This study aimed to assess the stability and safety of 1.5- & 2.0-mm hybrid locking plates compared to conventional 1.5 mm locking plates for managing radius and ulnar fractures in small and toy-breed dogs. The hybrid locking plate features two 2.0 mm screw holes designed for distal segment and six 1.5 mm screw holes for proximal segments. We conducted mechanical tests across three configurations targeting the distal segment of the radius: a conventional locking plate with three 1.5 mm screws, one with two 1.5 mm screws, and a hybrid locking plate with two 2.0 mm screws, using fracture gap model. Our findings indicate that the hybrid plates provided the highest mean stiffness and significantly reduced impulse values, suggesting enhanced stability and lower energy absorption. Specifically, stiffness values increased from 193.58 N/mm in the basic setup to 268.56 N/mm in the hybrid configuration, while impulse values decreased significantly across the groups, pointing to potential benefits in immediate post-operative stability. However, the fatigue cyclic tests highlighted no significant differences in survival rates among the groups, suggesting that further research is needed to validate these findings under more dynamic conditions. Consequently, these results underline the potential of 1.5- & 2.0-mm hybrid plates as a valuable tool for treating challenging fractures in small breeds, although further clinical trials are necessary to confirm their effectiveness in real-world scenarios.

OBJECTIVE: To identify and evaluate the lateral border zone by comparing the size and distribution of the abnormal signal area demonstrated by MR imaging with the infarct area revealed by pathological examination in a reperfused myocardial infarction cat model. MATERIALS AND METHODS: In eight cats, the left anterior descending coronary artery was occluded for 90 minutes, and this was followed by 90 minutes of reper-fusion. ECG-triggered breath-hold turbo spin-echo T2-weighted MR images were initially obtained along the short axis of the heart before the administration of contrast media. After the injection of Gadomer-17 and Gadophrin-2, contrast-enhanced T1-weighted MR images were obtained for three hours. The size of the abnormal signal area seen on each image was compared with that of the infarct area after TTC staining. To assess ultrastructural changes in the myocardium at the infarct area, lateral border zone and normal myocardium, electron microscopic examination was performed. RESULTS: The high signal area seen on T2-weighted images and the enhanced area seen on Gadomer-17-enhanced T1WI were larger than the enhanced area on Gadophrin-2-enhanced T1WI and the infarct area revealed by TTC staining; the difference was expressed as a percentage of the size of the total left ventricle mass (T2= 39.2 %; Gadomer-17 =37.25 % vs Gadophrin-2 = 29.6 %; TTC staining = 28.2 %; p < 0.05). The ultrastructural changes seen at the lateral border zone were compatible with reversible myocardial damage. CONCLUSION: In a reperfused myocardial infarction cat model, the presence and size of the lateral border zone can be determined by means of Gadomer-17- and Gadophrin-2-enhanced MR imaging.
Animal ; Cats ; Contrast Media ; Gadolinium ; Magnetic Resonance Imaging/*methods ; Mesoporphyrins/diagnostic use ; Metalloporphyrins/diagnostic use ; Myocardial Infarction/*pathology ; Myocardial Reperfusion ; Myocardium/pathology ; Support, Non-U.S. Gov't