The analysis of the human body's movement touches many fields of research, because it allows to bring elements of understanding in rehabilitation, in the improvement of sports performances or in the monitoring of muscular fatigue. The capture of the spinal column movement has its importance, particularly for spinal pathologies, such as idiopathic scoliosis in adolescents. The technologies available today to perform spinal motion capture require patient instrumentation and mobilize significant resources, which limits their scope of action. Using the already existing literature, a system based on a depth camera has been developed. It allows to capture the movement of the spine without instrumentation of the patient. The depth camera captures the anatomy of a patient's back as a 3D point cloud at a rate of 30 frames per second. These clouds are then processed to extract the line of the spine. The first results allow to extract information on the curvature of the spine in 3 dimensions over the duration of a forward bending test, where a patient leans forward, trying to touch his feet. Even if the robustness of the proposed solution still needs to be evaluated on a larger population in order to verify its robustness, the monitoring of this information would allow to quantify the quality of the movement to assess for example a level of fatigue.