Methods and apparatus for forming one or more trans-sacral axial instrumentation / fusion (TASIF) axial bore through vertebral bodies in general alignment with a visualized, anterior or posterior axial instrumentation / fusion line (AAIFL or PAIFL) in a minimally invasive, low trauma, manner and providing a therapy to the spine employing the axial bore. Anterior or posterior starting positions aligned with the AAIFL or PAIFL are accessed through respective anterior and posterior tracts. Curved or relatively straight anterior and curved posterior TASIF axial bores are formed from the anterior and posterior starting positions. The therapies performed through the TASIF axial bores include discoscopy, full and partial discectomy, vertebroplasty, balloon-assisted vertebroplasty, drug delivery, electrical stimulation and various forms of spinal disc cavity augmentation, spinal disc replacement, fusion of spinal motion segments and implantation of radioactive seeds. Axial spinal implants and bone growth materials can be placed into single or multiple parallel or diverging TASIF axial bores to fuse two or more vertebrae, or distract or shock absorb two or more vertebrae.