Antebrachium

Question 1

What are monteggia fractures?

Answer 1

Fracture of the proximal ulna with concurrent luxation of the radial head

Question 2

How are Monteggia fractures classified?

Answer 2

According to the direction of luxation of the radial head

Question 3

What are the classification of Monteggia fractures?

Answer 3

Type I: Cranial dislocation
Type II: Caudal dislocation
Type III: Lateral/Craniolateral dislocation
Type IV: Cranial dislocation with concurrent radial fracture

Question 4

Why do we NOT IM pin the radius?

Answer 4

80% complication rate!
- distrupts radial blood supply
- damages antebrachial joint
- poor rotational stability
- malalignement

Question 5

Properties of diaphyseal fractures of the Ulna?

Answer 5

• usually occur with radial fractures
• repair of radius only is sufficient
• if radial fracture comminuted or large patient then internal fixation of ulnar concurrently advised - plate or IM pin

Question 6

What is the most common radial diaphyseal fracture?

Answer 6

Distal 1/3 morst common

tx by plate or ESF

Question 7

What is the complication rate of diaphyseal/metaphyseal fractures?

Answer 7

54%

Question 8

Minimising complications in small breed radius and ulna fracture repair?

Answer 8

• consider internal fixation as a first line approach
• titanium implants - less stress protection
• locking plate and screws, screw less likely to strip/loosen
• choose a plate that spans the entire length of the bone
• consider bonegrafting

Question 9

Why is stabilisation of the ulna recommended in cats suffering radius/ulna diaphyseal/metaphyseal fractures?

Answer 9

Increased supination/pronation compared to dogs!
Studies documents an increased rate of complications in cats suffering radius and ulnar fracture where only the radius is stabilized

Recommended to stabilise the ulna as well in all cases (e.g. IM pin ulna + plate radius)