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    Arthroscopic Latarjet Procedure for Shoulder Instability

    A 24-year-old hockey player had undergone a Bankart repair due to recurrent instability of his left shoulder. After a fall, he’s now dislocating at rest, with significant subjective instability of the shoulder. What can be done to stabilize the joint?

    Authors

    Eric M. Black, MD; George S. Athwal, MD, FRCSC; and Charles Getz, MD

    Disclosures

    The authors have no disclosures relevant to this article.

    Case Presentation

    A 24-year-old male who plays ice hockey presented with recurrent left shoulder instability. He has a history of multiple dislocations to his left shoulder. Six years prior, he had undergone an arthroscopic Bankart procedure with metallic anchors; the procedure was performed at another hospital.

    The patient had been doing well until he fell 3 years after the repair. Since the fall, he has sustained multiple dislocation events, each time with less force. Now he is dislocating at rest, with significant subjective instability of the shoulder. Multiple dislocations have required reduction in the emergency department.

    Physical Examination

    • Apprehension with elevation (>150°), external rotation at neutral (>40°), abduction/external rotation (>40°)
    • +2 anterior translation, negative posterior translation, negative sulcus sign
    • Intact rotator cuff strength testing
    • Slight crepitance at extremes of motion
    • Neurovascularly intact (including axillary nerve)

    Differential Diagnosis

    • Labral tear
    • Labral tear + large engaging Hill Sachs
    • Labral tear + glenoid bone loss
    • Labral tear + large engaging Hill Sachs + glenoid bone loss
    • Humeral avulsion of the glenohumeral ligament (HAGL)

    Imaging

    • X-rays and CT scan were ordered to assess bone loss
    • 15% bone loss on glenoid, minimal arthritis (Figure 1)
    • Severe blunting of the anterior glenoid rim with a lack of labral tissue (Figure 2; left is anterior)

    Figure 1. Preoperative axial MRI showing approximately 15% bone loss and anterior labral deficiency.

    Figure 2. Blunting of anterior glenoid rim, indicative of approximately 15% bone loss.

    Diagnosis

    The patient is a 24-year-old male with recurrent instability of the left shoulder and a history of a prior Bankart repair. He has 15% bone loss on radiographic examination. There is no significant engaging Hill Sachs lesion.

    Treatment

    The authors recommended an arthroscopic Latarjet (coracoid bone block) procedure. Advantages of this procedure include the following:

    • Ability to concomitantly address additional pathology in joint, such as a rotator cuff tear or SLAP tear
    • Graft placement under direct vision to graft/glenoid interface, which decreases the risk of graft overhang/impingement
    • Less invasive, lesser risk of postoperative adhesions
    • Improved cosmesis

    There are disadvantages as well:

    • Technically challenging
    • Steep learning curve
    • Performing subscapularis split and passing graft can damage subscapularis if care is not taken
    • Anteromedial portal risks injuring brachial plexus
    • Prolonged surgical time can lead to increased risk of swelling

    The patient agreed to the procedure. The authors used a Depuy Mitek Bristow Latarjet Instability Shoulder System (Depuy Mitek, Raynham, Massachusetts). Advantages of this system include:

    • The coracoid “top hats” are placed into the superior aspect of coracoid prior to osteotomy, allowing the aiming gun to adequately fix to the coracoid for maximal control.
    • The cannulated nature of the system allows for improved accuracy of graft placement and provisional fixation during the procedure.

    There are a few disadvantages as well:

    • The screws are cannulated and inherently weaker than solid screws.
    • The ratio of thread diameter to core diameter is smaller than with traditional fixation methods.
    • The coracoid “top hats” can be dislodged into the shoulder during the procedure.

    Surgical Technique

    Setup

    • Standard beach chair position, head tilted away
    • Wide sterile prep: All of ipsilateral pectoralis and scapula prepped and draped into sterile field to allow for transpectoral portal and guide pin retraction, respectively
    • Pump pressure at 30 to 35 mmHg to minimize swelling
    • Towel clips can hold portals closed when not in use to minimize leakage

    Portal placement (Figure 3)

    • Posterior: Bias medially, in line and parallel with glenohumeral joint
    • Anterior: Through middle of rotator interval
    • Three subscapularis portals: Laterally based, superior to inferior; allows visual and working access to anterior compartment of shoulder
    • Superior coracoid portal: Just anterior to clavicle above coracoid; facilitates top hat placement and coracoid osteotomy
    • Transpectoral portal/medial (M) portal: Large portal; facilitates graft placement

    Figure 3. Portal placement.

    Joint visualization/glenoid neck preparation, with the camera in the posterior portal

    • Assess joint, perform intraarticular work as needed
    • Open rotator interval widely with electrocautery, leaving lateral-most sleeve of tissue to stabilize biceps
    • Cauterize glenoid rim and neck and debride anterior joint capsule from subscapularis (Figure 4)
    • Gently burr anterior glenoid neck to bleeding bone to facilitate fusion of coracoid graft
    • Begin to expose subcoracoid recess, inferior border of coracoid, and lateral margin of coracoid (Figure 5)

    Figure 4. Debridement of anterior glenoid rim to expose bleeding bed.

    Figure 5. Circumferential coracoid exposure.

    Subscapularis split, with camera views from mid subscapularis portal

    • Further expose and debride glenoid neck free of soft tissue and capsule/labrum
    • Further expose and debride coracoid via anterior or inferior subscapularis portal
    • Expose axillary nerve to ensure location at inferior border of subscapularis (Figure 6)
    • Place long pointed switching stick from posterior portal through subscapularis, piercing subscapularis at midway point from superior to inferior, advance forward to tent skin; this will be location of M portal or transpectoral portal
    • Switching stick should pierce skin lateral to conjoint tendon
    • Split subscapularis medial and lateral to switching stick, using electrocautery to fully split tendon (laterally) and muscle (medially) (Figure 7)
    • Can utilize two switching sticks with opposing tension (upwards and downwards) to facilitate subscapularis split
    • Leave switching stick through subscapularis for later use

    Figure 6. Axillary nerve visualization below subscapularis.

    Figure 7. Subsapularis split.

    Coracoid preparation, with camera views from mid subscapularis portal

    • Fully debride all soft tissue away from coracoid superiorly and inferiorly
    • Release coracoacromial ligament laterally and pectoralis minor medially to the base
    • Can use switching stick through superior subscapularis portal to retract deltoid upwards
    • Free medial conjoint tendon from soft tissue, taking care not to injure musculocutaneous nerve
    • Establish superior coracoid portal
    • Introduce K-wire guide to top of coracoid and thread wires through coracoid; anterior hole should be approximately 1 cm away from coracoid tip (Figure 8)
    • Remove guide and drill holes into coracoid over K-wires
    • Place top hats into coracoid

    Figure 8. Coracoid preparation with guide pins.

    Coracoid osteotomy and mobilization, with camera views from mid subscapularis portal

    • Osteotomize coracoid using osteotome from superior coracoid portal (Figure 9)
    • Leave enough space from base of osteotomy to posterior top hat
    • Free up coracoid from base
    • Capture coracoid utilizing aiming gun/pistol grip guide through transpectoralis portal and thread fixation screws through top hats
    • Burr undersurface of coracoid to bleeding bone bed, contour undersurface to match glenoid neck surface; this can be done via superior or inferior subscapularis portal

    Figure 9. Coracoid osteotomy.

    Coracoid transfer through subscapularis, with camera views from mid subscapularis portal

    • Pistol grip guide transfers coracoid through subscapularis
    • Gentle internal rotation of arm facilitates subscapularis relaxation
    • Two long switching sticks can be placed posteriorly through joint, one with upward pressure the other with downward pressure to open subscapularis split
    • Top of coracoid should line up with 3 o’clock or 9 o’clock position on the glenoid (Figure 10)

    Figure 10. Undersurface of coracoid lining up with native glenoid neck.

    Coracoid fixation, with camera views from mid subscapularis portal

    • Drive two K-wires into glenoid to allow provisional fixation
    • Pierce K-wires through posterior and grab with clamps
    • Key point: K-wires should run parallel to glenoid face; should be no more than 20° off axis
    • Re-check coracoid placement to ensure there is no graft overhang
    • Remove top hat in alpha hole, drill utilizing 3.2-mm drill into glenoid, measure length off of drill utilizing direct visualization, place screw
    • Do the same in beta hole
    • Remove K-wires (Figure 11)

    Figure 11. Graft seated and secured just medial to glenoid face.

    Postoperative Course

    The patient tolerated the procedure well and was discharged home the same day as the procedure. He began pendulums immediately. His pain was minimal by 3 days postoperatively.

    Initial 2-week Postoperative Visit

    • Sutures removed
    • Gentle PROM (forward elevation to 140°, ER to 45°)
    • Graft confirmed to be in good position (Figure 12)

    Figure 12. Two-week postoperative X-rays. Note that the screw position is slightly more oblique than desirable, a consequence of the transpectoral portal being slightly lateral.

    4week Postoperative Visit

    • PROM to extension, internal rotation, cross-body adduction
    • External rotation, internal rotation, and forward elevation strengthening

    6-week Postoperative Visit

    • Rotator cuff strengthening, deltoid strengthening, scapular strengthening

    12-week Postoperative Visit

    • Return to sport

    6-month Postoperative Visit

    • Shoulder 90% of normal (Figure 13)
    • No instability
    • Returned to playing hockey

    Figure 13. Six-month postoperative X-rays showing complete graft incorporation.

    Author Information

    Eric M. Black, MD, and Charles Getz, MD, are from The Rothman Institute at Thomas Jefferson University Hospital, Philadelphia, Pennsylvania. George S. Athwal, MD, FRCSC, is from the Roth/McFarlane Hand & Upper Limb Centre at St. Joseph’s Health Care London, London, Ontario, Canada.

    Shoulder Reconstruction Section Editor, Rothman Institute Grand Rounds 

    Luke S. Austin, MD