title: Design of a lifelong Harrington rod.
abstract: Harrington rods are now well accepted as surgical implants for the correction of scoliosis and in general have proven to be effective in this role. However a number of the rods have been observed to break. The purpose of this note is to outline a simple approach to the redesign of rods which will significantly reduce the incidence of broken rods. By means of a straight-forward stress analysis the propensity to fail of an existing rod is evaluated and two new designs proposed which offer a considerably improved resistance to failure during a patient's lifetime.
mesh_terms: D001696:Biomechanical Phenomena; D005069:Evaluation Studies as Topic; D006801:Humans; D019736:Prostheses and Implants / Q000295:instrumentation*; D011474:Prosthesis Design; D012600:Scoliosis / Q000601:surgery*; D013314:Stress, Mechanical