Bone Edited (AH/LS) Flashcards
Edited in ref. to Muzzy's review and class notes. Reformatted to make more sense.
Other names for Osteopetrosis
aka: Metaphyseal dyslasia, Marble bone dz.
Spp. associated with Osteopetrosis?
Angus cattle = inherited
Pathogenesis of Osteopetrosis?
Failure of osteoclasts to resorb the primary spongiosa –> accumulation of bony spicules in marrow spaces.**This can lead to Aplastic anemia ** TQ
Other name for Congenital Cortical Hyperostosis?
Diaphyseal dysplasia
Spp. associated with Congenital Cortical Hyperostosis?
Inherited in pigs
Patho of Congenital Cortical Hyperostosis?
Periosteal bone formation on long bones. Deposition on radiating trebeculae –> increase in diameter.
What other condition is associated with Congenital Cortical Hyperostosis?
Edema due to blockage of lymph
Other names for Craniomandiblar Osteopathy?
Scottie jaw, lion jaw, westie jaw.
Spp. associated with CMO?
Inheritied in west highland white terriers = dogs Usually appears @ 4-7 mo of age and regresses.
Path of CMO?
Abnormal periosteal bone formation, irregular resorption –> irregular thickening of mandible/occipital/temporal bones. Tympanic bullae often severely affected.*
Where is the primary lesion of Chondrodystrophy?
1* lesion in growth cartilage –> disproportionate dwarfism = short legs w/ normal-sized heads
Types of Disproportionate Dwarfism?
Dexter type –> bulldog calves Telemark type.
Short headed type.
Pathogenesis of Osteochondrosis?
Failure / delay of endochondral ossification of osteoid (bone matrix) = cartilage retention –> increase in cartilage width.
Etiology of Osteochondrosis?
- Cu deficiencies induced by excess dietary Zn
- Increased Ca2+ intake
- Infarcts
- Idiopathic
(it can be 2* to anything that interferes with vascular invasion of cartilage. (infarct))
Lesions of Osteochondrosis?
Multifocal and Focal
- Dyplasia = wedge shaped hyaline cartilage.
- Mineral debris and Hemorrhage at epiphysis
Are lesions of Osteocondritis dessecans (OCD) focal or multifocal?
Non-Focal. Multifocal dysplasia only.
Path of Osteochondritis Dessecans?
- Dysplasias at articular epiphyseal (AE) complex that form clefts in retained cartilage w/ subsequent fracture of overlying articular cartilage → cartilaginous or osteochondral flap
- If flap fractures off and floats free in joint → “joint mouse” → can interfere w/ mvmt of joint
What is cervical verterbral myelopathy (CVM) also known as?
Wobbler syndrome
What is cervical verterbral myelopathy (CVM) secondary to?
Compression/ irritation of the spinal chord.
2 types of spinal chord compression?
Static or Dynamic (both lead to CVM)
What animals are affected by static compression?
Horses 1-4yrs = Cervical static stenosis.
Dogs = cervical spondylomyelopathies.
Where do horses get static compression? What does this cause?
C5-7. Hypertrophy of the ligamentum flavum
What animals get Dynamic compression?
Horses 8-18mo = cervical vertebral instability
Where do horses get Dynamic compression?
C3-5
With what is Dynamic compression associated?
Rapid growth. Genetic
what is another name for Hemivertebrae?
Butterfly vertebrae
Path of Hemivertebrae?
partial development of vertebrae –> compression of spinal chord.
In what spp. is Hemivertebrae desired?
Bulldogs, Pugs, Boston Terriers.
corkscrew tail
Etiology of Growth Arrest Lines?
Viral (BVD, Canine distemper) Lead Toxicit (lead line)
Pathogenesis of Osteoporosis?
Imbalance between absorption and formation.
Increased resorption or decreased formation –> Atrophy.
Causes of Osteoporosis?
- Deficiency of Ca → deficient Ca for mineralization
- Malnutrition:
- Deficiency of protein, vitamin C, Cu → reduced bone formation.
- Lactational osteoporosis of young gilts → excess resorption. - Disuse: Physical inactivity and senility → excess resorption and decreased bone formation → disuse atrophy
- Toxicity:
- Vitamin A toxicosis → decreased osteoblastic activity –> decreased bone formation.
- Adriamycin toxicity → depressed osteoblastic activity
- Fluoride toxicity → abnormal osteocytes - Hypercortisolism, prolonged steroid therapy
- post-menopausal women
- Sterility –> decreased activity, hormones and vit D metabolites.
3 Lesions of Osteoporosis?
Decreased bone mass + Increased bone spaces:
- Cortical bone → decreased thickness, high porosity
- Trabecular bone → decreased thickness with perforations
- Medullary cavity → ENLARGED
Pathogenesis of Rickets (Rachitic Rosary)
Failure of calcification of osteoid and cartilaginous matrices → bones become soft and swollen.
Causes of Rickets?
- Low vitamin D (most common) → Hypocalcemia –> deficient osteoid mineralization and 2* fibrous osteodystrophy
- Also low Ca and P
Pathogenesis of Osteomalacia?
- MATURE softening of bones after growth plate closure.
- Unmineralized osteoid resistant to osteoclastic activity –>accumulates in bones fractures
3 Causes of Osteomalacia?
- Low Vit D → low Ca & P → high intestinal P absorption →lower Ca
- Chronic Renal Dz → low calcitriol → altered vit D metabolism → decreased vit D activity → decreased Ca absorption → decreased response to PTH → 2ry hyperparathyroidism
- Chronic Fluorosis