Evaluation of multiple radiographic predictors of cartilage lesions in the hip joints of eight-month-old dogs.
OBJECTIVE
To determine the radiographic methods that best predict the development of osteoarthritis in the hip joints of a cohort of dogs with hip dysplasia and unaffected dogs.


METHODS
205 Labrador Retrievers, Greyhounds, and Labrador Retriever-Greyhound crossbred dogs.


METHODS
Pelvic radiography was performed when the dogs were 8 months old. Ventrodorsal extended-hip, distraction, and dorsolateral subluxation (DLS) radiographs were obtained. An Orthopedic Foundation for Animals-like hip score, distraction index, dorsolateral subluxation score, and Norberg angle were derived from examination of radiographs. Osteoarthritis was diagnosed at the time of necropsy in dogs > or = 8 months of age on the basis of detection of articular cartilage lesions. Multiple logistic regression was used to determine the radiographic technique or techniques that best predicted development of osteoarthritis.


RESULTS
A combination of 2 radiographic methods was better than any single method in predicting a cartilage lesion or a normal joint, but adding a third radiographic method did not improve that prediction. A combination of the DLS score and Norberg angle best predicted osteoarthritis of the hip joint or an unaffected hip joint. All models that excluded the DLS score were inferior to those that included it.


CONCLUSIONS
A combination of the DLS score and Norberg angle was the best predictor of radiographic measures in 8-month-old dogs to determine whether a dog would have normal or osteoarthritic hip joints.
Todhunter
Rory J
RJ
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Grohn
Yjo T
YT
Bliss
Stuart P
SP
Wilfand
Ashley
A
Williams
Alma J
AJ
Vernier-Singer
Margaret
M
Burton-Wurster
Nancy I
NI
Dykes
Nathan L
NL
Wu
Rongling
R
Casella
George
G
Acland
Gregory M
GM
Lust
George
G
D000818:Animals; D002357:Cartilage Diseases / Q000000981:diagnostic imaging / Q000662:veterinary*; D004285:Dogs; D006619:Hip Dysplasia, Canine / Q000000981:diagnostic imaging*; D008962:Models, Theoretical; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000662:veterinary*; D011237:Predictive Value of Tests; D011859:Radiography