W2: Trauma and Fractures

Question 1

What is a fracture?

Answer 1

A break in the continuity of the cortex of the bone.
Is the same as a break.

Question 2

What are the different types of fracture by cause?

Answer 2

Traumatic
Pathological
Atypical
Physeal
Iatrogenic
Peri-prosthetic.

Question 3

What is a traumatic fracture?

Answer 3

Occurs when significant or extreme force is applied to a bone e,g fall or car acccident
Can be from different forces such as extension or twisting

Question 4

What is a pathological fracture?

Answer 4

Occurs in areas of weakned bone attricuted to another disease such as metabolic abnormalities, cancer of benign lesions

Question 5

What is meant by an atypical fracture?

Answer 5

An uncommon complication of long term use of bisphosphonates - inhibit bone resorption short term - long tem can inhibit bone mineralisation and decrease bone turnouver.

Question 6

What is a physeal fracture?

Answer 6

Disruptions in the cartilagenous physis or growth plate of the bone
Problematic as can impair further growth of the bone in children

Question 7

What is a peri-prostethic fracture?

Answer 7

Fractures that occur in association with an orthopaedic implant

Question 8

What is an iatrogenic fracture?

Answer 8

Complication of a medical intervention such as during orthopaedic surgery.

Question 9

What is meant by internal fixation of a fracture?

Answer 9

Method of physically reconnecting the bones
Often uses special nails, plates, wires etc to place inside bone to hold in the correct place.
Fixation is below the skin and into the bone

Question 10

What is external fixation of a fracture?

Answer 10

Pins and wires are inserted into the bone percutaneously and held in place by an external scaffold.
This holds the bone in the correct place for healing or to prevent further injury.

Question 11

What is meant by open/closed reduction of a fracture?

Answer 11

Reduction = realignment of a fracture
Open - surgically when an incision is made
Closed - no surgery, man handling to mainpulate bone back in - often done in A+E department.

Question 12

What is intra medullary nailing of a fracture?

Answer 12

Metal rods are inserted into the centre of bone in th emedullar cavity (where bone marrow is found) and fixed at both ends with screws.
Provides a solid support for fractured bones, act as a scaffold for healing.

Question 13

What type of fracutes need intervention in order to heal?

Answer 13

The majority of fractures heal themselves.
Intervention is normally only required in comminuted, high energy or open fractures or in elderly patients.
Or in risk of bone fracture causing damage to nearby neuro vasculature.
Internal fixation is not used as a first resort over leaving it alone as the complication of poor fixation are worse than leaving the bone to heal by itself.

Question 14

What are the different methods of actively managing a fracture?

Answer 14

Pain relief
Stabilise the broken bain - fixation, reduction
Allow bone to heal in correct anatomical position
Rehabilitate the joint back to full function - physiotherapy

Question 15

What are the different elements of bone anatomy that are important in fracture healing?

Answer 15

Bone length
Bone alignment
Bone rotation

Question 16

What is a torsion fracture?

Answer 16

Also known as a spiral fracture - when a rotational/twisting force is applied to bone
Fracture in a corkscrew like fashion.
Low energy fracture

Question 17

What type of fracture is caused by a bending force?

Answer 17

Oblique or transverse

Question 18

What type of fracture results from a tensile (stretching force)?

Answer 18

An avulsion fracture
Or a transverse fracture.

Question 19

What type of fracture develops from a crush force?

Answer 19

Compression

Question 20

What are the different classifications of fracture regarding the position around the jont capsule?
Why is this important in femoral neck fractures?

Answer 20

Intra-capsular
Extra-capsular
Intracapsular may cause damage to capsular retinacular arteries (and nutrient artery not always and less important) - loss of blood supply o femoral neck as ligamentum terest supply is insufficient cause avascular necorosis
However in an extracapular fracture capsular arteries remain intact so blood supply to femoral head remains.

Question 21

What is mean by ambulatory independence?

Answer 21

Individual able to walk 50m without assistance.

Question 22

What local events may occur secondary to a fracture?

Answer 22

Soft tissue injury
Damage of blood supply
Soft tissue interposition at fracture site - soft tissue get imbetween bone fractures.
Bone death at fracture ends

Question 23

What prerequisites are needed for bone healing?

Answer 23

Adequate blood supply
Adequate mechanical stability

Question 24

What are the different antomical segments of the bone?

Answer 24

Epiphysis
(growth plate)
Metaphysis
Diaphysis

Question 25

What is the blood supply to a typical long bone?

Answer 25

Nutrient artery - intramedullar and supplies the inner 2/3 of cortex has an ascending and descencing branch

Metaphyseal vessels - rich supply from soft tissue to spongy bone.

Periosteal vessels - supplies outer 1/3 of cortex

Question 26

What are the two different mechanisms of bone healing and how are they different?

Answer 26

Direct/primary bone healing - no motion at fracture site, no callus formation
Indirect/secondary bone healing - motoin at fracture site, callus formation

Question 27

What is the mechanism of direct bone healing?

Answer 27

Appositional healing - no gap so cutting cones can cross the fracture site, osteoclasts create longitudinal cavities which are then filled by osteoblasts, endothelial cells. mature by direct remodelling to the lamellar bone.
Gap healing - vessels and mesenchymal cells must transverse across gap form woven bone which is perpendicular to bone axis forms a small soft callus.
Edges of fracture become necrotis and undergo e reabsorption.
Undergoes a secondary reconstruction where cutting cones become involved to remodel into mature bone and can brdige the gap, haversion remodelling occurs.

Question 28

What are the features of indirect bone healing?

Answer 28

Motion at the fracture site
Callus formation
Bridging periosteal soft callus
Medullary hard callus re-established structural continuity
Endochondral ossification
Rapid process. (but slower than direct bone healing)

Question 29

What are the key parts of inflammation in indirect bone healing?

Answer 29

Haematoma
Necrotic material
Phagocytosis of debirs

Question 30

What are the key parts of reapir in indirect bone healing?

Answer 30

Granulation tissue formation
Acid environment (hypoxia leads to build up of lactic acid)
Periosteum - source of osteoprogenitor cells
Cortical osteoclasis if required - surgical break and reshape of bone if healing incorrectly or just bone reabsorption naturally

Question 31

What are the key processes in late repair in indirect bone healing?

Answer 31

Fibrous tissue is replaced by cartilage
Endochondral ossification occurs
Periosteal healing my membranous ossification

Question 32

What are the key stages in regenerationand remodelling of bone in indirect bone healing?

Answer 32

Replacement of callus/woven bone with lamellar bone
Continued osteoclasis (not surgical - just physiological absorption of bone)
Mechanical strain on bone

Question 33

What is wound debridement and when might is be required?

Answer 33

Debridement - removal of all dead or infection tissue from a wound, thoroughly cleaning the wound to help it heal better.
In gross contamination (agricultural, marine or sewage wound)
In compartmen syndrome
In avascular limb
Multi injured patient

Question 34

What is the timing associated with debridement?

Answer 34

occurs within first 24 hours in presence of senior orthopaedic and plastic surgeon
6 hour rule does not apply

Question 35

What is the 6 hour rule of fractures?

Answer 35

Open fractures require surgical intervention within 6 hours in order to prevent/reduce the risk of inflammation of the bone and bone marrow from infection.

Question 36

What is the blood supply to the femoral head?

Answer 36

Obturator artery has a ligamentum teres branch that splits into epiphyseal arteries.
Profunda femoris branches into the lateral femoral circumflex (ant) and the medial femoral circumflex (post).
The transverse branch of the lateral femoral circumflex loops round to connect to medial. Has an ascending branch that gives off anscending cervical branches to supply intracapasukar region, are United superiorly by the subsynovial artery
All of the following help supply the head and neck of the femur.