Leg and Ankle

Question 1

what is the ankle formed by?

Answer 1

the articulation between the distal tibia and fibula with talus

Question 2

what are the two movements permitted by the ankle and what type of joint is it?

Answer 2

dorsiflexion and plantar flexion and it is a synovial joint

Question 3

why is the ankle so stable?

Answer 3

there is good congruity between malleolar mortice and trochlear and very strong ligaments

Question 4

what is the most stable position of the ankle joint and why?

Answer 4

the trochlea of talus is wider anteriorly than posteriorly and therefore during dorsiflexion the anterior part moves between the malleoli. This spreads the tibia and fibula slightly which increases their grip on the talus and so dorsiflexion is the most stable

Question 5

what forms the lateral ligament complex?

Answer 5

calcaneofibular, posterior talofibular and anterior talofibular

Question 6

what is another word for the medial ligament, and what are its origins and insertions?

Answer 6

deltoid ligament - attaches to medial malleolus and inserts onto the talus, navicular and calcaneus bones

Question 7

what is dorsiflexion and which muscles do this?

Answer 7

extension - muscles on anterior of leg

Question 8

what happens at the subtalar joint?

Answer 8

inversion and eversion

Question 9

which nerves supply the dorsiflexion muscles?

Answer 9

dorsiflexion muscles are the TA, EHL, EDL and are innervated by the deep fibular/peroneal nerve and anterior tibial artery

Question 10

what muscles are involved in plantarflexion and what are the supplied by?

Answer 10

muscles of plantar flexion are in the posterior compartment of the leg and are the TP, FHL and FDL - they are innervated by the tibial nerve and posterior tibial artery

Question 11

what is the anterior and posterior feature of the tibia?

Answer 11

anterior is tibial tuberosity and posterior is soleal line

Question 12

what is the first structure on the plantar surface of the foot?

Answer 12

calcaneum

Question 13

how many compartments are in the leg and how many muscles are in each of these compartments?

Answer 13

there are 3 - anterior (3), lateral (2) and posterior (5)

posterior splits into deep (3) and superficial (2)

Question 14

which muscles are in the anterior compartment and what are there origins and insertions?

Answer 14

anterior: TA - tibial origin and inserts medial side of big toe
EDL - origin is fibular interossesous membrane and insertion is to distal phalanx of digits 2-5
EHL - origin is also fibular interossesous membrane and goes into the distal phalanx of big toe

Question 15

what is the function of the muscles in the lateral compartment, and what are their insertions?

Answer 15

they are for eversion. FB attaches to the base of the fifth metatarsal and FL into bottom of foot.

Question 16

what muscles are in the deep portion of the posterior compartment and what are their insertions?

Answer 16

TP - comes down behind medial malleolus and inserts on the tarsal bone
FDL - inserts into distal phalanx of digits 2-5
FHL - inserts into big toe

Question 17

what muscles are in the superficial part of the posterior compartment and what are their functions?

Answer 17

Gastrocnemius - plantarflexion

soleus - plantarflexion and to squeeze blood through veins to heart

Question 18

where does the sciatic nerve travel?

Answer 18

down the posterior side and has a tibial division that innervates all muscles in the posterior compartment. The other branch is the common fibular which winds around the neck of the fibula and splits into two branches for lateral and anterior compartment.

Question 19

why do ankle ligaments heal slowly in a sprain?

Answer 19

they are relatively avascular

Question 20

why is a healed ligament usually weaker?

Answer 20

if a ligament is detached from a bone then the fibres do not grow back into bone cortex as extensively

Question 21

how does avulsion occur as a result of an ankle fracture?

Answer 21

an eversion injury will pull the strong medial ligament and therefore there is avulsion off the medial malleolus

Question 22

why is fracture dislocation of the ankle obvious?

Answer 22

there is not a lot of fat or subcutaneous tissue around the ankle so can see the malleoli

Question 23

where is osteoarthritis common?

Answer 23

large joints such as the knee

Question 24

what are functions of the foot?

Answer 24

support and transmit body weight, act as a lever to propel the body forwards during motion, act as a resilient spring to absorb shock

Question 25

where are cunieforms found?

Answer 25

medially, intermediately and laterally

Question 26

what is the function of the arch of the foot?

Answer 26

the arches of the foot help to distribute weight and act as shock absorbers and increase flexibility of the foot

Question 27

what are the three arches of the foot?

Answer 27

the medial longitudinal, transverse and lateral longitudinal

Question 28

how are the arches supported and prevented from flattening out?

Answer 28

passive support from ligaments and shapes of bones, and dynamic support from intrinsic and extrinsic muscles of the foot?

Question 29

what is pes planus?

Answer 29

it is flat feet. It is usually caused by loosened or degenerating ligaments

Question 30

what is a complication of pes planus?

Answer 30

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

Question 31

which muscles are in the toes?

Answer 31

interosseous, extrinsic and intrinsic