Musculoskeletal Pathology quiz

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What is hemimelia? Cleft in paw extending to metacarpus of dogs and cats Lateral deviation of the distal portion ofa limb Increased number of digits Absence of one of the limb bones Fusion of digits Please select an option Incorrect. Ectrodactylia is a cleft in the paw extending to metacarpus of dogs and cats. The correct answer is that hemimelia is the absence of one of the limb bones. WikiVet Article: Developmental Incorrect. Lateral deviation of the distal portion of the limb is described as a valgus angular limb deformity. The correct answer is that hemimelia is the absence of one of the limb bones. WikiVet Article: developmental Incorrect. Polydactylia is an increased number of digits. The correct answer is that hemimelia is the absence of one of the limb bones. WikiVet Article: developmental Correct! Hemimelia is the absence of one of the limb bones. WikiVet Article: developmental Incorrect. Fusion of digits is called syndactylia. The correct answer is that hemimelia is the absence of one of the limb bones. WikiVet Article: developmental

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Which condition affecting bone is characterised by 'rubber jaw', whereby bone is resorbed and replaced by fibrous tissue? Oesteoporosis Osteomalacia Hypervitaminosis A Secondary nutritional hyperparathyroidism Osteomyelitis Please select an option Incorrect. Here there is a loss of bone quality but the bone is normally mineralised, although pathological fractures may occur. The correct answer is secondary nutritional hyperparathyroidism which is associated with low calcium / high phosphate diets. Although nutritional inbalances are the most common cause of rubber jaw, it can also occur with renal secondary hyperparathyroidism. WikiVet Article: Hyperparathyroidism, Osteoporosis. Incorrect. This condition is due to diets low in phosphorus or vitamin D, there is thickening of the physis and flaring of the metaphysis. The correct answer is secondary nutritional hyperparathyroidism which is associated with low calcium / high phosphate diets. Although nutritional inbalances are the most common cause of rubber jaw, it can also occur with renal secondary hyperparathyroidism. WikiVet Article: Hyperparathyroidism, Osteomalacia. Incorrect. Here there is bone proliferation, it is classically seen in cats on liver diets. The correct answer is secondary nutritional hyperparathyroidism which is associated with low calcium / high phosphate diets.Although nutritional inbalances are the most common cause of rubber jaw, it can also occur with renal secondary hyperparathyroidism. WikiVet Article: Hyperparathyroidism, Hypervitaminosis A. Correct! This condition is seen associated with low calcium / high phosphate diets. Although nutritional inbalances are the most common cause of rubber jaw, it can also occur with renal secondary hyperparathyroidism. WikiVet Article: Hyperparathyroidism Incorrect. Osteomylitis is inflammation of the medullary cavity. Spread of infection and pathological fractures are likely consequences. The correct answer is secondary nutritional hyperparathyroidism which is associated with low calcium / high phosphate diets. Although nutritional inbalances are the most common cause of rubber jaw, it can also occur with renal secondary hyperparathyroidism. WikiVet Article: Hyperparathyroidism, Osteomyelitis.

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What is the most common skeletal neoplasia of dogs and cats? Ossifying fibroma Osteosarcoma Haemangiosarcoma Fibrosarcoma Chondrosarcoma Please select an option Incorrect. Ossifying fibroma is a rare benign neoplasia affecting the heads of horses and cattle. Grossly seen as a sharply demarcated expansive mass which distorts normal bone contour. The correct answer is osteosarcoma (OSA), any malignant neoplasm of mesenchymal origin in which the cells produce osteoid. They typically arise in the medullary cavity and account for 80% of skeletal neoplasia in dogs and cats. WikiVet Article: neoplasia Correct. Osteosarcoma (OSA) is any malignant neoplasm of mesenchymal origin in which the cells produce osteoid. They typically arise in the medullary cavity and account for 80% of skeletal neoplasia in dogs and cats. WikiVet Article: neoplasia Incorrect. Haemangiosarcoma does not directly affect the bone, but it can metastasise to skeletal muscle from other sites. It along with fibrosarcoma accounts for 7% of all skeletal neoplasia of cats and dogs. The correct answer is osteosarcoma (OSA), any malignant neoplasm of mesenchymal origin in which the cells produce osteoid. They typically arise in the medullary cavity and account for 80% of skeletal neoplasia in dogs and cats. WikiVet Article: neoplasia Incorrect. Fibrosarcoma forms from connective tissue of the medullary cavity or periosteum. It along with haemangiosarcoma accounts for 7% of all skeletal neoplasia of cats and dogs. The correct answer is osteosarcoma (OSA), any malignant neoplasm of mesenchymal origin in which the cells produce osteoid. They typically arise in the medullary cavity and account for 80% of skeletal neoplasia in dogs and cats. WikiVet Article: neoplasia Incorrect. Chondrosarcoma is any malignant neoplasm in which mesenchymal cells produce chondroid matrix. It involves development of bone via metaplasia or endochondral ossification, most commonly seen in old dogs and sheep. It accounts for 10% of all skeletal neoplasia in dogs and cats. The correct answer is osteosarcoma (OSA), any malignant neoplasm of mesenchymal origin in which the cells produce osteoid. They typically arise in the medullary cavity and account for 80% of skeletal neoplasia in dogs and cats. WikiVet Article: neoplasia

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What is prognathia? A short maxilla Communication of nasal and oral cavities Mandible longer than maxilla (undershot jaw) Absence of mandibles Absence of part of the lip rostral to the nasal septum Please select an option Incorrect. This is brachygnathia. The correct answer is abnormal prolongation of the maxilla/mandibles, this is a congenital abnormality of the oral cavity. Link to relevant webpage: Malocclusion. [- Pathology#Developmental Pathology|WikiVet Article: Developmental pathology] Incorrect. This describes a cleft palate in which there is inadequate growth of the palantine shelves. Aspiration pneumonia is a common sequele. The correct answer is abnormal prolongation of the maxilla/mandibles, this is a congenital abnormality of the oral cavity. WikiVet Article: Cleft palate. Link to relevant webpage: Malocclusion. Correct. This is a congenital abnormality of the oral cavity. Link to relevant webpage: Malocclusion. Incorrect. This is agnathia which is seen in piglets. The correct answer is abnormal prolongation of the maxilla/mandibles, this is a congenital abnormality of the oral cavity. Link to relevant webpage: Malocclusion. Incorrect. This is a harelip. The correct answer is abnormal prolongation of the maxilla/mandibles, this is a congenital abnormality of the oral cavity. Link to relevant webpage: Malocclusion - Congenital abnormality.

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Chondrodysplasia leads to the development of which abnormality? Disproportionate dwarfism Angular limb deformity Diaphyseal dysplasia Marble bone disease Cervical vertebral stenotic myelopathy Please select an option Correct! Disproportionate dwarfism is due to defective cartilage growth at the physis. In dogs a localised form occurs e.g. affecting skulls of Pekingese and Bulldogs or the limbs of Dachshunds and Bassett hounds. WikiVet Article: Developmental abnormalities Incorrect. Angular limb deformity either, lateral deviation of distal portion of limb (valgus) or medial deviation of distal portion of limb (varus), is most commonly seen in foals. It may be congenital or acquired due to malpositioning in utero, excessive joint laxity, trauma or overnutrition, but there are other causes. The correct answer is disproportionate dwarfism, it is due to defective cartilage growth at the physis. In dogs a localised form occurs e.g. affecting skulls of Pekingese and Bulldogs or the limbs of Dachshunds and Bassett hounds. WikiVet Article: Developmental abnormalities Incorrect. Congenital hyperostosis is a rare, genetic condition of pigs, presenting as diaphyseal dysplasia. There is excessive periosteal intramembranous bone, particularly in long bones, seen clinically as greatly thickened long bones and tense, shiny skin which is closely adherent to tissues below. Affected animals are born dead or die soon after birth. The correct answer is disproportionate dwarfism, it is due to defective cartilage growth at the physis. In dogs a localised form occurs e.g. affecting skulls of Pekingese and Bulldogs or the limbs of Dachshunds and Bassett hounds. WikiVet Article: Developmental abnormalities Incorrect. Osteopetrosis or marble bone disease occurs in sheep, dogs, cattle, horses. It is a failure of resorption by osteoclasts leading to a failure of remodelling of cancellous bone and so the bone becomes thickened and dense but brittle. The correct answer is disproportionate dwarfism, it is due to defective cartilage growth at the physis. In dogs a localised form occurs e.g. affecting skulls of Pekingese and Bulldogs or the limbs of Dachshunds and Bassett hounds. WikiVet Article: Developmental abnormalities Incorrect. Cervical vertebral stenotic myelopathy or 'wobblers' is a conditon seen primarily in equine practice. It is a narrowing of the vertebral canal due to malarticulation or maldevelopment of the vertebrae. Most common in fast growing male thoroughbreds ranging from 8 months to 4 years presenting as hind limb ataxia due to cord compression. It is seen in dogs, and may be inherited in borzois and basset hounds and probably dobermans and great danes. The correct answer is disproportionate dwarfism, it is due to defective cartilage growth at the physis. In dogs a localised form occurs e.g. affecting skulls of Pekingese and Bulldogs or the limbs of Dachshunds and Bassett hounds. WikiVet Article: Developmental abnormalities Link to Merck: Small animal myelopathies

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Swelling in the metaphyses of long bones corresponding with a neutrophilic infiltrate occurs in which skeletal condition? Fibrous dysplasia Hypertrophic osteopathy Hypertrophic osteodystrophy Craniomandibular osteopathy Ectopic mineralisation Please select an option Incorrect. Fibrous dysplasia is a rare condition seen in young horses, dogs and cats. Grossly it is seen as an expansive firm fibro-osseous mass lesion in the metaphyses.The correct answer is hypertrophic osteodystrophy, which occurs in young (usually 3-6 months old), fast growing dogs of large or giant breeds. The distal radius and ulna are most severely affected, the clinical signs observed are fever, anorexia and severe lameness. WikiVet Article: hyperplastic bone disease InCorrect! Hypertrophic osteopathy also called hypertrophic pulmonary osteopathy occurs in all species and it is associated with chronic lesions usually in the thorax. It is seen grossly as periosteal proliferation of bone on diaphyses of distal limbs. It is progressive and bilateral. The correct answer is hypertrophic osteodystrophy, which occurs in young (usually 3-6 months old), fast growing dogs of large or giant breeds. The distal radius and ulna are most severely affected, the clinical signs observed are fever, anorexia and severe lameness. WikiVet Article: hyperplastic bone disease Correct! Hypertrophic osteodystrophy occurs in young (usually 3-6 months old), fast growing dogs of large or giant breeds. The distal radius and ulna are most severely affected, the clinical signs observed are fever, anorexia and severe lameness. WikiVet Article: hyperplastic bone disease Incorrect. Craniomandibular osteopathy is seen mainly in West Highland White Terriers and Scottish Terriers 4-8 months of age. It is seen grossly as bilaterally symmetrical proliferative changes in the mandible, occipital and temporal bones, including the tympanic bullae. The correct answer is hypertrophic osteodystrophy, which occurs in young (usually 3-6 months old), fast growing dogs of large or giant breeds. The distal radius and ulna are most severely affected, the clinical signs observed are fever, anorexia and severe lameness. WikiVet Article: hyperplastic bone disease Incorrect. Ectopic mineralisation, also called heterotopic mineralisation (calcification) is a deposition of calcium phosphate, silicate and other substances in unusual locations.The correct answer is hypertrophic osteodystrophy, which occurs in young (usually 3-6 months old), fast growing dogs of large or giant breeds. The distal radius and ulna are most severely affected, the clinical signs observed are fever, anorexia and severe lameness. WikiVet Article: hyperplastic bone disease