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Updated: Aug 25, 2025
Destabilization of the Medial Meniscus and Cartilage Scratch Murine Model of Accelerated Osteoarthritis
Published on: July 6, 2022
Development and Analysis of Mouse Medial Meniscus Posterior Root Tear Model
Koji Nukuto1, Takehiko Matsushita2, Kohei Kamada1
1Department of Orthopaedic Surgery, Graduate School of Medicine, Kobe University, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Abstract:
Medial meniscus posterior root tears (MMPRT) are often associated with osteoarthritis (OA) progression and subchondral bone insufficiency fractures. This study aimed to develop the first MMPRT mouse model. The MMPRT model was created by sectioning the medial meniscus posterior root of 12-week-old CL57BL/6J male mice under stereomicroscopic observation. The sham operation and the destabilization of the medial meniscus (DMM) model groups were also created. OA progression and subchondral bone changes were evaluated histologically using the Osteoarthritis Research Society International (OARSI) subchondral bone scoring system at 2, 4, 8, and 12 weeks after surgery. Microcomputed tomography (µCT) was performed to evaluate the presence of insufficient fractures. OA progression and medial meniscus extrusion were observed in the MMPRT and DMM models 12 weeks after surgery. OA progressed in both models during the time course, without a significant difference in the OARSI score between the two groups. The subchondral bone score was significantly higher at 12 weeks than at 2 and 4 weeks in the MMPRT group, while no significant difference was found between the two groups. In the µCT analysis, destruction of the medial tibial plateau was observed in 4/40 knees, while none were observed in the DMM group. Of the four knees, destruction of the medial femoral condyle was also observed in three knees. Characteristic pathological changes were observed in the mouse MMPRT model. The mouse MMPRT model may be useful for investigating pathological changes after MMPRT.
Insights
Researchers developed a new mouse model for medial meniscus posterior root tears (MMPRT), which are linked to osteoarthritis progression. This model effectively replicates key pathological changes, offering a valuable tool for future research into MMPRT and related conditions.
Area of Science:
- Orthopedics
- Biomedical Engineering
- Osteoarthritis Research
Background:
- Medial meniscus posterior root tears (MMPRT) are frequently linked to osteoarthritis (OA) progression and subchondral bone insufficiency fractures.
- Existing research lacks a dedicated animal model for MMPRT to study these associated pathologies.
Purpose of the Study:
- To develop and characterize the first mouse model for medial meniscus posterior root tears (MMPRT).
- To evaluate OA progression and subchondral bone changes in the novel MMPRT model.
- To compare the MMPRT model with the destabilization of the medial meniscus (DMM) model.
Main Methods:
- Mice underwent surgical sectioning of the medial meniscus posterior root to create the MMPRT model.
- Sham operation and DMM model groups served as controls.
- Osteoarthritis Research Society International (OARSI) scoring and microcomputed tomography (µCT) were used for histological and structural analysis at 2, 4, 8, and 12 weeks post-surgery.
Main Results:
- Both MMPRT and DMM models exhibited OA progression and medial meniscus extrusion by 12 weeks.
- Subchondral bone scores significantly increased in the MMPRT group over time.
- Microcomputed tomography revealed medial tibial plateau destruction in 4/40 knees within the MMPRT group, with associated medial femoral condyle destruction in three of those knees.
Conclusions:
- The developed mouse MMPRT model demonstrates characteristic pathological changes relevant to human MMPRT.
- This model shows potential for investigating the pathological mechanisms and consequences of MMPRT, including subchondral bone destruction.
- The MMPRT model provides a valuable platform for preclinical studies on treatments for meniscus tears and associated osteoarthritis.
