What is the treatment for sacral insufficiency fracture?

Treatment for Sacral Insufficiency Fractures

Most sacral insufficiency fractures should be managed conservatively with early mobilization, multimodal pain management, and osteoporosis treatment, reserving sacroplasty for patients with persistent pain after 4-6 weeks of conservative therapy, and surgical fixation only for unstable or displaced fractures. 1, 2

Initial Conservative Management (First-Line Treatment)

Conservative therapy is the standard initial approach for stable, non-displaced sacral insufficiency fractures and achieves significant improvements in mobility and pain in the majority of patients. 1, 3

Core Components of Conservative Treatment:

• Early mobilization with weight-bearing as tolerated, avoiding prolonged bed rest to reduce risk of deep venous thrombosis 3, 4
• Multimodal pain management including NSAIDs, acetaminophen, and opioids if necessary for breakthrough pain 2, 3
• Physical therapy focused on gait training, balance exercises, and progressive strengthening 3
• Lumbosacral orthosis (TLSO) for stable S3 fractures to reduce pain and improve mobility, particularly in elderly patients 1

Duration and Expected Outcomes:

• Conservative therapy typically requires 4-6 weeks before determining treatment failure 5, 2
• Patients show measurable improvements in Barthel Index and Tinetti Mobility Test scores regardless of whether fractures are unilateral or bilateral 3
• Even patients with both anterior and posterior pelvic ring injuries demonstrate improvement with conservative management 3

Osteoporosis Management (Critical Component)

Addressing the underlying bone pathology is essential to prevent future fractures and optimize healing. 5, 2

• Anabolic agents (teriparatide, abaloparatide) should be initiated prior to or in conjunction with any intervention, as they improve patient outcomes 5
• Vitamin D and calcium supplementation to correct deficiencies 2
• Bisphosphonates or denosumab for long-term osteoporosis management after acute healing 2

Sacroplasty (Second-Line Treatment)

Sacroplasty should be considered for patients who fail conservative management after 4-6 weeks, those unable to tolerate immobilization, or patients with very low bone mineral density. 5, 2

Patient Selection Criteria:

• Persistent pain despite adequate conservative therapy (typically >4-6 weeks) 5, 2
• Inability to tolerate prolonged immobilization due to medical comorbidities 5
• Low bone mineral density where prolonged healing is unlikely 5
• Patients requiring earlier return to activities of daily living 4

Efficacy and Safety:

• Mean pain reduction of 5.8 points on VAS from pre-procedure to latest follow-up 4
• Provides rapid and durable pain relief with earlier recovery compared to conservative management 5, 4
• Low complication rate: cement extravasation is most common but rarely clinically significant 4
• S1 radicular pain occurs rarely, and persistent pain requiring reoperation is uncommon (12.5% in one series) 4

Technical Approaches Available:

Multiple techniques exist including short-axis, long-axis, coaxial, transiliac, interpedicular, and balloon-assisted approaches 5

Surgical Fixation (Reserved for Specific Indications)

Surgical fixation is necessary for rotationally or vertically unstable sacral fractures, or displaced fractures. 1, 2

Indications for Surgery:

• Vertically unstable sacral fractures requiring spinopelvic fixation for immediate weight-bearing 1
• Rotationally unstable fractures with significant pelvic ring disruption 1
• Displaced fractures that cannot be managed conservatively 1, 2
• Severe bilateral fractures where cement alone may not withstand shear forces at the lumbosacral junction 6

Surgical Options:

• Iliosacral screw fixation 2
• Transsacral bar or screw fixation 2
• Transiliac internal fixation 2
• Lumbopelvic fixation for complex instability 2
• CT fluoroscopy-guided transiliosacral rod placement in conjunction with sacroplasty for severe bilateral fractures 6

Critical Pitfalls to Avoid

• Do not assume bracing alone is sufficient for unstable fractures that require surgical fixation, as this leads to poor outcomes 1
• Do not fail to recognize associated pelvic ring injuries that may influence treatment decisions and stability assessment 1
• Do not dismiss vague pelvic pain in elderly patients as "arthritis" without appropriate imaging, as presentation is often insidious 7
• Do not rely solely on radiographs for diagnosis, as they miss approximately 35% of sacral fractures; proceed to CT or MRI if clinical suspicion remains high 8, 7
• Do not neglect osteoporosis treatment, as addressing the underlying bone pathology is essential for healing and preventing future fractures 5, 2

Treatment Algorithm Summary

1. Stable, non-displaced fractures: Conservative management for 4-6 weeks with mobilization, pain control, orthosis, and osteoporosis treatment 1, 2, 3
2. Persistent pain after conservative therapy: Sacroplasty with bone health optimization 5, 4
3. Unstable or displaced fractures: Surgical fixation with appropriate technique based on fracture pattern 1, 2