Pathology - Test 2 (Bone Pathology)

Front 1

Amelia

Back 1

a congenital disturbance; limb deformity

*absence of a limb

Front 2

Syndactyly

Back 2

a congenital disturbance; limb deformity

*fusion of digits

Front 3

Polydactyly

Back 3

a congenital disturbance; limb deformity

*multiple digits

Front 4

Arthrogryposis

Back 4

a congenital disturbance; limb deformity

* permanent flexure of the limbs

Front 5

a cause of arthrogryposis

Back 5

-from ingestion of lupines at 40-70 days of gestation
-Bluetongue virus
-Manganese deficiency

Front 6

Four limb and digital deformities

Back 6

(1) amelia
(2) syndactyly
(3) polydactyly
(4) arthrogryposis

Front 7

Five spinal deformities

Back 7

(1) kyphosis
(2) lordosis
(3) scoliosis
(4) spina bifida
(5) hemivertebra

Front 8

Kyphosis

Back 8

Spinal deformity (congenital)

*dorsal curvature of the spine

Front 9

Lordosis

Back 9

Spinal deformity (congenital)

* ventral curvature of the spine

Front 10

scoliosis

Back 10

Spinal deformity (congenital)

*lateral curvature of the spine

Front 11

Spina bifida

Back 11

Spinal deformity (congenital)

*failure of the neural arch to close, leaving an exposed spinal cord or meninges

Front 12

Hemivertebra

Back 12

Spinal deformity (congenital)

*a failure of fusion in the fetal spine producing a small vertebra (short vertebral bodies)

Front 13

Osteodystrophy

what is it and give three examples

Back 13

-abnormal growth of bone (rare)

(1) Periosteal Hyperostosis
(2) Osteogenesis imperfecta
(3) Osteopetrosis

Front 14

Periosteal Hyperostosis

Back 14

-osteodystrophy (congenital)

*proliferation of periosteal new bone on long bones
-inherited of pigs and animals stillborn

Front 15

Osteogenesis Imperfecta

Back 15

-osteodystrophy (congenital)

*defect in osteoblasts therefore defective osteoid formatio; cortex is thin and trabeculae are decreased in number
-rare, inherited disease of cattle

Front 16

Osteopetrosis

Back 16

-osteodystrophy (congenital)

*osteoclast defect therefore bone is thick, but brittle and prone to fracture
-inherited of lambs and calves (stillborn)

Front 17

Chondrodystrophy

Back 17

-congenital

*defect in the cartilage of the bones formed by endochondrial ossification; bones are short with normal width and premature closure of the growth plate

Front 18

What do animal's bones with chondrodystrophy look like?

Back 18

short, but normal width with premature closure of growth plates; normal histologically

Front 19

What breeds is chondrodystrophy normal in?

Back 19

-bull dog and pekingese

Front 20

Hemorrhage

Back 20

occurs when bone is damaged by any cause such as fracture, osteomyelitis, of neoplasia (trauma primarily)

Front 21

Ischemia

Back 21

common with bone fractures, neoplasia or inflammation and leads to necrosis

(aseptic necrosis of the femoral head in miniature dog breeds)

Front 22

Hypertrophic osteopathy

Back 22

-a circulatory disturbance

-periosteal proliferation of bone along the diaphysis of limb bones that is symmetrical
-rare and mostly in the dog
-increased vascular perfusion to the periosteum

Front 23

This will often cause regression of bone formation in the case of hypertrophic osteopathy

Back 23

vagotomy

Front 24

Osteochondrosis

Back 24

-metabolic bone disease

*characterized by a defect in endochondrial ossification, leading to a focal area of cartilage that is thickend

Front 25

Gross Lesions of osteochondrosis

Back 25

-a focal area of cartilage that is thickend and projects into the metaphysis and epiphysis
-articular cartilage areas are weaker and under more stress so they may collapse and produce fissures - with flaps of cartilage breaking off and forming bone cysts

Front 26

osteochondrosis dissecans

Back 26

-a result of osteochondrosis
-articular cartilage areas are weaker and under more stress so they may collapse and produce fissures - with flaps of cartilage breaking off and forming SUBCHONDRAL bone cysts

Front 27

Where osteochondrosis normally manifests itself.

Back 27

in joint

Front 28

Certain bones are more commonly affected in certain animals - where are they affected in the:
*dog
*tibia
*pigs

Back 28

*dog=proximal humerus
*horse=distal tibia
*pigs=distal femur and distal humerus

Front 29

Osteochondrosis Microscopically

Back 29

blood vessels fail to grow into the hypertrophic zone of cartilage and zone persists as a focal, thickened area that does not mineralize

Front 30

Tibial dyschondroplasia in birds

Back 30

-similar to osteochondrosis in mammals, but affects young domestic poultry
-proximal tibia has anterolateral bowing due to mass of retained cartilage

Front 31

Osteoporosis

Back 31

-a lesion, not a specific disease
-holes in the bone (total amount of bone is decreased, but it in normal)
-either an increased rate of reabsorption in the bone or a decreased rate of formation
-synonymous with osteopenia
-many causes

Front 32

Bones most commonly affected by osteoporosis.

Back 32

-bones with large amounts of spongy or cancellous material

-vertebra, scapula, ilium, metaphysis of long bones

Front 33

Gross lesions of osteoporosis.

Back 33

-bones are of normal diameter and have smooth surfaces, but they are brittle and the cortex, esp near the metaphysis is thinned
-cancellous bone compresses easily

Front 34

Microscopic lesions of osteoporosis.

Back 34

-bone trabeculae are decreased in number and growth plates are closed or narrow

Front 35

Four types of osteoporosis

Back 35

(1) Nutritional osteoporosis
(2) Disuse osteoporosis
(3) senile osteoporosis
(4) corticosteroid-induced osteoporosis

Front 36

Most common type of osteoporosis

Back 36

nutritional - causes may include starvation, protein deficiency and deficiencies in copper, mag, zinc (not enough Ca)

Front 37

Osteomalacia and Rickets

Back 37

-softening of bone caused by inadequate mineralization

Front 38

Difference between Osteomalacia and Rickets

Back 38

Osteomalacia- adult form
Rickets-young, growing animals

Front 39

Most common species for ostoemalacia/rickets

Back 39

exotics and chickens

ricketts - New world monkeys and chickens are susceptible because they can not utilize dietary sources of vitamin D (can't activate in the skin)

Front 40

differences between osteochondrosis and osteomalacia

Back 40

Osteochondrosis - bone does not form corectly, but mineralizes properly

Osteomalacia-bone forms correctly, but does not mineralize properly

Both have similar, thick cartilage

Front 41

Gross lesions of osteomalacia

Back 41

soft, not brittle, and may bend and fracture easily; deformities occur in response to normal weight bearing; cortices are thin and cancellous bone is soft

Front 42

cause of osteomalacia

Back 42

-deficiency of vitamin D (includes intestinal malabsorption, inadequate sunlight, or secondary to chronic renal disease-failure to activate vitamin D)
-phosophorous
-or both

Front 43

What does rickets affect?

Back 43

-the growth plates - they are long and irregular in width
-metaphysis is widened and collapses under weight bearing producing a mushroom shape (enlargement is most obvious at the chosochondral junction)

Front 44

When vitamin D deficiency is the cause of osteomalacia, what also develops?

Back 44

-hypocalcemia develops which causes hyperparathyroidism

Front 45

Fibrous osteodystrophy.

Back 45

excessive resorption of bone, followed by replacement with fibrous, connective tissue and some metaplastic bone
-rubber jaw

Front 46

cause of fibrous osteodystrophy.

Back 46

hyperparathyroidism
primary - neoplasm
secondary - nutritional or renal (most common)

Front 47

cause of nutritional hyperparathyroidism

Back 47

imbalance of Ca and P (often high P caused by animals on all meat diet)

Front 48

cause of renal hyperparathyroidism

Back 48

P is not excreted due to renal disease

Front 49

gross signs of fibrous osteodystrophy

Back 49

-bone is soft and bends easily (rubber jaw)
-head is usually affected first, then axial skeleton
-in horses, excessive amounts of fibrous tissue are produced resulting in big head

Front 50

scurvy

Back 50

vitamin C deficiency (a cofactor in the cross-linking of collagen); this leads to inadequate osteoid formation (fewer and thinner spicules); mineralization is normal (therefore normal epiphysis)

Front 51

animals affected by scurvy

Back 51

primates and guinea pigs - can't synthesize vitamin C

Front 52

gross lesion of scurvy

Back 52

hemorrhage is the characteristic lesion

Front 53

flurosis

Back 53

occurs with chronic ingestion of fluroide (may resemble rickets)

Front 54

gross lesion of flurosis

Back 54

periosteal new bone formation affecting the distal limbs

Front 55

hypervitaminosis A in cats

Back 55

multiple extostosies (bone on top of bone) occurring principally in the cervical vertebra, also on sternebra and joints of the long bones; result of toxic change by viatmin A in chondrocytes

Front 56

What is Vit A toxic to?

Back 56

chondrocytes

Front 57

Avian Perosis

Back 57

disease of young, growing poultry and game birds characterized by swollen, enlarged hocks and twisting deformities of the distal tibia and proximal metatarsus
-gastrocnemius tendon often slips out of condyle and birds cant' walk

Front 58

Osteomyelitis

Back 58

inflammation of bone and bone marrow, most often caused by bacteria (secondly fungi)

Front 59

What does most osteomyelitis result in ?

Back 59

bone reabsorption (lysis) with formation of cavities in the bone that fill with inflammatory exudate; necrotic bone is normally reabsorbed, but sometimes forms a sequestrum

Front 60

sequestrum

Back 60

-a result o osteomyelitis

-formed when the necrotic bone is not reabsorbed, leaving a fragment of bone that is without blood supply and can't be phagocytized

Front 61

other than bone reabsorption, what is another result of an animal getting ostomyelitis?

Back 61

bone proliferation (esp. if the periosteum is involved)
-can be extensive (actinomyces - Lumpy Jaw), and the deep mycoses (histoplasma, blastomyces)

Front 62

most common source of osteomyelitis

Back 62

direct extension from an arthritis or an inflammatory process overylying bone such as sinusitis or periodontitis

Front 63

other causes of osteomyelitis (other than direct extension)

Back 63

-direct trauma
-hematogenous spread (young animals due to the highly vascular arease in the metaphysis of growing bones); vertebra are favorite sites for this

Front 64

Hypertrophic osteodystrophy.

Back 64

characterized by a sudden onset of fever with painful swellings of the metaphysis of long bones

Front 65

breeds prediposed to hypertrophic osteodystrophy

Back 65

young large and giant breed dogs

Front 66

principle lesion of hypertrophic osteodystrophy

Back 66

-principle lesions occur at distal metaphysis of long bones
-periosteal new bone formation which is edematous
-cartilage and bone form external to this and associated with hemorrhage

Front 67

Panosteitis

Back 67

-self-limiting disease (regresses in several months)
-endosteal new bone formation in the diaphysis filling the medullary cavity
-NO inflammation

Front 68

who does panosteitis affect?

Back 68

young, large and giant breed dgos affecting the long bones
-males affected 4:1 over females

Front 69

craniomandibular osteopathy

Back 69

a bilateral, irregular, osseous proliferation of the mandible, tympanic bullae and sometimes the bones of the head and limbs

Front 70

who does craniomandibular osteopathy normally affect?

Back 70

terrier breeds and animals under 1 year

Front 71

why is craniomandibular osteopathy important for animals if it regresses in a few weeks?

Back 71

-periosteal new bone formation in the mandible and tympanic bullae can interfere with mastication because TM joints are thickened and hard to move
-inflammation and fever is usally present

Front 72

Pathologic fracture

Back 72

fracture occurring secondary to a bone disease like neoplasia, osteomyelitis or nutritional bone disease

Front 73

comminuted fracture

Back 73

fracture with multiple small fragments of bone

Front 74

greenstick fracture

Back 74

fracture with one side of the bone being broken while the other side is bent without separation of the bone

Front 75

pseudoarthrosis

Back 75

a false joint; the ends of the fractured bones become smooth and encircled by a fibrous capsule in which the bone moves

Front 76

factors which affect the repair process of a fracture

Back 76

(1) blood supply
(2) amount of movement at the fracture site
(3) gap at the fracture site
(4) presence of necrotic bone
(5) presence of infection
(6) presence of muscle or other tissue fragments

Front 77

non-union

Back 77

a failure of a fracture to heal leaving the bone ununited

Front 78

process of bone repair following a fracture

Back 78

-following a fracture, a blood clot forms at the site
-this is replaced by fibrous tissue, woven bone and cartilage to form a unorganized meshwork = AKA a callus
-the primary callus is remodeled over time to form a secondary callus of mature bone

Front 79

osteoma

Back 79

benign tumor of bone, rare
-occur in head of cattle and horses

Front 80

gross lesions of osteoma and implications

Back 80

tumors can be 15 cm and can cause problems with mastication and respiration
-composed of trabecular bone covered by a fibrous capsule

Front 81

chondroma

Back 81

benign tumor of cartilage, rare
-flat bones of sheep, dogs and cats
-made of mature, hyaline cartilage

Front 82

osteochondroma

Back 82

bone and cartilage benign tumor
-affect long and flat bones

Front 83

where do most osteochondromas arise

Back 83

the surface of bones at the growth plate

Front 84

species affected by osteochondroma

Back 84

-inherited in dogs and horses (animals affected just after birth and ceases with closure of growth plate)

-mature cats associated with retrovirus (mainly on flat bones)

Front 85

Multilobular tumor

Back 85

-most common benign bone tumor
-occurs in the bones of the skull of the dog
-tumor is slow growing and progressively malignant with metastasis occuring late in the disease
-can cause compression of the brain or expansion into the orbit or sinuses making resection difficult

Front 86

osteosarcoma

Back 86

-MOST common bone tumor of animals and affects large and giant breed dogs and cats
-tumor of malignant osteoblasts
-mast malignant and aggressive

Front 87

where do osteosarcomas arrise?

Back 87

-within the medullary cavity of the metaphysis of long bones
-most common sites in dogs: prox. humerus, distal radius, both ends of femur and tibia
-cats most common sites: equally in flat and long bones

Front 88

gross lesion of osteosarcoma

Back 88

-very destructive of bone, causing extensive hemorrhage, necrosis, bone lysis and periosteal proliferation
-pathologic fractures can occur
-usually does not cross the joint space

Front 89

telangiectatic osteosarcoma

Back 89

osteosarcoma with tumors that have blood-filled spaces

Front 90

compound osteosarcoma

Back 90

osteosarcoma where cartilage is also formed (in addition to bone)

Front 91

chondrosarcoma

Back 91

second most common bone tumor of the dog
-affects large, but NOT giant breed dogs and occurs in cats and sheep
-in flat bones and nasal cavity, but also in long bones

Front 92

difference between osteosarcoma and chondrosarcoma

Back 92

chondrosarcoma is:
-slower growing
-causes less destructive lesions with less lysis and more proliferation of bone
-will cross the joint space
-slower to metastasize