Why is conformation
important to those of us who are dedicated to the working
ability of the German shepherd dog? Why is the USA Sieger
Show an integral part of our program to develop and
maintain the working attributes of our breed? There
is no answer more articulate than this reprint from
Schutzhund USA’s Jan/Feb ’92 issue by the
head of USA Breed Advisory Committee.
When many people think of a good working dog, they
think of a specimen with stamina, high energy, strength
and power. Although these are qualities rooted in the
mind of a good GSD, too often we forget that the full
expression of these attributes depends on the physical
package in which it is wrapped. A car may have a finely-tuned
engine, but if the tires are flat and the alignment
is off, gas mileage will be greatly reduced. In the
same way a dog with good working drives but improper
structure cannot take advantage of it’s hardware
to perform to it’ s fullest potential.
What is “Proper” Structure?
Simply stated, proper structure is the anatomical design
that offers the least resistance to movement. In other
words, certain physical advantages help one dog perform
a task using less ‘Gas’ than other dogs
not so well endowed. These anatomical features are described
in detail by judges during conformation shows and breed
surveys. However, it is important to know not only what
good conformation is, but also why it is advantageous
to a working dog. To understand the why’s of conformation,
we must apply scientific concepts (especially physics
and kinetics) to dog movement. There isn’t room
enough in this article to discuss every aspect of GSD
structure, but we can look at one aspect (rear conformation)
in depth as an example of how proper structure affects
the working dog.
The Science of Rear Conformation
Forward movement in dogs begins in the rear. The strength
of that movement or drive depends on how the rear assembly
is designed. In GSD’s rear assembly is defined
in terms of angulation, meaning the relatives position
of the bones to each other during a certain phase of
movement. When we stack a dog for show in the typical
“Shepherd stance” we present the angulation
of that dog during two phases of movement.
The leg retracted under the body shows the angulation
at the moment when the effective push forward begins.
The extended leg shows the position of the bones when
rear drive is about to end and the leg is lifted off
the ground in what is called follow through. The ideal
angles called for in most standards refer to those in
the retracted leg, and they are as follows:
If that is true, why then do judges look at the dog
from the ‘wrong’ side, that of the extended
let? A correct dog with it’s leg in the extended
position and hock perpendicular to the ground will show
two sets of parallel lines: the axis of the pelvic bone
(croup) parallels to the tibia (stifle), and the axis
of the femur (thigh) parallels to the metatarsus (hock).
These parallel lines are intimately related to angulation.
Parallelism is retained through the entire range of
motion of the rear leg during the trot; when the leg
reaches the position under the body where it is bearing
the most weight and begins to push forward (see figure
2), the bones are at right angles to each other as called
for the standard. The retracted leg can be stacked adopting
different angles, but the hock can fall perpendicular
to the ground in only one position. So, judges look
at the side that will not ‘lie’ to check
for parallelism, croup position, turn of stifle and
plumb lines. But is it really true that efficient rear
drive depends on the prescribed augulation? Or is it
just a capricious decistion of those who control the
evolution of the breed?
Ideal Angulation and Strength
Bones don’t move by themselves. The position of
bones is important because it directly influences muscle
action. Muscle length and angle of Insertion are primary
factors for efficiency. Long muscles are better suited
for speed, while short muscles provide greater strength.
In GSD’s, muscles are neither very long (as in
Bulldogs), thus they provide a good balance between
speed and strength. The angle of insertion of the muscle
into the skeletal frame is most favorable when the line
passing through the muscle and tendon is at a right
angle to the bone upon which is acting. For example,
one of the main muscles contributing to rear drive is
the gastrocnemius, as shown in the following illustration:
It attahes to the top of the hock through the Achilles
tendon. It’s principle function is to open the
lower angle of the rear leg (formed by stifle and hock)
thus producing a rear kick and forward thrust. In a
dog with correct angulation, the angle formed by the
tendon and hock at the time when the muscle contraction
is peaking, is an optimale 90 degrees. But what would
happen if we increase rear angulation? Most often, angulation
is increased when the tibia and fibula (stifle bones)
are lengthened. When the stifle becomes longer, the
dog’s weight automatically overcomes the strength
of the ligaments on all the rear joints. This is due
to simple application of physical principals of leverage.
The angle would be more easily bent using the long
lever shown on the left than with the short lever shown
on the right. Most overangulated dogs have stifles that
are much longer than their femurs, therefore the longer
‘lever’ of the stifle overpowers the natural
strength of the joints, angulation is increased (becomes
more acute), and the dog ‘sinks’ under his
own weight.
To open up the angle, the muscle is forced to use greater
strength.
The lengthening of the stifle changes the center of
gravity of the dog, sliding it backwards and placing
greater stress on the lumbar area which is not built
to cope with it. It also lengthens the Achilles tendon,
reduces the power of the muscle, and above all, disrupts
the parallelism (see figure 6)
The Importance of Parallel Lines
Parallel lines offer the greatest advantage in rotational
force.
For the two people trying to rotate the bars in the
above illustration, the greatest rotational force is
achieved when the lines in which they are moving are
parallel. Any deviation from the parallel directions
of push results in wasted energy. When the stifle and
croup are parallel to each other, full force is transmitted
by the rotation femur, through the croup, and into the
back, thus propelling the dog forward without energy.
Parallel lines also ensure that the plumb lines running
through the hocks and femurs are both perpendicular
to the ground, offering great stability and correct
center of gravity (compare figures 3 and 6). The interaction
of parallel lines, correct angulation, good position
and length of croup, and strong, well-toned muscles
creates a very effective rear assembly capable of delivering
the most power in exchange for the least possible energy
consumption.
The Future of Our Breed
Other aspects of proper conformation similarly affect
the working ability of the dog, especially those related
to the front assembly. Although many GSD fanciers remain
unaware of this intimate connection, working dogs enthusiasts
are nevertheless well-served by maintaining proper conformation
through continued judging of their dogs agains the breed
standard. Events such as the Sieger Show are much more
than a simple ‘beauty contest, ‘they are
an important part of maintaining workability in our
dogs.
A good GSD is a miracle of careful design and genetic
engineering -- body and mind working together as a well-oiled
machine. We have many events to help us evaluate mental
qualities. Let’s protect the heritage that has
been entrusted to us as breeders and competitors and
pursue more eagerly the second half of the equation
– conformation – demanding fullness of quality
and a total dog.
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