Avaliação biomecânica das lesões ligamentares do complexo articular de Lisfranc: novo modelo cadavérico utilizando estresse em supinação e pronação

Abstract

Introduction: Lesions in the Lisfranc joint complex occur due to direct or indirect trauma, where a torsional or axial force is transmitted to the foot. Cadaveric models are a useful way to assess injury patterns and fixation models, but a frequent limitation is the amount of joint dislocation after injury. The aim of this study was to test a cadaveric model that includes axial load, plantar flexion of the foot and pronation-supination movement, recreating bone diastasis similar to that observed in subtle Lisfranc lesions in clinical practice. Our hypothesis is that the application of pronation and supination motion in a cadaveric model would produce reliable and measurable bone displacements. Methods: Twenty-four fresh frozen cadaveric leg samples were used. The medial (C1) and intermediate (C2) cuneiform bones, the first (M1) and second (M2) metatarsal bones were marked. A complete ligament injury was performed between C1-C2 and C1-M2 in 12 samples (Group 1) and between C1-C2, C1-M2, C1-M1 and C2-M2 in 12 corresponding samples (Group 2). Foot pronation and supination, in addition to an axial load of 400 N, were applied to the samples. A 3D scanner was used to measure the distances between the bones. Results: For the partial lesion group (Group 1), in which the ligaments between C1-C2 and C1-M2 were injured, these distances increased in the injured condition in both pronation and supination, as expected. Regarding the distance C2-M1 and M1-M2, there was a decrease in the injured condition in pronation and an increase in supination. For the complete lesion group (Group 2), in which the ligaments between C1-C2, C1-M2, C1-M1, and C2-M2 were injured, these distances increased in injured condition both in pronation and supination, as expected. Regarding the behavior of distances C2-M1 and M1-M2, the same behavior pattern was observed as in partial injuries. Conclusion: The cadaveric biomechanical model for Lisfranc joint complex injuries developed in this study simulates the mechanism of clinical stress of the lesion and the most common type of lesion, exhibits reliable and measurable distances, and allows lesion treatment without compromise, being, possibly, an excellent method for comparing tarsometatarsal ligament injury fixation methods.