Page 389 - Canine Lameness

20.5 Hip Dysplasia 361

Pain on HIP EXTENSION

Pain on hip
abduction and YES
flexion?
NO

Pain on lumbosacral Pain on stifle Pain on stretching of
palpation hyperextension individual hip flexors

Indicates
NEUROLOGIC Indicates STIFLE Indicates MUSCLE Indicates HIP
pathology
pathology
pathology
pathology
Perform further palpation Perform further palpation Perform further palpation HIP REGION
and diagnostics of L4-S2 and diagnostics of stifle (e.g. and diagnostics of hip flexors Perform further palpation
region (e.g. neuro exam, drawer, thrust testing, and (e.g. stretching, ultrasound, and diagnostics of hip joint
(e.g. radiographs)
radiographs, and MRI) radiographs) and MRI)
Common DD: Common DD: Common DD: Common DD:
Lumbosacral disease Cruciate disease Iliopsoas myopathy Hip osteoarthritis

Figure 20.8 Algorithm to differentiate the four differential diagnoses for pain on hip extension: hip, stifle,
neurologic, or muscular pathology.

motion, it is suggestive of laxity of the joint. The Ortolani test may be inaccurate in dogs <4 months
of age; however, Gatineau et al. (2012) found that dogs with evidence of hip OA at 2 years of age all
had a positive Ortolani test at 6 months of age. On the other hand, only 50% of dogs with a positive
Ortolani test at 6 months of age went on to develop radiographic hip OA at 2 years of age. Thus, a
positive Ortolani test has a strong sensitivity, but poor specificity at 6 months of age for predicting
the development of radiographic OA at 2 years of age (Gatineau et al. 2012).
In comparison to younger dogs suffering mainly from laxity, older dogs will present primarily
with signs of OA including a weight-bearing lameness that is typically bilateral, though one limb
may be worse. They will have generalized pelvic limb muscle atrophy, decreased range of motion
(particularly in extension and abduction) possibly with palpable crepitus, and in cases with severe