Comparison of the Biomechanical Behavior of a Soft Bankart Lesion on Shoulder Ligaments During Abduction: A Finite Element Study

The soft Bankart lesion is characterized by the abnormal translation of the humeral head during dislocation, which places excessive stress on the labrum and causes it to stretch along with other structures that provide joint stability. This lesion is described as a purely soft tissue injury and occurs due to the detachment of the anteroinferior labroligamentous complex. This research aimed to evaluate the computational biomechanics of a biomodel of the shoulder joint with a soft Bankart lesion during pure abduction using the Finite Element Method (FEM). It evaluates the tissue mechanics of the structures with the lesion, such as ligaments, the articular capsule, and the labrum, which guide and limit the bones of the joint during movement. A healthy shoulder joint biomodel is developed for comparison. The results of stress and strain in the healthy shoulder and the soft Bankart biomodel are analyzed. The results for the soft Bankart biomodel show an increase in stress on the MGHL, with the pIGHL assuming a primary stabilizing role. The CHL and articular capsule limit the excessive displacement of the humeral head.