I’d agree that an end neuroma presents a challenging problem.
I have some experience of submuscular or interosseous implantation with varied results. ALternatives include centro-central neurorrhaphy, an end to side neurorrhaphy or a long to relocate the regenerating stump.
Lately there has been increasing attention upon targeted muscle reinnervation (TMR), particularly in the context of an end neuroma within an amputation stump.
Nerve capping is an old technique which showed some promise before falling out of favour. It seems to be seeing a re-emergence with novel materials that may avoid some of the historical problems with the technique. I’m looking forward to the results of the Protect Neuro trial, having used the device in select cases.