25: Fractures

First thing to do when a patient comes in for a fracture

Treat the patient first! It is likely from trauma, and the fracture can wait

Radiographs to take if a patient presents for a traumatic event and you suspect a fracture

• 2 views where you suspect the fracture

• Check the thorax!!

Why do we need oblique views of the distal limb when evaluating fractures

You will only see the fracture if you are in the plane of view, and they can easily hide in the distal limb

Normal anatomic variations that may mimic a fracture line

• Superimposed ST

• Nutrient foramen

• Heel crack (ungulates)

Location of the nutrient foramen

In the cortex of the proximal diaphysis in long bones

List the 7 descriptors for bone fractures

1. ST changes: open or closed, swelling

2. Complete or incomplete

3. Simple or comminuted

4. Traumatic or pathologic

5. Configuration

6. Displacement

7. Acute or chronic

Why do we care if a fracture is open or closed

Open fractures are or were open to the outside world, and there is an increased risk of infection

Radiographic findings associated with an open fracture

Gas in ST or penetrating debris

Typical cause of diffuse ST swelling

Fluid (edema, hemorrhage, etc.)

Incomplete fracture

Fracture line does not cross from cortex to cortex

Complete fracture

Fracture line crosses from one cortex to the other cortex

Common signalment for an incomplete fracture

Young animals; immature bones are flexible → greenstick fracture

Fissure line

Smaller fracture line extending from the main fracture line

Simple fracture

One line is splitting a bone into two pieces

Comminuted fracture

Lots of lines, lots of bone pieces

Pathologic fracture

The bone was not normal prior to the fracture, and broke in response to what might have been a normal amount of stress to the bone

Why do we care to differentiate between traumatic and pathologic fractures

Informs whether and how to treat

List the fracture configurations

• Transverse

• Oblique

• Spiral

• Segmental (>1 piece)

Common location for a spiral fracture

Tibia

How is displacement described

How the distal segment of the fracture moved from normal

Radiographic indicators of an acute fracture

Sharp edges with no new bone

Radiographic indicators of a chronic fracture

Rounded edges with periosteal new bone (callus), fracture gap may be increased due to healing processes

Common type of fracture involving the flat bones of the skull

Depression fracture

Common type of fracture involving the spine

Compression fracture

Avulsion fracture

Fracture at the site of soft tissue attachment (enthesis) 

Enthesophyte

Periarticular new bone at site of ST attachment

Common site of avulsion fracture

Apophyses

Common types of fractures in the carpal and tarsal bones

Chip fractures and slab fractures

Alternate name for physeal fractures

Salter-Harris fracture

Patient demographic for physeal fractures

Juvenile patients with open physes

Type 1 physeal fracture

Physeal fracture separating metaphysis and epiphysis

Type 2 physeal fracture

Fracture running through physis and metaphysis

Type 3 physeal fracture

Fracture running through the physis and epiphysis

Type 4 physeal fracture

Combo of 2 and 3, runs from metaphysis through the physis and out the epiphysis

Type 5 physeal fracture

Crushing fracture, prematurely closing the physis

Most common type of Salter-Harris fracture in vet med

Type 2

Hardest physeal fracture to diagnose

Type 5

Most common physeal fracture at the distal humerus

Type 4

Most common site of type 5 fracture and why

Distal ulna because the physis is V shaped

Consequence of a Type 5 physeal fracture at the ulna

Stunted ulnar growth with continued radial growth → cranial bowing of radius

Consequence of a cranially bowed radius

Increased risk of elbow dysplasia

Montagia fracture

Fracture with accompanying luxation