Kissing Spines

Kissing spines sounds like an unusual condition, and the name can be misleading until you understand what's actually happening in the horse's back. The technical name is overriding dorsal spinous processes, which describes vertebrae whose pointy spinous processes have become so close together that they actually touch or override each other. When these bony projections come into contact, they can cause irritation, inflammation, and pain that radiates through the back, affecting the horse's movement, performance, and quality of life.

Kissing spines are surprisingly common in horses, particularly performance horses, older horses, and those with certain conformation characteristics. Some horses are predisposed by the shape of their spine or the length of their vertebral processes. Others develop kissing spines as a consequence of work, poor conformation, or back pain from other sources. The condition affects horses across all disciplines, though it's especially common in jumpers, dressage horses, and barrel racers—sports where the horse's back bears significant stress and must move in specific ways.

The severity of kissing spines varies dramatically from horse to horse. Some horses show only subtle lameness or resistance that owners might attribute to attitude or training problems. Others develop obvious problems that prevent work or cause significant discomfort. The pain level doesn't always correlate with how severe the condition appears on radiographs—some horses with extensive kissing spines remain relatively comfortable with management, while others with apparent mild involvement experience significant pain. Understanding that severity exists on a spectrum helps you recognize when your horse might have a problem.

Back pain often goes unrecognized in horses because owners attribute behavioral or performance problems to training issues rather than physical discomfort. A horse that becomes reluctant to jump, refuses to engage the hind end, or resists collection in dressage might actually be experiencing back pain from kissing spines rather than being stubborn or lazy. This means many horses suffer with the condition longer than necessary because the underlying cause isn't identified. Early recognition and appropriate management can prevent the condition from worsening and allow the horse to return to comfortable function.

Understanding kissing spines helps you recognize when your horse's behavior changes, what diagnostic approach your veterinarian might take, and what treatment options are available. This guide covers the anatomy of the horse's back, how kissing spines develop, what signs suggest your horse might have the condition, how vets diagnose it, and what management and treatment strategies help horses with kissing spines continue useful careers.

Kissing spines develop through a combination of anatomical factors and biomechanical stress that causes the vertebral spinous processes to gradually come closer together. The primary cause is structural—some horses are simply born with vertebrae that are predisposed to overriding. Vertebral processes vary in length, angle, and spacing between individual horses. Horses with longer spinous processes, particularly those that angle slightly toward each other, are at greater risk for developing kissing spines over time. This structural predisposition doesn't guarantee the condition will develop, but it increases vulnerability.

Conformation contributes significantly to kissing spines risk. Horses with upright, short backs are at higher risk than those with long, sloping backs because the vertebral mechanics differ. Horses with poor hind-end engagement or weak hindquarters develop compensatory movement patterns that stress the back incorrectly, encouraging kissing spines to develop. Horses with excessive lordosis (sway back) or kyphosis (hunter's bump) have altered spinal geometry that increases pressure on the dorsal spinous processes. Tall horses with long backs and heavier horses placing more weight through their spines are also at increased risk.

Work and training significantly influence whether kissing spines develop in predisposed horses. Repetitive work that stresses the back in specific patterns accelerates development. Young horses worked too intensely before their backs fully mature are at risk, as are horses ridden by heavy riders whose weight stresses immature or weak backs. Jumping and dressage horses doing advanced collection and jumping movements place significant stress on the back. Barrel racers turning hard place rotational stress through vertebrae. Even saddle fit plays a role—saddles that don't distribute weight evenly or rest inappropriately on the horse's back contribute to uneven pressure and microtrauma accumulating over time.

Back pain from other sources sometimes triggers kissing spines development. Horses with sacroiliac joint problems, hip pain, or hock arthritis often develop secondary back pain and altered movement patterns that stress the dorsal spinous processes. This means treating the primary cause of back pain becomes important for preventing kissing spines from worsening. Weak abdominal and back muscles that fail to support the spine properly allow vertebrae to settle into positions that encourage overriding. Young horses with underdeveloped muscles and older horses with age-related muscle loss are both vulnerable.

Trauma can occasionally trigger kissing spines development. A horse that falls, gets struck in the back, or experiences severe trauma sometimes develops inflammation in that area that heals into kissing spines. However, most kissing spines develop gradually from the cumulative stress of conformation, work, and biomechanical factors rather than from single traumatic events. Age-related changes contribute as ligaments lose elasticity, cartilage wears, and the spine naturally loses some of its shock-absorbing capacity. Older horses with kissing spines sometimes have had the condition for years without significant problems, then develop symptoms as additional age-related changes compound the stress.

Kissing spines often present subtly, which is why many horses suffer with the condition undiagnosed for months or years. The earliest sign is often decreased willingness to engage the hind end or collect the back. You might notice your horse becomes reluctant to round his back under saddle, preferring to hollow instead. He might resist transitions, be unwilling to move forward into contact, or show less enthusiasm for work. These changes might seem like training issues or attitude problems rather than physical discomfort, which is why kissing spines frequently goes unrecognized initially.

Lameness or altered movement patterns often accompany kissing spines, though not always obviously. The hind limbs sometimes show reduced engagement or the horse moves with shorter strides in the hind end. Front-end lameness sometimes occurs because the horse compensates for back pain by shifting weight forward. Some horses develop a choppy, restricted gait compared to their normal movement. The lameness might be bilateral and symmetrical, making it harder to detect than one-sided lameness. Some horses only show lameness at certain gaits or under specific work conditions like jumping or collection.

Resistance and behavioral changes frequently accompany kissing spines. A horse might buck, rear, or refuse to move forward, particularly when asked to engage the back. He might shy excessively, becoming girthy or resistant to mounting because those actions stress the painful area. Some horses show unexplained aggression or attitude changes that don't respond to training changes. Dressage horses might refuse certain movements or show inconsistent performance. Jumpers might become reluctant to jump or lose enthusiasm. What looks like a discipline-specific problem or training issue actually reflects pain when kissing spines is present.

Physical signs help identify kissing spines, though they're not always obvious on visual inspection. Some horses show a slight depression or unusual conformation in their back over the affected area. Muscle tension or asymmetry along the back sometimes appears, with one side more muscled than the other as the horse favors the opposite side. When you palpate the back firmly, pressing along the spinous processes, a horse with kissing spines might show pain or sensitivity in the affected area. However, some horses with significant kissing spines show no obvious physical signs on casual inspection.

Performance changes are often the first sign owners recognize. A horse previously willing and smooth suddenly becomes stiff, reluctant, or uncooperative. Jumpers lose smoothness or consistency. Barrel racers resist turns. Trail horses become reluctant to move forward. Dressage horses show loss of quality in movements that previously came easily. These changes sometimes happen acutely but often develop gradually—the horse progressively loses enthusiasm and quality until performance has noticeably declined.

Progression depends on whether the condition is addressed. Unmanaged kissing spines typically progress, with pain increasing and movement becoming more restricted as inflammation builds and the horse develops compensatory movement patterns. A horse undiagnosed for years might eventually develop such restricted, painful movement that work becomes impossible. In contrast, horses diagnosed and appropriately managed often stabilize, maintaining reasonable function. Some horses improve with aggressive treatment and management. Emergency signs are uncommon but include sudden severe back pain with inability to move comfortably, which warrants immediate veterinary evaluation.

Diagnosing kissing spines requires a systematic approach combining physical examination, observation of movement, and imaging. Your veterinarian begins by observing your horse in motion at various gaits and under saddle if possible, looking for movement quality and any signs of lameness or restricted engagement. They perform a detailed physical examination including palpation of the back, checking for pain or sensitivity. They evaluate the horse's flexibility, hind-end engagement, and movement quality during backing and turning. Flexion of the spine in various directions sometimes reproduces pain consistent with kissing spines.

Radiographs (X-rays) are the primary tool for confirming kissing spines diagnosis. High-quality lateral radiographs of the back show the spinous processes clearly, and the veterinarian can measure the space between processes and identify which vertebrae are overriding. Sometimes the dorsal spinous processes are so close they appear to be touching on radiographs. Additional radiographic views sometimes provide more detailed information about the exact nature and extent of involvement. Radiographs also reveal associated changes like arthritic changes in the facet joints or other back problems that might be contributing to the symptoms.

Ultrasound sometimes supplements radiographic findings, particularly for evaluating soft tissue involvement like ligament inflammation or damage between the spinous processes. Advanced imaging like CT (computed tomography) or MRI can provide exceptional detail about cartilage damage and soft tissue involvement, though these are less commonly used due to cost and availability. In many cases, high-quality radiographs combined with physical examination provide sufficient information to diagnose kissing spines and develop a treatment plan.

Treatment approaches vary based on the severity of the condition and how the individual horse responds. Conservative management is the first approach for many horses, involving rest from work, controlled exercise, and sometimes medication like NSAIDs to manage inflammation. Some horses respond well to conservative management, particularly if the condition is caught early before significant inflammation has developed. Rest allows inflammation to decrease, sometimes dramatically improving the horse's comfort.

More aggressive treatment options include therapeutic injections similar to joint injections, where substances that reduce inflammation and promote healing are injected into the ligaments and tissues around the affected vertebrae. These injections sometimes provide relief, particularly when combined with appropriate exercise and muscle-building work. Platelet-rich plasma (PRP) and stem cell therapies are increasingly used for kissing spines, with some horses showing excellent responses. These treatments promote healing rather than just managing symptoms.

Surgical options exist for horses with severe kissing spines that don't respond to conservative or injection-based treatment. Surgical removal of portions of the overriding spinous processes relieves the physical contact causing pain and inflammation. Several surgical techniques exist, with varying complexity and recovery time. Surgery for kissing spines is generally reserved for horses that have failed other treatments or have severely compromised function. Recovery involves stall rest, carefully controlled exercise progression, and rehabilitation typically lasting several months. Not all horses require surgery; many manage well with appropriate conservative or medical management.

Managing kissing spines involves a multifaceted approach combining rest, exercise modification, therapy, and potentially medication. During the acute phase when kissing spines is first diagnosed and particularly painful, rest from the activities causing pain provides immediate relief while inflammation settles. Complete stall rest isn't necessary and sometimes harms long-term recovery because it weakens the muscles that support the spine. Instead, controlled movement like hand-walking on soft footing maintains circulation, prevents stiffness, and allows gradual therapeutic benefit of light exercise.

Transitioning back to work requires a careful, progressive approach. Starting with very light work—short hand-walking sessions on soft footing—allows the horse to rebuild strength in supporting muscles without overstressing the painful area. As the horse improves, work duration and intensity gradually increase. Avoid the specific activities that caused pain until the horse is significantly stronger and pain has largely resolved. Some horses can return to work within weeks of diagnosis and appropriate treatment, while others require months of gradual rehabilitation.

Exercise modification plays a central role in long-term kissing spines management. Work that encourages proper engagement of the hind end and builds the muscular support system protecting the back helps the horse function better with kissing spines. Pole work, transitions, and exercises that strengthen the core without extreme collection are particularly valuable. Avoid or minimize work that causes pain or encourages the horse to hollow the back. For performance horses, this sometimes means adjusting training approaches or modifying demanding movements until the horse is stronger.

Saddle fit becomes critically important once kissing spines is diagnosed. A poorly-fitting saddle distributed weight unevenly and contributed to the problem, so addressing this is essential. Work with an experienced saddle fitter to ensure your saddle distributes weight evenly across the back without high points that concentrate pressure. Some horses benefit from saddles specifically designed for horses with back problems. The right saddle fit can make an enormous difference in comfort and recovery progression.

Muscle-building through appropriate exercise and therapy supports the spine and improves function. Once the acute pain phase resolves, progressive exercise that builds core strength helps the spine remain stable and properly supported. Some owners use physical therapy approaches like stretching, massage, or low-impact exercises to improve flexibility and strength. Chiropractic work sometimes helps, though evidence is variable and should be used alongside veterinary recommendations. These approaches complement rather than replace veterinary treatment.

Nutritional support during recovery focuses on anti-inflammatory nutrients and those supporting musculoskeletal health. Some veterinarians recommend joint supplements containing glucosamine, chondroitin, and hyaluronic acid for horses with kissing spines. Omega-3 fatty acids provide anti-inflammatory benefit. Appropriate weight management ensures the horse isn't overloaded, which stresses the back. Consistent, quality nutrition supports muscle development and tissue healing. Throughout management, work closely with your veterinarian and ideally a physical therapist or trainer experienced with back problems to ensure your horse is progressing appropriately.

Preventing kissing spines in predisposed horses involves addressing modifiable risk factors while recognizing that some horses have anatomical predisposition you can't change. Proper riding and training forms the foundation—ensuring the horse develops good balance, engagement, and muscular support prevents many back problems. Young horses particularly benefit from slow, progressive training that allows their backs to develop strength and stability before being asked to perform demanding movements. Building core strength through appropriate conditioning prevents many back problems from developing.

Saddle fit deserves emphasis because correct fit prevents back problems from developing. A saddle that fits properly distributes weight evenly, prevents pressure points, and allows the horse's back to move naturally. Investing in quality saddle fitting assessment prevents the chronic problems that develop from years of ill-fitting saddles stressing the back. Saddle fit becomes even more critical if your horse has structural predisposition to kissing spines.

Work modification based on your horse's individual capacity prevents many problems. Horses with conformation predisposing them to kissing spines benefit from work that builds strength and stability without excessive stress. Limiting intense collection work, heavy jumping, or repetitive rotation until the horse is properly conditioned protects vulnerable backs. This isn't about avoiding challenge but rather building capacity gradually through appropriate conditioning. Heavier riders might need to be particularly conscientious about gradual conditioning and saddle fit.

Regular veterinary evaluation catches developing problems before they become severe. Horses showing subtle signs of back pain should be evaluated with radiographs before problems advance. Horses with kissing spines on radiographs might never develop significant symptoms with proper management, but those unrecognized might progress to serious problems. Regular monitoring allows early intervention if symptoms develop.

The prognosis for kissing spines varies based on severity, how quickly treatment begins, and the individual horse's response. Mildly affected horses diagnosed early often show excellent responses to conservative management and maintain full function with appropriate riding. Moderately affected horses typically stabilize with treatment, allowing them to work at reasonable levels though sometimes with modifications. Severely affected horses might require surgery and longer recovery but can return to function afterward. Even horses that eventually can't be ridden sometimes maintain good quality of life with light work or retirement.

Long-term outlook with appropriate management is often favorable. Many horses with kissing spines live comfortable lives and maintain reasonable function for years after diagnosis. The key is early recognition, appropriate initial treatment, and long-term management that addresses both the condition and the factors contributing to it. Horses that develop kissing spines but are caught and managed well often function better than they did before diagnosis and treatment because the underlying back pain is addressed.