I strongly suggest that you see a board certified orthopedic surgeon for a second opinion. To my knowledge, torn cruciate ligament injuries in dogs are not something that will heal without surgical intervention. Oh, the symptoms may improve, but the dog will immediately start to get severe arthritis. I am posting some links below for you to review:
ACVS - Cranial Cruciate Ligament Disease Yorkie Haven Rescue - Cranial Cruciate Ligament Tear Info 01 Ruptured Anterior (Cranial) Cruciate Ligament - VeterinaryPartner.com - a VIN company! http://groups.yahoo.com/group/jrwardnewsletter/join? Ruptured Anterior Cruciate Ligament (ACL) in Dogs