Long bone fractures/head and neck fractures

Question 1

What is the difference of fracture repair in domestic animals vs. large animals?

Answer 1

Large animals must be ambulatory & fully weight-bearing immediately post-op

Question 2

What are the challenges of fracture fixation in equine?

Answer 2

Large plates make skin closure difficult
Implant failure (excessive movement)
Post-op lameness (contralateral limb laminitis)

Question 3

How many Salter Harris fracture types are there and what are they?

Answer 3

Five

1: through the physis (S-straight)
2: through metaphysis (A-above)
3: through epiphysis (L-Lower)
4: through all (T-through)
5: compression (ER-CRush)

Question 4

What causes the prognosis to decrease when dealing with Salter Harris fractures?

Answer 4

Articular involvement

Question 5

What is a common fracture in young racehorses?

Answer 5

Lateral condylar fractures (vertical fractures of distal cannon bone)

Question 6

Where are the condylar fractures commonly found in thoroughbreds vs. standard bred horses?

Answer 6

TB: Forelimb
SB: equally found on fore/hindlimb

Question 7

What is the typical series of events leading to a condylar fracture?

Answer 7

High compressive load –> sclerosis –> microtrauma –> fracture

Question 8

What type of condylar fractures have the best prognosis?

Answer 8

Non-displaced incomplete fracture

Hx of lameness with acute exacerbation

Question 9

What signs are noticed with acute displaced fractures?

Answer 9

Pain on palpation
Joint effusion
Severe lameness after intense exercise

Question 10

What radiographic view highlights palmar aspect of bone to fully evaluate the joint?

Answer 10

Tangential view

Question 11

What is the sx treatment for a condylar fracture?

Answer 11

Internal fixation with transcortical lag screws

Question 12

How many screws are needed in the internal fixation of a condylar fracture?

Answer 12

2 screws

Question 13

What is the most common long bone fracture in horses?

Answer 13

Cannon bone diaphyseal fractures

Question 14

What is the prognosis dependent upon for cannon bone diaphyseal fractures?

Answer 14

First aid in the field and external coaptation

Question 15

What is the tx for cannon bone diaphyseal fractures?

Answer 15

Double plate fixation

Question 16

What side are the plates placed on for cannon bone fractures?

Answer 16

Tension side, 90 degrees from each other

Question 17

Why are plates offset when treating cannon bone diaphyseal fractures?

Answer 17

To reduce the fulcrum effect

Question 18

What is the maximum amount of compression that is used when using plate holes?

Answer 18

4mm compression

Question 19

What are the four functions of plates and which of these functions is not applied to LA?

Answer 19

1. Compression
2. Neutralization
3. Tension band
4. Buttress- not for LA (not strong enough)

Question 20

What are two advantages of limited contact-dynamic compression plate?

Answer 20

Continuity of bending stiffness

Improved blood supply under plate (can place at 40 degree angle)

Question 21

Which orthopedic plate is specifically made for equine?

Answer 21

Locking compression plate

Question 22

What are ulnar fractures caused by?

Answer 22

Direct trauma

Question 23

What muscle attaches to the olecranon?

Answer 23

Triceps m.

Question 24

What is the characteristic sign of ulnar fractures?

Answer 24

Dropped elbow and carpus in flexion

Question 25

What is disrupted during an ulnar fracture?

Answer 25

Stay apparatus disrupted | Important to splint the carpus in extension before transport so they are weight bearing

Question 26

Where is the splint for transport applied with ulnar fractures?

Answer 26

Palmar splint from fetlock to elbow | **exclusion of the joint above/below rule

Question 27

What do young patients have present that can be confused with an olecranon fracture?

Answer 27

Apophysis

Question 28

What is the tx of choice for ulnar fractures?

Answer 28

Open reduction & Internal fixation using tension band principle

Question 29

Where is the ORIF plate applied in ulnar fractures?

Answer 29

Caudal ulna

Question 30

What is the difference in treatment for patients +/- 250 kg?

Answer 30

> 250 kg: plate required | < 250 kg: tension band wire/cable fixation or hook plates

Question 31

If the horse is not done growing, what should you make sure is not involved in the plate?

Answer 31

Don't involve the radius, can lead to elbow subluxation | *Adult horses you can place distal screws in caudal cortex of radius for more rigid fixation

Question 32

What are the four ddx for ulnar fractures?

Answer 32

Humeral fracture Radial n. paralysis Olecranon fracture Neuro dz (rare)

Question 33

What are femoral physeal fractures caused by?

Answer 33

Dystocia or group housed juvenile cattle mounting each other

Question 34

What is the tx for femoral physeal fractures?

Answer 34

Stall rest & ORIF w/ pins/screws | Foals: dynamic hip screw system

Question 35

What are the tx for tibial fractures in calves vs. foals?

Answer 35

Calves: Thomas Schroeder splint/cast Foal: plate & screw fixation w/ tension band wiring (cancellous screws)

Question 36

How are radial fractures treated?

Answer 36

Double plate fixation

Question 37

What is the minimum amount of pins needed per fragment?

Answer 37

2 pins per fragment | 3-5 in heavier animals

Question 38

When can pins be removed post application?

Answer 38

6-8 weeks then additional stall rest for 2 more weeks

Question 39

What is the difference in type 2 vs. type 3 pin placement?

Answer 39

Type 2: lateral --> medial | Type 3: cranial --> caudal

Question 40

What is bone cement called?

Answer 40

PMMA (plate luting)- creates 100% bone-plate contact increasing strength of repair

Question 41

T/F: You can attempt stall rest for a patient with a femoral fracture

Answer 41

FALSE- this is inappropriate tx for femoral fractures | Leads to severe fragment displacement

Question 42

What is the tx of a femoral fracture for a neonatal calf?

Answer 42

stack pinning & cerclage wire

Question 43

What is the tx of a femoral fracture for young ruminants?

Answer 43

IM pins & cerclage wire w/ active drain | No plates/screws in ruminants <4 mo. because cortical bone is thin/soft

Question 44

What is the tx of a femoral fracture for older/heavier calf?

Answer 44

Stack pinning & type 1 external fixator

Question 45

What is the tx of a femoral fracture for foals?

Answer 45

Double plate application

Question 46

What is the tx of a femoral fracture for adult large animals?

Answer 46

double plate application

Question 47

What type of force do IM pins protect against?

Answer 47

Bending (not axial/compressive) | Slow return to weight bearing

Question 48

T/F: Avulsion fractures of incisors, mandible or premaxilla are common?

Answer 48

TRUE

Question 49

T/F: mandibula region has great vascular supply

Answer 49

TRUE | good functional and cosmetic prognosis

Question 50

T/F: You can remove loose teeth upon discovery of fracture

Answer 50

FALSE-wait for them to declare themselves

Question 51

T/F: No diet modification needed for incisor fractures

Answer 51

TRUE

Question 52

What do you need to watch for when treating a mandibular fracture

Answer 52

Buccal branches of facial n. with maxillary wiring

Question 53

What are the compression surfaces of the mandible?

Answer 53

Ventral/lateral surface

Question 54

What are head/neck fractures caused by?

Answer 54

Trauma

Question 55

What drug should be avoided when a patient has head trauma and increased intracranial pressure?

Answer 55

Ketamine

Question 56

What procedure should be performed if the patient is unable to breathe?

Answer 56

Tracheostomy - Midline of upper 1/3 of neck - Blunt dissection of sternothyrohyoid m. - Remove tracheal ring - Place tube

Question 57

What are problems associated with calvaria fractures?

Answer 57

Subdural hemorrhage and hyphema

Question 58

What is a common head fracture from young horses being halter trained?

Answer 58

Basilar fracture

Question 59

What is a radiographic contrast evaluation of the nasolacrimal duct called?

Answer 59

Dacryocysto-rhinography

Question 60

What catheter is placed in the maxillary sinus if a fracture is present?

Answer 60

Foley catheter (balloon catheter)

Question 61

What type of facial fracture can lead to chemosis?

Answer 61

Zygomatic process fracture

Question 62

Why is sx not commonly required for vertical ramus fractures?

Answer 62

The large masseter m. keeps fragments in place allowing healing

Question 63

What are two causes of neck fractures?

Answer 63

Trauma or electrocution

Question 64

When is static compressive spinal cord lesions clinically relevant?

Answer 64

If both dorsal & ventral contrast columns narrow at the same time

Question 65

What is the tx for static compressive spinal cord lesions?

Answer 65

Dorsal laminectomy or cervical ventral interbody fusion