For torn cartilage time and space is by far the best healer. (Had torn
cartilage in my knee due to injury that repaired itself though several years
later had to have the knee replaced.)
If you wish try and hurry the process along, you might try glucosamine and chondroitin.
They are available everywhere from Amazon to Costco to your local drug
store. These items (generally sold as a single supplement) gave me
arthritis/cartilage relief for many years when I was an avid walker.