Skeletal Imaging

    • author "me"
    • tags ""
    • description "Radiographic differential diagnosis"
    • fileName "Imaging"
    • freezingBlueDBID -1.0
    • Aseptic necrosis -legg calve perthes disease

    Bilateral or unilateral collapse of the femoral neck with a moth eaten appearance of the femoral head.
  1. Flattened surface of femoral head due to collapse of subchondral bone
  2. Acute osteoarthritis
    Caused by an underlying abnormality in the joint or supporting structures

    No bony changes but there is effusion in the effected joint
  3. Chronic osteoarthritis
    Caused by an underlying abnormality in the joint or supporting structures

    Bone remodelling in periarticular tissues (osteophyte formation) + joint capsule thickening

    Joint effusion (increased soft tissue opacity in the joint)
  4. Primary bone tumour
    Occur primarily in the metaphyseal region

    Destructive lesion of bone + periosteal reaction

    Tends to only affect a single bone and lesion rapidly changes
  5. Soft tissue tumour with bone invasion
    Invades bone by direct extension - have bone and cortical erosion where the soft tissue tumour invaded

    Occurs in diaphysis
  6. Metastatic tumour
    Occurs within the diaphysis (humerus and femur). May affect numerous bones

    Multiple opacities within the medullary cavity + periosteal reaction
  7. Osteomyelitis
    Infection of the bone usually centered in the medullary cavity (although it can localise at sites of active endochondral ossification in the metaphysis and epiphysis of long bones and vertebral bodies)

    Aggressive lesion- may see a sequestrum
  8. Osteochondrosis (OCD)
    Rough and bumpy articular surface (sclerosis due to lack of cartilage ossification)

    Joint effusion

    Predilection sites - caudal aspect of the humeral head + dorsal ridge of medial trochlear of hock
  9. Discospondylitis
    Infection of the intervertebral disc space -> disc space collapse -> end plates become sclerotic and irregular due to spread of infection

    New bone formation on ventral vertebral bodies
  10. Femoral neck fracture
    Occurs along the capital epiphysis (just below the ball of the femoral head). The femoral head remains in the acetabulum whilst the shaft of the femur moves around
  11. Pathological fracture
    Bone shows an underlying abnormality that lead to the bone being weakened

    Bone may contain multiple fractures
  12. Avulsion fracture
    Where a small chip has been pulled off bone by a tendon or ligament => this occurs where tendons and ligaments attach to bone
  13. Non-Displaced fracture
    Fracture appears as a crack because the broken pieces are still in alignment
  14. Collateral ligament damage - joint instability
    Severe gaping of joint on one side (instability)

    Avulsion of bone at an attachment site (periarticular bone fragment)

    Joint effusion + predominantly unilateral soft tissue swelling
  15. Radius curvis- short ulnar syndrome
    Shortened ulnar and cranial bowing of the radius due to premature ulna physis closure

    Irregular and thickened cortices of the radius

    Visible horizontally distributed trabecular bone within the radius
  16. Short radius syndrome
    Shortened radius due to premature closure of the radial growth plate

    Increased humeroradial joint space
  17. Hip dysplasia
    Subluxation of the hip joint due to lack of conformity between the acetabulum and the femoral head

    Causes the centre of the femoral head to be outside the line of the dorsal acetabular rim

    Secondary changes- osteophyte formation over the femoral neck and over the cranial acetabular edge
  18. Vertebral fracture
    Alters vertebral alignment +/- compression and shortening of the vertebral body

    Stair step = subluxation of a vertebrae + fracture fragment

    Young animals- fracture through the physis "end plates" of the vertebral body
  19. HOD (metaphyseal osteopathy)
    Alternating radiodense and radiolucent zones in the metaphysis of long bones, parallel to physis "double physeal line". This irregularity is due to necrosis of bone.

    May progress to develop periosteal and extraperiosteal new bone around the metaphysis (bony reaction)

    Often bilateral and often ulna and radius. Occurs in young dogs => growth plates are open.
  20. Panosteitis
    Increased opacity in the medullary cavity in the diaphysis of long bones => cannot easily differentiate between cortex and medulla

    Occurs near the nutrient foramina.

    Periosteal reaction can occur

    Endosteal proliferation of new bone => bumpy endosteal surface
Card Set
Skeletal Imaging
Skeletal Imagin Differential Diagnosis