Pathology of Bone - Part 1 Flashcards
In addition to provide ______ support and
protecting key _____ from traumatic injury bone
plays an important role in ___ homeostasis
mechanical, organs, Ca
Bones are dynamic organs undergoing _______ _____ throughout life
constant remodeling
Bones are always working and have a great capability to repair. Play a significant role in Calcium metabolism.
Diseases of bone are quite important in Veterinary
Medicine and may result in significant ________ _______.
economic loss
Diseases of bone are often ______-_____.
under-diagnosed
b/c post-mortem pathologists usually don’t check bone; so if information about bone issues is not provided, pathologists won’t check.
Knowledge of the _____ and ______ anatomy of bone, the factors that regulate bone _____ and _____ and an understanding of the responses to _____ are key to an appreciation of the pathogenesis and pathology of bone diseases
gross, microscopic, formation, resorption, injury
Recognizing where the Epiphysis, diaphysis of the bone is important. Spongey, etc.
The physis contains ?
cartilage
Compact bone
Osteons;dense
Outside bone there is a layer of CT called the ________. Cells transform into bone producing cells. Cortical bone
periosteum
Most bones arise from _______ ossification.
endochondrial
Few bones, such as bones on top of head, arise from __________ ______.
intramembranous ossification
Chondrodysplasia/ Chondrodystrophy (Chondrodysplasia fetalis or ________ _____) is _____-associated, usually _______ conditions that occur in ____, _____ and ____. _______ ______ growth is normal but _______ growth of ______ is abnormal resulting in ______ closure of _____ _____ and decrease ____ of ____ bones (affects bones that form by ________ _______).
disproportionate dwarfism, Breed, hereditary, dogs, cattle, sheep, Membranous appositional, interstitial, cartilage, premature, growth plates, length, long, endochondral, ossification
essentially skeletal dysplasia; rapid maturation of bones that arise from endochondral ossification, leading to premature closing of growth plates.
Chondrodysplasia/ Chondrodystrophy (Chondrodysplasia fetalis or disproportionate dwarfism) is most common in beef breeds (____,_____).
Angus, Hereford
Abnormal development of all bones that arise from endochondral ossification.
In Dexter cattle, ________ animals for the Dexter phenotype (Dexter “_______ type” dwarfism) are
severely ______ and are usually aborted before __ _____ of gestation (this is the most severe form of bovine _______).
What is the basis of this condition?
homozygote, bulldog, deformed, 7 months, chondrodysplasia
Basis of this condition is the premature closure of growth plates.
“Dexter bulldog” is _______ lethal _______.
Congenital, Chondrodysplasia
Dexter bulldog is an ______ condition of _____ cattle.
Affected calves are often _____ and exhibit
________ dwarfism, short ______ ______, marked ______ (shortening of the limbs), ____ head with short _____, protruding _____ and large abdominal ______
inherited, Dexter, aborted, disproportionate, vertebral column, micromelia, large, muzzle, tongue, hernia
The lethal bulldog syndrome is also
reported occasionally in ______ and ____
Breeds of cattle
Holstein, other
Dexter bulldog
Shortening of bones in the body
Vertebral column isvery short
mandible is very small, so tongue appears to be very big.
Chondrodystrophic dog breeds exhibit _______
chondrodysplasias involving _______ bones.
localized, specific
Basset Hound
Chrondrodysplasias
Micromelic achondroplasia
Melic = limbs
achondroplasia = abnormality in development of cartilage
Pug
Chondrodysplasias
Brachicephalic achondroplasia
Exercise intolerance,
In addition to the pug, other brachiocephalic chondrodystrophic dog breeds are ______ and _____ (________ ________).
Bulldogs, Boxers, brachycephalic achondroplasia
Cervico-Vertebral Stenotic Myelopathy is also called?
Wobbler’s syndrome
Stenosis = narrowing of a channel
myelopathy = degeneration of spinal chord
Localized skeletal dysplasia is most common in _____ and _____ breed dogs (mainly _____ _____ and _______ ______).
horses, large, Great Danes, Doberman Pinschers
Localized skeletal dysplasia can also be classified as a __________ _____ disease which affects the _____ skeleton.
degenerative joint, axial
Wobbler’s syndrome results in _____ or _____
compression of the _____ spinal cord (SC) by _____ cervical vertebrae.
dynamic, static, cervical, abnormal
In the dynamic form of Wobbler’s syndrome, spinal chord _______ occurs when the _____ is flexed; in the static form, spinal chord ______
occurs no matter what position the _____ is in.
compression, neck, compression, neck
Cervical Vertebral Stenotic Myelopathy –Doberman
Atlantic Veterinary College – pathologists look for “Ski-slope lesion” –> compression of spinal chord –> ascular changes, ischemia, necrosis.
Dynamic condition= clinical signs more prominent if neck is flexed
Abnormal developemtn of cervical vertebrae –> compression and narrowing of spinal canal.
Wobbler Syndrome, horse
Severe compression
Horse, Wobbler syndrome
ski slop change in vertebrae
Osteopetrosis is an _______ disease (autosomal _______ trait) caused by lack of _______ or by
_________ failure to reabsorb the ______ ______. Results in ________ bone ______
and lack of medullary (bone marrow) ______.
inherited, recessive, osteoclasts, osteoclast, primary
spongiosa, increased, density, spaces
can not ? cancerous bone
no medullary cavity in the bone
if section long bone in middle, should see medullary cavity in bone; this cavity is where hematopoiesis will occur. b/c of this disease, you willl have no reabsorption of trabecular ?bone and no cavity present.
aplastica anemia due to lack of bone
Petros means?
rock
Osteopetrosis is also known as?
Metaphyseal Dysplasia
Osteopetrosis/Metaphyseal Dysplasia results in _______ _______ ( aka? _____ ______ _____). Most affected animals are ______.
diffuse osteosclerosis, ↑ bone density, stillborn
In cases of Osteopetrosis, since there is ___ ____ for the hematopoietic tissues of the bone marrow to grow, individuals that survive often present _____ _____ and have a susceptibility to bone ______.
Reported mainly in _____, _____, _____ and ______.
no space, aplastic anemia, fractures, dogs, sheep, cattle, horses
Osteopetrosis in a cat
Congenital cortical hyperostosis of pigs is an
Autosomal _________ ______ condition in pigs.
recessive, inherited
In a case of congenital cortical hyperostosis of pigs, the limbs (primarily the ______) appear ______
due to _______ deposition of _______ ________ on the ________ surface
(________ bone), and blockage of the local _______ circulation.
forelimbs, swollen, excessive, radiating
trabeculae, periosteal, extracortical, lymphatic
usually affects one or more limbs.
deposition of bone outside the periosteum
changes in drainage of lymph
can develop hyperglycemia
Most pigs diagnosed with congenital cortical hyperostosis are born?
Dead or die within hours
Congenital cortical hyperostosis of pigs has been compared to ________ disease (aka? ) observed in children and young monkeys.
Caffey’s, infantile cortical hyperostosis,
Congenital cortical hyperostosis of
pigs
Diffusely thickened
Congenital cortical hyperostosis of
pigs
What can be seen here?
Congenital cortical hyperostosis of
pigs
bone production outside periosteium can be seen here
What can be seen here?
Congenital cortical hyperostosis of
pigs
Bone production on the periosteal surface
Amelia is defined as the absence of a ________.
limb(s|)
Hemimelia is defined as the absence of the _____ _____ of a limb
distal half
Polymelia: _________ limbs
Supernumerary
Phocomelia: (phoco: “_____”) Severe ________ of the ____ bones of the limbs. In humans was associated with the use of _______ (a sedative drug) during ______ (____ and/or ____ close to the trunk –resembling “____ _____”) –> world-wide tragedy in the ___ & early ___
seal, shortening, long, thalidomide, pregnancy, feet, hands, seal flippers, 50’s, 60’s
Micromelia is defined as abnormally ____ or ____ limb(s
small, short
Syndactyly is defined as the fusion of the _____
digits
Polydactyly is defined as ______ digits
supernumerary
Lordosis: _______ deviation of the vertebral column
Ventral
Kyphosis: ______ deviation of the vertebral column
Dorsal
Scoliosis: _______ deviation of the vertebral column
Lateral
1 in 100 people may have scoliosis without even knowing. May feel back pain when you are sitting for a long period of time.
Kyphoscoliosis: _____-______ deviation of the vertebral column
Dorso-lateral
Malformations are usually associated with malformed vertebrae. Triangular vertebrae or hemivertebrae.
Calf, Kyphosis
Dorsal deviation of the vertebrae
Born with this condition; during development, because you have a malformed vertebrae, those changes may become more prominent and then you may have compression of spinal chord and clinical signs associated with that.
31 year-old gelding
In thin body condition (395 kg). Loosing weight.
In addition to swayback (lordosis) this horse had
severe degenerative joint disease (degenerative changes in vertebral disc) –> ataxia, proprioceptive deficists
Not uncommon in older people/ animals.
this is an example of acquired loordosis, not congenital
L1 hemivertebra causing congenital scoliosis
Lateral deviation of vertebral column associated with presence of hemivertebra. Triangular shaped vertebra that results in this abnormality.
Angular limb deformities – Relatively common in ______ animals and specially important in _____.
young, horses
More significant in horses because can produce malformation in shape of limbs called valgus deformity.
In many, but not all, cases of angular limb deformities, the origin of the deformity can be traced to an _______ _____ in an ______ ______ _____.
asymmetric lesion, active growth plate
Angular limb deformities are characterized by ________ of the bone: _______ (outward) deviation: ______ deformity, or _____ (inward) deviation: _____ deformity of ____ or ____
limbs distal to the affected _____ ____ or ____.
twisting, lateral, valgus, medial, varus, one, more, growth plate, joint
lateral or inward deviation of distal limbs.
Angular limb deformities may be present at _____ or develop _____ on in life.
birth, later
Caused by trauma after birth of the growth plate –> abnormal development of bone
What are some possible causes of angular limb deformities?
- Malposition in utero
- Joint laxity
- Hypothyroidism (congenital goiter)
- Trauma (ischemia or reduced blood supply)
- Malnutrition
- Impaired endochondral ossification
Carpal Valgus, foal
Lateral
Carpal varus, foal,
Inward deviation of distal limbs
These changes can also be present in people. Primarily important in horses.
Metabolic bone diseases are also referred to as ?
osteodystrophies
Metabolic bone diseases result from disturbed bone _____, ______ or ______ due to either ______ or _______ imbalance
growth, modeling, remodeling, nutritional, hormonal
MBD is characterized by failure of production of
_____ _____, its _________ or its ________.
bone matrix, mineralization, maintenance
MBD Etiology - Nutritional
Vitamins C, D, Ca, P, Protein
deficiencies
MBD Etiology - Hormonal
Parathyroid (PTH), gonads (estrogens),
adrenal problems (corticosteroids).
hyperparathyroid; excessive production of PTH –> increass absorption of calcium in the bone –> abnormalities in bone matrix –? MBD
Chronic use of corticosteroids –> develop MBD specifically osteoperosis
If become too inactive –> MBD or osteoperosis b/c of inactivity.
MBD Etiology - Disuse
Physical inactivity
MBD Etiology - Toxic
Lead and fluoride poisoning, hypervitaminosis
A etc. in high doses –> MBD
In a particular individual metabolic bone diseases can have ______ than one etiology. In addition, _______ forms of metabolic bone disease (_______) can _____ in the same individual.
more, different, osteodystrophies, coexist
In ________ animals metabolic bone disease caused by nutritional deficiency is often caused by deficiency of _____ than ____ nutrient.
domestic, more, one
Metabolic bone diseases are traditionally classified as _______, ________, _________, and ______ ________.
osteoporosis, rickets, osteomalacia, and fibrous
osteodystrophy.
Osteoporosis is characterized by _______ (____ in the amount of bone tissue). There is a _______ amount of bone but the bone that is present is _______.
osteopenia, ↓, ↓, normal
In cases of osteoporosis, grossly there is a
reduction in the ________ of the ______ bone and
a ____ ______ of _______ in the _______ bone.
thickness, cortical, ↓, number, trabeculae, cancellous
In cases of osteoperosis, increase in cortical bone increases susceptibility to pathological fracture.
Osteoporosis Etiology - Nutritional
(3)
Starvation, Cu deficiency, Vitamin C deficiency
Osteoporosis - Aging
In humans peak bone mass occurs around the age of ___; there after _______ outpaces bone ______.
30, resorption, formation
Menopausal women –> decreased estrogen levels –> stimulates bone reabsorption and less bone production
Osteoporosis Etiology - Disuse
??
With age we start to lose height.
Decreased amount of cancellous bone. Bone appears porous. Micro-fractures in vertebrae. With age, we lose fluid so intervertebral discs become thinner. All of this can lead to loss in height, changes in shape of vertebral column
Goat, osteoporosis/ osteopenia – Cornell files
Serous atrophy of bone marrow -Starvation
Sagittal section of the femur. Cortical bone is relatively thin to normal. Medullary cavity appears to be bigger; usually see medullary cavity in the diaphysis, but it goes to the epiphysis here. Know this is a starving animal b/c bone marrow in an adult contains fat so you should see yellow. In here, the bone marrow appears to be translucent.
When we see osteoporosis in animals it is associated with malnutrition and starvation in most cases. Old animals will have osteoporosis to some degree.
Sheep
Osteopenia/ osteoporosis
Mascerated bone of an animal with severe osteoperosis. Cortical bone is very thin. Significant loss of trabecular bone in the metaphysis, so the cavity appears to be very big. Also, you can see porosity within the cortical bone.
Rickets is a _______ bone disease of a complex etiology affecting _______,________ animals
metabolic, young growing
The basic pathogenesis of this disease involves defective _______ of ______ and defective
________ _______ (abnormal _______ of cartilage matrix).
calcification, osteoid, endochondral ossification, mineralization
Etiology of rickets is ________ but typically involves vitamin __ or _______ deficiency
multifactorial, D, phosphorous
In cases of rickets, exposure to _______ (_____ ______ ______ is also important).
sunlight, solar ultraviolet radiation
Cartilage, proliferative layer, hypertrophic layer; cartilage matrix starts to get mineralized and ossified as we move closer to metaphysis.
in case of rickets, there is a normal mineralization of cartilaginous matrix so it does not get mineralized properly –> defect in ossification of the metaphysis. Cartilage continues growing into metaphysis, so the physis are usually bigger and thicker in animals with rickets.
In cases of rickets, there is an irregular thickening of ______ _____ with tongues of ________ cartilage extending into the _______.
growth plates, uncalcified, metaphysis
In cases of rickets, there is a ________ of growth plates –> _______ ends of _____ bones;
enlargement of _________ junctions (“ ______ rosary”); _____-bearing long bones may become ______.
widening, enlarged, long, costochondral, rachitic, weight, bowed
In cases of rickets, hemorrhages beneath the _______ cartilage or in _____ _____
articular, growth plates
In cases of rickets, pathological ______ may occur.
fractures
In cases of rickets, at necropsy ribs _____ rather than ____.
bend, snap
History of Rickets
First described in ______ around 1650 – soft ____
It spread to Europe with the ______ _____.
First “____ pollution disease”. Smog-filled cities deprived children of _________.
England, coal, Industrial Revolution, air, sunlight
Narrow streets prevented sunlight from reaching.
Rickets
Lack/late of mineralization of cartilage in the growth plates –> bones are softer –> twisted
Lack of Vitamin D plays a significant role.
As many as one in four UK children could be lacking in vitamin D, which aids calcium absorption, due to them getting less outdoor activity, widespread use of sunscreen and a fall in the intake of cod
liver oil – a standard supplement used 50 years ago”. “The rise in breast-feeding is also a factor, as breast milk is low in the vitamin, as is the rise in immigrants from hotter climes because darker skin
needs more sun to make enough vitamin D”
Excessive amounts of sunscreen presents action of UV light and synthesis of vitamin D in the skin.
Increased number of immigrants with darker skin don’t have a lot of sunlight, melanin is protective, so if you are born in places closer to the equator with a lot of sun, more melanin produced.
Rickets. Dog from India (varus deformity),
Bowing of the legs.
Weight bearing in softer bones produces lesions in the leg.
Rachitic rosary -foal
Costochondral joints are more prominent.
Usual bump between ribs and cartilage, but in cases of rickets this bump becomes more prominent. Important in diagnosis. If you try to break the ribs, you have to bend the ribs before they snap and break. This is another way you know that the patient has rickets.
Osteodystrophic (growth-arrest)
lines –Rickets-Foal
Also, if you section the costochondral junction, you will see there is more cartilage and thickening of the physis. In some cases, you may see growth arrest lines if the rickets and been associated with periods of malnutrition or starvation. These lines is when there is basically no more production of cartilage for a bit, increased density of the bone, so you may end up with the growth arrest lines.
Chicken: Rachitic rosary
Costochondral junction is very prominent.
Osteomalacia is a disease of grown (_____) animals (______ growth plates).
adult, closed
Osteomalacia has a similar pathogenesis to _____: failure in the mineralization of _____ primarily due to vitamin ___ or ____ deficiency.
rickets, osteoid, D, P
Unmineralized osteoid is resistant to ______ ______ and ______ in the bone.
osteoclastic resorption, accumulates
Defective mineralization, so bones are softer than normal.
Animals affected by Osteomalacia may exhibit bone _____ (______ lameness), pathologic _______ and deformities such as _____, ______ and ______.
pain, shifting, fractures, kyphosis, lordosis, scoliosis
In cases of osteomalacia, collapse of _____ _____ may occur
articular surfaces
over the subchondral bone. Articular surface may look a bit misshapen.
Fibrous Osteodystrophy is also called?
osteodystrophia fibrosa; osteitis fibrosa cystica
Fibrous Osteodystrophy is a relatively common metabolic bone disease characterized by extensive bone ______ and ______ by ______ ______ tissue and poorly ______ _____ bone
resorption, replacement, fibrous, connective, mineralized immature
Fibrous Osteodystrophy is the result of ?
persistent elevations of plasma PTH levels (hyperparathyroidism). PTH main function = increased bone resorption. Acitvates osteoclasts which eats away bone to release calium in blood to increase ca blood levels –> hypercalcemia.
Fibrous Osteodystrophy is more common in?
Can also be seen in?
horses, pigs, dogs and cats
reptiles and New World Monkeys.
What is the basic mechanism of Fibrous Osteodystrophy?
↓Ca; ↑P= ↑PTH
Fibrous Osteodystrophy is due to ?
primary or secondary hyperparathyroidism
If an individual had normal levels of Ca but increased levels of phosphorus would result in the same? b/c in the blood, Ca and phosphorus has a similar ratio that cahnges between species but must be maintained. if p increaes too much even if ca is normal, you have stimulation of pth secretion.
Primary Hyperparathyroidism is usually associated with _______ _______ _______ in dogs
functional parathyroid adenomas
Animals affected by Primary Hyperparathyroidism exhibit marked ________ and ________.
hypercalcemia, hypophosphatemia
In cases of Primary Hyperparathyroidism, Lesions may include ?
FO; Thyroid C-cell hyperplasia; hypercalcemic nephropathy (nephrocalcinosis) and metastatic
mineralization of soft tissues.
calcitonin produced by thyropid cells which decreaes calcium levels (thyroid cell hyperplasia). This is a compensatory mechanism.
calcification –> deposits in normal tissues –> mineralization of soft tissues
calcium deposition in kidneys –> nephrocalcinosis
Nutritional Secondary Hyperparathyroidism is a dietary deficiency of ___; excess dietary
___, or deficiency of Vitamin ______.
Ca, P, D
In most cases nutritional secondary hyperparathyroidism is the result of ___ or ___
in the diet and, with the exception of horses, affects
____ _____ animals.
↓Ca, ↑ P, young growing
“Bran disease”, “Big head”
Nutritional parathydroidism is usually associated with more bran or grain. Bran has elevated p levels –> stimulates PTH production
Bran is a by-product of grain (shell of grain).
Bones in maxillary and mandible are affected. Resorption and replacement of bone with fibrous CT. Sometimes these changes can be subtle.
Fibrous osteodystrophy, Horse. Loss of bone
and replacement by fibrous connective tissue.
tissue is going to be firm. Can not see maxillary sinuses here.
Abnormalities of teeth –> loss of teeth
Secondary Hyperparathyroidism - Renal
Complex etiology but P retention due to loss of
glomerular function and the inadequate synthesis of 1, 25 Dihydroxyvitamin D (1,25, dihydroxy cholecalciferol, calcitriol) by the kidney plays a mayor role.
Kidney is important for active form of vitamin D. An individual with severe chronic kidney disease will have decreased vitamin d level –> decreased calcium absorption in the cat –> hypocalcemia of PTH –> fibrohistodystrophy
Renal osteodystrophy occurs more commonly in the _____. Bones, especially those of the ____ become _____ and are ____ rather than ____, ____ and _____ are usually affected. The mandibles may become quite _____ (“_____ jaw”). Teeth are
often ____ and ______ within the swollen gums and alveolar bone.
dog, head, swollen, firm, hard, maxilla, mandible, pliable, rubber, mobile, malpositioned
Rubber jaw” – Renal
Osteodystrophy, dog
Rubber jaw” – Renal
Osteodystrophy, dog
Rubber jaw” – Renal
Osteodystrophy, dog
Fibrous osteodystrophy
Renal osteodystrophy
Fibrous Osteodystrophy is the result of persistent elevations of _______ ____ levels (?)
plasma PTH, hyperparathyroidism
