Fractures: Ankle and Foot Flashcards
What are the Ottawa ankle rules used for?
Determine if x-rays are necessary for ankle fracture Ix
What do the Ottawa ankle rules state?
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
Describe the Weber classification of ankle fractures?
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)
What is a Maisonneuve fracture?
Spiral fibular fracture that disrupts the syndesmosis + widens the ankle joint
REQUIRES SURGERY
Mx of ankle joint fracture?
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)
Mx of young pt with Weber A/C ankle fracture?
A (stable): WB as tolerated in CAM boot for 6 weeks
C (unstable): OREF
What does CAM in “CAM boot” stand for?
Controlled ankle motion
MT most commonly affected by stress fracture?
Second (as it’s the longest)
What is a stress fracture?
Fracture due to repeated mechanical stress
What is the most and least commonly fractured metatarsal?
Most - fifth
Least - first
What is the most common site of midfoot fractures?
Fifth metatarsal
Jones vs. Pseudo-jones MT fractures?
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
What are features of a MT fracture?
Pain and bony tenderness
Swelling
Antalgic gait
In whom do 5th MT # occur?
Athletes
But can happen after simple accidents
In whom do 2nd MT # occur?
Healthy athletes, e.g. runners
When do avulsion 5th MT # occur?
When peroneus brevis pulls on proximal part of 5th MT during foot inversion
Ix for MT #?
X-ray (displaced or non-displaced)
Isotope scan or MRI if ?stress fracture (as x-ray often normal)
How may x-rays appear in stress fractures?
Normal in 50%
But sometimes there’s periosteal reaction seen 2-3wks later
how can MT5 fractures be divided?
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
what is the most common type of MT5 fracture?
zone 1 - 70%
zone 2 - 20%
stress fractures of MT5 affect?
the diaphysis
can be due to rotational injury causing spiral fracture or repetitive trauma
requirement for x-ray if there is midfoot pain?
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.
why might ottawa ankle rules not be accurate?
pt is intoxicated or has reduced consciousness
pt has other distracting painful injuries
pt has evidence of reduced sensation in lower limb
