2025 ISAKOS Biennial Congress ePoster
Medial Meniscus Tears with Grammar Signs Benefit from Operative Intervention in the Setting of Early Arthritis
Lydia Mckeithan, MD, Sacramento, CA UNITED STATES
Shannon Tse, BMBS, Sacramento, CA UNITED STATES
Matthew Frederickson, MD, Sacramento, CA UNITED STATES
Jingyanshan Li, MD, Sacramento, California UNITED STATES
Cassandra Lee, MD, Sacramento, CA UNITED STATES
University of California, Davis, Sacramento, California, UNITED STATES
FDA Status Not Applicable
Summary
Meniscal “grammar signs” are tear patterns seen on MRI, often with concomitant early arthritis, that present with mechanical symptoms and have favorable outcomes with operative management.
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Abstract
Introduction
Arthroscopic partial meniscectomy (APM) for meniscus tears with concomitant degenerative joint disease remains a topic of debate. Meniscal “grammar signs” are distinct tear patterns on MRI, described as inferior or superior displacement of a parrot beak flap tear into the medial gutter. Our study aimed to characterize clinical findings associated with “grammar signs”, particularly medial compartment articular degeneration, and compare operative versus non-operative management.
Methods
A retrospective review was conducted on patients with medial meniscus tears at a single institution (July 2018 to August 2023). T2-weighted coronal images were reviewed to identify patients with a meniscal “grammar sign” and plain radiographs reviewed for osteoarthritis stage. Associated chondromalacia was noted from MRI and operative reports. Clinical characteristics and outcomes were determined by reviewing charted H&P and follow-up notes.
Results
Out of 41 patients with a “grammar sign”, 27 (65.9%) underwent APM. 14 patients (51.9%) in the operative group presented with mechanical symptoms, compared to only 2 (14.3%) in the non-operative group (X2=5.47, p=0.019). 29 patients (74.4%) had arthritis KL stages 1-2. 27 patients (65.9%) had medial chondromalacia per radiology report. The distribution of arthritis and chondromalacia grades did not differ between treatment groups. Per operative reports, most patients had varying ICRS chondromalacia grades in the medial compartment (74.1%). Most patients who underwent APM had minimal (56%) to no pain (29%) at final follow-up. The operative group had significantly lower pain ratings at final follow-up (X2=14.7, p=0.0021).
Discussion
This study is the largest to comprehensively assess clinical findings and outcomes associated with meniscal “grammar signs”. Pain refractory to conservative management and mechanical symptoms are important factors when indicating patients for surgery. Although “grammar signs” have a close association with grade 1-3 chondromalacia, the decreased pain with operative intervention suggests favorable outcomes with APM, even in the setting of early osteoarthritis.