They also have her leaned against the concrete pillar. The metal object falls once she starts moving. Perhaps she has some leg brace system to prop her up (FDR style).
But look at the faces on the agents and medical people. It seems like another day at the office for them.
The press was kept in a ‘holding pen’ according to one reporter. There were also reports her staff was attempting to ‘round up’ video.
Seems to me that they’re trained and skilled in handling any situation professionally and without allowing emotions (e.g. shock,anxiety) to interfere with the “mission”.