A medical device system includes: a surgical arm mounting device including a coupler and a surgical arm interface, the coupler including a clamp for a first side rail of an operating table; and a support member including a brace, the brace extending from the coupler at least part way across the width of an operating table. The clamp has a first mechanical state in which the mounting device is fixed to the side rail, a second mechanical state in which the mounting device is translatable along the side rail, and a third mechanical state in which the mounting device is removable from the side rail. The surgical arm interface is configured to receive a mating mounting device interface of a surgical arm.