Ankle Instability

Definition:
Ankle instability is a condition where the ankle repeatedly "gives way," particularly during walking or physical activity. It often follows recurrent ankle sprains and results from weakened or torn ligaments, poor neuromuscular control, or mechanical laxity.

1. Functional Instability:
   
   • Normal ligament anatomy, but impaired proprioception, neuromuscular control, or strength.
   • Often described as a sensation of the ankle "giving out."

1. Mechanical Instability:
   
   • True ligament laxity due to incomplete healing or repeated ligamentous injury.
   • Objectively measurable looseness on physical exam or imaging.

• Inadequately treated or repeated ankle sprains
• Ligament laxity (most commonly affecting the anterior talofibular and calcaneofibular ligaments)
• Weak peroneal muscles
• Poor proprioception and balance
• Flatfoot or cavus deformity contributing to altered biomechanics

• Recurrent episodes of the ankle turning or rolling
• Chronic pain or tenderness over the lateral ankle
• Swelling and stiffness
• Feeling of instability or weakness, especially on uneven surfaces or during athletic activity

• History: Repeated sprains or sensations of ankle giving way
• Physical Exam: Anterior drawer and talar tilt tests
• Imaging:
  
  • X-rays: Rule out fractures or bony alignment issues
  • Stress X-rays: Assess mechanical instability
  • MRI: Evaluate ligament damage and soft tissue involvement

• Physical Therapy:
  
  • Proprioception/balance training
  • Strengthening peroneal and intrinsic foot muscles
  • Neuromuscular re-education
• Bracing or Taping: Support during activity
• Orthotics: Address underlying biomechanical contributors

• Broström Procedure: Direct repair of lateral ankle ligaments (most common)
• Anatomic Ligament Reconstruction: Use of tendon graft for more extensive injury
• Adjunctive Procedures: Address cavus foot, peroneal tendon pathology, or osteochondral lesions if present

• Conservative care is effective in many cases, especially for functional instability.
• Surgical outcomes are generally excellent for patients with mechanical instability who fail non-operative management.
• Delayed treatment may lead to chronic pain, peroneal tendon injury, or early ankle arthritis.