Right.
Sorry for your bad luck with the scope
Unplug the scope from outlet
First i would check all the board inter connects leads front panel contacts PSU connectors etc etc.
Those can get dislodged by shock quite commonly.
Next check for any physical damage on the board (cracks chips etc) Twist boards carefully to reveal any hidden cracking (use care and not too much force)
After that do careful physical study of the structure paying attention of stress points (Especially case screw areas where the shock will have transferred to internal components.)
If all these steps show now damage you should progress to checking the voltages.
Plug the device and turn it on (do not do this unless you are aware of the dangers of high voltage and are comfortable progressing. Use care be aware
Use manual to find the voltage test points.
Go through full voltage testing of all boards
If all voltages are fine you should move to troubleshooting actual CRT what i believe is most likely culprit (do not skip the other steps as they will rule out other possible malfunctions)
Unplug power (not just turn it off)
Word of warning CRT's are dangerous best of times and study carefully what you can and cannot do with CRT's
Again do not progress unless you are sure you know what you are doing.
Make physical study of the CRT observe any outward physical damage do careful study with magnifying class or other suitable optical assist.
Again pay particular attention to the stress points (where case makes contact with the CRT and ESPECIALLY the neck that is the weakest point in CRT.
make sure neck board is attached well (again remember safety and checking the board is well seated can be done with plastic tool rather than touching it) use care
!
Now all these steps might show no issue but as the reason of the malfunction was caused by concussive force it is possible if not likely CRT is internally broken
To verify this you will need some specialist equipment and a specialist.
Do not fool around with CRT's with power on or fiddle with the nipple
and i am not talking about the good kind.
Good luck keep us posted how you progress