A horizontal-transvertebral curvilinear nail-screw (HTCN) including a body portion having a first end and a second end, wherein the first end is opposed to the second end; and a head at the first end of the body portion, wherein the body portion has a predetermined curvilinear shape and includes a pointed tip at the second end of the body portion, and a method of surgically implanting universal horizontal-transvertebral curvilinear nail-screws (HTCN) into a plurality of adjacent vertebrae.