Diagnostic imaging of bones 1 and 2 Flashcards
What do you need to include in your description of fractures?
- Location: Diaphyseal, physeal, articular
- Orientation: Transverse, oblique, spiral
- Displacement: Distal segment relative to proximal
- Comminuted?
o This means multiple fragments - Open/closed?
o This is part of both the physical exam and radiography (is there gas in the soft tissue?)
How would you describe this image?
Mid and distal diaphysis of the tibia with cranial lateral and proximal displacement, it is comminuted and it does not appear to be open
How long does it take to see a periosteal response radiographically?
8-10 days
What are the 4 A’s of fracture repair?
Alignment, apposition, apparatus and activity
Which complication of fracture healing is this image demonstrating?
Non-union - this fracture is not healing and there is no evidence of repair
What are the main reasons for non-union?
- Atrophic (avascular) - limited/no vascular supply to support repair
- Hypertrophic - Lots of repair but can occur when the fracture is not immobilised
Which complication of fracture healing is this image demonstrating?
Malunion
Which complication of fracture healing is this image demonstrating?
Osteomyelitis
Do we expect to see differences in fracture repair in a puppy vs an adult dog?
Yes, younger animals are more able to heal fractures more rapidly
What would you expect to see in an aggressive bone lesion?
- Poorly demarcated
- Wide zone of transition
- Poorly marginated osteolysis
- Cortex interrupted
- Interrupted irregular periosteal reaction
- No surrounding sclerosis
- Rapid rate of change
Give some examples of aggressive bone lesions.
- Malignant neoplasia
- Primary bone tumours
- Metastatic bone lesions
- Round cell tumours
- Osteomyelitis
- Bacterial
- Fungal
Give some examples of aggressive bone lesions.
- Malignant neoplasia (Primary bone tumours, Metastatic bone lesions, Round cell tumours)
- Osteomyelitis (Bacterial, Fungal)
What would you expect to see in an NON-aggressive bone lesion?
- Well demarcated
- Narrow zone of transition
- Absent or geographic osteolysis
- Cortex may be displaced, remodelled and thin, but not broken
- Solid, smooth periosteal reaction
- +/- Surrounding sclerosis
- Static or slow rate of change
Give some examples of NON-aggressive bone lesions.
- Benign neoplasia (Osteoma, Chondroma, Osteochondroma, Multiple cartilaginous exostosis)
- Bone cysts
What factors affect fracture healing?
- Vascularity
- Fracture site
- Fracture type
- Fracture reduction
- fracture motion
- age and general health
What are the types outlined in the salter-harris classificaiton of bone fractures?
- Type 1 - goes straight through the open growth centre
- Type 2 - through the physis and exit the metaphysis, no articular involvement
- Type 3 - usually articular goes through the epiphysis and goes straight out the physis (rare)
- Type 4 - Articular fracture, goes through epiphysis, involves the physis, exits through the metaphysis
- Type 5 - Crush injury to the physis
What is the difference between mono-ostotic and poly-ostotic (both localised and generalised)?
- Mono-osmotic - one bone affected
- Poly-osmotic localised - multiple bones affected, but within the same region
- Poly-ostotic generalised - multiple bones affected, seen in more than one region in the skeleton
What are the types of primary malignant bone tumours?
- Osteosarcoma
- Chrondrosarcoma
- Fibrosarcoma
- Haemangiosarcoma
- Liposarcoma
Desribe the common features of primary malignant bone tumours.
- Mixed lytic and productive
- long zone of transition
- mono-ostotic
Desribe the common features of metastatic bone tumours.
o Highly lytic
o Long zone of transition
o Poly-ostotic, generalised
Desribe the common features of osteomyelitits.
- Primarily productive
- long zone of transition
- mono-ostotic
- poly-ostotic (generalised and or localised)
What are we looking at here?
Osteoarthrosis - Irregular new bone formation
What are we expecting to see in degenerative bone disorders?
Generally purely productive
- Periarticular new bone formation
- Subchondral bone sclerosis
- Soft tissue mineralization
What types of bone disorders are younger animals likely to develop?
- Developmental abnormalities such as dysplasia (eg. elbow or hip)
- This usually results in degenerative joint disease
Where are you most likely going to see osteochondrosis?
- Medial humeral condyle (distal)
- caudal humeral head
- Lateral and medial trochlear ridges
- lateral and medial femoral condyle
- vertebral articular facets
Explain hip dysplasia
- Coxofemoral joint subluxation
- Poor coverage of the femoral heads by acetabulea
- Poor joint congruity
- Osteoathrosis will develop - important to determine the cause. If it is a result of hip dysplasia, then we want to not breed these animals.
What do we expect to see in septic arthritis?
- Joint effusion
- With or without subchondral erosion
- Often occurs in joints with substantial arthritis
- SEVERE pain
