Thanks for choosing health care magic for posting your query.
From the description that you have given, you have a meniscal tear and the same can cause locking your knee and then the pain can be severe. Arthroscopy
should be done in your case. It is a very safe procedure and generally they dont remove the whole of the cartilage
. Instead they remove only a segment of it which can cause problem. Mostly there are no short term or long term side effects of arthroscopy.
Hope I am able to solve your concerns.
If you need any further help in detail, I will be more than happy to help you.
Wish you good health.
Dr. Pooja Reddy MD