Spinal Biomechanics and Functional Anatomy 27
Jean-Marie D. Denoix
Knowledge of the normal functional behavior and mechanical
properties of the vertebral column is important to understand the
pathogenesis of back lesions, to identify the clinical manifesta-
tions of back pain, and to ensure a rational approach to physical
therapy. The purpose of this article is to present a synthesis of in
vivo and in vitro data obtained from different but complementary
investigations.

Physical Examination of Horses With Back Pain 61
Benson B. Martin, Jr and Alan M. Klide
The diagnosis of back pain is often a diagnosis of exclusion of
other problems in the face of poor performance. It requires careful
observation, thought, an open mind, and experience. The signs
of back pain can be extremely variable and range from subtle to
obvious. Obvious forelimb or hind limb lameness is not usually
a sign of back pain. The most common differential diagnosis may
be back pain secondary to degenerative joint disease of the hocks,
fetlocks, or stifle. These diseases can mimic signs of back pain
including lack of impulsion, shortening of the stride length, and
change in the stride character similar to those seen with back
pain.

Neuroanatomy and Neurologie Examination 71
Linda L. Blythe and Harold N. Engel
Components of the equine nervous system are described includ-
ing classical anatomy and newer sensory innervation maps that
are useful for localizing lesions to and within the nervous system.
The key components in a neurological examination that help
differentiate primary neurologie disease from musculoskeletal
disorders are explained. Gait deficits associated with neurologie
dysfunction are listed as well as diagnostic aids and an overview
of differential diagnoses.

Spinal Muscle Pathology 87
Stephanie J. Valberg
Clinical signs that are easily referred to spinal muscle pathology
include atrophy of epaxial muscles, focal swelling and palpable
tenderness, as well as enlarged muscles with increased tone. Less
easily recognized signs include rigidity of the spine, shortened
stride, hindlimb lameness, and indicators of poor performance.
Muscle biopsy is one option in evaluating sore backs and is best
used when physical examination and imaging procedures do not
reveal a likely diagnosis or when conventional treatments are
unsuccessful. Rhabdomyolysis of spinal muscles may be due to

nutritional myodegeneration (foals), récurrent exertional rhabdo-
myolysis, and polysaccharide storage myopathy. Atrophy of spi-
nal muscles can be due to severe rhabdomyolysis, immune-re-
lated myopathy, or neurogenic atrophy from nerve trauma, EPM,
or EMND.

Spinal Ligament Pathology 97
Carol Gillis
Young elite athletes, particularly horses used for jumping, are at
a relatively high risk for injury to the ligaments associated with
the axial skeleton. Extreme back flexion appears to be a contribut-
ing factor to ligament damage. Back pain due to injury of the
ligaments of the axial skeleton has often been considered to be
secondary to lower limb injury, to the extent that a separate ,
definitive diagnosis, treatment, and prognosis were unnecessary.
Diagnostic imaging, ultrasound in particular, has demonstrated
ligamentous damage that can be the limiting factor in return to
previous athletic use. A high index of suspicion for back ligament
damage during clinical examination for hind limb lameness will
lead to improved diagnosis and therapy.

Osseous Spinal Pathology 103
Kevin K. Haussier
Pathologic changes have been observed at the spinous processes,
intervertebral articulations, and sacroiliac joints in horses. Varying
severity of degenerative articular changes are found in many
articular processes, intertransverse, lumbosacral, and sacroiliac
joints. Pathologic lesions tend to affect multiple vertebral loca-
tions within a specimen. Further studies need to be conducted to
evaluate the clinical significance of the numerous vertebral and
pelvic pathologic findings found in a sample of Thoroughbred
racehorses that died because of unrelated injuries. Increased
knowledge of osseous pathology inherent in equine athletes will
enhance our understanding of the etiopathogenesis of spinal dis-
orders and back pain in horses.

Radiology and Scintigraphy 113
Martin P. Weaver, Leo B. Jeffcott, and Michael Nowak
Radiology and, more recently, scintigraphy are important ancil-
lary diagnostic aids in the diagnosis of a horse with suspected
back pain. Although the image quality is restricted by the size of
the patient, radiographs have been used for several decades. With
the introduction of modern fast-screen film systems, the quality
of the images has greatly improved. These imaging techniques
allow assessment of the anatomy and physiology of structures in
the spine that are difficult or impossible to palpate. This article
reviews the techniques and limitations of imaging the equine

back, in addition to correlating imaging results and clinical find-
ings.

Ultrasonographic Evaluation of Back Lesions 131
Jean-Marie D. Denoix
With récent improvements in ultrasonographic equipment, evalu-
ation of a number of axial skeletal structures is now possible.
Ultrasonography is presently the best technique available for
evaluation of the supraspinal ligament and lumbosacral interver-
tebral discs. It is a useful adjunct to radiology for assessment of
spinous processes and articular processes injuries.

Thermographie Diagnostics in Equine Back Pain 161
Dietrich Graf von Schweinitz
Infrared thermographie imaging (ITI) is the most sensitive objec-
tive imaging currently available for the detection of back disease
in horses. It is, however, only a physiological study primarily of
vasomotor tone overlying other superficial tissue factors. Interpre-
tation requires extreme care in imaging protocol and in under-
standing the significance of altered sympathetic nervous tone and
the sympathetic distribution. Most discussions on back pain have
centered on nociception and inflammatory events. ITI provides
information and localization far more significant than diagnosing
areas of hot spots. Chronic back pain usually involves vasocon-
striction at the affected sites and from ITI studies in man, we
have an opportunity to appreciate chronic pain phenomena that
involves non-inflammatory events. These occur commonly in
horses, but are still seldom recognized and treated.

Medical Management of Back Pain 179
Daniel Marks
The most common causes of back pain and their medical treat-
ment are discussed. These include: dermatologie problems and
conditions resulting from saddle trauma; discomfort and stiffness
owing to injured paraspinal muscles; pain associated with supra-
spinous ligament damage; osseous pain and nerve dysfunction
related to the spine and sacroiliac area; and neurologie diseases
that can manifest as back pain. Bitting problems, cervical pain,
and coexisting lameness are also considered.

Chiropractie Evaluation and Management 195
Kevin K. Haussier
A thorough knowledge of equine vertebral anatomy, biomecha-
nics and pathology is required to understand the principles and
theories behind chiropractie evaluation, and to apply its tech-

niques properly. Chiropractie provides additional diagnostic and
therapeutic means that may help equine practitioners to identify
and treat back problems. Specialized training in the evaluation
and treatment of vertebral joint dysfunction and neuromuscu-
loskeletal disorders place chiropractie in the forefront of conserva-
tive treatment of spinal-related disorders. However, limited re-
search is currently available on equine chiropractie in veterinary
medicine. The future of equine chiropractie is dependent on for-
mal research into the clinical effects of chiropractie techniques and
the basic pathophysiology of spinal-related disorders in horses.

Acupuncture as a Treatment Modality for Back Problems 211
Kerry Ridgway
Concepts of acupuncture in traditional Chinese medicine are pre-
sented for clarity and contrast to Western medical concepts. Vari-
ous acupuncture techniques and methods are discussed including
dry needling, electroacupuncture, acupuncture using hypodermic
needles, and injecting various solutions into the acupuncture
sites. Potential complications and precautions are also presented.
A type of chronic back pain is discussed that is possibly associ-
ated with a radiculopathically induced, hypersensitivity myofas-
cial syndrome that presents as a fibromyalgia-like syndrome.
Effective acupuncture treatment for the described chronic fibro-
myalgia-like syndrome is discussed.

Physical Therapy for the Equine Back 223
Mary W. Bromiley
The principles of physical therapy for the human athlete can be
transposed to the equine. This article suggests the therapeutic
devices that have proved to be pertinent to the equine patient
with back problems. This article also addresses the rehabilitation
stage of physical therapy necessary in order to re-establish eco-
nomic, efficient movement patterns.

Tack and Saddle Fit 247
Joyce Harman
Examining the fit of the saddle is perhaps the most important
aspect of examining a horse with a suspected back problem. If
the back problem is corrected and a poorly fitting saddle is
placed on the back, the problems will return. An ill-fitting saddle
contributes to direct and compensatory lower leg lameness mak-
ing it even more imperative to correct the fit. A correctly fitting
saddle enhances both the horse and rider's ability to perform
with accuracy, lightness, and freedom of movement.

Equine Back Rehabilitation 263
Kerry Ridgway and Joyce Harman
This article introduces the importance of considering all related
physical findings, evaluating the whole horse and determining
the root cause in order to achieve the best treatment results,
prevent recurrence, and return the patient to full function. The
roles of shoeing, turnout, teeth, training aids and devices, com-
pensatory lameness, working surface (footing), longeing, pony-
ing, hot walkers, and swimming are discussed in relationship to
back dysfunction and rehabilitation. Postural analysis and meas-
ures for muscle and postural corrections are also presented.
Ground and under saddle rehabilitative exercises are explained
as to value, concept, and methodology. Rehabilitative modalities
including stretching, massage, magnetic therapy, heat, and cold
are explored as adjunctive therapy.

Index 281


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