Is an x-ray necessary for a jammed 5th toe if there is tenderness over the dip joint but not over the pip joint?

Probally not: Toes are always getting bumped and banged and even with breaks there usually justed taped to stabilize them.

X-rays : Could be helpful in making a correct diagnosis and giving you an idea how long it will take to heal and stop hurting.

X-ray : It's always a good idea to get an x-ray to see if fracture is present. If no fracture or closed fracture then tape it to the next toe.