What broke in my suspension?

Hey FABO, I was pulling my dart out of the driveway yesterday and heard "POP" right before the driver's side took a nosedive into the pavement. I got out and saw that it was resting on the lower bump stop; nothing actually hit the ground. Jacking the car on the pavement, I noticed the perch, that the adjustment bolt touches, was turned nearly vertical! So I removed the torsion bar, to release the tension, and moved the perch back down to the adjustment bolt with the bolt nearly threaded out. I lowered the car and it promptly rested on the lower bump stop again. I got it back into my driveway but it's raining today so I will not get to really assess what broke.

My rudimentary assessment is that there is no resistance for the torsion to prop up the weight of the car. So I am thinking that either the hex socket in the transmission cross member broke free and is spinning; unlikely as this is a CA with little rust. Or something broke in the LCA that does not resist the perch from rotating. I have yet to tear apart a LCA so I am unfamiliar with their construction; FSM isn't much help either. These are PST 1.03" bars and the "L" is on the driver side.

Does any of this sound familiar or can someone recommend what to look for first?