Ankle Fractures

Anatomy & Basics - Bones & Bands Bonanza

• Bones: Tibia (medial malleolus, posterior malleolus), Fibula (lateral malleolus), Talus.
• Malleoli: Medial (tibia), Lateral (fibula), Posterior (tibia).
• Syndesmosis (Distal Tibiofibular):
  • Anterior Inferior Tibiofibular Ligament (AITFL)
  • Posterior Inferior Tibiofibular Ligament (PITFL)
  • Interosseous Ligament (IOL)
  • Transverse Ligament
• Major Ligaments:
  • Medial: Deltoid complex (superficial & deep)
  • Lateral: Anterior Talofibular (ATFL), Calcaneofibular (CFL), Posterior Talofibular (PTFL).

⭐ The posterior malleolus is an extension of the posterior tibial plafond and its fracture often indicates significant injury and potential instability requiring fixation if >25% of articular surface or >2 mm displacement is involved.

📌 Mnemonic (Lateral Ligaments): Always Take Five Lads; Can Feel Love; Please Take Five Lasses (ATFL, CFL, PTFL from anterior to posterior).

Classification Systems - Cracking the Codes

Predict stability & guide treatment:

• Lauge-Hansen Classification: Mechanism-based. 📌 SAD, SER, PAB, PER.

  Type	Fibula Fracture	Medial Injury	Other Key Injuries
  SAD	Transverse, below syndesmosis	Vertical Med. Mall.
  SER	Spiral, at syndesmosis	Med. Mall. / Deltoid	Post. Mall. # / PITFL tear
  PAB	Trans/Obl, above syndesmosis	Med. Mall. / Deltoid	Syndesmotic injury
  PER	High Spiral, above syndesmosis	Med. Mall. / Deltoid	Ant/Post Syndesmotic, Interosseous memb.

• Danis-Weber Classification: Fibular # level to syndesmosis.

  • Type A: Fibula # below syndesmosis. Intact. Stable.
  • Type B: Fibula # at syndesmosis. Injury variable.
  • Type C: Fibula # above syndesmosis. Disrupted. Unstable.

  ⭐ Weber C fractures, with fibular fracture proximal to the syndesmosis, are considered unstable and often require syndesmotic screw fixation.

Clinical Features & Diagnosis - Spotting the Snaps

• Presentation: Acute pain, swelling, deformity, ecchymosis, can't bear weight.
• Examination: Palpate: tenderness, crepitus. Stability: Squeeze, external rotation, Cotton tests.
• 📌 Ottawa Ankle Rules: Guides X-ray. Malleolar/midfoot pain + bone tenderness (post. malleoli, navicular, 5th MT base) OR no weight bearing (4 steps).
• Imaging:
  • X-rays: AP, Lateral, Mortise (for syndesmosis; medial clear space, tibiofibular overlap).
  • CT: Complex fractures, pre-op planning.
  • MRI: Ligamentous/soft tissue injuries.

⭐ The mortise view X-ray is crucial for assessing ankle joint congruity; a medial clear space >4mm suggests deltoid ligament injury and instability.

Management Principles - Mending Methods

Principles: Anatomical reduction, stable internal fixation, early mobilization.

• Non-Operative Treatment:
  • Indications: Stable, undisplaced fractures (e.g., isolated Weber A).
  • Methods: Below-knee cast, walking boot.
• Operative Treatment (ORIF):
  • Indications: Unstable fractures, displaced fractures >2mm, open fractures, syndesmotic disruption, bimalleolar/trimalleolar fractures.
  • Techniques:
    • Lateral Malleolus: Anatomical plate & screws (lag screw if possible).
    • Medial Malleolus: Cannulated screws, anti-glide plate, tension band wiring.
    • Posterior Malleolus: Screws (direct posterior/posterolateral approach), buttress plate.
    • Syndesmosis: Screws (e.g., 1-2 trans-syndesmotic screws, 3 or 4 cortices), suture button devices.

⭐ Anatomical reduction of the ankle mortise is paramount; even 1mm of lateral talar shift can reduce the tibiotalar contact area by approximately 42%, leading to early arthritis.

Complications - Pitfalls & Problems

• Early:
  • Wound infection, skin necrosis
  • Neurovascular injury (nerve/vessel)
  • Compartment syndrome (↑ pressure)
  • DVT/PE
• Late:
  • Malunion (deformity), nonunion (no union)
  • Stiffness, ↓ range of motion
  • Post-traumatic osteoarthritis (PTOA)
  • Implant issues (pain, loosening)
  • Chronic pain, CRPS

⭐ Post-traumatic osteoarthritis is the most common long-term complication following an ankle fracture, particularly if anatomical reduction is not achieved.

High‑Yield Points - ⚡ Biggest Takeaways

• Lauge-Hansen classification: mechanism-based (foot position, deforming force).
• Weber classification: fibular fracture level relative to syndesmosis (A: infra-, B: trans-, C: supra-).
• Maisonneuve fracture: proximal fibula fracture + syndesmotic injury ± medial injury.
• Tillaux fracture: Salter-Harris III of anterolateral distal tibial epiphysis.
• Bosworth fracture-dislocation: rare, irreducible posterior fibular dislocation.
• Unstable syndesmotic injuries often require surgical fixation.
• Trimalleolar fracture involves medial, lateral, and posterior malleoli.