Intravascular devices, systems, and methods are disclosed. In some embodiments, a guidewire system for treating a patient includes an internal sensor mount having a body and a first cutout extending through a wall of the body; a core wire secured to the internal sensor mount; a sensor assembly for detecting a physiological characteristic of a patient secured to the internal sensor mount; an external housing disposed about the internal sensor mount and including an opening in communication with the cutout of the internal sensor mount; a proximal flexible member secured to at least one of the internal sensor mount and the external housing; a first distal flexible member secured to at least one of the internal sensor mount and the external housing; and at least one conductor electrically coupled to the sensor assembly and extending proximally beyond the internal sensor mount through the proximal flexible member.