Meniscal centralization restores meniscus-cartilage contact mechanics after posterior root repair: a biomechanical in-silico study.

BACKGROUND: Meniscal posterior root tears can be effectively treated with root repair surgery. However, this isolated approach often fails to correct concomitant meniscal extrusion. Meniscal centralization has therefore emerged as a solution to address this limitation. Despite preliminary clinical evidence showing that centralization can delay knee osteoarthritis (KOA) progression over two years, the biomechanical mechanism underlying this clinical benefit remains uninvestigated.

METHODS: We constructed a knee joint finite element model using a well-established modeling strategy. After validating the model, we generated two surgical scenarios: isolated posterior root repair and repair combined with meniscal centralization. Under different directional compressive loads, we compared the maximum displacement of the medial meniscus and the corresponding contact area between the meniscus and the medial tibial cartilage.

RESULTS: A consistent trend was observed under different directional compressive loads. Specifically, in the meniscus posterior root repair model, meniscus displacement increased while the contact area between the meniscus and tibial cartilage decreased. In contrast, although meniscus displacement in the centralization model was even lower than that in the control group, the contact area was comparable between the two models.

CONCLUSION: Meniscus centralization limits meniscal displacement, thereby reducing extrusion and increasing the contact area between the meniscus and tibial cartilage. These conclusions are biomechanical inferences drawn under the premise that the centralization surgery provides rigid constraint of the meniscus. They have not yet been validated by large-sample prospective clinical trials, an issue that should be addressed in subsequent studies.