What is the diagnosis and treatment plan for a patient with a history of twisting their left ankle, unable to weightbear, with medial tenderness, moderate ankle joint effusion, ruptured Anterior Talofibular Ligament (ATFL), and moderate sprain of the Calcaneofibular Ligament (CFL)?

Diagnosis and Treatment of Severe Lateral Ankle Sprain with ATFL Rupture

This patient has a severe grade III lateral ankle sprain with complete ATFL rupture and moderate CFL sprain that should be managed with immediate functional treatment including RICE protocol, short-term immobilization with a removable boot, and early progressive weight-bearing as tolerated, followed by structured physical therapy with proprioceptive training to prevent chronic ankle instability. 1, 2

Diagnostic Confirmation

The ultrasound findings confirm a severe lateral ankle injury with:

• Complete ATFL rupture (most commonly injured lateral ligament) 2, 3
• Moderate CFL sprain at the fibular attachment (critical for talar tilt stability) 4
• Deep deltoid ligament injury (moderate sprain or contusion) 3
• Moderate ankle joint effusion 3

Fracture exclusion is essential: Given the inability to weight-bear and medial tenderness, Ottawa Ankle Rules should guide radiographic imaging to rule out fractures of the malleoli, base of fifth metatarsal, or navicular bone before proceeding with treatment. 1, 2

Treatment Algorithm

Phase 1: Immediate Management (Days 0-5)

RICE protocol with protected weight-bearing:

• Rest, ice, compression, and elevation immediately 1
• Removable boot or ankle brace for protection while allowing weight-bearing as tolerated 5
• Assistive devices (crutches) for comfort initially but not mandatory if patient can tolerate full weight-bearing 5
• Early weight-bearing prevents muscle atrophy and joint stiffness 5

Critical pitfall to avoid: Do not rely on immediate physical examination to assess ligament rupture severity due to excessive swelling and pain in the first 48 hours. 2

Phase 2: Early Functional Treatment (Days 5-14)

Progressive mobilization and strengthening:

• Begin range of motion exercises early 1, 6
• Gradual increase in weight-bearing as pain allows 5
• Early functional treatment provides fastest recovery of ankle mobility and earliest return to activity without affecting late mechanical stability 6

Phase 3: Neuromuscular Rehabilitation (Weeks 3-8)

Proprioceptive training is essential:

• Tilt board exercises after 3-4 weeks improve balance and neuromuscular control 1
• Address dynamic postural control deficiencies to prevent chronic ankle instability (CAI) 1
• Up to 40% of patients develop CAI despite initial treatment, making structured physical therapy critical 1

Conservative vs. Surgical Management

Conservative functional treatment is strongly recommended over surgery for this acute injury:

• Meta-analysis shows functional treatment provides fastest recovery without affecting late mechanical stability 6
• Functional treatment is complication-free, whereas surgery has serious though infrequent complications 6
• Secondary surgical repair years after injury has results comparable to primary repair, so even competitive athletes can receive initial conservative treatment 6
• Surgery should be reserved for chronic instability refractory to 6+ months of conservative treatment 6

Biomechanical considerations: The CFL is a primary stabilizer for talar tilt, and its moderate sprain in this case contributes significantly to instability. 7, 4 However, this does not change the initial conservative approach, as functional treatment addresses both ATFL and CFL injuries effectively. 6

Prognostic Factors and Monitoring

Risk factors for developing chronic ankle instability in this patient:

• Inability to weight-bear (present in this case) 1
• Moderate to severe ligament injury 1
• Inability to complete jumping and landing within 2 weeks predicts CAI development 1
• Lack of mechanical stability or increased ligament laxity at 8 weeks post-injury 1

Follow-up protocol:

• Monitor for displacement or instability on follow-up imaging 5
• Reassess if pain worsens or fails to improve 5
• If symptoms persist beyond 3-6 months with functional instability despite rehabilitation, consider MRI to evaluate for underlying joint damage 2

Special Considerations

The deep deltoid ligament injury requires attention:

• This medial-sided injury is less common but documented in comprehensive ultrasound evaluations 3
• Does not change the functional treatment approach but may prolong recovery 3

Prevention of recurrence:

• Previous ankle sprain is the most significant risk factor for re-injury 2
• Long-term ankle bracing or taping during sports may be beneficial 1
• Continued proprioceptive exercises beyond initial healing 1