Front Matter

376 Canine Sports Medicine and Rehabilitation

with a grade I–III patellar luxation. Grade IV
MPL is generally associated with a significant
limb deformity and moderate to severe lameness
is common (Alam et al., 2007). An acute exacer­
bation of lameness in dogs with MPL should
raise suspicion for CCLR (Campbell et al., 2010).
Patellar luxation is diagnosed by physical
examination. Radiographs are often recom­
mended to assess for degenerative joint disease
and to evaluate bony conformation for surgical
planning (L’Eplattenier & Montavon, 2002a).
Previous recommendations in assessment of a
true craniocaudal radiograph have been shown
to be inaccurate (Aiken & Barnes, 2014) leading
to the suggestion that CT is the gold standard
for assessment of femoral and tibial alignment
in cases of patella luxation.
Computed tomography is useful in dogs
with severe conformational deformities to assist
with surgical planning (Towle et al., 2005)
(Figure 14.27), and recent increased availability
of CT has allowed for validation of techniques

to measure femoral and tibial alignment

(Barnes et al., 2015; Oxley et al. 2013).

Treatment

Nonsurgical management is recommended for

animals with grade I and asymptomatic grade

II patellar luxation (L’Eplattenier & Montavon,

2002b). The decision to pursue surgery is based

upon frequency and severity of lameness,

functional limitations, and the opportunity to

decrease the likelihood of CCL tears. Several

surgical techniques that aim to realign the

quadriceps mechanism and decrease the

abnormal biomechanical stresses placed on

the patella have been developed (Johnson et al.,

2001; L’Eplattenier & Montavon, 2002b; Arthurs

& Langley‐Hobbs, 2006; Swiderski & Palmer,

2007; Langenbach & Marcellin‐Little, 2010;

Yeadon et al., 2011). Usually several techniques

are employed in combination in a single patient.

(A) (B)

101.8* (2D)

67.6 mm (2D)

216.2mm (2D)

Figure 14.27 (A, B) CT is useful in dogs with severe conformational deformities to assist with surgical planning.