The Choreography of Care: An Ethnographic Study of Human-Robot Collaboration in Makoplasty Surgeries

Human-Robot Collaboration (HRC) in surgery is rarely a straightforward interaction between one human and one robot. In joint replacement surgeries performed with the Mako robot (Makoplasty), the robotic arm enhances surgical precision while also affecting how collaboration unfolds in the operating theater. Utilizing over 80 hours of hospital-based fieldwork, including observations of 15 Makoplasty surgeries and 10 interviews, we examine how the Mako robot shapes surgical HRC. We demonstrate how surgical teams coordinate via tacit cues, negotiated boundaries, and adaptive role shifts across phases of operation. Through vignettes, we highlight the pivotal role of supporting actors, such as nurses and robotic specialists, in maintaining flow and reveal how responsibility is distributed temporally among actors depending on task demands. We argue that surgical HRC is best understood as a multi-actor choreography rather than a surgeon-robot dyad, offering design implications for co-located surgical HRC systems that support distributed collaboration.