Radial torsion in dogs with medial compartment disease

Abstract

Objective To evaluate the magnitude and direction of radial torsion (RT) in dogs with medial compartment disease (MCD). Study design Case‐control study. Sample population Twenty‐eight healthy dogs and 28 dogs with confirmed MCD. Methods Computed tomography images of each dog's antebrachium were evaluated. Radial torsion was measured by using previously described landmarks on the proximal and distal radius. Differences between groups were tested with Student's t tests and Wilcoxon rank‐sum tests. Results Healthy dogs had a mean RT angle of 3.44° (range, 1.28°‐5.44°). Dogs with MCD had a mean RT angle of 11.84° (range, 2.31°‐26.55°). Both groups included similar proportions of dogs with external (76% vs 77%) and internal (24% vs 23%) torsion. The direction of torsion (P = .21 and P = .69) did not appear to affect the magnitude of the RT angle. Conclusion Dogs with MCD had an increased RT angle compared with healthy controls. The direction of torsion varied similarly between groups regardless of the disease status of dogs in this study. Clinical significance The fourfold increase in the RT seen in dogs with MCD may contribute to the rotational overload proposed recently, potentially modifying the orientation of the elliptical radial head and the ligaments crossing the elbow joint.

Correction of antebrachial angulation‐rotation deformities in dogs with oblique plane inclined osteotomies

“…For the purposes of this study, we use the term radial torsion to signify malangulation of the radius in the transverse plane and use the term rotation to include malalignment of the manus relative to the distal brachium in the transverse plane . This differentiation is pertinent because malalignment of the limb in the transverse plane can be a combination of radial head rotation, also referred to as elbow rotation, radial torsion, and carpal rotation …”