Sacral insufficiency fracture
- Typically, patients present with groin, low back, or buttock pain.
- Patients present with either no history of trauma or a history of low impact trauma.
 Imaging Findings
 Plain film
- Most common finding is a sclerotic band or line.
- Lytic fracture line or cortical break rarely is observed.
- Sacral fractures typically are oriented vertically and located parallel to the sacroiliac joints.
- Linear fracture line with surrounding sclerosis is observed.
- Decreased signal on T1-weighted images and increased signal on T2-weighted images.
- Signal changes are seen as linear bands within the sacral ala and body and are parallel to the sacroiliac joints.
- On T2-weighted images, the fracture line may be seen if it is surrounded by adjacent marrow edema.
 Nuclear Medicine
- H or "Honda sign" which indicated horizontal involvement of the sacrum and vertical involvement of the sacral ala
- The "dot and dash" pattern is another common appearance.
Patient #1: Lower back pain. History of pelvic radiation therapy
 See Also
 External Links
- Wilfred CG. E-medicine rads article