Medical device designs for enteral nutrition that inhibit the relative motion of one device member to another device member are herein disclosed. The gastric and/or intestinal feeding tube shaft is disposed of teeth, furrows, ridges, indentions, tabs, or corrugations that operate with an external retaining member. Alternative embodiments utilize an external retaining member with a collet fitting that applies pressure against the gastric and/or intestinal feeding tube shaft. The assemblies prevent the relative motion of the internal retention member relative to the external retaining member and assist in maintaining the internal retention member against the gastric wall.
