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Equine dermatological cases can be investigated and managed using a logical diagnostic approach. In the first instance, a carefully taken history, together with a physical and dermatological inspection, form the backbone of investigations. Once an initial history has been taken, the clinician can allocate a skin case to one of seven different groups of clinical presentation: pruritus, alopecia, nodules, crusting and scaling, pigmentary abnormalities, ulcerations and erosions, or pedal or pastern dermatitis. This in turn allows the clinician to formulate a list of differential diagnoses based on the presenting signs and to undertake specific diagnostic tests. This article describes in detail these initial techniques and advises which should be employed for each clinical presentation, together with more advanced investigations where necessary.

DIAGNOSTIC ultrasonography for the musculoskeletal system in the horse was first used in the early 1980s. Initial applications were directed towards the diagnosis of flexor tendon and ligament injuries in the distal limb, but this modality is now commonly indicated for the assessment of the stifle, hock, fetlock, carpus, pastern and coffin joints. This article describes the use of diagnostic ultrasound in horses to examine these joints, as well as muscle and bone, outlining normal versus pathological findings in each case. While this imaging technique may also be employed to examine the shoulder, hip, cervical facet and temporomandibular joints, the indications are less frequent and, hence, are not discussed in this article. In all cases, knowledge of the normal anatomy is essential in obtaining diagnostically useful images and aiding interpretation.

THE foot and pastern of the horse must be the most frequently implicated region in terms of lameness. Recent years have seen an increase in the use of, and some confusion in the interpretation of, diagnostic (intra-articular and perineural) analgesia in this region. With this in mind, and the fact that improved ultrasonographic facilities and sporadic availability of magnetic resonance imaging have not reduced the demand for high quality diagnostic radiographs of the foot and phalanges, it is important that veterinary surgeons in equine practice keep abreast of developments in radiographic techniques. This article discusses ways of enhancing radiography of this region and provides examples of radiological conditions frequently seen in practice.

WHEN preparing for radiographic examination of a horse, the projections required, positioning of the animal and centring of the primary x-ray beam are routinely considered, whereas other aspects of the procedure, such as choice of screens and films, and processing techniques, can easily be overlooked. The ideal would be to select the best of each of the many factors that affect the quality of a radiograph when establishing a radiographic technique. Ultimately, however, the final choice is a compromise, as selecting the best option for one factor often has a negative effect on another. In deciding how to obtain the best images possible, the whole procedure, from positioning of the horse to darkroom technique, needs to be considered. This article provides guidance on some key aspects and draws attention to the requirements of current radiation safety regulations. Future articles will discuss radiography of specific anatomical regions of the horse, commencing in the next issue with the foot and pastern.

IN the previous article, the principles of local analgesic techniques were discussed in general terms (In Practice, February 1997, pp 82-88). This article describes specific nerve block techniques and their potential limitations. Although, theoretically, nerve blocks should start as far distally as possible - eliminating, sequentially, pain arising from the plantar aspect of the foot, the foot and pastern, and then fetlock - the incidence of distal limb problems is less common in hindlimbs than in forelimbs. Therefore, a strategic approach is suggested based upon the results of a detailed clinical examination, gait analysis and response to flexion tests.

WE read with interest the article ‘Current concepts of navicular syndrome: diagnosis and treatment’, by Richard Coomer, Holly Thomas and Shaun McKane in In Practice (June 2013, vol 35, pp 325-335). While the article provides a good basic overview of the complex topic of navicular syndrome and helps to simplify some of the recent advances that have been made in our understanding of the condition, it also appears to contain some misleading and unsubstantiated opinions that we feel obliged to comment on. The following statement is of greatest concern: ‘Egg bar shoes are contraindicated for navicular syndrome and we no longer use them because they provide no frog and minimal heel support. They do not reduce the force exerted by the DDFT on the navicular bone and can also negatively affect stride quality (Willemen and others 1999). When used in clinical cases, we have found that eventually the whole sole can collapse through the central hole in the shoe, creating or exacerbating the broken back hoof pastern axis and increasing tension on the navicular apparatus.’ Although it is true that Willemen and colleagues found that egg bar shoes did not reduce the force exerted by the DDFT on the navicular bone and seemed to reduce …