Why is my knee making a nasty crunching noise.?

While you may have inherited the family tendency to wear out knee joints, like as not it's more because you were born to a very physically active family who participates in things that are simply hard on the knees. In other words, it may not be a genetic problem, but an activity problem. Yes, all those activities you mention are hard on knees. Chondromalasia patella means you are wearing out the cartilage pad that lies between the kneecap and the bones of your leg. You are wearing out your shock absorber, that's what you are doing. Surgical realignment of the bones may help for a while, but it's not going to let you keep pounding your knees with abandon- if that's what you were hoping. And when you do finish wearing out the padding, the options will be to replace the knee or suffer. They haven't come up with a replacement shock absorber yet, they can't really repair it permanently, and those knee replacements are not exactly like the ones nature provided you. At this point, you should return to see the doctor. And you should give consideration to changing some of your sports activities to those more knee friendly kinds. You may still be able to play hockey, at least the friendly sort of match- but not competitively. At 14, that might sound harsh but as you pointed out, you only have one set of knees. Wearing them out this young means a long life of knee troubles, and there could end up being a lot more limitations than just not playing hockey or track. Just because you inherited the weak family knees does not mean you have to join the family collection of knee scars and troubles. It just means you will need to make some hard choices perhaps.