46TH
ANNUAL
CONGRESS
OF
THE
SAEVA
SKUKUZA
16-‐20
FEBRUARY
2014
137
Cervical radiology
A. N. Dimock and S. M. Puchalski*
William R. Pritchard Veterinary Medical Teaching Hospital, Large Animal Radiology, University of
California, Davis, USA.
*Author to whom correspondence should be addressed.
Interpretation of equine cervical spine radiographs is difficult. As with all other
anatomic regions, 2 factors are critical to their accurate interpretation. Firstly, the
evaluator must know what they are looking for and secondly, they must know where
to look. The body of literature is continually increasing with respect to the ‘what’ of
clinically important diseases of the cervical spine. Traditionally, the more common
diagnoses made on cervical radiographs include equine ‘Wobblers’ or cervical
stenotic myelopathy, cervical facet joint disease or overt trauma with vertebral body
fracture/luxation (Papageorges et al. 1987; McConnico et al. 1989; Mayhew et al.
1993; Nelson et al. 1994; Hudson and Mayhew 2005; Vos et al. 2008; Down and
Henson 2009). These conditions are in addition to more limited numbers of cases of
unusual diagnoses such as facet fracture as reported by Withers et al. (2009a), facet
hypertrophy and discospondylitis (Adams et al. 1985; Fur r et al. 1991; Ricardi and
Dyson 1993; Giguere and Lavoie 1994; Newton-Clarke et al. 1994; Colbourne et al.
1997). There are few publications available on the production and interpretation of
neck radiographs, particularly oblique radiographs (Whitwell and Dyson 1987; Down
and Henson 2009; Withers et al. 2009b) although numerous indications for
radiography exist. Some indications include neurological deficits, pain and stiffness,
abnormal posture and forelimb lameness. Important diagnostic information is
frequently held hostage in cervical spine radiographs but with the right interpretation
skills can be released by the interpreting clinician.
Cervical radiography is complicated by the complex regional anatomy,
superimposition of symmetric structures and difficulty obtaining orthogonal (ventraldorsal or dorsal-ventral) radiographic views. The case report by Withers et al.
(2009a) describes a case of a cervical articular facet fracture which was difficult to
characterise on the routine lateral-lateral radiographic projections and much more
completely assessed on oblique views. The investigators further improved their
characterisation of the lesion by utilising a novel cineradiographic technique on a Carm fluoroscopy unit. This technique provides multiple projections through 100º of
rotation with the centre of rotation at the abnormal facet, a technique not unlike
linear tomography. The article includes excellent images of the abnormal region,
however, this technology is not available for equine use at many clinics or university
hospitals. The described oblique radiographs performed by the investigators, on the
other hand, are easily utilised by the general veterinary population and can be
essential in the accurate diagnosis of lateralised osseous abnormalities of the spine
such as an articular facet fracture. A review of the methods in obtaining a thorough
radiographic study of the equine cervical spine, including oblique views, with
anatomic correlation is warranted.
Radiographs of the majority of the cervical spine, including oblique views, can be
acquired in the standing horse using the commonly available portable x-ray
generators and detectors (film or digital). Only the caudal cervical spine, C6-C7, C7-
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