Bone & Muscle Flashcards
What is the basic structure of bone?
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What is the structural unit of compact bone vs. spongy (cancellous) bone?
compact= osteon
Spongy bone= trabeculae
What type of bone formation does not use growth plates?
intramembranous
Describe the process of intramembranous ossification?
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Describe the process of endochondral ossification?
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What are the different zones of the growth plate?
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What are two major requirements for proper fxn of the growth plate?
- need adequate mineralized collagen/cartilage
- need adequate blood vessel quality (need angiogenesis)
Type of Bone?
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woven bone
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Type of Bone?
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lamellar bone
What are the categories used to classify bone fractures?
Location: which bone & where
Transverse/Oblique/Spiral
Open/closed
Complete/Incomplete
Comminution (brocken into fragments)
Displacement (how has the distal end moved relative to the proximal end?)
OLD ACID
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What are the four stages of fracture healing?
- hematoma
- fibrocartilagenous callus
- Bony callus
- Remodeling
What stage of fracture healing is shown?
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What timeframe is this fracture in healing?
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7-10d
granulation tissue and bone necrosis
What timeframe is this fracture healing?
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3 weeks
fibrocartilagenous callus
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What stage of fracture healing is shown?
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bony callus
nearly healed fracture site
Describe the SALTER HARRIS fracture classification scheme?
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DDX?
Breed?
When mostly likely to see it?
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craniomandibular osteopathy
Westies & scotties
3-7 mo (stops 11-13mo)
autosomal recessive
A dog presents with excessive bone fragility that lead to a fracture. Likely DDX?
Osteogenesis imperfecta
On radiographs, there is increased bone density. Likely DDX?
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Osteopetrosis
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DDX?
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Chondrodysplasia
Underlying reason why the bone fractured?
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Osteoporosis
Which is worse? Osteoporosis or osteopenia?
Osteoporosis
osteopenia: decreased numbers of thin trabeculae
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Periarticular hemorrhage. DDX? Which species are susceptible to this condition?
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Scurvy
humans, primates, guinea pigs
A dog presents with a flexible jaw. You determine that there has been alot of fibrous CT layed down instead of bone. What is the likely DDX?
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Fibrous osteodystrophy d/t hyperPTH
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Rickets
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Rickets- Costochondral jxn swellings aka ricketic rosary
What should the vet check for?
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hypertrophic osteopathy
thoracic rads for space occupying mass
You observe bony proliferation w/o lysis on the periosteum. Likely DDX?
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hypertrophic osteopathy
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hypertrophic osteodystrophy
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hypertrophic osteodystrophy
A german shepherd presents w/ shifting limb lameness.
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panosteitis
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A young dog presents for lameness
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panosteitis
A 5 mo old yorkie presents with lameness. DDX?
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Legg-Perthes Disease
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Actinomyces bovis
Lumpy jaw= osteomyelitis
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Where in the bone is osteomyelitis most common and why?
physes
b/c blood vessels makes hair pin turn and leads to bacteria getting stuck in the vessel at the physis
A foal comes in with a fever and depression. Why would this condition be recurrent?
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Likely septicemic E.coli/salmonella osteomyelitis
Sequestrum of necrotic bone surrounded by infection causes recurrent infections
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Salmonella dublin
vertebral osteomyelitis
What is the structure shown seen with osteomyelitis sometimes?
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Sequestrum
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Atrophic rhinitis
Pasteurella multocida and bordetella
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Osteosarcoma
periosteal rxn & thinning of the cortex
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mutilobular tumor of bone
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multiple myeloma
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synovial proliferation
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eburnation
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osteophytes
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inflammatory arthritis
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OCD
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synovial cell sarcoma
A dachshund presents with acute hindlimb paralysis. DDX?
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IVDD
type I
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Ossifying pachymeningitis
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rowing and internalization of nuclei = muscle damage
satellitosis aka rowing of nuclei
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fragmentation of sarcomplasm
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C. botulinum toxin
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Clostridium blackleg
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trichinella
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White muscle disease