The Up And Down Of It – Shoulder Angle/Humerus Bone – Part 2

In part one I talked about the difference between shoulder slope and shoulder angle.  The important parts to remember are;

  • We want the horse’s shoulder slope to largely land between 45-55 degrees, the lower end for a Dressage horse and the upper end for a jumper, outside that range at either end is doable but comes with potential issues
  •  Anything less than 90 degrees is a closed shoulder angle and significantly affects potential stride length, and for most horses it should be a deal breaker
  •  A horse standing with its front legs too far under its body or too far out in front of its body will artificially change the shoulder angle

The above addresses the swing potential of the front leg, but there’s something else in the front end that determines all the rest, specifically the style of the horse’s movement; daisy cutter or high knee action and everything in between.  Even the horse’s front end lateral movement comes from this: the length and orientation to the horizon of the humerus bone.   The humerus is attached to the scapula at the point of shoulder by a ball and socket joint giving the humerus bone forward and back motion as well as side to side motion.  At the other end the humerus joins the radius-ulna (forearm) bone creating the elbow joint.

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Here are the basic rules about the humerus bone:

  • The longer the humerus bone the more scope to the horse’s movement, forward and back as well as laterally – a long humerus bone must be at least 50% the length of the scapula
  • The shorter the humerus bone the more choppy the horse’s movement – a short humerus bone would be less than 50% the length of the scapula
  • The steeper (vertical) the humerus bone the higher the horse can lift its knees (think knees to ears in the jumping horse)
  • The more horizontal the humerus bone the less natural ability the horse has to lift its knees to create high action or fold it’s knee (think daisy cutter and a horse that hangs its knees over jumps)

(Note: The humerus bone along with the shoulder angle determines a short, choppy stride, not a short or upright pastern as is so often claimed.)

Gaited horses that are prized for their high knee action would thusly possess a long humerus bone orientated more vertically and likely also possess a quite open shoulder angle, well exceeding 90 degrees.  This would be the same for a Jumper that could put his knees to his ears with the exception of the placement of his knees being lower by having a shorter cannon bone; a requirement to stay sound from repeated landing concussion.

The Dressage horse will also possess a long humerus bone, but less vertical compared to the gaited or jumping horse and in most cases not as open a shoulder angle, but certainly still maintaining the minimum 90 degrees.  The shoulder slope of the Dressage horse will tend to be more laid back than the jumper.

The Hunter horse with a long, sweeping, and low daisy cutting action will also have a long humerus bone, but it will lie more horizontal limiting the ability of the knee to be raised.

The stilted front end gait of many Western horses is due to a closed shoulder angle and/or a shorter humerus bone set horizontally.

Horse #1 – QH Stallion

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Our QH stallion has very good length to his humerus bone at approximately 64%.  This trait helps to minimize the effects of his slightly closed shoulder angle.  The humerus more on a horizontal orientation giving flat movement.

 ZansParityQHStalEquineNowAd-ShoulderMarked

Horse #2 – QH Gelding

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This QH gelding also has very good length to his humerus bone at about the same 64%.  Its orientation is identical to our stallion, except that we know this horse is not standing with his front legs properly underneath himself.  If he was, then his humerus would be a bit more vertical than our first horse.  However, paired with a slightly more laid back shoulder (and the same closed shoulder angle) these two horses should move in the same general manner with their front legs.

 QHGEquineNowAd-ShoulderMarked

Horse #3 – 4yr old QH

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This horse has the longest humerus bone of the group at 67%.  He also has the most vertical orientation of the lot and with the most open shoulder angle.  Coupled with his upright shoulder and surprisingly this horse has the potential to bring his knees up the most and fold his lower leg the tightest of this group, as well to have very good scope and potential for lateral movement.   Though he should have more expression to his gait than the first two QH’s, I’d bet my own money (again) that he moves in a typical QH fashion, flat and short.  I’ll talk about why in a future article.

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Horse #4 – Arabian Stallion

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Another long humerus bone at 60%, with a vertical orientation between that of the QH stallion and the grey QH, paired with an all-around shoulder slope of 50 degrees and adequate shoulder angle gives this horse middle of the road action (neither daisy cutter nor hackney) and scope.

 BaskeAflameArabDreamHorseAd-ShoulderMarked

Horse #5 – TB Gelding

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We’ve won the lottery as here is another horse that still maintains a long humerus at 59%.  The orientation is identical to our Arabian, but with the more upright shoulder we should expect our TB to be able to lift the knee a bit higher, but the lower leg no tighter due to shoulder angle and humerus bones length being very much alike.  Both horses should possess similar scope and lateral potential.

 IvanOFTBDreamHorseAd-ShoulderMarked

Horse #6 – Paint Mare

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Our Paint mare has the shortest humerus of the group at approximately 55.5%, which still makes it long enough but she will have the least scope and lateral movement of all of our horses.  Unfortunately it’s also the most horizontally placed on a quite upright shoulder.  Still she manages to keep a minimum 90 degree shoulder angle.

While it’s a desirable trait to have a long shoulder, this horse has too much shoulder length placing the point of shoulder too low.  This low placement puts a horse more over its shoulder and onto its front end.  Horses of this construction tend to be forever pigeon-breasted.  She’s a contradiction.  The upright shoulder says she can bring the knee up, but the horizontal humerus says she can’t.  The humerus bone wins every time and so a horse constructed like this will lead with its chest when it jumps and hang its knees all day long, every day.

PaintMareDHad-ShoulderMarked

The Up And Down Of It – Shoulder Slope And Angle – Part 1

Shoulder slope and shoulder angle are two entirely different things when discussing equine conformation, yet many times the terms are used incorrectly or interchangeably. Shoulder slope references the slope at which the scapula sits in direct relation to the horizon, while shoulder angle is the angle created at the joining of the scapula and humerus bones.

Shoulder slope:  is marked from highest point of wither to point of shoulder and then measured against the horizon. The slope of the horse’s shoulder ranges between 40-60 degrees. A slope of 45 degrees is considered ‘laid back’ and is ideal for Dressage horses. A slope of 55 degrees is considered ‘straight or upright’ and is more useful in jumping or gaited horses for lifting the knee.  A shoulder slope of 50 degrees is what I call ‘utility or all-around’.

At the outer limits of range we have 40 and 60. A horse possessing a shoulder excessively laid back is still quite functional and not necessarily prone to lameness, but a horse designed like this will give their owner a headache when it comes to saddle fit. The scapula will lay back so much that it’s next to impossible for a saddle to be done up when it’s sitting in the correct position on the horse’s back. Placing it so it can be done up with the girth not around the horse’s belly puts it over the scapula.  As we know, a saddle in this position would block the ability of the scapula to move freely thusly also blocking movement of the horse’s entire front leg. Even a cutback saddle won’t always fit this conformation. The only horses I’ve ever seen carry this kind of conformation are some Friesians and some Drafts.  Note that for carriage or Draft horses, that a laid back shoulder is desired to more readily fit a collar.

 At the other end of the range, the very upright 60 degree shoulder also does not create unsoundness, in and of itself. Nor does it create a short, choppy stride as is often thought, though, a feeling of less elasticity can certainly be an outcome. What it does do is create added concussive stress through the entire forelimb, which in turn can cause unsoundness. Neither ends of the spectrum are desirable in a horse and should be avoided on principle alone, that principle being what’s best for horses and allowing them to perform their jobs without undue risk to longevity.

Shoulder angle:  is marked by adding a second line to the shoulder slope line from point of shoulder to point of elbow.  The subsequent angle created between the two lines is then measured. The angle created at the joint can range from 80-115 degrees. 90 degrees is the magic number here; anything less and the horse will be short-strided in the forelimb. No other combination of traits can make up for that short-stridedness, or nullify an angle below 90 degrees. In many cases it should be a deal breaker. Anything over and above 90 degrees is a bonus. Many of the GP jumpers who are able to bring their knees to their ears possess an angle at the higher limit of the range.

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Let’s look at our random sampling of horses and see how they measure up.

Horse #1 – QH Stallion

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Our stallion carries a typical lovely shoulder slope of 50 degrees.  It’s the kind of trait that fits a versatile breed.  Not surprisingly, though, he also carries a shoulder angle of less than 90 degrees – about 85.  This latter is unfortunately a trait that is quite prevalent in the QH breed.

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Horse #2 – QH Gelding

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This horse’s shoulder slope is approximately 48 degrees, unfortunately he too has a closed shoulder angle and more so than our first horse.  It measures about 78 degrees.  However, this is not really his actually shoulder angle, which is closer to the same 85 as our first horse.  Note that this horse stands with his shoulder angle artificially closed by standing ‘over’ his point of shoulder with his forelimbs too far under his body – leaning forward.  If he stood how he should, his shoulder angle would open a bit, but still be less than 90 degrees.

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Horse #3 – 4yr old QH

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Here we have our first upright shoulder at 55 degrees.  What surprised me was that it’s combined with an open 95 degree shoulder angle.  This combination is unusual in QH’s, more often seen in TB’s.   I wonder if this guy isn’t expressing some TB influence in his pedigree.

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Horse #4 – Arabian Stallion

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Another lovely all-around shoulder slope of 50 degrees, but to my surprise his shoulder angle is also closed at 85 degrees.  This is highly unusual for an Arabian, such that I actually went back a few times to recheck the points and numbers.  The lighting in the photo, which perfectly highlights his bones, confirms the results.   If we account for the right front leg being, perhaps, a bit too far underneath then we can add a degree or two, but it still puts the angle short of adequate.  But then I had to consider the clubbed foot, which with its too high heel is going to artificially close the shoulder angle by lifting the elbow (note it also slightly buckles the horse’s knee putting him over at the knee on that leg).  I would bet some of my own money that if we had a photo from this horse’s other side, that the shoulder angle would measure the desired 90 degrees.

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Horse #5 – TB Gelding

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As expected, our TB has a more upright shoulder at approximately 54 degrees.  The angle is ever so slightly closed at 89 degrees, but note the left front leg is a bit too far underneath the body and so our TB actually possesses an adequate shoulder angle of 90 degrees (and possibly even a touch more).

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Horse #6 – Paint Mare

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Our paint mare has the most upright shoulder of the lot at approximately 57 degrees and an adequate angle of 90 degrees.

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In part two I’ll discuss the signficant importance of the humerus bone and its direct relation to the scapula.

Loin From Above

Send your thanks to Blondemare for providing this set of photos of her horse, April, so that we might all get a chance to see the loin from above.

In the last Long And Short Of It article (Part 3 – Loin), I talked about the desirable shape of the loin from the top being more like an equilateral triangle than an isosolese triangle, and how the former is created by a short, deep, broad loin.  Well, here we have one:

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Even though this picture is taken at an angle and with the photographer standing too far forward (center body and straight on is where we like to see photos taken from to minimize distortion of angles and lengths), we can still see that this horse’s loin is deep and short.  The ribcage carries back really well and the LS joint is just a touch in front of the point of hip.

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From above we can see how truly far back that ribcage is, as well now we can see the breadth of the loin, easily exceeding the length of the loin itself (L1 – first yellow dot – to LS joint – second yellow dot).

Our horse, April, possesses a fantastic loin, one of the virtually indestructible kind.

Blondemare had photos of a second horse, but the angles of them were too great to see clearly, but I sure appreciate the time and effort she put forth.  Thank you!

 

Reminder:  I will be away from a computer for a week, so this is the last blog post until I return.  For those reading Tao, finish up Part 1 as I’ll be posting my thoughts on it as soon as I return.   I look forward to a lively discussion.   Cheers!

The Long And Short Of It – Part 3 – Loin

The loin is arguably one of the most important structures in the horse. It is inherently weak in its design, being a freespan (having no ribs to add support and strength), and therefore is susceptible to injury. The loin of the horse is equivalent to the transmission of a car; it transfers power created by the haunch (engine) forward. A mismatch of a powerful haunch (engine) to a weaker loin (transmission) all but guarantees ‘spinning tires’ and often structural failure.

To put it in simple terms;

  • The shorter the loin is in length, the more strength it possesses.
  • The deeper the loin, the more strength it possesses.
  • The broader the loin, the more strength it possesses.

The strongest loin is therefore a short, deep, broad one. This type of loin is virtually indestructible and guarantees full transmission of haunch power brought forward, but can produce a rough ride if it gets muscle bound. Think of it in terms of a body builder with their massive strength, but often times lacking flexibility. A horse with this loin absolutely must have a training focus on creating and maintaining suppleness. Of course we now know that how far the ribcage carries back plays a role in lateral flexibility. A short loin guarantees ribs that carry back well for lateral flexibility, so the potential for suppleness is clearly there with a short loin.

The weakest loin is a long, shallow, narrow one. This type of loin is highly susceptible to damage. It can combine with other traits to make a rather smooth ride because the horse that possesses it often hollows the back and becomes a leg mover, but invariably it breaks down under anything but the lightest of workloads.

Six lumbar vertebrae make up the loin.

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There is no specific loin measuring system in terms of garnering a specific percentage. We use various body references to determine its length.

1) The ‘quick and dirty’ hand measurement discussed in the Part 2b – Ribcage article. Greater than a spread hand’s width (8″) and the loin is long; about a spread hand’s width and the loin is medium, and less than a spread hand’s width and the loin is short.

2) The loin should ideally be as deep as the chest. A significant difference and a loin is very likely long. Note: Excellent riding and training can deepen and strengthen a loin.

3) The further behind the point of hip that the LS joint is, the more likely the loin is long.

4) Probably the most telling view for the loin is a top down view. Marking the points of hip, the LS joint and the first lumbar vertebrae, then connecting the points (minus the LS joint) will produce a triangle. An equilateral triangle with the LS joint inside the base line would be a short, broad, deep and strong loin, whereas an isosolese triangle is going to indicate a longer, less broad, less deep and therefore less strength.

Equilateral Triangle

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Isosolese Triangle

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Let’s take a look at our six horses, concentrating on their loins. 

Horse #1 – QH stallion:  This is a short loin with great depth.  We don’t have any overhead shots of our horses, but if we did this horse would also be broad across his loin.  Our horse with the biggest hip has a loin of more than sufficient strength.

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Horse #2 – QH gelding: This loin is longer than our first horse because the LS joint is placed further back.  If it was placed in the same location as our first horse, the loins would be identical.  Still this loin remains medium in length and has excellent depth and breadth.

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Horse #3 – 4yr old QH: This loin is also medium in length, but just.  It’s not as deep as our first two horses, but likely possesses good breadth.   

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Horse #4 – Arabian Stallion: Another short, solid loin.  It lacks a bit of depth, which I blame on the table top croup preventing engagement.

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Horse #5 – TB Gelding:  The shortest loin of our group.  It has good depth (don’t let the distended belly fool your eye).  This is another one that likely isn’t particularly broad and thus why it isn’t as deep relative to the shortness.

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Horse #6 – Paint mare:  Here we have a long loin that lacks significant depth and likely breadth as well.  This is a highly susceptible construction and we can be thankful that she doesn’t possess the same kind of hip as our first three horses or she’d be in big trouble.

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   Summary 

Based on what we have analyzed so far; hip, back, loin, lumbo-sacral joint, ribcage, to a lesser degree the withers, and setting aside any personal or breed biases, or anything else we might know or suspect about the individuals in question, how must this group of horses be ranked? Before you peek, think about it. Which horse at this stage seems to have the most athletic potential AND ability to stay sound through the back and loin doing whatever task they may be asked in the future…all other things being equal and relative. And who appears to have the least? And why?

In reverse order:

6. Horse #6, Paint mare. Her back is long, her loin is long, her ribcage does not carry back well, and neither do her withers. She possesses adequate hip length and might very well produce some easy gaits to sit to by means of hollowing the back and being a leg mover. Of the group, this horse requires the most knowledgeable rider to prevent topline breakdown and improve its strength.

5. Horse #4, Arabian Stallion. There is just no getting around the table top croup, it’s just that severe of a fault and the camel withers don’t help. What saves this horse from breaking down through the topline are the shorter back, the short loin and the ribcage that carries back well, all of which add significant structural strength.  While this is no novice ride, this horse is far less likely to succumb to topline breakdown from hollow riding than our Paint mare.  For that reason he garners one spot up from the bottom.

4. Horse #2, roan QH gelding.  Simply based on having the poorest LS joint placement of the remaining candidates, increasing the difficulty of engagement. 

The next two placings are very close and arguments can be made for switching them based on discipline and type of issues a person prefers to deal with. 

Tie for 2nd – Horse #1, QH stallion and Horse #3, grey QH gelding.  Our stallion is shorter backed, has a short, deep, broad loin, a huge hip, a good LS joint placement, and ribs that carry back well giving us super longitudinal strength, super power potential, super potential to engage, but perhaps lacking a bit of lateral flexibility through the body compared to the grey gelding with a longer (yet still medium) back, a medium loin (that does lack a bit of depth), a big hip, a very good LS joint placement and ribs that carry back well.  His withers aren’t as well defined or designed, but still functional.  This one may possess a bit more flexibility, but also may tend to evade through the body more.  Still plenty of power and engagement ability, this one might very well ride a bit smoother.

1. Horse #5, TB gelding. The horse with the least hip length currently heads our list because there is so much strength in the rest of his topline that that lack of pure power can be overlooked – as long as we’re not going to ask him to be a sprinter, or an International/GP competitor. He has a great short loin and LS joint placement, withers and a ribcage that carry back really well to add longitudinal strength to the medium back and should possess a good amount of lateral flexibility as well.  This horse should present as the most viable individual, for the most people, with the widest range of knowledge and ability.  There is not so much power or movement potential that a beginner/novice couldn’t handle this horse, and yet there’s enough longitudinal strength to protect the horse against that sack of potato rider.  Additionally there’s plenty of lateral flexibility and engagement potential that a more advanced rider could also enjoy this topline. For those reasons this horse takes the top spot – for now.

We’ve only just begun our analysis of this group of horses; there’s so much more to look at and consider. I suspect *wink* that the current rankings may change as we delve deeper into the conformation of these individuals. Will your original choice end up at the top of the list? (Insert appropriate musical cue) Stay tuned for the next series of articles discussing body levelness and shoulders.

The Long And Short Of It – Part 2b – Ribcage

There isn’t a lot of range of motion between the equine vertebrae, a lot less than people think. I mentioned in part 2a of this series that a long back isn’t necessarily more flexible than a shorter back; sometimes it is, sometimes it isn’t. And here’s why:

The back is made up of thoracic vertebrae and lumbar vertebrae. The thoracic vertebrae have more range of motion between them than the lumbar vertebrae. Indeed, the lumbar vertebrae are all but fused in the adult horse to help add stability and strength to that section of the back, which is the weakest and most susceptible because it’s a freespan having no ribs to support it. Youngsters show more flexibility and ability to ‘twist’ than an adult because their vertebrae aren’t done growing and ‘setting’. Think of it like a baby’s skull that is soft and still in ‘pieces’ and then as the baby grows and matures the skull hardens and fuses. This is just one of the many reasons why riding young horses can be detrimental to future soundness and it’s also a main reason why so many racehorses hurt their backs, but that’s a topic for another day.

If a horse has a medium length of back, but a loin that is proportionately long, then that horse will have less lateral flexibility than a horse with the same medium length of back, but with a loin that is proportionately shorter. Let me phrase it another way: the longer the loin proportionately, the longer the freespan of relatively immobile vertebrae, therefore, the less  lateral back flexibility.

So now we want to take a closer look at our six horse’s backs and determine how much potential flexibility they possess. First we want to see how far the ribcage carries back. (I’m saving the loin for our final part of the series.) The further the ribcage carries back, the more strength it adds to the back (similar to withers that carry back well), AND the more potential for lateral flexibility because that means the more thoracic vertebrae length we have proportionately.

There are two methods for determining how well the ribcage carries back; one is a ‘quick and dirty’ method and one is our trusty measure and calculate method. We’ll start with the latter.

  • A horse with the maximum potential for lateral flexibility (which, btw, is the ability to perform a volte or 6m circle) will possess a ribcage that exceeds 100% of its back length.
  • A horse that possesses an average potential for lateral flexibility will possess a ribcage close to 100% of its back length.
  • A horse that possesses a below average potential for lateral flexibility will have a ribcage well below 100% of its back length.

Remember, though, that all other things would have to be equal. For instance, a horse with a medium back that had a ribcage of 95% would have less lateral flexibility potential than a horse with the same medium back length that had a ribcage of 110%. BUT, a horse with a medium back that had a ribcage of 110% would have more lateral flexibility potential than a horse with a short back and a ribcage of 110% because the medium back possesses more thoracic length to start with than the short back regardless of having the same ribcage length. Still with me?

To determine the ribcage length we start by measuring back length (highest point of wither to LS joint).  Then we draw a body length line (point of shoulder to point of buttock) and a second line from highest point of wither to the last rib.  Where that second line intersects the body length line is the end point of our ribcage.  We then divide the ribcage length by the back length to get our ribcage percentage.

Our skeleton with the points and lines marked:

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Horse #1 – 10yr old QH Stallion

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So, you’re staring at our first horse and maybe wondering where is that last rib?  This is another point on a horse that can sometimes be hard to identify in a photo.  It is always best to look at a horse in real life, make a guess, and then palpate to determine how close you were.  Over time your eye develops and you start to be able to pick up the nuances of muscle, skin, shading and lighting that can indicate, not just in real life, but also in a photo where such a point is.

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Without even measuring we can see that the ribcage line is almost as long as the back line.  My measurement is about 97%, so that’s a ribcage that carries back well, adding strength and flexibility to the back.  But remember, this horse had a short back, so even though the ribcage length is very good, that overall shortness does bite into potential lateral flexibility.

Horse #2 – QH Gelding

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This horse doesn’t have the same muscle definition as our first, so judging where the last rib resides is more difficult.

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Here’s another one where we can see the ribcage line is very close in length to the back line.  This horse measures almost 95.5%, so close to horse #1.  This horse also had a rather short back (just a touch longer than horse #1), so we can conclude that both horses are likely to have similar lateral flexibility potential.

Horse #3 – 4yr old QH

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The sun helps a little bit here to locate that last rib.

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This horse’s ribcage measures pretty much right on 100%, so carries back well and with a good amount of lateral flexibility potential.  This horse also measured at the longer end of the medium spectrum, so there’s even more potential for flexibility.

Horse #4 – Arabian Stallion

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Another horse with a ribcage that carries back well at 95%, but with a back length that falls on the short side.

Horse #5 – TB Gelding

How does this horse’s ribcage measure up to the previous ones?

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If you guessed that this horse’s ribcage carried back the furthest, then good eye!  Finally, we have a horse with an exceptional ribcage at 104%.  Our TB and our grey QH had similar back lengths, being at the higher end of medium in range, but our TB has a ribcage that carries back further, so should possess a bit more lateral flexibility potential.  Indeed, this horse should have the most potential of any of the other horses in that area.  And lastly, remember that the further the ribcage carries back, the more strength it adds as well.

Horse #6 – Paint Mare

How far back does this horse’s ribcage carry?

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Our poor Paint mare takes another hit with a ribcage that carries the least distance back at just under 91%.  She also possessed our longest back of the group right at 50%.  So here is a situation where longer is NOT more flexible.

Now that you’ve got the hang on the measuring method, I’ll tell you about the ‘quick and dirty’ method.  Place your hand between your horse’s last rib and point of hip.  More than a ‘spread’ hand’s width (8”) is a ribcage that doesn’t carry back very far.  A ‘spread’ hand’s width is a ribcage that carries back well, and less than a ‘spread’ hand’s width is a ribcage that carries back very well.  You cannot have a ribcage carry too far back.  The further back it goes, the better.

The Long And Short Of It – Part 2a – Back

The rider sits on the horse’s back and is carried forward. But the horse’s back is not designed to carry weight, and that is why so many horses travel with their backs hollow and tense. This is where I tell you to read a certain one hundred page book on skeletal, ligamental and muscular anatomy, center of gravity, the ‘ring of muscles’, how the horse must be ridden to counter this physical weakness, why it so often goes wrong, blah, blah, blah. The truth is if everyone knew that we wouldn’t be ‘here’ talking about something as simple as back length. Someday we’ll tackle that topic, but not today.

For now it’s good enough to know that a long back in a horse is a fault.   It lacks longitudinal strength and often sags under the weight of a rider, creating a ‘leg mover’ that certainly can give a smoother ride, but only at the expense of the horse.  Prime examples of leg movers are gaited horses that tense and hollow their backs to be able to move their legs in any number of timed sequences, as opposed to your ‘back mover’, the Dressage horse, that swings freely through the loin and back.  This latter requires a rider to have a supple lower back that follows and absorbs this movement to prevent being launched out of the saddle.

Additionally on the subject of longitudinal strength; without it the horse cannot easily maintain engagement.

A long backed horse often presents the rider with the additional challenge of trying to keep the horse straight from dock to poll.  Don’t, however, confuse that with lateral flexibility.  Indeed, a shorter backed horse is often more laterally flexible than its long-backed counterpart.  I will address that in an additional article (2b) in this series.

An excessively short back is also a fault in a horse.  Such a configuration doesn’t allow for enough room for a saddle to be placed, as well, sets the rider’s weight on the loin rather than on the ribcage.  It’s never a good idea to ride a horse from its loin; the weakest portion of an already weak structure.

  • A long back: >50%
  • A medium back: 45-49% (Note: 45% is considered ‘ideal’ for a riding horse; the ‘perfect’ length to provide lateral flexibility and longitudinal strength)
  • A short back: < 45%

To determine back length we measure the horse’s body length and divide that number into the back length number to arrive at a percentage. 

  • Body length is measured from point of shoulder to point of buttock. 
  • Back length is measured from highest point of wither to lumbo-sacral joint.

Here is our trusty skeleton horse with the points marked in red.  The highest point of wither is usually thoracic vertebrae four (T4) and the lumbo-sacral (LS) joint is located between lumbar vertebrae six (L6) and sacral vertebrae one (S1).  I’ve added an extra dot marking the highest point of croup (sacral tuber – top point of the pelvic bone) to help establish the location of the LS joint since it can’t actually be ‘seen’ in a photo; residing 2-4 inches below the surface of the skin. 

The best way to locate the LS joint on a horse is to palpate the horse’s back.  As you move along the length of the back you can feel the individual spines of the vertebrae, then you’ll hit a ‘mushy’ spot and finally vertebrae spines again.  Below that ‘mushy’ spot is the LS joint.  For article purposes, we’ll use the highest point of croup (which is located behind the LS joint) to help us find the LS joint in photographs.

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The LS joint is the most important trait to discuss in horses in terms of athletic potential and movement.  The entire hindquarter of the horse pivots on this joint and its location relative to the horse’s point of hip is instrumental to a horse’s ability to engage and collect.

I’ve added more dots to our six candidates and it’s time to measure back lengths.  The LS joint is marked in a different color and though I’ve placed that mark at the skin level of the horse for measuring sake, remember that it resides 2-4 inches below the skin surface.

Horse #1 – 10yr old QH Stallion

Take a look at him unmarked.  Where do you see the points and how does his back length look to your eye?  Imagining a saddle on the horse and seeing how much space between the back of it and the start of the hip is sometimes helpful.  If there’s a lot of room, chances are the back is long.  If no room, then the back is likely short.

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This horse has a back length of approximately 41.5%.  That falls clearly in the short back range, giving this horse a high degree of longitudinal strength.  Did you imagine a Western saddle on him and where the skirt might come to?

Horse #2 – QH Gelding

How does this horse’s back length compare?  Does it look longer or shorter?

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This one measures almost 42.5%, so a full percentile longer but still falling in the short range and possessing a high degree of longitudinal strength. 

Start to take notice of the relationship of the highest point of croup, point of hip and LS joint, and how they differ for every horse.

Horse #3 – 4yr old QH

Like the first time around, when it was difficult to spot his point of shoulder, it’s equally as difficult to spot this horse’s highest point of wither.  He has lower withers in general, which is not a fault and different than ‘mutton’ withers, which is a serious fault in the horse. 

How does his back length look?

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If you thought this one looked longer than the first two, then you get a gold star.  This horse is approximately 48% falling in the medium back length category.

Horse #4 – Arabian Stallion

Here we see a set of prominent withers.  In this case they are also ‘camel withers’.  Though difficult to detect because of the mane and photo background, look closely.  Follow the top line of the mane and you’ll see a significant dip in front of the wither and then the wither drops off abruptly.   A dip in front of the withers can indicate a few different things, so not all horses with a dip there (and an abrupt ending) have camel withers.  Let’s compare horse #2, our roan QH.  The dip in front of his withers is easily gotten rid of with good riding and training, which would significantly change his neck musculature and fill in that dip.  Our Arabian stallion, though, already has way better neck musculature (mostly because it’s a stallion’s way to arch and telescope their neck to get the chicks) and still a big dip.  There is no amount of correct riding or training that will get rid of it.  Camel withers do not function as well as better constructed withers; that as a ‘fulcrum’.

Scroll back to the skeleton horse for a moment and look at the ‘spines of the wither vertebrae’ that make up the withers.  Those spines vary in length for every horse.  Thoroughbreds generally have very long spines compared to Quarter Horses.

Back to our Arabian stallion; how does his back look?

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He too falls into the short back category at almost 43.5%.

Horse #5 – TB Gelding

Now that you’ve seen three short backs and one medium, has your eye gotten good enough to guess where this horse’s back length falls?  The mane and the background of this photo make it hard to see that highest point of wither.

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If you guessed the longest back of all so far, but still falling in the medium range at 49%, then you were right.  What is most significant, though, is the placement of the LS joint.  Remember this horse had the shortest pelvic length of the group, representing the least power potential by falling in the poor category.  But I also said the horse had two ‘saving graces’, one of them being exceptional location of the LS joint, and earlier in this article I stated that the LS joint was the most important trait to discuss when talking about athletic potential and movement . 

Here we clearly see that the LS joint is located the furthest in front of the point of hip of any horse thus far.  That is most advantageous for ANY horse, ‘adding’ length to the hip and thus power potential.  In this case that poor length of hip is moved into the adequate/average category.  Is it then possible that the LS joint placed ‘behind’ the point of hip (such as seen with our roan QH) might ‘subtract’ length and thus power potential from the hip? (Rhetorical question)  Additionally and even more importantly, an LS joint placed in front of the point of hip makes engagement, as a whole, easier to achieve.

Horse #6 – Paint Mare

Last chance to test your eye on the horse with the hardest point of wither to identify.  I’m not entirely convinced I’ve got it right.

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As it’s marked this horse falls long with a back of 50%.  If I’m off at all, it’s a touch to the long side, but either way we’re looking at a back as long as we ever want to see on a horse, and we’d really prefer it to be shorter.

There is one more thing I’d like to point out concerning back strength.  The further withers carry into the back, and the gentler they taper off into the back, the more strength they add to a back.  Of this group, our TB has the nicest set of withers that gently taper off the greatest distance into the back, adding strength.

It’s time now to go out into your barn and palpate your horses’ backs and find the LS joint and its relationship to the point of hip.  Look at their backs and guess their lengths, then measure to see how close you were with your estimations.  Look at their withers, are they prominent and drop off abruptly, or are they lower and flow smoothly into the back, or some combination.

The Long And Short Of It – Part 1 – Hip/Pelvis

Conformation is an extensive topic and many get overwhelmed.  To help make it easier to digest, I’m going to break things down into really small chunks and hope that prevents choking on the technical data. 

Following is part one of three discussions on the length of the hip, back and loin, respectively, and what that means to the horse.  For clarity and comprehension sake assume the discussion is always about ‘riding’ horses, as opposed to ‘draft’ or ‘racehorses’.   Many aspects will apply to the latter two as well, but there are also exceptions.  I will periodically make mention of those exceptions, but for everything else go with ‘this applies to riding horses regardless of discipline’.

As mentioned in the article ‘To Plow Or Not To Plow’, hip length is important for power potential; the more length, the more power potential.  This potential is based on two principles; more length for muscle mass, and more length for leverage.   There is no such thing as a ‘too long’ hip in equines, but there certainly is ‘not having enough length’

The horse needs to possess power to perform tasks.  Arguably, some tasks require more power than others, but it also takes power to engage and collect and while we don’t need every horse to collect to the highest degree, we do need them to engage to protect themselves and perform even the simplest tasks correctly and well.

I’m going to use the same set of horses for all three parts of this series.  I’ve randomly picked individuals from sale ads; some from www.dreamhorse.com/ and some from www.equinenow.com/

  • Poor hip length: < 30%
  • Average/Adequate hip length:  30-32%
  • Good hip length:  33%+
  • Great hip length:  35%+

To determine hip length we measure the horse’s body length and divide that number into the hip length number to arrive at a percentage. 

  • Body length is measured from point of shoulder to point of buttock. 
  • Hip length is measured from point of hip to point of buttock.

Here is a picture of the horse’s skeleton with the three points marked (in red) so you can see where to find the bony points.  Palpating your own horses will improve your ability to spot the points on other horses without touching.  It is harder to see these points when covered in flesh, and even harder sometimes in photos.  We often use differences in lighting and shading to spot the points in photos.

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Horse #1 – 10yr old QH Stallion

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Because of the amount of muscle and how smoothly it ties from one body part to another it’s more difficult to see the points, particularly the point of shoulder.  There is a shading difference and a ‘wrinkle’ in the skin/muscle that helps us find the point of hip.  Being even a bit off in the points can greatly affect the measurement from a photo.  When the eye gets good enough you no longer need to get out the ruler and protractor to have a real sense of the horse’s proportions, ratios and angles.

Below I’ve marked where I believe the points to be.  Now measure body length and hip length and divide the hip number by the body number to come to a percentage.

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My measurement comes to a hip of just under 36.5%.  Our figures are going to vary a little bit depending on how big (or small) the diagram is on our screens and how accurate we each are at measuring from point to point, but we should all be getting a hip figure that clearly states this horse has ‘great’ length of hip.

Horse #2 – QH Gelding

The roaning on this horse makes it a bit harder to see the point of hip, but he’s got a little dark speck right on the front edge of it.  The point of shoulder is easier see.  Now, before you peek, does this horse appear to have as much hip length as the first horse, or less?  If less, do you think he’ll still fall in the ‘great’ category?

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My measurement on this horse’s hip is a bit under 35%, so not as generous as horse one, but certainly a quite good length of hip.

Horse #3 – 4yr old QH

This horse has lots of smooth muscling on his haunch, especially pants muscling.  His pelvis is steeper, but does it have length to it?  Does it possess ‘good’ length?  His front end muscling is very muddy, so seeing the point of shoulder is difficult.

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I measure about 34.5%, so another one with a quite good hip length.  Don’t get fooled by a steeper pelvis that at quick glance can appear short.  Quarter Horses get knocked for some disastrous traits purposely bred into them over the years (and we’ll get to those at some point down the road), but one area where they rarely fail is in pelvic length.

Horse #4 – Arabian Stallion

It’s really easy to see the point of shoulder and buttock on this horse.  The point of hip is a bit harder, but there’s a darker spot of shading that helps us locate it.  Now that we’ve seen three very good lengths of hip, what is your first impression about this horse?

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This one is about 31%, falling in the adequate/average category.  It’ll get the job done for the horse, but he isn’t going to be setting the world on fire in the power department.  He’s a much lighter built horse, and this is not a breed we think about for pure power but they have been praised for their speed.  Speed develops from power potential, though, so this one is not going to be particularly fast for his breed. 

There is one thing to take special note of; this horse possesses what is termed ‘table top croup’.  This is a significant fault in a horse as it makes engagement and collection more difficult to achieve.  With the pelvis so flat, the natural tendency will be for hollowing the back, trailing the hocks, and high-headedness.

 Horse #5 – TB Gelding

So what are your first impressions about this guy’s hip?

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If you thought, ‘well, that doesn’t look like a very good length of hip’, then you were right.  This guy has about 29% and that is poor.  He does possess two ‘saving graces’.  One of them is an exceptional lumbo-sacral joint placement.  This is a situation where a trait or group of traits can significantly balance/nullify/make less weak a poor trait.  The second ‘saving grace’ will be discussed in Part 3 of this series.

Horse #6 – Paint Mare

So, what do you think about this mare’s hip length?

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If you guessed adequate/average then you were right.  She’s about 31%, same as the Arabian stallion.  I suspect, though, that some of you thought she fell into the poor category as the TB gelding before her. 

We’re going to talk more about this one in Part 3 of the series as well, since this horse – even with the better hip length – is a far weaker individual than the TB gelding with the poor hip length.  This is a case exactly opposite to that of the TB gelding; here we have a horse that possesses a faulty, but highly significant trait, which overrides many good traits and makes the entire individual weak.

Take a look in your barn and around the Internet and test your eye.  Look at hips and guess at their length then take the time to find the points and measure to confirm or correct your estimations.  It’s the only way to develop your eye.