Bit & Bridle

Equine Vertebral Subluxation

Other Names

  • Vertebral subluxation
  • Vertebral misalignment
  • Spinal subluxation
  • Equine vertebral column dysfunction

What is Equine Vertebral Subluxation?

Equine vertebral subluxation is a condition in which one or more vertebrae in the spine are partially displaced or misaligned, disrupting the normal mechanics of the vertebral column. Unlike a full dislocation, a subluxation involves only partial loss of articular contact between adjacent vertebral surfaces. The result is altered movement, nerve irritation, and localised musculoskeletal dysfunction that can affect performance, gait, and the horse’s overall comfort.

The condition can occur anywhere along the cervical (neck), thoracic, lumbar, or sacral regions of the spine, though the cervical and thoracolumbar junction are among the most commonly affected areas. Vertebral subluxation is recognised in equine chiropractic and veterinary sports medicine as a genuine source of back and neck pain, and it is increasingly assessed as part of poor performance investigations in sport horses.

Causes

Vertebral subluxation in horses can arise from a range of mechanical, traumatic, and chronic postural factors:

  • Trauma: Falls, slipping, rearing over backwards, or collisions are common acute causes. Even repetitive minor concussive forces from work on hard surfaces can accumulate over time.
  • Overwork and muscle fatigue: Exhausted postural muscles lose their ability to stabilise the spine, increasing the risk of subtle joint displacement.
  • Poor saddle fit: A poorly fitted saddle creates uneven pressure along the back, altering muscle activation patterns and placing asymmetric load on the vertebral joints.
  • Conformational abnormalities: Horses with long backs, weak hindquarters, or significant conformational faults may be predisposed to spinal stress.
  • Rider imbalance: An asymmetric or stiff rider can induce compensatory spinal patterns in the horse over time.
  • Underlying spinal pathology: Conditions such as osteoarthritis of the facet joints, kissing spines, or spondylosis can all contribute to the development of subluxation.

Symptoms and Signs

The clinical picture varies depending on which spinal region is affected and the severity of the misalignment. Horse owners should watch for:

  • Stiffness or resistance to lateral flexion of the neck or back
  • A shortened stride, particularly behind, or a reluctance to engage the hindquarters
  • Asymmetrical muscle development along the topline
  • Sensitivity or flinching when the back or neck is palpated
  • Resistance to saddling or girthing, pinning ears, or biting when tacked up
  • A general deterioration in performance — loss of impulsion, difficulty with collection, or reluctance to work in a consistent outline
  • Head tilting or persistent one-sidedness
  • In severe cervical cases, neurological signs such as incoordination or stumbling

Diagnosis

Diagnosis begins with a thorough clinical examination by a veterinary surgeon or an equine veterinary chiropractor working under veterinary referral. Key components include:

  • Palpation: Manual assessment of each vertebral segment for heat, swelling, muscle spasm, restricted motion, or pain response
  • Motion assessment: Observation of the horse in-hand and under saddle to identify gait abnormalities and regions of restricted spinal movement
  • Radiography: X-rays of the neck or back can identify structural changes such as arthritis, spondylosis, or kissing spines, though subluxation itself may not always be visible radiographically
  • Scintigraphy (bone scan): Useful for identifying areas of increased bone metabolic activity associated with spinal stress
  • Ultrasound: Can assess soft tissue structures including ligaments and muscle around the vertebral column
  • Nerve blocks: Selective regional anaesthesia may help localise the source of pain

It is important to rule out other causes of back pain such as kissing spines, sacroiliac disease, or hindlimb lameness before concluding that subluxation is the primary issue.

Treatment

Treatment is tailored to the severity, location, and any underlying pathology. Options include:

  • Equine chiropractic adjustment: Performed by a qualified veterinary chiropractor, this involves precisely applied manual forces to specific vertebral segments to restore normal joint motion. In the UK, this must be carried out by or under the supervision of a veterinary surgeon.
  • Physiotherapy and rehabilitation: Targeted exercises to strengthen the core and epaxial muscles reduce the likelihood of recurrence. Carrot stretches, Pessoa training, and pole work are commonly incorporated.
  • Corticosteroid injections: Where facet joint inflammation is identified, local corticosteroid injection under ultrasound guidance can reduce pain and facilitate rehabilitation.
  • Acupuncture: Some horses respond well to acupuncture as an adjunct to musculoskeletal treatment.
  • Rest and modified work: Acute cases may require a period of box rest or light walking before progressive rehabilitation begins.
  • Saddle and tack assessment: Any contributing equipment issues must be addressed — saddle fit should be reassessed by a qualified saddle fitter.

Prevention

While not all cases are preventable, the following measures significantly reduce risk:

  • Regular saddle fit checks — at least once or twice a year, and whenever the horse’s topline changes
  • Progressive training programmes that build core and hindquarter strength before demanding collection work
  • Good footing — avoid working consistently on hard or uneven ground
  • Balanced riding and regular rider position assessments
  • Routine veterinary and physiotherapy check-ups for sport horses in intensive work

Prognosis

For horses with functional subluxation and no underlying structural pathology, the prognosis is generally good with appropriate treatment and management changes. Many horses return to full work after a course of chiropractic and physiotherapy. Where underlying conditions such as kissing spines or facet joint arthritis are present, prognosis depends on the severity of those findings, but most horses can still be maintained in comfortable work with ongoing management.

When to Call the Vet

Contact your veterinary surgeon if your horse shows any of the following:

  • Sudden onset of back or neck pain following a fall or trauma
  • Progressive deterioration in performance that has not responded to saddle changes or rest
  • Any neurological signs — stumbling, weakness behind, or incoordination
  • Persistent one-sidedness, resistance to flexion, or unwillingness to work in both directions

Frequently Asked Questions

Can horses recover fully from vertebral subluxation?

Many horses make a full recovery, especially when the subluxation is identified early and there is no significant underlying structural disease. A tailored rehabilitation programme combining chiropractic care, physiotherapy, and modified exercise is typically the most effective approach.

Is equine chiropractic treatment effective for spinal subluxation?

Evidence from clinical practice and a growing body of research supports chiropractic manipulation as a useful tool for improving spinal mobility and reducing pain in horses with vertebral dysfunction. It is best used alongside a comprehensive rehabilitation plan rather than as a standalone treatment. See BEVA guidance on complementary therapies for context.

How do I know if my horse has back pain from subluxation or another cause?

Back pain has many potential causes in horses, including navicular disease, sacroiliac joint dysfunction, muscle strain, and hindlimb lameness referred to the back. A thorough veterinary investigation is necessary to distinguish between them before committing to a treatment plan.

Does saddle fit really affect the horse’s spine?

Yes, significantly. A poorly fitted saddle can create focal pressure points that cause muscle atrophy, pain, and altered movement patterns. Over time, this places uneven mechanical stress on the vertebral joints. Regular saddle fit assessments are one of the most cost-effective preventive measures available to horse owners.