Factors Associated With Humeral Avulsion of Glenohumeral Ligament Lesions in Patients With Anterior Shoulder Instability: An Analysis of the MOON Shoulder Instability Cohort

Ryan D Freshman; Alan L Zhang; C Benjamin Ma; Brian T Feeley; Shannon Ortiz; Jhillika Patel; Warren Dunn; Brian R Wolf; Carolyn Hettrich; Drew Lansdown; MOON Shoulder Group collaborators; Keith M Baumgarten; Julie Y Bishop; Matthew J Bollier; Robert H Brophy; Jonathan T Bravman; Charles L Cox; Gregory L Cvetanovich; John A Grant; Rachel M Frank; Grant L Jones; John E Kuhn; Scott D Mair; Robert G Marx; Eric C McCarty; Bruce S Miller; Adam J Seidl; Matthew V Smith; Rick W Wright

doi:10.1177/23259671231206757

Factors Associated With Humeral Avulsion of Glenohumeral Ligament Lesions in Patients With Anterior Shoulder Instability: An Analysis of the MOON Shoulder Instability Cohort

Orthop J Sports Med. 2023 Oct 27;11(10):23259671231206757. doi: 10.1177/23259671231206757. eCollection 2023 Oct.

Authors

Ryan D Freshman¹, Alan L Zhang¹, C Benjamin Ma¹, Brian T Feeley¹, Shannon Ortiz², Jhillika Patel³, Warren Dunn⁴, Brian R Wolf¹, Carolyn Hettrich³, Drew Lansdown¹; MOON Shoulder Group collaborators; Keith M Baumgarten⁵, Julie Y Bishop⁶, Matthew J Bollier², Robert H Brophy⁷, Jonathan T Bravman⁸, Charles L Cox⁹, Gregory L Cvetanovich⁶, John A Grant¹⁰, Rachel M Frank⁸, Grant L Jones⁶, John E Kuhn⁹, Scott D Mair¹¹, Robert G Marx¹², Eric C McCarty⁸, Bruce S Miller¹⁰, Adam J Seidl⁸, Matthew V Smith⁷, Rick W Wright⁹

Affiliations

¹ Department of Orthopedic Surgery, University of California-San Francisco, San Francisco, California, USA.
² University of Iowa, Iowa City, Iowa, USA.
³ Brigham and Women's Hospital, Boston, Massachusetts, USA.
⁴ Fondren Orthopedic Group, Houston, Texas, USA.
⁵ Orthopedic Institute of Sioux Falls, Sioux Falls, South Dakota, USA.
⁶ The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.
⁷ Washington University, St Louis, Missouri, USA.
⁸ University of Colorado School of Medicine, Aurora, Colorado, USA.
⁹ Vanderbilt University Medical Center, Nashville, Tennessee, USA.
¹⁰ MedSport, University of Michigan, Ann Arbor, Michigan, USA.
¹¹ University of Kentucky, Lexington, Kentucky, USA.
¹² Hospital for Special Surgery, New York, New York, USA.

Abstract

Background: Humeral avulsion of the glenohumeral ligament (HAGL) lesions are an uncommon cause of anterior glenohumeral instability and may occur in isolation or combination with other pathologies. As HAGL lesions are difficult to detect via magnetic resonance imaging (MRI) and arthroscopy, they can remain unrecognized and result in continued glenohumeral instability.

Purpose: To compare patients with anterior shoulder instability from a large multicenter cohort with and without a diagnosis of a HAGL lesion and identify preoperative physical examination findings, patient-reported outcomes, imaging findings, and surgical management trends associated with HAGL lesions.

Study design: Cross-sectional study; Level of evidence, 3.

Methods: Patients with anterior glenohumeral instability who underwent surgical management between 2012 and 2020 at 11 orthopaedic centers were enrolled. Patients with HAGL lesions identified intraoperatively were compared with patients without HAGL lesions. Preoperative characteristics, physical examinations, imaging findings, intraoperative findings, and surgical procedures were collected. The Student t test, Kruskal-Wallis H test, Fisher exact test, and chi-square test were used to compare groups.

Results: A total of 21 HAGL lesions were identified in 915 (2.3%) patients; approximately one-third (28.6%) of all lesions were visualized intraoperatively but not identified on preoperative MRI. Baseline characteristics did not differ between study cohorts. Compared with non-HAGL patients, HAGL patients were less likely to have a Hill-Sachs lesion (54.7% vs 28.6%; P = .03) or an anterior labral tear (87.2% vs 66.7%; P = .01) on preoperative MRI and demonstrated increased external rotation when their affected arm was positioned at 90° of abduction (85° vs 90°; P = .03). Additionally, HAGL lesions were independently associated with an increased risk of undergoing an open stabilization surgery (odds ratio, 74.6 [95% CI, 25.2-221.1]; P < .001).

Conclusion: Approximately one-third of HAGL lesions were missed on preoperative MRI. HAGL patients were less likely to exhibit preoperative imaging findings associated with anterior shoulder instability, such as Hill-Sachs lesions or anterior labral pathology. These patients underwent open procedures more frequently than patients without HAGL lesions.

Keywords: humeral avulsion of the glenohumeral ligament; magnetic resonance imaging; risk factors; shoulder instability.

Grants and funding

U54 TR001356/TR/NCATS NIH HHS/United States