ORTHO 218 Hip Fracture

Question 1

What is a fracture?

Answer 1

A loss of continuity of the substance of a bone due to physical force

Question 2

What is a dislocation?

Answer 2

Complete loss of contact between articulating surfaces of a joint

Question 3

What types of fractures can you get in Long bones?

Answer 3

Transverse, spiral, oblique, comminuted, segmental

Question 4

What fractures do you get in cancellous bones?

Answer 4

Impacted/crush or compression

Question 5

What type of fractures due you get peri-articularly?

Answer 5

Avulsion fractures

Question 6

What are the two types of hip fracture (broadly speaking)

Answer 6

Intracapsular and Extra capsular

Question 7

Describe an intracapsular hip fracture?

Answer 7

Proximal to the intertrochanteric line

Usually presents with external rotation, adduction and shortening

Question 8

What is avascular necrosis and what type of hip fracture is it more likely in?

Answer 8

Disruption of blood supply to the femoral head more likely in an intracapsular fracture

Question 9

What is the blood supply to the femoral head?

Answer 9

Medial and lateral femoral circumflex arteries

Question 10

What is an extracapsular fracture?

Answer 10

Distal to the intertrochanteric line

Question 11

What are the three R’s for treating a fracture?

Answer 11

Reduction - open/close and how accurate?
Retention - stabilise surgically or not
Rehab - Get them weight bearing asap

Question 12

What type of fracture needs to be reduced very accurately - therefore surgically?

Answer 12

Fracture through a joint

Question 13

What are the options for treating an extracapsular fracture?

Answer 13

Dynamic hip screw - providing optimal stability whilst still allowing micromovement
Cannulated screw can be added if additional stability is required

Question 14

What are the main treatments for an intracapsular fracture?

Answer 14

Hemiarthroplasty or THR

Question 15

What are some of the complications of fractures?

Answer 15

Fat embolism, nerve, vessel or visceral damage, union problems, joint stiffness or myositis ossificans

Question 16

What is the 1st stage of fracture healing?

Answer 16

Formation of the fracture haematoma containing required cells for required regeneration - fibrin clot, polymorphs, platelets and monocytes. Later - fibroblasts, osteoprojenitor cells and vascular in growth

Question 17

What is the 2nd stage of fracture healing?

Answer 17

Soft callous
Bony fragments become united by fibrous/cartilagenous tissue, usually when swelling and pain subside
Still possible to angulate however

Question 18

What is the 3rd stage of fracture healing?

Answer 18

Hard callous - as the cartilage/fibrous tissue becomes mineralised and converted into endochondral and membranous bone by osteoblasts
= increased stiffness and external callous formation

Question 19

What is the 4th Stage of fracture healing?

Answer 19

Remodelling - where woven bone becomes lamellar bone and excess callous is removed and the medullary canal reconstituted

Question 20

What is osteoporosis?

Answer 20

Disease characteristics by low bone mass and micro architectural deterioration of bone tissue and an increased fracture risk

Question 21

How do you diagnose osteoporosis?

Answer 21

DEXA scan

Tscore >2.5 Standard deviations from the gender matched young adult mean

Question 22

How do you diagnose osteopenia?

Answer 22

T score between 1-2.5 Standard deviations

Question 23

What is the Z score?

Answer 23

Bone density and number of standard deviations away from the gender and age matched mean - used more in children

Question 24

What are some risk factors for the osteoarthritis?

Answer 24

Hypogonadism in men
Smoking
Alcohol
Low BMI
Inactivity
Caucasian
Medication: aromatase inhibitors and GnRH agonists

Question 25

What are the treatments for osteoporosis?

Answer 25

Lifestyle : exercise and falls prevention
AdCalD3
Drugs:
to increase bone formation and decrease bone resorption

Question 26

What drug treatment increases bone formation?

Answer 26

Teriparatide - recombinant human PTH given in pulses (paradoxically increases BMD!)

Question 27

What drug treatments decrease bone resorption?

Answer 27

Bisphosphanates - alendronic acid inhibits osteoclasts

RANK ligand inhibitor - denosuman prevents osteoclast differentiation, activation and survival

Question 28

What is osteomalacia(OM) and ricketts?

Answer 28

Inadequate mineralization of the osteoid due to vitamin D deficiency

Question 29

What are some causes of OM and ricketts?

Answer 29

Lack of sunlight and diet deficiency/malabsorption
Medication : rifampicin and phenytoin
Liver or renal disease
Low phosphate

Question 30

How do children with ricketts look?

Answer 30

Protruding forehead/large head
Kyphosis and pigeon chest
Protruding abdomen
Curved tibia and fibula

Question 31

What are the clinical features of OM?

Answer 31

Bone pain
Proximal muscle weakness
Back pain
Stress fractures

Question 32

What is pagets disease?

Answer 32

Disorder of bone metabolism

Question 33

What is the pathophysiology behind pagets disease?

Answer 33

There is initial overactivity - excessive resorption followed by increased osteoblast activity and bone formation however new bone is woven bone (disordered not lamellar)

Question 34

Where does pagets disease common affect?

Answer 34

Spine, pelvis, skull and femur

Question 35

What can some symptoms be of pagets disease?

Answer 35

Often asymptomatic
Bone pain - worse on weight bearing
Pathological
High cardiac output
Compression effects - CN palsies, sciatica and cauda equina

Question 36

How do you diagnose pagets disease?

Answer 36

Xray, increased ALP and isotope scan

Question 37

How do you treat pagets disease?

Answer 37

Bisphosphonates - stimulate production of lamellar bone