Idiopathic scoliosis is a tri-dimensional deformation of the spine of unknown causes, impacting 2 to 3% of the population. It's a chronic pathology starting during childhood or adolescence and it is associated to long term physical and psychological prejudices for the patient, leading to important healthcare costs for the system. The weight of these consequences is linked to the early diagnostic of the pathology and to the subsequent treatment. Therefore, the early screening of AIS is of major importance. In France, the actual screening technique is clinical (Adam's test), it's a technique reserved to personnel of the medical field and with an imperfect sensibility (71-84% depending on the literature). The final goal of our study is to develop a non-ionizing, automatic evaluation tool of the idiopathic scoliosis, that would allow an accurate screening and if possible to evaluate its severity. The preliminary work conducted with this goal is presented in this paper. After a first literature review concerning the idiopathic scoliosis, the depth camera Microsoft Kinect V2 is used to generate a tridimensional point cloud of the back's surface of the patient. This point cloud is computed with the objective of quantifying an asymmetry of the patient's back, indicator of the spine's deformation in the axial plan, a specificity of the scoliosis. The two main axes of work were about the guarantee of the data's reproducibility and the choice of a pertinent parameter for the back's surface asymmetry, based on clinical and physio-pathological hypotheses and on the available literature data. The outcome of this preliminary work is a novelty surface parameter acquired in a patient-related coordinate system, with the goal to maximize its reproducibility. The first results on a few healthy patients and a scoliotic patient were encouraging. This work will obviously need to be followed by a validation study on a larger cohort of healthy and scoliotic patient. A key objective in recommending assistive technologies is to promote personal independence, social participation and life-building.