Background: For a successful outcome of arthroscopic Bankart repair, it is necessary to insert a suture anchor inside the glenoid bone. The purpose of the present study was to measure the angle and placement of bone holes for the anchors from postoperative computed tomography (CT) scans of scapula.
Methods: Ten shoulders of nine consecutive patients (six male, 3 female; mean age: 25.4) who underwent arthroscopic Bankart repair were involved. All anchors were inserted through the anterosuperior portal after establishing a bone hole by drill. CT images of the scapula were taken within 18 months postoperatively. After creating 3-D scapula models from those data, all bone holes were divided into 2 groups: Success (S) group which was placed inside the glenoid bone till the end point, and Failure (F) group which penetrated the glenoid bone. In addition, the angle between glenoid articular surface and the bone hole were measured at the coronal and the transverse plane views.
Results: A total of 40 drill holes were investigated in the inferior area. The penetration was shown in all the four holes (100 %) in posteroinferior area and six holes of the 18 holes (33.3%) in anteroinferior region. The angle at coronal plane view in S group was significantly larger than F group, whereas no significant differences were noted in the transverse plane view.
Conclusion: A drill hole should be created carefully around posteroinferior position. Furthermore, the angle between drill guide and the glenoid surface at the coronal plane view should be given attention during the operation.
