Review Question - QID 213149

The arrow in Figure A depicts the middle glenohumeral ligament (MGHL). The MGHL resists anterior and posterior translation of the humerus at the midrange of abduction, at 45 degrees.

The MGHL is a static glenohumeral ligament, originating from the anterior glenoid labrum, running obliquely across the subscapularis, and inserting just medial to the humeral lesser tuberosity. There are several normal variants of the MGHL, including the cord-like MGHL in the Buford complex. Thus, it is important to recognize it and differentiate it from the superior glenohumeral ligament (SGHL), inferior glenohumeral ligament (IGHL), and subscapularis during arthroscopic procedures.

Wang et al. performed a basic science study on the pathomechanics of acquired shoulder instability. They highlighted the anatomy of the static glenohumeral ligaments, reporting them to be complex and variable, with their function significantly dependent on the position of the humerus with respect to the glenoid.

Itoigawa et al. published a review on the anatomy of the capsulolabral complex and rotator interval related to glenohumeral instability. They reported that the MGHL was the most variable ligament among the glenohumeral ligaments. They emphasized that knowledge of the detailed anatomy and anatomical variations is essential for the orthopedic surgeon in understanding the pathology, which results in accurate diagnosis of instability, and ultimately correct treatment options.

Figure A depicts the glenohumeral joint, viewed from the posterior arthroscopic portal in a lateral decubitus position. Illustration A depicts labeled anatomic structures visualized during shoulder arthroscopy.

Incorrect Answers:
Answer 1: This describes the function of the SGHL.
Answer 3: This describes the function of IGHL.
Answer 4: This describes the function of the coracohumeral ligament.
Answer 5: This describes the function of the subscapularis tendon.