Anterior horn lateral meniscus tears on MRI: imaging features, demographics, and surgical correlation.

Abstract

Purpose: This study aimed to provide a descriptive analysis of anterior horn of the lateral meniscus (AHLM) tears on magnetic resonance imaging (MRI), including demographics, tear morphology, additional meniscal findings, ligamentous injury, and surgical management.

Material and methods: Radiology database search identified AHLM tears. Inclusion criteria: Presence of AHLM tear and age 12-70 years old. Exclusion criteria: No tear, incorrect/incomplete MRI protocol, knee surgery, advanced cartilage loss, and non-AHLM predominant tear. Tear morphology, associated features, and ligamentous injury were recorded. Chart review included age, biologic gender, and surgical management. Statistical analyses evaluated differences across tear morphology groups with adjustment for multiple comparisons.

Results: Fifty-five patients were included (28 females, 27 males; median age 54.0 years). Tear morphologies included horizontal (41.8%), complex/macerated (21.8%), radial (21.8%), and vertical (14.6%). Meniscal flap was present in 14.6% and intrameniscal/parameniscal cyst formation in 32.7%. Concurrent ligamentous injury was identified in 27.3%. Thirteen patients (23.6%) underwent operative management, of whom eight (14.6%) underwent AHLM surgery. Radial tears demonstrated the highest proportion of surgical management (58.3%) and ligamentous injury (41.7%). Significant differences were observed across tear morphology groups for age and gender distribution, with radial tears occurring more frequently in younger male patients and complex/macerated tears occurring more frequently in older patients (adjusted p < 0.05).

Conclusions: Radial tears were more frequently observed in younger male patients and were more often managed surgically. Complex/macerated tears were more frequently observed in older patients. Prospective studies with arthroscopic correlation are required to better define the clinical significance of AHLM tear subtypes.