Fractures: Ankle and Foot

Question 1

What are the Ottawa ankle rules used for?

Answer 1

Determine if x-rays are necessary for ankle fracture Ix

Question 2

What do the Ottawa ankle rules state?

Answer 2

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

1. Inability to weight bear for 4 steps
2 and 3. Bone tenderness over posterior edge or tip of lat/med malleolus

Question 3

Describe the Weber classification of ankle fractures?

Answer 3

A: below the syndesmosis
B: start at the level of the tibial plafond and may extend proximally to involve the syndesmosis
C: above the syndesmosis (which may itself be damaged)

Question 4

What is a Maisonneuve fracture?

Answer 4

Spiral fibular fracture that disrupts the syndesmosis + widens the ankle joint

REQUIRES SURGERY

Question 5

Mx of ankle joint fracture?

Answer 5

All: prompt reduction (remove pressure -> necrosis)

Young + unstable high velocity OR proximal: surgical repair (usually compression plate)

Elderly OR young stable: conservative (thin bone doesn’t hold metalwork well)

Question 6

Mx of young pt with Weber A/C ankle fracture?

Answer 6

A (stable): WB as tolerated in CAM boot for 6 weeks
C (unstable): OREF

Question 7

What does CAM in “CAM boot” stand for?

Answer 7

Controlled ankle motion

Question 8

MT most commonly affected by stress fracture?

Answer 8

Second (as it’s the longest)

Question 9

What is a stress fracture?

Answer 9

Fracture due to repeated mechanical stress

Question 10

What is the most and least commonly fractured metatarsal?

Answer 10

Most - fifth
Least - first

Question 11

What is the most common site of midfoot fractures?

Answer 11

Fifth metatarsal

Question 12

Jones vs. Pseudo-jones MT fractures?

Answer 12

Pseudo-jones: most common, proximal avulsion fracture, occurs at proximal tuberosity, usually a/w lat ankle sprain + inversion ankle injury

Jones: less common, transverse fracture at metaphyseal-diaphyseal junction

Question 13

What are features of a MT fracture?

Answer 13

Pain and bony tenderness
Swelling
Antalgic gait

Question 14

In whom do 5th MT # occur?

Answer 14

Athletes
But can happen after simple accidents

Question 15

In whom do 2nd MT # occur?

Answer 15

Healthy athletes, e.g. runners

Question 16

When do avulsion 5th MT # occur?

Answer 16

When peroneus brevis pulls on proximal part of 5th MT during foot inversion

Question 17

Ix for MT #?

Answer 17

X-ray (displaced or non-displaced)
Isotope scan or MRI if ?stress fracture (as x-ray often normal)

Question 18

How may x-rays appear in stress fractures?

Answer 18

Normal in 50%
But sometimes there’s periosteal reaction seen 2-3wks later

Question 19

how can MT5 fractures be divided?

Answer 19

3 zones - depends on MOI and affected part

zone 1 - inversion injury, base of 5MT where peroneus brevis inserts
zone 2 - forefoot adduction, affects metaphyseal-diaphyseal junction (Jones fracture)
zone 3 - repetitive microtrauma causes stress fracture affecting diaphysis

Question 20

what is the most common type of MT5 fracture?

Answer 20

zone 1 - 70%
zone 2 - 20%

Question 21

stress fractures of MT5 affect?

Answer 21

the diaphysis
can be due to rotational injury causing spiral fracture or repetitive trauma

Question 22

requirement for x-ray if there is midfoot pain?

Answer 22

foot x-ray is only required if there is midfoot zone pain and any of the below:

Bone tenderness at base of the fifth metatarsal.
Bone tenderness at navicular bone.
Inability to bear weight both immediately and in emergency department for four steps.

Question 23

why might ottawa ankle rules not be accurate?

Answer 23

pt is intoxicated or has reduced consciousness
pt has other distracting painful injuries
pt has evidence of reduced sensation in lower limb