Biomechanical Effectiveness of the Latarjet Procedure Versus a Contoured Structural Bone Graft

A significant glenoid bone defect limits the effectiveness of arthroscopic repairs of traumatic anteroinferior shoulder instability. The critical size of the defect, above which an arthroscopic Bankart repair becomes ineffective, has been estimated by Itoi et al20 to be an average width of 6.8 mm, or 21 % of the glenoid length. In defects of this size, the translational force required to subluxate the humeral head in abduction and external rotation is significantly decreased. If a critical bony glenoid defect is not addressed along with arthroscopic capsulolabral refixation, the risk of redislocation is increased, resulting in recurrence rates reported to range from 56 % to 67%.6,38 Biomechanically, a glenoid bone defect has 2 consequences: first, the loss of a part of the glenoid rim will cause the glenoid to be shallower and therefore less resistant to shear forces that might tend to cause dislocation; and second, the arc lengt