Proximal tibial axis
Proximal tibial axis
- Acronym: PTA
Definition
The proximal tibial axis is a landmark used to assess the anatomy of the tibia and its modification in predisposed dogs or dogs at risk for cranial cruciate ligament rupture. It is determined from a mediolateral radiograph of the tibia. The X-ray beam is centered at the stifle joint. Positioning is considered satisfactory if the medial condyle and lateral condyle are superimposed.
The proximal tibial axis is defined as the line joining the cranial aspect of the medial tibial condyle proximally and the craniocaudal midpoint at the distal aspect of the tibial crest measured along a line perpendicular to the anatomic tibial axis distally.
References
Osmond CS, Marcellin-Little DJ, Harrysson OL, Kidd LB. Morphometric assessment of the proximal portion of the tibia in dogs with and without cranial cruciate ligament rupture. Vet Radiol Ultrasound. 2006 Mar-Apr;47(2):136-41. doi: 10.1111/j.1740-8261.2006.00119.x. PMID: 16553144.