I know of two people (grooming customers) who didn't do the surgery on dogs with ACL problems. One lady had a GSD, she found out about these supplements http://www.springtimeinc.com/ and had great success with them. I haven't researched it much myself but she told me often they have to have surgery on both knees because they mess up the other one taking weight off the injured one after surgery. The dog was still sore sometimes but overall she did great and could walk fine. Another grooming customer told me their golden retriever had torn her acl so I told her about the supplements as well. She was older (10ish?) when it happened so the vet had recommended not to do surgery. She used the supplements and after a year it was amazing the vet checked it again and said she didn't even need surgery at all...she was still a little sensitive about that leg but she walked fine, when it first happened she would not even put weight on it and lost all muscle tone.