Evaluation of a circumferential femoral head osteophyte as an early indicator of osteoarthritis characteristic of canine hip dysplasia in dogs.
OBJECTIVE
To determine the relationship between a circumferential femoral head osteophyte (CFHO) and osteoarthritis characteristic of canine hip dysplasia, and to ascertain whether CFHO, like osteoarthritis, varies between diet-restricted and control-fed dogs.


METHODS
Longitudinal cohort study.


METHODS
48 Labrador Retrievers.


METHODS
Dogs were paired by size, sex, and litter and assigned to 1 of 2 equal groups at 2 months of age. The control-fed group was fed ad libitum, and the diet-restricted group was fed 25% less on a pairwise basis of the same diet for life. The dogs' hip joints were radiographed yearly for life. Each radiograph was evaluated for radiographic signs of osteoarthritis characteristic of hip dysplasia and for the presence and severity of a CFHO.


RESULTS
41 of the 48 (85.4%) dogs had a CFHO, which was detected at a median age of 5.4 years, and 33 of those 41 (80.5%) developed radiographic evidence of osteoarthritis. Nineteen (79.2%) dogs in the diet-restricted group and 22 (91.7%) in the control-fed group had a CFHO at a median age of 9 and 3 years, respectively. Of the dogs with a CFHO, 12 (63.2%) in the diet-restricted group and 20 (90.0%) in the control-fed group developed radiographic evidence of osteoarthritis characteristic of hip dysplasia at a median age of 11 and 6.5 years, respectively.


CONCLUSIONS
Results indicated a relationship between the CFHO and subsequent development of radiographic signs of osteoarthritis. If a CFHO is present in Labrador Retrievers, it might be considered an early indicator of osteoarthritis.
Szabo
Stephanie D
SD
Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104-6010, USA.
Biery
Daryl N
DN
Lawler
Dennis F
DF
Shofer
Frances S
FS
Powers
Michelle Y
MY
Kealy
Richard D
RD
Smith
Gail K
GK
D000367:Age Factors; D000375:Aging; D000818:Animals; D015331:Cohort Studies; D004038:Diet, Reducing / Q000662:veterinary*; D004283:Dog Diseases / Q000000981:diagnostic imaging / Q000178:diet therapy* / Q000517:prevention & control*; D004285:Dogs; D005260:Female; D005270:Femur Head / Q000000981:diagnostic imaging / Q000473:pathology; D006619:Hip Dysplasia, Canine / Q000178:diet therapy* / Q000517:prevention & control* / Q000532:radiotherapy; D008137:Longitudinal Studies; D008297:Male; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging / Q000178:diet therapy / Q000517:prevention & control / Q000662:veterinary*; D011859:Radiography; D012720:Severity of Illness Index