To that end, the replacement ligament L might comprise: 1. ligament or tendon or other tissue harvested from the patient's own tissue (known as autograft tissue); or 2. ligament or tendon or other tissue harvested from another human donor (known as allograft tissue); or 3. ligament or tendon or other tissue harvested from an animal source (know as xenograft tissue); or 4. ligament or tendon or oth