post surgery crack

Hey there, thought I'd start a new thread for this one.

I've had my meniscus trimmed and the bakers cyst on the inside of my knee decompressed 3 months ago.

The problem is that now every so often I have a massive crack when I try to straighten my leg, it only happens every so often, but it is a VERY loud crack.

will this dissappear with strengthening or is it an abnormality of this type of surgery and should I be worried?

any help would be greatly appreciated.

kind regards
alex