Glenoid Fracture After Arthroscopic Bankart Repair: Case Series and Biomechanical Analysis

To examine whether anchors used in arthroscopic Bankart repair increased the risk of subsequent fracture, six intact polyurethane scapulae and six with three 3.0-mm suture anchors placed along the anteroinferior glenoid were compared. An axial load of 1 mm/s was applied to the anteroinferior glenohumeral joint with a prosthetic humeral head. Outcome measures were force needed for initial fracture and catastrophic failure, percent of anterior glenoid bone loss, and fracture length. With the numbers available, no significant differences could be detected between groups in yield load or maximum load. The anchor group had a significantly larger percentage of bone loss (p <.01) and fracture length (p < .01) compared to the intact group. In this study, anchors did not decrease force needed to fracture but did lead to significantly larger fractures of the anterior glenoid during a simulated dislocation event. Further study using various anchors and techniques is warranted. Key words: anchors, arthroscopy, Bankart repair, biomechanics, glenoid fracture, shoulder dislocation, shoulder instability