A method for measuring the displacements of a vertebral column, a vertebra of the column including a location marker attached thereto and providing a location system with an orientation of the location marker, the method including: a detection of an initial orientation of the location marker associated with a vertebra, a determination of an initial orientation of a vertebral plane parallel to at least one end plate of the vertebra, and a calculation of a geometric transformation associated with the vertebra correlating the initial orientation of the vertebral plane with the initial orientation of the location marker, a detection of the current orientation of the location marker, and a calculation of the current orientation of the vertebral plane of the vertebra from the current orientation of the location marker and the geometrical transformation associated with the vertebra.