Hi Paul,
There's some info on
http://hometown.aol.com/amcahome/polyneur.htmIt does mention that the condition is often misdiagnosed but I would imagine HD could easily be ruled out through x-rays as polyneuropathy is a nerve rather than bone/joint problem.
I don't know if there have ever been any cases in the UK, I am not aware of any.
HTH
Regards
Jacquie (Myatuk Alaskan Malamutes). :)