In vivo thorax 3D modelling from costovertebral joint complex kinematics

The costovertebral joint complex is mechanically involved in both respiratory function and thoracic spine stability. The thorax has been studied for a long time to understand its involvement in the physiological mechanism leading to specific gas exchange. Few studies have focused on costovertebral joint complex kinematics, and most of them focused on experimental in vitro analysis related to loading tests or global thorax and/or lung volume change analysis. There is however a clinical need for new methods allowing to process in vivo clinical data. This paper presents results from in vivo analysis of the costovertebral joint complex kinematics from clinically-available retrospective data.In this study, in vivo spiral computed tomography imaging data were obtained from 8 asymptomatic subjects at three different lung volumes (from total lung capacity to functional residual capacity) calibrated using a classical spirometer. Fusion methods including 3D modelling and kinematic analysis were used to provide 3D costovertebral joint complex visualization for the true ribs (i.e., first seven pairs of ribs).The 3D models of the first seven pairs of costovertebral joint complexes were obtained. A continuous kinematics simulation was interpolated from the three discrete computerized tomography positions. Helical axis representation was also achieved.Preliminary results show that the method leads to meaningful and relevant results for clinical and pedagogical applications. Research in progress compares data from a sample of healthy volunteers with data collected from patients with cystic fibrosis to obtain new insights about the costovertebral joint complex range of motion and helical axis assessment in different pathological conditions.