Final: Fracture fixation- pins, ESF, screws, plates, interlocking nails Flashcards
Which of the following is not a commonly used descriptor for fractures?
Displacement
Reparability
Communication with external environment
Reparability
What are the indications for external coaptation (closed reduction) of a fracture?
Below elbow or stifle
Bone will be stable after reduction
Fracture expected to heal quickly and without disease (i.e. young patient)
Small dogs or cats
E.g. Greenstick, Intact periosteal sleeve, Impaction fractures
What type of ESF is unilateral and uniplanar? What aspect of the tibia is this placed? Femur? Humerus? Radius?
Type 1A
Tibia= Medial
Femur, Humerus= Lateral (usually w/IM pin)
Radius= Cranial and medial
How long does an oblique fracture have to be for it to be considered ‘long’?
>2 x diameter of bone
Under which forces is an oblique fracture stable and unstable?
Unstable in compression
Less unstable than transverse in bending, rotation
Stable in torsion
What classification of open fracture involves a lot fo soft tissue trauma but with enough tissue for closure?
Type 3A
Classify this fracture
Simple mid-diaphyseal transverse fracture of the femur
What are postitive profile threaded pins?
The threads of the pins stick out beyond the core/base of the pin
What are the indications for full cerclage wire? When is the use counterindicated?
Long oblique or spiral fractures (fx line at least 2x bone diameter)
C/O’d: Short oblique fractres, fractures with more than 3 segments, unreducible fractures
What functions do these plates serve?
A= Compression
B= Neutralization
C= Holding collpased epithysis in position
What are advantages and disadvantages of closed reduction?
(+): Preserves soft tissue and blood supply, less risk of infection, decreased operating time
(-): Difficult to obtain accurate reduction
What types of fractures can be compressed by a plate?
Transverse
Nearly transverse
Any other type will shear
In what fashion must interlocking pins be placed? What type of fracture can they be used for? What forces do they resist?
Normograde
Mid-diaphyseal fractures of humerus, femur and tibia
Resist bending, shearing and rotation
3 or more pieces upgrades a simple fracture to a _____ fracture.
Comminuted
What is the most common cause of fractures in small animals?
HBC
T/F: The Salter Harris fracture classification system can only be used in the bones of young patients.
True
What type of plate is used here?
Bridging (Buttress)
What are the 3 methods to obtain fragment apposition and potentially compression of a short oblique fracture?
Lag screws
Skewer pin
Hemicerclage wire
In addition to something else, not alone!
What complication fo you risk if you were to place an ESF into the humeral diaphysis blindly?
Nerve or vessel damage (Specifically the radial nerve)
Which is why you don’t do that
T/F: ESF can only be used for open fractures.
False
What type of fixation is ideal for this situation?
Interlocking pins
What type of plate is this?
LC-DCP
Which type of plate as a neutralizing or bridging application but does nnot compress a fracture? What is it often combined with?
String of Pearls
Rods/IM pin
What type of pin is a Steinmann pin?
Intramedullary
What classification of open fracture involves exposed bone and stripped periosteum but no damage to arterial blood supply?
Type 3B
What type of plate can you place on an oblique or comminuted fracture?
Neutralizing plate
All screws neutrally positioned and same diameter
Does compressing a fracture using a bone plate stimulate bone healing and provide osteoinduction?
No
It provides a stable mechanical environment
_______ fractures go in the same direction as the long axis of the bone.
Fissure
What type(s) of plate(s) can be used as an alterative to cross pinning in some fractures?
L or T plates
What are advantages to open fracture reduction? Disadvantages?
Direct visualization of the fracture to facilitate reconstruction
Allows placement of implant
Allows load sharing
Bone grafts
(-): Increased surgical time, increased soft tissue trauma and compromised blood supply, increased risk of infection
What type of fracture is this? Does it require surgical repair? If so what kind?
Greenstick or Incomplete
No, inherrently stable
What screws are meant to lock into a LCP?
Locking head screw
LCP= locking compression plate
On which bones can a tyoe 2 ESF be placed? On which bones is it counterindicated?
Radius and tibia (medial to lateral)
Cannot use on femur or humerus (no room to go through whole bone due to axilla or groin)
Which type of Salter Harris fracture can cause angular deformities because it can result in the eventual cessation of physeal function (which may not be radiographically evident immediatly)?
Type V (5)
Which of the most commonly used bone screws has a larger pitch and deeper thread? What type of bone are these for?
Cancellous
Metaphyseal or epiphyseal bone (softer bone)
What classification of open fracture involves an external object having penetrates soft tissue with mild soft tissue trauma?
Type 2
What is stack pinning? Does it imporve the resistance to bending forces?
2 or more IM pins used to fill medullary cavity
No advantage found
If a fracture runs through the physis and a portion of the metaphysis what Salter Harris classificaiton is it?
Type II (2)