Ankle Sprain: A Comprehensive Review for Clinicians and Patients
Ankle sprains are among the most common musculoskeletal injuries encountered in both emergency departments and primary care settings. Despite their frequency, improper management can lead to chronic instability, recurrent sprains, and long-term disability. This evidence-based review provides a detailed overview of ankle sprain classification, diagnosis, treatment protocols, rehabilitation strategies, and prevention—tailored for both orthopedic surgeons and patients.
What Is an Ankle Sprain?
An ankle sprain occurs when the ligaments supporting the ankle are stretched or torn due to sudden twisting, rolling, or turning of the foot beyond its normal range of motion. The majority (85%) involve the lateral ligament complex, particularly the anterior talofibular ligament (ATFL).
Classification of Ankle Sprains
Ankle sprains are classified by severity and anatomical involvement:
| Grade | Ligament Damage | Symptoms | Recovery Time |
|---|---|---|---|
| Grade I | Mild stretching; microtears | Mild pain, minimal swelling, no instability | 1–2 weeks |
| Grade II | Partial tear | Moderate pain, swelling, bruising, mild instability | 3–6 weeks |
| Grade III | Complete rupture | Severe pain (may subside quickly), significant swelling, bruising, mechanical instability | 6–12 weeks (may require bracing or surgery) |
Types of Ankle Sprains
| Type | Frequency | Mechanism | Ligaments Involved |
|---|---|---|---|
| Inversion (Lateral) Sprain | ~85% | Foot rolls inward | ATFL > CFL > PTFL |
| Eversion (Medial) Sprain | ~5% | Foot rolls outward | Deltoid ligament |
| High Ankle (Syndesmotic) Sprain | ~10% | External rotation + dorsiflexion | Anterior inferior tibiofibular ligament (AITFL), interosseous membrane |
Clinical Diagnosis
Diagnosis begins with a thorough history and physical examination. Key questions include mechanism of injury, ability to bear weight, and prior ankle injuries.
Ottawa Ankle Rules (For Clinicians)
Use these evidence-based rules to determine if X-rays are needed:
- Pain in the malleolar zone AND
- Any of the following:
- Bone tenderness at the posterior edge or tip of the lateral malleolus
- Bone tenderness at the posterior edge or tip of the medial malleolus
- Inability to bear weight for four steps immediately after injury and in the ER
If none apply, fracture is unlikely (sensitivity >99%).
Imaging Modalities
- X-ray: Rule out fractures (e.g., avulsion, osteochondral lesions).
- Ultrasound: Dynamic assessment of ligament integrity; cost-effective.
- MRI: Reserved for chronic instability, suspected osteochondral defects, or syndesmotic injuries.
Treatment Strategies
Acute Phase (First 72 Hours): POLICE Protocol
Modern guidelines have replaced RICE with POLICE:
- Protection: Use brace or tape if needed.
- OL (Optimal Loading): Early controlled movement > strict rest.
- Ice: 15–20 min every 2–3 hours.
- Compression: Elastic bandage to reduce swelling.
- Elevation: Above heart level when possible.
Rehabilitation (Weeks 1–6)
Structured physiotherapy is critical to prevent chronic issues:
- Range of Motion (ROM): Alphabet tracing with toes, ankle circles.
- Strengthening: Resistance band exercises (inversion, eversion, dorsiflexion, plantarflexion).
- Proprioception Training: Single-leg stance, wobble board, balance pads.
- Functional Training: Sport-specific drills before return-to-play.
Surgical Considerations
Surgery is rarely needed for acute sprains but may be considered for:
- Chronic ankle instability (>6 months of failed conservative treatment)
- Grade III syndesmotic injuries with diastasis
- Associated osteochondral lesions or peroneal tendon tears
Prevention of Recurrent Sprains
Up to 40% of patients develop chronic symptoms. Prevention includes:
- Neuromuscular training programs (e.g., FIFA 11+)
- Ankle taping or semi-rigid braces during high-risk activities
- Continued proprioception exercises even after recovery
Frequently Asked Questions (FAQs)
Q: Should I use heat or ice for my ankle sprain?
A: Use ice during the first 72 hours to reduce inflammation. Avoid heat—it can increase swelling. After day 3, gentle heat may help with stiffness during rehab.
Q: Can I walk on a sprained ankle?
A: If you can bear weight without severe pain, walking is encouraged (with support if needed). Complete immobilization delays recovery. Use crutches only if unable to walk comfortably.
Q: How long until I can return to sports?
A: Grade I: 1–2 weeks; Grade II: 3–6 weeks; Grade III: 6–12 weeks. Return should be based on functional criteria—not time—including full ROM, strength, and balance.
Q: Do I need an MRI for every ankle sprain?
A: No. Most sprains are diagnosed clinically. MRI is reserved for persistent pain, instability, or suspicion of cartilage injury after 6–8 weeks of rehab.
Q: Are ankle braces effective?
A: Yes—especially for athletes with prior sprains. Semi-rigid braces reduce re-injury risk by up to 70% without impairing performance.
Key Takeaways for Doctors
- Apply Ottawa Ankle Rules to avoid unnecessary imaging.
- Emphasize early mobilization over immobilization.
- Prescribe structured rehab—not just rest.
- Screen for risk factors of chronic instability (e.g., hypermobility, poor proprioception).
Key Takeaways for Patients
- Don’t ignore a “simple” sprain—improper healing leads to long-term problems.
- Start gentle movement within 48 hours.
- Complete your rehab program—even if pain subsides.
- Use supportive footwear and consider a brace when returning to activity.
References
- Waterman BR, Owens BD, Davey S, et al. The epidemiology of ankle sprains in the United States. J Bone Joint Surg Am. 2010;92(13):2279–2284.
- Gribble PA, Hertel J, Plisky P. Using the Star Excursion Balance Test to assess dynamic postural-control deficits and outcomes in lower extremity injury: a literature and systematic review. J Athl Train. 2012;47(3):339–357.
- Doherty C, Bleakley C, Delahunt E, Holden S. Treatment and prevention of acute and recurrent ankle sprain: an overview of systematic reviews with meta-analysis. Br J Sports Med. 2017;51(2):113–125.
- Stiell IG, Greenberg GH, McKnight RD, et al. Decision rules for the use of radiography in acute ankle injuries. JAMA. 1993;269(9):1127–1132.
- American Academy of Orthopaedic Surgeons (AAOS). Ankle Sprains. Clinical Practice Guideline. 2022.