A lateral fixation assembly engages vertebrae in a spinal column. The lateral fixation assembly includes a housing having a first rod and a second rod supported thereon. The first rod is adapted to be secured to a first vertebra in the spinal column and is fixed in position relative to the housing. The second rod is adapted to be secured to a second vertebra in the spinal column and is movable relative to the housing. Respective pluralities of such first and second rods may be provided. Staples having varying thicknesses may be provided to facilitate the installation of the lateral fixation assembly on the vertebrae in the spinal column. A temporary blocking device can be used to prevent relative movement of the movable rod during the installation of the lateral fixation assembly.
