I attempted to have cryosurgery (freeze-nerving) done on my gelding twice....and it did not work. I have heard many, many surgical nerving stories, ranging from incredibly positive and optimistic to horrifying and fatal for the horse. This is enough for me to consider the procedure a last-ditch option to buy the horse some quality of life before euthanizing it--NOT as a procedure to salvage a riding/competition horse. Too many risk factors, from neuromas, to regrowth of the nerve, to missing abscesses and fractures while they fester for weeks, to complete ddft rupture and collapse of the limb.
Only had experience with one 'navicular' horse that was nerved myself. Nerves grew back, horse was lame again, then they called me as a 'last ditch'. Thankfully they were happy to get boots for the horse, which we padded, including thick 'frog support pads in - the heels were high & contracted, way off the ground - and allowing comfortable exercise along with regular trimming to gradually improve the balance & heel height & use, the horse was able to become comfortable & free moving bare in the paddock. He was also an old boy & wasn't expected to 'go back to work'.