Developing a Synthetic Distal Tibiofibular Syndesmosis for the Advancement of Orthopaedic Research
Ankle fractures are common injuries that often have a less than ideal prognosis. Surgical techniques to realign displaced bone fragment have become an increasingly prevalent treatment option for many types of severe ankle fractures. However, the incidence of posttraumatic osteoarthritis suggests that research is still needed in fixation techniques. While the tibia is often the model of choice to analyze fracture treatment options ex vivo, it is not the only consideration in ankle fractures; the fibula, ligaments, and interosseous membrane all play vital roles in the stability of an ankle joint. Thus, there is a need to consider fracture treatment techniques on the entire distal tibiofibular syndesmosis. Considering the limitations of cadaveric specimens, composite bones have been created in an attempt to adequately model the mechanical properties of real systems in orthopaedic studies. Previous validation studies have suggested that artificial tibiae mimic natural human tibiae fairly well. This project aims to extend the validation to synthetic fibulas and ligaments. Quasi-static loading tests were conducted to determine the stiffness of the aforementioned components and compare them to human values. A suitable surrogate ligament was identified, and the best methods to attach the ligament to the bone was determined by testing the fixation strength of different adhesives. An artificial distal tibia-fibula system was assembled, with the ligaments holding the bones together, and was tested under quasi-static loading conditions to again measure the construct stiffness. This model has the potential to enhance orthopaedic research and assist surgeons in implementing proper fracture fixation techniques.