Page 235 - Canine Lameness

14.6 Medial Compartment Disease 207

(A) (C) (E)

(B) (D) (F) ELBOW REGION

Figure 14.6 Examination to detect elbow dysplasia: (A) flexion of the elbow; (B) isolated hyperextension
of the elbow without hyperextension of the shoulder; (C, E) palpation of joint effusion caudal to the
humeral epicondyles; (D, F) the “Campbell’s test” is performed by pronating and supinating the limb while
keeping the carpus and elbow flexed at approximately 90° and applying gentle pressure to the area of the
medial aspect of the coronoid process.

14.6.3 Diagnostics
Unfortunately, establishing a diagnosis in the juvenile patient frequently requires advanced imag-
ing since radiographs may only show subtle changes. Such changes may include sclerosis of the
ulnar trochlear notch, an indistinct coronoid process, incongruity, and mild degenerative changes
(Figure 14.7). Once osteoarthritis is established, the diagnosis is easily accomplished with radiog-
raphy. Although a CT is generally recommended in juvenile patients to accomplish a diagnosis, it
is important to consider that even this modality is not 100% accurate with a reported specificity of
85–93% (Groth et al. 2009; Villamonte-Chevalier et al. 2015). Hence, the diagnosis of MCD may
require arthroscopy in addition to CT, particularly for cases that are suffering from cartilage
changes only (Coppieters et al. 2015). Additional diagnostic steps may include intra-articular injec-
tion of mepivacaine (Chapter 8). This diagnostic tool is helpful if a positive effect is observed (i.e.
to confirm the diagnosis of ED) but has been shown to have an approximately 10% chance of false-
negative results (Van Vynckt et al. 2012).