Ankle and Foot

Ankle Sprain

The ankle is stabilized laterally by the anterior inferior tibiofibular, anterior talofibular, posterior talofibular, and calcaneofibular ligaments.

Lateral ankle sprain, which is most often due to inversion of a plantar-flexed foot. The lateral ankle ligaments are weaker and are injured more often than the medial ligaments. The most common ankle sprains involve only the anterior talofibular ligament and present with pain and ecchymosis at the anterolateral aspect of the ankle.

Basics:

The gastrocnemius with the soleus muscle dose the bulk of the work with respect to plantar flexion of the ankle. The plantaris is the third muscle which provides a small amount of additional power. All three muscles in this group are supplied by the tibial nerve, a branch of the sciatic nerve.

Peroneus brevis and longus are responsible for ankle joint eversion and are supplied by the superficial fibular nerve.

Tibialis anterior -> ankle dorsiflexion; supplied by the deep fibular nerve

Acute Ankle and Foot Injury

Ottawa Rules to consider X-ray requirement

An ankle X-Ray series is only required if there is any pain in the malleolar zone and...

Bone tenderness at the posterior edge or tip of the lateral malleolus (A)

OR

Bone tenderness at the posterior edge or tip of the medial malleolus (B)

OR

An inability to bear weight both immediately and in the emergency department for four steps

A foot X-Ray series is only required if there is any pain the midfoot zone and...

Bone tenderness at the base of the fifth metatarsal (C)

OR