2.6.5. ANAT LAB - Posterior Leg Compartments

Question 1

Name the muscles in the anterior compartment of the leg. (4)

What is this group of muscles called (i.e. what is their function)?

Answer 1

1) Tibialis anterior
2) Extensor digitorum longus
3) Extensor hallucis longus
4) Fibularis tertius

These muscles are referred to as the long extensors.

Question 2

Name the muscles in the lateral compartment of the leg. (2)

What is this group of muscles called (i.e. what is their function)?

Answer 2

1) Fibularis longus
2) Fibularis brevis

These muscles are called the evertors

Question 3

What are the two subcompartments of the posterior compartment of the leg called?

What separates them?

Answer 3

Deep and superficial

They are separated by the transverse intermuscular septum

Question 4

Name the muscles of the superficial posterior compartment. (3)

What is this group of muscles called?

Answer 4

1) Gastrocnemius
2) Soleus
3) Plantaris

The muscles of the posterior compartment are called the long flexors

Question 5

Name the muscles of the deep posterior compartment. (4)

What is this group of muscles called?

Answer 5

1) Popliteus
2) Flexor hallucis longus
3) Flexor digitorum longus
4) Tibialis posterior

The muscles of the posterior compartment of the leg are called the long flexors

Question 6

In what compartment of the leg would you be most worried about compartment syndrome, and why?

Answer 6

The deep posterior compartment because the muscles are tightly compacted; swelling in this area can cause compartment syndrome.

Question 7

List the structures that transit the space under the flexor retinaculum to the foot. (6)

Answer 7

1) Tibialis posterior tendon
2) flexor Digitorum posterior tendon
3) posterior tibial Artery
4) posterior tibial Vein(s)
5) tibial Nerve
6) flexor Hallucis longus tendon

(Tom, Dick, and A Very Nervous Harry)

Question 8

Which part of the foot is made up by the tarsus?

List the bones of the tarsus. (7)

Answer 8

The tarsus is the posterior/proximal foot.

1) Talus
2) Calcaneus
3) Cuboid
4) Navicular

5,6,7) Cuneiforms

Question 9

List three awesome facts about the talus bone.

Answer 9

1) The talus is gripped by two malleoli (the distal heads of the tibia and fibula)
2) The talus receives the weight of the body from the tibia
3) The talus is the ONLY tarsal bone with no muscular or tendinous attachments

Question 10

What bone is gripped by the malleoli of the distal heads of the tibia and fibula?

Answer 10

The talus

Question 11

Which bone receives the weight of the body from the tibia?

How and where does it transmit the weight after it is received from the tibia?

Answer 11

The talus receives the weight of the body from the tibia.

The talus transmits the weight to the calcaneus (heel) and the fore foot via an osseoligamentous hammock.

Question 12

Name the only tarsal bone with no muscular or tendinous attachments.

Answer 12

The talus

Question 13

The body of the talus rests on which bone?

Answer 13

The calcaneus

Question 14

Which is the largest, strongest bone in the foot?

Answer 14

The calcaneus

Question 15

Name the weight bearing prominence of the calcaneus.

Answer 15

The calcaneus tuberosity

Question 16

How many tubercles does the calcaneus have?

Which is the only one contacting the ground when standing?

Answer 16

3 tubercles - medial, lateral and anterior

The medial tubercle is the only one contacting the ground when standing.

Question 17

Name the bones of the midfoot. (5)

Answer 17

1) Navicular
2) Cuboid

3,4,5) Cunieform bones

Question 18

What is an important site for tendon attachments to help hold the medial foot (arch) off the ground?

Answer 18

Navicular tuberosity

Question 19

What is the most lateral bone of the distal tarsus bones?

Which tendon goes through the groove on the lateral and inferior surfaces of this bone?

Answer 19

The cuboid bone

The tendon of the fibularis longus muscle runs through the groove on the cuboid

Question 20

Which cuneiform bone articulates with the cuboid?

Answer 20

The lateral (third) cuneiform

Question 21

All cuneiform bones articulate with the _____1______ posteriorly and the base of its appropriate ______2_______ anteriorly.

Answer 21

1) Navicular
2) Metatarsal

Question 22

How many metatarsals are in a foot?

How are they numbered?

Which is the longest?

Shortest?

Answer 22

There are 5 metatarsals (but I made you think for a second, didn’t I?)

They are numbered from the medial side

The 2nd metatarsal is the longest

The 1st metatarsal is the shortest

Question 23

Where are the medial and lateral sesamoid bones located on the 1st metatarsal?

Answer 23

On the plantar surface of the head of the 1st metatarsal (they are embedded in the tendons passing along the plantar surface)

Question 24

What part of the foot are the tarsals in?

What part of the foot are the metatarsals and phalanges in?

Answer 24

The tarsals are in the posterior foot

The metatarsals & phalanges are in the anterior foot

Question 25

Each metatarsal has three parts. What are they?

Answer 25

The base, the shaft, and the head

Question 26

What separates the posterior foot from the anterior foot?

Answer 26

The oblique tarsometatarsal line formed by the tarsometatarsal joints.

Question 27

How many phalanges are there in a foot?

Each phalange has three parts. What are they?

Answer 27

You have 14 (exact same setup as the hand; thumb = great toe)

Each phalange has a base, shaft, and head.

Question 28

Name the specific parts of the bones involved in the tibiofibular joint.

What surrounds the joint?

Answer 28

The flat facet on the fibular head and a similar facet located posterolaterally on the lateral tibial condyle

The joint is surrounded by a tense joint capsule

Question 29

Communication between what two structures can allow inflammation to migrate from the popliteal joint to the tibiofibular joint?

How common is this communication?

Answer 29

Communication between the popliteal bursa and the synovial cavity of the tibiofibular joint

This happens about ~20% of the time.

Question 30

What is the tibiofibular syndesmosis?

Answer 30

A compound fibrous joint (fibrous union of the tibia and fibula via the interosseus membrane and the anterior, interosseus, and posterior tibiofibular ligaments (latter three make up the inferior tibiofibular joint)

Question 31

What forms the principal connection between the tibia and fibula?

Answer 31

The Interosseus tibiofibular ligament

Question 32

What is the function of the malleolar mortise?

What forms its three walls?

Answer 32

The Malleolar mortise is a square socket for the trochlea of the talus.

posterior wall - inferior transverse tibiofibular ligament

lateral wall - lateral malleolus

medial wall - medial malleolus

Question 33

What is another name for the ankle joint?

This joint is located between which bones (specific parts)?

Answer 33

The ankle joint is also known as the talocrural articulation

It is located between the distal heads of the tibia and fibula and the superior part of the talus

Question 34

How many ligaments stabilize the lateral side of the ankle joint?

Name & describe them.

Answer 34

3 separate ligaments

1) Anterior talofibular ligament - flat weak band that extends anteromedially from the lateral malleolus to the neck of the talus
2) Posterior talofibular ligament - thick, fairly strong band that runs horizontally medially and slightly posteriorly from the malleolar fossa to the lateral tubercle of the talus
3) Calcaneofibular ligament - a round cord that passes postero-inferiorly from the tip of the lateral malleolus to the lateral surface of the calcaneus

Question 35

How many ligaments stabilize the medial side of the ankle joint?

Name & describe.

Answer 35

Just one! It is called the deltoid ligament. It has 4 parts.

The deltoid ligament attaches proximally to the medial malleolus, from where it fans out, attaching distally to the talus, calcaneus, and navicular via four adjacent and continuous parts:

1) tibionavicular part
2) tibiocalcaneal part
3) anterior tibiotalar part
4) posterior tibiotalar part

Question 36

What muscles effect dorsiflexion, plantar flexion, inversion, and eversion of the ankle?

Answer 36

Dorsiflexion - anterior compartment of the leg

Plantar Flexion - posterior compartment of the leg, lateral compartment (weakly)

Inversion - tibialis anterior

Eversion - fibularis tertius (weakly), lateral compartment of the leg

Question 37

Describe the talar joint both anatomically and clinically.

What movement does it allow? (2)

What nerves provide motor ability? (2)

Answer 37

Anatomically - single synovial joint between the inferior talus and superior calcaneus

Clinically - compound joint of the subtalar joint and the talocalcaneonavicular joint, which are separated by the interosseus talocalcaneal ligament, but cannot function independently of one another

Movements - inversion and eversion of the foot

Motor - 1) plantar aspect: medial or lateral plantar nerve

2) dorsal aspect: deep fibular nerve

Question 38

Describe the transverse tarsal joint.

What movement does it allow? (2)

Answer 38

Compound joint formed by two separate joints aligned transversely, the talonavicular part of the talocalcaneonavicular joint and the calcaneocuboid joint

Movement - augment the eversion and inversion of the hindfoot by allowing extra rotation at the mid and forefoot

Question 39

What movement does the calcaneocuboid joint allow? (3)

Answer 39

Movement - inversion and eversion of the foot, circumduction

Question 40

Explain the springboard action of the lateral and medial arches of the foot.

Answer 40

The lateral and medial arches of the foot are stretched out slightly when the foot lands, which causes tension in the “ropes” of the foot, giving you the spring in your step that helps to reduce the energy needed for each step/stride (important for long distance running)

Question 41

Explain the general venous drainage of the foot.

Answer 41

Superficial veins form a plantar venous network either drain around the medial border of the foot or the lateral border:

   - medial - medial marginal vein, which become the great saphenous vein
    - lateral - lateral marginal vein, which becomes the small saphenous vein

Question 42

Explain the general lymphatic drainage of the foot.

Answer 42

Begins in subcutaneous plexi

The collecting vessels are the superficial and deep lympatic vessels, which follow the superficial veins and major vascular bundles, respectively

Medial are larger than lateral, and converge on the great saphenous vein, accompanying it to the superficial inguinal lymph nodes (around the saphenous’ termination, then to the deep inguinal lymph nodes along the proximal femoral vein

Lateral accompany the small saphenous vein to the popliteal fossa, where they enter the popliteal lymph nodes

Deep vessels follow the main blood vessels and drain into the popliteal lymph nodes, which form lymph vessels that follow the femoral vessels to the deep inguinal lymph nodes

Question 43

ALL lymph from the lower limb passes deep to the _____ ligament to ______ lymph nodes

Answer 43

Inguinal ligament

Iliac lymph nodes

Question 44

Expalin the cutaneous innervation of the foot:

Medially

Superiorly

Inferiorly

Laterally

Posteriorly

Answer 44

Medially by the saphenous nerve, extending to the head of the 1st metatarsal

Superiorly (dorsum) by the superficial (mainly) and deep fibular nerves

Inferiorly by the medial and lateral plantar nerves in a manner similar to the palm of the hand

Laterally by the sural nerve, including part of the heel

Posteriorly (heel) by medial and lateral calcaneal branches of the tibial and sural nerves

Question 45

Plantar (Babinski) Reflex:

What nerve roots does it test?

What is a normal sign?

What is an abnormal sign? What does this indicate?

Answer 45

From nerve roots L4, 5 and S1, 2

Normal = flexion of the toes

Abnormal = Babinski sign = dorsiflexion of the great toe and slight fanning of the other four toes

The abnormal sign is indicative of brain injury or cerebral disease, except in infants ages 0-4 years (then a normal toe flexion would be bad)

Question 46

What is the normal reaction for a calcaneal tendon reflex?

If the reflex is absent, what does that indicate?

Answer 46

Normal reaction is plantar flexion.

Absent, or virtually absent reflex may be caused by compressed or injured S1 nerve

Question 47

What is the most common joint injury?

Which ligament in the joint is most vulnerable?

Answer 47

Most common injury is the ankle sprain, which occurs when fibers of ligaments are torn

The lateral ligament is typically injured because it is much weaker than the medial ligament

The specific lateral ligament that is most vulnerable is the anterior talofibular ligament

Question 48

Severe ankle sprains can also result in a fracture of which part of which bone?

Answer 48

The lateral malleolus of the fibula

Question 49

_______ injuries fracture the lateral malleolus of the fibula superior to the ankle joint;

________ injuries fracture the lateral malleolus of the fibula inferior to the ankle joint.

Answer 49

Shearing injuries

Avulsion injuries

Question 50

Identify the following:

Answer 50

1. Gastrocnemius - medial head
2. Plantaris
3. Gastrocnemius - lateral head

Question 51

Identify the following:

Answer 51

1. Soleus
2. Gastrocnemius (cut & reflected)
3. Plantaris

Question 52

Identify the following:

Answer 52

1. Tibialis posterior tendon
2. Flexor digitorum longus tendon
3. Posterior tibial artery
4. Tibial nerve
5. Flexor hallucis longus muscle

Question 53

Identify the following:

Answer 53

1. Head of fibula
2. Fibular border for interosseous membrane
3. Lateral malleolus
4. Tibial border for interosseous membrane
5. Anterior border of tibia
6. Medial malleolus

Question 54

Identify the following:

Answer 54

1. Medial condyle
2. Lateral condyle
3. Intercondylar eminence

Question 55

Identify the following:

Answer 55

1. Medial tibial plateau
2. Intercondylar eminence
3. Lateral tibial plateau

Question 56

Identify the following:

Answer 56

1. Calcaneus
2. Intermediate (middle) cuneiform bone
3. Tuberosity of the calcaneous
4. Cuboid bone
5. 5th metatarsal bone
6. Proximal phalanx
7. Distal phalanx
8. Talus
9. Navicular bone
10. Lateral cuneiform bone

Question 57

Identify the following:

Answer 57

1. Sustenaculum tali
2. Talus
3. Navicular bone
4. Calcaneus
5. Metatarsal bone
6. Proximal phalanx
7. Medial cuneiform bone

Question 58

Identify the following:

Answer 58

1. Distal phalanx
2. Tuberosity of calcaneus
3. Navicular
4. Cuboid
5. Lateral cuneiform
6. Intermediate cuneiform
7. Medial cuneiform
8. Metatarsals
9. Proximal phalanx