Some patients often ask, “Doctor, do I need surgery for a 2nd degree meniscus injury? Will conservative treatment work? To answer this question, first of all, we should be clear: there are four types of MRI signals of the meniscus: 1, no abnormalities. 2, Ⅰ degree signal: thin linear signal, less than the joint surface, is normal meniscus has mild degeneration (is the sense of aging). 3, Ⅱ degree signal: there is a regular thicker status quo signal, less than the joint surface, is the meniscus has moderate degeneration performance, generally age 20 years old and above normal people often have, not abnormal. 4, Ⅲ degree signal: irregular signal to the joint surface, is torn, need surgery.