Apparatuses and systems can mitigate the ingress of debris such as small foreign particles or fluids passing into a joint of an electronic device. Some aspects of the systems prevent particles from passing between a flexible cable and a mandrel surface used to limit bending of the cable. Other aspects provide particle relief features including gaps, grooves, or reduced-size sections of the mandrel so that particles can pass into them and thereby cause no damage or pass out of the electronic device. Another aspect provides a protective layer configured to limit pressure applied to the cable by particles or other contaminants. These apparatuses and systems can improve the life and durability of the mandrel and cable, thereby improving the reliability of operating the electronic device.