Most cartilage injuries are due to impact or twisting movements, and are more common in contact sports. Anyone can fall, though, including runners and cyclists. Blows and falls can cause cartilage tears. These can hurt, cause clicking noises, and may make your knee lock on occasions. M.D. Small tears in a meniscus may heal with rest.
Menisci have a variable blood supply, and in some cases healing can take months.
Larger tears and complete tears are more difficult. Cartilage injuries need expert care. In many cases, a conservative approach with rest and a change of activity works well. The change may have to be permanent, though. Putting stress on a damaged cartilage can only lead to more problems.