If the pain were just in her foot, I would agree that it isn't sciatica. But since it is radiating from her back, across her butt, and down the back of her leg before residing in her foot, that is exactly the same as when my sciatic nerve was pinched due to a herniated disk in my back. Most of my pain resided in my ankle on my left foot (on the outside right below the knobby bone).

Li10up, I fell right before Christmas (unplowed city streets on my way to a final exam... that was fun!), was sore for a couple of days, then on Christmas day had some pain in my butt that mimicked piriformis issues that I had had before (like was SadieKate mentioned), did some stretches for that and boom.... shooting pain down my leg. My dad had to put a board under my mattress so I could sleep and I cried myself to sleep that night. Spent the next 3 months going to Physical therapy trying to get things under control, had an MRI around Easter. When my doc called, he said the herniated disk was really obvious in my case (ruptured to the side) and that I must be in a ton of pain. He told me that at this point, since medication, rest, and physical therapy hadn't helped that surgery was really the only option left for relief. I was finishing college, so didn't go and see a surgeon until mid-May after I had graduated, but they took one look at my MRIs and my other symptoms and I was scheduled for surgery the next day. So, I was basically in constant pain for about 6 months. My pain was very similar to what you describe, hurt in my but in the piriformis region, down my leg and then resided in my ankle... I really never had much pain (or at least it was eclipsed by other pain) in my back, it was all in my butt, leg and ankle.

The things online that say it usually gets better in a couple of weeks or months is generally if the sciatica is due to muscle spasms and injuries, or very small herniations that can actually be pushed back in with physical therapy. Once you get to severe herniations there really isn't a lot of option for pain relief other than surgery. Like SadieKate said though, you do need to determine where the nerve compression is coming from, if you don't know that you don't know how to treat it. Just given that you fell in a way that was similar to mine (only you fell further) makes me think that there is a chance that it is a disk, and x-rays won't show this, only an MRI or CAT scan. If you look up piriformis stretches online you can see how doctors generally diagnose piriformis syndrome, but I have to warn you, doing these stretches is how I made my disk a lot worse than it was, so you probably shouldn't do these on your own given the amount and length of time you have been in pain.

While surgery is a last resort, it was the best thing I have ever done... I couldn't believe how much better I felt right after I woke up. If you want more details about the surgery, recovery etc., feel free to PM me. I was at the point of just wanting to bend over in the Drs office to have them take care of it immediately, but that still didn't quite prepare me for the reality of being told I was having surgery the next day.

Good Luck!
Ellen