Building and tracking root shapes

International audienceAn algorithm aiming at robust and simultaneous registrations of a sequence of 3D shapes was recently presented in IEEE T-BME 55(5) by Jacq et al. Along the way, this algorithm has to carry out an implicit representation of their common root shape. A particular emphasis was put on the median consensus shape, a specific type of root shape. Unlike this previous work, mainly focussing on the algorithm foundations while dealing with very specific applications examples, this paper attempts to show the versatility of the root shape concept through a set a three problems involving a wider scope of application. The first problem copes with the design of prosthetic cortical plates for the hip joint. It shows how an explicit reconstruction of the root shape, coming with its consensus map, could bring out an intermediary anatomical support from which could be made pragmatic choices performing a tradeoff between morphological, surgical, and production considerations. The second problem addresses in vivo real-time shoulder biomechanics through a miniature 3D-video-camera. This new protocol implicitly operates through root shape tracking of the content of virtual spotlights. It is shown that the current medical-oriented protocol, while operating within expert offices through low-cost equipments, could challenge high-end professional equipments despite some limitations of the 3D-video-cameras currently available. The last problem deals with respiratory motions. This is an auxiliary measurement required by some medical imaging systems that can be handled as a basic application case of the former new protocol