Lecture Notes on Ankle Fractures

Anatomy of the Ankle

• Bones Involved:
  • Tibia (medial and posterior malleoli)
  • Fibula (lateral malleolus)
  • Talus
• Tibiofibular Syndesmosis:
  • Composed of anterior and posterior inferior tibiofibular ligaments and interosseous membrane.
• Joint Characteristics:
  • Hinge joint allowing plantar and dorsiflexion.
  • Least stable in plantar flexion.
  • Described as a mortise and tenon joint (tibia and fibula form a space for the talus).

Ligament and Stability

• Medial (Deltoid) Ligament:
  • Originates from the medial malleolus, branches into four ligaments.
  • Prevents over eversion.
• Lateral Ligament:
  • Comes from the lateral malleolus, consists of three ligaments.
  • Prevents over inversion.

Types of Ankle Fractures

• Isolated Fractures:
  • Medial/lateral malleolus fractures (70%).
• Bimalleolar Fractures:
  • Fractures of both medial and lateral malleoli (20%).
• Trimalleolar Fractures:
  • Fracture includes the posterior malleolus (less than 10%).
• Syndesmosis Injuries:
  • Occurs in roughly 10% of cases.
• Special Types:
  • Mesonevre Injury: Proximal fibular fracture with syndesmosis and deltoid injury.
  • Pylon Fracture: Fracture of distal tibia including the articular surface.

Classification Systems

• Weber Classification (Lateral malleolus fractures):
  • Type A: Below the syndesmosis.
  • Type B: At the level of syndesmosis.
  • Type C: Proximal to syndesmosis, higher risk of instability.
• Lauge-Hansen Classification:
  • Considers position and force during injury.

Mechanisms and Demographics

• Commonly occurs during ankle inversion, falls, or high energy collisions.
• Most common in males (15-24 years) and females (above 75 years).
• Symptoms:
  • Pain, inability to bear weight, reduced motion range, swelling, bruising, and deformity in displaced fractures.

Diagnostic Approach

• History and Physical Exam
• Imaging:
  • X-rays (Ottawa rules for indication).
  • Typical views: Modified AP View, Lateral View, Weight-bearing/Stress Views.
  • CT for complex fractures, MRI for soft tissue injuries.

Treatment Options

• Conservative Treatment:
  • Stable fractures, non-displaced fractures, or Weber A/B fractures.
• Open Reduction and Internal Fixation (ORIF):
  • Open fractures, unimalliolar fractures with Taylor shift, bimalleolar/trimalleolar fractures, mesonevre/pylon fractures.

Prognosis and Complications

• Recovery: 90% of patients experience little to no ankle pain after one year.
• Complications:
  • Malunion/Non-union, Ankle stiffness, Post-traumatic arthritis.
  • Venous thromboembolism, ulcerations, operative complications (wound healing, infections, nerve injuries).