Pins And Wires Flashcards
Steinmann pins are AKA?>
Intramedullary pins
T/F: steinmann pins can be smooth or threaded
True
Small steinmann pins are AKA?
Kirschner (k) wires
Advantages of steinmann pins?
Inexpensive Small inventory Less tissue trauma Less surgical time Easy to remove
Can are disadvantages of steinmann pins?
Cannot maintain bone length
ONLY resists bending forces
Pin migration
What are all the possible applications of steinmann pin applications?
Intramedullary placement Stack pinning Cross pinning Rush pinning Diverging pins Skewer pin
T/F: intramedullary pins are an adequate fixation method on their own
False
Always need adjunct
Eg cerclage wire, ESF, or plate
How can you place a intramedullary pin ?
With Jacobs chuck or pin driver
Normograde or retrograde
IM pin placement is contraindicated in what bone?
Radius
Indications for IM pins?
Small dog or cat with stable/simple fracture
When is IM pin contraindicated?
Most fractures in medium and large dogs— too much force
T/F: stack pinning (2 or more pins to fill the medullary cavity) provides more fracture fixation
False
Clinically has shown no advantage and has higher incidence of pin migration
When cross pinning, the pins should cross on which side of the fracture
Larger side
Cross pinning is able to counteract which forces?
Rotational and bending forces
When is cross pinning used?
Physeal fractures
What type of IM pinning is used for very distal or proximal fractures and provides 3 points of contact ?
Rush pinning
What type of pinning method is used to stabilize salter harris 1 fractures of proximal humerus and femur?
Diverging pin
3 K wires are placed in triangular fashion (do NOT penetrate joint surface)
What are the uses of orthopedic wire?
Full cerclage Hemicerclage Skewer pin Tension band Interfragmentary wire
When if full cerclage wire used?
Long oblique or spiral fractures in which the fracture line is at least 2x the diameter of the bone
What is the maximum number of fracture segments that you can use full cerclage wire with?
3
When is hemicerclage wire indicated?
Short oblique diaphyseal fractures
Hole drilled in proximal and distal fracture segment
T/F: hemicerclage wire only counteracts rotation in one direction
True
What fracture fixation method uses a full cerclage wire that is placed around a K-wire that bisects a fracture at a perpendicular axis
Skewer pin
When is the skewer pin method indicated
Short oblique fractures
What type of fixation method is indicated for avulsion fractures?
Tension band wires
When can interfragmentary wires be used?
Simple fractures of flat, non weight bearing bones that interdigitate well
Eg certain mandibular and maxillary fractures
T/F: external skeletal fixators resist all forces?
True
When placing external fixator, you need at least _____ pins per fracture segment
2
When placing a type Ia fixator on the tibia, which side of the limb is it placed on?
Medial
When placing a type 1a fixator in a radius, which side of limb is it placed on?
Cranial and medial
When placing a type 1a fixator on the femur or humerus, which side of the limb is it placed on/
Lateral
What is a type1b external fixator?
Unilateral -biplanar
When placing a type 2 fixator on the humerus, what side is it placed?
None.. cannot place type 2 fixators on the humerus or the femur
Only on tibia and radius - these will be placed medial to lateral
What are the indications for a circular/ring fixator?
Complex fractures
Limb shortening/lengthening procedure
Angular deformities
Transport of bone segments
Complications to external skeletal fixation?
Loosing pins or wires
Delayed or non union fractures
Osteomyelitis
Loss of joint motion
Nerve or vessel damage
