Chapter 20 Imaging in Canine Sports Medicine 507tissue falling between the impedance of air
and bone. This makes ultrasonography a good
diagnostic tool for the evaluation of soft tis-
sues but poor for air‐filled structures and
pathological changes behind or beneath the
surface of bone.
Ultrasonography is becoming more com-
monly used in diagnosing soft tissue injuries
and following tissue healing in canine
patients. Appropriate diagnosis with ultra-
sonography is operator‐dependent. Education
and experience are vital to develop the skills
necessary to use this increasingly requested
modality appropriately.
Any muscle, tendon, ligament, or joint sus-
pected of injury could be assessed via ultra-
sonographic evaluation. There are several
studies documenting normal ultrasonographic
anatomy in the dog, including most joints and
soft tissue structures (Kramer et al., 1997, 1999;
Long & Nyland, 1999; Knox et al., 2003; Lamb &
Wong, 2005; Liuti et al., 2007; Cannon &
Puchalski, 2008; Caine et al., 2009; Turan et al.,
2009; Marino & Loughin, 2010; Piórek &
Adamiak, 2010; Villamonte‐Chevalier et al.,
2015). Pathological conditions and their ultra-
sonographic appearance have also been docu-
mented (Kramer et al., 1997, 1999, 2001; Gnudi
& Bertoni, 2001; Knox et al., 2003; Mahn et al.,
2005; Nielsen & Pluhar, 2005; Vandevelde et al.,
2006; Cogar et al., 2008; Arnault et al., 2009;
Caine et al., 2009; Cook & Cook, 2009; Seyrek‐
Intas et al., 2009; Hittmair et al., 2011; Villamonte‐
Chevalier et al., 2015; Canapp et al., 2016; Cook,
2016). Studies report evaluation of extra‐articular
soft tissue structures such as the supraspinatus,
biceps, abductor pollicis longus, iliopsoas
muscle and tendon, menisci, patellar tendons,
Achilles tendon, and others (Kramer et al., 1997,
2001; Long & Nyland, 1999; Gnudi & Bertoni,
2001; Mahn et al., 2005; Nielsen & Pluhar, 2005;
Vandevelde et al., 2006; Cogar et al., 2008;
Arnault et al., 2009; Seyrek‐Intas et al., 2009;
Turan et al., 2009; Marino & Loughin, 2010;
Piórek & Adamiak, 2010; Hittmair et al., 2011;
Crema et al., 2015; Villamonte‐Chevalier et al.,
2015; Canapp et al., 2016; Cook, 2016; Guermazi
et al., 2017). Ultrasonography appears to be
less useful when evaluating bone and intra‐
articular structures deep to the bone surfaces
such as the cruciate ligaments. However, a
recent study suggests that both ultrasonography
and MRI, though imperfect, offer clinical use-
fulness for diagnosing medial meniscal lesions
in dogs (Franklin et al., 2017).Shoulder ultrasonographyThe canine shoulder is one of the most common
areas for diagnostic ultrasound evaluation due
to the lack of radiographic findings and the
incidence of tendon and ligament injury in this
location, especially in performance dogs. Of
primary interest are the supraspinatus and
biceps tendons as these structures have been
commonly implicated in lameness associated
with the shoulder (Fransson et al., 2005; Cogar
et al., 2008; Murphy et al., 2008; Lafuente et al.,
2009; Van Dyck et al., 2009; Schaefer et al., 2010;
Canapp et al., 2016; Cook, 2016).
Ultrasonographic findings in the supraspi-
natus tendon typically include an increase in
size, changes in fiber pattern, and mineraliza-
tion. When there is an increase in size of the
supraspinatus tendon, compression of the
adjacent biceps tendon into the biceps groove
is often identified due to anatomic proximity
(Figure 20.6). The echogenicity of the supraspi-
natus tendon can vary depending on the
degree and chronicity of the tendinopathy.
Acute injury, which is less commonly identi-
fied, will have a mixed echogenicity with
hypoechoic areas indicating more fluid presentFigure 20.6 Ultrasonographic image of the
supraspinatus tendon. The supraspinatus is markedly
enlarged and is compressing the biceps tendon into the
biceps groove (arrows). The biceps tendon has lost its
normal ovoid shape due to the compression.