Posterior and Anterolateral Leg

Question 1

What lies between the medial and lateral tubercle of the talus

Answer 1

Groove for flexor hallucis longus tendon

Question 2

Navicular tuberosity is attachment for

Answer 2

Tibialis posterior

Question 3

Superficial posterior group of leg includes

Answer 3

Gastrocnemius- most superficial
Soleus - triceps surae
Plantaris

Question 4

Deep posterior group of leg includes

Answer 4

Popliteus
Flexor hallucis longus
Flexor digitorum longus
Tibialis posterior

Question 5

Tibial nerve and posterior tibial vessels are deep to what

Answer 5

Transverse crural intermuscular septum

Question 6

Insertion for gastrocnemius

Answer 6

Posterior surface of calcaneus via tendo calcaneus (achilles tendon)

Question 7

Function of gastrocnemius

Answer 7

Plantar flexion and flexes leg at knee joint

Question 8

Soleus attachments, function, forms what big muscle with gastrocnemius

Answer 8

Soleal line of tibia
Posterior head of fibula/superior 1/4 of posterior fibula
Inserts into posterior calcaneus via tendo calcaneus
Forms triceps surae with gastrocnemius (these form the calf prominence)
Plantarflexion

Question 9

Plantaris origin, insertion, function,

Answer 9

Small, sometimes absent muscle
O: Lateral end of lateral supracondylar line
I: posterior calcaneus via calcaneal tendon
Weak plantarflexion and leg flexion
Proposed to be a proprioceptive organ for foot position because of its high density of proprioceptive receptors

Question 10

Long tendon of plantaris useful for

Answer 10

Commonly used in reconstructive surgery of hand tendons
Possibility of rupture during violent ankle movements, common in basketball players/sprinters/ballet dancers
Pain may be so severe that you cant bare weight

Question 11

Popliteus description, attachments, functions

Answer 11

Deep to plantaris, forms inferior floor of popliteal fossa
O- posterior tibia superior to soleal line
I- lateral surface of lateral femoral condyle
Unlocks extended leg by laterally rotating femur on a stationary tibia
Also flexes leg weakly

Question 12

Flexor hallucis longus description, attachments, function

Answer 12

Lies deep to soleus, largest posterior muscle
O- inferior 2/3 of posterior fibula
I-Base of distal phalanx of great toe
Tendon crosses deep to FDL tendon in sole of foot
Flexes great toe and plantarflexion

Question 13

Flexor digitorum longus description, attachments, function

Answer 13

Deep to soleus and posterior to tibia
Tendon passes deep to tibialis posterior, then diagonally in sole of foot superficial to FHL tendon
O- posterior tibia superior to soleal line
I- distal phalanx of lateral 4 digits
Flexes lateral 4 digits and plantarflexes foot

Question 14

Tibialis posterior description, attachments, function

Answer 14

Deepest posterior crural muscle, lies b/w FDL and FHL
Tendon passes anterior to FDL
O- interosseous membrane, posterior tibia, posteromedial fibula
I- Navicular tuberosity, cuneiforms, 2-4 metatarsals
Inversion, plantarflexion of foot

Question 15

What nerve supplies all posterior compartment muscles

Answer 15

Tibial nerve

Question 16

Tibial nerve path

Answer 16

Passes with posterior tibial vessels deep to soleus and posterior to tibialis posterior
Leaves posterior compartment by passing deep to flexor retinaculum b/w medial malleolus and calcaneus
Ends by dividing into medial and lateral plantar nerves

Question 17

Posterior tibial artery path

Answer 17

Begins near inferior border of popliteus deep to soleus
Gives rise to fibular artery
Passes inferomedially on posterior surface of tibialis posterior with tibial nerve
Runs deep to flexor retinaculum
Vascularizes posterior compartment
Ends by dividing into medial and lateral plantar arteriess

Question 18

Fibular artery path

Answer 18

Largest branch of posterior tibial artery
Begins inferior to distal border of popliteus
Descends obliquely towards fibula, usually under FHL
Ends by giving off a perforating branch as well as terminal lateral malleolar (anastomosis with anterior lateral malleolar) and calcaneal branches (supplies heel)
Vascularizes posterior and lateral compartments

Question 19

Crural fascia

Answer 19

Continuous with fascia lata
Covers leg muscles
Thickens distally to form extensor retinaculum

Question 20

Muscles in the anterior compartment include

Answer 20

Tibialis anterior
Extensor hallucis longus
Extensor digitorum longus
Fibularis tertius

Question 21

Primary functions of anterior leg muscles

Answer 21

Toe extension, foot dorsiflexion

Question 22

Tibialis anterior description, attachments, function

Answer 22

Long thick muscle on anterolateral tibial
O- Lateral tibial condyle and superolateral half of tibia
I- medial surface of first/medial cuneiform and first metatarsal base
Dorsiflexes and inverts foot

Question 23

Extensor digitorum longus attachments and function

Answer 23

O- Lateral tibial condyle, anterior fibular surface, interosseous membrane
I- each of four tendons forms extensor expansion of dorsum of lateral four proximal phalanges that divide into two lateral slips (attach to distal phalanx) and one central slip (attach to middle phalanx)

Question 24

Fibularis tertius description, attachments, function

Answer 24

Fuse with digitorum longus proximally
Tendon does not attach to digit
Variably present
O- anteroinferior fibular surface
I- dorsum of fifth metatarsal base
Dorsiflexion and eversion of foot

Question 25

Extensor hallucis longus description, attachments, function

Answer 25

Lateral to tibialis anterior O- anteromedial fibular surface and Int. membrane, medial to proximal attachment of extensor digitorum longus I- base of distal phalanx of hallux Extends big toe and dorsiflexes ankle

Question 26

Deep fibular nerve

Answer 26

One of two terminal branches of common fibular N. Begins b/w fibula and fibularis longus muscle Runs inferomedially w/anterior tibial vessels between tibialis anterior and EHL. Ends in medial and lateral terminal branches on dorsum of foot

Question 27

Deep fibular nerve supplies

Answer 27

Anterior compartment muscles Ankle joint and metacarpal phalangeal joints Dorsal intrinsic foot muscles Skin b/w first and second digits

Question 28

Anterior tibial artery path

Answer 28

Arises from popliteal artery Begins near inferior border of popliteus muscle, tibial tuberosity is approximate branch point of tibial artery into ant/posterior branches Passes anteriorly over interosseous membrane Descends of anterior surface of IO membrane b/w EHL and TA muscles with deep fibular nerve Ends at ankle b/w malleoli to become dorsalis pedis artery

Question 29

Lateral compartment of leg contains

Answer 29

Fibularis longus | Fibularis brevis

Question 30

Fibularis longus description, attachments, function

Answer 30

Extends from fibular head to sole of foot Superficial to fibularis brevis O- head and superolateral 2/3 of fibula Passes inferior just posterior to lateral malleolus Runs obliquely and distally across sole of foot to attach distally to first metatarsal and medial cuneiform bone Eversion and plantarflexion

Question 31

Cuboid sulcus

Answer 31

Cuboid is most lateral bone in distal row of tarsus | Sulcus is a groove for the fibularis longus

Question 32

Fibularis brevis description, attachments, function

Answer 32

``` Deep to fibularis longus O- inferolateral 2/3rds fibula Descends posterior to lateral malleolus I- dorsal surface of tuberosity on lateral side of 5th metatarsal Eversion and plantarflexion ```

Question 33

Superficial fibular nerve description/path

Answer 33

One of the two terminal branches of common fibular N. Begins b/w fibularis longus and fibula Descends b/w fibular muscles and lateral to EDL Becomes superficial in distal third of leg

Question 34

Superficial fibular nerve supplies

Answer 34

Anteroinferior leg Nearly entire dorsal surface of foot Most of dorsal aspects of digits

Question 35

Common fibular nerve injury

Answer 35

Results in paralysis of all anterior/lateral crural muscles Causes foot drop If leg is swung strongly forward the foot strikes with a clop noise Loss of sensation along anterolateral leg and dorsum of foot

Question 36

Arterial supply to lateral compartment

Answer 36

Branches that pass anteriorly from the fibular artery The one compartment without a distinct arterial branch accompanying the compartment nerve Fibular artery is largest branch of posterior tibial artery

Question 37

Shin splints

Answer 37

Due to repetitive microtrauma of tibialis anterior Inducing small tears to periosteum over tibia, and/or tears to overlying deep fascia Is a mild form of compartmental syndrome (swelling of tibialis anterior due to repetitive ground reaction force)