Elongate implant structures can be introduced into an airway system to a target airway axial region, often to apply lateral bending and/or compression forces against the lung tissue from within the airways for an extended period of time. Structures or features of the implants may inhibit tissue reactions that might otherwise allow portions of the device to eventually traverse through the wall of the airway. The devices may enhance the area bearing laterally on the tissue of a surrounding airway lumen wall. Embodiments may have features which increase the device friction with the airway to allow the device to grip the surrounding airway as the device is deployed. An appropriate adhesive may be introduced around the device in the lung. Hydrophilic material may inhibit biofilm formation, or features which induce some tissue ingrowth (stimulation of tissue growth) may enhance implanted device supported.