Hello Everyone!

It takes my vehicle breaking down on the side of road on Highway 57 in Ina, Illinois, with my dog Abilene, and a 1.5 hour tow truck ride to the Mercedes dealership in St. Louis, MO for me to be stirred to write this blog.  It was my conversation with the tow truck driver, Michael, that motivated me to think about my approach on this subject.  Michael is a hunter, fisherman and gardener.  His family grows, hunts and fish for their food as he recognizes that their overall health will be better by not eating the abundance and prominence of processed food that is available everywhere here in America.

We were having a conversation about deer hunting and how his favorite part of the deer was the tenderloin.   He said to me:  “Did you know that muscle, the tenderloin, is responsible for a deer to be able to jump as high as they do and run so fast?”  I looked over at him completely baffled and amazed by his comment and said:  “Yes I do.  It is the most important muscle in any quadruped”.   I asked him where he learned this information and he said:  “It just makes sense as it is the only muscle protected and attached to the bones under the spine, so it has to be extremely important”!   Michael, a tow truck driver from Illinois, understands the importance of this muscle better than the entire equine veterinary sport horse profession as of June 2026.  His next words left me in awe and deep respect for him as a human being, father and husband as he said:  “Those things in life that are most important and tender need to be protected, like my daughter and wife, or like the tenderloin”.

I sat there nodding my head in agreement with Michael’s blue-collar wisdom about his love for his family, deer hunting and the iliopsoas muscle.   I contemplated the questions below in my mind as we drove down the bumpy Illinois highway and watched my Mercedes Sprinter van on the flatbed in the passenger rear view mirror:

Question #1:  How is it possible that the equine sport horse veterinary profession has come so far away from practical and applicable knowledge even with all the new diagnostic equipment available?

Answer:  A complex multifactorial problem that includes:  1. Lack of education.  2. Lack of curiosity.  3. Lack of critical thinking.  4.  Acceptance and normalization of a substandard level of practice that is “good enough” otherwise known as the “status quo”.

Question #2:  How is it possible that the veterinary academic institutions are so out of touch with the realities of equine practice and sports medicine?

Answer:  Another complex multifactorial problem of “Ism-Ism”.  If you do not know what this word is please read my last blog as I am the originator of this word.

Question #3:  How is it possible that the equine veterinary profession does not understand that the Iliopsoas Muscle IS the most important muscle in a sport horse, besides the heart?

Answer:  This question is NOT a complex multifactorial problem.  Michael, a tow truck driver from Illinois, not an equine veterinarian, understands the function, location and divine taste and tenderness of the iliopsoas/tenderloin muscle.

The real answer for all three questions came to me as the St. Louis Arch came into closer view and a billboard sign for learning to read at the YMCA passed by quickly.  Learning to read or not being able to read crossed my thoughts and the word illiteracy came to mind.  I realized that the equine veterinary profession has SCIENTIFIC ILLITERACY.   Yup, equine sport horse veterinarians are illiterate to the SCIENCE of their own PATIENTS!  They can read the words however are illiterate to their meaning and function.

So I Googled “science that is illiterate”.  Who knew that there was a definition for the scientific illiterate?  AMAZING and how I love AI for these random definitions of facts!

Scientific illiteracy definition:  The lack of basic scientific knowledge, understanding, or reasoning skills necessary to interpret scientific concepts. Merriam-Webster

Illiterate people cannot read.  Scientific illiterate people can read however have chosen not to continue to learn from the words and knowledge they have read.  What they knew from veterinary school or going to an AAEP conference is a “good enough” or “has worked for most” mindset that predominates.  This “good enough” mindset does not work for those difficult complex lameness cases as the veterinarians reasoning and critical thinking skills are completely illiterate to words for solutions.  Thus the words “retirement”, “EDM”, “pasture ornament”, “behavioral”, “nothing I know to do”,or  “broodmare” are words of literacy they understand clearly and use to owners and trainers due to their scientific illiteracy.

How do we solve this problem of illiteracy by the highly intelligent?  Who knew that if you ask that question to Google AI this is what comes up:

Solving scientific illiteracy involves shifting from rote memorization of facts to cultivating critical thinking, enhancing accessibility to accurate information, and engaging the public through hands-on, inquiry-based learning. Effective approaches combine formal education reforms with community-based outreach to make science relevant to daily life. [1, 2, 3, 4]

The educational system of rote memorization of facts is definitely one of the prominent problems.  I experienced this form of teaching while I was in veterinary school only to completely purge that brain-crammed information after the examination, never to remember any of it again.  Veterinary Boards, same thing but “necessary” to become a veterinarian.  One needs to memorize information as pharmacology, parasitology, virology, and anatomy are topics that require this process however if you take the time to understand the information, it is more likely to be recalled at a later time in one’s memory.

Anatomy is the most important subject that any doctor, technician or nurse needs to know to perform their job.  In veterinary school it is not a primary topic as most students have one semester to cram the anatomy of horses, dogs, cats, ruminants, and birds into their trepidative riddled brains.  How do you remember anything when you have 5 species to “learn” and be tested on this rote and brute force memorization process so that one can become a veterinarian?   This IS the primary problem!  How does one solve this problem?  Simple…TEACH ANATOMY!  Teach functional anatomy, NOT rote or brute force memorization.

People need to understand HOW something works BEFORE they can ask the right questions to solve problems in that system.  The “system” does not matter whether it is a horse, computer program, electrical grid, assembly line at a Ford truck plant, or an alcohol/ethanol distillation plant.  It is the critical thinking and reasoning skills needed to work forwards, backwards, up or down to find where the problem may be and how IT is affecting the SYSTEM.

The Iliopsoas is three muscles combined and interconnected, not ONE MUSCLE!  How many people know that trivial fact?   Not many veterinarians as most think it is one muscle, including most of the world.  Chefs, yes cooking chefs, know this muscle as three parts: the Tenderloin with its tampering Tail, the Chain and the Heel.  Three muscles with their interconnectedness that is delicious to eat but also the ONLY muscle that engages the “ENGINE” of the horse!

The most important point is that this muscle in its entirety is UNDER THE SPINE!  The only way to palpate it is RECTALLY and even then a person can only reach a small portion of the muscle due to its extended length!  If you are an owner, bodyworker or physiotherapist, this means that you CANNOT palpate, reach or touch this muscle from the OUTSIDE of the horse!  THIS IS A FACT!  ONLY veterinarians can reach this muscle BY RECTAL PALPATION!  This also means IT IS DEEP and inaccessible to everyone except veterinarians!   So IF you think you can physically touch and have an effect or affect this muscle in any way from the outside of the horse, YOU CANNOT!   Therein lies the biggest problem with Iliopsoas injuries in sport horses!

Let’s go through these 3 muscles that are under the spine and learn their function:

1. The Psoas Major Muscle:  The Tenderloin and tampering Tail.  This muscle starts at T15-T16 (tampering tail) and expands caudally (towards the tail) and laterally (away from midline) to L6-S1 (6th lumbar vertebrae to sacrum).  The Psoas Major tail starts to expand laterally from its narrow attachment (literally) to the ventral (bottom) surface of T15-T16-T17-T18 thoracic vertebrae.  It expands exponentially laterally and in diameter (thickness) as it attaches to the ventral surface of the long transverse processes of the six lumbar spine vertebrae.   The Psoas Major is the most important primary muscle that contracts and relaxes to control flexion and extension of the “Engine” of the horse.  The “Engine” of the horse is the movement of the Lumbosacral & Lumbosacral-Intertransverse Joints & Intertransverse Joints!   Bet you never heard of these joints from your veterinarian?  If you have, kudos to them as they are one of the few who may understand something of biomechanical importance in the sport horse or they have come to one of my seminars or listened to my podcasts.  What is its function?  It is responsible for lifting/picking up the horses hind limb and bringing it forward plus flexion of the lumbosacral & lumbosacral-intertransverse joinst & intertransverse joints.
2. The Psoas Minor Muscle:  The Chain.  This thin non-contractile muscle (meaning it does not contract and relax) is attached to the vertebral bodies from T15 to L6-S1.  Its purpose is proprioception and stabilization of the vertebral spine.
3. The Iliacus Muscle:  The Heel.  This muscle is located and attaches to the lateral ventral surface of the ilium/pelvis at the Tuber Coax.  It dives ventrally and interconnects its fibers and distal muscle body with the Psoas Major combining in unison to insert on the lesser trochanter of the femur medially (inside).  Short and thick it has strong contractile properties that independently are responsible for shear force stabilization of the ilium/pelvis during turning, circling and pivoting.   Its codependent interconnectedness with the Psoas Major is responsible for lifting/picking up the hind limb up and bringing it forward.

Parts of the Tenderloin

Equine Iliopsoas

Now that you know the function of each muscle what does it all mean putting it together?  What are the clinical signs of an injured or dysfunctional Iliopsoas muscle?   Below is a list though not complete:

Standing:

1. Stocking up of one or both hind lower limbs
2. Stands parked out without rider
3. Stands parked with rider or equipment on
4. Shifting hind end from one limb to another
5. Jacks feet/shaving up in the stall
6. Pushing/sits on stall wall
7. Wide based hind limb stance
8. Acute or chronic lumbar & pelvic muscle tension
9. Difficulty with farrier of hind limbs.
10. Difficulty picking up limb or inability to pick up limb
11. Difficulty picking up and holding the limb up
12. Difficulty bringing the hind limb back

 Worn off Toe From Dragging

Picture Interference Hind Limb

Parked out Abnormal Stance

Parked Out & Wide Based Behind

Resting One or Shifting Hind Limbs

Wide Based Stance

Movement of hind limbs:

1. Decreased protraction:  Picking up and bringing the limb forward/cranial
2. Does not land flat
3. Toe ticking, stabbing or dragging
4. Interference of one or both hind limbs
5. Plaiting or rope walking where one or both hind limb come medially when bringing the hind limb forward
6. Decreased hock separation, choppy shortened stride at trot or canter
7. No push or engagement of hind end
8. Out behind, cannot sit, turn or stop on haunches
9. Cantering problems:  choppy-poppy, refusal
10. Lead change problems
11. Haunches stuck to one side
12. Drifts to one side of jump, or rotation of pelvis while jumping
13. Cannot hold pivot hind limb on spinning/turning
14. Tempi and pirouette difficulty
15. No stride length
16.  Roll back problems
17. Gaiting issues (unable to quarto, rack, gait or running walk)
18. Disunited:  Front end in one county the hind end in another
19. Funky hind end waddle or moves like corn cob up butt
20. Weird almost gaited looking shuffle behind instead of trot

Iliopsoas Injury & Pelvic Dysfunction

 Canter Choppy and Waddle Iliopsoas Injury & Pelvic Dysfunction

Plaiting, Toe Stab/Tick/Drag with Iliopsoas & Pelvic Dysfunction

Severe Iliopsoas Injury & Pelvic Dysfunction in a Draft Horse

Just so everyone knows, I will not, nor do I look at any social media comments that people make.  I am amazed especially by the really arrogant comments about how “you have the answer and solution to why the horse is lame or how to fix the problem”, from those who are not veterinarians.  REALLY?  These boastful arrogant comments are sent to me as a laugh, via other veterinarians,  for their complete and utter absurdity.  It is another verification of complete disrespect to my profession and is a huge contributing factor to the problem of why veterinarians have the highest rate of suicide and why no one wants to become an equine veterinarian.  Equine veterinarians are leaving the profession left and right due to emotional fatigue and disrespect.  Everybody is an armchair quarterback and fulfill the definition to a tee of the Dunning-Kruger Effect!  Come on people….be nice and be a kind human being to others.  It is so simple to be kind and love one another instead of being a know-it-all or simply being an asshole with entitled passive aggressive comments.  Luckily my web designer extraordinaire Maggie summarizes most things and gives them to me in a nice constructive way as she knows I only care about educating people to help more horses.

Education is key for everyone to learn however my profession and equine professionals are the key for change!  As an owner can you scan and understand the images on an ultrasound machine, take proper back/cervical radiographs, inject the hocks-coffin-stifle joints, do colic surgery or suture a huge wound?   Do you know the complex anatomy of the cervical or thoracic spine?  Can you name all the nerves that you are testing and understand how to do a proper neurological examination?   The answer is NO to all of these things so please stay in your lane and keep the unnecessary armchair quarterback comments to yourself.  We, my profession, with all of its faults will be better with an educational system based on practical functional medicine that I am trying to develop.  It takes time, patience, support and most importantly respect!  My pep-talk summary:

1. More love, kindness and positive action is needed for helping horses!
2. Less opinions from everyone!
3. More learning for all of us!

For those who still want to fulfill the Dunning-Kruger Effect, all the horses in these videos were worked up and blocked for lower limb lameness EXTENSIVELY!  No adjustment, bodywork/physiotherapy, nerve block, deworming, supplement/herb, training method, bigger bit, bigger spur or whatever will fix these problems as IT IS THE ILIOPSOAS MUSCLE THAT IS INJURED CREATING PELVIC DYSFUNCTION!   

Unfortunately there are literally hundreds of thousands of horses competing with Iliopsoas Injury & Pelvic Dysfunction out there in the world.  I cannot go to a horse show, look at a Reel on FB or watch an event online without seeing horse after horse with Iliopsoas Injury and Pelvic Dysfunction.  I am sorry to say folks but the cause of this unsolved and undiagnosed lameness that you may be seeing or dealing in your own horse is simply due to the fact that my profession is scientifically illiterate!  My job and purpose is to fix this illiteracy by giving the equine veterinary profession the scientific facts and knowledge to gain literacy.

Next blog will be on exercises and things that YOU CAN DO to help your horse if you see or feel under saddle the long list of clinical signs above.

Please do your part to correct the scientific illiteracy present in the horse industry and my profession by sharing this blog on social media and with your horse friends.  We ALL need to work together to help educate people worldwide to help more horses that have no say or voice, only behavior, posture or movement as their means of communication.

Be the Voice.

Be the Advocate

Always Put The Horse First!

AJD