Microfracture: Producing small holes within the bone and bone marrow underneath the damaged cartilage, which stimulates the bone to repair itself (by means of marrow cells), resulting in recently formed cartilage problem. Preceding injury aspects for example preceding meniscus accidents which reduce shock absorption on the cartilage You'll need healthier knees https://www.theorthopaedicandpainpractice.com/what-are-cartilage-lesions/