How did your normal vet diagnose the ACL tear? Our normal vet suspected knees, but didn't bother to evaluate further, just sent us to the specialist.
The specialist got on the ground with our dog, laid him on his side, then held the problem back leg in a certain position and put pressure in a specific way on the knee joint. The joint moved = ACL tear. She then tried the other leg and saw small movement = partial tear. From what she said, there is no need for an MRI or any further evaluation. The joint moving in such a way indicates ACL tear.
Did your vet evaluate the knee like this?
Vet pretty much thought it was an ACL tear to start like I said, got down and felt the legs while she was standing, and noticed some swelling in the one knee on inspection. She moved the leg a bit and said she didn't like a certain range of motion. That was about it, but she seemed 100% certain it was an ACL tear and just couldn't really tell if it was partial or full.
Lots of stuff I'm reading today on ACL's do describe the way she's moving and say that their behavior can range from looking slightly limp, where I'd describe her, all the way to not wanting to use the leg at all. So I guess this isn't abnormal with the injury. Just seems strange, but I guess it makes some sense. Rivers played on an ACL tear with a brace and some guys seem to feel extreme pain while others seem to be walking around and you figure it's probably not an ACL until the MRI comes back.