dissection is not necessary. The brachial plexus (BP) is medial to this fat pad, and blunt dissection in this region will usually identify the musculocutaneous nerve. The CT is released from the medial fascia for 2 to 4 cm below the coracoid tip. The superior surface of the coracoid process is cleared up to the trapezoid ligament, and a constant ridge, just anterior to this ligament, serves as a guide to the trapezoid ligament and subsequent osteotomy (Figs. 3A–C).14
Step 3: Coracoid Drilling Coracoid drilling is performed by percutaneous portals C1 and C2. These are located using needles, and a 3.5 mm guide cannula is placed through the percutaneous portals. Wires for cannulated drill system are passed through the superior coracoid surface, and exit through the undersurface under vision. A 3.2 mm cannulated drill bit is passed over the wires and drill holes are completed. This method of “freehand”
placement of drill holes allows for precise placement of 2 holes even in smaller coracoids, as compared with standard drill guides, which only allow a fixed distance between the screws. The undersurface of the coracoid is prepared at this stage; arthroscopic burrs and a rasp (PoweRasp, Arthrex) are used to lightly decorticate the coracoid undersurface for later fixation (Figs. 4A–C).
Step 4: Coracoid Osteotomy Two 5 mm narrow osteotomes are placed on the superior and inferior surfaces of the superior coracoid pillar. The superior osteotome (OS1) is placed percutaneously through the C1 or C2 portals, and the inferior osteotome (OS2) is placed through a 6 mm cannula in portal V2. This approach provides the correct angles for the osteotomy, and preserves bone in smaller coracoids. A constant ridge between the junctional surface area and superior coracoid pillar serves as a guide and the osteotomy must be limited to this level to prevent inadvertent damage to the coracoclavicular ligaments.14 The osteotomy approach also prevents extension of the osteotomy into the drill holes, which may happen if a burr is used for osteotomy (Fig. 5).
FIGURE 4. Percutaneous coracoid drilling is shown. A, Guide wires (W1 AND W2) are placed through percutaneous cannulas by coracoid portals. B, The exact points for drilling the guide wires is ascertained using spinal needles (C1, C2) after coracoid (Co) exposure. C, The coracoid process (Co) is drilled using a cannulated drill-bit (DR) over the guide wire (G). Inferior migration of the guide wire is prevented by placing a shaver blade (B) under the guide wire. SH indicates arthroscope sheath; CT, conjoint tendon; V1 and V2, anterolateral viewing portals; S1 and S2 are percutaneous coracoid fixation portals. Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved.
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performed with caution to avoid damaging the preserved anterior capsule, and the long biceps tendon (Figs. 6A, B).
Step 6: Coracoid Fixation
FIGURE 5. Coracoid osteotomy is performed using 2 curved osteotomes (OS1 and OS2) placed through C1/C2 portal and V2 portal. V1 and V2 are anterolateral viewing portals. C1 and C2 are percutaneous coracoid drilling portals. S1 and S2 are percutaneous coracoid fixation portals.
Step 5: Subscapularis Split The anterior surface of the subscapularis is cleared down to the leash of the anterior circumflex vessels. A Wissenger rod is passed into the glenohumeral joint through the posterior portal, and through the subscapularis; the passage is performed before the coracoid osteotomy and is lateral to the CT, at the midpoint between the upper subscapularis border and leash of vessels. The subscapularis is split using the RF probe, and the Wissenger rod is used to lever the subscapularis superiorly, thereby facilitating the split. The split should be restricted medially up to 10 mm from the anterior glenoid rim to protect the subscapularis nerves.15 Laterally, the split should be
An outside-in technique is used to create 2 medial portals S1 and S2, these portals are guided by the posterior Wissenger rod that was passed through the subscapularis, and should have a trajectory as parallel as possible to the glenoid articular surface. A guide wire is passed through the superior cannula and is directed approximately 5 mm medial to the glenoid articular surface on the anterior glenoid neck just below the 2 o’clock position. A long 3.2 mm cannulated drill bit is used to drill this hole through both cortices; the wire and drill bit are withdrawn, and a depth gauge is used to measure the length of the hole. A wire is now reinserted through the cannula into the upper coracoid hole, and directed into the glenoid drill hole. The cannula is withdrawn, and a 4 mm cannulated cancellous screw with a washer is passed percutaneously into the coracoid graft. The screw is advanced over the wire into the glenoid; further tightening leads to an indirect reduction of the coracoid onto the glenoid, and the subscapularis fibers are retracted superiorly just before intra-articular entry of the graft. Thereafter, a second wire is placed through portal S1 or S2 into the coracoid and glenoid, and the steps are repeated to place a second screw for graft fixation. Final tightening is performed simultaneously with 2 screwdrivers to achieve graft compression (Figs. 7A–E and 8).
Step 7: Capsular Shift and Graft Exteriorization Capsular shift of the preserved anterior capsule is performed by viewing through the standard posterior portal, and working through the V1 and A portals (Fig. 9). The capsule is grasped and approximated to the glenoid to determine the integrity and tissue tension. Usually, the anterior band of the inferior glenohumeral ligament is well preserved, and is used to anchor the capsular tissue to the glenoid. One or 2 double-loaded anchors are passed through the V1 portal into the 4 and 2 o’clock positions on the anterior glenoid rim. An antegrade or retrograde suture passing device is used to pass sutures through the capsule in a mattress manner. Thereafter, sliding knots (double-barrel knot) are tied in 20 to 30 degrees of external rotation to approximate the capsule to the glenoid.16 The capsular closure completely covers the coracoid graft and exteriorizes it.
FIGURE 6. Steps for splitting the subscapularis muscle are shown. A, A Wissenger rod (G) passed through the posterior portal and through the subscapularis (SSC) lateral to the conjoint tendon. B, The subscapularis is split from medial to lateral at the level marked by the rod. H indicates humeral head; GL, glenoid; RF radiofrequency probe.
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Arthroscopic Latarjet and Capsular Shift (ALCS) Procedure
FIGURE 7. A guide wire G is placed through one of the coracoid (Co) holes (7A) and passed through a predrilled glenoid hole (7B). C, Percutaneous cannulated screw (Cn) passage is shown over guide wires G1 and G2 through portals S1 and S2. One of the screws is passed with a washer and is tightened first to achieve graft reduction and compression. D, Percutaneous tightening of the screws with 2 screwdrivers (SD) through portals S1 and S2 is shown. E, Final coracoid graft (Co) approximation with the glenoid (GL), and screw positions (S1, S2), are shown. GL indicates glenoid; H, humeral head; V1 and V2, viewing portals.
RESULTS Between 2013 and 2014, the ALCS procedure was performed and analyzed in 14 patients who presented with recurrent anterior instability with significant bone loss. The capsule could be dissected, preserved, and reattached in 12 of the 14
patients (86%). Two double-loaded anchors were required in 8 patients (67%), and in 4 patients (33%), only 1 double-loaded anchor was sufficient. Radiographic union was seen in all 14 patients. All patients returned to their preoperative functional and sporting levels, and none had recurrence of instability.
FIGURE 8. Radiologic images of final graft position. The computed tomography scan (right top and bottom) shows accurate positioning and congruence of the graft with the glenoid surface. Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved.
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FIGURE 9. Passage of suture anchor (AN) into the anterior glenoid rim (9A), and reattachment of the capsule to the anterior glenoid rim (9B) is shown. AN indicates anchor; Co, coracoid; Cp, capsule; GL, glenoid; H, humeral head; K, knot pusher.
Complications The ALCS procedure may result in potential complications at each step of the procedure. Careful dissection and thorough knowledge of arthroscopic anatomy is required to avoid these complications. (a) Axillary nerve injury: The axillary nerve is at risk for injury during capsular detachment, and during subscapularis split. Injury to this nerve may be avoided by careful bursal clearance anterior to the subscapularis down to the level of the leash of anterior circumflex vessels. Further inferior dissection helps identify the axillary nerve, and the split is then performed well above the neurovascular structures. During capsular dissection, the capsule should be detached as close to the glenoid rim as possible. The
anterior surface of the capsule should be separated by blunt dissection only. (b) Musculocutaneous nerve and BP injury: The musculocutaneous nerve and the BP are at risk for injury during dissection medial to the coracoid process. To avoid injury, PM tenotomy should be performed as close to the medial coracoid surface as possible, and the medial release of CT should not exceed 4 cm below the coracoid tip. Identification of the nerve may be used as an additional safeguard. (c) Subscapularis injury: This may occur during capsular separation and anterior subscapularis clearance, and subscapularis split. The injury may be prevented by avoiding direct contact of RF probe and shaver blade with the muscle. Subscapularis split should be performed in a
TABLE 1. Rehabilitation Protocol for the ALCS Procedure
Phase
Range of Motion
Phase 1 (0-4 wk) Week 1 Week 2 0-30 degrees, passive
Nil
Immobilization Method Sling only, arm in internal rotation Sling only, arm in internal rotation
Week 3 (1) Passive abduction and flexion (scapular plane) Sling only, arm in internal restricted to 60 degrees rotation (2) Passive external and internal rotations (arm adducted) to 30 degrees Week 4 (1) Passive abduction and flexion Sling only, arm in internal (scapular plane) to 90 degrees rotation (2) Passive external and internal rotations (arm adducted) to 45 degrees (3) Transition to active-assisted exercises within the same range of motion Phase 2 (1) Active abduction and flexion Nil (4-8 wk) (scapular plane) to 90 degrees, and progression to full active overhead range (2) Active rotational range of motion with arm in adduction is increased to 60 degrees of external (3) Active rotational range with the arm in 90 degrees of abduction is initiated and progresses to full internal and external rotation Phase 3 Muscle strengthening exercises Nil (9 wk to 6 mo)
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Exercise Nil (1) Pendulum exercises for the shoulder (2) Elbow, wrist, and hand exercises (1) Passive supervised sessions (2) Elbow, wrist, and hand exercises (1) Passive and active assisted exercises (2) Elbow, wrist, and hand exercises
1. Active range exercises 2. Elbow, wrist, and hand exercises
(1) Theraband exercise (2) Weights (3) Scapular stabilizing exercises
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Techniques in Hand & Upper Extremity Surgery
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linear manner, along the direction of the fibers. The split should not extend >1 cm medial to the glenoid rim, to avoid damage to the subscapular nerves. Lateral extension of the split may also endanger the capsule and long head of the biceps tendon. (d) Graft breakage: This can occur during coracoid osteotomy and coracoid fixation. It may be prevented by performing the osteotomy 3 to 5 mm away from the screw hole, and by avoiding the use of a burr for osteotomy. The burr may be used simply to decorticate the osteotomy area, and osteotomes should be used to complete the osteotomy. (e) Graft malpositioning: Graft fixation is a “freehand” technique in the ALCS procedure, and malrotation and/or cephalization may occur. Coracoid malrotation may be prevented by use of Kocher grasping forceps that may be placed through the same portal as the screw. Once the proximal screw is tightened, the graft does not rotate and the distal screw may be passed without any problem. Graft cephalization is prevented by placing the proximal glenoid hole below the 2 o’clock position.
Rehabilitation Rehabilitation protocol after the ALCS procedure is similar to the protocol for mini-open dual-window subscapularis sparing approach described earlier.8 The shoulder is immobilized in a sling for 4 weeks. Active range of motion is begun after 4 weeks, and progressed to full active range within 3 months. Return to full sporting activity is permitted by 6 to 9 months. The overall rehabilitation protocol and the timeline are summarized in Table 1.
REFERENCES 1. Latarjet M. A propos du traitement des luxations re0 cidivante de l’epaule. Lyon Chir. 1954;49:994–1003. 2. Young AA, Maia R, Berhouet J, et al. Open Latarjet procedure for management of bone loss in anterior instability of the glenohumeral joint. J Shoulder Elbow Surg. 2011;20(suppl):S61–S69. 3. Lafosse L, Boyle S. Arthroscopic Latarjet procedure. J Shoulder Elbow Surg. 2010;19(suppl):2–12. 4. Ranne JO, Kainonen TU, Lehtinen JT, et al. Modified arthroscopic latarjet procedure with coracoid exteriorization for treatment of anterior glenohumeral instability. Arthrosc Tech. 2013;2:e361–e365.
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Arthroscopic Latarjet and Capsular Shift (ALCS) Procedure
5. Burkhart SS, De Beer JF. Traumatic glenohumeral bone defects and their relationship to failure of arthroscopic Bankart repairs: significance of the inverted-pear glenoid and the humeral engaging Hill-Sachs lesion. Arthroscopy. 2000;16:677–694. 6. Hovelius L, Sandstro¨m B, Olofsson A, et al. The effect of capsular repair, bone block healing, and position on the results of the BristowLatarjet procedure (study III): long-term follow-up in 319 shoulders. J Shoulder Elbow Surg. 2012;21:647–660. 7. Bhatia DN, DasGupta B. Surgical treatment of significant glenoid bone defects and associated humeral avulsions of glenohumeral ligament (HAGL) lesions in anterior shoulder instability. Knee Surg Sports Traumatol Arthrosc. 2013;21:1603–1609. 8. Bhatia DN. Dual-window subscapularis-sparing approach: a new surgical technique for combined reconstruction of a glenoid bone defect or bankart lesion associated with a HAGL lesion in anterior shoulder instability. Tech Hand Up Extrem Surg. 2012;16: 30–36. 9. Schulze-Borges J, Agneskirchner JD, Bobrowitsch E, et al. Biomechanical comparison of open and arthroscopic Latarjet procedures. Arthroscopy. 2013;29:630–637. 10. Wellmann M, de Ferrari H, Smith T, et al. Biomechanical investigation of the stabilization principle of the Latarjet procedure. Arch Orthop Trauma Surg. 2011;132:377–386. 11. Yamamoto N, Muraki T, Sperling JW, et al. Stabilizing mechanism in bone-grafting of a large glenoid defect. J Bone Joint Surg Am. 2010;92:2059–2066. 12. Balg F, Boileau P. The instability severity index score. A simple pre-operative score to select patients for arthroscopic or open shoulder stabilisation. J Bone Joint Surg Br. 2007;89:1470–1477. 13. Wolf EM, Arianjam A. Hill-Sachs remplissage, an arthroscopic solution for the engaging Hill-Sachs lesion: 2- to 10-year follow-up and incidence of recurrence. J Shoulder Elbow Surg. 2014;23: 814–820. 14. Bhatia DN, de Beer JF, du Toit DF. Coracoid process anatomy: implications in radiographic imaging and surgery. Clin Anat. 2007;20:774–784. 15. Yung SW, Lazarus MD, Harryman DT II. Practical guidelines to safe surgery about the subscapularis. J Shoulder Elbow Surg. 1996;5:467–470. 16. Bhatia DN. The “double-barrel” knot. a new sliding knot for arthroscopic soft tissue fixation using single-pulley and double-pulley techniques. Tech Hand Up Extrem Surg. 2013;17: 128–133.
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