Beating Muscle Injuries for Horses, Jack Meagher, Hamilton Horse Associates 1985

The author of this guide has been a human sports mas- seur therapist for many years, and is currently a technical advisor for sportsmassage to the American Massage Thera- py Association. His experience has resulted in his develop- ment of "Muscular Therapy", a concept he routinely applies to dogs, humans and horses.

Muscular Therapy (MT) is described by Meagher as "pre- r 'f ventive the apy, in contrast to typical "Physical Therapy",

which he considers nothing more than the application of physical rehabilitation techniques to sports-related injuries. According to Meagher, MT has been consciously designed to help an athlete fulfill 3 goals: "To be as good as possible; to be as safe as possible; to last as long as possi- ble." A fundamental tenet of MT is that most soft tissue injuries in horses result from straining tightened and stressed muscles: "The physiological response of muscle to trauma of any type is first tightening...foliowed by the development of a spasm at the exact spot where the trauma occurred."

Most of this volume consists of excellent descriptions and "how to" illustrations for applying MT to specific equine muscular complaints. Lessons begin with "Using Your Hands", a guide to the development of the proper "tools". The treat~pent of 25 specific "stress points" is then clearly illustrated and described in detail, along with the behavioral cues suggesting each type of soreness. The reader will fred that many of the technical details of the MT method are similar to those of the "T.E.A.M." methods of Linda Tellington-Jones of Alberta. However, in marked con- trast to the philosophy of TelIington-Jones, Meagher has successfully demystified his methodology and makes no metaphysical claims.

Many horsemen, veterinarians and trainers may already be practicing "common sense" versions of preventive or thera- peutic massage. Such attempts will be strengthened and their effectiveness will be increased by the adoption of the rational MT method. Those who haven't experimented with such techniques should be encouraged to attempt the MT method. In the words of the author, "You have the option of preventing many of the problems that develop." This useful guide will make it easier to exercise that option. MJG

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Chemical Neurolysis in the Equine, Martin I. Levman, Simcoe Hall Publishing Co., 1985

In his preface, author Levman states "There is very little scientific literature on chemical neurolysis in the veterinary sources...The purpose of this manual is to give the veter- inarian the necessary background in order for him or her to excell...clinical success depends greatly on how thorough an understanding one has of every aspect of the therapy."

Levman has in fact provided such a foundation. Relying on a minimal background in the neurologic sciences, in the f '~t half of this book he has supplied a very readable and coherent review of the neurophysiology, neuroanatomy and neuropathology relevant to a basic understanding of the physiology of pain in horses. He has drawn an important distinction between the quality and quantity of pain, and argued convincingly that the nature of perceived pain is highly dependent on the pathways it travels between peripheral nociceptors and central nervous system "aware- ness". It is this ability to "sort" pain by source and path- way that allows the effective application of selective neurolysis.

The cellular mechanisms involved in the actions of neurolytic agents are clearly summarized. According to Levman, "The 'perfect' neurolytic agent is one which selec- tively destroys peripheral pain transmitting fibers" (the small unmyelinated type C pain fibers), while sparing motor innervation. Levman's practice of chemical neuro- lysis relies on the selective properties of several neurotoxic compounds to damage only these type C fibers when admin- istered in appropriate doses. Among these compounds are ammonium chloride and sulfate salts, absolute ethanol, phenol (carbolic acid) and chlorocresol.

The second half of this manual consists of practical instructions for practicing chemical neurolysis on equine patients. Well-illustrated anatomic guides are abundant. Separate dosage and administration schedules have been included for use on those animals being treated over 72 hours before their next competition, and for those to be treated within 72 hours of a performance event.

Levman recognizes the controversial nature of the thera- peutic approach he advocates. "(Veterinary neurolysis) has never enjoyed the same respectability as seen in its human counterpart." However, Levman views the permanent de- struction of nerves as merely an extreme form of local anes- thesia: "all forms of neurolysis play a very important role in clinical veterinary medicine."

In a clinical sense there can be little argument with Levman's claims. His response to criticisms questioning the ethics of neurolytic therapies is quite defensible: "One must use whatever is available to prevent the animal from going to slaughter...The techniques of chemical neurolysis when used judiciously can result in maintaining the special rapport between the two species." He may exceed his credi- bility when he declares that "neurolysis has the capability of generating outstanding changes in the patient", parti- cularly when an increase in athletic performance is clearly implied. Pain is in fact nature's way of telling the horse

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something is wrong; encouraging more serious injury through the masking of pain is always a questionable practice which should only be undertaken after considerable soul-searching.

Perhaps even more disappointing is the nature of the appeal for support among veterinarians for the practi~e of chemical neurolysis: "it is a technique which is almost guaranteed to remain completely the property of a veter- inarian and only a veterinarian...The horseman himself tends to be out and out frightened of even attempting the technique, thereby ensuring chemical neurolysis as a veter- inary monopoly." It is dismaying that such a blatant attempt to motivate by greed must discolor an otherwise instructive guide to a potentially useful therapeutic practice. (MJG)

Equine Ergogenics, Martin I. Levman Simcoe Hall Publishing Company 1986

The title of this book is taken from the greek "ergo" meaning work and "gennan" meaning to produce. "Ergo- genics" is defined as the scientific study of increasing work output. As practiced by Levman, it is taken to mean "artificially increasing an athlete's capacity to work." This book is intended by the author to be a revision of "Veter- inary Race and Performance Preparation", a guide to the pre- race alteration of a racehorse's fitness. This update has been necessitated, according to its author, in part because "A great many products can no longer be used because the testing laboratories have learned to detect them." However, the continued development of artificial performance en- hancers is desirable because "an uneconomical horse in the world of competitive equine sport is an animal on its way to destruction."

Virtually every ergogenic aid available is discussed and evaluated. B-vitamins, tyrosine, arsenic and strychnine are considered to be effective stimulants of even healthy condi- tioned horses. Thiamin (vitamin B-l) is also treated as a "motion tranquilizer", effective in calming horses that be- come excitable when performing. Tryptophan, by virtue of its conversion to serotonin within the central nervous sys- tem, is cited as a potential tranquilizer ("sleep inducer") for the nervous horse between competitions. Tyrosine, in amounts 5 to 6 times those given when used as a stimu- lant, is identified as another quieting agent.

Analgesic compounds recommended include the cortico- steroids, ACTH, D-leucine and D-phenylalanine. Interest- ingly, etorphine use is strongly criticized; it is difficult to determine whether its negative reception results from its extreme narcotic danger or its illegality and the potential for DEA prosecution ("these heavy-duty boys carry guns").

The issue of the therapeutic management of exercise- induced pulmonary hemorrhage is covered in some detail. The pharmacology of clotting inducers (vitamin K, calcium and hesperidin ), estrogens, furosemide, camphor and iodides is discussed in relation to their effects on ventilatory func- tion and "bleeding".

The metabolic ergogenic aids advocated by Levman fall

40

into 2 categories: those which are anaerobic in effect and those which increase aerobic capacity. Aerobic aids consi- dered promising (i.e., purported to stimulate the rate of ATP production during aerobic work) include phosphate loading and supplementation with L-carnitine, dimethyl- glycine (DMG; B-15; pangamic acid) and trimethylglycine. Anaerobic aids buffer the lactic acid produced during anaer- obic work, thereby presumably delaying the onset of fatigue. Among those that are described as being effective are sodium bicarbonate, histidine and alanine (via carno- sine). In the author's opinion, claims of the effectiveness of ATP or inosine supplementation or carbohydrate loading are not justified.

The potential ergogenicity of various hormones, growth factors, DMSO, vitamin E, selenium and the glycosamino- glycans is also considered. The effectiveness of these compounds apparently awaits further experimentation.

While the array of potential undetectable (or if detectable, legal) ergogenic substances made available by this guide is vast, the author does temper the reader's enthusiasm with an admonition to practice self-restraint: "1) we cannot give or do anything to an animal which could be dangerous to that animal; 2) we cannot give or do anything to an animal which could be dangerous to humans involved; 3) we cannot give or do anything to a horse which could be dangerous to any other humans or animals involved in a given athletic competition."(MJG)

Limbs of the Equine, LeRoy Amos, Ashberry Acres, 1986

The motivation for the creation of this large-format atlas was the realization that no suitable collection of illustra- tions to aid farrier-client communication was available. Originally begun as a poster, the project quickly grew beyond such a modest presentation.

The atlas consists of beautiful detailed multi-colored three dimensional drawings of the extensor muscles and tendons of the left front and hind limbs, the synovial sheaths and bursae of the distal fore and hind limbs, and the bony and ligam~entous architecture of the knee and hock joints (viewed from 4 directions). Even more impressive are the forelimb and hind limb "flip charts". The bottom layer of each chart displays the skeletal structure of the limb. Successive layers of transparencies illustrate the tendons and musculature of the legs. The complex structures of the hoof are similarly presented in a "flip chart."

All of the illustrations are large, clearly labelled and ex- tremely graphic. Approximately half of the pages of the atlas are taken by brief descriptions of the most common unsoundnesses. The combination of charts and text should prove invaluable during those occasionally confusing decision-making discussions. The only drawback to obtain- ing this atlas is that its appearance and presentation are of such high quality that it will probably remain in the office while additional copies will need to be purchased for the barn. (MfG)

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