Lab 7 - Module 2 - Posterior Compartment of the Leg: Page 1 of 3

READINGS:

Gray's Anatomy for Students (Fourth Edition): Pages: 615-624

Deep Posterior Compartment of the Leg

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Boundaries of the Deep Postior Compartment are the tibia, fibula, and interosseous membrane anteriorly and the transverse intermuscular septum posteriorly.

Muscular components of the deep posterior compartment are:

Begin with a view of the Posterior Leg.

Add the Posterior Tibialis muscle.

Origin - Posterior surface of the interosseous membrane, posterior surface of the tibia, posteiror surface of the fibula

Insertion - Tuberosity of the navicular bone of the foot, may send slips to the 3 cunieforms, cuboid and 2nd-4th metatarsal bones

Innervation - Tibial Nerve

Action - Plantarflexion of the ankle, inversion of the foot

Add the Flexor Digitorum Longus muscle.

Origin - Posterior surface of the tibia and the fascia of posterior tibialis

Insertion - Base of the distal phalanx of the four lateral toes

Innervation - Tibial Nerve

Action - Flexes the four lateral toes, assists with plantar flexion

Add the Politeal Artery.

Add the Posterior Tibial Artery which is the major blood supply of the compartment is from the posterior tibial artery.

Add the Fibular Artery which is, at its proximal edge, seen on the surface of the FHL, but then disappearing from view as it passes into the muscle and remains there until it passes through the distal interosseus membrane to anastomose with the anterior tibial artery.

Add the Tibial Nerve which innervates the muscles of the posterior compartment. The tibial nerve will be seen at the ankle joint as it travels into the sole of the foot where it will continue to give innervation.

	If the pain is in the “calf” region, how do you explain the numbness and tingling in the plantar aspect of her foot?
Compose an answer to help focus your study of this module.

Add the Flexor Hallicus Longus muscle.

Origin - Inferior 2/3rds of the posterior fibula and the inferior part of the interosseous membrane

Insertion - Base of the distal phalanx of the great toe

Innervation - Tibial Nerve

Action - Flexes the great toe, assists with plantar flexion