The Veterinary clinics of North America. Equine practice.
Publisher:
W.B. Saunders,
Frequency: Three no. a year
Country: United States
Language: English
Start Year:1985 -
ISSN:
0749-0739 (Print)
1558-4224 (Electronic)
0749-0739 (Linking)
1558-4224 (Electronic)
0749-0739 (Linking)
Impact Factor
1.1
2022
| NLM ID: | 8511904 |
| (DNLM): | SR0053812(s) |
| (OCoLC): | 11078671 |
| LCCN: | sn 84006968 |
| Classification: | W1 VE929F |
Local anesthetics as pain therapy in horses. This article describes the rationale behind the use of systemically administered lidocaine as an analgesic. The analgesic efficacy of intravenously administered lidocaine is well documented by studies in human patients and laboratory animals. The mechanism by which systemically administered lidocaine produces analgesia is uncertain but is thought to include action at sodium, calcium, and potassium channels and the N-methyl-D-aspartate acid receptor. In addition, the anti-inflammatory actions of lidocaine are important in producing analgesia because inflammatory mediators augment neuronal excit...
Laminitic pain: parallels with pain states in humans and other species. Laminitis poses a threat to all horses, and is widely considered as being one of the most important diseases of horses and a global equine welfare problem. The effects of laminitis lead to debilitation, development of pronounced digital pain, and great suffering in the afflicted animal. The precise pathophysiological processes that result in laminitic pain are poorly defined, and hence the delivery of effective palliative care is clinically challenging. Knowledge and understanding of pain states in other animal species may further aid the elucidation of equine laminitic pain mechanisms, guide ...
Pain: mechanisms and management in horses. Pain is a multidimensional sensory phenomenon that has evolved as a protective method for maintaining homeostasis and facilitating tissue repair. Both excitatory and inhibitory physiologic and pathologic mechanisms are involved in its generation and maintenance. Untreated pain and nervous system changes (plasticity) that occur during chronic pain make pain much more difficult or impossible to effectively treat. Therapies directed toward the treatment of pain should be mechanism based and preventative whenever possible. Prospective, randomized clinical trials conducted in horses that suffer fro...
Spinal anesthetics and analgesics in the horse. In the past 10 years, there have been many recent advances in spinal techniques in horses, both epidural and subarachnoid, to identify drugs or drug combinations that have sensory effects without motor nerve paralysis, thus providing pain control without these horses becoming recumbent. Opioids, alpha-2 agonists, dissociative drugs, and others have been investigated. Many of these drugs, which have serious side effects when injected systemically in horses, have been shown to have useful analgesic effects when injected spinally. Morphine-like opioids have the greatest potential for spinal use a...
Pain in osteoarthritis. This article focuses on pain associated with osteoarthritis (OA). It first describes the basic biology of articular cartilage and other joint structures and the defining features of the osteoarthritic disease process. Subsequently, the possible origins of pain in OA are discussed before embarking on how to manage this clinical entity. The emphasis is on the pharmacologic management of joint pain, and attention is paid to systemic therapeutic strategies as well as to local (intra-articular) treatment modalities. Nonmedical ways of modulating joint pain are briefly mentioned, but not extensively...
Alpha-2 agonists as pain therapy in horses. Alpha-2 agonists, such as xylazine, clonidine, romifidine, detomidine, medetomidine, and dexmedetomidine, are potent analgesic drugs that also induce physiologic and behavioral changes, such as hypertension, bradycardia, atrioventricular block, excessive sedation and ataxia, all of which can potentially limit their systemic use as analgesics in some clinical cases. The use of medetomidine and dexmetomidine has been introduced for equine anesthesia/analgesia, and although not approved in this species, their increased specificity for alpha-2 receptors may offer some potential advantages over the...
The role of manual therapies in equine pain management. Manual therapy includes a diverse array of techniques, such as touch therapies, massage, physical therapy, osteopathy, and chiropractic, that were originally developed for use in humans and have been gradually applied to horses. All forms of manual therapy have variable reported levels of effectiveness for treating musculoskeletal issues in humans, but mostly only anecdotal evidence exists in horses. This article explores the scientific literature for evidence of efficacy, safety, and common mechanisms of action of the different forms of manual therapies for potential use in managing acute or ...
Clinical presentation, diagnosis, and prognosis of chronic laminitis in Europe. The terminology relating to laminitis is confusing. This article describes how equine veterinarians, by using their eyes and fingers alone, can diagnose and evaluate a case of chronic laminitis. This evaluation will enable veterinarians to give a statistically significant prognosis that can be further refined by measurements taken from plain, weight-bearing lateromedial radiographs of the affected hooves. Should invasive techniques such as digital venography also be used, the results of both techniques are complementary.
Supporting limb laminitis. Supporting limb laminitis poses a threat to all horses suffering from severe unilateral lameness. Despite its devastating effects, relatively little is known about the precise pathologic processes that lead to its development. This article reviews the potential mechanisms of supporting limb laminitis, and the authors present some preliminary data based on advanced imaging and computer-based modeling techniques aimed at further elucidating the etiology of this unique form of laminitis. Gaining a better understanding of the pathologic processes that lead to supporting limb laminitis is essential...
Maggot debridement therapy for laminitis. Maggot debridement therapy is a nontraumatic, minimally invasive method to treat infections in a foot compromised by chronic laminitis. A mechanical strategy must first be in place to address the instability of the distal phalanx and hoof capsule. Adverse reactions to maggot debridement therapy are uncommon and the only side effect observed has been irritation or hypersensitivity at the site. Chronic laminitic cases of sepsis/necrosis within the hoof benefit from this procedure due to the noninvasive, continuous debridement and healing properties provided by the larvae.
Field treatment and management of endocrinopathic laminitis in horses and ponies. Endocrinopathic laminitis in horses and ponies has the potential to cause extensive damage to the feet before clinical signs of laminitis are apparent. Early diagnosis and intervention based on the detection and control of hyperinsulinemia are critical if the crippling changes that are seen in the disease are to be avoided. Preventing endocrinopathic laminitis, rather than treating it, is good practice management benefiting not only equine patients but also their owners.
Pasture management to minimize the risk of equine laminitis. The sugar, starch, and fructan content (collectively referred to as nonstructural carbohydrates [NSC]) of pasture plants is dependent on the environmental conditions under which they have grown. Pasture that is stressed by cold, drought, or lack of nutrients can be 2 to 3 times higher in NSC than pasture that grows quickly in warm weather and is adequately watered and fertilized. Horses at risk for laminitis should have access to pasture limited or be removed completely when environmental conditions are conducive to high levels of NSC accumulation.
Supporting limb laminitis. Supporting limb laminitis poses a threat to all horses suffering from severe unilateral lameness. Despite its devastating effects, relatively little is known about the precise pathologic processes that lead to its development. This article reviews the potential mechanisms of supporting limb laminitis, and the authors present some preliminary data based on advanced imaging and computer-based modeling techniques aimed at further elucidating the etiology of this unique form of laminitis. Gaining a better understanding of the pathologic processes that lead to supporting limb laminitis is essential...
Farriery for chronic laminitis. Laminitis is considered chronic once the distal phalanx has displaced within the hoof capsule. Chronic laminitis generally occurs as a direct sequel to acute laminitis. Clinical evaluation of chronic laminitis is best performed with a thorough clinical examination and radiography. The mainstay of hoof care is therapeutic farriery. In this article, the goals and principles of hoof care, the appropriate trim and various shoes that form the bulk of farriery for chronic laminitis, and surgical treatments are discussed.
Current concepts on the pathophysiology of pasture-associated laminitis. Epidemiologic studies indicate that most laminitis cases occur in horses and ponies kept at pasture, hence the term 'pasture-associated laminitis'. Clinical cases of laminitis most often occur under conditions that favor accumulation of rapidly fermentable nonstructural carbohydrates (fructans, simple sugars, or starches) in pasture, and animals with an equine metabolic syndrome (EMS) phenotype (insulin resistance, abnormal insulin dynamics, +/- obesity) seem to be at highest risk for developing the condition. Although the mechanisms linking consumption of pasture forage with development of la...
Digital venography in horses and its clinical application in Europe. Clinical diagnostic venography allows in vivo visualization of the digital venous system and the effects of venocompression related to foot load and laminitis pathology. Venography has predictive potential and helps the clinician anticipate and treat laminitis tissue damage before it is detectable by plain radiography. The authors describe the podiatry radiographic technique to correctly perform digital venography and the modifications they have developed. The authors provide guidelines for the interpretation of laminitis venograms in the context of laminitis chronology. Frequent venographic m...
Chronic laminitis: foot management. Laminitis is a disease of the suspensory apparatus of the distal phalanx, which can advance to the chronic stage with varying degrees of structural failure. Because the disease may ultimately lead to mechanical failure of the digit, a foot management plan is required to effectively and mechanically treat these cases. Many laminitis cases can be successfully rehabilitated back to athletic soundness, light use, breeding, or pasture soundness, whereas others suffer from permanent instability and never enjoy an acceptable level of comfort. To understand how to minimize damage in the acute laminiti...
First aid for the laminitic foot: therapeutic and mechanical support. The goals of mechanical treatment during the acute phase of laminitis are to preserve the lamellar interface by reducing the forces that are compromising its integrity and to make the horse more comfortable. Early decision making is important in managing acute laminitis. This article helps the practitioner to identify some of the commonly used and accepted methods of protecting the laminitic foot. The materials available and the theories behind their use are also described. The laminitic foot needs to be understood before determining methods for its support. Most treatment options involve shif...
Endocrinopathic laminitis. In laminitis occurring in the field, as opposed to laminitis occurring during hospitalization or severe illness, endocrinopathic laminitis is the predominant form of laminitis. Prevalent causes of endocrinopathic laminitis are ECS and EMS. Exclusion of inflammatory or weight bearing causes of laminitis and focussing on the identification and treatment of underlying endocrine conditions will improve laminitis management strategies.
Neuropathic pain management in chronic laminitis. Managing pain in horses afflicted by chronic laminitis is one of the greatest challenges in equine clinical practice because it is the dreadful suffering of the animals that most often forces the veterinarian to end the battle with this disease. The purpose of this review is to summarize our current understanding of the complex mechanisms involved in generating and amplifying pain in animals with laminitis and, based on this information, to propose a modified approach to pain therapy. Furthermore, a recently developed pain scoring technique is presented that may help better quantify pain and t...
Endocrinopathic laminitis: reducing the risk through diet and exercise. Certain individual animals appear predisposed to recurrent pasture-associated laminitis, but the exact mechanisms underlying their predisposition remain a fundamental question in laminitis research. The risk of endocrinopathic laminitis can be reduced if steps are taken to improve insulin sensitivity and reduce inflammation using strategies based on exercise and diet. Exercise has been shown to reduce insulin resistance and suppress inflammation, and dietary manipulation can significantly affect insulin sensitivity.
Laminitis and the equine metabolic syndrome. Although much has been written about laminitis in the context of its association with inflammatory processes, recognition is growing that most cases of laminitis examined by veterinarians in private practice are those associated with pasture grazing, obesity, and insulin resistance (IR). The term 'endocrinopathic laminitis' has been adopted to classify the instances of laminitis in which the origin seems to be more strongly associated with an underlying endocrinopathy, such as either IR or the influence of corticosteroids. Results of a recent study suggest that obesity and IR represent the mos...
The pharmacologic basis for the treatment of endocrinopathic laminitis. Although the treatment and management of laminitis in the horse requires a holistic and often multidisciplinary approach from the veterinarian, farrier, and nutritionist, this review focuses on pharmacologic interventions that might have prophylactic benefit, specifically in the horse with laminitis as a result of pituitary pars intermedia dysfunction and equine metabolic syndrome.
Corticosteroid-associated laminitis. A direct causal association between corticosteroid use and laminitis has yet to be proven scientifically, and there have been few studies specifically addressing this aspect. New evidence, however, is improving the understanding of the causes of laminitis, particularly related to endocrine factors. The focus of this article is discussing the circumstances under which steroids might cause this condition.
Hyperinsulinemic laminitis. Laminitis occurring in association with hyperinsulinemia is frequently encountered in today's equine population. New evidence suggests that hyperinsulinemia is the direct cause of this form of laminitis, rather than insulin resistance per se. The mechanism by which elevated serum insulin concentrations result in lamellar dysfunction is currently under investigation by many researchers and the use of a new insulin infusion model for investigating the pathogenesis of insulin-associated laminitis will doubtless enhance progress in this field of research. By focusing on the metabolic and vascular ...
Acute laminitis: medical and supportive therapy. Acute laminitis is a serious complication of many primary conditions in the horse. This article summarizes the most appropriate approach to management of the horse with acute laminitis, based on current information.
Chronic laminitis: strategic hoof wall resection. In the chronic-laminitic foot, severe soft-tissue compression and compromised circulation can result in osteitis and sepsis at the margin of the distal phalanx. Resultant inflammation and sepsis may cause the coronary corium to swell, drain, or separate from the hoof capsule, usually within 8 weeks of laminitis onset. Slow-onset cases of soft-tissue impingement can develop secondary to distal phalanx displacement due to lack of wall attachment. With either presentation, partial upper wall resection is required to reverse compression and vascular impingement by the hoof capsule. If the patholog...
Pathology of the distal phalanx in equine laminitis: more than just skin deep. The etiopathogenesis of laminitis is complex and involves multiple tissue types. It may be initiated by biomechanical, traumatic, inflammatory, vascular, toxic, and metabolic factors. Although histopathologic changes occurring within the lamellae of experimental models of laminitis are well described and reported, histopathologic changes occurring in the distal phalanx are not, even though gross and radiographic evidence of disease are often apparent and bony lesions could be considered a significant source of pain. Recent scientific evidence indicates that the microenvironment of bone is an i...