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Time-Dependent Increase in Medial Meniscus Extrusion Predicts the Need for Meniscal Repair in Patients with Partial
Koki Kawada1, Takayuki Furumatsu1, Masanori Tamura1
1Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8558 Japan.
Purpose:
This study aimed to compare medial meniscus extrusion (MME) in patients with partial medial meniscus posterior root tears (MMPRTs) through magnetic resonance imaging (MRI) conducted at two-time points and to determine whether patient characteristics or MME measurements differ in patients who respond to nonoperative treatment compared with those who require surgical treatment.
Methods:
Thirty-seven patients with partial MMPRTs underwent two MRI scans during nonoperative management or before pull-out repair. Among these, 17 patients received nonoperative management, and 20 underwent pull-out repair. Partial MMPRTs were diagnosed based on the MRI findings. MME measurements were performed on both MRI scans. Statistical and receiver operating curve (ROC) analyses were performed.
Results:
The duration between the two MRI scans was significantly shorter in the pull-out repair group than in the nonoperative management group. The increase in MME (ΔMME) on MRI scans was significantly greater in the pull-out repair group than in the nonoperative management group. Linear regression analysis revealed a weak correlation between the MRI interval and ΔMME in the nonoperative management group and a moderate correlation in the pull-out repair group. In the ROC construction, the cut-off value for ΔMME that requires surgical intervention was 0.41 mm, with a sensitivity and specificity of 85.0% and 52.9%, respectively.
Conclusion:
Patients with partial MMPRTs requiring surgical treatment had greater MME progression in a shorter time and a time-dependent increase in MME. Therefore, a ΔMME of ≥ 0.41 mm may be useful in deciding surgical intervention based on MRI retests.
Level Of Evidence:
III.
Insights
Medial meniscus extrusion (MME) progression on MRI indicates the need for surgery in partial medial meniscus posterior root tears (MMPRTs). An increase of ≥0.41 mm in MME may guide surgical decisions.
Area of Science:
- Orthopedic surgery
- Radiology
- Sports medicine
Background:
- Partial medial meniscus posterior root tears (MMPRTs) are a common cause of knee pain.
- Medial meniscus extrusion (MME) on MRI is a potential indicator of MMPRT severity.
- Understanding MME changes can help differentiate treatment pathways.
Purpose of the Study:
- To compare MME in patients with partial MMPRTs using serial MRIs.
- To determine if MME measurements differ between nonoperative and surgical treatment groups.
- To identify MME thresholds predictive of surgical necessity.
Main Methods:
- Retrospective analysis of 37 patients with partial MMPRTs.
- Serial MRI scans were obtained for MME measurement.
- Statistical analyses, including ROC curve analysis, were performed.
Main Results:
- The surgical group showed a significantly greater increase in MME (ΔMME) over a shorter interval compared to the nonoperative group.
- A ΔMME of ≥0.41 mm was identified as a threshold for surgical intervention with 85.0% sensitivity.
- Correlation analysis showed a moderate association between MRI interval and ΔMME in the surgical group.
Conclusions:
- Greater MME progression over time is associated with the need for surgical treatment in partial MMPRTs.
- A ΔMME threshold of 0.41 mm on serial MRI may aid in surgical decision-making.
- Serial MRI monitoring of MME can provide valuable prognostic information for partial MMPRTs.
