If this is the first time and you put it back in place now, you should put ice packs on the knee for 20 minutes every 4 hours for these first 2 days. Elevate the knee to help any swelling go away. Taking anti inflammatory medication. I suggest wearing a brace, preferably a knee neoprene sleeve with no pressure over the patella (a hole over the patella) for 2-3weeks, and as soon as you are painless beginning doing exercises to strengthen the inner side of the quad. Some people need surgery to keep the kneecap from subluxing. While you are recovering from your injury you will need to change your sport or activity to one that will not make your condition worse. For example, you may need to bicycle instead of run.
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