Hybrid user interfaces are commonly discussed in the context of integrating conventional displays into Mixed Reality environments, as well as multi-modality and cross-device interaction. We believe that the consideration of these overarching categories does not suffice to inform the development of these interfaces in very distinct application domains, such as medicine. Instead, we argue that the medical domain comprises of various further aspects that influence the design of hybrid user interfaces. With this work, we want to discuss additional facets that emerge from the specific constraints and challenges of this particular field. To do this, we first introduce three selected research projects, in which we have been involved, showcasing the range of possible tasks and application areas in the context of medicine. As a result, we identify and discuss the following facets: Physical Location, Visualization Placement, Display Capabilities, Interaction Style, Enhancement Target, and Task Concurrency.