Saddle Fit and Design for the Short Rider

Shorter riders need specific changes in saddle design and fit to accommodate their body types. As obvious as it may seem just shortening the flap will not create a better saddle fit for someone who is of smaller stature. When the knee roll or the leg support of the saddle hits the knee it can turn the leg out from the horse making it difficult to keep the lower and upper inner leg against the horse.
A saddle with a narrower twist is usually the first step in ensuring fit for a shorter rider. The twist is very often misunderstood. Twist is an arbitrary designation what is crucial is the area on the saddle it refers to which must be considered when fitting a saddle.

People often think it is in the crotch area however the twist is actually that part of the saddle that is felt between the riders upper inner thighs. A wide twist under a short rider results in more leg away from the horse and the rider will sit as if on a barrel unable to get her leg on the horse. Women are usually much better off with a narrow twist regardless of their height because of the way their pelvises are shaped.
The twist has nothing to do with the horse. You can have a very narrow twist on a saddle for a very wide horse and vice versa. The riders upper thigh lies against the stirrupbar area which is actually far away from the horse. So the tree width measured at the gullet area of the pommel is for the horse while the twist is for the rider.
A wide seat the widest part in the back of the saddle will give a short rider more comfort. In general women are better off with a wider seat width as a rule because their seat bones are wider apart than mens. A saddle with a half panel instead of a full panel on the underside of the saddle reduces layers and stuffing between the rider and horse. The half panel helps a shortlegged rider get more control with her lower leg and upper inner leg especially when riding horses with wide barrels. 
A saddles seat size also depends on the size of the horse. Being shortlegged doesnt necessarily mean that you need a small seat size. There are small slim women who ride in 18 5inch saddles. Seat