Jo Johnson Equine Physiotherapy

12/04/2026

The Lumbosacral Joint (L6–S1): The "Hinge of Power"

The lumbosacral junction (L6–S1) is one of the most important power-transfer points in the horse’s body. It’s where the final lumbar vertebra meets the front of the sacrum— a bridge between the "engine" (the hindquarters) and the "chassis" (the spine).
The lumbosacral (LS) joint acts as a hinge that allows the pelvis to rotate and the hindlimbs to generate propulsion.

Most horses have 6 lumbar vertebrae (L6), but many (especially Arabians and some Thoroughbreds) have 5 (L5).

The LS joint is designed for flexion far more than extension. While some extension occurs, excess is usually protective, compensatory, or pathological.

Pain can originate from the disc (rare) or the facet joints associated with the joint (common in jumpers and dressage horses due to repetitive loading at the end of the range of motion).

High-level collection requires the horse to hold a degree of LS flexion while the limbs extend. If the horse cannot maintain this "abdominal lift” they drop the back, leading to rotation of the pelvis and high-impact loading on the facet joints.

The LS joint is usually the victim of dysfunction elsewhere.

1️⃣ Shock Absorption
If a horse has hock or stifle pain, they lose their ability to use the hind limb as a shock absorber. Instead of the leg "compressing" like a spring, the force is directed into the LS joint. This creates great tension in the Longissimus as the horse tries to "brace" the spine against the impact. Assessing the whole horse is so important.

2️⃣ Proprioception
The LS region is rich in proprioceptors.
When this joint is stiff:
The horse loses awareness of where its hind feet are (proprioceptive deficit).
This leads to "tripping," "forging," or an irregular rhythm in the canter.

3️⃣ The Psoas-LS Connection
The Iliopsoas muscle group sits directly beneath the LS joint. Chronic LS tension often leads to Psoas spasm- which shortens the swing of the hind leg. The horse literally cannot reach forward with their hind feet.

Clinical Indicators for the Physio

Difficulty or "swapping" in one canter lead often indicates an asymmetrical restriction in the LS/SIJ.

The "Tail Guard" Sensitivity: Horses with LS/SI discomfort are often hyper-sensitive around the dock or resent having their tail handled or wrapped.

The "Square Halt" Test: A horse unable to flex the LS joint will almost always halt "camped out" (hind legs left behind the body) because "tucking" the pelvis to square up is uncomfortable.

A "hard" back isn't a strong back. Hypertonicity (protective guarding) and Core Engagement are not the same. True stability comes from the Multifidus and Abdominals, not the Longissimus.

If the LS joint is hypomobile (stiff), the horse will often try to create movement at the T18–L1 junction instead. This leads to "dipping" behind the saddle.

Proprioceptive Retraining
Standard "straight line" walking isn't enough. Use varied terrain (poles, uneven ground, and reflex exercises) to "re-map" the brain's connection to the LS joint.

📚References

Gellman, K., & Shoemaker, J. (2012). Equine Evolution and Anatomy. (Focuses on L5 vs L6 variations).

Denoix, J-M. (2021). Biomechanics of Lameness in Horses. (The definitive guide on how distal limb pain reflects in the LS joint).

Zaneb, H., et al. (2009). Effects of specific compensatory patterns on the equine sacroiliac and lumbosacral regions.

09/04/2026

Pole Work: Why It’s So Powerful (and Why Less Is More)

Pole work is far more valuable than perhaps is realised. Involving the central nervous system and requiring precise limb coordination, pole work is a highly demanding neuromuscular task that challenges the horse’s body and brain at the same time.

Pole work is excellent for:
• Proprioception
• Rehab & Pre-hab
• Strengthening propulsive muscles
• Improving joint range of motion (ROM)
• Postural and spinal stability

Horses cannot see their feet near the pole, so they rely on visual proprioception as they approach- meaning accuracy comes from neurological control, not eyesight.

And don’t just watch the swinging limb — the stance limb is doing the real work. The limb in stance provides trunk stability while the opposite limb clears the pole.

I.e- If you want to strengthen the right hind, you can raise the pole on the left side, increasing weight-bearing time on the right.

Ground poles
• Greatest flexion occurs at the fetlock
• Improves ROM at fetlock, carpus/hock, elbow/stifle
• Effective in walk and trot

Raised poles
• Increase flexion further
• Increase body sway as the trunk stabilises mediolaterally
• Significantly more demanding — use sparingly

If in doubt: start with poles placed on the ground. The spacing for walk poles should be slightly shorter than the horse’s usual walk stride. No need to rush the horse, there is greater benefit from going slow.

Research shows pole work:
• Improves joint ROM without significantly increasing ground reaction forces
• Encourages spinal stabilisation, not excessive movement
• Activates the multifidus (a key deep stabiliser that anticipates movement before it happens)

Studies by Dr Russell McKechnie-Guire and Dr Narelle Stubbs show that:

• Pole work and dynamic stability (baited stretches) exercises both increase multifidus cross-sectional area
• Longissimus activity does not significantly change
• A combined approach is highly effective for posture and spinal support

Pole work is hard work. Signs of fatigue:

• Knocking poles
• Loss of rhythm
• Reduced accuracy

If you hear poles being hit, stop — that’s a strong fatigue marker. Always monitor the horse’s capacity.

In-Hand vs Ridden

• In-hand pole work is invaluable — so much so that Dr Russell McKechnie-Guire states he would often choose it over a ridden session
• With a rider, biomechanical demands increase significantly
• Rider weight is magnified through the spine (≈2× in walk, 2.5× in canter)
• Rising trot introduces asymmetry; light seat is more symmetrical and lower pressure

Long ridden pole clinics correlate with increasing fatigue and pole taps — something to be very mindful of.

🟢 Practical Take-Home

• Present straight to the poles
• Use shorter distances (~85% of step length) for better spinal stability
• Walk slowly for best results
• Start with ground poles before raised poles
• Progress by:
– Increasing number of poles
– Raising poles
– Altering spacing (irregular patterns)
🟩 Slow. Low. Short.

Pole work is incredibly valuable — when used thoughtfully.

06/04/2026

OA MYTHS

Myth 1: “Arthritis is just wear and tear”

Reality:
Osteoarthritis is a whole-joint inflammatory disease, not just worn cartilage.
Synovium, bone, capsule, ligaments, and muscles are all involved.

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Myth 2: “If the X-rays look bad, the horse must be in pain”

Reality:
Pain and imaging don’t always correlate.
Some horses with severe radiographic changes cope well, while others with mild changes are very uncomfortable.

Function and movement matter.

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Myth 3: “Cartilage damage is where the pain comes from”

Reality:
Cartilage has no nerve supply.
Pain mainly arises from:
• Inflamed synovium
• Subchondral bone
• Joint capsule and surrounding tissues

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Myth 4: “Arthritis only affects old horses”

Reality:
OA can develop in young horses, especially following:
• Developmental issues
• Poor biomechanics
• Repetitive overload
• Previous injury

Age may accelerate OA but doesn’t cause it.

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Myth 5: “If a horse isn’t lame, they don’t have arthritis”

Reality:
Horses are masters of compensation.
OA often presents as:
• Stiffness
• Shortened stride
• Reduced impulsion
• Behavioural or performance changes

Not all arthritis looks like lameness.

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Myth 6: “Once a horse has arthritis, they should be rested”

Reality:
Prolonged rest often worsens stiffness and weakness.
Controlled, appropriate movement:
✔ Nourishes cartilage
✔ Maintains range of motion
✔ Supports joint stability

Movement is medicine — when dosed correctly.

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Myth 7: “Joint injections fix arthritis”

Reality:
Injections (e.g. corticosteroids, hyaluronic acid, orthobiologics) help manage pain and inflammation, but they don’t:
• Reverse joint changes
• Correct movement patterns
• Restore strength

Other veterinary treatments (e.g. NSAIDs, systemic therapies) can also help — but long-term outcomes depend on how the joint is loaded and supported.

Best results come from combining veterinary treatment, physiotherapy and appropriate modified exercise.

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Myth 8: “Supplements will cure arthritis”

Reality:
Some supplements may help support joint health, but evidence varies.
They are adjuncts, not stand-alone treatment.

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Myth 9: “Arthritis is always progressive and untreatable”

Reality:
While OA can’t be cured, progression can often be slowed.
Early identification, good biomechanics, and appropriate management can maintain comfort and function for years.

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Myth 10: “Arthritis only affects lower limb joints”

Reality:
OA commonly affects:
• Neck joints
• Sacroiliac region
• Stifles
• Facet joints

These often present as poor performance or behavioural issues, not obvious lameness.

03/04/2026

🐎 The Biomechanics of the Trot — What’s Really Happening

The trot is more than just a two-beat gait — it’s a finely tuned spring system.

✨Here’s what your horse’s body is doing:

• Each stride generates 1.5× the horse’s bodyweight in ground reaction force.

• A moment of suspension lets tendons, ligaments & fascia stretch and recoil, creating free energy and propulsion.

• Even diagonal footfalls with a regular, rhythmic cadence.
• Subtle head lift in suspension; slight lowering as the forelimb makes contact (in a sound horse).

• A telescoping, forward-reaching neck allows more hip extension and a longer stride.
• A retracted neck shortens the stride and is typical in collection.

• The trot is the most stable gait for the spine.

• Small lateral bends occur around T9–T10 and T14–T15.

• Most flexion happens near the thoracolumbar junction (T17–L1).

• Rotation is minimal (~1°).

• The biceps catapult provides ~80% of shoulder extension — powering the forward swing.

• The retraction chain (triceps, SDFT, fascia, etc.) drives the push-off.

✨ Lameness Clues
• Forelimb: head lifts on the lame side.
• Hindlimb: tuber sacrale rises on the lame side.
• Swing-phase issues: reduced protraction, toe drag, low arc.

✨ Training Tip
Trot poles encourage mobility, stride length, and improved symmetry.

31/03/2026

💦 Before you put a horse on a water treadmill… ask why.

At the recent Horses Inside Out Conference, Dr Kathryn Nankervis, Director of the Equine Therapy Centre at Hartpury University, highlighted the importance of understanding the purpose behind using a water treadmill.

Common reasons for use:

•Training tool – improve function or performance: Encourages active limb retraction, strengthens hindlimbs and core, without hard-ground impact.

• Cross-training – add variety: Changes sensory input and movement patterns, reduces repetitive strain, and keeps horses mentally and physically fresh.

• Rehabilitation – controlled recovery: Adjustable water depth reduces impact and supports joints, allowing gradual, safe reintroduction of movement while protecting healing tissues.

How it works:
The moving belt encourages limb retraction during stance, while water resistance increases joint range of motion.

Water depth matters:
• Low water – supports the back and improves postural stability
• High water – increases movement in proximal joints and can help build hindlimb muscle mass (but not ideal for horses with back pain or kissing spines due to increased extension of back)

Perceived benefits:
• Improved hindlimb strength
• Enhanced postural control

❌Not Every Injury Belongs on a Treadmill:
While water treadmills can be valuable tools, they are not always appropriate—particularly for horses with tendon or suspensory ligament injuries. The moving belt encourages limb retraction during stance and alters normal loading patterns, which can increase tensile strain through the superficial and deep digital flexor tendons and the suspensory apparatus. Water resistance also prolongs the stance phase and increases time under load, potentially stressing healing fibres before they are ready to tolerate it. In early or poorly progressed rehabilitation, this can risk delayed healing, fibre disruption, or re-injury. For these cases, controlled straight-line exercise on a stable surface is often more appropriate until sufficient tissue strength and load tolerance have been restored.

Takeaway:
Water treadmills aren’t one-size-fits-all. Match the water depth and protocol to the horse, the goal, and the back or tendon and ligament health—whether you’re rehabbing, training, or adding variety.

💦 See the link below for an owner friendly guide to treadmill use 💦

https://www.britishequestrian.org.uk/assets/NEWS/HPY_WT_DOC_APRIL2020_RELEASE%20(003).pdf

28/03/2026

Recognising a Left-Sided Pelvic Shift in Riders

As a physio, I’m endlessly fascinated by the biomechanics of horse and rider. As a rider who personally tends to collapse through the right side of my rib cage, I’m very aware of the knock-on effects this pattern can create in the saddle.

One of the most common postural asymmetries I see in riders is a right rib-cage collapse with a subsequent leftward pelvic shift. This pattern often shows up through the following riding issues:

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🚩 Common Signs

• Foot tension in the stirrup
Gripping through the foot can cause supination, the knee drifting away from the saddle, external rotation and shortening at the hip, torso shortening on the same side, and the seat bone slipping out from underneath the rider.

• Right leg lifting or loss of the right stirrup
With the pelvis habitually shifted left, riders often struggle to fully weight-bear on the right side.

• Difficulty riding to the right
Right-rein work frequently feels more challenging than left-rein work.

• Over-reliance on the right rein
Gripping the right rein while neglecting the left is often a compensation for pelvic instability.

• Left hand carried higher than the right
A subtle but common indicator of a left-shifted pelvis.

• Comfort cantering anti-clockwise, discomfort clockwise
Right-lead canter or clockwise work is often significantly harder.

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🎯 What Needs Addressing?

The primary issue is usually one of the following:
• Re-centralising the pelvis
• Restoring balanced foot contact in the stirrup

The secondary signs—right rib-cage collapse, right leg elevation, uneven rein contact—are compensations. Address the primary issue and these often resolve without additional cues.

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🗣 Clear & Effective Cues

• “Bring your left seat bone back toward the centre of the saddle, and allow your right seat bone to soften and drop into the space that creates.”

Or:
• “Release the inner thigh of the right leg and allow the leg to lengthen, with the toes softly spread.”

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🏋️‍♀️ Corrective Exercises

1️⃣ Right-side loading (trot)
On a clockwise track, remove the left stirrup and rise using only the right stirrup. Very challenging—but very effective.

2️⃣ Thoracic rotation to assist weight shift
If a rider persistently drifts left, a slight leftward rotation of the chest while travelling right can help load the right leg.
We naturally shift weight into the opposite limb when rotating through the thorax.
Think: lift through the right rib cage while gently turning the shoulders left.
Practise this in standing first.

3️⃣ Gluteus medius strength
Weakness in the left gluteus medius often contributes to this pattern and may be reinforced by horse-related asymmetry.
Test: stand on one leg facing a mirror—if the pelvis shifts laterally, control is reduced.
Side-lying leg lifts are a good starting exercise.

4️⃣ If toe-curling is the main issue
Toe spreaders can help reduce gripping and restore more balanced foot contact.

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🐎 How This Affects Your Horse

Your horse feels a left-shifted pelvis immediately.

• Falling in on the left rein and drifting out on the right
• The right hind trailing rather than stepping under
• Difficulty turning right or striking off on the correct lead—not from resistance, but from conflicting weight signals

To stabilise, riders often pull on the right rein, creating neck tension and limiting freedom through the horse’s body.

When the pelvis returns to centre, rhythm steadies, the shoulders free up, and overall balance improves.

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Although I no longer treat people, my background in human biomechanics allows me to recognise rider asymmetries and understand how they influence the horse. These patterns strongly inform my assessment and treatment of the horse’s musculoskeletal system.

25/03/2026

Lateral Saddle Slip: It’s (Usually) the Horse — Not the Rider

Saddle slip is far more common than most riders realise — and it’s also one of the most misunderstood saddle fit issues we see.

Research suggests that 60–70% of horses show some degree of lateral saddle slip, yet it often goes unnoticed until a saddle fitting, physio or vet visit highlights it. And despite popular belief, saddle slip is rarely caused by the rider.

Evidence consistently shows that saddle slip is horse-driven, not rider-driven. Riders may influence how obvious it becomes, but they are very rarely the root cause.

Why does it matter?
A subtly slipping saddle can:
• Pull the rider’s pelvis to one side
• Make one leg feel longer than the other
• Create a “crooked rider” appearance
• Lead to endless rider exercises that never quite fix the problem

If a saddle slips to the right, for example, it’s often most obvious on the left rein, while appearing straight on the right — which makes it even harder to spot.

What’s really going on underneath?
In most cases, the saddle slips towards the weaker hind limb. This is rarely a forelimb issue and is commonly linked to:

• Hind limb weakness or asymmetry
• Sacroiliac dysfunction
• Stifle or suspensory issues
• Kissing spines
• Foot balance problems
• Ulcers
• Weakness in young horses or arthritis in older horses

Of course, the saddle slip can be more pronounced or better disguised— depending on the rider’s own symmetry, strength, balance and expertise

Left unaddressed, both horse and rider adapt — often unknowingly — which can compromise muscle development, symmetry and long-term soundness.

Why qualified saddle fitting matters
Correcting saddle slip properly requires a dynamic saddle fit, meaning the horse must be seen ridden. A Society of Master Saddlers Qualified & Registered Saddle Fitter is trained to assess lateral stability from behind, in front and from the side — not just static fit.

Modern saddles allow adjustments through:
• Flocking
• Shims
• Girthing configuration
• Tree width
• Or a combination of all four

The goal is always the same: get the saddle straight. Leaving it slipping is not an option.

Teamwork is essential
While saddle fitters can correct the symptom, identifying the cause requires collaboration with vets, physios and farriers. Straightening the saddle often allows the horse to finally strengthen — something that simply isn’t possible when uneven loading continues.

Regular reviews matter
As the horse changes (hopefully becoming stronger and more symmetrical), the saddle must change too. This is why qualified saddle fitters take templates and detailed records — what works today may not work in six weeks’ time.

Key takeaway:
Saddle slip is very rarely caused by the saddle itself. If it were, it would slip both ways. The evidence overwhelmingly points to the horse being the primary driver.

When we address saddle slip early and correctly, we’re not just straightening a saddle, we’re protecting soundness, symmetry and long-term equine welfare.

21/03/2026

Equine C6–C7 (and Rib) Morphological Variations: Management Matters

Some horses are born with structural variations around the C6–C7 vertebrae and ribs. These changes are not always obvious, but they can have significant effects on comfort, coordination, and behaviour.

🔍 Diagnosis
CT scanning is the gold standard. This area (the cervico-thoracic junction) is particularly vulnerable, especially in ridden horses where certain neck positions can increase compression.

🦴 What might we see?
• Asymmetry due to extra (cranial) ribs or sternal changes
• Muscle asymmetry in the neck
• Head tilt with one-sided (unilateral) malformations
• Narrowing around the spinal cord, affecting coordination and gait

❓Why it matters
These horses often have a highly sensitised nervous system. This can influence:
• Balance and limb loading
• Gait coordination or ataxia
• Secondary issues elsewhere in the body (even the feet)

🐴Management is critical
Because the nervous system is easily overwhelmed. Strong advice includes:
• Keeping routines consistent
• Handle calmly and predictably
• Expect higher reactivity

🤲🏼Treatment & rehab: proceed with caution
• Pain relief can sometimes reduce stability in the forelimbs
• Bodywork may undo compensations the horse is relying on
• Exercise selection is tricky

⚠️ Be careful if you suspect this condition in your horse.
• Poles may not be appropriate
• Avoid unstable surfaces
• Rehab must be individualised and conservative

These horses need thoughtful, informed management rather than “more work” or generic exercises.

18/03/2026

Back pain in horses isn’t always obvious on X-rays or scans. Even when imaging looks normal, movement and performance can be affected.

Functional assessment matters – observing your horse, feeling for muscle tension, and testing movement can reveal subtle issues.

Deep stabilisers like the multifidus support the spine but if these weaken, other muscles overcompensate, causing more pain.

Targeted exercises can help – backward walking, hill work, pole exercises, and specific stretches to reactivate stabilising muscles and improve coordination.

Research shows that medication alone or local therapies can help, but it is exercise that retrains the spine for long-term stability and comfort.

Pain relief + exercise = best results

Prevention counts too – exercises aren’t just rehab—they help keep healthy horses strong and resilient.

Strong, balanced muscles enable happy, comfortable movement.

14/03/2026

🏇 Rider Balance Matters—For You and Your Horse

At the recent Horses Inside Out Conference, Dr Lee Clark examined rider balance and its interaction with equine laterality.

He demonstrated the complexity of how rider balance and body asymmetry interact with a horse’s natural laterality. Riding often uncovers patterns, like waist collapse or trunk rotation—that aren’t obvious off the horse or on simulators.

Trunk asymmetries are linked to hip rotation limits and abductor strength, and even everyday stable tasks - like mucking out or sweeping—can reinforce these imbalances over time.

And it’s not just riding and horse related tasks that matter. Everyday movements—how you sit in the car, how you sleep, can subtly reinforce these patterns over time.

Being aware of your own symmetry, posture, and strength directly affects how your horse moves, engages, and performs.

11/03/2026

Sure-Foot proprioceptive pads- a tool to help horses improve coordination, stability, and confidence in movement.

What they do:
These pads gently challenge a horse’s balance, stimulating muscles and nerves to improve posture, core strength, and proprioception (the body’s awareness in space). Perfect for strengthening weak areas or aiding rehabilitation after injury.

Benefits:
• Encourages proper weight distribution
• Activates stabilising muscles in limbs and core
• Improves confidence over uneven or unfamiliar surfaces
• Can be used as part of warm-up, rehab, or training

Combine with ground poles and dynamic stabilisation exercises for even greater neuromuscular engagement.

09/03/2026

Something to get the maths brains firing, as well as inspire our healthy eating and exercise regimes 😬

🐴Did You Know?!

⚖️ Riders and all of their tack combined should weight no more than 20% of the horse's total body weight!

Staying within this guideline helps reduce strain on the horse's back, joints, and soft tissues, supporting long-term soundness and comfort.

Factors like fitness level, age, conformation, and workload can also play a role in how much weight your horse can comfortably carry.

❤️While the 20% rule is a helpful guideline, it's important to consider these additional factors to best support overall equine well-being.

To learn more about how riders impact horse comfort, check out the following links:
US: https://madbarn.com/how-riders-impact-horses/
CA: https://madbarn.ca/how-riders-impact-horses/