Your surgeon advised against an operation then ? Sounds to me like a bit of NHS cost cutting.
I read an article in one the national newspapers a few months ago about the NHS cutting back on these operations saying that they class them as "non-essential". It was written by a leading orthopaedic surgeon who disagrees with this policy and says that patients that have conditions like osteoarthritis of the knee would regard an arthroscopy as an "essential" operation because it makes them so more mobile afterwards and reduces the pain and discomfort. This surgeon went on to say that if the NHS thinks it's saving money by reducing these sort of operations, then they should think again. Sustained lack of mobility causes a whole host of other conditions like weight gain, heart disease, diabetes etc.. which is going to cost the NHS a lot more money in the long run. But that's typical of the NHS and this government - short term gains and no thought for the long term future.
My surgeon was very keen to do my arthroscopy - when I saw him for the first time I got the impression he was the "roll sleeves up and get stuck in" type of guy. Just what I'd hoped as I didn't want to go down the steroid injection route. That doesn't cure the problem - just masks the symptoms.
I had my left knee arthroscopy last November. I'd been suffering pain for some months and was finding walking very difficult - especially going up and down stairs. I had an MRI scan which revealed osteoarthritis and two meniscus cartilage tears as well. I was told this was probably a result of an Achilles Tendon rupture that I suffered back in 2011. (three months in plaster and hopping around on crutches - not recommended !!)
My surgeon warned me that there was a small chance that I might not see any improvement. Also the nurses gave me chapter and verse on pain relief after the operation. However, I couldn't have asked for a better outcome. No pain after the operation - not even an ache or twinge. Knee joint was very stiff and initially I was using two crutches to help walk around. That reduced to one crutch after about 3 or 4 days and exactly a week after the operation I walked up to my local pub and back, (albeit slowly), with no crutches - a distance of about half a mile. I still had to use crutches to get up and down stairs for a few weeks. A month after the operation I was out on my bicycle and did a 9 mile ride with no problems at all - in fact my knee felt better for it.
The secret is physiotherapy - lots of it. I was given loads of exercises to do. OK they are boring and monotonous, but stick with them, do more if you can, and you feel the benefit. The more exercises you do, the less stiff your knee becomes, and the less stiff it is, the more you can exercise.. and so on...
It's now about 8 months since I had my op and I can honestly say that it feels like I never had any knee problems at all. Just very occasionally I get a tiny twinge if I twist my knee into certain positions - but it's nothing really. I've been told not to do any activities like jogging or racquet sports which put pressure on the knee joint. The cartilage is still worn and you have take care not to make it worse. Cycling is an excellent exercise - it puts virtually no "impact pressure" on the cartilage and knee joint, but strengthens the upper leg muscles. The stronger these are, the less pressure you place on your knee.
I'll admit not everyone that has this operation will be as lucky as I was - there will be some that will only get partial relief and may require pain relief after the operation. But I would strongly recommend it. The worse that can happen is that you are no better off, but there is every chance you will see some improvement.