What is the initial approach to managing a patient with weakness on dorsiflexion of the ankle?

Management of Ankle Dorsiflexion Weakness

For patients presenting with ankle dorsiflexion weakness, functional rehabilitation with motion restoration and strengthening exercises is the recommended initial approach to management, as this improves outcomes related to mobility, stability, and prevention of recurrent injury. 1

Initial Assessment

When evaluating ankle dorsiflexion weakness, perform:

1. Detailed history:

   • Mechanism of injury (if applicable)
   • Timing of symptom onset
   • History of previous ankle injuries (significant risk factor)
   • Functional limitations (walking difficulties, instability)

2. Physical examination:

   • Strength testing: Compare bilateral ankle dorsiflexion strength
   • Range of motion assessment: Normal ankle dorsiflexion is approximately 22-23° non-weight bearing and 33-34° weight bearing 2
   • Neurovascular assessment: Check pedal pulses and sensation
   • Special tests:
     • Thompson test (for Achilles tendon integrity)
     • Anterior drawer test (for ligamentous stability)
     • Crossed-leg test (for high ankle sprain)

Diagnostic Considerations

Ankle dorsiflexion weakness may result from:

• Lateral ankle sprain: Most common acute injury, typically from inversion mechanism 1
• Peroneal nerve injury: Causes isolated dorsiflexion weakness
• Functional neurological disorder: May present with variable weakness patterns 1
• Achilles tendon pathology: Can affect ankle mechanics and dorsiflexion 1
• Peripheral arterial disease: May present with claudication and weakness 1

Treatment Algorithm

Step 1: Acute Phase (0-72 hours post-injury)

• PRICE protocol: Protection, Rest, Ice, Compression, and Elevation 1
• NSAIDs: Help reduce swelling and pain, speed recovery 1
• Avoid immobilization: Early functional rehabilitation is preferred over immobilization 1

Step 2: Rehabilitation Phase

• Motion restoration exercises:

  • Active and passive ankle dorsiflexion exercises
  • Gentle stretching of plantar flexors (gastrocnemius and soleus)
  • Joint mobilization techniques

• Strengthening exercises:

  • Progressive resistance exercises for tibialis anterior
  • Eccentric strengthening of antagonist muscles
  • Bilateral exercises to promote symmetrical strength

• Proprioceptive training:

  • Ankle disk training
  • Balance exercises
  • Weight-bearing exercises with proper alignment

Step 3: Functional Phase

• Task-specific training:

  • Gait training with focus on proper heel strike and push-off
  • Activities that promote normal movement patterns and even weight-bearing 1
  • Gradual return to sport-specific movements

• Support devices:

  • Semirigid or lace-up ankle supports are superior to elastic bandages 1
  • Particularly beneficial for patients with history of recurrent sprains 1

Evidence-Based Considerations

1. Functional rehabilitation is superior: Research shows that functional rehabilitation with motion restoration and strengthening exercises is preferred over immobilization for most ankle injuries 1.

2. Proprioceptive training is beneficial: Ankle disk or proprioceptive neuromuscular facilitation exercise regimens help reduce the risk of ankle sprain recurrence 1, 3.

3. Support devices prevent recurrence: Semirigid or lace-up ankle supports provide protection against future ankle sprains, especially in those with history of recurrent sprains 1.

4. Avoid prolonged splinting: Splinting may prevent restoration of normal movement and function, potentially leading to muscle deconditioning, learnt non-use, and increased pain 1.

Common Pitfalls to Avoid

1. Overlooking neurological causes: Dorsiflexion weakness may indicate peroneal nerve injury or other neurological conditions, not just musculoskeletal injury.

2. Premature return to activity: Inadequate rehabilitation can lead to chronic problems including decreased range of motion, pain, and joint instability 1.

3. Neglecting proprioception: Focusing only on strength without addressing proprioceptive deficits increases risk of recurrent injury 1, 4.

4. Over-reliance on passive modalities: Active rehabilitation strategies produce better long-term outcomes than passive treatments alone.

5. Ignoring biomechanical factors: Limited dorsiflexion ROM is associated with altered landing biomechanics and increased injury risk 4, requiring comprehensive correction 3.

By following this structured approach to management, patients with ankle dorsiflexion weakness can achieve improved function, reduced pain, and decreased risk of recurrent injury.