Unpacking Posture – Part 1

Beyond stance: A closer look at static postural assessment in horses

by Kevin K. Haussler, DVM, DC, PhD

in collaboration with Caroline Lindsay, BSc(Hons), PGCert, MSFC Dip, AdvCertVPhys, CertEdVPT; and Alissa Mayer, BSc(Equine), EHSE-C

In our pursuit to identify better methods for assessing equine health, posture is a fundamental characteristic that can reflect the horse’s overall well-being and performance. From the graceful stance of a horse grazing in the pasture to the poised elegance of an athlete, posture plays a pivotal role in the life of every horse. In Part 1 of this blog, we will explore the concept of static posture in horses, outline a few postural assessment methods, and describe some of the factors that may contribute to poor posture. In Parts 2 and 3, we will look at dynamic posture and horse-rider interactions.

Defining posture

Posture is characterized by the position and alignment of the body segments in relation to their surroundings and the force of gravity. Static posture refers to the body position while at rest or during quiet activities. A horse’s overall posture is a reflection of its mental status and the sensorimotor integration required to resist the effects of gravity and coordinate biomechanical and neuromuscular interactions within different body segments and the ground.

Because posture is constantly changing depending on what the body is doing at a specific point in time, posture is as much about organization of the body as it is about the observable position of the body. For the purposes of this 3-part series, we define posture as follows:

  • Posture: body position in response to the force of gravity and sensorimotor integration
  • Static posture: body position as observed at rest, while unridden or ridden
  • Dynamic posture: body position as observed while in motion
  • Ideal posture: a theoretical body position that is judged to be the standard for a specific individual given their conformation and the surrounding external environment
  • Deviated posture: any observed change in body position that is judged to be different from the perceived ideal posture

Conformation versus posture

While conformation and posture are distinct concepts, they are closely intertwined and influence each other in significant ways. Conformation refers to the physical structure and proportions of a horse’s body and encompasses traits such as bone structure, muscle development, limb length joint angulation, and overall body proportions. Conformation is largely predetermined by genetics and remains relatively static throughout the horse’s life. It cannot be readily changed or influenced.

In contrast, posture is dynamic and responsive, constantly adapting to the horse’s activities, environment, and physical condition. Posture is a functional attribute that can be readily modified in most horses. It reflects the ongoing interaction between muscles, joints, and sensory feedback systems that are required to maintain stability and balance while standing, moving, or performing tasks.

Conformation and posture contribute to the overall health, soundness, and performance of the horse. A horse with well-balanced conformation is better equipped to maintain ideal posture, promoting biomechanical efficiency, joint health, and overall comfort. Conversely, postural issues can exacerbate conformational faults, leading to soft tissue injuries, stiffness, and altered movement patterns.

Postural assessment

Postural assessment provides insights into the horse’s ability to resist the effects of gravity on the different body segments and to maintain its center of mass within a base of support. Posture is an observed clinical sign (like body condition score) that we, as external observers, judge to be “good” or “bad”. However, we may not fully understand what the underlying cause of the observed posture is or if it is a protective or detrimental response within an individual horse.

Assessing static posture involves a comprehensive evaluation of specific musculoskeletal attributes that reflect the horse’s neuromuscular status at a specific point in time. The horse should be evaluated while standing quietly on a loose lead, with minimal interference. To assess postural consistency, the horse is asked 3 or 4 times to take a few steps forward then stopped to assess the repeatability in limb placement and weight bearing as indicators of their preferred (or habitual) stance (i.e., static posture.)

Postural tendencies or patterns are noted as the horse’s interaction with its environment and the handler are constantly changing. Observing the horse from various angles also provides valuable insights into their static posture.

Here are a few attributes to consider when assessing a horse’s posture:

  • Head and neck carriage – head height, curvatures, head and neck position, axial alignment, left-right asymmetries in muscle tone or development
  • Trunk – dorsal midline contour (lordosis, kyphosis), ventral midline contour (body condition, fitness), axial alignment (scoliosis), left-right symmetry
  • Pelvis – croup angle, left-right symmetries in the height or craniocaudal position of the tubera coxae
  • Tail – tail carriage, axial alignment
  • Limbs – placement, weight bearing, joint angulations, vertical alignment, axial rotation
  • Global – overall proportions and relationship of body segments

“When assessing posture, knowing the breed and the type and level of conditioning is essential to determine if what you expect to see is what you actually see.”   – Caroline Lindsay

Ideal posture

Ideal posture is characterized by a harmonious alignment of various anatomical structures, reflecting ideal balance, symmetry, and musculoskeletal health. Static posture is best evaluated when the horse has a relaxed and calm demeanor. Ideally, the horse’s head is carried in a relaxed, neutral position, with the poll either level or slightly higher than the withers. The neck forms a gentle arch from the poll to the base, without excessive flexion or extension. When viewed from the side, the dorsal trunk contour follows a natural curvature from the withers to the croup, with the thoracic and lumbar vertebrae relatively straight and slight flexion noted at the lumbosacral junction. The pelvis has symmetrical left-right alignment when viewed from behind. The limbs are positioned uniformly and squarely under the body, with the limb segments aligned vertically from the shoulder or hip to the ground. The limbs and hoofs should be axially aligned without overt internal or external rotation.

“Posture, as an organizational process, is not the problem – the restriction on ideal posture is the problem.”   Alissa Mayer

Factors to consider

Posture can be influenced by many intrinsic factors such as mental status, fatigue, pain, joint flexibility, and balance. Conformational defects often have a direct impact on posture. Muscle development is considered a conformation trait and should be symmetrical throughout the axial skeleton and limbs. Muscle tone reflects integration of the sensorimotor system. Muscle tone and development are potential indicators of postural deviations. Athletic fitness, body condition, and injury status all have direct influences on posture.

Behavioral influences on static posture include boredom, fear, anxiety, and conditioned responses. Young or untrained horses may not have a well-developed sense of body awareness or joint position, which directly impacts posture. Different horse breeds often have unique conformational and postural characteristics that make certain breeds more adept in specific athletic disciplines. Extrinsic factors include management (e.g., stall confinement) and training practices. Uneven terrain and different types of ground surfaces directly impact the way a horse senses its balance and how it stands.

Pain and posture

Pain has a significant impact on posture. When experiencing discomfort or injury, horses may adopt compensatory body movements or postures to alleviate pain or pressure on affected tissues. These alterations in movement patterns or posture are often temporary and self-resolve but can persist long past the initial pain insult or tissue injury. Persistent postural deviations can further exacerbate musculoskeletal imbalances, leading to a vicious cycle of pain and increased risk of additional injury. Understanding the relationship between pain and posture is crucial for effective management and rehabilitation strategies.

Asymmetry and posture

Asymmetry consists of functional and structural components, both of which have direct effects on posture. A structural asymmetry might include differences in the size, shape and angulation of the front hooves, which may affect how a horse stands or positions its front limbs. A functional asymmetry might relate to a horse being stronger or more flexible on one side of its body than the other, which will likely also impact how a horse bears weight or holds its body position.

To learn more about laterality vs asymmetry, watch our webinar at https://vetcompendium.org/catalog/laterality-or-is-it-just-asymmetry/

Postural deviations

Posture reflects the body’s constant adaptation to its external environment and the internal neuromuscular mechanisms that produce characteristic patterns in body positioning. Transient or inconsistent postural deviations are judged to be less clinically relevant as they likely reflect normal physiologic processes. Persistent postural deviations are characterized by repeatable or consistent alterations from what is judged to be ideal.

Many postural deviations are due to unconscious postural patterns (i.e., we are not aware that we are standing or sitting uneven). A horse may stand a particular way to avoid or unload painful areas or as an unconscious response. However, when we are reminded to sit up straight in the saddle, or when we ask the horse to assume a frame, it requires focused attention and a conscious effort to maintain these specific postures.

Effects of poor posture

Poor posture in horses can have far-reaching consequences, impacting their overall health, comfort, and performance. Altered weight bearing, guarding of painful regions, and overuse of adjacent body segments can lead to increased wear and tear on joints and soft tissues. Postural deviations contribute to discomfort, increased myofascial tone, decreased joint range of motion, compromised movement efficiency, and loss of performance. Over time, postural deviations increase the risk of joint disease, soft tissue injuries, and chronic pain syndromes.

In closing…

Static posture serves as a foundational element of assessing equine health and performance, influencing every aspect of a horse’s life and reflecting many aspects of each horse’s individual experiences. Understanding the causes and effects of poor posture provides valuable insights into the complex interplay between form and function. Through diligent observation and targeted interventions, we can strive to improve static posture in horses, promoting their well-being and helping them to achieve their full athletic potential.

Stay tuned for Part 2 Dynamic Posture and Part 3 Horse-Rider Interactions.

Is this your understanding of static equine posture or do you have a different perspective?

Do you always evaluate the horse’s static posture as part of your pre-treatment, whole-body assessment?

On May 30th at 3 pm MDT, join Dr. Haussler and his guest collaborators – veterinary physiotherapist, saddle fitter, and graduate sports therapist Caroline Lindsay and Certified Equine Hanna Somatics® Educator Alissa Mayer – to discuss the important topic of posture.

Registration at vetspine.org/community-gatherings/

Interested in learning more?

Resources

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Krueger K, Schwarz S, Marr I, Farmer K. laterality in horse training: psychological and physical balance and coordination and strength rather than straightness. Animals. 2022; 12: 1042. https://doi.org/10.3390/ani12081042

Lesimple C, Fureix C, De Margerie E, Sénèque E, Menguy H, et al. Towards a postural indicator of back pain in horses (Equus caballus). PLOS ONE 2012; 7: e44604. https://doi.org/10.1371/journal.pone.0044604

Merkies K, Alebrand J, Harwood B, LaBarge K, Scott L. Investigation into thoracic asymmetry in ridden horses. Comparative Exercise Physiology 2020; 16(1): 55-62. https://doi.org/10.3920/CEP190025

Sénèque E, Lesimple C, Morisset S, Hausberger M. Could posture reflect welfare state? A study using geometric morphometrics in riding school horses. PLOS ONE 2019; 14: e0211852. https://doi.org/10.1371/journal.pone.0211852