Radiographic, computed tomographic, and arthroscopic findings in Labrador Retrievers with medial coronoid disease

Objective To describe the radiographic, computed tomographic (CT), and arthroscopic findings in different age groups of Labrador Retrievers diagnosed with medial coronoid disease (MCD), and to compare the ulnar subtrochlear sclerosis (STS) observed on radiographs with the ratio between the mean attenuation of the ulnar subtrochlear bone and the mean attenuation of the cortical bone measured on CT. Study Design Prospective clinical study. Animals Dogs (n = 31; 31 elbow joints) and 6 healthy Labrador Retrievers (6 elbow joints). Methods Radiographic, CT, and intraoperative arthroscopic images (2008–2012) were evaluated. Statistical analysis was performed for the descriptive study to evaluate the difference in findings between age groups and to investigate the correlation between radiographic and CT evaluated ulnar STS. Results Ulnar STS (87.6%) was the most common radiographic findings in dogs ≤12 months and blurring of the cranial edge of the medial coronoid process (MCP; 66.7%) was the most common radiographic findings in dogs >12 months. MCP fragmentation was the most common CT finding in both age groups (93.8% [≤12 months]; 66.7% [>12 months]). A displaced fragment (68.8%) was the most common arthroscopic finding in dogs ≤12 months whereas osteochondromalacia (53.3%) was the most common finding in dogs >12 months. Sensitivity of radiography in detecting MCD was 93.8% (≤12 months) and 73.3% (>12 months) and for CT was 93.8% (≤12 months) and 66.7% (>12 months). Radiographic evaluated ulnar STS was strongly correlated with CT evaluated ulnar STS. Conclusion Wide ranges of radiographic, CT, and arthroscopic findings in Labrador Retrievers diagnosed with medial coronoid disease were identified

Dietary Vitamin D Supplementation during Early Growth is not Protective for Medial Coronoid Disease Development in Labradors

Introduction: Medial coronoid disease (MCD) is a common heritable disease in young large-breed dogs and is characterized by fissures and/or fragmentation of the medial coronoid process (MCP), cartilage, and/or subchondral bone. MCD development has also been attributed to disturbed endochondral ossification. Vitamin D influences skeletal development and endochondral ossification by stimulating the terminal differentiation of chondrocytes and the mineralization of cartilage and the newly formed osteoid. The aim of this study was to investigate whether vitamin D supplementation of the standard puppy diet given to puppies after weaning can prevent the development of medial coronoid disease (MCD) by stimulating endochondral ossification, including terminal differentiation of chondrocytes, and mineralization of the cartilaginous template of the developing medial cornoid process (MCP). Animals, material and methods: A litter of Labrador puppies was on purpose bred by mating a dam and a sire with MCD; these dogs are known to produce offspring with MCD. The puppies received a diet supplemented with 50,000 IU vitamin D per kg as fed. Development of MCD was monitored by computed tomography (CT) and plain radiographs every two weeks, and post-mortem by microCT, necropsy, histology, and immunohistochemistry and compared with data from a previous study. Results and discussion: Vitamin D supplementation did result in increased plasma levels of 25- vitamin D and 1.25-vitamin D, but did not prevent development of MCD in growing Labradors. Instead, vitamin D supplementation resulted in increased collagen X staining ofthe MCP and irregular costal growth plates, demonstrating disturbed endochondral ossification. Conclusion: Vitamin D supplementation does not prevent MCD development. Other causes for MCD rather than relative vitamin D deficiency causing disturbed endochondral ossification are more likely

Dietary Vitamin D Supplementation during Early Growth is not Protective for Medial Coronoid Disease Development in Labradors

Introduction: Medial coronoid disease (MCD) is a common heritable disease in young large-breed dogs and is characterized by fissures and/or fragmentation of the medial coronoid process (MCP), cartilage, and/or subchondral bone. MCD development has also been attributed to disturbed endochondral ossification. Vitamin D influences skeletal development and endochondral ossification by stimulating the terminal differentiation of chondrocytes and the mineralization of cartilage and the newly formed osteoid. The aim of this study was to investigate whether vitamin D supplementation of the standard puppy diet given to puppies after weaning can prevent the development of medial coronoid disease (MCD) by stimulating endochondral ossification, including terminal differentiation of chondrocytes, and mineralization of the cartilaginous template of the developing medial cornoid process (MCP). Animals, material and methods: A litter of Labrador puppies was on purpose bred by mating a dam and a sire with MCD; these dogs are known to produce offspring with MCD. The puppies received a diet supplemented with 50,000 IU vitamin D per kg as fed. Development of MCD was monitored by computed tomography (CT) and plain radiographs every two weeks, and post-mortem by microCT, necropsy, histology, and immunohistochemistry and compared with data from a previous study. Results and discussion: Vitamin D supplementation did result in increased plasma levels of 25- vitamin D and 1.25-vitamin D, but did not prevent development of MCD in growing Labradors. Instead, vitamin D supplementation resulted in increased collagen X staining ofthe MCP and irregular costal growth plates, demonstrating disturbed endochondral ossification. Conclusion: Vitamin D supplementation does not prevent MCD development. Other causes for MCD rather than relative vitamin D deficiency causing disturbed endochondral ossification are more likely