Trauma – Direct injury to the knee joint, which includes forceful twisting or bending, may result in cartilage damage. Such injuries are widespread in touch sports or accidents. Past injury elements for instance earlier meniscus injuries which decrease shock absorption within the cartilage Articular cartilage lesions don't often induce symptoms. https://www.theorthopaedicandpainpractice.com/what-are-cartilage-lesions/