Learning objectives
(1) To provide a brief overview ofpelvic and sacral bony anatomy.
(2) To review imaging findings of sacral and pelvic insufficiency fractures (ISF) and aassociated complications.
(3) Review potential pitfalls in imaging interpretation to prevent unnecessary work-up oradverse patient outcomes.
(4) Review cases to reinforce teaching points.
Background
The incidence of sacral and pelvic ISFs is increasing due to rapidly aging populations.
ISFs area significant cause of functional disability in the elderly [1].
They are a result of normal stresses on abnormal bone which are largely a result of osteoporosis.
Patientsmay present with chronic lower back,
pelvic or groin pain with (usually minor) or without trauma [2,3].
Other risk factors include prior radiotherapy to the pelvis (e.g.
for sacral chordomas or cervical cancer),
prolonged corticosteroidtherapy,chronicmedical conditions such as rheumatoid arthritis and renal failure,...
Imaging findings OR Procedure Details
OSSEOUS ANATOMY
The sacropelvic structural stability is conferred bythe sacrum and bilateral innominate bones,
andligaments thatcollectivelyform the pelvic ring's osteo-ligamentous complex [7].
The sacrum is a triangular bone in the lower part of the vertebral column.
It articulates with the last lumbar vertebra (typically L5) and coccyx,
at its base and apex,
respectively.
Laterally,
it articulates with the iliac bones on either side,
forming the sacroiliac joints.
Dorsally,
there are the sacral foramina,
where the anterior and posterior divisions of the sacral nerves exit,
and...
Conclusion
In this pictorial,
we reviewed the anatomy and pathological features of pelvic and sacral insufficiency fractures,
including important diagnostic imaging characteristicsas well asinjuries that are related to these fractures.
Lastly,
we highlighted several imaging pearls and potentialpitfalls and used few case illustrations to reinforce these teaching points.
As osteoporosis,
and consequently ISFs,
become increasingly importantin terms of social and economic significance in aging populations,it isequallty important for clinicians and radiologists to not only consider ISFs in their diagnosis,
in patients with lower back,
gluteal or...
References
(1) Taillandier J,
Langue F,
Alemanni M,
Taillandier-Heriche E.
Mortality and functional outcomes of pelvic insufficiency fractures in older patients.
Joint Bone Spine 2003; 70:287–289.
(2) Kiuru MJ,
Pihlajamaki HK,
Ahovuo JA.
Fatigue stress injuries of the pelvic bones and proximal femur: evaluation with MR imaging.
European Radiology 2003; 13:605-611.
(3)Schindler,
OS.
Sacral insufficiency fractures.
Journal of Orthopaedic Surgery 2007;15(3):339-46.
(4)Cabarrus MC,
Ambekar A,
LuY,
Link TM.
MRI and CT of Insufficiency Fractures of the pelvis and the proximal femur.American Journal of Roentgenology 2008; 191:995–1001....