Evaluation of Inferior Glenohumeral Ligament Labral Complex After Arthroscopic Bony Bankart Repair Using Abduction and External Rotation MRI

Abstract

Our concept is tensioning of IGHL/LC rather than reduction of a bony fragment in arthroscopic bony Bankart repair. The purpose of this study was to evaluate the condition of IGHL/LC and to investigate the factors affecting this condition. Twenty-seven patients, 28 shoulders, with recurrent anterior instability treated by arthroscopic bony Bankart repair were enrolled. We measured the position of the humeral head center by ABER MRI and evaluated the attachment site, inclination and thickness of IGHL/LC by point rating. Then, the bone loss of glenoid, the size of bony fragment and its displacement were measured from 3D-CT images. The humeral head center was located 8 +/- 8% posteriorly relative to the glenoid center in ABER MRI. The inclination of IGHL/LC was correlated with the position of the humeral head center, and the higher inclination of IGHL/LC showed that the humeral head center was located more posteriorly. But the inclination of IGHL/LC was not correlated with the size of the bony fragment or bone loss of the glenoid.
The tensioning of IGHL/LC was necessary for the control of the humeral head center posteriorly. Its tensioning may not only be influenced by the bone loss of the glenoid and the size of fragment but also by the condition of IGHL/LC.