A 3-D acquisition device, dedicated to external measurement of a whole human trunk for an application of modelisation before its use in a CAD process, has been specifically developed. This device offers a non-contact, fast and accurate method to give the user reliable data for modelling and reconstruction of anatomical surfaces ; it would represent at the end, after several clinical tests, a fundamental step for the following processings, allowing analysis and evaluation of the scoliotic treatment taking into consideration morphological and clinical internal and external parameters. Several ways of digitisation of human bodies are offered today ; a few of them are accurate enough in one angle of view (for example on the back) but most of these are affected by the difficulty to deal with the time of acquisition for a 360 degrees digitisation. In this last case the relative movement of the patient during the measurement (that could last several seconds) causes errors which spoil the quality and the reliability of further modelling. The paper describes a device able to take the whole trunk of a patient in less than 2 seconds with a standard deviation of 1 mm in safe and comfortable conditions for the patient. Detailed results are displayed.