Graft positioning is a critical aspect of the Latarjet procedure. Due to limited visualization of the anterior-inferior glenoid during an open Latarjet procedure, accurate positioning of the graft can be challenging. The consensus is that the graft should be positioned between 2 o’clock and 5 o’clock on the glenoid face of a right shoulder and between 10 o’clock and 7 o’clock on the glenoid face of a left shoulder, just medial to the chondral surface of the glenoid [2]. Placement of the graft too high on the glenoid can result in recurrent instability as it will not provide a bony restraint for the humeral head. Iatrogenic suprascapular nerve injury from a superior malpositioned screw can also occur [6–10]. Placement of the graft too low can make it difficult for the inferior screw to gain adequate purchase in the glenoid for stable fixation, possibly resulting in a fibrous nonunion [11]. Medial placement can result in recurrent instability through insufficient bone blocking, whereas lateral placement creates lateral overhang, a known risk factor for osteoarthritis (OA) [6, 12]. It has been suggested that visualization is improved with the arthroscopic Latarjet procedure, possibly decreasing the incidence of graft malpositioning. Commercially available guides can also aid in the proper positioning of the graft.

Transient and permanent neurovascular injuries to the musculocutaneous nerve, axillary nerve, radial nerve, brachial plexus, suprascapular nerve, and axillary artery have been reported in the literature [5]. While Shah et al. reported a 10% incidence of neurologic injury in their series of 48 shoulders [27], a 2013 systematic review reported an average 1.4% rate of neurovascular injuries across open and arthroscopic procedures, including 11 musculocutaneous, 6 axillary, and 4 trunk level brachial plexus nerve injuries [5].

A good understanding of the local shoulder anatomy is necessary to avoid these complications. In a cadaveric study, Lo et al. reported the anteromedial portion of the coracoid tip was closest to neurovascular structures [30]. The average distance from the anteromedial portion of the coracoid to the axillary nerve, the musculocutaneous nerve, the lateral cord, and the axillary artery was 30.3 ± 3.9 mm, 33.0 ± 6.2 mm, 28.5 ± 4.4 mm, and 36.8 ± 6.1 mm, respectively.

During the open Latarjet procedure, the high-risk stages for nerve injury are glenoid exposure and coracoid graft placement [13]. Recommendations to avoid iatrogenic injury include maintaining excellent visualization of the glenohumeral anatomy throughout the procedure and meticulous surgical technique around the coracoid, specifically the medial aspect. When removing structures from the coracoid, care must be taken to peel them directly from the bone to avoid inadvertent neurovascular injury. To avoid a traction injury to the musculocutaneous nerve, the coracoid must also be dissected free of soft tissue prior to its placement on the glenoid. Retraction around the glenoid should be kept to a minimum as a long operative time is a risk factor for axillary nerve injury [13].

If a nerve injury occurs, a computerized tomography (CT) scan of the shoulder should be obtained to evaluate screw placement and graft positioning [2]. If no abnormalities are noted, up to 3 months of observation are recommended to see whether the patient’s symptoms resolve spontaneously. If symptoms do not resolve, management options include nerve transfers and muscle flaps. While rare, if a vascular injury occurs, consultation with vascular surgery is recommended.

The coracoid process measures 21 ± 2 to 26 ± 2.9 mm in length and averages 9.3 ± 1.3 mm in thickness; therefore, extreme care must be taken during graft harvest and preparation to avoid fracture [14, 15]. A 2.5–3.0 cm graft is desirable to allow careful size for drill hole placement. The risk of graft fracture can be minimized through careful screw placement. While the optimal distance between screws is still debated, mean distances of 7.8–9 mm have produced good results [15, 16]. The use of commercially available guides, as stated previously, can aid in avoiding aberrant hole placement that can lead to graft fracture. Additionally, cancellous bone from drilling should be cleared before screw insertion, and excessive tightening should be avoided to prevent penetration or fracture of the graft. A washer or plate can be used to reinforce osteoporotic or otherwise poor-quality bone before drilling to minimize this complication.

If graft fracture occurs, the remaining bone quantity and quality as well as the direction of the fracture will influence management decisions [2]. For a longitudinal fracture or poor-quality bone, a modified Eden-Hybinette procedure can be utilized. In this procedure, a wedge-shaped, bicortical, or tricortical graft is harvested from the ipsilateral iliac crest and secured to the anterior glenoid rim [17]. For transverse fractures with adequate quality and quantity of bone, a bioabsorbable anchor can be used to supplement the hold of a single screw with good purchase. Alternatively, or in the case of a screw hole blowout, a buttress plate can be used to provide compression.

Loss of external rotation range of motion is common following the Latarjet procedure, with average losses of 13° reported in a recent systematic review [5]. This potential complication is not surprising, as the method by which the glenoid bone graft prevents engagement of a Hill-Sachs lesion is by extending the glenoid arc so that the shoulder cannot externally rotate far enough to engage the lesion over the front of the graft. Additionally, the tethering effect of the transferred conjoined tendon further restricts external rotation [18]. It has been reported that the arthroscopic Latarjet procedure results in larger losses in external rotation [5]. While a definitive reason for this discrepancy is unknown, the relatively longer length of time needed to perform the arthroscopic procedure has been hypothesized [5]. Furthermore, a subscapularis split has demonstrated less loss of external rotation than subscapularis tenotomy with subsequent reattachment [19]. Repairing the capsule to the coracoclavicular stump with the arm in external rotation may decrease the loss of postoperative external rotation [31]. Immediate postoperative physical therapy may also help to regain external rotation and limit loss of motion [31].

The incidence of nonunion or fibrous union has been reported up to 9% after a Latarjet procedure [5]. They are commonly incidental findings and are unlikely to lead to recurrence of instability or require reoperation. These patients often report good to excellent functional outcomes following surgery [2, 5, 20]. To obtain good compression and better healing potential, the anterior-inferior glenoid rim and underside of the coracoid graft should be decorticated to flat surfaces. Placement of screws parallel to the glenoid face will also reduce the incidence of graft nonunion [2].