The body emits heat and each part of the body gives off its own individual temperature, for example the muscles and tendons, etc. This gives us a thermal pattern unique to the horse.
For pure clinical scans it's always best to have a full scan when the horse is fit and well and then issues occurring later can be more easily compared.
We base this pattern on symmetry and where we find the pattern is out of symmetry it suggests there may be an issue. Cold thermography spots are as important as hot thermography spots.
In the picture we can clearly see the near fore is colder than the other legs and it would appear the horse is reluctant to put weight through the leg. We compare the rest of the scans to narrow the area of concern down for your vet, thus eliminating or reducing nerve blocking, which are both expensive and uncomfortable for your horse.