Pelvis and Acetabulum Flashcards
Why do pelvic fractures occur in young individuals?
High energy injuries
What type of pelvic fractures occur in older people with osteoporosis?
Low energy pubic rami fractures
What forms the pelvic ring?
Ilium, ischium, pubic bone, sacrum and supporting ligaments
If the pelvic ring is disrupted in one area, what does this guarantee?
There will be further disruption elsewhere in the ring
What arteries and veins are at risk in pelvic fractures?
Internal iliac arteries and pre-sacral venous plexus
Nerve roots and branches of where are at risk in pelvic fractures?
Lumbo sacral plexus
Describe a lateral compression fracture of the pelvis?
Usually occurs with a side impact (e.g. RTA) where one half of the pelvis is displaced medially
Fractures through the pubic rami or ischium are accompanied by what?
Sacral compression fracture or SI joint disruption
Describe a vertebral shear fracture of the pelvis?
Occurs due to axial force on one hemipelvis (e.g. fall from height, rapid deceleration) where the affected hemipelvis is displaced superiorly
Which leg will look shorter in a vertebral shear fracture of the pelvis?
Affected leg
What happens in an anteroposterior compression injury of the pelvis?
Wide disruption of the pubic symphysis (open book fracture)
Which type of pelvic fracture has the greatest risk of bleeding?
Anteroposterior compression injury (open book fracture)
As pelvic volume increases following a fracture, what else increases?
Degree of displacement
How do you treat an open book pelvic fracture?
Promptly reduced to minimise the pelvic volume and allow tamponade of bleeding
If you take initial measures to reduce an open book pelvic fracture but there is ongoing haemo-dynamic instability, what should be done?
Angiogram and embolisation, or open packing of the pelvis if already undergoing surgery
Why is a PR examination necessary for pelvic fractures?
Assess sacral nerve root function and look for presence of blood
What does the presence of blood on a PR exam indicate?
Rectal tear, meaning the injury is an ‘open fracture’ which decreases the prognosis
What type of pelvic fracture do low energy pubic rami fractures in the elderly tend to be?
Displaced lateral compression
How are low energy pelvic fractures in elderly patients treated?
Conservative management
What is the acetabulum?
The intra-articular section of the pelvis
Posterior wall fractures of the acetabulum can be associated with what injury?
Hip dislocation
What imaging techniques can be used for acetabulum fractures?
X-ray (AP and oblique) and CT
How are small, undisplayed acetabular fractures treated?
Conservatively
If an acetabular fracture is unstable or displaced in a young patient, how are they treated?
Anatomic reduction and rigid fixation to prevent post traumatic OA
If an acetabular fracture is unstable or displaced in an older patient, how are they treated?
Hip replacement
