A couple of weeks ago, a gentleman brought his mare to me, looking for a jumping saddle. I took a template and asked (as I always do) if the horse was having soundness or saddle fit issues. The gent responded that he'd just had his vet do a full work-up, complete with x-rays, and the mare was declared sound. But there was this one small problem with saddle fit: whenever he rode the horse, she'd go exactly four steps, and then try to buck.
I evaluated the saddle the gent had been using, and didn't see any major red flags. I felt the mare's back and found no soreness, swelling, lumps, bumps or thickening; there was no major asymmetry, and the mare walked and trotted quite sound. He longed her before we started trying saddles, and she went around fairly willingly, though - to my eye - there was something just a tiny bit off. Exactly what, I couldn't say, but something about her body use and the way she held herself didn't feel right.
The gent was on a somewhat limited budget, so we tried all the saddles in the shop that were in his price range that looked even remotely likely to fit. Every time, the result was the same: the mare pinned her ears and wrung her tail while being tacked up, and after the gent mounted, she'd go exactly four steps, drop her head and try to buck. Saddle after saddle after saddle. We even tried a saddle that was way beyond the gent's price range, but that had the fitting options the mare required ... and got the same result. We tried a Mattes pad, a Skito pad, a synthetic sheepskin pad, a girth with elastic, a girth with no elastic - all with the same result.
Finally I told him, "You know, I hate to tell you this, but I really don't think this is an issue with saddle fit. I'm not a vet, but I think there's something else going on here."
He wasn't too happy to hear that - understandable, given that he'd just spend a considerable amount of money having his mare vetted. He asked me what else could be causing the reaction we were seeing.
I replied, "Again, I'm not a vet, and you should discuss this with your vet, but it could be any number of things. It could be ulcers; it could be painful ovaries or some chiropractic issue. It might be neurological, it might be Lyme disease, or it could be a nutritional issue - vitamin B or vitamin E/selenium deficiency. I really don't know - but I am willing to say that I don't believe saddle fit is the problem here."
"Why not?" he asked.
"Because we're seeing the exact same reaction every time, no matter which saddle or pad or girth we're using. If it was a saddle fit issue, we'd likely be seeing a different reaction when we alleviated the problem.
"Did your vet do any blood work?" I asked him.
"Just a Coggins," he answered.
"I'd recommend that you ask your vet about doing some diagnostics to find out what's causing this. I think you need to deal with the underlying cause before we can consider finding a saddle."
So yes, there are times when saddle fit isn't going to be the answer. Some problems may appear to be caused by an ill-fitting saddle, but their underlying cause might be illness or injury, problems with shoeing or dentistry, bad training or riding, or inherent conformation problems that cause unsoundness. And sometimes it's sort of a "chicken or the egg" situation: did saddle fit cause the soundness/behavioral/training issue, or did an underlying problem with soundness, behavior or training end up making the saddle fit badly?
Saddle fit's always a good place to start. But if the fitter doesn't think the saddle is the issue, or if you're getting the same reaction consistently, no matter what saddle you try, talk with your vet about which diagnostics would be most appropriate. Finding and treating the cause rather than worrying about the symptom is always the best route.
And by the way, if I ever find out what was causing the problem with that mare, I'll be sure to post it here.