I have osperisis arthritis in my knee im over weight trying to lose it but my knee clicks cracks why is my cartlidge damaged i don't have pain all time?

Had an MRI?: There r 2 types of cartilages in the knee. The articular ; the meniscus, also called cartilages. A torn meniscus can b associated with episodic symptoms of catching, clicking ; catching as well as giving way. Usually due 2 injury. The articular cart .Is the gliding surfaces. Can b from injury or wear and tear. Usually more constantly symptomatic. An ortho xame is in order 4 u.