Page 234 - Canine Lameness

206 14 Elbow Region

Treatment of MCD frequently includes arthroscopic debridement, although surgical treatment
has been questioned by some since arthritis progression is expected even with surgical intervention
(Burton et al. 2011; Barthélémy et al. 2014; Dempsey et al. 2019). Others have concluded that
arthroscopy is superior to medical management and treatment via arthrotomy (Evans et al. 2008). The
lack of definitive information regarding the ideal treatment is likely related to a lack of objective
outcome measures and the wide variability seen with the disease complex of MCD (Fitzpatrick and
Yeadon 2009). If traditional medical management is exhausted, novel treatment options such as
joint injections, elbow resurfacing, load-shifting procedures, or total elbow replacement may therefore
be considered despite a lack of sufficient long-term data to support their use (Coppieters et al. 2015).

14.6.1 Signalment and History

MCD is considered a developmental disease and diagnosed most commonly in juvenile patients.
Nonetheless, some patients may not present until later in life when symptoms arise due to second-
ary elbow osteoarthritis. Large-/giant-breeds are predisposed, with Labrador Retrievers and
Bernese Mountain Dogs most frequently affected. However, the disease has also been reported in
smaller dogs (such as Dachshund and French Bulldog).
ELBOW REGION 14.6.2 Physical Exam

Diagnosis of MCD is usually based on the following features: reduced ROM, discomfort on hyper-
flexion and -extension, joint effusion, and periarticular swelling (in chronic cases with secondary
degenerative changes). Patients with MCD attempt to redirect the forces to the lateral compart-
ment (to off-load the medial compartment), resulting in a typical bow-legged stance with external
rotation of the limb (Figure 14.5E). Although it is not always palpable, joint effusion can be identi-
fied caudal to the humeral epicondyles (Figure 14.6). Diagnosis of MCD based on a pain response
is difficult since some patients appear to show little to no response to palpation. To increase the
odds of eliciting a pain response, the elbow should be evaluated during flexion, during hyperextension,
and while performing a manipulation known as the “Campbell’s test.” This test was originally
developed for detection of collateral ligament disruption (Farrell et al. 2007), but it can be particu-
larly useful when screening for ED in young animals since other features of chronic elbow OA (e.g.
periarticular swelling, reduced ROM, etc.) may not be present. For this test, the limb is pronated
and supinated while keeping the carpus and elbow flexed at approximately 90° while applying
gentle pressure at the area of the medial aspect of the coronoid process. This area is located approx-
imately 1 cm distal to the medial epicondyle (which is easily palpated when the elbow is extended)
in large-breed dogs. Hyperextension of the joint is performed by pushing cranially at the level of
the elbow joint while keeping the shoulder in a consistent position (i.e. the ROM of the shoulder
should not change when the elbow is extended). Pain on flexion can be tested while the animal is
standing by simply flexing the elbow joint and evaluating for symptoms of pain and whether the
dog “moves” away and hops towards the contralateral side (Videos 14.2 and 3.1).

Video 14.2

Clinical exams of elbow examination for detection of elbow pathology and how to differentiate elbow
from shoulder pain.