About Sacral Insufficiency Fractures (SIF)
Sacral insufficiency fractures (SIF) are a commonly misdiagnosed painful condition in patients with osteoporosis.
The sacrum is a triangular shaped bone that connects the spine to the pelvis. This lowermost component of the spine is prone to age related bone loss similar to the vertebrae of the spine. When weakened the bone may fracture with minimal or no trauma and result in severe pain and loss of mobility. Osteoporosis affects over 700000 people per year. Statistically, 50% of women and 25% of men will experience an osteoporotic compression fracture in their lifetime.
Facts about sacral insufficiency fractures
- Most patients have delay in the diagnosis of sacral fracture as the symptoms can be more vague than compression fractures that occur in the spine
- Patients with history of lumbar fusion surgery, total hip replacement and prior vertebral compression fracture as well as patients with history or cancer and pelvic radiation are at higher risk for sacral fracture
- Conservative management of SIF’s including bed rest and analgesics alone are commonly unsuccessful resulting in chronic pain and reduced mobility.
Symptoms of sacral insufficiency fracture
- Generalized pain in the “sit” bones or tail bone
- Low back or sacral pain with radiation of pain to the hip, groin or legs
- Pain with movement such as transitioning from lying to sitting or sitting to standing
Imaging exams for detecting sacral insufficiency fractures
- MRI and bone scan are highly sensitive for SIF
- CT scan is able to detect fractures with displacement or visible fracture lines
- Radiographs are not useful for the detection of SIF
Treatments for sacral insufficiency fractures
Minimally invasive therapies:
- Sacral augmentation: The fractured osteoporotic bone is injected with a medical cement through a small needle access. This procedure is performed on one or both sides of the sacrum. A cavity may be created within the bone to aid in safe cement injection. If a cavity for cement is created it is termed lumbosacral kyphoplasty. The procedure is performed with the patient lying on their stomach either in a CT scanner or under live X-Ray. The procedure is performed at a hospital on an outpatient basis. Most procedures will be performed under anesthesia. Most patients have a rapid reduction in their pain following the procedure. Further pain relief comes with subsequent healing, physical therapy and resumption of activity.
- Sacral stabilization: Displaced SIF’s are more severe. The pain and disability of displaced sacral fractures may not resolve with sacral augmentation alone. Percutaneous augmented orthopedic screw fixation is a highly specialized minimally invasive procedure performed by RIA physicians to unite the displaced fracture with surgical screws in addition to medical cement.
All patients with osteoporotic fractures benefit from medical therapy.
Your provider will typically discuss initiation of these agents in follow up after sacral augmentation.
- Anabolic agents: These medications are taken for 1-2 years and result in an increase in bone density.
- Bisphosphonates: These medications may be taken orally or injected and prevent resorption of existing bone.