Abstract: An injection instrument that includes a saddle configured to receive a syringe aligned on a saddle axis; a linear member coupled to the saddle at a sliding joint, the linear member having a first end and a second end, the sliding joint allowing relative movement between the linear member and the saddle in a direction aligned with a slide axis, the slide axis parallel with the saddle axis; and a guide member located at the second end, the guide member including an edge spaced apart from the saddle axis by a prescribed distance, the guide member including a tissue contact surface, wherein the tissue contact surface is located on a single side of the saddle axis.