Page 122 - ShowSight - October 2020
P. 122

                FORM FOLLOWS FUNCTION
  Figure 6. Muscular Attachment of Front Assembly to Body
“THE ARTICULATION OF THE SHOULDER BLADE WITH THE UPPER ARM FORMS THE SHOULDER JOINT.
THIS ‘SPHEROID’ (BALL AND SOCKET) JOINT ALLOWS FOR A VERY WIDE RANGE OF MOTION SO THAT THE DOG CAN CHANGE DIRECTIONS QUICKLY AND EASILY.”
Figure 7. Fore Assembly Attachment
The shoulder blade is attached to the neck (cervical vertebrae) and ribs (thorax) by muscles beneath the blade (dorsally) on the flat side of the shoul- der blade—and above from the spine of the shoulder blade (see figure 6). Muscle “A” rotates the shoulder blade, “B” extends the forearm and “C” straightens the elbow.
This muscular attachment of the fore assembly to the body not only attaches the two areas one to the other, it also supports the weight of the trunk and its muscle groups, and serves to advance and retract the leg as well as move the neck. You need not learn all of the names and functions of each of the muscles in the canine body, but you do need to have an under- standing that it is muscles that move the bones. The upper, larger edge of the shoulder blade is placed slightly below the spines of the spinal (vertebral) column (see Figure 7). The shoulder blade has no joint connection with the upper chest and spine, but lies between and is fused to flat muscle attached at the 3rd–9th vertebrae. Ideally, the highest part of the shoulder blade lies just below the level of the first through fourth vertebrae with the spine of the shoulder blade (scapula) pointing to the highest part of the blade.
In the majority of breeds, the upper arm is the largest bone in the fore assembly and, even though most breed standards call for an upper arm length as long as the shoulder blade, it is, for most breeds, actually longer than the shoulder blade. This is because the “point of the shoulder” usually referred to in measuring body length is actually the upper end of the upper arm (humerus) (see Figure 8).
The articulation of the shoulder blade with the upper arm forms the shoulder joint. This “spheroid” (ball and socket) joint allows for a very wide range of motion so that the dog can change directions quickly and easily. It is at this shoulder joint that the leverage is applied by the force of the muscles to change the position of the bones, allowing movement of the leg. The properly articulated bones of the shoulder and upper arm also serve to increase the area for the muscles to attach the entire front assembly to the trunk of the dog; and the more fit the muscles, the stronger and more flexible the dog is, which allows for more supple movement (see Figure 6).
This article will be continued in the next issue.
As always, if you have any comments or questions or would like to schedule a seminar, contact me via email—jimanie@welshcorgi.com
 Figure 8. Shoulder Joint
 120 | SHOWSIGHT MAGAZINE, OCTOBER 2020
      





















































































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