Biomechanical analysis of distraction forces on the posterior meniscal roots to optimize early rehabilitation protocols

• Published in: Orthopaedic journal of sports medicine 2020-09, Vol.8 (9_suppl7)
• Main Authors: Ellermann, Sophia, Kittl, Christoph, Frank, Andre, Wermers, Jens, Glasbrenner, Johannes, Briese, Thorben, Raschke, Michael J., Herbort, Mirco, Herbst, Elmar
• Format: Article
• Language: English
• Subjects: Knee; Orthopedics; Sports medicine
• ISSN: 2325-9671; 2325-9671
• DOI: 10.1177/2325967120S00517

Introduction: The aim of this study was to investigate the distraction forces of the medial and lateral posterior meniscal roots after repair (PMMR, PLMR) at different degrees of flexion and axial load. Hypotheses: It was hypothesized that with increasing axial load and flexion angle, the distraction forces on the meniscal roots increase continuously. Methods: Eight fresh-frozen human cadaveric knees were axially loaded in a custom made kinematics rigs with 0 N, 200 N and 400 N throughout a continuous flexion-extension cycle (0°-90°). The distraction forces acting on the PMMR and PLMR were determined in three scenarios: 1) native knee joint, 2) after bilateral detachment of the posterior meniscal roots and following root repair, 3) after resection of the anterior cruciate ligament (ACL). To measure the distraction forces, the FiberWire No. 2 (Arthrex, Inc.) sutures used for the root repairs were shuttled transtibially through a 2.4 mm bone tunnel and tied over a force sensor mounted on the anterior tibia with a pretension of 2 N. Statistical analysis was performed using a repeated- measures ANOVA with a post-hoc Bonferroni correction (p < 0.05). Results: Overall, the different investigated knee states as well as the degree of flexion showed a significant effect on the distraction forces on the posterior meniscal roots (p 0.05). With axial loading of 200 N and 400 N, the distraction forces on the PLMR were significantly higher at flexion angles between 15° and 90° compared to full extension (p