Although the initial symptoms of spondylitis can arise at different spinal levels, specific axial and lateral rigidity always feature the motor functions of the spine. This work is a preliminary attempt to integrate clinical data with a quantitative analysis of the spinal motor performance in order to monitor and quantify the progressive strategies of the disease. To such a purpose, 15 spondylitic patients of various age and different seriousness of the disease have been examined by means of the AUSCAN System while performing simple motor tasks (orthostasis, lateral single-side bending and double-side bending of the trunk). The obtained results concerning the inter-segmental rigidity of the spine point out the presence of two typical motor strategies which are strictly related with the upward or downward features of evolution of this pathology.