Private health who wins?.

I had a double keyhole knee op in April 2008 and at the time I remember phoning your help line team to ask if it were normal to be in so much pain post op, the person I talked to got the wrong end of the stick and asked when I was going to have the OP so I told them I already had it, there reply was I shouldn’t have had it as NICE had put out a new recommendation a month or so earlier stating that keyhole surgery for OA is not to be done unless the knee is locking up or collapses as the results wern't good.
Now the thing is I was never told I had OA in my knees before the OP only afterwards and that was two months post OP, I was told I had a lot of debris in the joints once I’d had an MRI but that was it, I was also told in writing pre OP that there was an 80% chance of some improvement with a 3-5% of things getting worse I never asked what about the other 15-17%!.
Anyway this was all done privately and I just wonder if I have been operated on not for my benefit but for that of the surgeons bank account??, my reasoning is if you Google patellofemoral arthritis there are a few medical reports stating the same thing NICE said and that is the results from surgery aren’t very good for this type of OA sometimes when like now I am in great pain I start to wonder if I haven’t been slightly stitched up?.