Classic Versus Congruent-Arc Latarjet Procedures

Glenohumeral instability remains a frequent pathology, specifically in athletes and active patients. As such, several treatment options have been described. In the setting of significant glenoid bone loss (i.e., >20%), off-track Hill-Sachs lesions, and failed previous soft-tissue-based repairs, glenoid bone-augmentation techniques must be considered. These techniques restore stability by a triple blocking effect of the bony graft, the capsulolabral complex repair, and the dynamic sling effect of the conjoined tendon. The classic Latarjet procedure consists in performing a coracoid osteotomy along with the conjoined tendon attachment followed by transfer and fixation to the anterior glenoid, positioning the lateral surface of the coracoid to be flush with the articular side. Then, a modification of this technique defined as "congruent-arc Latarjet" (CAL) was described. This approach involves rotating the coracoid process 90° along its longitudinal axis using the inferior surface to recreate the native glenoid arc. Biomechanical studies have discussed advantages and disadvantages of these techniques. The CAL allows a greater glenoid surface area, which may be relevant in patients with increased glenoid bone loss. However, the bone contact area is reduced, which increases the technical difficulty of screw positioning with an increased risk of graft fragmentation. The classic Latarjet technique has a greater initial fixation strength between the graft and the glenoid and a greater potential for bone consolidation due to the broader contact bone area. Excellent clinical and sports outcomes with low recurrence rates have been observed in both techniques. Imaging findings have exhibited high bone block healing and no difference in graft placement, but CAL demonstrated a greater incidence of fibrous or nonunion rates and errors in screw fixation. Finally, while similar early complications have been reported, long-term outcomes are still needed in CAL for comparing osteoarthritis progression. These results emphasize that either technique can be considered to manage glenohumeral instability when appropriately indicated.