Fracture repairs Flashcards
What counteracts all forces and can be contoured to the shape of the bone?
Bone plates
Dynamic compression plates aka DCP plates-
Oval shaped screw holes, can be used to compress the fracture, screws may be placed neutrally and DO NOT compress
Screwing in middle of the holes means neutral, lack of compression
Offset of the holes means more compression
DCP plates promote ____ healing
primary
______ plates have limited contact between the bone and plate and easier to contour the plate.
LC-DCP
How do LC-DCP plates avoid obstruction of bf??
by decreasing the contact between bone and plate
What are the three types of plates?
Compression plates, locking plates, specialty plates
What is the ORIF technique? What is its goal?
Open Reduction with Internal Fixation
primary goal is primary bone healing! Most stable form of repair but causes more damage to the bf and soft tissue surrounding the bone
MIPO aka Minimally Invasive Plate Osteosynthesis- Goal is to….
goal is to stabilize and align the fracture without disrupting the bf
Align joint and preserve the length of bone
Open but do not touch principle-
Open repair of fracture with minimal incision, fracture site hematoma is not disrupted and still allows for anatomic alignment with plate placed across the bone
Avoid disrupting bf and hematoma
Best of both world if able to do it
We need ___ screws above and ___ screws below. Be sure to make ___ cortices min with DCP plates.
___ cortices min. with locking plates
3;3;6 with DCP plates; 5 min with locking plates
Plate placement- plate should be placed on side with greatest _____ to overcome bending. where is this not the case?
tension; except in femur where the tension is cranial but the plate is on the lateral side due to soft tissues
where to put the plate in the…
- Radius
- Tibia
- Humerus
- Radius- dorsal
- Tibia- medial
- Humerus- lateral
Avoid placing screws towards the _____ ____
fracture line
____ and ____ screws are based on the type of bone, locking vs. nonlocking heads.
cortical and cancellous screws
___ screw is not a type of screw, it is a type of positioning of the screw.
Lag
Near side aka ____ _____ is where the hole matches the OUTER diameter of the screw
CIS CORTEX
Far side aka ___ ____ is where the hole matches the shaft diameter of the screw
TRANS CORTEX
What form of plating is where the bone does not bear the weight, walking on their plate.
Buttress aka bridging
When do we use Buttress aka bridging? What is our goal?
Too much of a gap in the bone. We have to rely on callus formation without primary bone healing and our goal is to maintain bone length!!!
What method of plating is where implant shares the load with the bone and does not compress the fracture. Bone is not bearing full weight, relies on callus formation without primary bone healing.
Neutralization
String of pearls (SOP_ plate is rounded with larger holes, best for ____
Contouring to the bone
Why cant we only use a pin by itself?
NEVERR use a pin by itself because they can only prevent bending and shearing, but NOT strong, and does not work against torsion or compression
Normograde insertion of pins vs. retrograde insertion of pins:
Normograde- fracture is reduced, pin is driven down into bone, across fracture and into opposite bone segment
Retrograde is where pin is driven up trough the distal portion of the fragment- fracture is reduced- pin is driven across the fracture and seated in the opposite (proximal) segment
Kirchner aka K wires are similar to _____ pins but not as strong
Steinmann
Interlocking nails are very strong and can be placed with minimal invasiveness. What are the pros and cons?
Pros- can be placed minimally invasively in some bones, does not damage hematoma
Cons- thick so impacts bone supply in the medullary cavity
Fracture line must be ____ x the diameter of the bone to use full cerclage wire**
More than 2x
**Full cerclage wires should be spaced ____ cm apart and ___ cm from end of fracture lines. Must be min of ___ wires
about 1cm; 0.5cm; 2 wires
For full cerclage wires– Wires are placed _____ to long axis of bone shaft
Perpendicular
Tie in configuration is used when there is fracture of what two bones?
femur or humerus
ESF clamped into IM pin in the bone is called
Tie-in configuration
circular fixators (CESF) are when we use small wires as _____ pins
transfixation
When do we use circular fixators (CESF)
Fracture fixation, limb lengthening, angular limb deformity correction
Hybrid fixations (components of both CESF and linear ESF) makes use of ___ and ____ compartments
linear and circular;
Criteria for sx of pelvic fx:
Articular fracture (acetabulum), weight bearing axis (ilial body fx, or SI luxation), marked decrease in pelvic canal
What is the most common pelvic fracture and how do we repair it?
Ilial body fx, repair with plate and screws
SI luxation repair involves __ screw placement
Lag screw
____ fractures are usually concurrent damage to femoral head cartilage, joint surface must be reconstructed, likely to result in long term arthritis
Acetabular
When is it okay to do without sx for pelvic sx?
If only CAUDAL (non weight bearing) part is affected-
Physeal fractures usually occur in patients less than ___ years old.
1 year
During physeal fracture, damage to growth plates may result in ___ ____ or limb shortening
angular deformities
The process by which growing cartilage is systemically replaced by bone is called ______ _____
Endochondral ossification
Stabilization of spinal fx requires surgical fixation with ____ ____
internal fixation
What are the 4 A’s of fracture assessment*?
Alignment, Apposition, Apparatus, Activity
Must have more than ___% apposition for healing
50%
____ is the assessment of the surgical implants themselves and how they are placed and if they are the right size
Apparatus
Activity is the bone healing process in terms of..
function maintained and is assessed using pre-op, post-op and follow up rads
Neuropraxia nerve damage-
short term, temporary neuro deficiencies, with inflammation that resolves on its own
Nerve damaged from increased pressure in the muscle….
aka “compartment syndrome” which is common around the femur where it puts pressure on the nerve
What are some possible joint complications?
decreased range of motion- loss of mobility in the joint, called “ankylosis”
soft tissues of delayed/non-union include decreased bf in distal antebrachium usually in small dogs. Most common location is the ?
Distal radius
Involucrum definition:
Periosteal new bone surrounding the sequestrum, may look sclerotic on rads
