Fractures

Question 1

What is a dislocation?

Answer 1

Complete joint disruption

Question 2

What is a subluxation?

Answer 2

Partial dislocation

Question 3

How can dislocations be diagnosed?

Answer 3

Clinical exam and radiology

Question 4

Which injuries are associated with dislocations?

Answer 4

• Fractures

- Neurovascular damage

Question 5

What are the long term effects of a dislocation?

Answer 5

• Recurrent instability

- Stiffness

Question 6

Why are open fractures important?

Answer 6

• Higher energy injury
• Increased infection rate
• Soft tissue complications
• Long term morbidity

Question 7

Describe the Gustilo classification of open fractures

Answer 7

• Type 1: wound < 1 cm, clean and simple
• Type 2: wound > 1 cm, moderate tissue damage but simple and adequate skin coverage
• Type 3: extensive soft tissue damage and complex
• 3A: adequate periosteal coverage
• 3B: requires soft tissue covering procedure
• 3C: vascular injury requiring repair

Question 8

How should open fractures be managed?

Answer 8

• Full ATLS assessment and treatment
• Tetanus and antibiotic prophylaxis
• Cefuroxime/ augmentin/ clindamycin - Gent at the time of fixation
• Repeated examination of n/v status
• Wound only handled to remove gross contamination
• Photograph, cover and stabilise limb
• No provisional irrigation/exploration
• Radiographs

Question 9

When is emergency urgent surgery required for an open fracture?

Answer 9

• Polytraumatised patient
• Marine or farmyard environment
• Gross contamination
• Neurovascular compromise
• Compartment syndrome

Question 10

What are the four Cs of surgical debridement and fixation?

Answer 10

• Colour
• Contraction
• Consistency
• Capacity to bleed

Question 11

When should an amputation be considered?

Answer 11

• Insensate limb/foot
• Irretrievable soft tissue or bony tissue
• Other life threatening injuries

Question 12

Describe the features of cortical bone

Answer 12

• Diaphysis
• Resists bending and torsion
• Laid down circumferentially
• Less biologically active

Question 13

Describe the features of cancellous bone

Answer 13

• Metaphysis
• Resists and absorbs - compression
• Site of longitudinal growth
• Very biologically active

Question 14

What is a fracture?

Answer 14

A break in the structural continuity of bone

Question 15

Why can bones fail?

Answer 15

• High energy transfer in normal bones
• Repetitive stress in normal bones
• Low energy transfer in abnormal bones (osteoporosis, metastatic tumour etc.)

Question 16

Describe stage 1 of fracture repair

Answer 16

• Inflammation
• Begins immediately after fracture
• Haematoma and fibrin clot
• Platelets, PMNs, neutrophils, monocytes and macrophages
• By products of cell death - lysosomal enzymes
• Fibroblasts
• Mesenchymal and osteoprogenitor cells
• Angiogenesis

Question 17

How can we affect stage 1 of fracture repair?

Answer 17

• NSAIDs
• Loss of haematoma: open fractures or surgery
• Extensive tissue damage: poor blood supply

Question 18

Describe stage 2 of fracture repair

Answer 18

• Soft callus
• Begins when pain and swelling subside
• Lasts until bony fragments are united by cartilage or fibrous tissue
• Some stability of the fracture
• Angulation can still occur
• Continued increase in vascularity

Question 19

How can we effect stage 2 of fracture repair?

Answer 19

• Replace cartilage

- Bone graft or bone substitutes

Question 20

Which bone graft is the gold standard?

Answer 20

Autogenous cancellous bone graft

Question 21

Describe stage 3 of fracture repair

Answer 21

• Conversion of cartilage to woven bone
• Typical long bone fracture: endochondral and membranous bone formation
• Increasing rigidity and obvious callus

Question 22

Describe stage 4 of fracture repair

Answer 22

• Conversion of woven bone to lamellar bone
• Medullary canal is reconstituted
• Bone responds to loading characteristics Wolff’s law

Question 23

What is delayed union?

Answer 23

-Failure to heal in expected time

Question 24

What are the risk factors for delayed union?

Answer 24

• High energy injury
• Distraction
• Instability
• Infection
• Steroids
• Immune suppressants
• Smoking
• Warfarin
• NSAID
• Ciprofloxacin

Question 25

What is non union and how does it present?

Answer 25

- Failure to heal - Failure of calcification of fibrocartilage - Instability - Abundant callus formation - Pain and tendernes - Persistent fracture line - Sclerosis

Question 26

How can delayed healing be managed?

Answer 26

- Different fixation - Dynamisation - Bone grafting