Lateral Ankle Sprain

Mechanism

• Inversion with plantarflexion (and internal rotation), for example landing on another player’s foot or an uneven surface.
• Order of injury: ATFL first (isolated in about 70%), then CFL, then PTFL.
• Sports: basketball, football, netball, volleyball, trail running.
• Strongest risk factor: previous sprain. Others: poor proprioception, no external support, inadequate prior rehab.

Presentation

• Lateral ankle pain, rapid swelling, bruising over 24 to 48 hours
• Tenderness over ATFL (anterolateral) or CFL (inferolateral)
• Anterior drawer tests ATFL. Inversion stress (talar tilt) tests CFL. Both are more reliable after acute pain settles.

Exclude fracture: Ottawa Ankle Rules

X-ray if there is bony tenderness at the posterior edge or distal 6 cm of either malleolus, the navicular, or the base of the 5th metatarsal, or inability to weight-bear four steps immediately and in clinic.

The ROAST consensus advises against routine imaging without these indicators.

Management

Functional treatment beats immobilisation for grades I to II.

1. POLICE or PEACE and LOVE: protection, optimal loading, ice, compression, elevation.
2. Early functional rehabilitation: early protected weight-bearing, range of motion, then strengthening.
3. Neuromuscular and balance training: the mainstay of preventing recurrence.
4. Brace or tape during return to sport.
5. Grade III: a short period of immobilisation may precede functional rehab.
6. Surgery: rarely acute. Reserve for chronic instability that fails rehabilitation.

Return to play

• Grade I: 1 to 2 weeks. Grade II: 3 to 6 weeks. Grade III: longer.
• Criteria, not time: full range of motion, no pain, adequate strength and balance.

References

1. Delahunt et al., ROAST consensus, Br J Sports Med 2018, doi:10.1136/bjsports-2017-098885
2. Gribble et al., International Ankle Consortium, Br J Sports Med 2016, doi:10.1136/bjsports-2016-096188

Related

• Chronic Ankle Instability
• Peroneus (Peroneal) Tendinopathy
• ISMEC Return to Play Protocol