The Forequarters In Relation To The Hindquarters
With sportive greetings John Lijffijt (SV) Holland.
(This article has been published with the kind permission of the author).
In the time before the technological development, which made it possible, to understand more about the movement of dogs one believed that the forequarters were mainly used for carrying the body and supporting the body after a jump was made. It was believed that the propulsion only came from the hindquarters, the hindquarters was seen as the engine for movement. The research of Miss R.P. Elliot and Dr. C.M. Brown with the help of cine radiographs and the use of pressure plates has proven that for the propulsion of movement 40% comes from the forequarters. To get all the 40% of the forequarters and all the 60% of the hindquarters to make a 100% useful propulsion, the dog has to be build as a perfect trotter with an optimum technique of trotting and be in good health and condition. From its origin the dog is a trotter, and this is what the GSD should be too. Other breeds have been developed for purposes other than trotting, and that is why they show a different way of movement, also with different body shapes more suitable for their tasks.
A trotter is slightly elongated. The ideal trotter measurements are the height of withers in relation to the body length as 1:1,1 (a 1,15), a length of leg in relation to the depth of chest as nearly 1:1 (GSD 53/54% -.47/46%) and a shoulder angulation of 30 degrees towards the vertical. This shoulder angulation is measured over the shoulder ledge while the described 45 degrees from the Breed Standard for the GSD is measured from the bow joint (the joint between shoulder and upper-arm) towards the highest point of the shoulder a little behind the neck called the withers. This type of measurement made it possible for us to accept an angulation between shoulder and upper-arm of 90 degrees. When using the measurement over the shoulder ledge, the desirable angulation between shoulder and upper-arm is 105 (a. 110) degrees. The bone length of shoulder in relation to the bone length of upper-arm has to be 1:1,1 (a 1,15). The croup has to be angled towards the horizontal in an angulation of 30 degrees. The hereby desired angulation between pelvis and thighbone is about 150 degrees. This is for the most optimum propulsion from the hindquarter. The described 23 degrees angulation of the croup in the Breed Standard is to ensure the there is no further angulation of the croup over the 30 degrees angle as we have now seen for some time.
More important than the exact angulations in degrees is the balance in angulations towards each other. For example the angulations of the hindquarters have to appear to match the angulations in the forequarters.
The importance of the angulation of the croup has to do with the resolve forces in the horizontal direction of movement and the vertical direction of propulsion which has to be transported through the spine over the body in the forward direction of movement. It is known by the theoretical rules of mechanical engineering that the transportation of forces by such angulations as described before, give the most optimum use of these forces with a minimum of loss in directions which do not help forward moving. For the technique of trotting a good physical and mental condition is needed. Especially for the overreaching trotting style of the GSD, a perfect coordination is needed together with a good health and a strongly muscled body.
For a sufficient way of trotting it is important that the legs of the forequarters give a positive contribution to propulsion after they have passed the centre line through the middle of the shoulder and the foot in its back movement until the moment that the toes leave the ground (at the bottom of the centre line the force is zero). Also the legs of the hindquarters only give a positive contribution to propulsion after they have passed the centre line through the hip joint and the foot in its back movement until the moment that the toes leave the ground (also here at the bottom of the centre line the force is zero). The reach of fore- and hindquarter legs is a contribution to the pace length and floating movements during the so-called floating trot. It also makes the centre of gravity move in a more horizontal way, which gives a positive contribution to the endurance of the dog. That is why the firm horizontal back line during movement, is described in the Breed Standard of the GSD. Because of the also desired strong propulsion from the hindquarters which includes a force in a somewhat upwards direction, it is not possible to get a completely horizontal back line without any up- and downwards movement. Also during trotting a dog uses the principle of bouncing (suspension). Hereby the dog uses the absorption of energy, for example in the tendons of the middle forefoot when touching the ground, and giving back this energy to the muscles when making the next pace. A too far-reaching and thereby too early ground contact of the feet, too far in front of the described centre line, has a negative influence (brake force), on the propulsion and thereby on the movement. The relative speed of the foot in relation to the ground has to be zero at the moment of contact, to avoid stamping. By speed increasing during trotting the dog will try to reduce the oscillation of the center of gravity which is caused by the diagonal movement of trotting, by bringing the legs on a single line under the body; the so-called single tracking. This also is a positive contribution to endurance.
It is a fact that nature always tries to compensate short-comings, and a dog is no exception to this. When we see a dog that has not got the desired forequarters as described before, but has the almost perfect hindquarters in movement, we will notice that in the forehand the dog will make compensation to the correct method of trotting to get the best performance out of his good hindquarters. For example, a dog with a steep upper-arm, but with the correct hindquarters, will exhibit the hackneyed method of moving the forehand to create sufficient space for the good drive from the hindquarters.
To understand short-comings, and to recognize the compensations required in movement, and to trace that back to what causes it, is of the most importance to judges and breeders., because they have to evaluate the positive and negative aspects of the individual dog with regards to the breed as a whole. It should also be understood that the individual exhibitor at our dog shows can improve his knowledge about these things by reading or asking (for example the judge he showed his dog to), and thereby get more understanding for the places or qualifications he got.