For most veterinary students, the first encounter with fascia happens in an anatomy lab, and it is not a memorable one. The tissue gets pushed aside so the structures underneath can be identified, labeled, and memorized for the exam. Muscles, nerves, bones, and vessels all had clear origins, insertions, and functions worth knowing. Fascia seemed to have none of those things. It was everywhere, it had no obvious boundaries, and it was always in the way.
That early dismissal has had lasting consequences for how pain is assessed and treated in clinical practice. As fascia finally receives serious attention in mainstream medicine, veterinary practitioners working in integrative rehabilitation and physical medicine have an opportunity to lead rather than follow. Understanding what fascia is, how it behaves under stress, and why it matters clinically is foundational to that work.
What Fascia Actually Is
The reason fascia resists simple description in anatomy lab is that it does not follow the same organizational logic as the structures surrounding it. It forms an uninterrupted network that runs through, inside, and alongside nearly every structure in the body. Identifying where it begins and ends is not possible in the way it is for a muscle or a nerve, because it does not begin and end. It continues.
Anatomically, fascial tissue exists in distinct layers with different properties. Superficial fascia sits just beneath the skin and consists of loosely interwoven collagen and elastic fibers embedded within a gelatinous extracellular matrix rich in glycosaminoglycans, proteoglycans, and polysaccharides. This layer does not remain at the surface. As Bordoni and Zanier describe, it permeates the entire body, enveloping organs and forming the stroma, neurovascular branches, and the fascia of muscle districts before meeting the deep fascia. The various layers communicate through a microvacuolar system composed of the same structural elements as the superficial fascia, forming a microscopic web of vessels and nerves in varying directions that is highly deformable under load.
Deep fascia surrounds muscles, nerves, vessels, and bone. It is generally more fibrous and dense, with collagen fibers arranged in a more parallel orientation and substantial concentrations of hyaluronic acid that allow layers to glide relative to one another during movement. When that gliding capacity is lost, the consequences extend well beyond the local tissue.
The Fibroblast: The Cellular Engine of Fascial Function
The fibroblast is the primary cellular constituent of fascial tissue, and its behavior is considerably more dynamic than the term connective tissue cell might suggest. When fascial tissue lengthens, fibroblasts flatten and expand, increasing their surface area in a way that allows the tissue to sustain tension without difficulty. The cytoskeleton of the fibroblast, composed of microtubules, actin filaments, and intermediate filaments, enables rapid adaptation to compressive and tensile forces. Actin’s particular flexibility allows for near-instantaneous cytoskeletal reorganization in response to mechanical change, meaning that fascial tissue is actively responding to the forces placed on it in real time.
Beyond their structural role, fibroblasts function as growth factor factories. They secrete insulin-like growth factors, fibroblast growth factors, hepatocyte growth factor, interleukins, and nitric oxide. This output positions the fibroblast as an active participant in inflammation, tissue remodeling, and healing rather than a passive structural element. Cannabinoid receptor CB1, primarily associated with the nervous system, is also present in fascial tissue and in fibroblasts, particularly near the neuromuscular junction. This distribution is thought to contribute to the management of pain and inflammation originating within fascial tissue as it undergoes continuous remodeling throughout the day.
These findings have significant implications for how practitioners understand both the onset of fascial dysfunction and its resolution.
Fascia as a Source of Pain
In a healthy animal, the fascial system fulfills its function without drawing attention to itself. It distributes mechanical forces across the body during movement, protects nerves carrying proprioceptive signals from the periphery to the brain, moves fluids, and modulates pressures in organs, vessels, muscles, and joints. The system works as a coordinated whole because it is structurally continuous and physiologically integrated.
When fascia becomes tense, thickened, or restricted following injury, chronic inflammation, postural imbalance, or sustained mechanical overload, that integration is disrupted. Restricted fascia inhibits movement, slows fluid distribution, compresses nerves and blood vessels, and generates discomfort that spreads along its routes rather than remaining confined to a single joint or muscle. This is one reason patients sometimes present with pain that appears disproportionate to what imaging reveals. The structural finding may be accurate but incomplete. The broader fascial system is frequently involved in ways that imaging alone does not capture.
The body is not organized like a machine in which individual components fail independently. Dogs, cats, and horses exist as systems where signaling and load transfer operate across multiple levels simultaneously. When one region of the fascial network loses its capacity to glide, transmit force, or support circulation, the effects are rarely local.
The Thoracolumbar Fascia and Its Clinical Significance
Among the fascial structures that have received the most research attention in recent years, the thoracolumbar fascia stands out for its complexity and its clinical relevance to conditions commonly encountered in veterinary practice.
The thoracolumbar fascia is a multilayered aponeurotic structure that plays a central role in load transfer through the spine and pelvis. Its layers unite to form what functions as an endogenous back brace in the caudal back and pelvis, contributing to both static postural support and dynamic movement. It assists with respiration and helps distribute mechanical forces across the lumbopelvic region in ways that protect individual spinal segments from excessive strain.
What makes the thoracolumbar fascia particularly relevant to pain medicine is its innervation. Research by Willard and colleagues has documented a high density of sympathetic nerve fibers within this structure, a finding with direct clinical implications. The presence of sympathetic innervation suggests that fascial disorders may be influenced by autonomic nervous system activity, which may help explain why animals experiencing chronic pain often show signs of autonomic dysregulation alongside their musculoskeletal presentations. Willard notes that stimulation of intrafascial sympathetic afferents through manual medicine techniques may trigger modifications in global autonomic nervous system tone as well as in local circulation and matrix hydration.
The thoracolumbar fascia also plays a role in proprioception. Research has documented a mutually antagonistic relationship between low back pain and lumbar proprioception, where the presence of pain is associated with reduced proprioceptive signaling and inhibition of proprioceptive input intensifies pain sensitivity. Rehabilitative strategies that improve proprioception therefore address not just sensorimotor function but pain itself. Understanding the proprioceptive capacity of the thoracolumbar fascia has direct implications for how rehabilitation programs are designed and targeted.
Hair Coat Patterns as a Diagnostic Window
Clinical observation of fascial dysfunction often begins before palpation. In cats and dogs, abnormal hair coat patterns including areas of persistently flattened or erect fur can correspond directly to regions of underlying fascial restriction. These coat changes frequently align with postural asymmetries and areas of palpable tension, thickening, or tenderness within the myofascial network.
A case report documenting a thirteen-year-old feline patient treated with medical acupuncture illustrates this clearly. Before treatment, the cat showed paraspinal fur flattening and banding across the cervical, caudal scapular, and mid-truncal regions. Subsequent radiographs confirmed osteoarthritis of the hips and lumbosacral junction. Following three sessions of medical acupuncture, improvements were observed in hair coat pattern, posture, and overall mobility. The correspondence between external coat findings and underlying fascial and structural pathology in this case reflects a pattern seen across many patients when assessment is performed systematically and with attention to the whole animal.
Palpation remains central to fascial assessment. Identifying regions of heat, tension, restriction, thickening, and tenderness across the myofascial network from head to tail and topline to toe provides a clinical picture that imaging and symptom reporting alone cannot generate. Warmth in a region may indicate active inflammation, but it may also signal circulatory shifts driven by cellular signaling and autonomic dysregulation in tissue that has lost normal autoregulatory capacity. Distinguishing between these requires the kind of careful hands-on assessment that integrative rehabilitation training develops.
Why Integrative Rehabilitation Approaches Address Fascia Effectively
Integrative veterinary therapies interact with the fascial system through mechanisms that are increasingly well characterized in the research literature. Acupuncture has been shown to influence fascial stiffness and neuromuscular signaling, with evidence supporting its effects on both local tissue properties and broader sensorimotor communication. Massage therapy reduces fascial thickness and stiffness while improving circulation within connective tissue layers. Stretching reduces deep fascial stiffness through mechanisms involving fibroblast remodeling and changes in hyaluronic acid distribution. Photomedicine and extracorporeal shockwave therapy reduce pain and improve patient outcomes in fascially mediated conditions including plantar fasciitis.
What these approaches share is clinically significant. They do not destroy tissue, do not permanently alter anatomy, and carry a safety profile that compares favorably with surgical intervention in the vast majority of cases presenting with pain and movement disorders rooted in fascial dysfunction. They work with the body’s physiology, restoring normal communication between nerves, muscles, and connective tissues rather than replacing or removing structures. For patients experiencing chronic pain, postural dysfunction, or functional limitations with a fascial component, this is not a secondary consideration. It is often the most direct and effective path toward recovery.
Fascia cannot be treated in isolation from the system it is part of, and integrative rehabilitation does not attempt to do so. Acupuncture influences fascial stiffness while simultaneously modulating pain processing at spinal and supraspinal levels. Manual therapy addresses local tissue restriction while stimulating afferent input that recalibrates sensorimotor reflexes. Photomedicine reduces inflammation in fascial tissue while supporting cellular repair processes that determine how the tissue remodels after injury. The approaches are not interchangeable, and their combined application in a well-designed multimodal protocol reflects the systemic nature of fascial dysfunction itself.
What This Means for Practitioners at CuraCore Canada
For veterinary professionals pursuing training in integrative rehabilitation, medical acupuncture, or physical medicine, a working knowledge of fascial anatomy and physiology is not background information, it’s a clinical framework. The patients most likely to benefit from integrative approaches are frequently those whose pain presentations do not fit neatly into structural diagnoses, whose imaging findings do not fully account for their functional limitations, or whose responses to conventional management have been incomplete. In many of those cases, fascial dysfunction is a central part of what is happening.
CuraCore Canada‘s programs in integrative rehabilitation and medical acupuncture are designed to equip practitioners with the scientific foundation and clinical skills to assess and address these presentations effectively. Understanding how fibroblasts respond to mechanical stimuli, why the thoracolumbar fascia matters in both pain and proprioception, and how integrative techniques influence fascial tissue at a physiological level transforms the way a clinician approaches assessment. The ability to read posture, interpret coat changes, systematically palpate the myofascial network, and select interventions based on an understanding of the underlying mechanisms is what separates integrative rehabilitation practiced at a high level from a collection of techniques applied without a unifying framework.
Fascia connects everything in the body. In practice, understanding it connects the assessment to the treatment and the treatment to the outcome.
Read the Original Article
This piece draws substantially from the work of CuraCore founder Narda G. Robinson, DO, DVM, MS, FAAMA, originally published in Veterinary Practice News. For a deeper examination of fascial anatomy, the thoracolumbar fascia, and the clinical case of Kayla the feline patient, the full article is available at Veterinary Practice News: “To Fix Pain, Don’t Forget the Fascia.”