knee replacement help

oneday

hi all
i have a friend who is going to have a knee replacement and hopefully under epidural due to other medical issues that may make a full general anaestihic a problem.
Has anyone on here had a knee replacement with an epidural if they also have problems with their spine, think its spinal stenosis. Friend concerned that because of back problem an epidural may be ruled out but then worried about a general due to other medical problems.
thanks for any help peeps.
Just realised am in wrong forum!