This sounds exactly what I had last year!!
Get onto Kim ASAP and do loads of clam/ glute work!!
How it gets better soon!
You've diagnosed him from 'I felt something in my knee' ?
You could be charging a grand an hour for this sort of service Bray
haha - I had the same pain when 'walking downstairs/ down hill'. I'm not saying what it is (even though I kind of did) just thought he might want to know how I got mine sorted.
Doing extra glute stuff isn't bad for you in any case - take it or leave it....
PS - you can transfer the monies to me later ;)