Posterior Judgement

by Lisa Dubé Forman

Fanciers and Judges make a great to-do over the dog’s hindquarters but can they really recognize a sound, strong pelvic girdle and pelvic limb construction? Although breed blueprints revolve around specialization demanding differing angles to include descriptive terms, such as sweep of stifle or great length from hip to hock, unimpaired hindquarters construction is the same, no matter the breed.

First, we start with the basic technicalities to differentiate the thoracic from the pelvic limbs. The pelvic limbs are fused and jointed to the vertebral column, whereas the thoracic limbs are connected by muscle and ligaments, that is to say not bone to bone. The pelvic limbs are heavily muscled, longer and more angular than the thoracic limbs as they are responsible for propulsion. Pelvic limb movements surge or throw body weight forward and the thoracic limbs catch and support this weight no matter what the stride and gait. Please note that stride and gait are not the same but more on this in another essay. One more fundamental is that the arrangement of the pelvis girdle and rump muscles enables the simultaneous extension of the hip, stifle and hock. I will delve into regional musculature in another series.

Moving on, the strength of the pelvis girdle and limbs, length and angularity of its bones and quality of muscling, in almost all cases, ultimately determines successful running speed. Because the dog species are carnivores, Mother Nature constructed him for running. Obviously today, as humans have intervened in evolution and created significant variations in the species, therefore functions, some breeds have greatly limited running abilities, i.e., today’s Bulldog or Pekingese. Despite this, even the Bulldog’s hind end should be strong and muscular.

Many fanciers have taken great liberty, far too much liberty, redesigning the hind limbs. Frequently we see improperly angled croups, and over- and under-angulated hindquarters to name but a few. A quick refresher on determining ‘hindquarter angulation’ involves two methods. Hindquarter angulation includes determining the angle of the pelvis from the horizontal (pelvic slope), see my previous essay Stern Warning. This is determined by estimating a straight line from the forward part of the ilium to and through the ischial tuberosity; the other method is estimating the stifle joint angle which is the angle created at the intersection of the lines running centerline through the femur and the tibia.

The average, desirable stifle joint angulation for functioning dogs is 90-110 degrees. Simplifying ‘overangulated’ is when the angles of the femur and/or the tibia themselves are set too sloping. The angle created by the femur articulating from the hip bone to the stifle (knee joint) and through the axis of the tibia is narrow, more closed, less than 90 degrees. In contrast, open angles might be more than 110 degrees where such straightened femur and tibia do not generate power and drive. Also, in many cases we see irregular length of bones in the hind limbs where the tibia bone, which articulates with and is connected to both the stifle and the tarsal joint (hock) and is one of the major weight bearing bones in the hindquarters, is too long and steeply sloped.

This results in drawing out the distal tibia, tarsal joint and rear feet dramatically, placing them well behind the ‘seat bones,’ effectively weakening the rear assembly’s capacity, thrust, and strength.

I repeatedly emphasize that the angle of the pelvis is very influential. Since the pelvic angle affects the width of the stifle, a faulty slope limits the area for muscle attachment and the dog may have narrow thigh muscles. This is because many important muscles and tendons originate, are housed and attached on the femur, one of the strongest and longest bones in the rear. Weak and narrow thigh muscles do not show promise of speed or power.

If the dog has a weak or poorly constructed posterior, the dog is handicapped. There are some who reproduce haphazardly, perhaps breeding to a dog that frequently wins in the conformation show ring without much thought to the pertinent details I discussed. Some casually believe that if a trend, such as over-angulated hindquarters, results in accumulating more ‘wins,’ then so be it, if that is what they have to do to win. In these cases, I logically question their posterior judgement.

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