Green Animal Osteopathy / Martine Groeneveld

13/07/2025

A great few weeks of travel seeing horses in many different states, from Boston down to Savannah, and back to the west coast, with a stop also in Colorado. Heat wave everywhere with many horses suffering from heat related issues.
Was able to do some beautiful hiking as well.

21/06/2025

This is a 14yr old mare. According to the owner, she’s doing well.

We can see some interesting clues about her body in her front teeth.

-What would her overall metabolism be like? Digestive health? Immune system health?
-Which side would she prefer to bend to? Which canter lead would be easier for her?
-What would the condition of her feet be like? (Healthy/strong, or weak?)
-Which front foot would most likely be the lower one?

Thank you for the comments.

Explanation below:

TARTAR
Tartar is visible on the upper part of her front teeth. Just as in humans, it is hardened dental plaque, and is formed by bacteria and food particles mineralizing on the teeth.
An important question to ask is always; “Why does this horse form tartar and the other horses (in the same barn, on the same diet) don’t?” “What is it in this horse specifically that causes the body to create this?”

Contributing factors for the forming of tartar are for example:

-High level of calcium in saliva:
The hormone Calcitonin plays an important role in regulating the level of calcium in the blood (therefore saliva) by decreasing it. It’s produced by the Thyroid gland, the main center of the body’s metabolism.
A higher level of calcium could mean a lower level of Calcitonin production by the Thyroid, which could indicate a lower functioning Thyroid and therefore metabolism.

-Bacterial imbalance in the mouth:
The oral and gut microbiome influence each other. Dysbiosis in the gut may shift the overall immune responses and microbial balance in the mouth, increasing plaque and inflammation.

-Changes in salivary pH:
Digestive dysfunction (for example liver, stomach or gut issues) can shift the body’s pH (and saliva pH) to an overall more acidic state, stimulating bacterial growth and inflammation.

To summarize, dental tartar could be an indication of:
*a low functioning Thyroid and slower metabolism
*dysbiosis in the gut microbiome
*digestive dysfunction

HOOF CONDITION
Based on altered metabolic and digestive health, it’s very well possible the condition of her hooves is altered as well due to lower nutritional uptake. The toe crack on the right front could be an indication of changed hoof quality and needs further investigation.

PREFERRED SIDE OF BENDING
The center of the upper and lower teeth doesn’t match. The lower jaw (mandible) is offset to the right. This follows the pattern of a left dominant horse, in which case the horse prefers to shift more weight over the left front shoulder/leg, causing a slight bend through the body to the right.
Oftentimes these horses have an easier canter lead going right and a lower hoof on the right front. The teeth often have more wear on the right side (creating a diagonal right, as in this horse). This all follows the compensatory pattern of a left dominant horse (=preferring to bend right).

02/06/2025

UPDATED SCHEDULE

If you see your area on the schedule, but haven't received a message yet, I very much welcome a reminder. Thank you 😊

SOUTH CAROLINA
June 9-10: Aiken
June 11: Aiken, Chapin

NORTH CAROLINA
June 12-13: Columbus

SOUTH CAROLINA
June 14: Inman
June 15: Aiken

VIRGINIA
June 17-19: Chincoteague

MASSACHUSETTS
June 21-23: Bedford
June 24: Hubbardston

PENNSYLVANIA
June 25: Kennett Square

MARYLAND
June 26: Churchville

VIRGINIA
June 27: Dublin

SOUTH CAROLINA
June 28: Aiken

GEORGIA
June 29: Ellabel
June 30-July 1: Rincon, Beaufort

SOUTH CAROLINA
July 2: Aiken

COLORADO
July 4-5: Denver/Boulder

CALIFORNIA
July 7: Menifee
July 8: Temecula
July 9: Bonsall, Murietta
July 10-11: Hidden Valley
July 14: Ojai
July 15: Rancho Santa Fe
July 16: Burbank
July 17: Arroyo Grande
July 18: Atascadero, Templeton
July 19-25: South and North Bay (currently working on schedule)
July 29-August 1: Arroyo Grande
August 4-5: Los Angeles

IDAHO
August 6-10

CALIFORNIA
August 11: Orange County
August 12-13: Ramona
August 14: Poway, Lemon Grove
August 15: Escondido
August 18-19: Los Angeles

COLORADO
August 20-24: Denver, Boulder

Working on the rest of the schedule

FLORIDA
September 5-8: West Palm Beach

SOUTH CAROLINA
September 10-12: Aiken

COLORADO
September 18-21: Denver/Boulder

17/05/2025

Heartbreaking news from the conservancy we stayed at in Zimbabwe. The Travers family and their team work 24/7 to protect this species from going extinct. It was incredible to see the amount of work and dedication that goes into conservation and an incident like this is devastating for everyone involved. These animals are jaw dropping beautiful creatures and need to be protected. On a positive note, they had three rhino babies born in one week. The highs and lows of conservation work.

Imire Rhino and Wildlife Conservation Security Fundraiser

10/05/2025

TEFF HAY SEED HEADS
Watch out!

This extensive damage to the gums was created by Teff hay seed heads.
The seed heads act like little hooks and get stuck underneath the gums causing inflammation and lacerations. Even the slightest touch of the gums makes them bleed, creating small wounds for bacteria to enter and fester.
This horse was showing a lot of discomfort and pain symptoms.

Teff is a great hay, but make sure to look for first cut, before it has gone to seed. Second and third cut will have seed heads and the later cut, the more seed heads it will have.

26/04/2025

CASE STUDY OF THE MONTH

Because many people ask,
‘WHAT IS OSTEOPATHY AND WHAT DOES AN OSTEOPATH DO?’,
I started a (bi-) monthly case study series to illustrate how it works and what it could do from the perspective of a WHOLE HORSE approach.

CASE STUDY #2, MOOSE

During our trip in Oregon, earlier this month, Rachel Ashworth (equine osteopath) and I saw Moose for the third time. We had worked with him twice before and had found some important puzzle pieces in understanding his situation.

The first time we saw him together was in March 2024 (Rachel had seen him before and put him on the list for a combined visit). He was a 14yr old Tennessee Walker gelding, owned by Erica for the past 2 ½ yrs. He came with the history of flipping over once in the cross ties when he was young, causing a neck injury. This led to a fused C2-C3 (2nd and 3rd neck vertebrae). Other than that, he had no known issues.

Erica purchased him for trail riding. He had a very sweet and willing demeanor, but was extremely tense under saddle. He tripped on the right front when ridden and would often blow up, trying to convince the rider to get off.

Upon checking his body and teeth, something felt very off. His innate pattern of a right dominant horse was clearly visible in his front feet, base of the neck, shoulder blades and incisors (front teeth). These areas of compensation were all matching and in line with each other, it made sense, no problem there.
But there was a different pattern as well and this one did not make sense initially. What was going on here? Why had the body created this different compensation pattern?

Looking at his face straight on, it was bend to the right, like a banana, and rotated right, with his right nostril higher than the left and his right eye socket rotated right. His right TMJ and temporal bone were not moving in any way and felt ‘dented in’. His incisors (front teeth) had a slight slant, which matched his innate pattern, nothing remarkable there, but his molars were a different story. The left side of his mouth was pretty normal. But his right lower molars were enormous, twice as high as the left side. This was a mystery. What was causing these teeth to erupt so much more than the rest of the mouth? Or maybe they were not wearing down enough? We recommended x-rays of his skull, TMJ’s and teeth to hopefully get some answers.

Based on the x-rays, the vet diagnosed him with arthritis in the right TMJ. An osteopath looks at x-rays as well, not to diagnose pathology (that’s the expertise of the vet), but to look at joint positions and opening/exit spaces for nerves and circulation (blood vessels and lymph) to understand possible issues in fluid flow and nerve signaling.

Looking at the x-rays from osteopathic perspective, it showed the joint in the center of his skull (SSB) had shifted. This joint isn’t fused yet in young horses and is therefore movable, for example with an impact on the skull. This made us believe it had most likely happened at the time he flipped over in the cross ties when he was young. The direction of the shift correlated with the bend in his face (the sphenoid determines the position of the upper jaw/maxilla) and the ‘dented in’ position of the right temporal bone and TMJ. Over time, this might have caused the TMJ arthritis which was diagnosed by the vet.

It also showed the opening space for some important cranial nerves to be almost closed, due to this shifted bone. One of the nerves running through this space is the Trigeminal nerve-the mandibular branch. This branch innervates the right lower jaw and right lower teeth. Our take on these enormous lower molars was now twofold; due to the shift in the upper jaw, top and bottom molars weren’t matching anymore, causing them not to wear down. At the same time, an irritation/overactivation on the Trigeminal nerve was possibly causing these lower teeth to erupt much faster than usual.

The Trigeminal nerve also innervates the sheath around the brain and the spinal cord (dura mater). When overly activated, this sheath tightens, resulting in tension on the brain and entire spinal cord; like a jacket that is too tight and limits movement. This was most likely aggravated with a rider on his back, resulting in his behavior to try and get the person off.

All these changes and tension on the right side of his head, brain and spinal cord have an effect on his proprioception as well (knowing where your body parts are in relation to each other and space) and most likely the cause of his tripping on the right front leg.

We now had a better understanding of his body and behavior, but also realized no major changes were possible. What was created by the body as a result of the impact at a young age, needed to be respected. We worked with him from that perspective, trying to alleviate as much tension as possible.
Since then, Erica has retired him from riding. He enjoys hanging out in the herd and being ponied on the trails with his buddies.

Sometimes the best way to help, is to help find answers.
Osteopathy could be a part of the collaborative effort in figuring out the puzzle.

19/04/2025

WHEN AND HOW DOES A SLANT IN THE INCISORS (FRONT TEETH) SEEM TO DEVELOP?
(case study findings)

The large majority of horses develop a slant/wedge in the incisors (front teeth) due to functional use. The way the horse balances and uses its body (function) seems to shape the form (direction of incisors).

This is one of the findings in collaboration with several osteopaths over the past 3 years. it’s been very interesting to see what appears to be a strong correlation between the direction of the slant and the direction of the base of the neck, in particular C5-C7, with C7 (the lowest part) as the dominant one. The preferred side of bending seems to correlate with the bending in the neck and the preferred side of chewing. Interestingly, by releasing the base of the neck yearly, a corrected slant doesn’t seem to re-develop again in many cases.

It’s very rare to see a young horse (younger than 3 yrs old) with a slant. This is frequently due to truly anatomical changes in the skull and mouth (for example a birth defect or trauma at young age).
The majority of slants in young horses are due to functional use of the body and are just starting to develop; the horse is young and hasn’t had many years of using the body yet in its preferred pattern. Many dentists and practitioners do not work with the incisors and in particular not in young horses. I do believe this is a greatly missed opportunity with lifelong consequences for the horse’s balance and movement.

Some of these slants start developing around as young as 4-5 years old. It starts with just 1 or 2 degrees and will develop into a larger slant when the horse gets older. At this age and with such a minor slant, a correction is very easy; 1-2 degrees can often be corrected in one dental session and the body is still very young and pliable to adapt. A 15 yrs old horse with a 6 degrees slant and many years of using the body in this pattern will be more challenging to work with and needs multiple sessions to get back to a more balanced mouth and body, if at all possible.

The main issue with a slant is the deviation of the mandible (lower jaw). A slant to the left causes the mandible to deviate left, a right slant causes right deviation. The direction of the mandible is one of the most determining factors in the balance and movement of the entire body. Explanation of how this works would be too elaborate for this post, but might be a topic of a future one.
Therefore, leaving a slant in a young horse to develop into a larger one over the years is setting the horse up for limitations. Working with the slant (and the base of the neck) as soon as it develops, provides the chance to move and develop as balanced as possible throughout its life.

Attention to the incisors of young horses would have long-lasting effects for the functioning of the WHOLE HORSE throughout its WHOLE LIFE.

08/04/2025

Another great trip in Oregon, with equine osteopath, Rachel Ashworth from Balancing Point. A nice mix of new and returning horses, making a total of 65 horses seen. So many interesting connections between teeth, body and feet to go over, feel, discuss, validate or not validate. As always, these collaborations are invaluable for further progress and learning. So much fun!
This picture is the last horse on the last evening of the trip and we were still as happy working with her as with the first one! We’ll do it again in the fall 😁
Rachel works and travels in Oregon. She can be reached through her page

https://www.facebook.com/BalancingPointEquineBodyWork?mibextid=wwXIfr&mibextid=wwXIfr

22/03/2025

A great trip through California and Nevada! Summer temperatures in the south and snow storms in the north, all possible in March. Highlight of the trip was meeting up with equine osteopath EDO Fenja Koningsmann in the Shasta area! Those days of collaboration are invaluable. Feeling horses, discussing cases, sharing ideas and experiences and supporting each other. We hope to do it for many more years.
Fenja travels/works in the Bay Area, Northern California, Nevada, Oregon and Oklahoma. She could be contacted through her page,

https://www.facebook.com/flowingwaterswholistics?mibextid=wwXIfr&mibextid=wwXIfr

13/03/2025

This is a coming 5yr old. All permanent teeth are in and in occlusion (in contact with the opposing one). It’s subtle, but it’s starting to be visible in the teeth;

Which side does this horse prefers to bend to?
Which side of the neck will be more stiff?
Which front hoof will be (or develop into) the lower one?
Which side will he fall into the circle?

UPDATED:

Thank you to everyone who responded! Here are the answers and explanation.

Which side does this horse prefers to bend to?
RIGHT
Which side of the neck will be more stiff?
LEFT
Which front hoof will be (or develop into) the lower one?
RIGHT
Which side will he fall into the circle?
LEFT
(all was confirmed by the owner)

This is a healthy, thriving young horse using his body according to his innate pattern. Like humans, horses are born left or right side dominant and will therefore use their body accordingly (in movement and holding pattern). Left and right side will not be symmetrical due to differences in use. For example, a right-handed person will be stronger in the right arm compared to the left, due to using the arm more. This sidedness will work through the whole body creating a preferred side of bending and use of the legs. Same for horses. This is an innate pattern and it’s normal.

Using the body in a preferred way will eventually show signs in the body. The front teeth (incisors) are one of the areas where this can become visible.
The most important sign in the front teeth is the position of the mandible (lower jaw).
The body creates the offset of the mandible due to preferred use and will follow the direction of the mandible.

In short: THE BODY FOLLOWS THE DIRECTION OF THE MANDIBLE.

A mandible offset to the right, means the body prefers to bend RIGHT.
The neck will bend easier to the right and will be more stiff to the LEFT.
This is due to the innate pattern of the horse being left dominant, shifting more weight on the left front foot and therefore bending easier to the right. These horses often prefer to graze with their RIGHT front foot forward and this hoof will therefore become lower due to more pressure on the heel.
Putting more weight on the left front leg makes the horse fall into the circle going LEFT.

NOTE: trauma (impact) and overload (overuse) can cause the body to be adapt in a way different from the innate pattern.

05/03/2025

UPDATED SCHEDULE

If you see your area on the schedule, but haven't received a message yet, I very much welcome a reminder. Thank you.

New state has been added to the travel schedule;
COLORADO

CALIFORNIA, NEVADA
March 6: Hanford
March 7: Briones
March 8: Petaluma
March 9: Nicasio, Santa Rosa
March 10: Loomis, Orangevale
March 11: Citrus Heights, Penryn, Newcastle
March 12-15: Mt. Shasta area
March 16: Janesville
March 17: Janesville, Reno
March 18-19: Reno
March 20: Fresno
March 21: Topanga
March 22: Ojai, Santa Paula
March 24: Lakewood
March 25: Sun Valley

OREGON:
March 26 - Apr. 6

CALIFORNIA:
Apr. 8: Menifee
Apr. 9: Hidden Valley
Apr. 10: Sylmar
Apr. 15: Bonsall
Apr. 16-18: Riverside
Apr. 21-26: Arroyo Grande
Apr. 28: Menifee
May 1: Santa Barbara
May 2: Hidden Valley, Moorpark

COLORADO:
May 5-8: Denver, Boulder

CALIFORNIA:
May 9: Topanga
May 12-13: Los Angeles
May 14-19: Watsonville, Gilroy
May 20-23: Gilroy

SOUTH CAROLINA/NORTH CAROLINA:
May 26-28: Aiken
June 9-10: Aiken
June 11: Chapin
June 12-15: Inman, Landrum, Columbus, Asheville

Currently working on the rest of the schedule, but here's the outline.

VIRGINIA:
June 16-20

MASSACHUSETTS:
June 21-24

MARYLAND, VIRGINIA, NORTH CAROLINA
June 25-30

GEORGIA:
July 1-3

COLORADO:
July

CALIFORNIA:
July - August

COLORADO:
August

01/03/2025

CASE STUDY OF THE MONTH

Because many people ask,
‘WHAT IS OSTEOPATHY AND WHAT DOES AN OSTEOPATH DO?’,
I thought it might be interesting to start a (bi-) monthly case study series to illustrate how it works and what it could do from the perspective of a WHOLE HORSE approach.

This first case study is not from this past month, but from 5 years ago. It’s such a great case and highlights wonderfully how osteopathy can compliment other equine healthcare modalities.

Murielle Richard-Price, a student in equine osteopathy school, and I had planned a work trip for two weeks in the Bay Area in California. The schedule was full and we had a waiting list of a few horses. A week before the start of the trip, Murielle received a request from Masterson Method Practitioner, Sandy Vreeburg, if we could please visit this one horse she was working with, hoping osteopathy might shed some light on his situation. The schedule was full, but when we heard the story, and received a desperate email from the owner as well, we understood the situation was pretty dire and made changes to accommodate a visit.

Avanti was a 15yr old Dutch Warmblood owned by 14yr old Rachel and her mom April. Rachel and Avanti rode through a gate one day when the stirrup got stuck on the gate, pulling the saddle off to the side. Rachel came off, Avanti spooked and ran off bucking with the saddle on his side, eventually stopping with it hanging on his belly. Both were shaken up, but seemed ok. The vet came out to give him a check over and concluded he was ok.

Pretty soon after, Avanti colicked and this was followed by many more colic episodes and hospitalizations over the next two months. His stomach would get very bloated and he wouldn’t eat. He was scoped multiple times combined with abdominal ultrasounds, but no answers. He was in and out of the hospital constantly and was prescribed a diet of senior feed only, with the belief he would never eat hay again. After another 10 days in the hospital, the recommendation was given to do exploratory abdominal surgery.
We visited Avanti a few days after this last hospital stay. The hope was to find clues as to why his body was having this continuous digestive upset.

Osteopathy works from the knowledge that every structure and tissue in the body needs to be mobile to function properly. Nothing in the body is static; bones, joints, muscles, tendons, ligaments, nerves, blood vessels, lymph vessels, teeth, hooves, fascia and organs are mobile.
Immobility causes disturbance in the function of the structure/tissue, making it susceptible for issues/disease/trauma. An osteopath assesses and works with mobility of these structures/tissues, and with a strong knowledge base in anatomy/physiology, tries to find the root cause of issues.

Avanti had many restrictions; structures/tissues which did not move properly. This was to be expected after the incident of bucking around with the saddle on his side, but also the multiple colics and scoping. My hands were feeling and my brain was working. Which structures were not moving and where in the body was this going to cause problems?
Often times the symptom is not where the cause is. Also for Aavanti.

Any of the restrictions he had, could have caused his problems to some degree, but it wasn’t IT. What was it specifically in him that caused this bloating of his stomach?
When I got to his left rib cage to check the movement of his ribs, he had a couple of restricted ribs in the girth area. Very common, nothing unusual. I continued feeling the rest of the ribs and felt rib 13 and 14 were not moving. This is unusual. I rechecked and rechecked, definitely not moving. That was IT, the ROOT CAUSE! These two ribs were the cause of this whole digestive ordeal he had been in by causing a spasm on the pylorus of the stomach.
What does this mean and how do we know?

Rib 13 and 14 are attaching to the spine at the 13th and 14th vertebrae. If these ribs are not moving, they will hold the vertebrae in a restriction as well. These ribs were on the left side. The nerves coming out of the spine at the 13th and 14th area innervate the stomach, which is also situated on the left side of the body. They specifically innervate the pylorus of the stomach, which is the exit. These nerves can get irritated when the vertebrae don’t move properly. They can start firing too much causing overload of signals to the tissues they innervate, in this case the exit of the stomach. This high firing of signals caused the exit of the stomach to contract too much, causing a spasm, limiting the opening of this exit muscle (pylorus), causing retention of food and distention of the stomach and causing the colics
The root cause of these colics were these two, non-moving, ribs and not the stomach or anything in the digestive system itself.

The ribs were released, along with other restrictions in the body. Due to the many colics and the downward spiral he had been in, his system was very fragile and rehab had to be done very carefully as to not set off his nervous and digestive system again. Weekly emailing with Rachel and April, on how he was doing and how to proceed further, continued for months. After 6 months they were back to riding and he was back on an all-hay diet.
A great outcome for Avanti! And the best part of all, Rachel is now 18 years old and determined to become an equine osteopath!

Picture 1: Avanti in July 2024, 5 years later
Pivture 2: Rachel practicing osteopathy with Avanti