Anterior Bankart Repair With Superior Capsular Plication Causes Increased Mean Tension in Posterior Glenohumeral Capsule.

PURPOSE

The purpose of this study is to investigate if a biomechanical difference exists in the prerepair and postrepair states of the posterior inferior glenohumeral ligament (PIGHL) following anterior Bankart repair with respect to capsular tension, labral height, and capsular shift.

METHODS

In this study, 12 cadaveric shoulders were dissected to the glenohumeral capsule and disarticulated. The specimens were loaded to 5-mm displacement using a custom shoulder simulator, and measurements were taken for posterior capsular tension, labral height, and capsular shift. We measured the capsular tension, labral height, and capsular shift of the PIGHL in its native state and following repair of a simulated anterior Bankart lesion.

RESULTS

We found that there was a significant increase in the mean capsular tension of the posterior inferior glenohumeral ligament (Δ = 2.12 ± 2.10 N;  = .005), as well as posterior capsular shift (Δ = .362 ± 0.365 mm;  = .018). There was no significant change in posterior labral height (Δ = 0.297 ± 0.667 mm;  = .193). These results demonstrate the sling effect of the inferior glenohumeral ligament.

CONCLUSION

Although the posterior inferior glenohumeral ligament is not directly manipulated during an anterior Bankart repair, when the anterior inferior glenohumeral ligament is plicated superiorly, some of the tension is transmitted to the posterior glenohumeral ligament as a result of the sling effect.

CLINICAL RELEVANCE

Anterior Bankart repair with superior capsular plication results in an increased mean tension of the PIGHL. Clinically, this may contribute to shoulder stability.