What's the worst physical pain you've ever experienced? For me, it was testicular torsion.

I once did an unarmed combat course with an army commando unit. There is one certain way to disable a man and we became very good at blocking those kicks. Yet every once in a while a boot got through and you went DOWN. But no matter how hard that boot hit you were expected to be back on the mat in time to take your turn again.

It may not have been the worst pain I ever experienced, but fifty years later I can still remember it. :)

I was drafted into the army in the 70's during the Viet Nam conflict. Two weeks before my deployment, I broke 3 vertebrae in my lower back. Needless to say, I didn't go anywhere for 6 months. 6 weeks in bed and 5 months of rehab to learn to walk again. That was THE most painful experience in my life.

Sciatic nerve pain down my right leg. Epidures was the only help after two years had a back surgery done and doctor screwed up now I have incontinence and can barely walk

I had an anal exploratory that went wrong and tore inside my anal passage.  There was no medicine that overcame that pain. On top of which it sent my pelvis and whole bottom half into chronic spasm. I suffer myofasicial and joint pain all of the time, my neck gets stuck, knees, sacroiliac joint, hands, lower back, shoulders, but for me nothing has topped this.