Rockwood Adults CH64

2826

SECTION FOUR • Lower Extremity

hallucis lies the deep peroneal nerve and the dorsalis pedis artery, and then the tendons of extensor digitorum longus and peroneus tertius. The tendons, and the superficial peroneal nerve which lies in the subcutaneous plane, can often be seen and palpated with the ankle and toes maximally dorsiflexed. Laterally, the peronei lie deep to the peroneal retinaculum immediately posterior to the fibula. The retinaculum may be ruptured here resulting in tendon subluxation. The superfi- cial peroneal nerve emerges from the deep fascia at a variable point in the distal third of the leg before dividing: A substantial branch has been reported to lie within 5 mm of the fibula in 50% cases when measured at 10 cm from the lateral malleolar tip and in 20% cases at 5 cm from the tip, 163 leaving it vulner- able to injury in the lateral approach to the fibula. Also in the subcutaneous plane, the sural nerve lies in a variable position approximately two-thirds of the way between the distal fibula and the tendo Achilles. Medially, a number of structures run posterior to the medial malleolus under the lacinate ligament,

Anterior tibiofibular ligament Anterior

Posterior talofibular ligament

talofibular ligament

Fibulocalcaneal ligament

Figure 64-5.  The lateral ligamentous complex of the ankle and its individual components.

Saphenous nerve

Superficial peroneal nerve

Flexor digitorum longus

Tibialis posterior Posterior tibial artery Tibial nerve

Saphenous vein

Tibialis anterior

Flexor hallucis longus

Extensor digitorum longus

Tibialis anterior Extensor hallucis longus

Deep peroneal nerve Anterior tibial artery

A

Peroneus tertius tendon

Sural nerve

Lesser saphenous vein

Peroneus longus

Peroneus tertius

Peroneus brevis

Superior retinaculum

B

C

Figure 64-6.  A: Structures crossing the medial ankle. B: Structures crossing the anterior ankle. C: Structures crossing the lateral ankle.