Preliminary evaluation of a custom load-application technique for carpal stress radiography: comparison between standing and sedated dogs.

Objective: To establish the feasibility of a novel technique for performing carpal stress radiography and to compare carpal angles between standing and sedated stress radiography at 2 applied loads on standard and oblique projections in normal dogs.

Methods: In this prospective, exploratory, analytical study, 4-view standing radiographs were performed at 30% body weight (BW) and 60% BW weightbearing force. Sedated 4-view carpal radiographs were performed utilizing a custom-built positioning device at 2 tensile loads extrapolated from the 30% and 60% BW standing mediolateral radiographs. Carpal angles on standing and sedated radiographs were measured by a board-certified radiologist. Carpal angle measurements were compared within and between the standing and sedated radiographs for the 2 applied loads.

Results: Data were collected from bilateral carpi of 5 research dogs (10 carpi). With both standing and stress radiography, the applied load had a significant effect on carpal angle. Medial stress radiography on all projections and lateral stress radiography on dorsopalmar projections had greater changes in carpal angles compared with standing radiography. Greater changes in carpal angle with increasing tension were present on palmar stress radiography and medial stress radiography but not lateral stress radiography.

Conclusions: The study results confirm the feasibility of the custom-built positioning device and objective tensile load application for the acquisition of canine carpal stress radiography.

Clinical relevance: This study describes a novel technique for performing carpal stress radiography and provides initial data for study design refinement for future research projects aimed at establishing standardized methods for acquiring and interpreting carpal stress radiography in dogs.