Vascularization Characteristics of the Different Meniscal Layers: Three-Dimensional Assessment With Micro-CT

Background: Degenerative meniscal lesions are often characterized by horizontal cleavage tears, and there is currently no established gold standard for treating these injuries. Understanding the vascularization and distribution of blood vessels along the meniscal layers could offer valuable insights into the management and healing of these tears. Hypothesis: Distinct vascularization patterns could be identified in different layers of the meniscus along the proximal-distal axis, providing new insights and potentially expanding or refining existing classification systems. Study Design: Descriptive laboratory study. Methods: To visualize the meniscal microvasculature, human cadaveric legs were perfused with a polymer-based contrast agent, followed by micro–computed tomography imaging. The menisci were virtually divided into transverse (layers), radial (thirds), and circumferential zones to quantify the vascular contribution of each zone and to evaluate vascular parameters such as segment diameter, tortuosity, and the number of vessel segments. Results: In the medial meniscus, the inferior surface of the outermost zone and the intermediate layers of the peripheral zones showed a potential reduction in vessel percentage. In the lateral meniscus, a relatively higher percentage of vessels was observed from the superficial to the inferior layers of the posterior horn, extending into the inner zones. Additionally, the lateral meniscus exhibited a greater number of vessels with smaller diameters compared with the medial meniscus. Conclusion: This micro-computed tomography approach for analyzing spatial vascular distribution offers a more comprehensive view of meniscal vasculature across multiple planes and regions. Clinical Relevance: This study may pave the way for new classifications that identify highly and poorly vascularized regions of the meniscus, potentially improving the effectiveness of treatments for meniscal injuries, ultimately reducing recovery time and improving long-term joint health for patients.