Sacral insufficiency fractures are an often under diagnosed condition in the elderly population, typically presenting with severe low back pain resulting in immobility. The diagnosis can be complicated by the fact that radiographic assessment of the sacrum is difficult and lower spine (lumbar) imaging is frequently not specifically targeted at the sacrum. Sacral vertebroplasty, a procedural extension of percutaneous vertebroplasty, involves the injection of bone cement into the sacrum with the aim of alleviating pain and facilitating more rapid mobilization than conservative therapy alone allows.
Physicians can treat sacral insufficiency fractures with either long-axis or short-axis approaches. Both techniques are effective depending on the patient’s specific issues and can have good outcomes1, although the short-axis approach requires physicians to make two trocar insertions while the long-axis approach may only require one.
"Due to variation in patient anatomy and fracture location, I select either the long-axis or short-axis approach for safer and more effective PMMA distribution," says Jeffrey W. Miller, MD, Director of Neuroendovascular Surgery at Bronson Methodist Hospital and clinical faculty at Western Michigan University School of Medicine. "Our recent cadaveric trial confirmed safety of both approaches and support this position with no PMMA extravasation."
The procedure is traditionally done under CT scans or fluoroscopy. Many physicians find that CT is superior for visualization, but physicians often can’t see the surgical site while injecting the cement in real time. However, there is technology available for advanced visualization throughout navigation and cement injection.
"At Bronson, we utilize biplane fluoroscopic equipment with Dyna CT capability," says Dr. Miller. "Prior to the sacral vertebroplasty, a 3D reconstruction of the sacrum and fracture are obtained on the operative table. This allows us to select the safest approach for cement delivery. The biplane unit allows optimal fluoroscopic observation of cement delivery. Finally, a post procedure Dyna CT is performed to confirm the desired fracture treatment."
The Dyna CT is more efficient than traditional visualization because physicians don’t need to move patients and switch visualization equipment. The procedure time is decreased and patients aren’t moved as much during the procedure.
When physicians are able to visualize the patient’s anatomy, they’re more likely to achieve the best possible outcome. Typically, complications occur when physicians can’t see the surgical site very well, says Dr. Miller. A few of the most common historical complications of sacroplasty include:
Extravasation of cement into either the sacroiliac joint or sacral neural foramina
• Disruption of the sacrum from needle placement
• Infection
• Pulmonary embolism
• Bleeding
Cement extravasations are the most common historical complication for sacroplasty 2,3 but physicians can use high viscosity cement to reduce the risk. There is a more predictable delivery with high viscosity cement, leading to fewer issues. In June, Stryker’s VertaPlex HV®, a high viscosity bone cement, became the first PMMA to receive 510(k) clearance for the fixation of pathological fractures of the sacral vertebral body or ala using sacral vertebroplasty or sacroplasty.
"The main problem with sacral vertebroplasty/sacroplasty is the bone of the sacrum is more porous than the bone of the vertebral bodies, and you’re injecting cement into that bone during surgery," says Dr. Miller. "There is a chance that injected cement will travel to the nerve foramina on one side or the sacroiliac joint on the other. However the thicker cement is less likely to travel outside of the surgical site."
Physicians will choose to perform sacroplasty or sacral vertebroplasty based on their training and the patient’s specific anatomy.
"I have already witnessed dramatic patient improvement in my own practice by incorporating sacral vertebroplasty and sacroplasty as part of my intraoperative protocol." says Dr. Miller.
This article is sponsored by Stryker.