I'm a physical therapist. It was actually a torn meniscus and the rehab process that brought me into the profession in the first place!

A torn meniscus is not necessarily a big deal. Small tears are better treated without surgery, and people often can return to vigorous activity within a couple months. Larger tears require 1 of 3 surgical options, all of which are arthroscopic. In order of recovery time: 1) Meniscectomy. They remove it entirely. You're back within 2-3 weeks, but probably will develop arthritis in the future. 2) Debriedment. They just trim out the torn parts. Back in a month. 3) Repair. They sew it back together, but then you have to stay off it entirely for 6 weeks, and then rehab.

Good luck.