Pelvis Pathologies

Question 1

What are minimal displacement fractures associated with

Answer 1

major soft tissue damage - sharp edges of fractures can lacerate the soft tissue organs within

Question 2

What do impact injuries do to the bone and what can the soft tissues around it do

Answer 2

impact injuries cause the bones to move out of position but the elastic recoil of the tissues can cause the bones to return to their original position

Question 3

Why can diagnostic images be misleading and what is recommended

Answer 3

because they don’t reveal extent of injury and therefore CT is recommended to fully assess the damage

Question 4

What does ABCs stand for

Answer 4

Alignment - of bones in relation to each other
Bones - is trabeculae pattern interrupted, definitive corticol outlines?
Cartilage - joint spaces widened
soft tissue - shadowing indicating swelling?/haemorrhage from internal bleeding? (causes the peri-vesical fat pad around bladder to become displaced) = both a result of pelvic trauma/# damage

Question 5

Describe the Pelvis Ring

Answer 5

the pelvis has a main ring and 2 smaller obturator foramen

Question 6

How is the stability of the pelvis maintained

Answer 6

by the strongest ligaments in the body

Question 7

What are the name of the #s that are stable (don’t break the ring)

Answer 7

Avulsion #
Ischial/Pubic ramus #
Sacral #

Question 8

Pubic Ramus # - most common in? result of?

Answer 8

most common in elderly as a result of a fall from a standing position or involvement in motor vehicle accident

Question 9

Pubic Ramus # - symptoms? treatment? meds? recovery time?

Answer 9

experience groin & leg pain that may prevent them walking
typically heal without surgery and don’t usually cause permanent disabilities
Analgesics & non-steroidal anti-inflammatory meds used to treat symptoms
Pt encouraged to weightbear ASAP as pubic ramus has minor involvement in structural support
recovery = usually 2 months

Question 10

What are 2 additional #s that are included as a stable #? result of?

Answer 10

Duverney # - vertically in periphery, often result from a direct blow
Avulsion # AIIS - often teens (14-17), most often in kicking sports

Question 11

Sacral # - stable/unstable? most common in? result of?

Answer 11

can be stable and unstable depending on mechanism of injury
common in pelvic ring injuries (30-45%)
affects young adults = high energy trauma
affects elderly = low energy falls

Question 12

What can happen if a sacral # goes undiagnosed? What is an important factor in predicting the outcome for a patient

Answer 12

may result in neurologic compromise (25% of these types of injuries are involved with this) - the presence of a neurological deficit is the most important factor in predicting outcome

Question 13

Give 4 symptoms that are a result of a neurological deficit

Answer 13

lower extremity problems
urinary dysfunction
rectal dysfunction
sexual dysfunction

Question 14

What is the difference between a stable sacral # and an unstable sacral # and how does the treatment differ?

Answer 14

Stable # - # with no neurological deficit = non-surgery / progressive WB activities
Unstable # - # with neurological deficit = surgical intervention needed with screw/plate/fixation

Question 15

33% of pelvic #s are …

Answer 15

unstable and involve risk of haemorrhage

Question 16

What is an indication of a break in the pelvic ring?

Answer 16

widening of the symphysis pubis or SI joints

Question 17

How are #s classified?

Answer 17

by mechanism of injury as this results in different #s

Question 18

Name 3 mechanisms of injury for a pelvic #

Answer 18

lateral compression
anterior compression
vertical shear
(complex - involve a combo of forces and results in a range of associated injuries)

Question 19

What % of #s are lateral compression #s?
what could this be caused by?
results in?

Answer 19

around 60%
rollover motor vehicle accidents
causes superior and inferior ramus #s
vertical # of sacrum or sacral crush # and/or widening of SIJs

Question 20

When does a lateral compression # occur?

Answer 20

when there is a internal rotation of 1 iliac wing causing a unilateral sacral compression # whilst the same forces cause external rotation of opposite hemi-pelvis resulting in diastasis of SIJ - WIND SWEPT PELVIS

Question 21

What is the treatment for a lateral compression #?

Answer 21

simple incomplete # = non-operative and protective WB
more serious unstable # = surgical intervention, ORIF screws/plates
other surgery may be required if there is also injury to soft tissue organs of the pelvic cavity

Question 22

What occurs as a result of an anterior compression # (OPEN BOOK)?

Answer 22

complex pelvic #
anterior compression force disrupts SIJs by more than 4mm causing diastasis of symph pubis of more than 5mm (pubic rami may be #’d in vertical orientation instead) and externally rotating each hemi-pelvis

Question 23

What is the treatment for an anterior compression #?

Answer 23

If symph widening < 2.5cm = non-operable, protected WB
If symph widening > 2.5cm and SIJs affected = symphyseal plate/screws or external fixator used depending on severity of SIJ displacement
other surgery possibly required if there is injury to the soft tissue organs of the pelvic cavity

Question 24

What is a vertical shear (vertical force) # a result of? what happens to the bones?

Answer 24

often suspected following a fall where force travels upwards through the body following impact / heavy weight falling onto shoulders
bones affected either crush/compress/fold inwards following vertical influence to the pelvis

Question 25

Describe the Malgaigne # involved in a vertical shear # and how does it present

Answer 25

unstable and disrupts SIJ (considered a stabilising influence to the pelvis)
presents with shortening of the leg on the affected side

Question 26

What is a common variant to a vertical shear # and what is the result of this variant

Answer 26

common variants involve the ileum/sacral wing rather than the SIJs
results in an unstable lateral fragment which contains the acetabulum

Question 27

What is a further common association with a vertical shear #?

Answer 27

diastase of the symph pubis

Question 28

What is a vertical shear #associated with? how is this rectified?

Answer 28

the highest risk of hypovolemic shock (decrease in volume of blood in body due to blood loss) - 63%
surgical intervention to rectify bony injury, involves stabilisation with plate/screws needed

Question 29

What additional type of # is associated with anterior compression #s and vertical shear #s?

Answer 29

acetabular #s