Understanding Compensation Patterns in Horses

and What to Do About Them

by Kevin K. Haussler, DVM, DC, PhD

Practitioners often talk about compensations and compensation patterns. However, they often offer very different definitions or explanations based on their individual perspectives and modes of assessment. In this blog, we will attempt to clarify, and will delve into the different ways the body reacts to injury or disease, whether those responses are good or bad, and what we can do to help manage them.

Defining compensation

Injuries or disease processes are often localized to a specific tissue, location, or body system (i.e., pathoanatomic diagnosis). Compensations refer to the behavioral, neurophysiologic, and biomechanical adjustments that horses make in response to the initial or inciting cause of pain, injury, or dysfunction. Depending on whether the disease is a slow, progressive, subclinical process or has an acute onset with overt clinical signs, our ability to clearly identify the initial inciting cause versus the myriad of secondary responses varies widely and can be very difficult at times.

Responses to injury

The body has many different mechanisms for defending against injury and disease. There are also many ways that the body responds to different types of injuries and disease processes. Here are a few typical responses to injury or disease:

Acute onset and quick resolution

This response involves a sudden onset of clinical signs, followed by rapid improvement or resolution either by normal healing processes (e.g., inflammation) or with appropriate treatment. A horse sustains a minor skin laceration or surgical procedure and exhibits acute lameness. With rest, anti-inflammatory medication, and supportive care, the lameness resolves within a few days, and the horse returns to normal activity.

Recurrent injury with recurrent signs

In this scenario, the horse experiences repeated episodes of injury or exacerbation of a pre-existing condition, leading to recurrent signs. A horse with a history of intermittent lameness due to proximal suspensory disease may experience recurrent bouts of pain and stiffness, requiring periodic treatment and exercise modification to help alleviate the clinical signs.

Chronic disease with limited or no resolution

Chronic diseases are characterized by long-lasting or persistent signs that may have limited or no resolution despite treatment. Equine metabolic syndrome is a metabolic disorder characterized by insulin dysregulation, obesity, and an increased risk of laminitis. Management involves dietary modifications, weight management, and controlled exercise, but there is no cure, and the condition persists throughout the horse’s life.

Chronic disease with secondary effects

Chronic diseases can lead to secondary effects or complications affecting other body systems or functions. Osteoarthritis is a chronic degenerative condition characterized by progressive cartilage degradation, inflammation, and changes in joint structure. As the disease progresses, treatment becomes less effective while pain and dysfunction in other body regions becomes clinically evident, which initiates disease processes of their own.

Some of these secondary responses (i.e., compensations) include the following:

  • Muscle imbalances, weakness, or hypertrophy due to altered movement patterns
  • Overuse of adjacent or regional articulations, which precipitates osteoarthritis in additional joints
  • Tendon and ligament strain from altered joint mechanics and instability
  • Development of chronic pain syndromes and unwanted behavior

Resolution of the initial injury but persistent long-term complications

In some cases, the primary injury or condition resolves, but secondary effects or complications persist. While a fracture may have healed completely and the surgical repair considered a success, the associated support-limb laminitis contributes to a long list of secondary issues that persist for the life of the horse.

These examples illustrate the diverse range of responses to injury in horses, highlighting the importance of thorough diagnosis, appropriate treatment, and ongoing management to address both primary and secondary effects of injury and disease.

Adaptive versus maladaptive responses

Adaptation involves the horse’s natural response to maintain functionality despite injury or discomfort. For example, if a horse experiences soreness in its hindquarters, it may shift more weight onto its forelimbs to relieve pressure on the hind end. However, if this compensatory pattern persists or becomes exaggerated, it is considered a maladaptive response. Maladaptation refers to the development of abnormal movement patterns or postures that exacerbate the underlying issue and may cause secondary problems in other areas of the body.

Adaptation involves protective responses such as guarding the affected area, reducing weight-bearing, or avoiding certain movements to minimize discomfort. These adaptations are usually temporary and resolve once the underlying issue improves. Normal responses to pain or injury typically have minimal impact on the horse’s overall function and performance, as they are geared towards self-preservation and healing.

Maladaptation is a pathologic process that produces persistent compensations that do not self-resolve and often initiate additional injury or disease in adjacent body regions. Maladaptive changes can have a substantial negative impact on the horse’s biomechanics, function, and performance.

Contributing factors

Several factors can contribute to the development of compensation patterns in horses:

  • Conformational deviations: Structural deviations such as limb asymmetry, spinal misalignment, or uneven hoof growth can predispose horses to compensatory patterns.
  • Hoof imbalances: Asymmetries in hoof size and shape are often associated with abnormal loading patterns or differences in foot flight, which can contribute to pain and dysfunction in other body regions.
  • Poor saddle fit: Ill-fitting saddles can create pressure points or restrict movement, prompting the horse to compensate to alleviate discomfort.
  • Imbalanced training: Overtraining certain muscle groups while neglecting others can lead to muscular imbalances and compensatory movements.
  • Rider influence: Inappropriate rider position, excessive rein pressure, or inconsistent aids can contribute to compensatory responses in the horse.

Effects on posture, locomotion, and ridden exercise

Compensation patterns can manifest in various ways, affecting the horse’s posture, locomotion, and performance under saddle:

  • Postural changes: Compensation may result in asymmetrical muscling, uneven weight distribution, or alterations in spinal alignment, leading to a visibly unbalanced or crooked appearance.
  • Altered locomotion: Compensatory movements can affect the horse’s gait, causing irregularities such as shortened strides, stiffness, reluctance to bend or flex, or resistance to certain movements.
  • Ridden exercise: Horses with compensation patterns may struggle with collection, engagement, or transitions, hindering their ability to perform certain maneuvers or exercises effectively.

Managing compensation

Knowing when to treat and try to remove compensation patterns in horses depends on the severity of the issue, its impact on the horse’s well-being and performance, and the potential for further complications.

Here are examples of scenarios where intervention may be warranted:

  • Significant pain or dysfunction: If the horse is experiencing significant pain or dysfunction due to the compensation pattern, intervention is necessary to alleviate discomfort and prevent further deterioration.
  • Impact on performance: When compensation patterns interfere with the horse’s ability to perform certain tasks, such as riding exercises or competitive activities, addressing the underlying issues is essential to optimize performance and prevent injury.
  • Risk of secondary problems: If the compensation pattern increases the risk of developing secondary issues, such as muscle imbalances, joint strain, or postural abnormalities, proactive intervention can help prevent these complications from arising.
  • Chronic or progressive conditions: In cases where the underlying condition causing the compensation pattern is chronic or progressive, early intervention can help mitigate its effects and improve long-term outcomes for the horse.
  • Owner or rider concerns: If the owner or rider expresses concerns about the horse’s comfort, movement, or performance related to the compensation pattern, addressing these concerns through appropriate treatment and management strategies is needed.

Situations where it may be best to refrain from immediate action include the following:

  • Minor or self-resolving issues: If the compensation pattern is minor and likely to resolve on its own with rest, time, or conservative management, immediate intervention may not be necessary.
  • Natural adaptive responses: In some cases, compensation patterns may be natural adaptive responses that help the horse cope with temporary discomfort or minor injuries without causing significant impairment.
  • Low impact on function: If the compensation pattern has minimal impact on the horse’s function, comfort, or performance, it may be acceptable to monitor the situation without immediate intervention, especially if the horse remains sound and comfortable.
  • Underlying cause not identified: If the underlying cause of the compensation pattern is unclear or difficult to identify, it may be prudent to conduct further diagnostic evaluations before initiating treatment to ensure targeted and effective intervention.
  • Risks of over-treatment: In situations where the risks of over-treatment, such as excessive interventions or invasive procedures, outweigh the potential benefits, a conservative approach focused on monitoring and supportive care may be more appropriate.

The decision to treat and remove compensation patterns in horses should be based on careful consideration of the severity of the issue, its impact on the horse’s well-being and performance, and the potential risks and benefits of intervention. While prompt treatment may be necessary in certain situations, there are also instances where a watchful waiting approach or conservative management may be more suitable. Consulting with a qualified veterinarian or equine healthcare professional can help determine the most appropriate course of action for each individual case.

In closing…

Compensation patterns in horses are complex behavioral, biomechanical, and neurophysiologic responses to pain, injury, or imbalances in the musculoskeletal system. While initially adaptive, prolonged or exaggerated compensation can lead to maladaptive responses characterized by chronic pain and dysfunction. By understanding the causes, effects, and methods for diagnosis and treatment of compensation patterns, horse owners and professionals can work together to ensure the well-being and optimal function of their equine partners.

What is your definition of a compensation?

Are all compensations good? Or bad?

How can you tell if a compensatory issue is adaptive or maladaptive?

What are the most effective methods for managing adaptive responses to pain or tissue injury?

How fast do compensatory issues typically resolve?

Read our blog, then join Dr. Haussler and his guest collaborators on June 27, 2024 at 11 am MDT for a conversation about this topic. Guests are respected trainers Jillian Kreinbring, MS and Veronika von Rohrscheidt, DVM.

Interested in learning more?

Resources

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Greve L, Dyson S. The horse-saddle-rider interaction. Vet J 2013; 195: 275-281. DOI: 10.1016/j.tvjl.2012.10.020

Parkes RSV, Witte TH. The foot–surface interaction and its impact on musculoskeletal adaptation and injury risk in the horse. Equine Vet J 2015; 47: 519-525. DOI: 10.1111/evj.12420

Schöllhorn WI, Peham C, Licka T, et al. A pattern recognition approach for the quantification of horse and rider interactions. Equine Vet J Suppl 2006: 400-405. DOI: 10.1111/j.2042-3306.2006.tb05576.x

Serra Bragança FM, Hernlund E, Thomsen MH, et al. Adaptation strategies of horses with induced forelimb lameness walking on a treadmill. Equine Vet J 2021; 53: 600-611. DOI: 10.1111/evj.13344

Spoormakers TJP, St. George L, Smit IH, et al. Adaptations in equine axial movement and muscle activity occur during induced fore- and hindlimb lameness: A kinematic and electromyographic evaluation during in-hand trot. Equine Vet J 2023;55:1112-1127. DOI: 10.1111/evj.13906.