Risk factors affecting the outcome of surgery for atlantoaxial subluxation in dogs: 46 cases (1978-1998).
OBJECTIVE
To identify risk factors for successful surgical management of dogs with atlantoaxial subluxation (AAS).


METHODS
Retrospective study.


METHODS
46 dogs managed surgically for AAS.


METHODS
Age at onset of clinical abnormalities, duration of clinical abnormalities prior to surgery, radiographic appearance of the dens, type (dorsal or ventral procedure) and number (1 or 2) of surgeries performed, grade of postoperative atlantoaxial joint reduction, and neurologic status prior to surgery (preoperative), when dogs were discharged from the hospital (postoperative), and during a follow-up evaluation (final) were obtained from the dogs' medical records. Risk factors for surgical success and degree of neurologic improvement were identified and analyzed for predictive potential.


RESULTS
Age at onset of clinical abnormalities < or = 24 months was significantly associated with greater odds of a successful first surgery and final outcome and a lower postoperative neurologic grade. Duration of clinical abnormalities < or = 10 months was significantly associated with greater odds of a successful final outcome and a lower final neurologic grade. A preoperative neurologic grade of 1 or 2 was significantly associated with a lower final neurologic grade. Potential risk factors that did not affect odds of a successful outcome included type of surgery performed, grade of atlantoaxial joint reduction, radiographic appearance of the dens, or need for a second surgery.


CONCLUSIONS
Age at onset of clinical abnormalities, duration of clinical abnormalities prior to surgery, and preoperative neurologic status are risk factors for success of surgical management of AAS in dogs.
Beaver
D P
DP
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610-0126, USA.
Ellison
G W
GW
Lewis
D D
DD
Goring
R L
RL
Kubilis
P S
PS
Barchard
C
C
D000818:Animals; D001268:Atlanto-Axial Joint / Q000601:surgery; D004283:Dog Diseases / Q000601:surgery*; D004285:Dogs; D005260:Female; D005500:Follow-Up Studies; D004204:Joint Dislocations / Q000601:surgery / Q000662:veterinary*; D008297:Male; D012086:Reoperation / Q000662:veterinary; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome