Lecture 9 - Leg

Question 1

Bones of the leg

Answer 1

Tibia

Fibula

(Femur)

Question 2

Tibia

Answer 2

Most common long bone to be broken

Relatively poor blood supply

Anteromedial surface is bare

Soleal line on posterior surface

Question 3

Fibula

Answer 3

Lateral malleolus important in ankle stability

Site for muscle attachment

Question 4

Tibia Structures- Proximal

Answer 4

Anterior:

• medial and lateral condyles
• tuberosity
• tubercles of intercondylar eminence

Posterior:

• medial and lateral condyles
• tubercles of intercondylar eminence
• articulate facet for fibula
• soleal line

Question 5

Tibia Structures- Distal

Answer 5

Anterior:
-medial malleolus

Posterior:

• fibular notch
• soleal line

Question 6

Fibular Structures- Proximal

Answer 6

Head

Apex

Articulate Surface for lateral condyle of tibia

Question 7

Fibular Structures- Distal

Answer 7

Lateral malleolus (with articulate facet for talus)

Question 8

Does the tibia or the fibula contain an interosseous border?

Answer 8

BOTH

• face each other when two bones articulate
• site of attachment of interosseous membrane

Question 9

Crucial Fascia

Answer 9

Continues with fascia latae

Fascia forms retinacula in foot

Question 10

Fascia Latae

Answer 10

Attachment to anterior and medial borders of tibia

Continuous with periosteum

Leaves bare area

Question 11

Superior (extensor) retinaculum

Answer 11

• proximal to malleoli

- binds tendons in anterior crural compartment

Question 12

Inferior (extensor) retinaculum

Answer 12

Y shaped

Question 13

Flexor retinaculum

Answer 13

Binds tendons of the deep posterior compartment

Question 14

Superior/Inferior perineal retinacula

Answer 14

Bind tendons of lateral crural compartment

Question 15

Cutaneous Nerves of Sup. Post. Compartment

Answer 15

Lateral sural cutaneous nerve

Medial sural cutaneous

Sural nerve runs with lesser saphenous vein

Question 16

Muscles of Sup. Post. Compartment

Answer 16

Gastrocnemius, plantaris, soleous, triceps surae, common insertion

Question 17

Gastrocnemius

Answer 17

• Crosses both knee and ankle joint
• Two heads form inferior boundaries of the popliteal fossa
• Lateral head may have a sesamoid bone: •Fabella

Question 18

Plantaris

Answer 18

•May be absent •Tendon may be used for hand surgery

Question 19

Soleus

Answer 19

•Broad multipennate muscle •Unijoint muscle

Question 20

Triceps surae

Answer 20

Soleus + two heads of gastrocnemius

Question 21

common insertion

Answer 21

Calcaneus via tendocalcaneus (Achilles tendon)

Question 22

Tibial Nerve

Answer 22

• Supplies all muscles in posterior compartment
• Divides into medial and lateral plantar nerves inferior and posterior to medial malleolus
• Gives off medial sural cutaneous nerve
• Joins with communicating branch of common peroneal (fibular) nerve to form:
• Sural nerve: •Cutaneous

Question 23

Posterior tibial artery

Answer 23

•Largest branch of popliteal artery
Provides both Superficial and Deep Comp
•Divides into medial and lateral plantar arteries deep to origin of abductor hallucis muscle

Question 24

Peroneal (fibular) artery

Answer 24

• Most important branch of posterior tibial artery
• Supplies lateral compartment and popliteus muscles
• Supplies other muscles in posterior compartment

Question 25

Muscles of the Deep Posterior Compartment

Answer 25

Popliteus, flexor digitorum longus, flexor hallicus longus, tibialis posterior

Question 26

Popliteus

Answer 26

•Lies in floor of popliteal fossa •Flexes and rotates knee

Question 27

Flexor digitorum longus

Answer 27

* Tendon passes posterior to medial malleolus and to tendon of tibialis posterior * Plantarflexes foot at ankle joint

Question 28

Flexor hallucis longus

Answer 28

* Tendon occupies groove on posterior surface of talus: * Continuous with groove on plantar surface of sustentaculum tali. * Tendon passes posterior to medial malleolus. * Tendon passes between two sesamoid bones. * Push-off muscle for walking, jumping, running

Question 29

Tibialis posterior

Answer 29

* Functions in plantar flexion and foot inversion | * Helps to maintain medal longitudinal arch

Question 30

Tibialis nerve

Answer 30

supplies deep post. compartment

Question 31

Muscles of the anterior compartment

Answer 31

Tibialis anterior, extensor digitorum longus, peroneus (filbularis) terius, extensor hallicus longus

Question 32

Tibialis Anterior

Answer 32

* Lateral to crest of tibia * Foot dorsiflexion and inversion * L4-L5 * Paralysis results in foot drop

Question 33

Extensor digitorum longus

Answer 33

* Four tendons of insertion: * Each tendon inserts on an extensor expansion similar to arrangement in hand. * Toe extension at MTP and also dorsiflexion

Question 34

Peroneus (fibularis) tertius

Answer 34

* Part of extensor digitorum longus * Sometimes missing * Foot dorsiflexion an eversion

Question 35

Anterior compartment functions

Answer 35

toe extension | ankle dorsiflexion

Question 36

deep peroneal (fibular) nerve

Answer 36

Innervation of anterior compartment •L4-5 to tibialis anterior. •L5-S1 for remaining muscles. •Runs deep to extensor digitorum longus. •Accompanies anterior tibial artery between extensor hallucis longus and tibialis anterior muscles.

Question 37

Anterior tibial artery

Answer 37

Blood Supply to anterior compartment •Smaller terminal branch of popliteal artery •Begins at inferior border of popliteus muscle •Becomes dorsalis pedis artery at ankle joint

Question 38

Muscles of the Lateral Compartment

Answer 38

Peroneus (fibularis) longus, Peroneus (fibularis) brevis

Question 39

Peroneus (fibularis) longus:

Answer 39

* More superficial of the two * Easily palpated * Its tendon uses lateral malleolus as a pulley * Tendon crosses sole of foot and inserts on first metatarsus and cuneiform * Helps to maintain transverse and longitudinal arches of the foot

Question 40

Peroneus (fibularis) brevis

Answer 40

* Deep to peroneus longus * Inserts on lateral tuberosity * Functions in plantar flexion and foot eversion

Question 41

Superficial peroneal (fibular) nerve:

Answer 41

•Deep to peroneus longus •Inserts on lateral tuberosit

Question 42

Blood supply of Lateral Compartment:

Answer 42

* No major arteries in lateral compartment | * Muscular branches arise from the peroneal artery: •Branch of posterior tibial

Question 43

Spinal cord levels of lat compartment

Answer 43

L5, S1-S2