Evaluation of an improved suspension system concept for surgical luminaires

Surgeons have indicated ergonomic problems with the surgical luminaire, which have been observed to occur during repositioning. The possibility of singularity, within the movement space of the translational subsystem of the current double-arm suspension systems, is confirmed to be the cause of these problems. In this study, a redesign of the translational subsystem is compared to the conventional translational subsystem. A user experiment with 14 participants is setup to compare the redesigned and alternative system. The experiment is performed outside the operating room (OR), with one setup that can be altered between two designs; an uncoupled state with the kinematics of the conventional subsystem, and a coupled state with the redesigned kinematics. Work cost, duration, and jerk cost are compared, as well as NASA TLX score. The work cost of a movement in the conventional uncoupled state is confirmed to depend on the spatial orientation of the mechanism, which is not the case in the new coupled state. Due to these different kinetics, the movement patterns with the coupled mechanism are more consistent between participants, the duration of movements is shorter, less problems occur, and participants are able to better control the movements as demonstrated by lower jerk costs. This result validates the redesign and confirms the hypothesis that a translational subsystem without the possibility of singularity within its movement space will improve luminaire repositioning. The conceptual design can now be used as base for a clinically usable design.