Abstract
Objective The aim of this study was to report the average tibial plateau angle (TPA) from a
large sample of dogs and to determine if breed or gonadectomy had a significant association
with abnormal TPA.
Study Design This was a retrospective case study.
Materials and Methods Medical records from 2006 to 2015 were reviewed for dogs that were diagnosed with
cranial cruciate ligament (CrCL) rupture and underwent dynamic surgical stabilization.
Signalment, examination findings, preoperative TPA and surgical report were reviewed.
Results A total of 3,249 dogs underwent CrCL stabilization surgery from 2006 to 2015. Of
the 3,249 dogs, 3,054 dogs met the inclusion criteria for a total of 3,922 stifles
to be evaluated. The average preoperative TPA was 29° ± 3.7°. Average breed-specific
preoperative TPA ranged from 27° to 35.1°, with four breeds having significantly lesser
TPA and four breeds significantly greater TPA than the overall mean of dogs. Neutered
dogs had a higher TPA of 28.87° ± 3.8° than non-neutered dogs with an average TPA
of 26.88° ± 4.0°, p < 0.001. There was not a significant difference in average TPA between females and
males, regardless of the neuter status.
Conclusion and Clinical Relevance Our reported preoperative TPA in a large sample of dogs is higher than what has been
previously published. In reviewing 3,922 stifles, the average preoperative TPA was
29°. We report the average preoperative TPA in specific breeds and report that neutered
dogs have a significantly higher TPA than intact dogs. This updated information may
guide clinicians in management decisions regarding treatment for CrCL rupture.
Keywords
cruciate ligament disease - tibial plateau angle - dog - breed - gonadectomy
