Up to now, only one experimental study reported the mechanical properties of the global costo-vertebral (CV) and costo-transverse (CT) articulations. However, from this study, it was not possible to determine the specific contribution of each component of these articulations. Therefore, to complete the understanding of these articulations, more data were collected. Twelve different functional units (FU) composed of 2 adjacent vertebrae (T₁-T₂, T₅-T₆ and T₉-T₁₀) and one corresponding rib were tested. A steel rod was inserted in the costal neck and used to give the following loads to the FU: normal to CT facet, cranial and caudal, as well as torsional loadings around the rod. Each FU was firstly loaded with most of ligaments intact, then with the CT joint ligaments removed (costal neck and head ligaments intact) and finally with only the costal head ligaments. For normal loads, results showed that CT joint ligaments represent 52% of the rigidity for FU T₅-T₆. The torsional rigidity was found to be almost the same for FU T₉-T₁₀ nevertheless of the ligaments tested (4.95 Nm/rad ± 0.71 Nm/rad). Other results showed that the FU T₅-T₆ is the stiffest, followed by FU T₉-T₁₀ and FU T₁-T₂, which is in concordance with results published by Schultz et al.. Small dispersion of the results was observed in spite of the small amount of specimen tested. These preliminary results were used to calculate CV and CT mechanical properties needed for finite element modelling of these articulations. Simulations were performed with the model and adequation was found with experimental results.