DI Exam 3 - neurology, orthopedics

Neuroradiology

Neuroradiology

• Covers head and axial skeleton

• Based off of symmetry

• General anesthesia is a must

Hydrocephalus

• Cause:

  • Overproduction or obstruction to outflow of CSF: choroid plexus

    • high production, low absorption

  • Congenital or acquired

    • Dome head toy breeds

• CS:

  • dull mentation, seizures, incoordination

• Views:

  • Closed mouth VD and lateral

    • 5% will show x-ray signs

• RS:

  • Open fontanel and suture, caudal osseous tentorium, ground glass look, thin cortex, dilated lateral ventricles

    • Adults, may look normal

Occipital Dysplasia

• Cause:

  • Congenital defect of foramen magnum

    • young Dome head toy breeds

• CS:

  • cervical pain, hind limb neurologic deficits

• Views:

  • Lateral, closed mouth VD, slight obliqued VD

  • Needs MRI/CT scans

• RS:

  • Abnormal foramen magnum with open dorsal extension

    • “keyhole” shape

    • herniation possible

Chiari Syndrome

• Cause:

  • King Charles Cavalier Spaniels

• CS:

  • neck pain, mentally dull, ear scratching

• RS:

  • Caudal crowding of the cerebellum with herniation via foramen magnum

    • Normal X-rays

Cranial Mandibular Osteopathy

• Cause:

  • Unknown but self limiting

  • Young westies

    • 4-11 months

• CS:

  • Pain, cant open mouth, muscle atrophy, Soft tissue swelling

• Views:

  • Closed mouth VD and lateral view

• RS:

  • Osteoproductive lesion of mandible/TMJ/bulla, NO lysis

Otitis Media

• Cause:

  • Bacteria mid ear infection

    • secondary to chronic otitis external

  • Floppy eared old dogs

• CS:

  • Head tilt, ear pawing, exudate, seizures

• Views:

  • Closed mouth VD, open mouth VD, obliques

    • CT / MRI is preferred

• RS:

  • Thick osseous bulla with lysis, increased soft tissue density in bulla, mineralization of external ear canals, increased opacity of tympanic bullae, nasopharyngeal polyp

Normal contents of the ear

• tympanic bullae

  • air

• external ear

  • air

X ray positioning of the head

• Done sedated

• Open mouth VD

  • #1 for nasal passages

  • Closed mouth obstructs passages

• Lateral View

• Frontal Sinus View

• X-rays are insensitive for nasal dx

  • CT preferred

Destructive rhinitis

• Cause:

  • Neoplastic

    • Old, Lg dolichocephalic dogs (long)

    • Adenocarcinoma

  • Fungal rhinitis

    • Lg dogs

    • Aspergillus + blastomycosis

• CS:

  • Mucopurulent to bloody discharge

  • Neoplastic: Uni to bilateral discharge, facial deformity’s, external masses

  • Fungal: Uni discharge, facial/external deformities are RARE

• Views:

  • Open mouth VD, lateral, skyline frontal sinus

    • X-rays insensitive for nasal dx

    • CT prefered

• RS:

  • Increased nasal passage opacity, turbinate destruction, bone lysis

Non-destructive rhinitis

• Cause:

  • Older animals

  • Bacti, fungal, viral, FB, allergys, parasites, Kartagener’s

• CS:

  • Serous to mucopurulent discharge

• Views:

  • Open mouth VD, lateral, skyline frontal sinus

    • X-rays insensitive for nasal dx

    • CT prefered

• RS:

  • Increased nasal passage opacity, nasal turbinates blurring, NO lysis or septal deviation

Temperomandibular Joint TMJ

• Cause:

  • Congenital or acquired

• CS:

  • luxation, instability of the jaw, weight loss, pain, cant open mouth

• Views:

  • Closed mouth VD, obliques

• RS:

  • irregular articular surfaces, joint incongruity, luxation, DJD

Spinal anatomy

• Rib heads

  • articulate in front of their assigned #

• 7 cervical vertebrae

  • C2 dorsal arch over lap C1

  • C 2-3 narrow disc space

  • C6 Lg lamina ventral to transverse process

    • sled runners

  • C7 dorsal spinous process in Lg

• 13 thoracic vertebrae

  • C7-T1 narrow disc space

  • T10-11 narrow disc space , bulb articular process

  • T11 anticlinal vertebrae, straight dorsal spinous process

  • Dorsal spinous process point caudally

  • Disc herniation are rare cranial from T1-T10

• 7 lumbar vertebrae

  • L3 and L4 attach diaphragm

  • Transverse processes increased opacity

  • Dorsal spinous process point crainally

• 3 sacral vertebrae

  • 20-23 coccygeal vertebrae

• Accessory process

  • increased disc opacity

  • overlay the intervertebral foramen and insults in increased opacity within the neurocanal

  • often not present

Atlantoaxial Instability

• Cause

  • Congenital (95%)

    • malformation of dens C2

    • lig. malformation

    • Mini dogs

  • trauma to dens

• CS

  • Ataxia, paralysis, proprioception issues, cervical neck pain, shows up under 1yr old

• Views

  • Straight lateral C-spine, lateral dens view, slightly flexed lateral, VD

• RS

  • C1- C2 large joint space, Sm/missing dens, dens fracture

• DDx.

  • disk herniation, neoplasia, trauma, central CNS dx

Block vertebrae

• @ any location

• Cause

  • Congenital

  • Boxers, Bulldogs, Bostons, Shar Pei, Chondrodystrophoids, Manx

  • failure of proper segmentation

• CS

  • stable, incidental, can cause surrounding aging issues

• RS

  • vertebrae fusion, lack of disc

Hemivertebrae

• Cause

  • Congenital

  • Bostons, bulldogs, pugs

• CS

  • incidental, stable

• RS

  • Abnormally shaped or short vertebra, odd curvature of spine

  • 50% less then other vertebra

Transitional Vertebrae

• Cause

  • Congenital

  • Boxers, Bulldogs, Bostons, Shar Pei, Chondrodystrophoids, Manx

  • anomalous formation of TL and LS junctions

• CS

  • incidental

• RS

  • Sacralization of L7 via illiac fusion

  • Lumbarization of S1 via transverse process/disc development

Terms used to describe vertebral curvature

• Lordosis

  • Ventral deviation of spine

    • looking at the lord

• Kyphosis

  • Dorsal deviation of spine

• Scoliosis

  • Lateral deviation of spine

Spina Bifida

• Cause

  • Congenital malformation and failure of fusion of dorsal arches

  • Bostons, bulldogs, Pug, Manx

    • screw tails

  • failure of fusion of dorsal lamina on dorsal arches and spinous processes

• CS

  • Young: clinical

  • Old: non-clinical

• Views

  • Lateral and VD

• RS

  • 2 paired dorsal spinous processes, missing/blunted L7 dorsal spinous, distended colon or bladder

  • SB occulta= bony defect

  • SB manifesta= meninges and spinal cord herniated through bony defect

Spondylosis Deformans

• Cause

  • Joint instability, idiopathic

  • Degenerative

    • Animals over 1yr

  • Bone exostosis projecting from the

    vertebral endplates

• CS:

  • No CS, incidental

• Views

  • Lateral and VD

• RS

  • Smoothly marginated, bony bridging

Discospondylitis

• Thoracic and lumbar spine are the most common sites

• Cause

  • Bacti infection of discs and end plates

    • staph, strep, e coli, brucella

    • Hematogenous infections

    • can be secondary

      • septic emboli

  • GSD, Danes, Males

• CS

  • Young, focal back pain, reluctance to move or ambulate, neuro deficits to limbs, bony lysis

• Views

  • Lateral and VD of entire spine

• RS

  • Osteolytic focal lesion, wide/narrow intervertebral disc space

Spondylitis

• Cause

  • Bacti infection of ventral vertebral body

    • staph, strep, e coli, brucella

    • Hematogenous infections

    • can be secondary

      • septic emboli

• CS:

  • Middle age to older dogs and cats, <2 years most commonly, back pain, reluctance to move or ambulate, neuro deficits to limbs, fever

• Views

  • Lateral and VD

• RS

  • Loss of vertebral body concave margin, bony productive lesion on ventral vertebral body, rough

Intervertebral Disc Disease

• Cause

  • disc protrusion or extrusion of nucleus pulposis

  • Type 1

    • calcification in situ, acute herniation

    • chondrodystrophoid dogs

  • Type 2

    • Incomplete with slower onset

  • Rare @ T1-T9 due to intercapital ligament

• CS

  • Older, pain, paralysis

• Views

  • Lateral and VD: cant diagnose

  • MRI

• RS

  • Narrow disc space, increased intervertebral opacity, mineralized disc

Myelogram

• iodinated contrast: agent injected around spinal cord space surrounding (subarachnoid space)

  • specific nonionic, low osmolar agent

  • Iohexol or omnipaque

• ID areas of cord compression or deviation

  • Extradural

    • Lesion outside dura mater

  • Intradural-extramedullary

    • Lesion in subarachnoid space

  • Intramedullary

    • Lesion in spinal cord

• Complications

  • invasive

  • seizures, vomiting, bradycardia, exacerbation of neuro issues, death

Vertebral Tumors

• Primary tumors: stops growing when pet stops growing

  • usually located in only one vertebral body

    • Except Osteochondroma or multiple cartilaginous exostoses

      • Multiple vertebrae and/or ribs

  • Most are lytic

  • Osteosarcoma is most common

• Metastatic Tumors

  • multiple vertebral bodies

    • tumors through body

  • lytic or periosteal

• RS

  • osteolytic or osteoblastic lesions, compression

  • MM: multiple areas of moth-eaten diffuse lysis

  • MCE: bony mass displacing and compressing the Spinal cord

Cervical Vertebral Instability (Wobbler’s Disease)

• Cause

  • Inheritable

  • Great Danes, Dobermans

  • cervical disc spaces are unstable, spinal cord interference, dorsally displaced vertebral body, hypertrophy of dorsal longitudinal lig. disc protrusion/extrusion

• CS

  • Old, male, ataxia, cervical pain, hemi to tetraparesis, wide based stance

• Views

  • Straight lateral and VD

    • myelography and dynamic views

    • 80% can be ID with x-rays (controversial)

• RS

  • Narrowed/wedge disc space, dorsal deviation of vertebral body, spinal mal alignment of C5-6, C6-7, C4-5, cord compression that worsens during neck extension

Lumbosacral Instability

• Cauda Equina Syndrome

• Cause

  • Instability of L7-S1, disc protrusion or extrusion, hypertrophy of dorsal longitudinal lig.

  • Transitional vertebrae may predispose

  • GSD

• CS

  • older, rear limb ataxia, worn dorsal nails, pain during full extension of pelvis, reluctance to position to defecate

  • Fecal and urinary incontinence

• Views

  • Lateral and VD

  • Need MRI

• RS

  • Narrowed/wedge, Spondylosis, ventral step lesion at L7-S1

  • Full colon

Hyperparathyroidism

• Cause

  • hyperfunctional parathyroid gland

  • hypercalcemia caused by the elevated PTH.

  • Primary Hyperparathyroidism from adenoma of the parathyoid gland

  • Secondary Hyperparathyroidism from diet or chronic renal failure

• RS

  • Skull demineralization, generalized osteopenia with cortical thinning, prominent endplates, prominent teeth opacity

Radiology and skeletal healing

• Normally must have 30-50% bone loss prior to seeing it

• Lytic changes will not be seen for 7-10 days

• Productive changes may not be seen for 14 days

Soft tissue radiology

• Extracapsular tissue swelling

  • Blood, pus, edema outside joint

  • Not centered around a joint

• Intracapsular tissue effusion

  • Blood, pus, edema within a joint

  • Centered around a joint space

• Soft Tissue Emphysema

  • Gas inside body

    • Outside: petrating injury or sx

    • Bacti sorce: emphysematous bacteria like Clostridia

    • From body: pneumoarthrogram (cracks)

• Soft Tissue Mineralization

  • Dystrophic

    • Focal

    • Dead, dying tissue

    • Metaplasia to mineral

    • Normal Ca:P

  • Metastatic

    • Diffuse

    • Abnormal Ca:P

Periosteal Reactions

• Healing process in response to injury with Sharpey’s fibers

• Solid / Homogeneous

  • Periosteum is lifted and new bone has filled space beneath it

  • well defined

• Lamellated

  • alternating opacities

  • cyclic ongoing processes

  • Active, aggressive lesions

    • Osteomyelitis, fungal disease, neoplasia

• Spiculated

  • spicules at right angles with the bone

  • pus, neoplastic cells between spicules

  • Form along Sharpey’s fibers

  • aggressive process

    • infection, neoplasia, fungal

• Amorphous “wispy”

  • Looks like anything

  • Aggressive process

    • neoplasia

• Codman’s Triangle

  • Lifting of periosteum by radiolucent cells at lesion edge

  • aggressive processes

    • osteomyelitis, neoplasia

Osteoporosis

• Cause

  • overall decrease bone mass

    • normal composition just not enough

  • Old, Cushing’s, hyperparathyroidism, Addison’s, steroids, low calcium

• RS

  • Cortical thinning, bone lucency, prominent trabeculation, “egg shell” vertebral bodies

Osteomalacia

• Cause

  • abnormal matrix, normal mass

    • “Soft bone”

  • CKD, low vit D or Ca

  • Hypophosphatemia

• RS

  • decreased bone opacity, cortical thinning, angular limb deformities

Osteopenia

• Generalized term to describe focal or generalized decrease in bone density

Osteosclerosis

• Cause

  • increase in bone mass

  • hormonal imbalance (female birds), metabolic, neoplasia, incidental (cats)

• RS

  • thick cortical thickening, increased marrow opacity

Focal or Regional Bone Loss

• Disuse osteoporosis

  • 50% loss before seen

  • 10d “no use”

• Geographic bone loss

  • Focal lytic lesion in bone

  • Center is necrotic/pus

  • May be expansile

• Punctate (permeative) lysis

  • Multi, sm lysis regions

    • can coalesce

  • Indistinct margins

  • Aggressive process

Bone Parts

• Epiphysis

  • end of bone, articular part

• Physis

  • growth plate or line

  • Distal radial plate

    • 80% of growth, closes 9 mths

  • Distal ulna plate

    • 85% of growth, closes 10 mths

• Metaphysis

  • widened part between shaft and growth plate

• Diaphysis

  • shaft of long bone

Growth Plate Injuries

• Cause

  • skeletally immature < 10 months

• Salter Type I

  • Separation entire physis

  • shearing forces

  • good prognosis

• Salter Type II

  • most common

  • through physis and metaphyseal

  • triangular shaped bone frag

  • good prognosis

• Salter Type III

  • through articular surface, epiphysis and physis

  • intra-articular shearing force or a torsional force

  • Fair prognosis

• Salter Type IV

  • through epiphysis, physis, and metaphysis

  • often older animals

  • poor prognosis

• Salter Type V

  • through physis

  • severe crushing forces

  • poor prognosis

Premature Physis Closure

• Distal Ulnar

  • Short ulna

  • Radius may bow

  • Distal radius is subluxated craniomedially from the radial carpal bone

  • foot deviates laterally

  • wide humero-ulnar joint

  • common

• Distal Radial

  • Short radius

  • Wide radiocarpal and radiohumeral joint space

  • elbow/carpus degeneration

Fracture classifications

• Open Fracture (compound fracture)

  • exposed to enviro

• Closed Fracture (simple fracture)

  • contained in the body

• Incomplete Fracture

  • partial break

  • immature animals “greenstick” fracture

• Fissure Fracture

  • incomplete fracture off of a complete fracture

• Depression Fractures

  • multiple fissure fractures

  • common in skull

• Complete Fractures

  • complete loss of bony continuity

    • deformed

• Transverse Fracture

  • transverse to the long axis

  • bending forces

• Oblique Fractures

  • oblique to the long axis

  • two cortices of each fragment are in the same plane without spiraling

  • bending forces

• Spiral Fractures

  • fracture line that spirals along the long axis

• Comminuted Fracture

  • +3 interconnected fractures

  • high energy trauma

• Multiple Fracture

  • +3 not interconnected fractures

• Impaction or compression fracture

  • bony fragment forced into cancellous bone

  • end of long bones

• Avulsion Fracture

  • violent contraction of a muscle rip off bone

• Chip fracture

  • fragment

• Slab Fracture

  • expansile articular fracture

• Pathological Fracture

  • secondary to disease

Bone Healing types

• Primary

  • ideal

  • direct growth of an Haversian system

  • does not occur across fracture gaps

  • RS

  • Lack callus

  • Gradual decreased opacity and fracture line

• secondary

  • common

  • when rigid internal fixation does not exist

Factors That Affect Bone Healing

• Vascular Integrity

• poor blood flow reduces healing

• Location

  • Metaphyseal heal faster

  • diaphyseal heal slow

  • antebrachial heal slow

  • Cancellous bone heal fast

  • Cortical bone heal slow

• Mobilization

  • rigidity heals fast

• Type

  • complicated heals slow

• Postreduction Apposition

  • good apposition heals fast

• Age

  • young heals fast

• Local Trauma

  • with severe soft tissue injury heals slow

  • infectsion slows healing

  • malignancy slows healing

• Bone loss

  • excessive distraction heals slow

• Corticosteroids

  • slow healing

  • inhibit the differentiation of osteoblasts

Evaluation of fractures

• alignment, joints, rotation, fixation

• Tx. Sx or casting

  • 6 cortices engaged with screws above and below the fracture site

• Complications

  • Malunion and warping

    • hard to see in young dogs till mature

  • Delayed Union

  • Non Union

    • no healing for 90d

    • atrophy of region

    • Hypertrophic

      • lysis

      • Cortical discontinuity

      • Non bridging callus

      • angular deformity

    • Atrophic

      • Min callus formation

      • defined gaps

Osteochondrosis

• Cause

  • dysfunction of endochondral ossification

  • thick weak cartilage

    • chips off

• CS

  • young Lg breed males

  • front limb lameness

• Location

  • Shoulder (#1): caudal or caudal-lateral humeral head

  • Elbow: distal medial humeral condyle

  • Stifle: distal lateral femoral condyle

  • Tarsal: medial trochlear ridge of the talus

• RS

  • Calcified flap of articular cartilage, secondary DJD, Joint effusion

• DDx

  • long digital extensor fossa can be confused for an OC lesion

Fragmented Medial Coronoid Process

• Cause

  • Young Lg male dogs

  • elbow dysplasia

• CS

  • Stiff front end, lameness, elbow pain, DJD in older animals

• Rs

  • osteoarthritis, osteophytes on the anconeal process and radial head, sclerosis of the trochlear notch of the proximal ulna, repair on medial coronoid process of the ulna

Ununited Anconeal Process

• Cause

  • Anconeal process forms from a separate center of ossifications

    • unfused

  • Young Lg dogs

    • GSD

• CS

  • weight bearing lameness

• RS

  • Irregular radiolucent line cross the anconeal process

Retained Cartilaginous Core

• Cause

  • Young Lg dogs

  • Unknown

  • core of cartilage in the metaphysis

  • issue of osteochondrosis of the distal ulnar physis

  • cartilage does not transform into bone

• CS

  • self limiting

  • retard growth of the distal ulnar physis causing angular limb deformity

• RS

  • Conical shaped radiolucent zone extending from the distal ulnar physis into the distal ulnar metaphysis

Panosteitis

• Cause

  • Young male Lg dogs

    • GSD

• CS

  • self limiting, front limb lambess, front limb long bone pain

• RS

  • Increased intramedullary opacity, blurring of the trabecular pattern, patchy medullary opacities, rough endosteal surface

Hypertrophic Osteodystrophy

• Metaphyseal flaring – lacy bony appearance around physeal

• Cause

  • Young Lg male dogs

• CS

  • Self limiting, lamness, painful, swelling around long bones, Pyrexia

• RS

  • necrotic marginated line parallel to physis, metaphyseal flaring

Legg Calve Perthes Disease

• Cause

  • Young SMALL dogs

  • necrosis of the capital femoral epiphysis from poor blood supply

  • Unilateral

• CS

  • Weight bearing lameness, leg pain

• RS

  • Increased width of joint space and opacity of femoral head, patchy lysis

• FHO sx

Hypertrophic Osteopathy

• Cause

  • old dogs with lung dx

  • Hormonal, neural, hypoxia

  • Begins on the abaxial surface of digit 2,5 and moves proximally

• CS

  • pulmonary dx or masses, 4 limb lameness, distal limb swelling

• RS

  • irregular periosteal reaction of tubular bones and accessory carpal/calcaneous

Degenerative Joint Disease

• Cause

  • multifactorial, non-septic disorder of synovial joints

  • deterioration of articular cartilage leading to inflammation of joint

• CS

  • slow onset progressive intermittent lameness, work out of lameness with movement

• RS

  • Intracapsular swelling

  • Increased joint space if acute, decreased size if chronic destruction of the cartilage

  • articular cartilage proliferation in non weight bearing areas

    • cartilage proliferation outgrows it nutrient supply

  • Perichondral osteophytes

  • Detached pieces of articular cartilage, Joint “mice”

Septic Arthritis

• Cause

  • Adults with penetrating wounds or no wound history in puppies

  • Joint infection

• CS

  • Severe pain and joint effusion, lameness, fever, anorexia, lethargy, single joint (except puppies)

• RS

  • tissue swelling, chronic bony changes, gas in tissue, lysis, severe subchondral erosion

Hip Dysplasia

• Cause

  • High estrogen

  • Lg dogs

    • GSD

  • genetic or environmental

  • laxity of the coxcombical joint

• 3 months to 3 years (often worse at 9-11 months) or at old age

• CS

  • lameness, pain, restricted potion, difficulty standing and climbing

• RS

  • cranial joint wedging, <1/2 of the femoral head covered by dorsal acetabular rim, thick femoral neck, shallow flat acetabulum, osteophytes

• Evaluation

  • Penn Hip: 4mths

    • measured distance between the femoral head center and the acetabular center with pressure added

    • 0 = tight

      • >0.4= high risk

    • 1= luxated

  • OFA

    • must be 24m of age or older

    • extended VD view evaluated by radiologists for subluxation, shallow acetabula, remodeling, osteoarthritis

    • Excelent = improved

    • Good= normal

    • Fair= minor issues

    • Borderline= marginal issues

    • Mild= minor dysplastic changes

    • Mod = defined dysplastic changes

    • Severe = marked

• TX.

  • Triple Pelvic Osteotomy in young dogs, hip replacement, Femoral Head and Neck Ostectomy as a salvage procedure

Cranial Cruciate Disease (CCL)

• Cause

  • Young athletic (acute) or fat dogs (chronic)

  • degeneration, separation, weaking of the lig

• CS

  • Non weight bearing lameness, patellar luxation

• RS

  • cranial tibia displacement, “Rad Drawer sign”, Intracapsular swelling squishing fat pad, joint mice from evulsion fracture, swelling of the medial joint capsule (medial butrus), osteoarthritis

Patellar Luxation

• Cause

  • Medial young sm dogs

  • Lateral young Lg dogs

  • congenital or traumatic

• CS

  • lameness

• RS

  • Patella is medial to trochlear groove, lateral bowed distal femur, Medial proximal tibia bowing and quadriceps muscles, shallow tronchlear groove, osteoarthritis

Arthridities

• Destructive (erosive)

  • Lysis and erosion of articular and cortical bone

  • Narrow joint

  • Intracapsular effusion

• Non-destructive (non-erosive)

  • no Lysis or erosion of articular and cortical bone

  • Narrow joint

  • Intracapsular effusion

Erosive Polyarthritis

• Cause

  • most common is Rheumatoid Arthritis

    • carpal and tarsal bones

  • Middle aged Sm poodles and shelties

  • granulation tissue invasion, collagenase damages capsule and lig

• CS

  • shifting lameness, low grade, fever, anorexia, and slight generalized lymphadenopathy

• RS

  • lucent, cyst-like subchondral lesions, narrow joints, subluxation and luxation

Osteomyelitis

• Cause

  • Fungal or bacterial infections, often resp invasion

    • Blastomyces dermatitidis (south)

    • Coccidioides immitis (west)

    • Histoplasma capsulatum

    • Cryptococcus neoformans & Aspergillosis

    • 40% polymicrobial

    • 15% anaerobic

• Lg mid age male dogs

  • working breeds

• CS

  • local swelling, draining tract, lameness, systemic dx

• RS

  • lysis and productive changes, periosteal reaction, sclerosis

Primary Bone Neoplasia

• Cause

  • Lesion usually solitary in long bones

  • Osteosacrcoma #1

• Signalment

  • Lg mid age male dogs

• CS

  • Swelling, lameness

• RS

  • aggressive osteoblastic or osteolytic metaphyseal leasons, do not cross joints

  • “Toward the knee and away from the elbow”

Multiple Myoloma

• Purely lytic

• “punched out” of flat bones

• Little to no periosteal reaction

• No bony production

Benign Bone Cysts

• Cause

  • unkown

• CS

  • none, can cause pathologic fractures

• RS

  • Expansile, lucent, bony lesion with decreased trabecular markings, No periosteal reaction, Sharply defined zone of transition, Cortical bone thinning, no lysis

Benign Bone Tumors

• Cause

  • Osteochondroma, osteoma, odontoma, exostosis

• Signalment

  • Old animals

• CS

  • asymptomatic

• RS

  • Sharp transition, min periosteal reaction, no lysis, osteoproduction

Metastatic Bone Neoplasia

• Cause

  • Prostatic adenocarcinoma, transititional cell carcinoma, mammary adenocarcinoma

• Signalment

  • Old animals

• CS

  • generalized bone pain

• RS

  • Diaphyseal reactions

Synovial Cell Sarcoma

• Cause

  • Unknown

  • arises from tendon sheath or synovial lining

• Signalment

  • Old Lg dogs

• CS

  • joint pain and swelling, lameness

• RS

  • metastasis, lobulated soft tissue swelling, lysis of lg appendicular joints

• Next step — Chest xrays!