0071643192.pdf

ORTHOPEDICS

Ankle Injuries

LATERALLIGAMENTOUSANKLEINJURY

■ Ankle inversions with lateral ankle sprains are far more common than

medial injuries (>90%).

■ The anterior talofibular ligament is the most commonly injured ligament,

followed by the calcaneofibular ligament and the posterior talofibular

ligament.

MECHANISM

Inversion with internal rotation of a plantar-flexed foot

DIAGNOSIS

■ Abnormalanterior drawer test(ankle plantar flexed 10° from neutral,

knee slightly flexed, one hand on base of tibia, other hand cups the heel,

instability when pulling anteriorly) with anterior talofibular ligament

rupture

■ Abnormaltalar tilt test(>5° rotation with inversion) with presence of both

anterior talofibular andcalcaneofibular ligament ruptures

MEDIALLIGAMENTOUSANKLEINJURY

Far less common because the medial deltoidligament is much stronger

MECHANISM

Eversion and external rotation of foot

DIAGNOSIS

Significant tenderness and swelling at the level of and distal to the medial

malleolus.

COMPLICATION

Sometimes associated with a proximal fibula fracture, ie, Maisonneuve fracture

DISTALTIBIOFIBULARSYNDESMOTICLIGAMENTINJURIES

MECHANISM

Dorsiflexion and eversion of foot with an axial load

DIAGNOSIS

Positive squeeze testin which the examiner firmly grasps the patient’s lower

leg and “squeezes” the distal tibia and fibula together, causing pain if the

injury is present

ANKLESPRAINS

First-Degree Ankle Sprain

DIAGNOSIS

■ Able to bear weight

■ No joint instability