Leg & Ankle

Question 1

What bones are involved in forming the ankle joint?

Answer 1

it is formed by the articulation between:

1. distal tibia
2. distal fibula
3. talus

Question 2

What are the only 2 movements present at the ankle joint?

Answer 2

it is a synovial hinge joint that permits:

1. dorsiflexion (extension)
2. plantarflexion

Question 3

What factors help to contribute to the stability of the ankle joint?

Answer 3

1. there is good congruity between the malleolar mortice and trochlea of the talus

the malleoli grip the talus and keep it in place

2. very strong ligaments

Question 4

Label the components of the ankle joint

Answer 4

Question 5

Why is dorsiflexion the most stable position of the ankle joint?

Answer 5

1. the trochlea of the talus is wider anteriorly than posteriorly
2. during dorsiflexion, the anterior part of the trochlea moves between the malleoli
3. this spreads the tibia and fibula slightly and increases their grip on the talus

Question 6

What are the 2 ligament complexes that stabilise the ankle joint?

Answer 6

lateral ligament complex

medial ligament complex (or deltoid)

Question 7

What are the 3 ligaments of the lateral ligament complex?

Answer 7

1. anterior talofibular ligament
2. posterior talofibular ligament
3. calcaneofibular ligament

Question 8

label the lateral ligaments of the ankle joint

Answer 8

Question 9

What are the attachments involved with the medial ligament?

Answer 9

it is attached to the medial malleolus and fans out to attach to the talus, navicular and calcaneus

Question 10

What movements of the ankle joint are shown?

Answer 10

Question 11

What movements are shown?

Answer 11

Question 12

Which joint is responsible for eversion and inversion?

Answer 12

subtalar joint

this is the between the talus and the calcaneus (heel bone)

Question 13

Which muscles are involved in dorsiflexion?

Answer 13

anterior compartment of the leg

tibialis anterior (TA)

extensor hallucis longus (EHL)

extensor digitorum longus (EDL)

Question 14

What is the artery and the nerve of the anterior compartment of the leg?

Answer 14

deep fibular (peroneal) nerve

anterior tibial artery

Question 15

What are the muscles involved in plantarflexion?

Answer 15

posterior compartment of the leg

1. tibialis posterior
2. flexor hallucis longus
3. flexor digitorum longus

Question 16

What is the artery and the nerve of the posterior compartment of the thigh?

Answer 16

tibial nerve

posterior tibial artery

Question 17

What are the 3 muscles of the anterior compartment of the thigh?

What is their function?

Answer 17

1. tibialis anterior (TA)
2. extensor digitorum longus (EDL)
3. extensor hallucis longus (EHL)

they are involved in dorsiflexion of the ankle and extension of the toes

Question 18

What is the insertion of the tibialis anterior?

Answer 18

it originates from the lateral surface of the tibia and interosseous membrane

it inserts on the base of the first metatarsal bone

Question 19

What is the origin and insertion of extensor hallucis longus?

What is significant about the insertion of its tendons?

Answer 19

it arises from the middle portion of the fibula and the interosseous membrane

its tendon inserts on the distal phalanx of the big toe

this allows it to extend the big toe

Question 20

What is the origin and insertion of extensor digitorum longus?

What is significant about the insertion of its tendons?

Answer 20

it originates from the lateral condyle of the tibia and interosseous membrane

its tendons insert onto the middle and distal phalanges of digits 2-5

this allows it to extend the toes

Question 21

label the anterior leg muscles

Answer 21

Question 22

How are the posterior leg muscles divided?

Answer 22

there are 3 deep compartment muscles and 2 superficial compartment muscles

Question 23

What are the 3 muscles of the deep group of the posterior compartment?

Answer 23

1. tibialis posterior (TP)
2. flexor hallucis longus (FHL)
3. flexor digitorum longus (FDL)

they are involved in plantarflexion and flexion of the toes

Question 24

what is the origin and insertion of tibialis posterior?

Answer 24

it originates from the tibula and fibula

it inserts onto the navicular and medial cuneiform bone

it can cannot flex the toes

Question 25

What is the origin and insertion of flexor digitorum longus? What does the insertion of its tendons allow it do?

Answer 25

it originates from the posterior surface of the tibia it inserts onto the plantar surface of the base of the distal phalanges of digits 2-5 this allows it to flex the toes

Question 26

What is the origin and insertion of flexor hallucis longus? What does the insertion of its tendon allow it to do?

Answer 26

it originates from the fibula it inserts onto the plantar surface of the distal phalanx of the big toe (hallux) this allows it to flex the big toe

Question 27

Why does flexor hallucis longus play such a crucial role?

Answer 27

plantar flexion is crucial to walking as the final stage in walking is pushing off of the ground with the big toe (toe-off) (going on tip toes is also plantar flexion when the foot is fixed on the ground)

Question 28

label the deep muscles of the posterior leg

Answer 28

Question 29

What are the 2 superficial muscles of the posterior leg?

Answer 29

gastroenemius is the most superficial muscle soleus is attached to the soleal line and covers all of the deep muscles

Question 30

What are the functions of the superficial muscles of the posterior leg?

Answer 30

they are plantarflexors of the ankle soleus contracts to squeeze the underlying deep veins of the leg to force the blood back to the heart

Question 31

What is the Achilles tendon? Where does it insert?

Answer 31

both soleus and gastroenemius insert onto the calcaneum via the Achilles tendon

Question 33

Label the superficial muscles of the posterior leg

Answer 33

Question 34

What are the 2 muscles of the lateral compartment of the leg? What is their function?

Answer 34

**fibularis longus** and **fibularis brevis** they are involved in eversion

Question 35

What are the 2 divisions of the sciatic nerve? Which compartments of the leg are innervated by which divisions?

Answer 35

**tibial division:** * this innervates all the muscles in the posterior compartment **common fibular division:** * this divides into the superficial fibular nerve that innervates the lateral compartment * and the deep fibular nerve that innervates the anterior compartment

Question 36

What action are most ankle injuries caused by?

Answer 36

most ankle sprains are inversion injuries with twisting of a plantar-flexed foot this causes tearing and stretching of the lateral ligaments

Question 37

Why do ligaments heal slowly?

Answer 37

they are relatively avascular

Question 38

what happens if a ligament is detached from bone?

Answer 38

fibres do not grow back into the bone cortex as extensively this means that the healed ligament is usually weaker

Question 39

How do torn ligaments affect the ankle joint? What ligaments of the ankle joint are weaker?

Answer 39

they predispose to dislocation the lateral ligament is weaker than the medial ligament, particularly the anterior talofibular part

Question 40

What injury is shown? What usually causes this?

Answer 40

**ankle fracture** this is caused by fracture of the lateral malleolus it may be coupled with fracture of the medial malleolus

Question 41

What causes an eversion injury? What injuries are associated with this?

Answer 41

they are caused by the foot being forced into an eversion position this pulls the medial ligament and causes avulsion of the medial malleolus this causes the talus to rotate laterally and fractures the fibula

Question 42

What injury is shown here?

Answer 42

fracture dislocation this tends to be obvious as there is not much fat or subcutaneous tissue around the ankle

Question 43

what injury is shown here?

Answer 43

osteoarthritis of the ankle joint

Question 44

What are the tarsal bones?

Answer 44

Question 45

Why is the foot a series of small bones and ligaments?

Answer 45

this allows the foot to deform to absorb shock and adapt to walking on uneven surfaces if the foot was rigid, each impact with the ground would generate large forces

Question 46

What are the roles of the tarsal bones?

Answer 46

1. to support and transmit body weight 2. acts as a lever to propel body forward during motion 3. acts as a resilient spring to absorb shock

Question 47

What are the roles of the arches of the feet?

Answer 47

**_STABILITY_** they help to distribute weight, act as shock absorbers and increase the flexibility of the foot they also act as springboards for propulsion during walking, running and jumping

Question 48

What are the 3 arches of the foot?

Answer 48

1. medial longitudinal 2. lateral longitudinal 3. transverse

Question 49

What are the methods of passive and dynamic support of the foot arches?

Answer 49

**passive support:** ligaments and the shape of the bones **dynamic support:** intrinsic and extrinsic muscles of the foot

Question 50

What would happen if the arches of the foot were not supported?

Answer 50

they would flatten out due to the weight of the body when standing

Question 51

What condition is shown?

Answer 51

**pes planus** this is seen in adolescents or adults it is usually caused by loose of degenerating ligaments

Question 53

What are the 2 types of pes planus?

Answer 53

flexible and rigid flexible is more common - this is where the arch is present when not bearing weight but absent when standing

Question 54

What are the exacerbating factors in pes planus?

Answer 54

gaining weight and/or spending a long time standing

Question 55

Why must pes planus be treated even if it is asymptomatic?

Answer 55

it can result in displacement of the talus infero-medially this causes misalignment of the ankle and knee causing pain in these areas this can also decrease shock absorption by the foot leading to lower back pain

Question 56

What is the treatment for pes planus?

Answer 56

orthotics (specialised insoles) that support the arches of the foot

Question 57

What movements are present at the toes? Which joints are involved?

Answer 57

**flexion and extension:** acheived by the metatarsophalangeal joints, PIPJs, DIPJs **abduction and adduction:** limited abduction and adduction occurs at the metatarsophalangeal joints