Might KR, Hanzlik KA, Case JB, Duncan CG, Egger EL, Rooney MB, Duerr FM. Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA Animal Urgent Care and Specialty Group, Escondido, CA College of Veterinary Medicine and Biomedical Sciences, James L. Voss Veterinary Tea Vet Surg 2011 May 40 3 321-6 Objective: To determine the effect of proximal ulnar osteotomy (PUO), distal ulnar osteotomy (DUO), and DUO with release of the interosseous ligament (DOLR) on displacement of the proximal ulna at the radioulnar joint. Study Design: Experimental mechanical study. Sample Population: Cadaveric, skeletally mature canine thoracic limb pairs (n=11). Methods: Thoracic limbs disarticulated at the elbow were randomly assigned to 1 of 2 groups: (A) limbs were tested with no treatment (NOTX), then with PUO; (B) limbs were tested with DUO followed by DOLR. A distraction force was applied to the proximal ulna with the distal limb secured in a frame, and displacement of the proximal ulnar segment at the radioulnar joint was recorded. Results: Mean displacement was 0.36 mm (95% confidence interval [CI]: 0-1.12 mm) in the NOTX group, 4.68 mm (95% CI: 3.82-5.55 mm) for PUO limbs, 0.95 mm (95% CI: 0.52-1.39 mm) for the DUO group, and 4.36 mm (95% CI: 3.71-5.02 mm) for the DOLR group. Mean ulnar displacement of the DOLR group was significantly different compared with the DUO group, but there was no significant difference between the PUO and DOLR groups. Conclusions: No significant difference was observed in displacement of the proximal ulnar segment after DOLR compared with PUO.

• Deformity
• Distal Extremities
• Elbow