Hi - I was playing around with some photography of my horses back, and I palpated to locate the LS joint and put a smidge of cream on it and then took an overhead photo to draw a triangle for the loin span. I wonder if the forward point of my triangle is in the right place? What are should the accurate point be?
That's a good photo, Apples. The point of the triangle closest to the horse's head is supposed to lie upon the dorsal process of the last thoracic vertebra. This is not a very easy point to palpate; you can approximately locate it by feeling for the last pair of ribs. You can feel the ribs upward to a certain point, but then they become thickly covered with the horse's back muscles. So from the last point you can feel on either rib, you'll have to extrapolate the remaining distance to the midline.
Sometimes also there is a little more prominence to the dorsal process of the last thoracic vertebra; but not always.
The base-line of the triangle is supposed to go through the lumbo-sacral joint, which is what you have marked with the glob of white cream.
Alternatively, however, you can also put the base-line through the tubera sacrale (the peaks of croup). This is useful as telling you how far ahead of the peaks of croup the L-S joint may lie: the farther ahead the better.
When you mark the triangle with the apex on the dorsal process of the last thoracic vertebra, and the base going through the L-S joint, the triangle will designate the loin span area. -- Dr. Deb
I'm confused about the position of the L-S joint to the peaks of the croup...you want the L-S joint far ahead of the peaks of the croup? The "further ahead the better?" Why was I understanding the opposite in that you want the L-S joint very near to the peaks of the croup?
I've been understanding this incorrectly then. Just want to make sure I am getting it right now. Thanks!
Yeah me too. I thought the peak of the croup being located further behind the L-S joint made for weakness, while the closer the croups peak was to the L-S the stronger it made the entire coupling...Confused...
The only other thing I thought I might be doing is misreading and what Dr. Deb is actually saying is that the farther forward the LS joint the better, not necessarily in relation to the peak of the croup?
I'm thinking it would be very interesting to use the anticlinal vertibra as the forward point. Then triangulate the rear portion of the spinal limb and compare the relationship. Then it would be cool to do the same on the front spinal limb to see if it yields any consistant ratios. This could be the key to defining back types.