Connection rods for use in spinal fixation systems in conjunction with interbody fusion; contoured connection rods with tabbed ends, rod introducers, rod length measurement templates and other hardware for use in an image guided midline surgery for lumbar interbody fusion that uses a minimal access computerized spinal surgical technique for placement of posterior spinal screws and hardware that is tissue sparing and allows for the placement of spinal screws via computer guidance followed by additional hardware as required resulting in less surgical site morbidity and faster patient recovery