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Computed Tomography (CT)

of the Stifle

Ingrid Gielenand Henri van Bree

Introduction

In dogs, the stifle is a frequently injured joint.
Ligamentous and meniscal damage are com-
mon and are associated with secondary degen-
erative changes (Vasseur 1993; Johnsonet al.
1994). The diagnosis of stifle joint disorders is
generally based on a history of lameness, physi-
cal examination, and radiography. For decades,
radiography has been the most often-used
medical imaging technique to diagnose stifle
disorders and has been proven very useful in
its clinical work-up (Marino & Loughin 2010).
A stress radiographic technique, based on the
clinical tibial compression test, has been intro-
duced in an attempt to improve the diagnostic
accuracy of clinical evaluation of craniocaudal
instability. It is a valuable asset in the diagno-
sis of canine stifle instability due to cruciate
ligament rupture (CR). It is a useful technique
to prove (or disprove) a tentative diagnosis of
CR, especially when there is a lack of cranial
drawer sign on clinical examination, and is able
to detect complete or partial CR (de Roosteretal.
1998; de Rooster & van Bree 1999). In contrast to
radiography, where there is summation of the
overlying structures, cross-sectional imaging
such as computed tomography (CT) allows
examination of the internal joint structures

without superimposition. CT has proven to be

extremely sensitive in demonstrating calcified

or bony structures, and also allows demon-

stration of the soft tissues when the correct

windowing has been applied (Soleret al.2007).

Indications for using CT

These include:

 Developmental disorders: Osteochondrosis

(OC)/osteochondritis dissecans (OCD),

medial or lateral patellar subluxation or

luxation.

 Traumatic: fractures of the tibial plateau,

femoral condylar fracture, fracture of the

patella, muscular hematoma, collateral liga-

ment lesion, patellar tendon lesion, gastroc-

nemius avulsion, avulsion fractures of intra-

articular ligaments including the CrCL and

the caudal cruciate ligament (CaCL), the

popliteus, the extensor digitorum longus.

 Degenerative: CR, osteoarthritis, enthe-

siopathies.

 Neoplastic: including synovial cell sarcoma,

osteosarcoma, lipoma.

 Infection.

 Miscellaneous:including subchondral bone

cysts.

Advances in the Canine Cranial Cruciate Ligament, Second Edition. Edited by Peter Muir. © 2018 ACVS Foundation.
This Work is a co-publication between the American College of Veterinary Surgeons Foundation and Wiley-Blackwell.

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