Understanding Kissing Spine in Horses: Diagnosis, Treatment, and Management

What is Kissing Spine?

Kissing spine, medically termed overriding dorsal spinous processes (ORDSP) or impinging spinous processes, is a painful condition affecting the vertebrae in a horse’s back. This disorder occurs when the bony projections extending upward from the vertebrae—called the dorsal spinous processes—become abnormally close together or actually make contact with one another, causing pain, inflammation, and potentially bone remodeling.

The vertebral column (spine) consists of individual bones called vertebrae stacked from the base of the skull to the tail. Each vertebra has a main body (centrum) plus several bony projections: the dorsal spinous process extending upward, transverse processes extending laterally, and articular processes that form joints between adjacent vertebrae. In the thoracic and lumbar regions (the back and loin areas where saddles sit), the dorsal spinous processes are particularly prominent, extending several inches above the vertebral body.

In healthy horses, these dorsal spinous processes are separated by spaces containing interspinous ligaments—tough, fibrous connective tissues that connect adjacent processes and help stabilize the spine while allowing normal flexibility. Each process is also covered by periosteum (a specialized tissue layer covering bone) and surrounded by muscles, fascia, and other soft tissues.

Kissing spine develops when the normal spacing between dorsal spinous processes is reduced or eliminated. The processes may simply be positioned very close together (impingement), or they may actually touch and rub against each other during spinal movement (true “kissing”). This abnormal contact or near-contact causes several problems:

Mechanical pain from bone-on-bone contact or pressure on compressed soft tissues
Inflammation of the periosteum, interspinous ligaments, and surrounding tissues
Bone remodeling including sclerosis (increased bone density), lysis (bone breakdown), and formation of new bone at contact points
Muscle spasm and dysfunction in surrounding back muscles responding to pain and altered biomechanics
Reduced spinal flexibility limiting the horse’s ability to move comfortably

Kissing spine represents a common cause of back pain in horses, particularly in athletic horses performing collected work, jumping, or other activities that stress the back. The condition affects horses across all breeds and disciplines, though certain factors increase susceptibility. While kissing spine can be a career-limiting or career-ending problem, many horses respond well to appropriate treatment, particularly when the condition is identified early and managed comprehensively.

Anatomy of the Equine Spine

Understanding the normal anatomy of the horse’s back provides essential context for comprehending how kissing spine develops and why it causes problems.

The equine vertebral column consists of approximately 54 vertebrae divided into regions:

Cervical vertebrae (neck): 7 bones with relatively short dorsal spinous processes
Thoracic vertebrae (back/ribcage): 18 bones with tall dorsal spinous processes, particularly prominent at T13-T17
Lumbar vertebrae (loin): 6 bones with shorter, wider dorsal spinous processes oriented more horizontally
Sacral vertebrae (croup): 5 fused bones forming the sacrum
Coccygeal vertebrae (tail): 15-21 bones

Kissing spine most commonly affects the thoracic vertebrae, particularly the caudal (rear) thoracic region from approximately T13 through T18, and sometimes the cranial (front) lumbar vertebrae. This region experiences the greatest forces from saddle placement, rider weight, and the biomechanics of athletic movement.

The dorsal spinous processes vary considerably in height, shape, and orientation along the spine. The thoracic processes are tallest in the mid to caudal thoracic region, reaching heights of 6-10 inches or more above the vertebral body. These tall processes create the characteristic “withers” (the highest point of the back at the base of the neck) and continue along the back under the saddle area.

The anticlinal vertebra (typically T16 or T17) represents a transitional point where the dorsal spinous processes change from angling backward to angling forward. This vertebra has an upright spinous process, and it represents a biomechanically important point in the spine’s structure. The region around the anticlinal vertebra frequently experiences kissing spine problems.

Normal spacing between adjacent dorsal spinous processes varies among individuals and along different portions of the spine, but healthy horses maintain gaps of several millimeters to over a centimeter between processes. This spacing allows for the interspinous ligaments and provides clearance for normal spinal flexion, extension, and lateral bending movements.

The thoracolumbar fascia and multiple muscle layers surround the vertebrae, including the longissimus dorsi (the primary back muscle extending along either side of the spine), multifidus, and other deep spinal stabilizers. These muscles work together to support the spine, transmit forces between front and hindquarters, and enable the controlled spinal movements essential for athletic performance.

Causes and Risk Factors

The development of kissing spine involves multiple contributing factors, often working in combination. While the exact cause in individual horses may be difficult to pinpoint, several recognized risk factors and mechanisms have been identified.

Conformational Factors

Natural anatomical variation means some horses are born with dorsal spinous processes positioned closer together than others. Horses with:

Naturally narrow interspinous spaces: Some individuals have genetically determined process positioning that leaves minimal clearance
Long, prominent dorsal spinous processes: Taller processes increase the likelihood of impingement
Long backs: Horses with long back conformation may experience greater forces and movement in the thoracolumbar region
Weak toplines: Poor muscular development over the back provides less support and shock absorption

These conformational characteristics don’t necessarily cause kissing spine independently but increase susceptibility when combined with other factors.

Biomechanical and Training Factors

Poor posture and movement patterns significantly contribute to kissing spine development:

Hollow back posture: Horses working in extended, hollow-backed positions (with head elevated and back dropped) bring the dorsal spinous processes closer together dorsally (at the top). This “hyperextension” of the spine reduces interspinous spacing and increases impingement risk. Unfortunately, young or poorly trained horses, horses with weak back muscles, or those ridden by unbalanced riders often travel in this detrimental posture.

Lack of proper engagement: Horses working without engaging their hindquarters and lifting their backs fail to develop the muscular support necessary for spinal health. Proper engagement involves the horse “rounding” its back by activating core and back muscles, which slightly flexes the spine and increases interspinous spacing.

Inappropriate training progression: Starting intensive work too young, before the spine and supporting structures have fully matured and strengthened, may contribute to problems. Horses’ vertebrae continue developing into their late teens, and excessive stress during growth periods can potentially affect development.

Repetitive stress: Certain disciplines involve repetitive movements that stress the thoracolumbar spine, particularly:

Jumping (landing impacts and spinal compression)
Dressage (collected movements requiring significant engagement and back lifting)
Racing (galloping places substantial forces through the spine)
Reining and other Western performance sports (sliding stops, spins)

Saddle Fit and Rider Factors

Poorly fitted saddles create focal pressure points that can contribute to back pain and potentially influence kissing spine:

Saddles positioned too far forward or backward
Saddles with trees too narrow, too wide, or incorrectly shaped
Saddles with inadequate panel flocking creating pressure points
Saddles positioned directly over affected vertebrae

Unbalanced or heavy riders place asymmetric or excessive loads on the horse’s back, potentially contributing to poor posture and biomechanical stress.

Injury and Trauma

Direct trauma to the back from falls, kicks, rearing over backward, or other accidents can potentially damage spinal structures and contribute to kissing spine development.

Compensatory mechanisms: Horses with lameness or pain in the limbs may alter their movement patterns to compensate, changing how forces transmit through the spine and potentially contributing to back problems.

Age and Degenerative Changes

While kissing spine can affect horses of any age, middle-aged to older horses more commonly show radiographic signs, suggesting that degenerative processes and accumulated stress over years of work contribute to development. The condition may begin subtly and progress gradually, with clinical signs becoming apparent only after considerable change has occurred.

Genetic Predisposition

Some evidence suggests hereditary factors may influence individual susceptibility, though specific genetic mechanisms remain incompletely understood. Certain bloodlines or breeds may show higher incidence, suggesting genetic influences on vertebral conformation or other relevant factors.

Clinical Signs and Symptoms

Horses with kissing spine demonstrate variable clinical presentations ranging from subtle performance issues to obvious pain and behavioral problems. Importantly, not all horses with radiographic evidence of kissing spine show clinical signs—some horses with close or touching processes remain asympressively sound, while others with seemingly minor radiographic findings experience significant pain.

Performance-Related Signs

Reduced performance often represents the primary complaint:

Difficulty with collected work: Horses may resist or struggle with movements requiring back engagement and lifting
Reluctance to jump or jump poorly: Affected horses may refuse jumps, knock rails, or jump hollow-backed rather than with proper bascule (rounding)
Stiffness or resistance to lateral work: Difficulty bending, two-tracking, or performing lateral movements
Inability to maintain gaits: Breaking from canter to trot, irregular rhythm, or difficulty with transitions
Loss of forward impulsion: Reluctance to move energetically forward
Deteriorating movement quality: Loss of suspension, shortened stride, or irregular movement patterns

Behavioral Signs

Behavioral changes reflecting discomfort may include:

Resistance when saddled or mounted: Pinning ears, moving away, cow-kicking, biting, or other expressions of anticipatory pain
Bucking, rearing, or bolting: Pain-related evasions during work
Cold-backed behavior: Humping the back or moving stiffly when first mounted, gradually improving with movement as muscles warm up
Difficulty standing for grooming: Particularly when brushing over the back
Aggressive responses to back palpation or pressure
Changes in temperament: Previously willing horses becoming sour, resistant, or dangerous

Physical Examination Findings

Back palpation during clinical examination often reveals:

Pain response when firm pressure is applied along the dorsal spinous processes, particularly in affected regions
Muscle tension or spasm in back muscles, often asymmetric
Muscle atrophy along the topline, particularly the longissimus dorsi muscles, indicating chronic disuse or pain
Reduced spinal flexibility: Limited range of motion during flexion, extension, or lateral bending tests
Negative response to back stretching exercises: Pain or resistance when asked to round the back or reach down and forward

Dynamic evaluation:

Gait abnormalities: Stiffness, shortened stride, irregular rhythm, or reluctance to engage hindquarters
Pain during specific movements: Particularly during transitions, lateral work, or when asked to collect
Hindlimb lameness: Sometimes concurrent or compensatory lameness develops

Important Considerations

Non-specific signs: Many kissing spine symptoms overlap with numerous other conditions (muscle soreness, saddle fit issues, other back pathology, hindlimb lameness, rider problems), making diagnosis based solely on clinical signs unreliable.

Variable presentation: Some horses with severe radiographic changes show minimal clinical signs, while others with modest changes experience significant pain—the correlation between radiographic appearance and clinical severity is imperfect.

Concurrent conditions: Kissing spine often coexists with other problems including sacroiliac disease, hindlimb lameness, muscle pathology, or saddle fit issues. Comprehensive evaluation is essential.

Diagnosis

Diagnosing kissing spine requires combining clinical findings with diagnostic imaging, as neither alone provides definitive diagnosis.

Clinical Examination

A thorough physical and lameness examination includes:

Complete history including performance changes, behavioral issues, and timeline of problem development
Static examination of conformation and muscle development
Palpation of the entire back, assessing pain response and muscle condition
Range of motion testing of the spine
Observation of the horse under saddle when possible
Comprehensive lameness evaluation to identify concurrent limb problems

Radiography (X-rays)

Radiographs remain the primary diagnostic imaging modality for kissing spine:

Technique: High-quality lateral radiographs of the thoracolumbar spine require:

Powerful x-ray equipment capable of penetrating the thick tissues over the spine
Proper positioning with the horse standing squarely
Multiple overlapping images to cover the entire thoracic and lumbar regions
Sometimes oblique or dorsoventral views for additional information

Radiographic findings associated with kissing spine include:

Reduced interspinous space: The hallmark finding is narrowed or absent space between adjacent dorsal spinous processes. Measurement of these spaces and comparison to normal reference values helps quantify severity.

Bone remodeling: Changes at the affected sites may include:

Sclerosis (increased bone density appearing as whiter, more opaque bone at contact points)
Bone lysis (areas of bone breakdown appearing as darker, radiolucent zones)
New bone formation at contact sites creating irregular contours or bony bridges
Periosteal reaction (new bone formation on the surface of processes)

Shape changes: Chronic cases may show remodeling producing abnormal process shapes, including flattening, beveling, or cupping at contact points.

Radiolucent lines: Fine dark lines within bone may indicate areas of active bone remodeling or microfractures.

Radiographic interpretation challenges:

Normal variation: Some narrowing of interspinous spaces is normal in certain locations, particularly around the anticlinal vertebra. Determining what constitutes “abnormal” requires experience and consideration of the full clinical picture.

Incidental findings: Radiographic changes may be present in horses without clinical signs, meaning radiographic abnormalities alone don’t confirm clinically significant kissing spine.

False negatives: Early kissing spine may not yet show obvious radiographic changes, particularly bone remodeling.

Nuclear Scintigraphy (Bone Scan)

Bone scintigraphy involves injecting radioactive tracer that accumulates in areas of active bone remodeling, then using special cameras to image the tracer distribution:

Advantages:

Detects areas of active inflammation and bone remodeling before obvious radiographic changes develop
Images the entire spine simultaneously, identifying all affected sites
Helps differentiate clinically significant lesions (showing increased tracer uptake) from incidental radiographic findings (without increased uptake)
Can identify concurrent problems in other areas (sacroiliac region, hindlimbs)

Limitations:

Expensive and available only at referral centers
Involves radioactive materials requiring special handling and facilities
Provides less anatomic detail than other imaging modalities
False positives can occur with other causes of inflammation

Interpretation: Increased radiopharmaceutical uptake in the dorsal spinous processes, particularly when corresponding to radiographic abnormalities and clinical signs, strongly supports clinically significant kissing spine diagnosis.

Advanced Imaging

Ultrasound examination of the back can assess:

Soft tissue structures including muscles, ligaments, and fascia
In some cases, the superficial aspects of dorsal spinous processes
However, ultrasound cannot penetrate deeply enough to fully evaluate interspinous spaces

Thermography (infrared imaging) may identify areas of increased heat associated with inflammation but is non-specific and cannot definitively diagnose kissing spine.

CT or MRI scanning provides superior detail but is generally impractical for imaging the equine thoracolumbar spine due to equipment size limitations, expense, and the need for general anesthesia.

Diagnostic Local Anesthesia

Injection of local anesthetic into affected interspinous spaces (interspinous injection blocks) can help confirm that pain originates from specific locations:

Temporary improvement in clinical signs following injection supports that the blocked area is a pain source
This technique helps differentiate kissing spine from other back pain causes
Multiple sites may need blocking if several areas are affected
Response must be evaluated carefully as some placebo effect may occur

Integrating Diagnostic Findings

Definitive diagnosis of clinically significant kissing spine requires:

Compatible clinical signs and examination findings
Radiographic evidence of reduced interspinous spacing with or without bone remodeling
Ideally, scintigraphic evidence of active inflammation at affected sites
Exclusion or identification of concurrent conditions
Response to diagnostic anesthesia when performed

Treatment Options

Managing kissing spine involves multiple treatment modalities often used in combination. Treatment selection depends on severity, the horse’s intended use, owner resources, and response to conservative approaches.

Conservative (Non-Surgical) Management

Many horses with kissing spine respond favorably to conservative treatment, particularly when the condition is identified early and addressed comprehensively.

Rest and Rehabilitation

Initial rest period: Horses with acute pain typically benefit from rest ranging from several weeks to several months, allowing inflammation to subside. However, complete stall rest is generally avoided—controlled exercise with gradual progression proves more beneficial than prolonged inactivity.

Structured rehabilitation program:

Phase 1 (Weeks 1-4): Hand walking and/or controlled turnout in small paddocks. Focus on maintaining general fitness without stressing the back.

Phase 2 (Weeks 4-12): Gradual introduction of ridden work emphasizing:

Core strengthening exercises: Ground poles, hill work, transitions
Long and low work: Encouraging horses to stretch forward and down, engaging back muscles and opening interspinous spaces
Lateral work: Gentle leg yields, turns on the forehand/haunches promoting suppleness
Building topline strength: Progressive exercises developing muscles that support the spine

Phase 3 (Months 3-6+): Gradual return to discipline-specific work while maintaining emphasis on correct posture and engagement. Permanent incorporation of back-strengthening exercises into regular training.

Medication and Pain Management

Non-steroidal anti-inflammatory drugs (NSAIDs):

Phenylbutazone (bute), flunixin meglumine (Banamine), or firocoxib (Equioxx) reduce pain and inflammation
Used during acute painful episodes or short-term during rehabilitation
Long-term daily NSAID use is generally avoided due to side effect risks (gastric ulcers, kidney damage, colitis)

Muscle relaxants:

Methocarbamol or robaxin help reduce muscle spasm
Used short-term during acute episodes

Corticosteroid injections:

Interspinous injections of corticosteroids (typically triamcinolone or methylprednisolone) directly into affected interspinous spaces
Provides localized anti-inflammatory effect
May offer weeks to months of pain relief
Can be repeated periodically but not indefinitely
Risks include infection, tissue weakening with repeated injections

Alternative pain management:

Gabapentin for neuropathic pain components
Adequan or Legend (polysulfated glycosaminoglycans or hyaluronic acid) for potential anti-inflammatory effects
Various supplements marketed for joint and back health (efficacy variable and often unproven)

Physical Therapy and Bodywork

Chiropractic care: Veterinary chiropractors or certified animal chiropractors perform spinal adjustments that may provide temporary relief and improve movement patterns. Regular maintenance adjustments may help some horses.

Massage therapy: Therapeutic massage addresses muscle tension, spasm, and compensatory muscle patterns. Regular massage can support rehabilitation efforts.

Acupuncture: Traditional needle acupuncture or electroacupuncture may provide pain relief and reduce inflammation in some horses. Multiple sessions are typically required.

Therapeutic exercise programs: Working with equine physical therapists or rehabilitation specialists to develop customized exercise protocols optimizes recovery.

Hydrotherapy: Swimming or water treadmill exercise provides low-impact cardiovascular conditioning and muscle strengthening without stressing the back.

Electromagnetic therapies: Pulsed electromagnetic field (PEMF) therapy, therapeutic ultrasound, or laser therapy may reduce inflammation and promote healing, though evidence for efficacy is limited.

Management Modifications

Saddle fit evaluation and correction: Professional saddle fitting ensuring the saddle:

Distributes weight appropriately without creating pressure points
Clears the spine adequately
Positions correctly relative to the horse’s conformation
May require custom or specialized saddles for horses with significant back pathology

Rider evaluation and training: Working with qualified instructors to ensure:

Balanced, effective riding that doesn’t contribute to poor posture
Appropriate training methods that encourage back engagement
Realistic expectations and suitable work intensity

Equipment modifications:

Back support pads or specialized saddle pads
Modified tack that reduces pressure on sensitive areas

Lifestyle adjustments:

Adequate turnout promoting natural movement and muscle maintenance
Appropriate footing in work areas reducing jarring impacts
Discipline modifications (changing from jumping to dressage, reducing intensity, etc.)

Extracorporeal Shockwave Therapy (ESWT)

Shockwave therapy delivers focused acoustic energy pulses to affected tissues:

May stimulate healing, reduce pain, and promote bone remodeling
Typically administered in multiple sessions (3-6 treatments) spaced 1-3 weeks apart
Many horses show improvement though results vary
Relatively low risk with minimal side effects
Expense and availability may limit use
Competition horses must observe mandatory withdrawal periods (many organizations ban competing for specified periods after ESWT due to potential pain-masking effects)

Surgical Treatment

When conservative management fails to provide adequate relief or for horses with severe disease, surgical interventionmay be considered.

Interspinous Ligament Desmotomy (ISLD)

This minimally invasive procedure involves cutting the interspinous ligaments between affected processes:

Technique:

Performed under standing sedation with local anesthesia
Using a specialized cutting instrument (ligament knife or modified biopsy punch) inserted between processes
The interspinous ligament is severed, reducing compression between processes
Multiple affected spaces can be treated in one procedure
Typically performed under ultrasound or fluoroscopic guidance

Theory: Removing the ligament reduces compressive forces between processes and may allow slightly increased spacing. The procedure also denervates (cuts nerves in) the area, reducing pain sensation.

Success rates: Studies report 60-80% of horses return to work at some level following ISLD, with best results in horses with:

Mild to moderate disease
Clear identification of specific affected sites
Comprehensive post-operative rehabilitation
Appropriate ongoing management

Recovery: Horses typically rest 2-4 weeks post-operatively, then begin gradual rehabilitation over 3-6 months before returning to full work.

Risks and complications:

Infection (relatively low risk)
Hemorrhage (uncommon)
Incomplete ligament transection requiring repeat procedure
No guarantee of success—some horses don’t improve
Long-term stability effects unknown (the ligaments do provide some spinal support)

Partial Ostectomy (Bone Removal)

For severe cases with extensive bone remodeling or cases failing ISLD, partial removal of portions of affected dorsal spinous processes may be performed:

Technique:

Requires general anesthesia
Surgical approach through the back muscles to access affected processes
Removal of bone from the tops or opposing surfaces of impinging processes, creating permanent spacing
More invasive than ISLD with longer recovery

Indications: Severe disease with extensive bone changes, failure of less invasive treatments, or cases where multiple levels are severely affected.

Success rates: Variable, roughly 50-70% return to some level of work, with better results in carefully selected cases.

Recovery: Several months of rehabilitation required, with gradual return to work over 6-9 months or longer.

Risks: All surgical risks including infection, hemorrhage, anesthetic complications, plus specific concerns about destabilizing the spine if too much bone is removed.

Other Surgical Approaches

Various other techniques have been described including:

Different approaches to ligament cutting
Combination procedures
Implant placement to maintain spacing

These are less commonly performed and success rates vary.

Regenerative Medicine

Emerging therapies including platelet-rich plasma (PRP), stem cells, or other biological products injected into affected interspinous spaces show promise in some cases but remain investigational with limited published evidence for efficacy.

Treatment Algorithm

A typical treatment progression might include:

Initial conservative management (3-6 months): Rest, rehabilitation, medication, management modifications
Evaluation of response: If inadequate improvement, proceed to more aggressive options
Interspinous corticosteroid injections or ESWT: If some improvement with conservative care but not sufficient
Surgical intervention (ISLD): If conservative approaches fail but horse is otherwise a good candidate
More aggressive surgery: For severe cases or those failing ISLD
Maintenance management: For horses that improve, ongoing attention to training, saddle fit, and body conditioning

Prognosis and Return to Work

Outcomes vary considerably based on multiple factors:

Favorable prognostic factors:

Mild to moderate disease severity
Early diagnosis and intervention
Well-defined, limited number of affected sites
Young to middle-aged horses
Owners committed to comprehensive rehabilitation and ongoing management
Appropriate modification of work demands
Good response to conservative treatment

Poorer prognosis:

Severe, extensive disease affecting multiple sites
Chronic, long-standing cases with extensive bone remodeling
Concurrent significant pathology (sacroiliac disease, severe hindlimb problems)
Older horses with degenerative changes
Poor response to conservative management
Unrealistic expectations or inappropriate return to demanding work

General outcomes:

With conservative management: 50-70% of horses may return to some level of work, though often with reduced intensity or discipline changes
With ISLD surgery: 60-80% return to work at some level
Complete return to previous high-level performance: Variable, perhaps 30-50% depending on discipline demands
Some horses require permanent work restrictions or retirement

Realistic expectations: Many horses with kissing spine can continue useful careers with appropriate management, though they may need:

Permanent incorporation of back-strengthening exercises
Regular bodywork (chiropractic, massage)
Meticulous saddle fitting
Modified work intensity or discipline changes
Ongoing attention to proper biomechanics and training

Prevention Strategies

While kissing spine cannot always be prevented, several strategies may reduce risk:

Appropriate training methods:

Emphasizing correct engagement and back use from early training
Avoiding prolonged hollow-backed work
Progressive conditioning allowing proper muscular development
Appropriate work intensity for horse’s age and development stage

Regular back strengthening exercises:

Ground pole work
Hill work
Transitions
Long and low stretching
Core strengthening exercises

Proper saddle fit:

Professional saddle fitting
Regular evaluation as horses change shape
Appropriate saddle selection for horse’s conformation

Rider education:

Balanced, effective riding
Understanding of correct biomechanics
Appropriate skill level for horse being ridden

Appropriate horse selection:

Considering conformation for intended discipline
Awareness of breed or bloodline susceptibilities
Pre-purchase examinations including back evaluation

Regular veterinary and bodywork care:

Addressing back discomfort early
Regular chiropractic or physical therapy
Prompt attention to lameness or other problems that may cause compensatory back issues

Physical conditioning:

Maintaining appropriate body condition (not overweight)
Building and maintaining strong topline musculature
Varied work preventing repetitive strain

Living with a Horse with Kissing Spine

Owners of horses diagnosed with kissing spine face ongoing management responsibilities:

Regular monitoring: Staying alert for signs of discomfort and addressing issues promptly before they escalate.

Consistent training approach: Maintaining emphasis on correct posture and engagement rather than allowing poor movement patterns.

Management modifications: Accepting necessary changes in work intensity, discipline, or expectations.

Financial commitment: Ongoing costs for specialized care including veterinary treatment, bodywork, potentially custom equipment.

Realistic expectations: Understanding that while many horses remain useful and comfortable with proper management, some may have permanent limitations or eventual need for retirement.

Quality of life assessment: Regularly evaluating whether the horse maintains acceptable comfort and soundness for continued work, and making difficult decisions if quality of life becomes compromised.

Conclusion

Kissing spine (overriding dorsal spinous processes) represents a common and clinically significant cause of back pain in horses, occurring when the bony projections extending upward from vertebrae become too close together or make contact, causing pain, inflammation, and functional impairment. This condition affects horses across all breeds and disciplines, though certain conformational factors, training methods, and work demands increase risk.

Clinical signs range from subtle performance decline to obvious pain and dangerous behavioral changes, though the correlation between radiographic severity and clinical signs is imperfect. Diagnosis requires combining clinical examination findings with diagnostic imaging, particularly radiographs and ideally nuclear scintigraphy, to identify affected sites and assess disease activity.

Treatment approaches span from conservative management including rest, rehabilitation, medication, physical therapy, and management modifications, to more aggressive interventions including corticosteroid injections, extracorporeal shockwave therapy, and surgical procedures like interspinous ligament desmotomy or partial ostectomy. Many horses, particularly those with mild to moderate disease diagnosed early, respond favorably to conservative treatment, though some require surgical intervention.

Prognosis varies but with appropriate treatment and ongoing management, 50-80% of affected horses can return to some level of work, though permanent modifications may be necessary. Complete return to previous high-level athletic performance is possible but not guaranteed, and realistic expectations are essential.

Prevention strategies emphasizing correct training methods that promote proper back engagement, maintenance of strong topline musculature, meticulous saddle fitting, and appropriate conditioning offer the best approach to reducing kissing spine incidence.

For horses diagnosed with this condition, success requires commitment to comprehensive treatment, patient rehabilitation, ongoing attention to management details, and willingness to modify expectations when necessary. With informed, dedicated care, many horses with kissing spine can continue comfortable, useful careers while maintaining good quality of life.