Geneal Principle of fracture

GENERAL

PRINCIPLE

OF

FRACTURE

Fracture :is an interruption of bone continuity.

Dislocation : disruption of the continuity of a joint .

Fracture dislocation : dislocation together with a

fracture of one or more of the bones forming the joint.

Mechanism of injury

1- Direct trauma

A direct trauma usually causes a fracture

at the

site of impact . The fracture is most often

transverse or comminuted and the

associated soft tissue damage is more

because of its crushing effect .

2- Indirect trauma

An indirect trauma causes fracture at a

site which is situated at a distance from

where the force is applied . Such a force

usually causes an oblique , spiral or

transverse fracture . The associated soft

tissue damage is less . This indirect force

is transmitted along the bone or the limb .

3- Repeated trauma

A fracture caused by repeated minor

trauma over a period of time is called

fatigue fracture.

Certain weight bearing bones fracture

because

of repeated stress and strain applied to

them ,

like during walking .

TYPES OF FRACTURE

According to etiology:

1 - Traumatic fracture : this is a

fracture due to sustained trauma.

E.g. fractures caused by a fall , road

traffic accident , fight etc…

2-PATHOLOGICAL fracture

A- Aminor trauma to already weakened bone by

pre-existing disease , by a degree of stress or

trauma .

B-the disease maybe generalized e.g.

osteoporosis,

or localized e.g. osteomyelitis , bone tumors.

fatigue fracture ))3-Stress fracture

- fracture that occur when a bone is repeatedly

exposed to unaccustomed stresses , it may

crack under their summated effects .

- Usually in young adult .

SITES: stress fracture commonly involves

the metatarsal , the fibula

and the tibia .

According to soft tissue involvement :

are those in which the 1-closed

(simple)fracture :

overlying skin is intact .

2-open (compound) fracture : involve wounds

that

communicate with the fracture , or where

fracture hematoma is exposed , and may thus

expose bone

to contamination . Open injuries carry a higher

risk of infection .

.- clean fracturecontaminated

fracture.-

3- complicated fracture : there is associated

damage

.to nerve , blood vessels or internal structure

According to shape of fracture line

:

1- Transverse ( angle < 30 )

2- oblique ( angle > 30 )

3- spiral

4- comminuted

5- segmental

According to extent

1- complete

fracture

2- incomplete fracture

:

- Fissure fracture : incomplete fracture in adult

bone.

- Greenstick fracture : incomplete fracture in

child

(soft bones & thick periosteum

)

According to impaction

1- Non-

impacted

2- impacted

:

- A fragment is driven into the other

fragment .

- Mainly occurs in epiphyseal

areas.

Fracture displacement

Displacement of fracture is defined in terms of

the abnormal position of the distal fracture

fragment in relation to the proximal bone .

Types of displacement

1- Overlap

2-Side displacement

3- Angulation

4- Rotation

DIAGNOSIS OF FRACTURE

The diagnosis of a fracture is both

clinical and radiographic

.

Clinical diagnosis :

The patient presents because of pain and

inability to use the injured part,(loss of

function) .

History : description of the accident is known

from the patient or the attendants .

General examination : for shock , head ,

visceral

and other skeletal injuries .

Local examination : the signs of a fracture are :

1. Tenderness : localized tenderness over a

bone after an injury is sufficient for making the

provisional diagnosis of a fracture until x-ray

is taken .

Tenderness may be a sign of a fissure fracture

.

2. swelling : the swelling is evident in one

hour, maximum in one day , then

gradually disappears after few days .

3.Deformity : deformity is present when the

fracture is

displaced ; not marked when one bone only of

the

forearm or the leg is fractured ; and is absent in

a fissure fracture .

4. Abnormal mobility : abnormal mobility can be

elicited

when the fracture is complete .

5.Crepitus : crepitus is the friction sound between

the

fractured surfaces . The examiner need not elicit

this

sign because it is painful, can be harmful, and

isn’t

essential for reaching the diagnosis of a fracture

RADIOGRAPHIC EXAMINATION

The x-ray shows the particulars of the fracture,

and

is also a documentary record of the injury :

1. The injured part must be examined in at

least two

views, anteroposterior and lateral views . More

views

are often required in special cases ,e.g. carpal

scaphoid.

2. The x-ray must include the joint adjacent to

the fracture . In case of forearm , both the

elbow and wrist joints are to be included .