ORIGINS, INSERTIONS AND ACTIONS BY TAELAR SHELTON, MS, ATC, AT/L Ankle Muscles ORIGINS, INSERTIONS AND ACTIONS BY TAELAR SHELTON, MS, ATC, AT/L

Origins of muscles Origins are the flixed attachment point of muscles in the bone (this bone doesn’t move when the action of the muscle is performed)

Insertions of muslces Insertions is the attachment point of the tendon into the bone that moves when the action of the muscle is performed

Actions of muslces Actions- what the muscles does

Tibialis Anterior O- lateral condyle and upper 2/3rds of tibia I- by tendon into interior surface of medial cuneiform and 1st metatarsal bone A- prime mover of dorsiflexion inverts foot; assists in supporting medial longitudinal arch of foot

Extensor Digitorum O- lateral condyle of the tibia; proximal ¾ of the fibula; interosseous membrane I- second and third phalanges of toes 2-5 via extensor expansion A- dorsiflexes foot; prime mover of toe extension

Peroneus Brevis O- distal fibula shaft I- by tendon running behind lateral malleolus to insert on the proximal end of the 5th metatarsal A- plantar flexes and everts the foot

Extensor Hallucis Longus O- Anteriomedial fibula shaft and interosseous membrane I- tendon inserts on the distal phalnx of the great toe A- extension of the great toe; dorsiflexion

Peroneus Tertius O- distal anterior surface of the fibula; interosseous membrane I- Tendon passes anterior to lateral malleolus and inserts on the dosum of the 5th metatarsal A- dorsiflexes and everts the foot

Peroneus Longus O- head and upper portion of fibula I- by long tendon that curves under the foot to 1st metatarsal and medial cuneiform A- plantarflexes and everts foot; helps keep foot flat on the ground

Tibialis Posterior O- extensive origin from superior tibia and fibula and the interosseous membrane I- tendon passes behind medial malleolus and under the arch of the foot; inserts into several tarsals and metatarsals 2-4 A- prime mover of foot inversion; plantar flexes ankle, stabilizes medial longitudinal arch

Flexor Digitorum O- Posterior tibia I- tendon runs behind medial malleolus and splits to insert into distal phalanages of toes 2-5 A- plantar flexes and inverts foot; flexes toes; helps foot grip ground

Flexor Hallucis Longus O- middle part of the shaft of fibula; interosseous membrane I- tendon runs under foot to distal phalanx of great toe A- plantar flexes and inverts foot; flexes great toe at all joints; push off muscle during walking

Popliteus O- lateral condyle of femur I- proximal tibia A- flexes and rotates leg medially to unlock knee from full extension when flexion begins

Plantaris O- posterior femur above the lateral condyle I- via a long, thin tendon into the calcaneus or calcaneal tendon (achilles) A- assists in knee flexion and plantar flexion of foot

Soleus O- extensive cone shaped origin from the superior tibia, fibula and interossous membrane I- calcaneus via calcaneal tendon A- plantar flexes ankle; important locomotor and postural muscle during walking, running and dancing

Gastrocnemius O- by two heads from the medial and lateral condyles of the femur I- calcaneus via calcaneal tendon A- Plantar flexes foot when knee is extended; can flex the knee when the foot is dorsiflexed