Analysis of MR Arthrogram Versus Arthroscopy in Glenoid Labral Tear Diagnosis: Identifying Pitfalls to Improve Radiologic Accuracy

Abstract

Bennett Francis Dwan, Alexander Kui, Perry Veras, Amirmasoud Negarestani, Brett Ploussard and Emad Allam*

Background: Magnetic Resonance (MR) arthrogram is the preferred diagnostic imaging study for detecting glenoid labral tears. Despite this, there is still discrepancy between MR arthrogram and arthroscopy, the diagnostic gold standard. We aim to identify areas of discordance between imaging findings and surgical findings to aid radiologists in a more accurate diagnosis of glenoid labral tears.

Methods: A retrospective chart review was conducted at our institution on a population that underwent an MR arthrogram and then underwent shoulder arthroscopy within six months. Factors such as patient demographics, location of labral tear, and radiologist and surgeon experience were collected.

Results: Analysis revealed a labral tear discrepancy rate of 14% and a labral tear location discrepancy rate of 39%. Labral tear discrepancies occurred at a significantly higher rate in older patients (p=0.035) and females (p= 0.018). Discrepancies were most common in the superior and anterosuperior zones of the labrum. Increased radiologist experience was associated with decreased discrepancies (p=0.01). Increased surgeon experience was associated with increased discrepancies (p=0.03).

Conclusion: Awareness of various factors associated with discrepancies, such as the patient demographic and labral tear location, should prompt radiologists and surgeons to pay particular attention to those cases and thus improve clinical decision-making.