Without manipulation or some type of surgery it doesn't appear to be possible to regrow cartilage.
However, you can take action to reduce joint pain which may be helpful to you. Foods rich in vitamin C (broccoli, peppers, strawberries, oranges, and leafy greens), and vitamin A (carrots, sweet potato, leafy greens), plant-based protein (almonds, hemp seeds, beans, lentils, other nuts and seeds), and anti-inflammatory omega-3s (fish, walnuts, hemp and chia seeds) and certain oils (cold pressed coconut, olive, almond) are all great additions to a joint-friendly diet.
In addition, three supplements that you may want to asks your Dr. about are:
MSM (Methyl Sulphonyl Methane) is a flexible bond between proteins for your hair, skin, joints, tendons and cartilage.
Glucosamine occurs naturally in the body and helps maintain connective tissues and cartilage.
Chondroitin is also found naturally in your joints where it helps your body attract fluid into the cartilage.