Lecture 13: Fractures of the Pelvic Limb II (Exam 2)

Question 1

What can cause tibial & fibular fractures beside trauma

Answer 1

• Neoplasia
• Metabolic dx

Question 2

When can conservative management be used

Answer 2

• Diaphyseal fractures
• Casts/splints can be used for closed, nondisplaced, or greenstick fractures in immature animals

Question 3

Why is cast/splint fixation appropriate

Answer 3

• Joint above & below fractured bone (stifle & hock) can be immobilized
• Fracture should heal rapidly
• Consider if the animal will bear weight on the other 3 limbs

Question 4

Are bone grafts need if dealing w/ an open reduction of a fractured tibia

Answer 4

AC bone graft is indicated to enhance bone healing

Question 5

What fixation systems can be used for dibial diaphysis

Answer 5

• Casts
• IM pins w/ cerclage wire or ESF support
• Interlocking nails
• ESF
• Bone plate

Question 6

What should be done pre op

Answer 6

• Analgesics provided
• Concurrent injuries are managed
• Prophylactic antibiotics if there is an open wound

Question 7

What is the positioning of the limb w/ a closed or limited open reduction & ESF

Answer 7

• Prep hip to below the hock
• Donor site should be prepped

Question 8

What is the positioning of the limb w/ a open reduction & plate application

Answer 8

Can have the leg suspended

Question 9

What is the picture showing

Answer 9

Question 10

How do IM pins help stabilize tibial diaphyseal fractures

Answer 10

• Provide excellent resistance to bending
• No resistance to rotational or axial loading
• Additional implants are used to provide rotational & axial support for most fractures

Question 11

When should IM pins & multi cerclage wires be used

Answer 11

In spiral or oblique fractures where the length of the fracture line is 2 to 3 times the diaphyseal diameter

Question 12

What is this showing

Answer 12

Question 13

What is critical to avoid interfering w/ the stifle joint

Answer 13

Correct placement of IM pins

Question 14

Why should you just say no to retrograde pinning

Answer 14

Risks damage to intra articular structures in dogs & patellar ligs in cats

Question 15

How do you estimate appropriate pin penetration into a distal bone segment

Answer 15

A 2nd pin equal in length to one in the marrow cavity is used for a point of reference

Question 16

When should pin size be estimated

Answer 16

From pre op radiograph

Question 17

A (smaller/larger) pin may be needed for the curve of the tibia

Answer 17

Smaller

Question 18

How should pins be placed starting @ the proximal tibia

Answer 18

Must be placed in normograde manner & manipulate the hock to ensure the pin doesn’t interfere w/ the joint

Question 19

Describe how to do normograding IM pin

Answer 19

• Insert the pin in the medial aspect of the proximal end of the tibia
• Penetrate the bone midway btw/ the tibial tubercle & medial tibial condyle on the right medial ridge of tibial platea

Question 20

What is this showing

Answer 20

Question 21

What is this showing

Answer 21

Question 22

What is this showing

Answer 22

Question 23

What is this showing

Answer 23

Question 24

What is this showing

Answer 24

Question 25

What is essential w/ tibial fractures

Answer 25

Contouring the plate to match norm configuration of the tibial b/c failure to reproduce can result in valgus or varus angulation of the limb

Question 26

What fractures are these used to stabilize

Answer 26

Transverse or short oblique tibial fractures

Question 27

What fractures are these used to stabilize

Answer 27

Long oblique or reducible comminuted tibial fractures

Question 28

What fractures are these used to stabilize

Answer 28

Nonreducible comminuted tibial fractures

Question 29

What complications can occur w/ tibial & fibular diaphyseal fractures

Answer 29

* Osteomyelitis * Implant migration * Malunion * Delayed union * Nonunion

Question 30

What is a complication that can occur w/ ESF of the tibia

Answer 30

Pin loosening & pin tract drainage

Question 31

What are common errors w/ tibial & fibular diaphyseal fractures

Answer 31

* Poor decision making w/ implant choice * Cats treated w/ rigid ESF may be @ risk for delayed healing or nonunion

Question 32

What is the prognosis of tibial & fibular diaphyseal fractures

Answer 32

Generally good

Question 33

What are the common fractures of the proximal tibial metaphysis & epiphysis

Answer 33

* Usually transverse or short oblique * May be comminuted b/c of severe trauma

Question 34

What do fractures of the distal tibia in mature animals usually involve

Answer 34

Malleoli

Question 35

What is this showing

Answer 35

Question 36

What are these pic showing

Answer 36

Question 37

What is the prognosis of metaphyseal fractures & why

Answer 37

* Heal quickly * Due to large amounts of cancellous bone around the fracture * Trabecular bone heals w/ min formation of callus

Question 38

What are physeal fractures

Answer 38

Through cartilaginous growth plate of proximal or distal tibia or tibial tuberosity in immature animals

Question 39

Cartilaginous physis (stronger/weaker) than surround bone & ligaments

Answer 39

Weaker

Question 40

What salter are proximal tibial physeal fractures usually

Answer 40

Salter I or II

Question 41

What salter are distal tibial physeal fractures usually

Answer 41

Salter I or II

Question 42

Describe radiographs

Answer 42

* Compare to the opp limb (particularly w/ tibial tuberosity avulsions) * Does not provide info about crushing injuries to physis or damage to physeal blood supply * Difficult to give an accurate prognosis for growth w/ these fractures @ time of injury

Question 43

Why are pins placed @ 90 degree angles

Answer 43

To allow for growth

Question 44

What should be used when crossing the physis in animals w/ potential growth

Answer 44

Smooth implants

Question 45

What is this showing

Answer 45

Question 46

Describe fractures through physis of the tibial tuberosity

Answer 46

* Results in proximal displacement of tuberosity * Must be reduced & stabilized to restore quadriceps * Use 2 K wires to stabilize * Use figure 8 ortho wire in large breed dogs

Question 47

What is the prognosis of tibial & fibular physeal fractures

Answer 47

* Excellent * for continued function or growth - depends on amount of damage but prognosis is good * for trauma that crushes the physis it is poor

Question 48

What is seen w/ most trauma induced physeal fractures

Answer 48

They sustain damage to growing cells & have guarded prognosis for growth

Question 49

What is seen w/ premature closure of the proximal or distal tibial physis

Answer 49

* Usually results in short but straight limb * Animal compensates by extending stifle

Question 50

What can occur w/ caudal malalignment of the proximal tibial epiphysis

Answer 50

Increased tibial platea

Question 51

What can occur w/ premature closure of tibial tuberosity physis

Answer 51

* Can alter conformation of the proximal tibia * Results in impaired function & stifle DJD