Radiology1- Fractures

  1. What is the radiographic technique for bones?
    • low KvP (for high contrast)
    • high mAs
  2. Where is the marker placed on rads of extremities?
    place L or R marker on the lateral side (cranially or dorsally on a lateral view)
  3. Describe proper positioning of bones and joints.
    • Bones: center on desired bone and include joint above and below
    • Joints: center on desired joint
  4. What surfaces of the bone/ joint are highlighted by a DLPMO radiograph?
    plantarolateral and dorsomedial surfaces
  5. What surfaces of the bone/joint are highlighted by the DMPLO radiograph?
    plantaromedial and dorsolateral surfaces
  6. With a hairline fracture [not large fracture line or displaced fractures], why is it important to take multiple views to find the fracture?
    your x-ray beam must be tangential (parallel) to fracture line for it to show up; if the beam is perpendicular to fracture line, it will not appear on the films
  7. If you see a relatively thin radiolucent area on the middle plantar/ medial aspect of a bone, what must you keep in mind?
    this is the location of the nutrient foramen; if the animal is not lame/ not showing signs, consider that it is NOT a fracture
  8. What are the salter-harris fracture classifications?
    • I: physis
    • II: physis and metaphysis
    • III: physis and epiphysis
    • IV: physis, metaphysis, and epiphysis
    • V: crushing injury to the physis
  9. Describe a transverse fracture.
    perpendicular to the long axis of the bone
  10. Describe oblique fractures.
    • no longer perpendicular to the long axis, at some different angle
    • can be short or long
  11. What is a spiral fracture?
    spirals around a long bone
  12. Describe a comminuted fracture.
    having multiple pieces
  13. What is a compound fracture?
    an open fracture in which the bone is sticking out past the margins of the skin
  14. What is a pathologic fracture?
    some disease process weakens the bone, making it easier to fracture with less trauma
  15. What is a slab fracture?
    starts on one margin of the joint and comes out the other edge of the joint
  16. The proximal row of carpal bones contains the __________, and the distal row of carpal bones contains the ___________.
    named carpal bones (ulnar, intermediate, and radial, acessory carpal bones); numbered carpal bones
  17. Within the proximal row of carpal bones, the carpal bone that is projected most proximally on a lateral flexed carpal radiograph is the ___________.
    intermediate carpal bone ("I is Hi")
  18. Within the proximal row of carpal bones, the carpal bone that is projected most distally on a lateral flexed carpal radiograph is the ___________.
    radial carpal bone
  19. What is an avulsion fracture?
    any piece of bone that’s attached to a soft tissue attachment (ligament/tendon) and is displaced by that ligament/ tendon
  20. Describe a compression fracture.
    • a bone that is pathologically weakened or fractures gets compressed/ becomes shorter
    • common in young farm animals that have an infection that weakens the bones (ex. young cria with compressed C7 vertebra)
  21. Describe a condylar fracture in a horse.
    • articular fracture at the distal aspect of the cannon bone (metacarpal or metatarsus)
    • common in athletic horses
  22. Why do we take post-op radiographs? (3)
    • document fixation
    • anatomic alignment
    • placement of implants (no implants in joints, engaging bone properly, etc)
  23. Describe the aspects of secondary bone healing.
    • most common way a bone heals
    • occurs by callus formation: initially, hematoma and inflammation--> bridge gap with granulation tissue--> resorption of fracture margins--> mineralization of granulation tissue--> eventual bone remodeling
  24. Describe the radiographic signs of secondary bone healing 5-10 days after reduction. (2)
    • fracture fragments lose sharp margins
    • demineralization of fracture margins, results in slight fracture line widening
  25. Describe the radiographic signs of secondary bone healing 10-20 days after reduction. (3)
    • formation of endosteal and periosteal callus
    • decreasing size of fracture gap
    • variable loss in opacity of free fracture fragments
  26. Describe the radiographic signs of secondary bone healing >30 days after reduction. (2)
    • fracture lines gradually disappear
    • external callus increases in opacity and models
  27. Describe the radiographic signs of secondary bone healing >3 months after reduction. (5)
    • continued remodeling of external callus
    • trabecular pattern may develop within the callus
    • cortical shadow becomes visible through the callus
    • medullary cavity continuity gradually re-established
    • cortical remodeling along the lines of stress
  28. What are factors affecting healing? (7)
    • anatomic reduction
    • stability
    • viability of surrounding tissue- a lot of muscle will aid in healing b/c more blood supply
    • specific bone involved
    • infection
    • fixation type
    • misc- species, breed, age, nutrition
  29. Describe primary bone healing. (3)
    • no cartilaginous phase (no callus)
    • excellent anatomic alignment
    • rigid fixation
  30. What are causes of lucency around a metallic bone implant?
    infection and/or implant loosening
  31. What is a classic sign of non-union?
    smoothing/ rounding of edges of fracture margins that are not united
  32. What is a malunion?
    anything that doesn’t heal in its normal anatomic alignment
  33. What is disuse osteopenia?
    • bone opacity is decreased, thinned cortical margins, coarse trabecular pattern
    • bone is resorbed d/t lack of loading of bone
  34. What is synostosis?
    when you have fractures especially with paired bones- sometimes they form one callus that incorporates both bones
Card Set
Radiology1- Fractures
vetmed radiology1