Summary
Objectives: To describe the use of hemiepiphysiodesis for the treatment of proximal tibial deformities
in immature dogs and evaluate the effect on the mechanical medial proximal tibial
angle (mMPTA).
Methods: Skeletally immature dogs with proximal tibial deformities from three institutions
treated with hemiepiphysiodesis between March 2006 and January 2015 were included.
All dogs were required to have an mMPTA outside the previously published reference
range (93.3 ± 1.78°) preoperatively. Dogs were required to have radiographs or computed
tomography performed preoperatively and at least eight weeks postoperatively.
Results: A total of 19 dogs (n = 31 limbs) fulfilled the inclusion criteria. The mean mMPTA
was 102.5° ± 5.3° preoperatively and 92.4° ± 7.2° at the final re-evaluation. The
mean difference in mMPTA was -10 ± 5.1° (range, -1 to -19°; p <0.001). Overcorrection
was observed in 16 limbs and mMPTA remained above the reference range in nine limbs.
Rebound growth was observed in eight limbs where implant removal was performed.
Clinical significance: Hemiepiphysiodesis for the treatment of proximal tibial valgus is a technique that
allows for reduction in mMPTA and should be considered as an early treatment for immature
animals that are presented with proximal tibial deformities. Serial radiographs to
monitor for overcorrection should be performed. Implant removal should be considered
if overcorrection occurs, taking into consideration that rebound growth may be observed.
A Supplementary Table for this paper is available online at: http://dx.doi.org/10.3415/VCOT-15-12-0204
Keywords
Physis - hemiepiphysiodesis - dog - tibial valgus - transphyseal stapling
