A detailed 3D volumetric magnetic resonance arthrographic analysis in a spiral ligament and anteroinferior capsuloligamentous complex of the shoulder joint.

OBJECTIVES

This study aimed to delineate the anatomical characteristics of the spiral glenohumeral ligament (SpiGHL), middle glenohumeral ligament (MGHL), and anterior band of inferior glenohumeral ligament (AB-IGHL), as well as their potential interrelationships, using MR arthrographic images from a large patient population.

METHODS

All patients underwent 3D volumetric magnetic resonance (MR) arthrography sequences in addition to conventional MR imaging. All MR arthrography images were retrospectively assessed by two radiologists with expertise in arthrography. The origins and insertions of SpiGHL, MGHL, and AB-IGHL, along with any variations and interrelationships, were carefully examined and documented. These findings were statistically analyzed according to the patient's age, gender, and laterality of the shoulder (right or left).

RESULTS

The study included 190 shoulder MR arthrographies, identifying SpiGHL in 15 patients (7.9%). Among the 190 patients, 20 (10.5%) had an AB-IGHL with a high insertion on the anterior glenoid margin. In 10 of 15 patients with SpiGHL (66.6%), a conjugation of SpiGHL and MGHL was observed. MGHL hypoplasia was observed in 11 MR arthrographies. Of the 11 patients, 5 (45.5%) also presented with SpiGHL. The incidence of SpiGHL was significantly higher in the group with hypoplastic MGHL. Additionally, the average age of patients with a high-origin AB-IGHL was significantly lower than that of patients without this feature.

CONCLUSIONS

Knowing the anterior capsuloligamentous detailed anatomy of the shoulder joint and its possible variations is important in correctly interpreting the pathologies of this region. The spiral GHL and its possible relationship with other ligaments can be defined in detail on MR arthrography.