Anatomy lecture27-10-2008

Anterior and lateral compartment of leg

Bones of leg

• Bones of leg:• Tibia• fibula

Muscles of the anterior leg

• Tibialis anterior• Extensor digitorum longus• Extensor hallucis longus• Peroneus tertius

Anterior leg

• Cross sectionof anterior leg

Tibialis anterior

Origin:Shaft of the tibia

interosseous membrane

Insertion:Medial cuneiform and base ofFirst metatarsal.

Nerve:Deep peroneal nerve

Action:Extend the footHelp to maintain the medial longitudinalArch of foot

Extensor digitorum longus

• Origin:Shaft of fibula Interosseous membrane

• Insertion:Extensor expansion of latral four toes

Nerve: deep peroneal nerve

Action:Extends toes

Extensor hallucis longus

• Origin:Shaft of fibula Interosseous membrane

• Insertion: base of distal phalanxOf big toeNerve:Deep peroneal nerveAction:Extend big toeDorsoiflexes foot

Peroneus tertius muscle

• OriginShaft of fibula Interosseous membrane• Insertion:Base of fifth metatarsal• Nerve:Deep peroneal nerve• Action:Dorsiflexes footEvertion at subtalar and tarsal joint

Innervations and blood supply of anterior leg

• Deep peroneal nerveIs a branch from Common peroneal nerve.Anterior tibial artery is a branch of popliteal artery

Muscles of the lateral leg

• Peroneus longus• Peroneus brevis

Peroneus longus muscle• Origin:• Shaft of fibula• Insertion:Base of first metatarsalMedial cuneiform• Nerve:Superficial peroneal nerve• Action:Planter flexes,eversion of footSupport lateral longitudinalarchThis the only muscle which crossesThe planter surface to maintain Transverse arch of foot

Peroneus brevis muscle

• Origin:• Shaft of fibula

• Insertion:Base of fifth metatarsalBoneNerve :Superficial peroneal nerveAction:Planter flexes footHold up lateral longtidunal arch

Thank you

Dr. kumarAssociate professor

Dr. mashairinstructor