Imaging Flashcards
One view on imaging is enough for diagnosis - true or false
False
Some fractures may not be visible from certain angles
Need at least 2
How many views do you need in X-rays of the cervical spine
3
How many views do you need in X-rays of the scaphoid
4
How might a fracture appear on X-ray
Lucency crossing bone
Cortical extension - incomplete border
What do fractures involving the joint increase your risk of
Malalignment
This goes on to cause faster wear and tear - leads to secondary OA
What causes impacted fractures
Axial loading force
What is an avulsion fracture
When tendon/ligament is torn off the bone and pulls off a small fragment
List common avulsion fracture mimics
sesamoid bones
accessory ossification centres
Old fractures
What is the posterior fat pad sign
May appear behind elbow on X-ray
Always abnormal and indicates elbow trauma
Why do children get unique bone injuries
Bones are still soft so may bend and bow rather than snapping
What is a buckle fracture
Seen in kids
Appears as a bulge in the bone as it is where bone has gone into itself
What is the weakest part of developing bone
Growth plate - physis
Prone to injury and growth deformity
What is a Salter-Harris fracture
epithesis slips off the metaphysis due to fracture in growth plate
When should you suspect non-accidental injury
When injury doesn’t match the story
Leg fractures in babies who can’t walk
Why must you be careful with fractures in bony rings
Very unlikely that they will break in just one place so must look for further injury
Give examples of bony rings within the body
Spinal canal
Pelvis
Forearm
Lower leg
Which foreign bodies will be seen on X-ray
Metal
Glass
Which foreign bodies cannot be seen on X-ray
Plastic
Wood
What is a pathological fracture
When abnormality seems out of proportion to the mechanism of injury
What can cause pathological fractures
malignancy, osteoporosis or other metabolic bone diseases
What is the risk with supracondylar fractures
Damage to the brachial artery and surrounding nerves
What is the risk with scaphoid fractures
Blood supply can be disrupts making it prone to non-union or AVN
What is a Bennett’s fracture
Involves articular surface of 1st metacarpal base
Tendons pull on thumb leading to displacement
Lower limb fractures are associated with high morbidity and mortality - true or false
True
List common limitations of X-rays
Assessment difficult due to overlapping anatomical structures
Some fractures are impossible to view as projections don’t show them up or they are undisplaced
Don’t show soft tissue injury
Which imaging techniques would you use to view soft tissue injuries
US = superficial
MRI = deep
List typical sites of impacted fractures
Femoral neck
Tibial plateau
Calcaneus
What causes a pelvic ring fracture
High energy trauma - RTA or fall from height
Osteoporosis - low energy trauma
What are the risks of intracapsular femoral fractures
Interferes with blood supply to femoral head
Prone to AVN or non-union
What are the 2 types of proximal femoral fractures
Intracapsular
Extracapsular
How do you treat extracapsular femoral fractures
Internal fixation using DHS
How do you treat intracapsular femoral fractures
Arthroplasty
What are the risks of femoral shaft fractures
Blood loss
Fat embolus
What usually accompanies significant soft tissue injury to the knee
An effusion in the suprapatellar space
What surrounding structure can be damaged by knee dislocations
Ligaments
Blood vessels - popliteal artery
What causes tibial plateau fractures
Valgus force - e.g. being hit on the outside of the knee
Which injury mechanism is most common in ankle injury
Inversion
Eversion
Ankle fractures usually occur in multiples - true or false
True
What predisposes you to tendon rupture
Diabetes
RA
Steroid use
