In uk,does barristers from both sides on a personnal injury case be in regular contact ?

Barristers talk to each other all the time, though even if they're the best of friends they will never "connive" over a case where they oppose each other. The laws about what can and what cannot be discussed are complex & draconian.

Yes, barristers talk between themselves all the time to try and resolve a case. None of them like to go head to head with each other. Lots of barristers working around the same courts are in fact good friends with each other.

Surely you mean, in UK English at least,
"In the UK, do the barristers from both sides of of a personal injury case have regular contact with each other?"
In answer to your badly constructed question, yes they do.

Actually it is your solicitor who negotiates a settlement before the matter gets to Court sometimes with the advice of a barrister. It can save costs which often bear little relationship to the amount involved but do effect the amount of work put in. They also agree as much as they can before the trial i.e. they may agree medical evidence and your actual loss before they go in to Court and the hearing will concentrate on liability. i.e.
was it the fault of A that B was injured or was B in part or wholly the author of his own misfortune