Lower Extremity

Question 1

Gastroc

Answer 1

Origin: Medial head: posterior surface of distal femur just superior to medial con- dyle;
Lateral head: upper posterolateral surface of lateral femoral condyle

Insertion: Via calcaneal tendon, to posterior surface of calcaneus

Innervation: S1 - S2 Tibial nerve

Function: Plantarflexes foot and flexes knee

Question 2

Soleus

Answer 2

Origin: Soleal line and medial border of tibia; posterior aspect of fibula head and adjacent surfaces of neck and proximal shaft; tedinous arch between tibial and fibular attachments

Insertion: Via calcaneal tendon, to posterior surface of calcaneus

Innervation: S1 - S2 Tibial nerve

Function: Plantarflexes the foot

Question 3

Tibialis Anterior

Answer 3

Origin: Lateral surface of the tibia and adjacent interosseous membrane

Insertion: Medial and inferior surfaces of medial cuneiform and adjacent surfaces on base of first metatarsal

Innervation: L4 - L5 Deep fibular nerve

Function: Dorsiflexion of foot and ankle joint; inversion of foot; dynamic support of medial arch of foot

Question 4

EDL

Answer 4

Origin: Proximal one-half of me- dial surface of fibula and related surface of lateral tibial condyle

Insertion: Via dorsal digital expansions into bases of distal and middle phalanges of lateral four toes

Innervation: L5-S1 Deep fibular nerve

Function: Extension of lateral four toes and dorsiflexion of foot

Question 5

EHL

Answer 5

Origin: Middle 1⁄2 of medial surface of fibula and adjacent surface of interosseous membrane

Insertion: Dorsal surface of base of distal phalanx of great toe

Innervation: L5-S1 Deep Fibular nerve

Function: Extension of great toe and dorsiflexion of foot

Question 6

Fibularis Longus

Answer 6

Origin: Upper lateral surface of the fibula, head of fibula, and occasionally the lateral tibial condyle

Insertion: Undersurface of lateral sides
of distal end of medial cuneiform and base of first metatarsal

Innervation: L5 - S1- S2 Superficial fibular nerve

Function: Eversion and plantarflexion of foot. Supports arches of foot

Question 7

Fibularis Brevis

Answer 7

Origin: Lower two-thirds of lateral surface of shaft of fibula

Insertion: Lateral tubercle base of 5th metatarsal

Innervation: L5 - S1- S2 Superficial fibular nerve

Function: Eversion of foot