Horse Back Pain: Causes, Signs, and What You Can Do About It

A horse that pins its ears during saddling. A gelding that dips sharply when you mount. A mare that's become mysteriously resistant to collection. A show horse whose flying changes have gone from clean to ugly overnight. Nine times out of ten, the first thing people investigate is the legs. But the problem might be six inches higher. Back pain in horses is staggeringly common, chronically underdiagnosed, and responsible for more behavioral and performance issues than most riders want to admit.

Thoracolumbar Anatomy: What We're Working With

The equine back is an engineering marvel that we routinely ask to do something it wasn't originally designed for: carry a rider. Understanding the basic anatomy helps explain why things go wrong.

The thoracolumbar spine consists of 18 thoracic vertebrae (each paired with a rib) and 6 lumbar vertebrae, creating the bridge between the forehand and hindquarters. Each vertebra has a body (ventral), a vertebral arch protecting the spinal cord, and a dorsal spinous process, the bony projections you can feel when you run your hand along the horse's topline.

These spinous processes are tallest at the withers (T3-T5, reaching up to 30 cm in some horses) and decrease in height as they move caudally through the thoracic and lumbar regions. The spaces between adjacent spinous processes matter enormously, as we'll see when we discuss kissing spines.

Layered over this bony framework is an intricate system of muscles and ligaments. The longissimus dorsi is the largest and most important, running the length of the back on either side of the spine. The multifidus muscles, a series of small, deep muscles connecting adjacent vertebrae, provide segmental stability. The supraspinous ligament runs along the tips of the spinous processes, and the nuchal ligament continues forward to support the head and neck.

The thoracolumbar fascia, a tough connective tissue sheet, wraps around and between muscle layers, transmitting forces between the hindquarters and forehand. When this system works well, the horse moves with fluid, elastic power. When something hurts, the whole chain breaks down.

Common Causes of Equine Back Pain

Saddle Fit

Poorly fitting saddles cause more back pain than any single pathological condition. A saddle that bridges (contacts at front and back but not in the middle), pinches the withers, sits crooked, or concentrates pressure on small areas creates chronic focal pain that produces muscle spasm, atrophy, and eventually structural damage. White hairs in the saddle area, dry spots in an otherwise sweaty saddle pad, and asymmetric muscle development are all red flags. Getting a proper saddle fit evaluation should be step one in any back pain investigation.

Rider Imbalance

Nobody wants to hear this one, but riders are frequently part of the problem. A rider who sits crooked, collapses one hip, grips with the knees, or bounces at the sitting trot creates asymmetric and repetitive forces that the horse's back must absorb. Studies have shown that rider weight relative to horse size matters too. A horse carrying an appropriately balanced rider at 15% of its body weight handles the load differently than one carrying 25% from an unbalanced rider.

Kissing Spines (Overriding Dorsal Spinous Processes)

When adjacent spinous processes lose the normal space between them and begin touching or overlapping, the periosteum (bone covering) becomes inflamed where they contact, producing significant pain. The most commonly affected area is T13-T18, directly under the saddle. Kissing spines are diagnosed radiographically and range from mild narrowing to complete overlap with bony remodeling. Some horses with dramatic radiographic changes show minimal clinical signs, while others with modest changes are in obvious pain. The correlation between X-ray severity and clinical significance is frustratingly inconsistent.

Sacroiliac Dysfunction

The sacroiliac joint connects the spine to the pelvis and transmits propulsive forces from the hindquarters into forward movement. Sacroiliac pain is common in performance horses, particularly dressage horses, jumpers, and barrel racers. It's also notoriously difficult to diagnose because the joint is buried deep beneath the gluteal muscles and cannot be directly palpated or easily imaged. Asymmetric tuber sacrale height ("hunter's bump"), reluctance to engage behind, and difficulty with lateral work are suggestive but not diagnostic.

Primary Muscle Strain

The longissimus dorsi and multifidus muscles can be strained by sudden exertion, a bad step, a fall, or chronic overwork without adequate conditioning. Muscle injuries often resolve with rest and appropriate therapy but can become chronic if the horse continues working through pain, developing compensatory movement patterns that stress other structures.

Other Causes

Vertebral fractures (particularly in young horses during breaking), discospondylitis (vertebral infection), osteoarthritis of the articular process joints, and referred pain from hindlimb lameness or ulcers can all manifest as apparent back pain. A thorough workup considers the whole horse, not just the back in isolation.

Behavioral Signs: What Your Horse Is Trying to Tell You

Horses with back pain rarely limp in the traditional sense. Instead, they communicate through behavior changes and subtle performance deficits that are easy to misinterpret as attitude problems.

• Girthiness: Ears pinned, turning to bite, or flinching when the girth is tightened
• Resistance to saddling: Moving away, dropping the back, or tensing when the saddle is placed
• Bucking or kicking out: Especially during transitions, canter departures, or when asked to engage the hindquarters
• Reluctance to go forward: A horse that feels "stuck" or requires excessive leg
• Difficulty with lateral work: Stiffness through the body, resistance to bending
• Loss of impulsion: Shorter stride behind, dragging toes, reluctance to track up
• Changes in jumping form: Hanging legs, rushing fences, refusing
• Head tossing or high head carriage: Attempting to avoid rounding the back
• Difficulty standing for the farrier: Especially picking up hind feet, which requires shifting weight onto the back
• Changes in posture: Roached (arched) back, tucked pelvis, standing camped out behind

The challenge is that every one of these signs can have other explanations. Ulcers cause girthiness. Hock pain causes resistance to collection. Training gaps cause bucking. Context matters, and a single sign in isolation isn't diagnostic. But a pattern of multiple behavioral changes, especially if they developed gradually in a horse that previously performed well, warrants a back evaluation.

Palpation Assessment: Hands-On Evaluation

A skilled veterinarian or therapist can learn a tremendous amount through systematic palpation of the equine back. The assessment typically follows a standard protocol:

Standing behind the horse (carefully), evaluate symmetry of the gluteal and epaxial muscles. Note any visible atrophy, asymmetry, or swelling. Then, using firm but graduated pressure along the longissimus dorsi from withers to croup, assess for pain responses: flinching, dipping the back, muscle fasciculation, swishing the tail, attempting to kick, or turning to bite.

Apply ventral pressure along the spinous processes to look for segmental pain. Perform dynamic tests: running a blunt object (pen cap, hoof pick handle) along the paravertebral muscles to assess reflexive lateral flexion (should produce a smooth, symmetric curve). Apply downward pressure on the croup to evaluate lumbosacral flexion. Lift the tail to assess resistance.

Palpation is subjective, operator-dependent, and influenced by the horse's temperament. Some horses are stoic and won't react until pain is severe. Others are hypersensitive and flinch at everything. Experience and systematic approach make the difference between useful information and noise.

Diagnostic Tools: Seeing What Hands Can't Feel

Radiography: Standard X-rays of the thoracolumbar spine show bony changes: kissing spines, articular process joint arthritis, vertebral fractures, and remodeling. Portable digital X-ray units have made field radiography practical. Limitations include the inability to image soft tissues and the inconsistent correlation between radiographic changes and clinical significance.

Ultrasound: Excellent for evaluating the supraspinous ligament, multifidus muscles, and articular process joints. Ultrasound can detect ligament tears, muscle atrophy, joint effusion, and even some spinous process pathology. It's readily available, relatively inexpensive, and can be performed in the field.

Nuclear Scintigraphy (Bone Scan): Radioactive technetium is injected intravenously and concentrates in areas of active bone turnover. A gamma camera then maps where the "hot spots" are. Scintigraphy is highly sensitive for detecting active bony pathology (kissing spines, stress fractures, sacroiliac inflammation) but requires referral to a hospital with nuclear medicine capability. It shows where bone is remodeling but doesn't tell you the specific diagnosis.

Thermography: Infrared cameras detect surface temperature variations that reflect underlying inflammation or altered blood flow. Increased heat over a specific vertebral segment or muscle group can guide further investigation. Thermography is non-invasive and painless, making it a useful screening tool, though it lacks specificity.

MRI: The gold standard for soft tissue imaging, but practical limitations (cost, availability, requirement for general anesthesia to image the back) restrict its use to referral hospitals and selected cases.

Treatment Options

Chiropractic (Veterinary Spinal Manipulation Therapy): Certified veterinary chiropractors use controlled manual thrusts to restore mobility to restricted vertebral segments. When performed by trained professionals, chiropractic adjustments can provide rapid improvement in horses with biomechanical restrictions and secondary muscle spasm. Avoid unlicensed practitioners. A bad adjustment on a horse with an underlying fracture or severe kissing spines can cause serious harm.

Massage and Myofascial Release: Targeted soft tissue work addresses muscle tension, trigger points, and fascial restrictions. Particularly useful for primary muscle pain and as a complement to other treatments. Many horses show visible relaxation and improved range of motion after skilled bodywork.

Extracorporeal Shockwave Therapy (ESWT): Focused acoustic waves are delivered to specific areas of the back, stimulating healing, reducing pain, and promoting bone remodeling. Shockwave has shown promising results for kissing spines and ligament injuries. Typically administered in 3 sessions, 2-3 weeks apart. Note that shockwave has analgesic effects lasting 2-3 days, so FEI regulations prohibit its use within 5 days of competition.

Mesotherapy: Multiple small intradermal injections of anti-inflammatory agents (often a combination of methylprednisolone, saline, and local anesthetic) along the paravertebral muscles. The technique targets cutaneous nerve endings and can interrupt chronic pain cycles. Effects are often dramatic and rapid, though some horses require repeated treatments.

Corticosteroid Injection: Ultrasound-guided injection of corticosteroids into specific sites (interspinous spaces for kissing spines, articular process joints) provides targeted anti-inflammatory effects. This is a common approach for kissing spines that haven't responded to conservative management.

Surgery: For severe kissing spines unresponsive to conservative treatment, interspinous ligament desmotomy (cutting the ligament between affected spinous processes) or subtotal ostectomy (removing portions of the impinging spinous processes) can provide long-term relief. Success rates in appropriately selected cases exceed 70%.

Rehabilitation Exercises

Treatment without rehabilitation is like fixing a roof leak but never cleaning up the water damage. The muscles that support and mobilize the spine need targeted reconditioning.

Baited stretches (carrot stretches): Using a treat, guide the horse's nose toward its chest, each flank, between the front legs, and toward each hind fetlock. These stretches recruit and strengthen the multifidus and core stabilizing muscles. Perform 3-5 repetitions of each position, holding for 5 seconds, 3-5 times per week.

Ground poles and cavaletti: Walking and trotting over regularly spaced poles encourages the horse to lift its back, flex its joints, and engage core muscles. Start with poles on the ground and progress to raised cavaletti as strength improves.

Hill work: Walking up and down gentle inclines strengthens the hindquarters, core, and postural muscles. Hill work is one of the most effective and accessible rehabilitation tools available.

Belly lifts: Apply light pressure with fingertips to the ventral midline (or use a blunt object) to stimulate reflexive contraction of the abdominal muscles and elevation of the back. Hold for 5 seconds, repeat 5 times. This is the equine equivalent of a plank exercise.

Long and low work: Encouraging the horse to stretch forward and down through the neck in walk and trot opens the spaces between dorsal spinous processes and engages the core stabilizers. Lunging in a correctly fitted chambon or elastic training aid can facilitate this posture.

Addressing Root Causes

None of the treatments above will produce lasting results if the underlying cause persists. A horse treated for back pain and returned to work in a poorly fitting saddle with an unbalanced rider will be back pain within weeks. Address the cause alongside the symptom.

Get the saddle checked by a qualified fitter. Take an honest look at your own riding. Consider lessons focused on your biomechanics, not just the horse's training. Review the workload: is the horse being asked to do more than its current fitness level supports? Treat any concurrent issues, because hindlimb lameness, dental problems, and gastric ulcers can all drive compensatory back pain.

Frequently Asked Questions

Explore More

Understanding how the spine, muscles, and ligaments work together is essential for recognizing and preventing back problems. Explore the full equine musculoskeletal system in our interactive 3D anatomy models.

Sources

• Haussler, K.K. "Back Problems: Diagnosis and Management." Equine Sports Medicine and Surgery, 2nd ed., Saunders, 2014.
• Jeffcott, L.B. "Disorders of the Thoracolumbar Spine of the Horse: A Survey of 443 Cases." Equine Veterinary Journal, 1980.
• Turner, T.A. "Diagnostic Thermography." Veterinary Clinics of North America: Equine Practice, 2001.
• Stubbs, N.C., et al. "Dynamic Mobilisation Exercises Increase Cross-Sectional Area of Musculus Multifidus." Equine Veterinary Journal, 2011.
• AAEP. "Back Pain in the Horse." American Association of Equine Practitioners Proceedings.