Question: Pastern proportion - Page 2

Easy one - BC. The standard states that the pastern should be '1/3 of the length of the foreleg' and the standard is the standard, but as with many things that are quantified in dog standards it can sometimes be ambiguous or even unclear as to exactly how you measure; specifically, where do you you measure from and to. For the uninitiated it is important to know that the pastern should be measured from the carpus to the start of the toes - not the end of them. For what its worth my observation is that approximately 25% of the length of the Radius' is a good functional and proportional length for the pastern and in relation to what I said earlier about measuring, I say Radius as opposed to 'arm' or even 'foreleg' because it can be confusing for novices who will nearly always look at the Ulna in making such a determination and the difference is significant.

 Louis  

Just to make sure I understand the correct measurement of the pastern are these the two points where measurement should start and end ?

Which is the correct way to measure the Radius please? 

First sketch is correct - imagine your hand and the fingers are cut off - the leading edge of whats left, the palm, is the end of the pastern. In the second set of radiographs the answer is B. A is pointing to the top of the ulna. The point I make 'in a measuring context'  is of course - what is the definition of 'pastern' and what is the definition of 'foreleg' - in regard to the standard exactly what are you supposed to be measuring to come up with the 1/3 ???


Louis

I might be wrong but I always understood that fore arm is the Radius and fore leg is the (Radius + Pastern + foot pad). But I noticed that you use the term fore leg for fore arm so I am now confused.

Maybe 1/3 rd is true when we ad the pad thickness to the pastern bone, and then compare it to {the distance between elbow joint (where both the Humerus and Radius meet) upto start of pastern}, like in the sketch below. Red/Green= 1/3, What do you say?
Anyhow I think it is too difficlt, rather impossible for a man to measure these distances and proportions physically on a dog.

Forearm is the term used to describe the part that goes from the wrist to the elbow in a human and foreleg is the equivalent for a quadruped. Two rear legs and two fore legs v's two upright legs and two forearms.
The 1/3 is elbow to pastern and as you said it is a visual guide and I suspect it most likely includes the toes. One would normally make a visual assesment using the elbow as a reference point and one could say the variables and finer detail being discussed are semantics but it is interesting if you enjoy the finer detail of these things especially when it comes to measuring.

Louis

Maybe Louis could tell us if he's referring to an Australian version of the Standard.  All the translations
I have to hand  (including an early German one)  neglect to mention the 1/3 measurement;  either that
or I can't see the wood for the trees.  I was thinking this was a little odd, since the '1/3' gets referred
to / used frequently enough, it must come from somewhere.
None of the resources I've looked through (as I told you they are limited 'cos some are still in storage)
discuss it in text, either - although they mostly have descriptions of the bone and the ligaments and the importance of proportion to achieving a correct gait, etc etc.  And they all mention the difference between:

WUSV / FCI   20 degrees
UK   20-23 degrees
USA   25 degrees 'from the vertical'.

I guess the difference evolved from various countries changing the Standard to suit their own dogs.
Or the USA Standard chooses actively to 'do its own thing' re the B to D measurement, in the face of
everyone in Europe thinking it should be B to C. ?

So I measured Taz, instead !  (Why think it impossible to measure ON the dog ?)*
He has this set of measurements:
A to B  21 cm
B to C   7 cm
B to D   8.6 cm

Case closed ? 
L.
*Edited to add:  OK, OK,  I couldn't measure the ANGLE on the dog !!!  Hehehe.

Oh, you could with a little trigonometry, ha ha.

BTW, as the hypotenuse, your B to C measurement should be longer than B to D.

Or, maybe not, because of the toes.