The angry nurse kept pulling in his elbow and knees. He wouldn't just lay down and comply with detainment.

Then they discovered his (first?) weapon and they took it away from him.

But then he was still trying to hold himself up like a four legged table, pulling hard to keep his elbows in and his knees folded.

It was reasonable for law enforcement to anticipate his continued resistance was to not give up his prerogative to draw out a 2nd weapon.