Tibia/Fibula/Ankle Fractures

Question 1

Why are open fractures more common in the lower leg

Answer 1

Superficial position of the tibia

Question 2

What are the mechanisms of injury to the tibia/fibula

Answer 2

Low energy fractures - invariable twisting, inversion or eversion injuries, and often occur following a fall from standing height.

High-energy fractures are caused typically by a direct blow to the tibia and fibula resulting in fracture comminution and soiling of the wound.

Question 3

What should you assess a patient with ankle fracture for?

Answer 3

Swelling, bruising, deformity, skin piercing
Neurovascular status of limb
Compartment syndrome

Question 4

What would you order for a lower leg fracture?

Answer 4

Plain radiograph

CT for tibial plateau and Pilon fractures

Question 5

What are Pilon/Plafond fractures?

Answer 5

Intra-articular fractures of the ankle joint

Only extra-articular fractures of the ankle are ankle fractures

Question 6

How are ankle fractures classified?

Answer 6

Weber classification
Type A - fibular fracture below the syndesmosis
Type B - fibula fracture start at the level of the tibial plafond (end of the tibia) and extend to the level of the syndesmosis
Type C - fibula fracture above the level of the syndesmosis

Syndesmosis is the fibrous joint between the tibia and fibula at the ankle

Question 7

How are lower leg fractures managed?

Answer 7

Fracture reduction - typically under sedation
Limb should be placed in a back-slab
- above knee for tibial plateau and diaphysial fractures and below knee for Pilon and ankle fractures
before repeating NV exam and obtaining repeat plain film radiograph.
Repeat reduction until successful

Manage any signs of compartment syndrome

Question 8

What is definitive management for lower leg fractures?

Answer 8

Tibial plateau - require surgical fixation
Tibial diaphysis and Pilon fractures (unless undisplayed) require surgical fixation
Ankle fractures require surgical fixation

Question 9

How should na open fracture be managed?

Answer 9

Wound cleaned and gross contamination removed
Photograph the wound
Cover with saline soaked gauze
IV abs
Debridement and fixation + plastic involvement

Question 10

What are complications of tibia/fibular fractures?

Answer 10

Immediate:
Compartment syndrome
NV compromise

Delayed:
Infection
Malunion - the degree of angulation is important as it can lead to early onset OA
Non-union - high energy fractures with bone loss may need bone grafting
Joint stiffness

Question 11

What are the Ottawa ankle rules?

Answer 11

X-rays are only necessary if there is pain in the malleolar zone and:

1. Inability to weight bear for 4 steps
2. Tenderness over the distal tibia, medial malleolar zone
3. Bone tenderness over the distal fibula, lateral malleolar zone

Question 12

What is a Pott’s fracture?

Answer 12

A bimalleolar (medial and lateral) or trimalleolar (medial, lateral and posterior) fracture.
Produced by forced eversion of the foot:
Forced eversion pulls on the medial ligaments producing an avulsion fracture of the medial malleolus
Talus moves laterally, breaking off the lateral malleolus
TIbia is forced anteriorly, shearing off the distal and posterior part against the talus

Question 13

What might a fibular neck fracture cause?

Answer 13

Damage to the common fibular nerve which wraps around it
Loss of ability to dorsiflex foot - foot drop
Weakness of foot eversion
Weakness of extensor hallows longus
Loss of sensation over dorsal and lateral side of the leg - innervation is preserved on medial side (saphenous nerve from femoral) and heel and sole (tibial nerve from sciatic)
Wasting of anterior tibial and peroneal (fibular) muscles