Canine Hip Joint Conformation
Consensus reports on pelvic radiographs from the OFA contain information for
serious and concerned owners. The consensus is the result of independent review
by three veterinary radiologists and is reported as one of the following
categories. The first three are considered within normal radiographic limits for
age and breed and are eligible for assignment of an OFA breed number if the dog
was 24 months of age or older at the time of radiography.
- EXCELLENT HIP JOINT CONFORMATION superior hip joint conformation as
compared with other individuals of the same breed and age.
- GOOD HIP JOINT CONFORMATION well formed hip joint conformation as compared
with other individuals of the same breed and age.
- FAIR HIP JOINT CONFORMATION minor irregularities of hip joint conformation
as compared with other individuals of the same breed and age.
The following categories are not eligible for an OFA breed number:
- BORDERLINE HIP JOINT CONFORMATION Marginal hip joint
conformation of indeterminate status with respect to hip dyslasia at this
time. A repeat study is recommended in 6-8 months.
- MILD HIP DYSPLASIA radiographic evidence of minor dysplastic change of the
hip joints.
- MODERATE HIP DYSPLASIA well defined radiographic evidence of dysplastic
changes of the hip joints.
- SEVERE HIP DYSPLASIA radiographic evidence of marked dysplastic changes of
the hip joints.
Hip joint conformation (phenotype) is the radiographic appearance of the hip
joints and is the outcome of interaction between a dog's hereditary make-up
(genotype) and its environment. Hip joint conformation can be represented as a
range from excellent to very dysplastic and shades in between these two ends of
the spectrum. Traits such as this are referred to as quantitative characters and
are thought to depend upon the interaction of many genes (polygenic).
Modern breeds of dogs vary widely in body size and shape and in pelvic
conformation. Because of these differences, OFA classifications are based on
comparisons among other individuals of the same breed and age. Knowledge of a
dog's pelvic phenotype can be a valuable guide for the breeder in selection
against hip dysplasia and understanding a dog's pelvic phenotype can be a useful
means of estimating an individual dog’s potential for an active working life.
