An orthopaedic biomechanics project to reinforce mechanics principles

A team of junior and senior students investigated the mechanics of an interlocked IM rod and tibial Sawbone construct associated with increasing cortical comminution as part of research and design course. Comminution of the cortical bone and its concomitant lack of inherent stability have led to the use of interlocking rods to control length and rotation in unstable fracture patterns. The treatment of long bone fractures with an intramedullary rod has become an accepted practice with surgical techniques and implants being refined over the last 70 years. A clinical question - "what is the clinical significance of fracture comminution and post-operative cortical contact?", provides a real-world problem for reinforcing the concepts from mechanics of materials. Cyclic axial loading in a nonfailure mode will give results that can be extrapolated for use during the early phases of fracture care when the stability of the limb is being provided solely by the implant. With the results of the tests, the investigators hope to be able to make recommendations for the clinical application of the implants. Evaluation of project by the faculty and project sponsor involved the ability of the students to use mechanics of materials, articulate the design of experiments, testing, analysis through mapping of student tasks and evidence to the ABET a-k objectives.