What are the typical ankle and foot injuries, how are they diagnosed, and what are the recommended treatments?

Ankle and Foot Injury Types, Diagnosis, and Treatment

Common Injury Types

The most common ankle injury is a lateral ankle inversion sprain, accounting for approximately 2 million injuries annually in the United States and representing 20% of all sports injuries. 1

Lateral Ankle Sprains

• Lateral ligament complex injuries are the most frequent, affecting the anterior talofibular ligament (ATFL), calcaneofibular ligament, and posterior talofibular ligament in descending order of frequency 1
• Classified into three grades based on severity 1:
  • Grade I: Mild sprain with minimal ligament damage 1
  • Grade II: Moderate sprain with partial ligament tears (microligament lesions) 1
  • Grade III: Severe sprain with complete ligament rupture 1
• Mechanism: inversion injury occurring in the plantar-flexed position 1

High Ankle (Syndesmotic) Sprains

• Less common but more serious, involving the anterior and posterior tibiofibular ligaments 1
• Mechanism: dorsiflexion and eversion of the ankle with internal rotation of the tibia 1
• These injuries require longer recovery and may need surgical intervention for grade 3 injuries 2

Other Ankle and Foot Injuries

• Medial ankle sprains affecting the deltoid ligament 3
• Achilles and peroneal tendon injuries 4, 3
• Fractures of the malleoli, talus, calcaneus, navicular, base of fifth metatarsal 1, 5
• Osteochondral lesions of the talus 6
• Stress fractures (calcaneus, metatarsals, navicular, anterior tibial cortex) 5

Diagnosis

Initial Clinical Assessment

Obtain history focusing on mechanism of injury, timing, previous ankle sprains, ability to bear weight, and presence of neurovascular symptoms. 1

• Urgent evaluation is required for high pain levels, rapid swelling, coldness/numbness in the foot, inability to bear weight, or complicating conditions like diabetes 1
• Previous ankle sprain is a significant risk factor for recurrent injury 1

Physical Examination

Reexamine the patient 4-5 days after injury when swelling and pain have decreased, as this optimizes diagnostic accuracy with sensitivity of 84% and specificity of 96% for ligament rupture. 1

Key examination findings for severe (Grade III) sprains include 1:

• Swelling and hematoma
• Pain on palpation around the distal fibula
• Positive anterior drawer test (96% of patients with all four findings have lateral ligament rupture) 1

Anterior drawer test: Detects excessive anterior displacement of the talus; if ATFL is torn, the talus subluxates anteriorly compared to the unaffected ankle 1

Crossed-leg test: Apply pressure to the medial knee; pain in the syndesmosis area indicates high ankle sprain 1

Imaging Decision Rules

Use the Ottawa Ankle Rules (OAR) as the primary tool to determine if radiographs are needed, with sensitivity of 86-99% and negative predictive value of 97-99%. 1

Order ankle radiographs if any of the following are present 1:

• Pain in the malleolar zone AND:
  • Bone tenderness at the posterior edge or tip of either malleolus (within 6 cm), OR
  • Inability to bear weight both immediately and when examined (unable to take 4 steps)

Order foot radiographs if 1:

• Pain in the midfoot zone AND:
  • Bone tenderness at the navicular bone, OR
  • Bone tenderness at the base of the fifth metatarsal, OR
  • Inability to bear weight both immediately and when examined

Advanced Imaging

For suspected high-grade ligament injuries, osteochondral defects, syndesmotic injuries, or occult fractures, MRI is the preferred modality with sensitivity of 93-96% and specificity of 100%. 1

• MRI is NOT needed for suspected uncomplicated ATFL rupture, as delayed physical examination (4-5 days) has equivalent diagnostic accuracy 1
• Ultrasonography has sensitivity of 92% but poor specificity (64%) and is operator-dependent 1
• Stress radiographs and arthrography are obsolete and should not be used 1
• MRI is valuable for persistent symptoms to diagnose underlying joint damage 1

Treatment

Acute Phase Management

Implement the PRICE protocol (Protection, Rest, Ice, Compression, Elevation) immediately for all ankle sprains. 1

NSAIDs reduce swelling and pain and may decrease time to return to activities (Level B evidence). 1

• Ice application improves healing and speeds recovery 1
• Control pain and swelling to facilitate early mobilization 1

Functional Support

Use semirigid or lace-up ankle supports rather than elastic bandages for functional treatment (Level B evidence). 1

• Semirigid supports are superior to elastic bandages for treatment 1
• Functional rehabilitation with motion restoration and strengthening exercises is preferred over immobilization 1
• A period of protected weight-bearing with crutches may be necessary for severe injuries to allow proper ligament healing 2

Rehabilitation Protocol

Implement graded exercise regimens with proprioceptive elements such as ankle disk training to reduce risk of recurrent sprains (Level B evidence). 1

Progressive rehabilitation phases 2:

• Acute inflammatory phase: Reduce inflammation, control pain, protect ligament from further injury 2
• Reparative and remodeling phase: Progress rehabilitation to restore mechanical strength and proprioception 2

Prevention of Recurrent Injury

Use semirigid or lace-up ankle supports to decrease risk of recurrent injury, especially in patients with history of recurrent sprains (Level B evidence). 1

• Proprioceptive training programs reduce recurrence risk 1
• Address pain level, workload, and sports participation level early, as these negatively influence recovery 1

Surgical Considerations

Surgery should be considered for grade 3 syndesmotic sprains or ankle sprains recalcitrant to conservative care. 2

• The superiority of surgical repair versus functional rehabilitation for severe lateral ligament rupture remains controversial 1
• Most ankle sprains respond favorably to nonsurgical treatment 2

Common Pitfalls

• Examining too early: Swelling and pain can limit examination accuracy up to 48 hours after injury; wait 4-5 days for optimal assessment 1
• Ordering unnecessary radiographs: Apply OAR strictly to avoid radiation exposure and costs while maintaining 97-99% negative predictive value 1
• Inadequate initial treatment: Leads to chronic problems including decreased range of motion, pain, and joint instability 1
• Missing high ankle sprains: Use crossed-leg test; these require longer recovery and different management 1
• Premature return to activity: Increases risk of chronic ankle instability and recurrent injury 1