Biomechanical analysis of medial tibial cartilage by 7T magnetic resonance imaging and digital volume correlation: a preliminary study of variations caused meniscus ramp lesions.

Abstract

The objective study was to compare medial tibial stress variations in three different situations: (1) on native knees, (2) after performing medial meniscus ramp lesions then (3) after their arthroscopic treatments with all-inside suture or total menisectomy. We performed a biomechanical cadaveric study on specimens with a normal knee joint line alignment and without meniscal and/or cartilaginous injuries. The comparison of medial tibial stress variations was measured by a digital volume correlation (DVC) method using 7 Tesla MRI images at different loadings as close as possible to physiological conditions (1500 N). We observed that medial tibial cartilage deformation and mechanical response, and thus the thickness of the cartilage, are restored in the case of all-inside arthroscopic suture whereas they increase in the case of menisectomy. Medial menisectomy increases medial tibial cartilage displacement fields in physiological compression, whereas all-inside arthroscopic suture allows to get closer to the initial conditions before medial meniscus ramp lesion. This biomechanical study suggests that ramp lesions are potentially at risk of osteoarthritic evolution and that its repair would make it possible to reduce the risks associated with increased stress on the medial tibial cartilage.