Magnetic Resonance Imaging Appearance of a Repaired Capsulolabral Complex after Arthroscopic Bankart Repair

Abstract

Background Revision Bankart operations frequently show capsulolabral buttress loss and recurrent soft tissue Bankart lesion. Capsulolabral augmentation is designed to increase glenohumeral stability by 2 separate mechanisms: deepening the glenoid concavity and reducing capsular laxity. This is accomplished by shifting the capsule to buttress the glenoid labrum. Hypothesis A retained capsulolabral buttress may show loss of height and slope at a certain period after surgery, regardless of stability. Thus, the authors wanted to confirm the importance of an intraoperative establishment of capsulolabral buttress in terms of stability. Study Design Case-control study; Level of evidence, 3. Methods Arthroscopically repaired Bankart lesions in 21 consecutive shoulders that showed no frank dislocation were evaluated using axial and oblique coronal T2-weighted magnetic resonance imaging at 3 timepoints (preoperative period, average postoperative week 6 and a nearly full range of motion recovery, and postoperative month 6 with a return to daily activity). The authors measured 2 parameters (height and slope) on axial (mainly capsulolabral containment) and oblique coronal images (mainly inferior glenohumeral ligament) at the anteroinferior portion of the glenoid (5 mm above the most inferior anchor). In addition, they compared the above-mentioned parameters at postoperative month 6 by magnetic resonance imaging in 21 controls and in 21 patients whose instability recurred after surgery (not included in the prospective study). Results There was a significant increase between the preoperative period and postoperative week 6 in all 4 parameters (P < .0001). There was also a significant increase between the preoperative period and postoperative month 6 in all 4 parameters (P < .0001). However, no statistically significant difference was observed between postoperative week 6 and postoperative month 6 in all 4 parameters (P > .1). Furthermore, significant differences were observed between normal controls and patients with recurrent instability (P < .001) and between the authors’ cases and patients with recurrent instability not in the study (P < .001). However, no difference was observed between their cases and normal shoulders (P > .1). Conclusion After suture anchor Bankart repair, initial capsulolabral buttress property was maintained at 6 months postoperatively. Furthermore, the buttress was more prominent in stable and normal shoulders than in recurrent instability shoulders. Therefore, the authors believe that the establishment of a capsulolabral buttress is meaningful during Bankart repair.