1. An implantable device system, comprising: a first electrical subsystem that interfaces with tissue; a second electrical subsystem; a connector that connects the first electrical subsystem to the second electrical subsystem; and a guide tube that operates in the following modes: active mode: wherein the guide tube is rigid in the axial direction and facilitates insertion of the first electrical subsystem into tissue; and inactive mode: wherein the guide tube allows the first electrical subsystem to move freely with the tissue; wherein the guide tube comprises at least one spline that is rigid in the axial direction; wherein the entire length of the guide tube is made of a flexible material that is flexible in the radial direction and rigid in the axial direction; wherein the diameter of the guide tube is expandable such that the guide tube transitions between active mode and inactive mode by expanding the diameter of the guide tube and sliding the guide tube over the second electrical subsystem; and wherein, during the transition of the guide tube between active mode and inactive mode, the connector connects the first electrical subsystem to the second electrical subsystem.