Repairing the Capsule to the Transferred Coracoid Preserves External Rotation in the Modified Latarjet Procedure.

BACKGROUND It is not clear whether the anterior capsule should be repaired to the coracoid process or to the native glenoid during the modified Latarjet procedure. We investigated joint stability and range of motion of the shoulder after the modified Latarjet procedure with both of these methods of capsular repair. METHODS Eighteen fresh-frozen cadaveric shoulders were used. After a Bankart lesion and 6-mm glenoid defect were created, the coracoid process was transferred to the glenoid and fixed with screws. The anterior capsule was repaired either to the coracoid process (coracoid group) or to the native glenoid (glenoid group). The ranges of internal and external axial rotation were measured with the arm at 0° and 60° of glenohumeral abduction. The range of motion was measured with a constant torque of 200 N-mm. Joint stability was measured using a custom stability testing device. The stability ratio in the anterior-posterior direction was measured with the arm at maximal external rotation and neutral rotation. RESULTS The range of external rotation was greater at both 0° and 60° of abduction in the coracoid group compared with the glenoid group (p < 0.05). The range of internal rotation was not significantly different between groups. The end-range stability ratio was not significantly different between groups, but the mid-range stability ratio was significantly greater in the glenoid group. CONCLUSIONS Because the difference in the mid-range stability may not be clinically relevant, we recommend repairing the capsule to the coracoid, as that preserves the range of motion in external rotation. CLINICAL RELEVANCE Repairing the capsule to the transferred coracoid during the modified Latarjet procedure appears to be beneficial to avoid the limited range of motion in external rotation, but the direct contact of the humeral head and the transferred coracoid might confer a risk of osteoarthritis. Long-term consequences in the clinical setting need to be clarified.