Ankle fracture

Ankle fractures are the most common fractures of the lower extremity. They are most often caused by twisting the ankle, the circumstances of which the patient will typically recall. The major symptoms are pain in the affected area and decreased range of motion. If physical examination and the patient history suggest a fracture (e.g., patient is unable to bear weight on the affected leg), an x-ray is performed. The most important diagnostic consideration is whether the fracture is stable (as is the case in isolated malleolar fractures) or unstable (e.g., bimalleolar fracture). Unstable fractures require surgery, whereas stable fractures can be treated conservatively with a short leg cast.

• Supination or pronation trauma (“twisted ankle”)

References:^[1]

Weber classification of ankle fractures

The Weber classification categorizes ankle fractures according to the level of the fibular fracture in relation to the ankle syndesmosis (tibiofibular syndesmosis).^[2]

• Weber A: lateral malleolar fracture below the syndesmosis
  • Intact syndesmosis and deltoid ligament
  • Possible medial malleolar fracture
  • Usually stable
• Weber B: fibular fracture at the level of the syndesmosis
  • Possible syndesmotic injury and/or deltoid ligament injury
  • Variable stability
• Weber C: fibular fracture above the syndesmosis
  • Ruptured syndesmosis, torn interosseous membrane
  • Medial malleolus fracture and/or deltoid ligament tear
  • Unstable
• Maisonneuve fracture: proximal subcapital Weber C fracture (or avulsion fracture of the lateral collateral ligament) ^[3]
  • Ruptured syndesmosis
  • Medial malleolus fracture and/or deltoid ligament tear
  • Unstable
  • Simultaneous interosseous membrane tears ^[1]

Special forms

• Avulsion of a bony fragment from the posterior tibial margin (Volkmann triangle) ^[4]
• Pilon fracture: fracture of the distal tibia that involves the tibial part of the talocrural joint and is frequently associated with fibular fractures

• Local pain, swelling and hematoma
• Tenderness, especially in the area of the malleoli, the syndesmosis, and the posterior aspect of the ankle joint
• Restricted range of movement
• Skin abnormalities (lacerations, discolorations, tenting, or blistering)
• If separation of the ankle mortise elements occurs: lateral displacement of the foot
• In some cases, accompanying injury (e.g., fracture of the proximal fibula, knee, or foot)

• Physical examination
  • Check for neurovascular deficits
  • See “Ottawa ankle rules.”
• 3-view plain x-ray: anteroposterior (AP); , lateral and oblique view
  • Evaluate articular surfaces
  • Compare joint spaces between talus and medial malleolus, talus and lateral malleolus, and talus and tibial plafond
  • Check for breaks in the ring of the ankle joint and for bony fractures

• Initial management: rest, ice, compression, and elevation
• Conservative treatment
  • Indications: stable fractures (isolated/nondisplaced malleolar fractures)
  • Short leg cast for 4–6 weeks
• Surgical treatment: to ensure normal alignment of bone and cartilage to prevent ankle arthritis and to regain functionality
  • Indications: unstable/displaced fractures, open ankle fractures, and cases of neurovascular damage
  • Technique: reposition and internal or external fixation with metal plates and/or screws

• General complications of fractures
• Damage to the peroneal nerve or saphenous nerve
• Post-traumatic osteoarthritis

We list the most important complications. The selection is not exhaustive.

1. Dähnert W. Radiology Review Manual. Lippincott Williams & Wilkins ; 2011
2. Weber classification of ankle fractures. https://radiopaedia.org/articles/weber-classification-of-ankle-fractures. Updated: January 1, 2016. Accessed: December 8, 2016.
3. Maisonneuve fracture. https://radiopaedia.org/articles/maisonneuve-fracture. Updated: January 1, 2016. Accessed: December 8, 2016.
4. Neumaier Probst E, Maas R, Meenen NM. Isolated Fracture of the posterolateral tibial lip (Volkmanns's triangle). Acta Radiologica. 1997; 38 (3): p.359-362. doi: 10.1080/02841859709172083 . | Open in Read by QxMD
5. Ankle radiograph (an approach). https://radiopaedia.org/articles/ankle-radiograph-an-approach. Updated: January 1, 2016. Accessed: December 8, 2016.