Exam 2: Lecture 13: Fractures of the Pelvic Limb II Flashcards
What is the most common fracture you will see in the clinic?
tibial fractures
What are the 3 areas in which you will see tibial and fibular fractures
diaphyseal
metaphyseal
physeal
What does this image show?
Tibular and Fibular fractures
How do tibial and fibular diaphyseal fractures occur
from trauma to rear limb
Tibial and fibular fractures cause a disruption of diaphyseal _______ _______
cortical bone
Open fractures may occur with Tibial and fibular fractures. Why is this a concern?
sparese (low amount) of tissue coverage for wounds through the skin over the bone
Tibial and fibular fractures are primarily from trauma. What are some general causes?
- HBC
- gunshot
- fights with other animals
- falls
While the fibula is usually fractures it is seldom stabilized. When would be stabilize this bone?
When the stability of the stifle or hock is threatened
What is the primary pathologic condition that predisposes animals to Tibial and fibular fractures
skeletal tumors
The tibia is subject to several mechanical forces. Forces that act on these bones include?
- avulsion fractures
- transverse
- oblique
- spiral
- comminuted
- severly comminuted
How does paucity of soft tissue around the tibia and fibular affect fractures?
- increase potential for open fractures
- potentially decreases extraosseous blood supply
How is the paucity of soft tissue around the tibia and fibula and adcantage for placing an external fixator (ESF)
- because you can place the external support / fixator knowing it will be removed later on
- Does not promote infection due to the metal implants being removed
Minimal soft tissue coverage of bone plates results in?
- tissue irritation
- cold hypersensitivity
Tibial fractures mostly occur due to?
trauma
Since tibial fractures are mostly from trauma what must be accessed?
- entire animal must be evaluated for concurrent injuries
concurrent injuries from an animal with tibial fractures may include?
- pulmonary contusions
- pneumothroax
- rib fractures
- traumatic myocarditis
Concurrent injuries to the limb with tibial fractures may include/caue what to happen to the leg?
extensive soft tissue damage or loss
What is the signalment for animals with Tibial and fibular fractures
- any age, breed, or sex
- dog or cat
- young animals most likely from HBC
What history does an animal present with in Tibial and fibular fractures
- NWB lameness after truma
- owners may be unaware that trauma occured
What might be present on a PE in a animal with Tibial and fibular fractures
- NWB on affected limb
- palpable swelling
- crepitation and pain at fracture site
- fracture may be open with or without soft tissue loss
-
may have abnormal propioceptive responses
(reluctant to move limb from pain)
An animal with Tibial and fibular fractures may have abnormal proprioceptive responses during the PE, why?
reluctant to move limb from pain
Animals needed craniocadual and lateral radiographs for Tibial and fibular fractures. If pain is present, what options do I have to get proper positioning and good quality radiographs
sedation or general anesthesia
Radiographs can be taken under anesthesia just before surgery, but what issues does this cause
reduces the time available for plannig surgical repair
What are the 3 benefits for radiographs on the contralateral limb for Tibial and fibular fractures
- useful in assessing normal bone length and shape
- used to contour bone plate more precisely before surgery = reducing operative time
- reference to select appropriately sized implants
What labatory finding would be on an animal with Tibial and fibular fractures
- no consistent lab findings
- animals sustaining fractures secondary to trauma
(need suffiicient blood work done to determine appropiate anesthesic regimens + concurrent
Diagnosis of tibial fractures are based on what two things?
- PE
- radiographic examination
Animals with Tibial and fibular fractures need to be evaluated to determine if the fractures are results of truam of underlying pathologic conditions such as?
neoplasia or metabolic (bone) diseases
When are antibiotics ok to be given with Tibial and fibular open fractures
after culturing
Conservative fractures can be used for what type of fractures?
diaphyseal fractures
Splints and casts (conservative fractures) can be used for what type of (diaphyseal) fractures?
closed
nondisplaced
greenstick fractures
immature animals
Why are casts / splints an appropiate fixation for Tibial and fibular fractures
because the fractured bone (stifle and hock) can be immobilized
Where would you place a cast/splint for Tibial and fibular fractures
joint above and below fractures bone (stifle + hock) can be immobilized
Can a cast / splint be used on the femur
HECK NO
With a cast/splint the fracture should heal rapidly, but what consideration has to be taken in account
If the animal can/will bear weight on the other 3 limbs
Decisions to perfrom an open or closed reduction of the tibial diaphyseal fracture is made on the basis of what 3 “things”
- fracture configuration
- fracture assessment score (FAS)
- implant needed
If an open reduction if the fractured tibia is performed what is used to enhance bone healing
BONE GRAFT
Accessible site for cancellous bone harvest are?
- ipsilateral proximal humerus
- wing of the ileum on the same limb
- ipsilateral distal femur
What type of Fixations systems are available for tibial diaphysis
- casts
- IM pnis with cerclage wire or ESF support
- interlocking nails
- ESF (linear, circular or hybrid)
- bone plates
Implant systems should reflect _______ score
FAS
Would the following scenero call for a open, limited open or closed reduction?
- displaced reducible fractures with internal fixation
open reduction
Would the following scenero call for a open, limited open or closed reduction?
- displaced reduicible fratures with external skeletal fixation
limited open reduction
Would the following scenero call for a open, limited open or closed reduction?
- comminuted fractures neccessitating cancellous bone graft
limited open reduction
Would the following scenero call for a open, limited open or closed reduction?
- nondisplaced fracture with external coaptation or external skeletal fixation
closed reduction
Would the following scenero call for a open, limited open or closed reduction?
- comminuted nonreducible fractures with external skeletal fixation
closed reduction
How should open wound be managed initally?
- carefully clipping surrounding hair
- cleaning wound
- obtaining swab for bacteria C+S testing
- CULTURES FOR OPEN WOUNDS OBTAINED BEFORE ANTIBIOTICS ADMINISTERED
What is a trick that can be used to prevent hair and other debris from entering the open wound
A ton of KY jelly in the wound to prevent contamination
What type of fracture management is shown in this image?
Robert jones bandage
How would temporary stabilization of the limb with robert jones bandage be beneficial?
- immobilize fragements
- decrease or prevent soft tissue swelling
- protect or prevent open wounds
- enhance patient comfort until surgery performed
What preoperative management would be indicated with open reduction of tibial or fibular fracture is performed
prophylactic antiobiotics
Peroperative management of tibial and fibular fractures should include?
- analgesics provided to posttraumatic animals
- concurrent injuries managed before animal is anesthesized for fracture fixation
- prophylatic antibiotcs indicated when open reduction is performed
What type of reduction does this image show?
indirect reduction
- because you are not doing the work, the animals weight is moving the bones in correct placement
- animal positioned with affected leg suspended from ceiling
During a closed reduction or limited open reduction how is the leg prepped and why would you position the affected leg suspended from the ceiling
- Leg preped hip to below hock
- To improve visualization of correct joint alignment
If you are harvesting a cancellous bone graft for a closed reduced or limited open reduction procedure, what is important to keep in mind regarding te donor site?
donor site should be prepared
Can a open reduction / plate application be performed with the leg suspended?
it can!
How would you position an animal with IM pin or interlocking nail application
animal positioned in dorsal recumbency
- limb draped out and released to expose medial surface
(leg is not suspended)
Casts are used to stabilize closed nondisplaced tib-fibfractures in animals with what FAS score
FAS of 8-10
What does A show?
full cylinder cast
What is the purpose of this full cylinder cast
- immobilizes stifle + hock
- Placed with limb in sight extension + varus angulation
What does B show?
Cast bivalved
What is the purpose of the cast bivalved
- apply cast material over multiple layers of padding
- cut lateral + medial aspects
- secure 2 halves around the limb with elastic tape
IM pins used to stabalize tibial diaphysis fractures provide excellent resistance to ?
provide excellent resistance to bending
IM pins used to stabilize tibial diaphysis fractures provide no resistance to?
rotational forces or axial bending
If you use IM pins additional implants should be used to provide what type of support for the fracture
rotational + axial support for the fractures
Transverse or short oblique fractures treated with IM pins require unilateral ESF splint to control?
control rotation
In spiral or oblique fractures where the length of fracture line is 2-3 times diaphyseal diameter what technique should be used for stabilization?
IM pins + multiple cerclage wires
What does A show?
transverse or short oblique fractures stabilized with intramedually (IM) pins + unilateral ESF
What does B show?
Spiral or oblique fractures treated with IM pins + multiple cerclage wires
What does C show?
Interlocking nail for nonreducible fractures
- only place you cant use is the radius - JUST SAY NO!!
Where is the ONLY place you can NOT use interlocking nails for a fracture that is non-reducible?
the radius
Correct placement of IM pin is critical to avoid interfacing with which joint
stifle joint
What type of pinning risk the damage to intra-articular structures in dogs and patellar ligaments in cats
- JUST SAY NO!
retrograde
Retrograde pinning risk damage to what area of the dog and which area of the cat
intra-articular strucutres in the dog
- patella
patellar ligament in cats
How can we estimate appropiate pin penetration length into the distal bone segment
A 2nd pin equal in length to one in marrow cavity for point of reference
If and ESF used with IM pins the pin small enough should be used so that fixation pins can be placed through which areas?
Tibial diaphysis
We must estimate the size of IM from pre-op radiograph. What size pins may be needed for curve of the tibia
smaller pins
How must pins be placed in starting at the proximal end of the tibia
- manipulate hock to ensure pin does not interfere with joint
normograde manner
Pins must be placed in normograde manner starting at the proximal tibia. Which area can be manipulated to ensure the IM pin does NOT interfere with the joint
manipulate the hock
For normograde IM pin placement you insert the pin medial aspect of proximal end of tibia.
- Penetrate bone midway from ____ and ____ on the medial ridge of tibial plateau
midway between tibial tubercle and medial tibial condyle
After you insert the IM pin in the medial aspect of the proximal end of tibia, what must be done afterwards?
- drive fown medullary canal to exit at fracture
- reduce fracture and drive pin distally
- seat pin into distal bone segment (stop before penetrating articular surface)
Correct normograde placement of the IM pin inserts through skin on medial aspect of proximal tibia
- The IM pin should penetrate the bone between which two areas on the medial ridge of the tibial plateau?
Midway between tibial tubercle and medial tibial condyle
What is #1
patellar ligament
What is #2
medial collateral ligament
What is the *
IM pin placement
What type of ESF is A?
Type I ESF
- on craniomedial surface of tibia to stabilize transverse fracture
What type of ESF is B?
Anatomic reconstruction of long oblique fracture with cerclage wire
- restores bony column + allows load sharing with Type Ib ESF
What 2 types of ESF are used to treat tibial fractures in patients with high + moderate FAS
Type Ia and Ib
Is A or B type Ib ESF
B
Is A or B type I ESF?
A
What type of ESF is C?
Minimal type II
- frame constructed with unilateral fixation to fill out pins
What type of ESF is used to treat patients with a low FAS?
type II - minimal / maximal
If all the pins in this image went through the entire bone to the other side, what kind of Type II ESF would this be?
maximal type II
The following technique is used to treat what type of deformity of the Tibia?
A. Loosen clamps distal to fracture
- reposition distal segment
= move clamps distally on lateral bar + proximally on medial bar until joints parallel
= reverse procedure to correct varus angulation
A. when joints aligned tighten clamps
Correct Valgus angulation of the tibia
What does this diagram show?
Correction of valgus angulation of Tibia
What does A show?
Compression plate
- for transvere fractures
What does B show?
Neutralization plate
- support long oblqiue fractures reconstructed with lag screws
What type of plates are used for transverse fractures
compression plate
- A
What type of plates are used to support long oblique fractures with lag screws
neutralization plate
- B
Compression / neutralization / bridging plates are placed on which side of the tibia?
medial surface
What types of plates are used with or without IM pins to span non-reducible fractures
Bridging plate
- with plate-rod construction
What type of plate is shown by C and D?
Bridging plate
- With or without IM pin to span non-reducible fracture
Contouring plate
- to match normal configuration of tibial essential
Failure to reproduce normal curve of the tibia can result in?
valgus or varus angulation of the limb
Methods for stabilizing transverse or short oblique tibial fractures is based on?
FAS score
These fixations would be used for what type of fractures
Transverse or short oblique
Which of the following fixators would be used for older animals and why?
Far left would be used
- they need more rigid fixation
Which of the following fixators would be used for younger animals and why?
two on the farthest right
- less rigid fixation is needed
Methods for stabilizing long oblique or reducible comminuted tibial fractures is based on?
FAS score
These methods of stabilization are used in what type of fractures
long oblique or reducible comminuted
Which of the following stabilization methods would be used for younger animals
Far right
- less rigid fixation needed
Which of the following would be used for older animals
left
- rigid fixation is needed
These methods of stabilization can be used for which tibial fractures based on FAS
nonreducible comminuted
Complications of tibial and fibular diaphyseal fractures are?
- osteomyelitis
- implant migration
- malunion
- delayed union
- nonunion
Complications with ESF of the tibia include pin loosening and ?
pin tract drainage
What is the most common reason for complications in tibial and fibular diaphyseal fractures
poor decision making with implant choice
Cats treated with rigid ESF may be at risk for what type of complications?
delayed healing
nonunion
What is the prognosis of tibial and fibular diaphyseal fractures after tibial fracture repairs
generally good
- if proper fracture management procedures are followed
Fractures of proximal tibial metaphysis and epiphysis occur frequently in mature dogs + cats. Usually these fractures are** transverse or short oblique**
- These fractures may be ________ due to severe trauma or gun shot
comminuted
Fractures of the distal tibia in mature animals usually involve which structure?
malleoli
Fractures of the malleoli + erosion injuries that remove the malleoli result in loss of malleaolar stability, resulting in?
- loss of collateral ligament functions
- Talocrural instability
Accurate alignment of articular surface of malleolar fractures and rigid fixation is needed to achieve joint stability + minimize development of which disease
DJD
Simple single fractures of proximal tibial metaphysis in dogs with high or low FAS
- stabilized with IM pin
high FAS score
What does A show?
K-wire + figure 8 wire
- added for rotational stability
What does B show?
Crossed K-wire (may be used)
What does A and B show?
Fracture of tibial + fibular malleoli repaired with lag screws
What does C show?
Tension band wire in patients with high FAS score
What is #1
lateral Malleous
What is #2
Medial Malleous
What is #3
Glide hole made for the lag screws
What is the prognosis for for metaphyseal fractures
they heal quickly - good?
Why do metaphyseal fractures heal quickly
due to the large amount of cancellous bone around fractures
What part of the bone has good/large amounts of cancellous bone
- which is beneficial for quick bone healing
metaphysis and diaphysis
Trabecular bones heals with minimal formation of?
callus
Where are physeal fractures common in immature animals?
through cartilaginous growth plate of proximal or distal tibia or tibial tuberosity
What are other names for physeal fractures that occur through cartilagninous growth plates of proximal or distal tibia or tibial tuberosity in immature animals
- epiphyseal plate
- slipped physes
Cartilaginoius physis is weaker than surrounding bone and ligaments which can lead to?
more susceptible to injury
T/F: Tibial fractures may be displaced
true
Salter-Harris classifications categorize physeal fractures based on?
- basis of radiographs
- histologic presence
Which level / category of Salter-Harris is described below?
- Proximal tibial physeal fractures
usually salter I or II fracture
- rare to be a salter III of IV fracture
Which level / category of Salter-Harris is described below?
Fractures of the Fibula
- Epiphysis may be displaced caudolatera to tibial diaphysis
- additional injury to collateral ligaments may occurs
Salter I or II fractures
What typical treatments are usually required to restore normal anatomy in animals with tibial + fibular physeal fractures
open reduction
internal fixation
Which level / category of Salter-Harris is described below?
- Distal tibial physeal fractures
usually Salter I or II fractures
Using DI for Tibial and Fibular fractures with minimally displaced fractures may be difficult to determine if normally radiolucent physis is fractures. How can you check?
Comparison radiographs of opposite limb often beneficial
Using DI for Tibial and Fibular fractures with minimally displaced fractures may be difficult to determine if normally radiolucent physis is fractures. Comparison radiographs of opposite limb often beneficial to help with diagnosis. This is particulary important in animals with what type of avulsions
Tibial tuberosity avulation
- sometimes they look like a fracture and othertimes they do not so good to Xray other limb to check for symmetry
Radiographs at the time of injury do NOT provide information about crushing injuries to physis or damage to physeal blood supply. What can be said about prognosis at time of injury
Difficult to give an accurate prognosis for growth with these fractures at time of injury
What FAS score would you give most physeal fractures?
FAS 8 to 10
Most physeal fractures are classified as FAS score of 8 to 10. Why would this be the case in young animals
physeal fractures heal quickly
Implant systems do not need to function for a long term in Tibial and Fibular Physeal Fractures. So what types of surgical treatment can be used for these displaced physeal fractures?
- Anatomic reduction and stabilization with K-wires or small pins
- Use smooth pins
(So they do not interfere with physeal function)
For surgical treatment of tibial and fibular fractures why would you place the pins at a 90 degree angle
allows growth more than pins places obliquely + anchored in cortical bone (cross-pinning technique)
For surgical treatment of tibial and fibular fractures how would you treat animals closer to maturity
threaded implants may be used to compress fixed physis
What type of implants should be used when crossing the physis in animals with potential growth
smooth implants
Displaced tibial physeal fractures are treated with open reduction and placement of?
K-wires
What does this image show?
Displaced tibial fractures treated with open reduction and placement of crossed K wires
Fractures through physis of tibial tubersotiy results in proximal displacement of?
tibial tuberosity
Fractures through physis of tibial tuberosity results in proximal disaplcement of tuberosity. These fractures must be reduced and stabilized to restore what muscle functions and stifle extension
Restore quadricpets muscle + stifle extension
Avulsions of the tibial tuberosity should be reduced and stabilized using?
2 K-wires
If displacement of fragments occur with fracture of tibial tuberosity when the stifle is flexed What pattern of qire may be added in large breeds
Figure 9 orthopedic wire
What does the figure on the left show?
Avulsion of tibial tuberosity reduced and stabilized with 2 K-wires
What does the figure on the right show?
Displacement of fragments occurs when the stifle is flexed
- figure 8 orthopedic wire added in large breed dogs
What is the prognosis for healing of physeal fractures
excellent
What is the prognosis for continued function or growth of the physis
depends on the amount of damage sustained by zone of proliferating cells
What is the prognosis for fractures that seperates physis at zone of hypertrophied cells
good for future physeal growth
What is the prognosis for fractures where the physis is crushed by trauma
poor for future physeal growth
Most trauma-induced physeal fractures sustain damage to growing cells have have ____ prognosis for growth
- maybe have angular limb deformities
guarded prognosis for growth
Premature closure of proximal or distal tibial physis usually results in?
short but straight limb
Premature closure of proximal or distal tibial physis usually results in short but straight limb. The animal compenstates for this by?
extending the stifle
Caudal malalignment of proximal tibial epiphysis may result in?
increased tibial plateau angle
Premature closure of tibial tuberosity physis can alter conformation of the proximal tibia leading to?
impaired function and stifle DJD
Caudal aligment of proximal tibial epiphysis may result in increased tibial plateau angle. How can this be check and what ligament would be damaged?
Can be checked by moving the tibia caudally. If over-extension occurs then the caudal cruciate ligament is ruptured
