With acute facet joint arthropathy the main symptoms is raging sciatica. Back pain is usually minimal and totally overshadowed by what is going on in the leg.
Conversely, the main feature of sub-acute arthropathy is a very painful area in the side of the back that your hand keeps going to for comfort. There may be radiating pain into the butt, around the flank and front of abdomen (if higher lumbar facets are involved), or down the leg. Typically, the sciatic pain is deep and gnawing, like a toothache in the leg.
With chronic facet arthropathy, the pain in the back is more stubborn and low grade, which typically craves pummelling (people get their knuckles or fist in to get relief). The familiar leg pain mainly comes on with prolonged sitting, such as on a long car trip.
See the 3-part facet joint arthropthy discussion here.
Lumbar Facet Joints: The Prima Donnas of Back Pain