Objective—To estimate prevalence of canine hip dysplasia
(CHD) in Golden Retrievers and Rottweilers and
identify sources of bias in published reports.
Animals—200 clinically normal Golden Retrievers and
140 clinically normal Rottweilers between 24 and 60
months of age referred for hip evaluation (group 1) and
93 clinically normal dogs evaluated for Orthopedic
Foundation for Animals (OFA) hip certification (group 2).
Procedure—Hip-extended pelvic radiographs from
group 1 dogs were screened for CHD. Radiographs
were evaluated twice; the first interpretation used an
OFA-type subjective 7-point scoring system, and the
second included the caudolateral curvilinear osteophyte
as an additional sign of degenerative joint disease.
The OFA submission rate of group 2 dogs was
determined from the number of official reports
returned from the OFA.
Results—Prevalence of CHD in Golden Retrievers
ranged from 53% to 73% and in Rottweilers ranged
from 41% to 69%. Among dogs referred for OFA evaluation,
radiographs from 49 (53%) were submitted to
OFA. Of submitted radiographs, 45 (92%) were normal;
of radiographs not submitted, 22 (50%) were
normal. Radiographs with normal-appearing hips
were 8.2 times as likely to be submitted to the OFA.
Compared with Golden Retrievers, Rottweiler radiographs
were significantly more likely to be submitted
for OFA certification.
Conclusions and Clinical Relevance—Prevalence of
CHD in these 2 breeds may be much higher than previously
reported in the United States. Results suggest
substantial bias in the OFA database, which causes
lower estimates of prevalence of CHD. (J Am Vet Med