I've been battling PF for the past 2 years. I was the the Pediotrist probably 10 times last year for checks, cortisone shots, shoe insert fittings, followups, etc. I finally had a good cortisone shot that kept for a bit. Until the last 3 weeks. It seems to have worn off and now I have another appointment on Monday to see if there is any alternative treatment. I've read about two different treatments if your case is as bad as mine.
One is called ESWT- Extracorporeal Shockwave Therapy http://en.wikipedia.org/wiki/Extracorporeal_shockwave_therapy
The other is PRP - Platelet Rich Plasma http://en.wikipedia.org/wiki/Platelet-rich_plasma
Both are not covered by my insurance, but in reviewing these treatments, it seems that they work better than the cortisone shots and are more permanent, just not justified by a long enough patient trials. The out of pocket was quoted to me at about $500 for these treatments, but for me that seems worth it to be able to sleep without a night splint and be in pain in the mornings and evenings.
Hope this helps.