Imaging of the lower limb

Question 1

What is the ischial tuberosity?

Answer 1

Bony section of bum, origin of hamstrings

Question 2

What do flakes of calcification in bones indicate?

Answer 2

Tendon pathology

Question 3

Features of the pelvis

Answer 3

Sacroiliac joint
Hip joint
Iliac blade
Superior pubic ramus
Inferior pubic ramus

Question 4

What are the three compartments of the knee?

Answer 4

Medial
Lateral
Patella-femoral

Question 5

Features of the knee

Answer 5

Patella
Tibia
Medial/lateral tibial plateau 
Fibula head
Femur
Tibia and fibula

Question 6

What does corticated bone indicate?

Answer 6

Old injury

Question 7

Which bones make up the ankle joint?

Answer 7

Tibia and talus

Question 8

What is the sub-tala joint?

Answer 8

Talus articulates with calcaneus

Question 9

What is the talar-navicular joint?

Answer 9

Articulation between talus and navicular

Question 10

Where is the fore foot?

Answer 10

Metatarsals onwards

Question 11

Where is the mid foot?

Answer 11

Cuboid, navicular and cuneiform bones

Question 12

Where is the hind foot?

Answer 12

Begins immediately below ankle

Question 13

What are the two sesamoids?

Answer 13

Lateral and medial

Question 14

Features of ankle

Answer 14

Tibia
Talus
Fibular
Syndesmosis
Medial/lateral malleolus

Question 15

Bones in foot

Answer 15

Cuboid
Lateral/middle/medial cuneiform
Navicular
Talus
Calcaneus

Question 16

Main arteries in pelvis?

Answer 16

Aorta
Common iliac artery
External iliac artery
Internal iliac artery

Question 17

Which three blood vessels supply the femoral head?

Answer 17

Obturator
Lateral femoral circumflex
Medial femoral circumflex

Question 18

What is an intracapsular fracture?

Answer 18

Vessels severed, head of femur replaced unless in child where cannulated screws can reattach head

Question 19

What is an extra capsular fracture?

Answer 19

Vessels haven’t been severed so head isn’t at risk - a dynamic hip screw is used to repair

Question 20

Arteries supplying femoral head

Answer 20

Branch of the obturator artery
Lateral femoral circumflex artery
Medial femoral circumflex artery

Question 21

What is trifurcation?

Answer 21

Femoral artery gives rise to anterior tibial artery, perineal artery and posterior tibial artery

Question 22

Which scan is used to visualise arterial system?

Answer 22

CT angiogram

Question 23

What are the two venous systems in the lower limb?

Answer 23

Superficial and deep

Question 24

What does DVT stand for?

Answer 24

Deep Vein Thrombosis

Question 25

Why is proximal DVT dangerous?

Answer 25

Danger of travelling up the body and patient

Question 26

What is a doppler ultrasound and how does it work?

Answer 26

Employs the 'doppler' effect to determine whether blood flow is toward or away the probe and its relative velocity. It is calculated by the shift in frequency of a particular sample. When the doppler shift falls in the audible range, the machine uses stereo speakers to produce pulsating sound

Question 27

What does it indicate when it is red on a doppler ultrasound?

Answer 27

Coming towards probe

Question 28

What does it indicate when it is blue on a doppler ultrasound?

Answer 28

Moving away from probe

Question 29

What is a patent blood vessel?

Answer 29

Open and blood is flowing through

Question 30

What does haziness on an x-ray indicate?

Answer 30

Stress fracture

Question 31

Why is a stress fracture difficult to see on an x-ray?

Answer 31

Initially there will be no visible fracture but it develops and becomes visible on an x-ray over time as the wound heals

Question 32

What is an insufficiency fracture?

Answer 32

Normal load, stress fractures associated with vitamin D deficiency and osteoporosis

Question 33

What is a Lover's fracture?

Answer 33

Calcaneal fracture

Question 34

What is a lipohaemarthrosis?

Answer 34

Fracture of tibial plateau, bone fracture shows fat in joint

Question 35

When should a fracture/vascular assessment be performed?

Answer 35

Before orthopaedic fixation

Question 36

What is diabetic osteomyelitis?

Answer 36

Bone is 'eaten' by infection