Average Tibial Plateau Angle of 3,922 Stifles Undergoing Surgical Stabilization for Cranial Cruciate Ligament Rupture

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.

Correlates of estimated lifetime cruciate ligament survival inform potential rupture risk reduction strategies: findings from the Exceptional Aging in Rottweilers Study

“…This delay in skeletal maturity might be associated with increased opportunity for errors in skeletal modeling that render the cranial cruciate ligament more susceptible to rupture. Two studies have demonstrated that the occurrence of increased tibial plateau angle (TPA), a phenotype that may be associated with increased risk for CCL rupture, is increased by gonad removal 41 , 42 . Although reported differences between TPA in cases and non-cases are inconsistent 32 , 34 , 35 , 43 – 47 , the finding that increased TPA may be a gonad-sensitive phenotype raises the possibility that other morphometric variables, such as intercondylar notch width 48 or femoral anteversion angle 31 , may also be sensitive to early endocrine disruption.…”