Horses occupy a special place in our society. Long since they have turned from livestock to companions and friends and have gained an important place in our hearts.

Both enthusiastic riders and people who are not involved with horses are equally fascinated by their size, beauty and character, and mesmeried by their presence.

Sice early civilization horses represented something special. Often they were consideered to be part of a deity. When galloping across the plains with their manes blowing in the wind, their elegance remidns the ovserver of a lost and forgotten freedom.

In the following pages I would like to elaborate on my views regarding the connection between the saddle and the horse´s anatomy.

It is not a scientific study, but rather a personal opinion which has developed in co-operation with veterinarians, riders and saddle producers over the years.

I. History of the saddle

1. From being a source of meat to becoming a farm animal

Our predecessors of the Stone Age knew the horse not as a riding animal but as a source of food. The hunters of the Ice Age drove herds of horses over vertical cliffs in order to kill them. The cliffs of Solutré in Burgundy in eastern France is well know for showing evidence of just such hunting methods having taken place there approximately 20,000 years ago.

The horses was probably domesticated around 2,700 BC by the Aryans. They were nomadic people who spoke an Indo-Germanic language and inhabited the steppe around the Black and Caspian Sea.

The horse was probably ridden, but riding it played a secondary role to its other uses.

2. Scythians and Sarmatians

The Scythians used a numnah made of felt which was often elaborately embroidered as well as stirrups. The Greeks, Romans and Persians, however, only used a simple saddle pad that they attached to the horses back by way of a girth and a chest strap.

The numnah used by the Scythians did not only serve as decorsation but was used a long marches folded underneath the saddle and provided effective protection. The saddle was made of leather and felt. Two cushions were used, which were well stuffed with deer hair and held together by leather straps or a continuous piece of leather. The cushions were placed on either side of the spine on top of the numnah so that the weight of the rider was distributed onto the back musculature as well as the rib muscles. This construction still corresponds to modern principles for saddling: the saddle must not press on the spine but rather on the sides along its whole length so that the spine itself carries no weight.

The Sarmatians lived to the east of the Scythians. What makes them different to the Scythians is the fact that they had a heavy cavalry. They are credited with being the first to have built a saddle with a wooden frame or tree.

The initial development of the saddle over the course of several thousand years shows us two things: on the one hand we see a sclow progress in technical evolution, and on the other, decisive innovations that have had such a lasting influence on modern saddle constructions that we have to acknowledge the Scythian-Sarmations saddle as the original desing of our modern saddle.

3. then and Now

After these two peoples had laid the foundation for the sport of riding, our modern sport saddle was only developed in the last two centuries, from a wooden crutch, as it were, to a flexible sport seat.

To understand the modern saddle construction as it relates to different riding styles and the resultant behavior of the horse, a basic anatomical knowledge of the horse is required. In the following discussion we will concentrate on three areas: the horse, the rider and the saddle. The object is not to peddle new teachings or doctrines for there is no alternative to the natural anatomy and its biomechanics.

II. The Horse's back

The back of a horses is, apart from the mouth, the most sensitive body part. It is the body part that, by the act of riding, is also the one that is the most used and under constant stress.

The back has a close association with other body parts such as the head and neck, the chest and abdominal wall as well as the shoulder and pelvic limbs.

1. Components of the back

The back is made up of many different tissues that work in close relationship with each other. These different tissues should be discussed separately. Especially in the back, the close interation between the different components like bone, muscle, ligaments, tendons and nerves becomes clear.

2. The bony skeleton

The thoracic/chest- and lumbar spine make up the bony scaffold of the horses back. The thoracic and lumbar spine has virtually no curve, compared to the cervical/neck spine. By virtue of its specific anatomy it allows only very little movement.

The individual vertebrae have a growth plate at their front and back ends which allows growth its longitudinal axis. The vertebrae continue to grow for several years, the last growth plates only close once the horse is approximately six years old. In addition, the dorsal processes of the thoracic spine have their own plates; these only close after the horse is ten years old.

The horse´s spine is like a curved horizontal chain made up the different vertebrae. It consists of 7 cervical/neck vertebgrae, 18 thoracic/chest vertebrae, 6 lumbar vertebrae, 5 sacral/pelvic vertebrae and 18 to 21 tail vertebrae. The horse´s back is a bridge. Because of the horizontal position of the back one should rather speak about a spinal bridge than a spinal column.

Due to the specific construction of the back, it is able to carry large loads without any problems.

Exact measurements of the movement of the spine were first undertaken in Europe by Zschokke. He discribed that the stability of the spine is largely dependent on the dorsal processes and the atteched spinal ligament (ligamentum supraspinale). He measured a lowering of the back of only 4 cm with loads on the back of 50 to 80 kg, provided the dorsal processes were intact. He was also the first person to describe the change in the position of the dorsal processes as it relates to changes in the position of the head and neck.

The thoracic-,lumbar- and sacral vertebrae have dorsally ("going to the top") directed extensions, the so called dorsal or spinal processes. They are titled towards the tail up to the 15th thoracic vertebra. The dorsal process of the 16th thoracic vertebra upright and all from here to the 18th pint towards the head. The first eight true or supporting ribs as well as the last ten respiratory ribs are atteched laterally to the thoracic vertebrae. The ribs are atteched to the sternum via a cartilaginous junction and form the closed rib cage. The rib cage protects the organs within it from injury and in additon gives the support necesaary to carry the horse´s own body weight.

Direction of movement:
According to modern definitions, the spinal column moves in four different ways:

  • a. Dorsoflexion – hollowing the back
  • b. Ventroflexion – arching or making a hump of the back
  • c. Lateroflexion – bending to the side
  • d. Torsion – twisting around its axis

The greatest degree of bending to the side takes place during the walk. The largest up and down bending, however, happens during a trot. At a walk and trot a change in position of four to five centimeters can be measured. At a gallop a change of only three centimeters in measurable.

Luckily, the sternum also allows us to tighten a girth which enables us to ride horses.

3. The back muscles

In simple terms the back musculature can be divided into the actual and connecting back muscles. A further difference exists between the short and long back muscles. A further difference exists between the short and long back muscles.

An important muscle is the long back muscle or musculus longissimus dorsi. This muscle fills the triangle created by the dorsal spinal processes an the lateral spinal processes that is present along the length of the spine. It should completely fill this space and even bulge beyond the spinal processes. Apart from the muscles above the vertebrae, muscles that run under the vertebrae are also needed and should be equally trained.

The muscles that play a role in the support of the neck and trunk can be divided into the upper, middle and lower muscle girths. The upper girth consists of the long neck muscles (splenic and longismus dorsi muscle), the middle part consists of the brachiocephalic and psoas muscle and the lower girth is made up of the straight abdominal muscles.

4. The functions of the back

Long before man discovered that one can use the horse´s back to carry loads, it had to fulfill important bodily functions. It is often assumed, incorrectly, that the back is made for riding. This function is however a secondary function. It has an important role to play in many aspects; here only a few:

a. protection of the spinal cord
b. protection of the heart and lungs
c. attachment and confinement of internal organs
d. free movement of the limbs

The back is without a doubt the pivot of the propulsion system of the horse. So, what happens to the back of a horse when it is ridden and what is important to us when building a saddle?

III The movement

For the horse to engage his hind quarters he must "round" his back. This rounding is also known as bascule. The opposite to rounding would be a slack back or "sway back". Close examination of the spinal column reveals the dorsal spinal processes at the level of the 14th to the 16th thoracic vertebra to stand virtually upright. This is the center of the dorsiflexion of the back and thus also the center of the back´s stability.

Fauques (1982) first described the measurements between the dorsal spinal processes in live, moving horses and the changes in these measurements with different positions of the head. He noted that the distance not only change with the different movements (walk, trot and canter) but also with different positions of the head.

The lowest part of a saddle must lie over the center of maximal stability of the back. The back, even of fully grown horses, will not be able to withstand the incorrect position of the rider´s weight for any lenght of time.

Dupaty de Clam, a musketeer of the French King, wrote in the last chapter of his book on the art of riding in 1769 about the importance of the center of gravity of the rider and the horse and how they affect eacht other:

„According to the principles, which we will allude to, the horse, when standing square, has a center of gravity in which all its strength and all its power is centered. This center has a perpendicular line. The art of riding consists of getting this line to correspond to the center of the rider´s gravity line so that they are in harmony.“

IV The rider

Looking at the spinal column of the rider, nothing more needs to be done but bring the natural biomechanically determined plumb line of the rider in harmony with the plumb line through the horse´s center of gravity.

a. The plumb line of the rider goes from his ear throught his shoulder to his hips and then to his ankle.
b. Prober riding position (straddle seat) means sitting upright, left and right on both pin bones.
c. Sitting upright does not mean pulling the pelvis up, but allowing the forward tilting of the pelvis.
d. Poise and balance means free movement of all joints and a smooth muscular upright seat, bringing the plumb line to its correct position.

It is assumed that the rubbing of the dorsal processes, also know as "kissing spines", is due to the repeatet un-physiological sinking of the back. Poor tensioning of the back musculature as well as the inhibition of head movement by the rider lead to lowered tension in the spinal column and may be part of the cause.

V The Saddle

A saddle is used to make riding an animal more comfortable and safer as well as to protect the back of the animal. A well fitted saddle for both horse and rider will support our riding efforts and it will place the rider there where the horse would place him without a saddle. This position would be rihgt behind the withers.

The saddle must fit the horse perfectly, i.e. it must allow optimal freedom of movement for the shoulder blades, the withers and the rounding of the back.

One of the most important areas of the horse´s back is the withers when designing and manufacturing saddles. This is the area where the saddle is placed and together with the rider brings additional weight onto the back.

Already the horse is carrying 55 per cent of its weight on the front legs and 45 per cent on its hind legs. The plumb line and the center of gravity of the horse lie at the level of the sternum just below the middle of the rump. In addition, the three centimeters thickened back edge of the shoulder blade lies directly underneath the withers. This is important for the saddle maker as this is the area where the shoulder blades move.

Well trained horses have well developed trapezius muscles. These lie directly behind the shoulder and fan upwards towards the long spinal and rib muscles where the fibers intermingle.

The saddle must allow free shoulder action. To do this the panel must open to the sides in front to allow maximum freedom of movement of the shoulder. The shoulder action is often impaired by most saddles because the panel is heavily padded in front causing a narrowing of the gullet. It would be better to change the width of the tree in front and leave the openign of the panel.

Point straps (first girth strap) will increase the tension in the shoulder by tightening and fixing the saddle in the forward part of the saddle tree. By this fixation to the shoulder, muscles will lose their suppleness and because of the intermingling of the back muscle fibers, this tightening may become evident as foar back as the croup. The results can be a "cold back", problems when the horse is asked to collect itself or even when the rider just wants to mount, unwillingness to work, evasion of brush strokes during grooming etc.

The panel (the padded underside of a saddle that comes into contact with the back) must clearly conform to the anatomy of the horse´s back. This is especially true due to the intermingling of the back muscels, which may lead to severe back problems. The ideal panel should overlap the back muscles at the junction between back and rib muscles. A narrow panel will press the long back muscle against the vertebral column and spinal process and push the rib muscles down and away.

You can see that the horse´s elasicity and ground covering stride must not be impaired by the saddle. It must in fact support such movement. This results in imperative rules for designing and making a saddle.

VI Characteristics of saddle design

1. Saddle tree:

The saddle tree has to be flexible lengthwise and crosswise, thereby being able to move with the movement of the horse and rider instead of being a rigid obstruction between the two partners. The modern saddle tree should be adjustable with the ability to be adapted to any changes in the horse´s back.

2. Head Iron:

The head iron above the withers ensures the head´s stability and reaches from the shoulder blade downwards and backwards. The lower ends open towards the bottom.

3. Panels:

a. The panel should be smooth (not lumpy) and elastic.
b. There should be no edges catching on the horse´s back.
c. It should be open in the front
d. The angle of the panel should conform to the angle of the horse´s back.

4. Panel distance and width:

a. The panels should run parallel with at least 5-6 cm distance between them.
b. The panels should be wide enough to span across the back muscles and the juncion between the back and the rib muscles.

5. Flocking material:

The flocking in the panels made of synthetic fiber should be soft and flexible even when exposed to moisture. It should compact and adapt itself to the horse´s back but remain elastic.

6. Girth system:

The girthing begins with the first point of contact under the stirrup bar, not at the end points of the front arch where the front achr width´s measured. Its form corresponds to the natural depth of the horses girth area.

7. Air circulation

The saddle construction support air circulation of the horse´s back thereby preventing hot spots and heat accumulation.

8. Materials:

Carefully selected materials make the Sommer saddle a natural product that becomes mor beautiful with age. Our leathers are carefully selected and tanned for us throughout the world and have to pass strict quality control inspections before being used.

9. Variability:

The fit as well as the front arch width ca be changed at any time.

VII The End

By choosing a saddle, a rider takes one of the most important decisions for a good partnership with his horse.

Happiness on earth is to found on a horse´s back. What is happiness for humans, however, means torture for some horses.

With this short presentation we hope to have given you a little insight into our philosophy. For more than forty years, perfection and harmonious interaction from all over the world have come together in the family business Sommer and its specialists.