What are the boundaries of the femoral triangle?
• Proximally—inguinal ligament.
• Medially—adductor longus.
• Floor—iliacus, psoas, pectineus, and adductor longus.
Which muscles of the lower extremity are located in the superficial posterior compartment? What is the innervation and function of each? Superficial posterior compartment?
• Gastrocnemius, innervated by posterior tibial nerve, functions in plantar flexion.
• Plantaris (as for gastrocnemius).
• Soleus (as for gastrocnemius).
Deep posterior compartment?
• Flexor hallucis longus/posterior tibial nerve/toe flexion.
• Tibialis posterior/posterior tibial nerve/inversion and plantar flexion of ankle.
• Flexor digitorum longus (as for flexor hallucis longus).
• Peroneus brevis/superficial peroneal nerve/ankle eversion.
• Peroneus longus (as for brevis).
• Tibialis anterior/deep peroneal nerve/ankle dorsiflexion.
• Extensor digitorum longus/deep peroneal nerve/toe extension.
• Extensor hallucis longus/deep peroneal nerve/toe extension.
• Peroneus tertius/deep peroneal nerve/ankle eversion and weak dorsiflexion.
In which compartments do the trifurcated arteries travel in the lower extremity?
Anterior tibial artery—anterior compartment.
Posterior tibial artery—deep posterior compartment.
Peroneal artery—deep posterior compartment.
What nerve may accompany the lesser saphenous vein and what does it innervate?
The sural nerve provides sensation to the skin over the posterolateral lower extremity, the lateral heel, and the lateral border of the foot. It is found between the Achilles tendon and lateral malleolus and up to 25 cm can be harvested.
The plantar surface of the foot may be divided into four layers. Which muscles may be found in the most superficial layer?
• Flexor digitorum brevis.
• Abductor hallucis.
• Abductor digiti quinti.
What nerves provide sensation to the foot and what are their respective dermatomes?
• Posterior tibial nerve—plantar midfoot and heel
• Sural nerve—lateral midfoot
• Saphenous nerve—medial ankle
• Superficial peroneal nerve—dorsal distal foot
• Deep peroneal nerve—first web space
Which tendon of the lower extremity is the preferred donor for grafting and which nerve is most at risk during harvest?
Plantaris tendon. It is present in approximately 80% of lower limbs. Dissection begins just posterior to the medial malleolus, placing the posterior tibial nerve at risk.
What findings are indicative of compartment syndrome?
• Palpable firmness of compartment, pallor, pain on passive extension is compartment-specific:
• Anterior: pain on passive plantar flexion and foot eversion, toe flexion.
• Lateral: pain on passive dorsiflexion and foot inversion.