Comparison of two radiographic techniques for evaluation of hip joint laxity in 10 breeds of dogs.
OBJECTIVE
To evaluate hip joint laxity in 10 breeds of dogs via 2 radiographic techniques.


METHODS
500 clinically normal dogs.


METHODS
Prospective study.


METHODS
Radiographs obtained via routine hip joint evaluations performed in sedated dogs of 10 popular breeds were randomly selected from a database. Measurements of distraction index (DI) and hip-extended index (HEI) on 1 hip joint radiograph randomly chosen from each dog were made.


RESULTS
Mean age of dogs was 20.7 months. Mean HEI was 0.17 (range, 0.0 to 0.72) and mean DI was 0.44 (range, 0.07 to 0.96). Borzois had uniformly tight hip joints as judged by use of both methods and were considered the gold standard by which hip joint laxity was judged (all Borzois had DI < or = 0.32). Overall, DI was significantly greater than HEI. Within each breed, mean DI was always greater than mean HEI. Significant differences were detected among breeds for HEI; however, compared with DI, the magnitude of differences among breeds was less.


CONCLUSIONS
Distraction radiography detected the greatest range and magnitude of passive hip laxity in the 10 breeds of dogs. The difference in values between breeds known to have high prevalence of canine hip dysplasia and those in Borzois was greater for DI than for HEI. Breeds must be evaluated individually because of inherent differences in hip joint laxity.
Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104-6010, USA.
Amy S
AS
Kapatkin
Thomas P
TP
Gregor
Kendra
K
Hearon
Robert W
RW
Richardson
Pamela J
PJ
McKelvie
Hilary H
HH
Fordyce
Gail K
GK
Smith
D000818:Animals; D003937:Diagnosis, Differential; D004285:Dogs; D005260:Female; D006619:Hip Dysplasia, Canine / Q000000981:diagnostic imaging* / Q000473:pathology; D006621:Hip Joint / Q000000981:diagnostic imaging* / Q000473:pathology; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*; D008297:Male; D011446:Prospective Studies; D011859:Radiography; D012016:Reference Values; D013045:Species Specificity