Neurovascular
Procedure Guide
Symptomatic, stable sacral insufficiency or pathologic fractures.
There are multiple models for categorizing sacral fractures though they reflect morphology and mechanism of trauma rather than being as helpful for management, e.g., Young-Burgess (trauma mechanism), Denis (zones 1-3), and Bakker
Unstable sacral fracture, i.e., displaced H-shaped fractures and those associated with both dorsal and ventral pelvic fractures
Septicemia / Active sacral osteomyelitis
Allergy to bone cement or opacification agents
INR >1.3, Plts <70K, or other uncorrected coagulopathy
Generally safe and very effective. Systematic review and meta-analysis of 861 patients showed clinical success in 95.7% with 0.3% major complications and significant decrease in pain scores from 8.32 to 3.55 within 1-2 days and down to 0.92 at 12 months
Main alternative is conservative management but often not effective or requires prolonged bedrest. This would be most appropriate for chronic sacral insufficiency fractures and those associated with mild to no pain.
Surgical fixation often is not offered because the patients tend to be older with many comorbidities.
Labs: PT/INR, CBC, and CMP
CT to assess fracture pattern / MR to characterize soft tissue and acuity
Prophylactic antibiotics: 1g Ancef
Sacroplasty can be performed with fluoroscopic or CT guidance. Fluoroscopy is often better for the longitudinal approach which can be faster. CT allows for better targeting of a specific fracture or lesion particularly if combining with RFA. The steps below are for fluoroscopic guidance.
Images are taken for Medtronic and Stryker sponsored lectures on sacroplasty by Drs. Labib Haddad, Therea Pazionis, and Anthony Brown
Longitudinal approach
Obtain true AP using the L5-S1 disk space and spinous processes.
Contralateral oblique (often 20-30*) to line up SI joint.
Draw line (in mind or on patient) along SI joint and sacral neuroforamen. The lines should make a skinny V-shape. Entry to the sacrum should be near the point of the V. Some will choose a skin entry site even lower to get more cement lower within the sacrum but this may not matter since most of the work is being done at S1 and S2.
Anesthetize the skin and use lidocaine needle or spinal needle to plan trajectory, first in the contralateral oblique down to the bone and then true lateral lining up the iliac wings. Ideal cannula end point is the middle of an X-shape made in the S1 vertebral body. Often the iliac wings lie in this region on lateral projection. Adjust spinal needle to target this point.
Replace spinal needle with introducer cannula and check trajectory in oblique and lateral.
Advance in slow increments checking oblique and lateral views. It is better to edge close to the SI joint than neuroforamen.
Once in position, remove the stylet and begin injecting cement in lateral view until cement starts to emerge.
Switch to oblique or AP view for monitoring cement distribution. It should flower out in trabecular bone and may travel beyond the anterior cortex of S1 in lateral view since the sacral ala extends further anterior. It may also track medially or laterally in linear configuration along fracture lines. You can pause on that side and fill the other, allowing the cement to harden before injecting more. Cement in the SI joint is not ideal but likely inconsequential. Terminate the procedure if cement tracks in linear configuration superomedially as this is likely in a neuroforamen mimicking a pseudo-epidurogram. Often volume ranges from 4-20 mL but some report routine giving 30-40 mL.
Axial Approach
Obtain true AP using the L5-S1 disk space and spinous processes.
Plan skin entry site slightly superomedial to S1 pedicle
Contralateral oblique (often 20-30*) to line up SI joint.
Anesthetize the skin and use lidocaine needle or spinal needle to plan trajectory, first in the contralateral oblique down to the bone and then true lateral lining up the iliac wings. Trajectory should course lateral into the sacral ala targeting the middle of an X-shape made in the S1 vertebral body on lateral view.
Replace spinal needle with introducer cannula and check trajectory in oblique and lateral.
Advance in slow increments checking oblique and lateral views. Once in position, remove the stylet and begin injecting cement in lateral view until cement starts to emerge.
Switch to oblique or AP view for monitoring cement distribution. See above re normal distribution.
This can be repeated at other levels such as S2.
Only reported complication is cement extravasation which is rare and often clinically insignificant. In the meta-analysis mentioned above, only 5 patients had clinically significant extravasation causing radicular pain, 2 resolved with anti-inflammatory medication and 3 required surgical decompression.
Other theoretical complications include bleeding, infection, and allergic reaction
Observe. Some tenderness and bruising are common.
Consider PT/OT referral to help patients regain strength and address potential habits putting them at risk for additional fractures.
Follow up 1-day, 1-week, 1-month, and 6-months post-op.