Lower Leg Anatomy

Question 1

What compartments are leg muscles split into?

Answer 1

• Lateral
• Anterior
• Posterior

Question 2

What nerves supplie the leg muscles?

Answer 2

Common fibular nerve:

• > Sup. Fibular nerve supplies lateral comp.
• > Deep Fibular nerve supplies Ant. Comp.

Sciatic Nerve -> Tibial Nerve -> Post. Comp.

Question 3

What type of joint is the ankle and what bones articulate?

Answer 3

Synovial Hinge 
Malleolar mortise (fibula & tibia form this bony arch) with trochlea of talus

Question 4

When is the malleolar grip strongest in the ankle?

Answer 4

During Dorsiflexion

Question 5

When is the ankle joint most unstable?

Answer 5

During Plantarflexion

Question 6

Describe the ligaments making up the ankle joint capsule?

Answer 6

Thin on front and back

Strong on the sides thanks to Medial & LAteral Collateral Ligament

Question 7

Describe the parts of the ankle medial collateral ligament? (Aka deltoid ligament)

Answer 7

3 slips arise from the medial malleolus (tibia) to:

• Talus
• Calcaneus
• Navicular

Together they form a large, triangular strong ligament

Question 8

Function of the medial collateral ligament of the ankle?

Answer 8

Stabilises the joint during eversion

Question 9

Describe the parts and clinical relevance of the lateral collateral ligament of the ankle?

Answer 9

3 slips:

• Anterior Talofibular
• Posterior Talofibular
• Calcaneofibular

Its weaker than the medial so its the most commonly injured

Question 10

What muscles are responsible for Dorsiflexion of the ankle?

Answer 10

• Tibialis Anterior
• Extensor Digitorum Longus
• Extensor Hallucis Longus
• Peroneus

Question 11

What muscles undertake plantar flexion of the ankle?

Answer 11

Gastrocnemius
Soleus
Plantaris
Tibialis Post.
Flexor Hallucis Longus
Flexor Digitorum Longus

Question 12

What movement causes ankle sprains?

Answer 12

Inversion

Question 13

What is a pott Fracture?

Answer 13

Refers to bimalleolar fractures

Question 14

What is Footballer’s Ankle?

Answer 14

Repetitive strain injury to the ant capsule of the ankle

Question 15

What is Tarsal Tunnel Syndrome

Answer 15

Tibial nerve compression deep to the flexor retinacula

Question 16

What are the layers of the foot from plantar->in?

Answer 16

Layer 1 - Plantar Aponeurosis
Layer 2 - Lateral plantar nerve/artery
Layer 3 - Medial plantar nerve/artery
Layer 4 - Plantar then dorsal interossei

Question 17

Major bones of the foot?

Answer 17

Talus - ankle joint
Calcaneus/Os Calcis - Heel bone
Tarsal bones
Metatarsals
Phalanges

Question 18

AT what joints does the ankle move?

Answer 18

Ankle Joint – Dorsiflexion/plantarflexion

Subtalar joint & Transverse tarsal joint – Inversion & Eversion

Question 19

What muscles handle inversion/eversion?

Answer 19

Inversion - Tibialis post & Ant

Eversions - Fibularis Longus & brevis

Question 20

Purpose of the arch of the foot?

Answer 20

Shock absorption by deforming on contact
Distribute weight over foot
Springboard during running/walking/jumping

Question 21

Parts of the arch of the foot?

Answer 21

1 longitudinal arch made of 3 parts:

• Medial (most important)
• Lateral
• Transverse

Question 22

How is the integrity of the foot arch maintained?

Answer 22

• Shape of united bones
• Plantar aponeurosis
• Long/short plantar ligaments
• Spring Ligament (Calcaneonavicular)
• Intrinsic foot muscles

Question 23

List some conditions related to foot arches?

Answer 23

• High arched foot can be congenital
• Acquired flat feet due to TIbialis post dysfunction
• Flat Feet is also common in old people and kids

Question 24

What muscles form the Achilles Tendon?

Answer 24

Gastrocnemius & Soleus (plantar flexers)

Question 25

How does ankle arthritis arise?

Answer 25

Mostly Post-traumatic

If theres no trauma history and they’re young (<50) it may be haemochromatosis

Question 26

How do we treat ankle arthritis?

Answer 26

Ankle replacement

Question 27

What is a cavovarus foot?

Answer 27

Cavo = high arch
Varus = medially slanted hindfoot
Calves may also be atrophic

Question 28

What causes a cavovarus foot?

Answer 28

Congenital
Neuro disorders
Post-traumatic

Leads to muscles weakness:

• Intrinsic muscles - clawed toes
• Peroneus Brevis - Hindfoot varus
• Tibialis anterior - Equinus (can’t dorsiflex properly) and adducted forefoot.

Question 29

How do we spot a varus?

Answer 29

Look from the front, if you can see the heel medially its called the “peekaboo” sign

Question 30

How would a cavovarus foot present to us?

Answer 30

• Plantar calluses and shoe problems
• Ankle instability
• Altered Gait
• Stress fracture to lateral metatarsals

Question 31

How do we test for a cavovarus foot?

Answer 31

Diagnosed clinically but coleman block test differentiates hindfoot varus or forefoot driven hindfoot varus