II. Epidemiology
- Accounts for up to 10% of Ankle Sprains in high risk populations
- Most common sports associated with High Ankle Sprain
III. Mechanism
- Eversion and Rotation injury
- Hyper-dorsiflexion
IV. Anatomy
- Tibiofibular Syndesmosis injury
- Interosseous membrane (IM)
- Anterior Inferior tibiofibular ligament (AITF)
- Separation of Tibia from fibula
V. Symptoms
- Medial ankle pain
- Difficulty bearing weight
VI. Signs
- Minimal external signs of injury (e.g. swelling)
- Pain and Disability out of proportion with injury
- Ankle may feel spongy
- Ankle Squeeze Test positive
- Ankle External Rotation Test positive
- Crossed-Leg Test positive
- Point tenderness over anterior and proximal ankle
- Pain at distal tibiofibular joint
VII. Associated conditions
- Maisonneuve Fracture
- Proximal Fibula Fracture
- Palpate full length of fibula and tibia on exam
VIII. Imaging
-
Ankle XRay
- Tibiofibular clear space widening >6 mm indicates complete syndesmotic rupture
- Tibia-Fibula XRay
- Exclude Proximal Fibula Fracture (Maisonneuve Injury)
-
Ankle MRI
- Persistent Disability in an injury suggestive of High Ankle Sprain
IX. Management
- No early mobilization
- May require internal fixation
X. Prognosis
- More disabling than other Ankle Sprains
- May require 4-5 months to return to prior functional capacity
- Risk of ankle Degenerative Joint Disease
