After many years of treating meniscal tears, doctors have determined who can rehab the injury and who should have surgery. The doctor will look at where the tear is located, the length of the tear, the stability of your knee, and the condition of the other knee structures. Certain conditions must be operated on. For example, tears that are longer than 10 millimeters require surgery.
Most orthopedic doctors are willing to try rehab first. Usually, a program of exercises is prescribed by a physical therapist. If after rehabilitation the knee "locks up," preventing any motion and causing severe pain or swelling, surgery is advised. Likewise, reinjury of the same knee will probably call for surgery.