A torn meniscus can heal itself if the tear is small and located on the outer portion of the meniscus, where the tissue has a strong blood supply, according to the American Academy of Orthopaedic Surgeons. A longitudinal tear is one type of self-healing tear.
When the knee is stable and symptoms dissipate, surgery is usually unnecessary. However, a tear in the inner portion of the meniscus, which lacks a blood supply, typically cannot heal itself. Without nutrients from the blood, the torn pieces cannot grow back together, explains the American Academy of Orthopaedic Surgeons. Surgeons generally trim the damaged cartilage, in a procedure called a meniscectomy, or repair the meniscus by stitching the torn pieces of tissue together.