The use of chiropractic manipulation in horses is a growing trend in spite the paucity of scientifically tested clinical data in horses to support its use. Much of the principles of equine chiropractic stem from the human practice but it should be noted that there are many difficulties when comparing the use of chiropractic in humans and equines. In human chiropractic:

• Diagnosis is based on specific first hand complaints by the patient.
• Radiography used to document lesions, guide manipulation, and rule out problems that should not have chiropractic manipulation.
• Manipulative procedure techniques based on hundreds of years of experience.

None of these key elements are present in equine chiropractic and so these human clinical studies in no way support or refute the usefulness of the practice. Besides the lack of scientific support there are physical concerns. The very long dorsal and lateral spinous processes and the thick associated epaxial musculature the equine spinal cord is sheathed in many inches of muscle from the 1st cervical vertebrae all the way to the caudal vertebrae. This makes direct observation, palpation, and potentially adjustment more difficult in the equine patient.

In spite of this, the practice continues to grow due to the many anecdotal reports of clinical improvement following manipulation. As with all anecdotal evidence many questions remain but most of all:

• What would have happened if no treatment were applied?
• What if some other treatment were used?
• If this is useful treatment what are clear indications and contraindications for manipulation?

Science is replete with examples that illustrate how anecdotal reporting of cause and effect can be wrong. Experience teaches us that it is science's strength that it is able to determine, within a statistical error, cause and effect in complicated biological systems. The lack of scientific support, at least in refereed scientific and veterinary journals, for what equine chiropractors are doing is a warning.

This article discusses principles of vertebral joint dysfunction, chiropractic theory, and manipulation techniques from the view of the chiropractor. This article represents a alternative view and helps educate about the potential indications and use of chiropractic. It also contains scientific report summaries on the current status of chiropractic manipulation. It should not be looked as a endorsement for its use but should help you decide if this is a treatment modality you wish to try.

Most of this article has been excerpted and edited from a presentation given to the American Association of Practitioner in 2000 by a well known veterinarian and chiropractor Kevin K. Haussler, DVM, DC, PhD (Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853-6401). This is his view on equine chiropractic though I have rearranged the order of presentation and tried to lighten the medical terminology a bit. You should keep your dictionary handy however. In his summary he concludes:

"A thorough knowledge of equine vertebral column anatomy, biomechanics, and pathology is required to understand the principles and theories behind chiropractic and to apply its techniques properly. Chiropractic provides additional diagnostic and therapeutic means that may help equine practitioners to identify and treat the primary cause of lameness or poor performance. Chiropractic provides specialized evaluation and treatment of joint dysfunction and conservative treatment of neuromusculoskeletal disorders that are currently lacking in traditional veterinary medicine. However, limited research is currently available on equine chiropractic and other nontraditional modalities in veterinary medicine. In 1996, the AVMA's Committee on Alternative and Complementary Therapies suggested that the research community should be encouraged to prioritize avenues of research and to allocate research funds to projects that will provide further scientific evaluation of these modalities. The use of chiropractic principles and techniques on animals is dependent on future research into the clinical effectiveness and indications for management of back problems in horses."

Objective data about the effects of chiropractic manipulation is beginning to be developed and presented below. But the questions Dr. Haussler poses still remain unanswered so chiropractic remains an alternative therapy waiting scientific support.

Also addressed below are some of the oddities about chiropractic terminology which has led to much misunderstanding about the nature of chiropractic diagnosis and adjustment. For instance in chiropractic terms a subluxation is not a subluxated joint but instead a "vertebral segment dysfunction" (VSD) and is defined below. Adjustment does not correct a medical subluxation but the vertebral segment dysfunction.