What are chondral flaps and where are they located? What is grade2 and 3 chondromalcia with unstable chondral flaps on the patella mean?

Articular cartilage. The bearing surface of a joint is made of cartilage. It is white, shiny, and smooth (what you see on the end of a chicken leg). Arthritis is damage to this surface. During knee arthroscopy, damage to this surface is graded (grade 1-4). Grade 2-3 chondral flaps means that there were moderate degenerative changes on the undersurface of your knee cap or patella.
Bad knees. This is a description of x-ray or MRI findings of fairly severe wear and tear of the cartilage on the underside of the patella. (knee cap). Seeing an orthopedic surgeon for arthroscopic debridement may be required. If you don't have insurance, then you need knee sleeves, lots of ice and rest before rehab.