Hi!
The 737 has "conventional" controls, (not FBW), so you don't really need a Flight Controls synoptic, even though the 737NG and the 757/767 have it. Moving all three controls through their maximum range lets you know that:
1) No controls jam
2) Both controls, Captain and F/O, do the same thing.
If you have a look at FCOM Normal Procedures, in the Before Taxi flow you will check the Flight Controls as indicated here:
The 737 even has manual reversion, meaning you can fly the aircraft like if it where a Cessna (mechanical linkage) in case of complete hydraulic failure. The MD-80 is an interesting case, it's controlled via tabs that deflect in the opposite direction. So during a controls check in an MD-80 you're just moving the tabs, if the aileron itself is blocked you won't notice. uring the exterior walkaround you make sure that all flight controls are not jammed.
I believe all FBW aircraft have a flight controls synoptic so you can see where the controls are during the check. On the ground, the FBW logic is usually "direct". As we know, in a FBW aircraft the pilot can input a forward force on the column but then the elevator might go down or not, hahaha
Interestingly enough, there was a similar question today in AVSIM here.