| Idiopathic scoliosis is a complex three-dimensional (3D) deformity of the spine and the rib cage. In the case of a severe spinal curve, patients are generally treated by surgical instrumentation and fusion of the deformed spine segment. In front of significant rib cage deformity (rib hump), thoracoplasty, a cosmetic surgery that consists to resect rib segments, is an option. It is generally accepted that scoliosis progresses by a self-sustained biomechanical cycle due to unbalanced loading of the spine, which alters bone growth. Hence, some authors proposed that rib surgeries (resection, shortening or lengthening) could reestablish the force balance transmitted to the spine, and consequently reverse or slow down scoliotic deformation progression. These innovative surgical concepts were tested in experimental studies on animals and in a few clinical studies. However, these rib surgeries remain empirical procedures for which a large number of variables needs to be controlled. A biomechanical study was achieved in order to clarify the action mechanisms of the rib surgeries and to explore the influence of the surgery parameters.;The present project is a continuation of this study. It encloses two main parts with the first one concerned by the immediate effect of rib surgeries. This part aims at developing a method to examine more thoroughly the influence of the surgery parameters and to identify the parameters maximizing the correction of the scoliotic deformities. The second part of the project aims at developing a biomechanical modeling that will enable to simulate the long-term effect of rib surgeries. Consequently, bone growth and growth modulation by load resulting from the surgery must be represented in the model. (Abstract shortened by UMI.). |
