Validation of a new radiographic protocol for Asian elephant feet and description of their radiographic anatomy

Abstract

Foot problems are extremely common in elephants and radiography is the only imaging method available but the radiographic anatomy has not been described in detail. The aims of this study were to develop a radiographic protocol for elephant feet using digital radiography, and to describe the normal radiographic anatomy of the Asian elephant front and hind foot. A total of fifteen cadaver foot specimens from captive Asian elephants were radiographed using a range of projections and exposures to determine the best radiographic technique. This was subsequently tested in live elephants in a free-contact setting. The normal radiographic anatomy of the Asian elephant front and hind foot was described with the use of three-dimensional models based on CT reconstructions. The projection angles that were found to be most useful were 65-70° for the front limb and 55-60° in the hind limb. The beam was centred 10-15 cm proximal to the cuticle in the front and 10-15 cm dorsal to the plantar edge of the sole in the hind foot depending on the size of the foot. The protocol developed can be used for larger-scale diagnostic investigations of captive elephant foot disorders, while the normal radiographic anatomy described can improve the diagnostic reliability of elephant feet radiography.

Skeletal pathology and variable anatomy in elephant feet assessed using computed tomography

“…We should not be complacent with lack of lameness or externally apparent signs. A comprehensive evaluation of foot health in elephants should therefore include ‘baseline’ foot radiographs to establish the ‘normal’ anatomy for that individual, and annual assessment thereafter using radiographic protocols with standard views optimal for the detection of pathological lesions (Mumby et al, 2013). In addition, weight management, regular exercise, a clean and appropriate environment (with minimal time spent on hard surfaces; Miller, Hogan & Meehan, 2016), and other measures to prevent over-loading, injury and infection should not be overlooked.…”

“…Lameness is not always an obvious feature in elephants with foot problems (Lewis et al, 2010), and radiography of the distal limb has been described to diagnose and monitor foot problems (e.g., Hittmair & Vielgrader, 2000; Siegal-Willott et al, 2008; Kaulfers et al, 2010; Mumby et al, 2013). Over the recent years advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) have been more commonly used in veterinary practice for musculoskeletal and other problems, but their use for elephants is precluded by body size and transport issues.…”

Peer Review #1 of "Skeletal pathology and variable anatomy in elephant feet assessed using computed tomography (v0.1)"

“…We should not be complacent with lack of lameness or externally apparent signs. A comprehensive evaluation of foot health in elephants should therefore include 'baseline' foot radiographs to establish the 'normal' anatomy for that individual, and annual assessment thereafter using radiographic protocols with standard views optimal for the detection of pathological lesions (Mumby et al, 2013). In addition, weight management, regular exercise, a clean and appropriate environment (with minimal time spent on hard surfaces; Miller et al, 2016), and other measures to prevent over-loading, injury and infection should not be overlooked.…”

“…Lameness is not always an obvious feature in elephants with foot problems (Lewis et al, 2010), and radiography of the distal limb has been described to diagnose and monitor foot problems (e.g. Hittmair and Vielgrader, 2000;Siegal-Willott et al, 2008;Kaulfers et al, 2010;Mumby et al, 2013). Over the recent years advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) have been more commonly used in veterinary practice for musculoskeletal and other problems, but their use for elephants is precluded by body size and transport issues.…”

RADIOGRAPHIC PROTOCOL AND NORMAL ANATOMY OF THE HIND FEET IN THE WHITE RHINOCEROS (CERATOTHERIUM SIMUM)

“…Target training (rhinoceros moves to a target on instruction) is the most commonly employed and is used as a basis for training of other techniques such as chute training, weigh scale training, blood sampling, and foot care. 13,30,31,32 It would be unfeasible with the current training practices to expect the majority of rhinoceroses to lift their feet for positioning as is done for elephant radiography . There is however potential for target‐trained rhinoceroses to be trained to walk onto a cassette tunnel for this protocol to be employed, allowing for accessible and simple radiography of conscious rhinoceroses.…”