I had a radical prostatectomy five years ago and was told by the surgeon that there was a 70% chance that nerves would be severed during the operation and that I would no longer be able to achieve an erection. This proved to be the case and since then I have tried all of the medications available, ranging from Viagra, Cialis through to the injections of the penis with a drug whose name I have forgotten, without success. This latter method, may I add, gave me pain without gain and I only managed to achieve a painful semi erection with which I was unable to engage in the sexual act. In spite of this, I still felt aroused sometimes and experimented with self induced pleasure initially and was able to achieve a climax all be it in feeling only. Once I had established that this was possible I moved on to having my wife involved and from there it was a logical progression to use a latex penis for her so that we could both achieve satisfaction from the act of lovemaking.
I post this to encourage other men who have had radical prostatectomy. Don't give up. Anything is possible if you have the will.