Premium
Ex vivo Contact Mechanics and Three‐Dimensional Alignment of Normal Dog Elbows after Proximal Ulnar Rotational Osteotomy
Author(s) -
Cuddy Laura C.,
Lewis Daniel D.,
Kim Stanley E.,
Conrad Bryan P.,
Banks Scott A.,
Horodyski MaryBeth,
Fitzpatrick Noel,
Pozzi Antonio
Publication year - 2012
Publication title -
veterinary surgery
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.652
H-Index - 79
eISSN - 1532-950X
pISSN - 0161-3499
DOI - 10.1111/j.1532-950x.2012.01038.x
Subject(s) - anatomy , elbow , cadaveric spasm , osteotomy , medicine , biomechanics , compartment (ship) , elbow flexion , orthodontics , cadaver , oceanography , geology
Objective To evaluate the effect of proximal ulnar rotational osteotomy ( PURO ) on the contact mechanics and 3‐dimensional (3 D ) alignment of cadaveric normal dog elbows. Study Design Ex vivo biomechanical study. Animals Unpaired thoracic limbs from 12 dogs (mean ± SD weight, 26 ± 4 kg). Methods PURO consisted of a transverse osteotomy with 30° external rotation of the proximal segment. With the limb under 200 N axial load, contact area ( CA ), mean contact pressure ( CP ) and peak contact pressure ( PCP ) were measured using digital pressure sensors in the medial and lateral compartments and 3D static elbow poses were obtained, before and after PURO . Each specimen was tested at 115°, 135°, and 155° elbow flexion, with the antebrachium in neutral rotation, in 28° supination, and in 16° pronation. Repeated measures ANOVAs with post‐hoc Bonferroni ( P ≤ .05) were performed. Results PURO caused significant changes, mostly at 135° elbow flexion and neutral antebrachial rotation, characterized by decreased CP (10%) and PCP (10%) in the medial compartment, and increased CP (27%) and PCP (23%) in the lateral compartment. The apex of the medial coronoid process translated 3.4 mm caudally, 1.7 mm abaxially, and rotated 1.8° externally relative to the radial head. Humeroradial varus angulation reduced by 6.7°. Conclusions In limited poses, PURO displaces the medial coronoid process caudally and abaxially and shifts contact pressures towards the lateral elbow compartment by decreasing varus angulation.