Veterinary questions? Ask a Vet for Answers ASAP
Since this has been going in for awhile, it is unlikely that this is a fracture but probably involves the ACL or a ligament that will require surgery. If this has gotten worse since the incident, this may have been a partial tear that has now. Become a total tear that will require treatment.
You will have to consult with your veterinarian for the diagnostics to determine the cause and appropriate treatment.
Does that make sense to you, Lorna?