Recently, I have had a lot of questions about saddles bridging and I have seen a lot of discussion about it on the COTH forums. There are many different thoughts and theories about the causes; what is considered bridging and what the resultant damage may be.
The most basic definition of bridging is when the saddle only makes contact on two points. Those points would be at the front and back of the saddle, leaving a big space in the middle where there is no pressure, like a bridge, hence the term bridging. There are many degrees of bridging. Sometimes you will notice a large lack of contact and other times there may be the slightest bit of daylight or lightness under the center of the panel. This is determined by “static” fit; fit that is assessed while the horse is standing still, not actively moving. “Active” fit, conversely, is when the fit is assessed while the horse is moving and engaged.
Bridging can be caused by too narrow a tree. The saddle, when too narrow, will sit up on the horse, not making enough panel contact. If one were to try a wider tree, the saddle, if the right shape, would allow for a more uniform contact. If the saddle is too “A” shaped, on a horse that may need an upside down “U” shape or hoop tree, again, the saddle will perch and likely bridge. Picture trying to put a clothespin on a round watermelon! Bridging can cause concentrated pressure on the contact points, thus making for a potentially sore horse.
Another cause of bridging might be too straight of a tree or panel configuration for a horse that has a scooped topline or even a swayback. Although there are trees or saddles that have more curve built into them longitudinally, it is very hard to have no bridging on a horse with a pronounced swayback.
How much bridging is acceptable? This is where much of the controversy is. Many say that a little bit or lightness in static fit it is okay because one expects the horse to use their abdominals and bring up their back. If the horse does bring up its back, then theoretically, it needs a place to bring it and should not be restricted. The other side of the coin is that some feel that the fit should be soft and uniform front to back to disperse pressure uniformly.
Identifying bridging is easy if there is gaping space but not as easy when there is a subtle amount of space. Generally, we suggest girthing up the saddle and trying to feel uniformity or a slight lightness under the center, but feeling the panel front to back. Actively riding and making note of how one’s horse responds is also helpful. It is said that a horse’s gait shouldn’t change more than ten percent from the unsaddled free gaits, (but of course, that also depends on the rider’s ability).
Some identify bridging by looking at patterns on a saddle pad, assuming that dark marks at the front and back indicate heavier pressure. Others rely on sweat marks or dry spots on a horse’s back. Again, different fitters have different theories on these indications and those same indicators can be the result of other issues.
Slight bridging, if not caused by too narrow a saddle can be addressed, depending on the degree, with correction pads, panel options such as K panels, dropped panels, or perhaps, upswept panels. These fixes are not for every bridging situation and should be evaluated by a person qualified to make those recommendations.
The bottom line is that even panel contact or light contact in the center is ideal if the horse is able to move freely and bring its back up. Yet, there are some solutions if the bridging is minor due to conformation issues. Talking to someone that has knowledge in this area and making note of anecdotal evidence makes their job easier if they are not hands on!