Accident that caused knee injury. This!

Hi I met with an accident on April 2016 . My leg was injured . My knee was injured badly . I didn't take the injury seriously . The pain kept on relapsing . With each passing day the pain kept increasing . I did with a mri on January 2017 . The doctor who diagnosed my condition said there is nothing wrong with my knees . Its only the bone that has slipped a little sidewords due to impact . He advised me a few vmo exercises and recommended for a physiotherapy . After doing all these the pain still persists . I often experience a lot of pain below my knees and there would be lot of swelling of my foot some times it becomes so heavy that i find very difficult to walk . Please suggest me the proper method of treatment . I would be greatful . It has crossed 2 years and i am going into depression because of this Thanks