A head-mounted wearable device utilizes electronics placed in one or more of a left temple or a right temple. The temples are joined to a front frame using hinges. The hinges provide passageways, slots, or other openings to permit passage of a flexible printed circuit (FPC) within an open core of the hinge. The FPC allows communication between the left temple and the right temple. During motion of the hinge, the FPC may twist such that the ends within the hinge are rotated relative to one another while remaining substantially parallel to one another. The overall length of the FPC passing through the hinge remains substantially unchanged between the hinge being open or closed. The FPC remains protected within the hinge and is minimally displaced, preventing the introduction of a crease in the FPC at a hinge line.