69. Misc Ortho Dz

Question 1

define osteochonrodysplasia

Answer 1

type of constitutive bone/cartilage diseaseoften heritable=abN endochondral and/or intramembranous ossificationdwarfism (disproportionate or proportionate)

Question 2

T/F most osteochondrodysplasias are disproportionate dwarfism

Answer 2

TRUE osteochondrodysplasias and nutritional deficiencies are disproportionate dwarfismUSUALLY dwarfism w disproportional SHORT limbs

Question 3

Hemimelia

Answer 3

APPENDICULAR DYSOSTOSEScongenital complete or partial absence of one of more BONESusually unilateralnot always heritable (except Chihuahuas, DSH, Siamese)usually non painfulterminal (transverse, longitudinal)intercalary (transverse, longitudinal)

Question 4

Hemimelia classification

Answer 4

terminal (transverse, longitudinal)-absence of all or some of the bones of a limb distal to a certain point . intercalary (transverse, longitudinal)-absence of all or some of the middle bones of a limb with the proximal and distal bones still present (middle one is missing)transverse: complete absence across the limbs widthlongitudinal: absence along the medial or lateral side of a limb

Question 5

radial hemimelia

Answer 5

usually pre-axial (medial) intercalary longitudinalusually unilateral, marked varus, unable to bear weight, flexure deformitysurgery: declaw (palliative), arthrodesis + reconstruct radial defect (graft, distraction osteogenesis), amputate

Question 6

dimelia

Answer 6

APPENDICULAR DYSOSTOSEScongenital duplication of the whole or part of a limbdog (not seen in cat)figure out which is nonfunctional and amputate it

Question 7

ectrodactyly

Answer 7

APPENDICULAR DYSOSTOSEScongenital digital cleft formation extending between metacarpal bonesmost btwn 1 and 2 metacarpal bonesunilateral usually of thoracic limbs

Question 8

polydactyly

Answer 8

APPENDICULAR DYSOSTOSESpresence of one or more extra digitspreaxial (medial); post axial (lateral)normal autosomal recessive trait in St Bernards, Collies—medial pelvic limb

Question 9

syndactyly

Answer 9

APPENDICULAR DYSOSTOSESlack of ddx btwn two or more digits simple vs complexcomplete vs incomplete

Question 10

HOD signalment and presentation

Answer 10

2-6 months of ageLarge -giant breed dogs (Weimaraners)Males are 2.3 times more likelyMetaphyseal swelling (distal RU and tibia most common)Often bilateral+/- pyrexia, pain, warmth

Question 11

List pediatric bone diseases

Answer 11

–Hypertrophic osteodystrophy HOD–Panosteitis–Craniomandibular osteopathy–Retained ulnar cartilagenous core–Legg calve perches disease–Femoral capital physeal dysplasia–Multiple cartilaginous exostoses

Question 12

Possible etiologies for HOD

Answer 12

Vitamin D insufficiency (scurvy)Heritable (Weimaraners 0.68 inherited immunodeficiency w low Ig)Infection (blood culture)Canine distemper virus

Question 13

Pathognomonic radio graphic sign of HOD

Answer 13

Lucent line in the metaphysis parallel to a narrow zone of increased radiodensity immediately immediately adjacent to the physiscan also see see metaphyseal “flare” or widening of the bone

Question 14

Panosteitis signalment and disease progression

Answer 14

Self limiting Inflammatory disease of the bone marrow of long bonesShifting leg lameness w long bone pain5-12 months - up to 5 YO (older than HOD)Large-giant breed Males 4:1eosinophilic inflammation!

Question 15

Radiographic diagnosis of panosteitis

Answer 15

Early (rare)- decreased radiodensity evident in medullary cavity near nutrient foramen (changes in intraosseous pressure to increase with vascular congestion–maybe from protein accumulation)Later- increase in medullary opacity w granular pattern or w loss of the normal trabecular pattern+/- Periosteal bone formation as it progresses the medullary canal becomes more diffuse and homogenous

Question 16

Treatment of panosteitis

Answer 16

RestAnalgesicsSelf limiting Benzopyron (not available) proteolytic substance to decrease intraosseous pressure+/- recurrence

Question 17

Craniomandibular osteopathy CMO

Answer 17

<6-12 months of ageWest highland white terriers, cairn, Scottish terriersSuggests heritable causeUnilateral or bilateral symmetric irregular osseous proliferation of mandibles and/or temporal bonesPain, dysphagia or inability to eat/drinkSalivation Self limiting at 11-13 mo of agemale = female

Question 18

Retained ulnar cartilagenous core

Answer 18

Viable hypertrophic chondrocytes that project from the distal ulnar growth plate into the distal metaphysis with failure to convert to metaphyseal bone. Can lead to ALD from radial bowing, elbow incongruity, carpal valgusradiolucent core (triangle) of cartilage distal to metaphysis +/- surrounded by a zone of sclerosisMay need surgical correction if severe

Question 19

Legg calve perthes

Answer 19

Avascular necrosis of femoral headNo inflammatory local ischemiaSmall breed dogs– toys & terriers1. necrosis2. fragmentation (apple core)3. collapse/thickening 4. revascularize/reossification

Question 20

how many bilateral presence of Legg Calve Parthes

Answer 20

12-17%

Question 21

treatment for legg calve perthes

Answer 21

only 25% resolve lameness with conservative mgmt–FHO–THRpx 84-100% with surgery

Question 22

signalment for slipped capital femoral epiphysis

Answer 22

through the growth platenontraumatic ( NOT SH 1 fracture)CATS–male neutered young overweight (may be related to early neuter and hypotestosteronism)often BILATERAL

Question 23

multiple cartilaginous exostoses

Answer 23

young dogsold cats (FeLV)may or may not have malignant transformationmay occur from secondary migration of chondrocytes from the physis into metaphysissingle (osteochondroma) or multiple well circumscribed calcified lesionsaffects vertebra, ribs. long bones

Question 24

most common reason for surgical excision of cartilaginous exostosis

Answer 24

vertebral exostosis causing spinal cord compression

Question 25

causes of metabolic bone disease

Answer 25

–primary HPT–nutritional or renal secondary HPT–vit D toxicoses–hypo vit D (ricketts)–hypo/hyper vit A–hypovit E**most often affect Ca metabolism/homeostasis—osteopenia and brittle bones seen

Question 26

osteogenesis imperfecta

Answer 26

metabolic bone diseasedisruption in collagen I

Question 27

hypertrophic osteopathy

Answer 27

HO—older dogsassociated with neoplasia (abdominal, thoracic) can also be nonneoplastic (spirocerca lupin, heart worm dz)periosteal reaction of DISTAL (diaphyseal) extremities due to peripheral blood flow changes stimulating an overgrowth of vascular connective tissue and periosteal proliferation radiographs appear aggressive or nonaggressive. look for palisade formation of bone

Question 28

disseminated idiopathic skeletal hyperostosis

Answer 28

spinal and extraspinal manifestation of heavy bone formationlimited spinal ROM1. continuous flowing calcification > 3 vertebra2. relative preservation of disc space3. periarticular osteophytosis around zygapophyseal joint4. pseudoarthrosis btwn spinous processes5. periarticular osteophytosis and calcification of soft tissuesneed 4 out of 5 to make dx

Question 29

T/Fbone cysts are lined by epithelium

Answer 29

FALSEbone cysts are lined by fibrous connective tissueyounger larger breed dogs (male 2:1), Dobiesradiographs reveal expansile, locally aggressive lucent lesion with minimal to no periosteal reaction, most are eccentrically located, most involve metaphysis and diaphysis

Question 30

acute caudal myopathy

Answer 30

limber tailpointers and labradorspainful at base of tail and tail is flaccidusually after extreme exertionself limiting but can recur

Question 31

swimmer syndrome

Answer 31

flat-pup, turtle-pupneonates affectedsternal with splayed legspectus excavatumneed physical rehab in first 3 weeks, prognosis can be good

Question 32

puppy carpal laxity syndrom

Answer 32

carpal hyperextension >180 degrees (dropped hock)OR carpal hypo extension < 180 degrees uni or bilateral; self limited +/- splints/braces65% recover in two weeks

Question 33

normal flexion in carpus vs hypoflexion

Answer 33

flexion 20-30 degreeshypoflexion (older dogs) >30 degrees

Question 34

iliopsoas muscle injury

Answer 34

attaches to lesser trochancter of femurdiscomfort on extension and internal rotation of hipneed rehab and rest +/- NSAIDssevere cases—tenomyectomy