80
46TH
ANNUAL
CONGRESS
OF
THE
SAEVA
SKUKUZA
16-‐20
FEBRUARY
2014
Imaging the Tarsus and Proximal
Suspensory
Sarah Puchalski, DVM, DACVR, [email protected]
Diagnostic Imaging of the Tarsus and Proximal Suspensory
In our hospital tarsal radiographs are the second most frequent study, just behind
distal extremity imaging. Radiographs of this region are made for a variety of
reasons ranging from owner request, to positive flexion tests to lameness localised
to this region through diagnostic anaesthesia. For this reason, it is critically
important to relate diagnostic imaging findings with the clinical examination findings
and the patient’s history.
The tarsus and proximal metatarsus are very complicated anatomic regions.
Osseous, articular, synovial and soft tissue structures in the region can all play a role
in the generation of tarsal or proximal metatarsal pain. In no other location is it
more important to possess knowledge of the anatomy and potential pathology.
While relatively routine abnormalities have been described for this region1,2, it is also
important to entertain the concept that unusual or ‘not-yet-described’ lesions can
exist and cause clinically important lameness.
Diagnostic Imaging – Radiology
The importance of the production of high quality radiographs of the tarsus cannot be
overstated. Suboptimal radiographic quality will compromise the clinical utility of the
examination and can result in both false negative and false positive findings. It is also
crit ically important that the radiographic examination include an adequate number of
views to fully assess the region. The number of views will vary with the clinical
presentation, signalment and purpose of the radiographic examination.
At UC Davis, a routine radiographic study includes 5 projections:
1. Dorsal – plantar
2. Dorsal 10° proximal to plantar distal - this allows for a more complete evaluation
of the intertarsal and tarsometatarsal joint spaces.
3. Dorsal 45° lateral 5° proximal to plantar medial distal oblique
4. Lateral – medial
5. Plantar 45° lateral 5° distal to dorsal medial proximal oblique
Each of the radiographic views serves a diagnostic purpose, with one emphasising a
region that another does not. Using all views, in concert, is appropriate for a
thorough evaluation.
Diagnostic Imaging – Ultrasound
Diagnostic ultrasound is a valuable imaging technique that is of great utility for the
evaluation of the regional soft tissues and the proximal metatarsal region (proximal
suspensory ligament)1-4. Ultrasound is also useful for the determination and
characterisation of septic synovial structures such as the bursae, joints or tarsal
sheath5,6. Ultrasound provides a thorough and high quality evaluation of the
peripherally located soft tissue structures such as the collateral ligaments and the
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