Ankle Sprains and Instability

Ankle Blueprint - Ligaments & Movers

• Bony Core: Ankle mortise (Tibia, Fibula, Talus) forms talocrural joint.
• Lateral Ligaments (LCL):
  • ATFL (Anterior Talofibular): Resists inversion in plantarflexion. 📌 Always Tears First Ligament.
  • CFL (Calcaneofibular): Resists inversion in neutral/dorsiflexion.
  • PTFL (Posterior Talofibular): Strongest lateral; resists posterior talar shift.
• Medial Ligament: Deltoid Ligament (strong multi-component structure; resists eversion).
• Syndesmosis (High Ankle): AITFL, PITFL, IOL (Interosseous Ligament), Transverse Ligament; crucial for mortise stability.
• Prime Movers & Actions:
  • Dorsiflexion: Tibialis Anterior.
  • Plantarflexion: Gastrocnemius, Soleus (Achilles tendon).
  • Inversion: Tibialis Posterior.
  • Eversion: Peroneus Longus & Brevis.

⭐ The ATFL is the most frequently injured ligament in the ankle, typically during an inversion injury with the foot in plantarflexion.

Sprain Central - Types, Grades, & Tests

• Types of Sprains:

  • Lateral (Inversion, ~85%): ATFL (most common), CFL, PTFL.
  • Medial (Eversion): Deltoid ligament. Less common, more severe.
  • Syndesmotic (High Ankle): AITFL, PITFL. External rotation/dorsiflexion. Prolonged recovery.

• Grades of Ligament Injury:

  • Grade I: Micro-tears (stretch). Minimal pain, no instability.
  • Grade II: Partial tear. Moderate pain/swelling, mild instability. Weight-bearing painful.
  • Grade III: Complete tear. Severe pain/swelling, significant instability. Unable to bear weight.

• Key Special Tests:

  • Anterior Drawer: ATFL. +ve: >5mm anterior translation.

  • Talar Tilt: CFL (inversion), Deltoid (eversion). +ve: >10-15° tilt vs contralateral.

  • Squeeze Test / External Rotation (Kleiger's): For syndesmotic injury.

• 📌 Ottawa Ankle Rules (Exclude Fracture): X-ray if pain in malleolar zone + tenderness post. lat/med malleolus OR inability to bear weight (4 steps); OR pain in midfoot zone + tenderness navicular/base 5th MT OR inability to bear weight (4 steps).

⭐ ATFL is the most injured ankle ligament. High ankle sprains (syndesmotic) require significantly longer recovery, often double that of lateral sprains.

Road to Recovery - Acute Care & Rehab

• Acute Management:

  • 📌 POLICE: Protection, Optimal Loading, Ice (15-20 min), Compression, Elevation.
  • Analgesia: NSAIDs.
  • Immobilization: Functional brace/taping (Grade I/II). Short-term cast/boot for severe (Grade III) (~1-3 wks).
  • Weight-bearing: As tolerated (WBAT), progressive.

• Rehabilitation (Phased Approach):

  • Phase 1 (Acute, ~1 wk): ↓ pain/swelling, protected ROM (ankle pumps).
  • Phase 2 (Subacute, ~2-4 wks): Restore ROM, ↑ strength (therabands), flexibility.
  • Phase 3 (Intermediate, ~4-8 wks): Proprioception (balance board), neuromuscular control, functional exercises.
  • Phase 4 (Advanced, >8 wks): Sport-specific drills, agility, plyometrics. Gradual return to play.

• Adjuncts:

  • Taping/bracing for support during activity & secondary prevention.

⭐ Early functional rehabilitation (EFR) with protected weight-bearing is superior to prolonged immobilization for most Grade I/II ankle sprains, promoting faster recovery.

Management Algorithm:

Chronic Wobbles - Instability & Issues

• Chronic Ankle Instability (CAI): Recurrent "giving way" >12 months post-sprain.
• Types:
  • Mechanical: Ligament laxity (e.g., ATFL, CFL). Positive stress tests (anterior drawer, talar tilt).
  • Functional: Subjective instability; proprioceptive/neuromuscular deficits.
• Associated: Osteochondral Lesions of Talus (OLT), peroneal tendinopathy/subluxation, anterolateral impingement, sinus tarsi syndrome.
• Dx: History, clinical exam, stress X-rays, MRI (for OLT, tendons).
• Rx:
  • Conservative: Physiotherapy (proprioception, peroneal strengthening), bracing/taping.
  • Surgical (if conservative fails):
    • Anatomic repair: Brostrom-Gould (ATFL ± CFL repair, often with retinacular augmentation).
    • Arthroscopy: Address associated intra-articular lesions (OLT, impingement).

⭐ Osteochondral lesions of the talus (OLT) are frequently found in up to 70% of patients with chronic ankle instability undergoing surgery.

High‑Yield Points - ⚡ Biggest Takeaways

• ATFL is the most common ligament injured, usually by inversion and plantarflexion.
• Ottawa Ankle Rules determine need for X-ray to rule out malleolar or midfoot fractures.
• Key tests: Anterior Drawer for ATFL, Talar Tilt for CFL.
• Grade III sprains mean complete tear and gross instability.
• Chronic instability often needs surgical intervention (e.g., Broström-Gould).
• High ankle sprains (syndesmotic) have prolonged recovery; test with Squeeze test.